From: Junio C Hamano <gitster@pobox.com>
Date: Tue, 24 Apr 2018 02:24:22 +0000 (+0900)
Subject: Merge branch 'bw/protocol-v2' into HEAD
X-Git-Tag: v2.18.0-rc0~60^2~3
X-Git-Url: https://git.lorimer.id.au/gitweb.git/diff_plain/bbc39d4020372a0bf8aa399c7550ba58312adfa1?ds=inline;hp=-c

Merge branch 'bw/protocol-v2' into HEAD

* bw/protocol-v2: (35 commits)
remote-curl: don't request v2 when pushing
remote-curl: implement stateless-connect command
http: eliminate "# service" line when using protocol v2
http: don't always add Git-Protocol header
http: allow providing extra headers for http requests
remote-curl: store the protocol version the server responded with
remote-curl: create copy of the service name
pkt-line: add packet_buf_write_len function
transport-helper: introduce stateless-connect
transport-helper: refactor process_connect_service
transport-helper: remove name parameter
connect: don't request v2 when pushing
connect: refactor git_connect to only get the protocol version once
fetch-pack: support shallow requests
fetch-pack: perform a fetch using v2
upload-pack: introduce fetch server command
push: pass ref prefixes when pushing
fetch: pass ref prefixes when fetching
ls-remote: pass ref prefixes when requesting a remote's refs
transport: convert transport_get_remote_refs to take a list of ref prefixes
...
---

bbc39d4020372a0bf8aa399c7550ba58312adfa1
diff --combined Documentation/Makefile
index 6232143cb9,b105775acd..fa9e5c0acd
--- a/Documentation/Makefile
+++ b/Documentation/Makefile
@@@ -72,12 -72,12 +72,13 @@@ TECH_DOCS += SubmittingPatche
  TECH_DOCS += technical/hash-function-transition
  TECH_DOCS += technical/http-protocol
  TECH_DOCS += technical/index-format
 +TECH_DOCS += technical/long-running-process-protocol
  TECH_DOCS += technical/pack-format
  TECH_DOCS += technical/pack-heuristics
  TECH_DOCS += technical/pack-protocol
  TECH_DOCS += technical/protocol-capabilities
  TECH_DOCS += technical/protocol-common
+ TECH_DOCS += technical/protocol-v2
  TECH_DOCS += technical/racy-git
  TECH_DOCS += technical/send-pack-pipeline
  TECH_DOCS += technical/shallow
diff --combined Documentation/gitremote-helpers.txt
index 4b8c93ec59,cd9b34d230..9d1459aac6
--- a/Documentation/gitremote-helpers.txt
+++ b/Documentation/gitremote-helpers.txt
@@@ -102,6 -102,14 +102,14 @@@ Capabilities for Pushin
  +
  Supported commands: 'connect'.
  
+ 'stateless-connect'::
+ 	Experimental; for internal use only.
+ 	Can attempt to connect to a remote server for communication
+ 	using git's wire-protocol version 2.  See the documentation
+ 	for the stateless-connect command for more information.
+ +
+ Supported commands: 'stateless-connect'.
+ 
  'push'::
  	Can discover remote refs and push local commits and the
  	history leading up to them to new or existing remote refs.
@@@ -136,6 -144,14 +144,14 @@@ Capabilities for Fetchin
  +
  Supported commands: 'connect'.
  
+ 'stateless-connect'::
+ 	Experimental; for internal use only.
+ 	Can attempt to connect to a remote server for communication
+ 	using git's wire-protocol version 2.  See the documentation
+ 	for the stateless-connect command for more information.
+ +
+ Supported commands: 'stateless-connect'.
+ 
  'fetch'::
  	Can discover remote refs and transfer objects reachable from
  	them to the local object store.
@@@ -375,6 -391,22 +391,22 @@@ Supported if the helper has the "export
  +
  Supported if the helper has the "connect" capability.
  
+ 'stateless-connect' <service>::
+ 	Experimental; for internal use only.
+ 	Connects to the given remote service for communication using
+ 	git's wire-protocol version 2.  Valid replies to this command
+ 	are empty line (connection established), 'fallback' (no smart
+ 	transport support, fall back to dumb transports) and just
+ 	exiting with error message printed (can't connect, don't bother
+ 	trying to fall back).  After line feed terminating the positive
+ 	(empty) response, the output of the service starts.  Messages
+ 	(both request and response) must consist of zero or more
+ 	PKT-LINEs, terminating in a flush packet. The client must not
+ 	expect the server to store any state in between request-response
+ 	pairs.  After the connection ends, the remote helper exits.
+ +
+ Supported if the helper has the "stateless-connect" capability.
+ 
  If a fatal error occurs, the program writes the error message to
  stderr and exits. The caller should expect that a suitable error
  message has been printed if the child closes the connection without
@@@ -466,13 -498,6 +498,13 @@@ set by Git if the remote helper has th
  	Transmit <string> as a push option. As the push option
  	must not contain LF or NUL characters, the string is not encoded.
  
 +'option from-promisor' {'true'|'false'}::
 +	Indicate that these objects are being fetched from a promisor.
 +
 +'option no-dependents' {'true'|'false'}::
 +	Indicate that only the objects wanted need to be fetched, not
 +	their dependents.
 +
  SEE ALSO
  --------
  linkgit:git-remote[1]
diff --combined Makefile
index f181687250,fb2175bcf1..c29c1323c1
--- a/Makefile
+++ b/Makefile
@@@ -23,16 -23,17 +23,16 @@@ all:
  # it at all).
  #
  # Define NO_OPENSSL environment variable if you do not have OpenSSL.
 -# This also implies BLK_SHA1.
  #
  # Define USE_LIBPCRE if you have and want to use libpcre. Various
  # commands such as log and grep offer runtime options to use
  # Perl-compatible regular expressions instead of standard or extended
  # POSIX regular expressions.
  #
 -# Currently USE_LIBPCRE is a synonym for USE_LIBPCRE1, define
 -# USE_LIBPCRE2 instead if you'd like to use version 2 of the PCRE
 -# library. The USE_LIBPCRE flag will likely be changed to mean v2 by
 -# default in future releases.
 +# USE_LIBPCRE is a synonym for USE_LIBPCRE2, define USE_LIBPCRE1
 +# instead if you'd like to use the legacy version 1 of the PCRE
 +# library. Support for version 1 will likely be removed in some future
 +# release of Git, as upstream has all but abandoned it.
  #
  # When using USE_LIBPCRE1, define NO_LIBPCRE1_JIT if the PCRE v1
  # library is compiled without --enable-jit. We will auto-detect
@@@ -294,14 -295,11 +294,14 @@@
  #
  # Define PERL_PATH to the path of your Perl binary (usually /usr/bin/perl).
  #
 -# Define NO_PERL_MAKEMAKER if you cannot use Makefiles generated by perl's
 -# MakeMaker (e.g. using ActiveState under Cygwin).
 -#
  # Define NO_PERL if you do not want Perl scripts or libraries at all.
  #
 +# Define NO_PERL_CPAN_FALLBACKS if you do not want to install bundled
 +# copies of CPAN modules that serve as a fallback in case the modules
 +# are not available on the system. This option is intended for
 +# distributions that want to use their packaged versions of Perl
 +# modules, instead of the fallbacks shipped with Git.
 +#
  # Define PYTHON_PATH to the path of your Python binary (often /usr/bin/python
  # but /usr/bin/python2.7 on some platforms).
  #
@@@ -335,13 -333,6 +335,13 @@@
  # when hardlinking a file to another name and unlinking the original file right
  # away (some NTFS drivers seem to zero the contents in that scenario).
  #
 +# Define INSTALL_SYMLINKS if you prefer to have everything that can be
 +# symlinked between bin/ and libexec/ to use relative symlinks between
 +# the two. This option overrides NO_CROSS_DIRECTORY_HARDLINKS and
 +# NO_INSTALL_HARDLINKS which will also use symlinking by indirection
 +# within the same directory in some cases, INSTALL_SYMLINKS will
 +# always symlink to the final target directly.
 +#
  # Define NO_CROSS_DIRECTORY_HARDLINKS if you plan to distribute the installed
  # programs as a tar, where bin/ and libexec/ might be on different file systems.
  #
@@@ -435,10 -426,6 +435,10 @@@
  # to say "export LESS=FRX (and LV=-c) if the environment variable
  # LESS (and LV) is not set, respectively".
  #
 +# Define TEST_SHELL_PATH if you want to use a shell besides SHELL_PATH for
 +# running the test scripts (e.g., bash has better support for "set -x"
 +# tracing).
 +#
  # When cross-compiling, define HOST_CPU as the canonical name of the CPU on
  # which the built Git will run (for instance "x86_64").
  
@@@ -481,14 -468,14 +481,14 @@@ ARFLAGS = rc
  # This can help installing the suite in a relocatable way.
  
  prefix = $(HOME)
 -bindir_relative = bin
 -bindir = $(prefix)/$(bindir_relative)
 +bindir = $(prefix)/bin
  mandir = $(prefix)/share/man
  infodir = $(prefix)/share/info
  gitexecdir = libexec/git-core
  mergetoolsdir = $(gitexecdir)/mergetools
  sharedir = $(prefix)/share
  gitwebdir = $(sharedir)/gitweb
 +perllibdir = $(sharedir)/perl5
  localedir = $(sharedir)/locale
  template_dir = share/git-core/templates
  htmldir = $(prefix)/share/doc/git-doc
@@@ -498,13 -485,11 +498,13 @@@ lib = li
  # DESTDIR =
  pathsep = :
  
 +bindir_relative = $(patsubst $(prefix)/%,%,$(bindir))
  mandir_relative = $(patsubst $(prefix)/%,%,$(mandir))
  infodir_relative = $(patsubst $(prefix)/%,%,$(infodir))
 +gitexecdir_relative = $(patsubst $(prefix)/%,%,$(gitexecdir))
  htmldir_relative = $(patsubst $(prefix)/%,%,$(htmldir))
  
 -export prefix bindir sharedir sysconfdir gitwebdir localedir
 +export prefix bindir sharedir sysconfdir gitwebdir perllibdir localedir
  
  CC = cc
  AR = ar
@@@ -554,7 -539,6 +554,7 @@@ SCRIPT_PERL 
  SCRIPT_PYTHON =
  SCRIPT_SH =
  SCRIPT_LIB =
 +TEST_BUILTINS_OBJS =
  TEST_PROGRAMS_NEED_X =
  
  # Having this variable in your environment would break pipelines because
@@@ -652,7 -636,6 +652,6 @@@ PROGRAM_OBJS += imap-send.
  PROGRAM_OBJS += sh-i18n--envsubst.o
  PROGRAM_OBJS += shell.o
  PROGRAM_OBJS += show-index.o
- PROGRAM_OBJS += upload-pack.o
  PROGRAM_OBJS += remote-testsvn.o
  
  # Binary suffix, set to .exe for Windows builds
@@@ -660,49 -643,48 +659,50 @@@ X 
  
  PROGRAMS += $(patsubst %.o,git-%$X,$(PROGRAM_OBJS))
  
 -TEST_PROGRAMS_NEED_X += test-chmtime
 -TEST_PROGRAMS_NEED_X += test-ctype
 -TEST_PROGRAMS_NEED_X += test-config
 -TEST_PROGRAMS_NEED_X += test-date
 -TEST_PROGRAMS_NEED_X += test-delta
 -TEST_PROGRAMS_NEED_X += test-drop-caches
 -TEST_PROGRAMS_NEED_X += test-dump-cache-tree
 +TEST_BUILTINS_OBJS += test-chmtime.o
 +TEST_BUILTINS_OBJS += test-config.o
 +TEST_BUILTINS_OBJS += test-ctype.o
 +TEST_BUILTINS_OBJS += test-date.o
 +TEST_BUILTINS_OBJS += test-delta.o
 +TEST_BUILTINS_OBJS += test-drop-caches.o
 +TEST_BUILTINS_OBJS += test-dump-cache-tree.o
 +TEST_BUILTINS_OBJS += test-dump-split-index.o
 +TEST_BUILTINS_OBJS += test-example-decorate.o
 +TEST_BUILTINS_OBJS += test-genrandom.o
 +TEST_BUILTINS_OBJS += test-hashmap.o
 +TEST_BUILTINS_OBJS += test-index-version.o
 +TEST_BUILTINS_OBJS += test-lazy-init-name-hash.o
 +TEST_BUILTINS_OBJS += test-match-trees.o
 +TEST_BUILTINS_OBJS += test-mergesort.o
 +TEST_BUILTINS_OBJS += test-mktemp.o
 +TEST_BUILTINS_OBJS += test-online-cpus.o
 +TEST_BUILTINS_OBJS += test-path-utils.o
 +TEST_BUILTINS_OBJS += test-prio-queue.o
 +TEST_BUILTINS_OBJS += test-read-cache.o
 +TEST_BUILTINS_OBJS += test-ref-store.o
 +TEST_BUILTINS_OBJS += test-regex.o
 +TEST_BUILTINS_OBJS += test-revision-walking.o
 +TEST_BUILTINS_OBJS += test-run-command.o
 +TEST_BUILTINS_OBJS += test-scrap-cache-tree.o
 +TEST_BUILTINS_OBJS += test-sha1-array.o
 +TEST_BUILTINS_OBJS += test-sha1.o
 +TEST_BUILTINS_OBJS += test-sigchain.o
 +TEST_BUILTINS_OBJS += test-strcmp-offset.o
 +TEST_BUILTINS_OBJS += test-string-list.o
 +TEST_BUILTINS_OBJS += test-submodule-config.o
 +TEST_BUILTINS_OBJS += test-subprocess.o
 +TEST_BUILTINS_OBJS += test-urlmatch-normalization.o
 +TEST_BUILTINS_OBJS += test-wildmatch.o
 +TEST_BUILTINS_OBJS += test-write-cache.o
 +
  TEST_PROGRAMS_NEED_X += test-dump-fsmonitor
 -TEST_PROGRAMS_NEED_X += test-dump-split-index
  TEST_PROGRAMS_NEED_X += test-dump-untracked-cache
 -TEST_PROGRAMS_NEED_X += test-example-decorate
  TEST_PROGRAMS_NEED_X += test-fake-ssh
 -TEST_PROGRAMS_NEED_X += test-genrandom
 -TEST_PROGRAMS_NEED_X += test-hashmap
 -TEST_PROGRAMS_NEED_X += test-index-version
 -TEST_PROGRAMS_NEED_X += test-lazy-init-name-hash
  TEST_PROGRAMS_NEED_X += test-line-buffer
 -TEST_PROGRAMS_NEED_X += test-match-trees
 -TEST_PROGRAMS_NEED_X += test-mergesort
 -TEST_PROGRAMS_NEED_X += test-mktemp
 -TEST_PROGRAMS_NEED_X += test-online-cpus
  TEST_PROGRAMS_NEED_X += test-parse-options
 -TEST_PROGRAMS_NEED_X += test-path-utils
+ TEST_PROGRAMS_NEED_X += test-pkt-line
 -TEST_PROGRAMS_NEED_X += test-prio-queue
 -TEST_PROGRAMS_NEED_X += test-read-cache
 -TEST_PROGRAMS_NEED_X += test-write-cache
 -TEST_PROGRAMS_NEED_X += test-ref-store
 -TEST_PROGRAMS_NEED_X += test-regex
 -TEST_PROGRAMS_NEED_X += test-revision-walking
 -TEST_PROGRAMS_NEED_X += test-run-command
 -TEST_PROGRAMS_NEED_X += test-scrap-cache-tree
 -TEST_PROGRAMS_NEED_X += test-sha1
 -TEST_PROGRAMS_NEED_X += test-sha1-array
 -TEST_PROGRAMS_NEED_X += test-sigchain
 -TEST_PROGRAMS_NEED_X += test-strcmp-offset
 -TEST_PROGRAMS_NEED_X += test-string-list
 -TEST_PROGRAMS_NEED_X += test-submodule-config
 -TEST_PROGRAMS_NEED_X += test-subprocess
  TEST_PROGRAMS_NEED_X += test-svn-fe
 -TEST_PROGRAMS_NEED_X += test-urlmatch-normalization
 -TEST_PROGRAMS_NEED_X += test-wildmatch
 +TEST_PROGRAMS_NEED_X += test-tool
  
  TEST_PROGRAMS = $(patsubst %,t/helper/%$X,$(TEST_PROGRAMS_NEED_X))
  
@@@ -751,8 -733,6 +751,8 @@@ endi
  export PERL_PATH
  export PYTHON_PATH
  
 +TEST_SHELL_PATH = $(SHELL_PATH)
 +
  LIB_FILE = libgit.a
  XDIFF_LIB = xdiff/lib.a
  VCSSVN_LIB = vcs-svn/lib.a
@@@ -819,7 -799,6 +819,7 @@@ LIB_OBJS += ewah/ewah_bitmap.
  LIB_OBJS += ewah/ewah_io.o
  LIB_OBJS += ewah/ewah_rlw.o
  LIB_OBJS += exec_cmd.o
 +LIB_OBJS += fetch-object.o
  LIB_OBJS += fetch-pack.o
  LIB_OBJS += fsck.o
  LIB_OBJS += fsmonitor.o
@@@ -841,6 -820,7 +841,7 @@@ LIB_OBJS += list-objects-filter-options
  LIB_OBJS += ll-merge.o
  LIB_OBJS += lockfile.o
  LIB_OBJS += log-tree.o
+ LIB_OBJS += ls-refs.o
  LIB_OBJS += mailinfo.o
  LIB_OBJS += mailmap.o
  LIB_OBJS += match-trees.o
@@@ -848,6 -828,7 +849,6 @@@ LIB_OBJS += merge.
  LIB_OBJS += merge-blobs.o
  LIB_OBJS += merge-recursive.o
  LIB_OBJS += mergesort.o
 -LIB_OBJS += mru.o
  LIB_OBJS += name-hash.o
  LIB_OBJS += notes.o
  LIB_OBJS += notes-cache.o
@@@ -896,6 -877,7 +897,7 @@@ LIB_OBJS += revision.
  LIB_OBJS += run-command.o
  LIB_OBJS += send-pack.o
  LIB_OBJS += sequencer.o
+ LIB_OBJS += serve.o
  LIB_OBJS += server-info.o
  LIB_OBJS += setup.o
  LIB_OBJS += sha1-array.o
@@@ -924,6 -906,7 +926,7 @@@ LIB_OBJS += tree-diff.
  LIB_OBJS += tree.o
  LIB_OBJS += tree-walk.o
  LIB_OBJS += unpack-trees.o
+ LIB_OBJS += upload-pack.o
  LIB_OBJS += url.o
  LIB_OBJS += urlmatch.o
  LIB_OBJS += usage.o
@@@ -1028,6 -1011,7 +1031,7 @@@ BUILTIN_OBJS += builtin/rev-parse.
  BUILTIN_OBJS += builtin/revert.o
  BUILTIN_OBJS += builtin/rm.o
  BUILTIN_OBJS += builtin/send-pack.o
+ BUILTIN_OBJS += builtin/serve.o
  BUILTIN_OBJS += builtin/shortlog.o
  BUILTIN_OBJS += builtin/show-branch.o
  BUILTIN_OBJS += builtin/show-ref.o
@@@ -1041,6 -1025,7 +1045,7 @@@ BUILTIN_OBJS += builtin/update-index.
  BUILTIN_OBJS += builtin/update-ref.o
  BUILTIN_OBJS += builtin/update-server-info.o
  BUILTIN_OBJS += builtin/upload-archive.o
+ BUILTIN_OBJS += builtin/upload-pack.o
  BUILTIN_OBJS += builtin/var.o
  BUILTIN_OBJS += builtin/verify-commit.o
  BUILTIN_OBJS += builtin/verify-pack.o
@@@ -1181,18 -1166,13 +1186,18 @@@ ifdef NO_LIBGEN_
  	COMPAT_OBJS += compat/basename.o
  endif
  
 -USE_LIBPCRE1 ?= $(USE_LIBPCRE)
 +USE_LIBPCRE2 ?= $(USE_LIBPCRE)
  
 -ifneq (,$(USE_LIBPCRE1))
 -	ifdef USE_LIBPCRE2
 -$(error Only set USE_LIBPCRE1 (or its alias USE_LIBPCRE) or USE_LIBPCRE2, not both!)
 +ifneq (,$(USE_LIBPCRE2))
 +	ifdef USE_LIBPCRE1
 +$(error Only set USE_LIBPCRE2 (or its alias USE_LIBPCRE) or USE_LIBPCRE1, not both!)
  	endif
  
 +	BASIC_CFLAGS += -DUSE_LIBPCRE2
 +	EXTLIBS += -lpcre2-8
 +endif
 +
 +ifdef USE_LIBPCRE1
  	BASIC_CFLAGS += -DUSE_LIBPCRE1
  	EXTLIBS += -lpcre
  
@@@ -1201,6 -1181,11 +1206,6 @@@ ifdef NO_LIBPCRE1_JI
  endif
  endif
  
 -ifdef USE_LIBPCRE2
 -	BASIC_CFLAGS += -DUSE_LIBPCRE2
 -	EXTLIBS += -lpcre2-8
 -endif
 -
  ifdef LIBPCREDIR
  	BASIC_CFLAGS += -I$(LIBPCREDIR)/include
  	EXTLIBS += -L$(LIBPCREDIR)/$(lib) $(CC_LD_DYNPATH)$(LIBPCREDIR)/$(lib)
@@@ -1289,6 -1274,7 +1294,6 @@@ ifndef NO_OPENSS
  	endif
  else
  	BASIC_CFLAGS += -DNO_OPENSSL
 -	BLK_SHA1 = 1
  	OPENSSL_LIBSSL =
  endif
  ifdef NO_OPENSSL
@@@ -1530,9 -1516,7 +1535,9 @@@ els
  	LIB_OBJS += sha1dc_git.o
  ifdef DC_SHA1_EXTERNAL
  	ifdef DC_SHA1_SUBMODULE
 +		ifneq ($(DC_SHA1_SUBMODULE),auto)
  $(error Only set DC_SHA1_EXTERNAL or DC_SHA1_SUBMODULE, not both)
 +		endif
  	endif
  	BASIC_CFLAGS += -DDC_SHA1_EXTERNAL
  	EXTLIBS += -lsha1detectcoll
@@@ -1560,6 -1544,9 +1565,6 @@@ ifdef SHA1_MAX_BLOCK_SIZ
  	LIB_OBJS += compat/sha1-chunked.o
  	BASIC_CFLAGS += -DSHA1_MAX_BLOCK_SIZE="$(SHA1_MAX_BLOCK_SIZE)"
  endif
 -ifdef NO_PERL_MAKEMAKER
 -	export NO_PERL_MAKEMAKER
 -endif
  ifdef NO_HSTRERROR
  	COMPAT_CFLAGS += -DNO_HSTRERROR
  	COMPAT_OBJS += compat/hstrerror.o
@@@ -1746,20 -1733,16 +1751,20 @@@ ETC_GITATTRIBUTES_SQ = $(subst ','\'',$
  DESTDIR_SQ = $(subst ','\'',$(DESTDIR))
  bindir_SQ = $(subst ','\'',$(bindir))
  bindir_relative_SQ = $(subst ','\'',$(bindir_relative))
 +mandir_SQ = $(subst ','\'',$(mandir))
  mandir_relative_SQ = $(subst ','\'',$(mandir_relative))
  infodir_relative_SQ = $(subst ','\'',$(infodir_relative))
 +perllibdir_SQ = $(subst ','\'',$(perllibdir))
  localedir_SQ = $(subst ','\'',$(localedir))
  gitexecdir_SQ = $(subst ','\'',$(gitexecdir))
 +gitexecdir_relative_SQ = $(subst ','\'',$(gitexecdir_relative))
  template_dir_SQ = $(subst ','\'',$(template_dir))
  htmldir_relative_SQ = $(subst ','\'',$(htmldir_relative))
  prefix_SQ = $(subst ','\'',$(prefix))
  gitwebdir_SQ = $(subst ','\'',$(gitwebdir))
  
  SHELL_PATH_SQ = $(subst ','\'',$(SHELL_PATH))
 +TEST_SHELL_PATH_SQ = $(subst ','\'',$(TEST_SHELL_PATH))
  PERL_PATH_SQ = $(subst ','\'',$(PERL_PATH))
  PYTHON_PATH_SQ = $(subst ','\'',$(PYTHON_PATH))
  TCLTK_PATH_SQ = $(subst ','\'',$(TCLTK_PATH))
@@@ -1860,6 -1843,9 +1865,6 @@@ all:
  ifndef NO_TCLTK
  	$(QUIET_SUBDIR0)git-gui $(QUIET_SUBDIR1) gitexecdir='$(gitexec_instdir_SQ)' all
  	$(QUIET_SUBDIR0)gitk-git $(QUIET_SUBDIR1) all
 -endif
 -ifndef NO_PERL
 -	$(QUIET_SUBDIR0)perl $(QUIET_SUBDIR1) PERL_PATH='$(PERL_PATH_SQ)' prefix='$(prefix_SQ)' localedir='$(localedir_SQ)' all
  endif
  	$(QUIET_SUBDIR0)templates $(QUIET_SUBDIR1) SHELL_PATH='$(SHELL_PATH_SQ)' PERL_PATH='$(PERL_PATH_SQ)'
  
@@@ -1942,8 -1928,7 +1947,8 @@@ common-cmds.h: $(wildcard Documentation
  
  SCRIPT_DEFINES = $(SHELL_PATH_SQ):$(DIFF_SQ):$(GIT_VERSION):\
  	$(localedir_SQ):$(NO_CURL):$(USE_GETTEXT_SCHEME):$(SANE_TOOL_PATH_SQ):\
 -	$(gitwebdir_SQ):$(PERL_PATH_SQ):$(SANE_TEXT_GREP):$(PAGER_ENV)
 +	$(gitwebdir_SQ):$(PERL_PATH_SQ):$(SANE_TEXT_GREP):$(PAGER_ENV):\
 +	$(perllibdir_SQ)
  define cmd_munge_script
  $(RM) $@ $@+ && \
  sed -e '1s|#!.*/sh|#!$(SHELL_PATH_SQ)|' \
@@@ -1987,12 -1972,23 +1992,12 @@@ git.res: git.rc GIT-VERSION-FIL
  $(SCRIPT_PERL_GEN): GIT-BUILD-OPTIONS
  
  ifndef NO_PERL
 -$(SCRIPT_PERL_GEN): perl/perl.mak
 +$(SCRIPT_PERL_GEN):
  
 -perl/perl.mak: perl/PM.stamp
 -
 -perl/PM.stamp: FORCE
 -	@$(FIND) perl -type f -name '*.pm' | sort >$@+ && \
 -	$(PERL_PATH) -V >>$@+ && \
 -	{ cmp $@+ $@ >/dev/null 2>/dev/null || mv $@+ $@; } && \
 -	$(RM) $@+
 -
 -perl/perl.mak: GIT-CFLAGS GIT-PREFIX perl/Makefile perl/Makefile.PL
 -	$(QUIET_SUBDIR0)perl $(QUIET_SUBDIR1) PERL_PATH='$(PERL_PATH_SQ)' prefix='$(prefix_SQ)' $(@F)
 -
 -PERL_DEFINES = $(PERL_PATH_SQ):$(PERLLIB_EXTRA_SQ)
 -$(SCRIPT_PERL_GEN): % : %.perl perl/perl.mak GIT-PERL-DEFINES GIT-VERSION-FILE
 +PERL_DEFINES = $(PERL_PATH_SQ):$(PERLLIB_EXTRA_SQ):$(perllibdir_SQ)
 +$(SCRIPT_PERL_GEN): % : %.perl GIT-PERL-DEFINES GIT-VERSION-FILE
  	$(QUIET_GEN)$(RM) $@ $@+ && \
 -	INSTLIBDIR=`MAKEFLAGS= $(MAKE) -C perl -s --no-print-directory instlibdir` && \
 +	INSTLIBDIR='$(perllibdir_SQ)' && \
  	INSTLIBDIR_EXTRA='$(PERLLIB_EXTRA_SQ)' && \
  	INSTLIBDIR="$$INSTLIBDIR$${INSTLIBDIR_EXTRA:+:$$INSTLIBDIR_EXTRA}" && \
  	sed -e '1{' \
@@@ -2095,7 -2091,7 +2100,7 @@@ VCSSVN_OBJS += vcs-svn/fast_export.
  VCSSVN_OBJS += vcs-svn/svndiff.o
  VCSSVN_OBJS += vcs-svn/svndump.o
  
 -TEST_OBJS := $(patsubst %$X,%.o,$(TEST_PROGRAMS))
 +TEST_OBJS := $(patsubst %$X,%.o,$(TEST_PROGRAMS)) $(patsubst %,t/helper/%,$(TEST_BUILTINS_OBJS))
  OBJECTS := $(LIB_OBJS) $(BUILTIN_OBJS) $(PROGRAM_OBJS) $(TEST_OBJS) \
  	$(XDIFF_OBJS) \
  	$(VCSSVN_OBJS) \
@@@ -2180,8 -2176,6 +2185,8 @@@ gettext.sp gettext.s gettext.o: EXTRA_C
  http-push.sp http.sp http-walker.sp remote-curl.sp imap-send.sp: SPARSE_FLAGS += \
  	-DCURL_DISABLE_TYPECHECK
  
 +pack-revindex.sp: SPARSE_FLAGS += -Wno-memcpy-max-count
 +
  ifdef NO_EXPAT
  http-walker.sp http-walker.s http-walker.o: EXTRA_CPPFLAGS = -DNO_EXPAT
  endif
@@@ -2236,15 -2230,13 +2241,15 @@@ $(VCSSVN_LIB): $(VCSSVN_OBJS
  
  export DEFAULT_EDITOR DEFAULT_PAGER
  
 -.PHONY: doc man html info pdf
 -doc:
 +.PHONY: doc man man-perl html info pdf
 +doc: man-perl
  	$(MAKE) -C Documentation all
  
 -man:
 +man: man-perl
  	$(MAKE) -C Documentation man
  
 +man-perl: perl/build/man/man3/Git.3pm
 +
  html:
  	$(MAKE) -C Documentation html
  
@@@ -2320,29 -2312,6 +2325,29 @@@ endi
  po/build/locale/%/LC_MESSAGES/git.mo: po/%.po
  	$(QUIET_MSGFMT)mkdir -p $(dir $@) && $(MSGFMT) -o $@ $<
  
 +LIB_PERL := $(wildcard perl/Git.pm perl/Git/*.pm perl/Git/*/*.pm perl/Git/*/*/*.pm)
 +LIB_PERL_GEN := $(patsubst perl/%.pm,perl/build/lib/%.pm,$(LIB_PERL))
 +LIB_CPAN := $(wildcard perl/FromCPAN/*.pm perl/FromCPAN/*/*.pm)
 +LIB_CPAN_GEN := $(patsubst perl/%.pm,perl/build/lib/%.pm,$(LIB_CPAN))
 +
 +ifndef NO_PERL
 +all:: $(LIB_PERL_GEN)
 +ifndef NO_PERL_CPAN_FALLBACKS
 +all:: $(LIB_CPAN_GEN)
 +endif
 +NO_PERL_CPAN_FALLBACKS_SQ = $(subst ','\'',$(NO_PERL_CPAN_FALLBACKS))
 +endif
 +
 +perl/build/lib/%.pm: perl/%.pm
 +	$(QUIET_GEN)mkdir -p $(dir $@) && \
 +	sed -e 's|@@LOCALEDIR@@|$(localedir_SQ)|g' \
 +	    -e 's|@@NO_PERL_CPAN_FALLBACKS@@|$(NO_PERL_CPAN_FALLBACKS_SQ)|g' \
 +	< $< > $@
 +
 +perl/build/man/man3/Git.3pm: perl/Git.pm
 +	$(QUIET_GEN)mkdir -p $(dir $@) && \
 +	pod2man $< $@
 +
  FIND_SOURCE_FILES = ( \
  	git ls-files \
  		'*.[hcS]' \
@@@ -2406,7 -2375,6 +2411,7 @@@ GIT-LDFLAGS: FORC
  # and the first level quoting from the shell that runs "echo".
  GIT-BUILD-OPTIONS: FORCE
  	@echo SHELL_PATH=\''$(subst ','\'',$(SHELL_PATH_SQ))'\' >$@+
 +	@echo TEST_SHELL_PATH=\''$(subst ','\'',$(TEST_SHELL_PATH_SQ))'\' >>$@+
  	@echo PERL_PATH=\''$(subst ','\'',$(PERL_PATH_SQ))'\' >>$@+
  	@echo DIFF=\''$(subst ','\'',$(subst ','\'',$(DIFF)))'\' >>$@+
  	@echo PYTHON_PATH=\''$(subst ','\'',$(PYTHON_PATH_SQ))'\' >>$@+
@@@ -2506,12 -2474,10 +2511,12 @@@ t/helper/test-svn-fe$X: $(VCSSVN_LIB
  
  .PRECIOUS: $(TEST_OBJS)
  
 +t/helper/test-tool$X: $(patsubst %,t/helper/%,$(TEST_BUILTINS_OBJS))
 +
  t/helper/test-%$X: t/helper/test-%.o GIT-LDFLAGS $(GITLIBS)
  	$(QUIET_LINK)$(CC) $(ALL_CFLAGS) -o $@ $(ALL_LDFLAGS) $(filter %.o,$^) $(filter %.a,$^) $(LIBS)
  
 -check-sha1:: t/helper/test-sha1$X
 +check-sha1:: t/helper/test-tool$X
  	t/helper/test-sha1.sh
  
  SP_OBJ = $(patsubst %.o,%.sp,$(C_OBJ))
@@@ -2605,9 -2571,7 +2610,9 @@@ ifndef NO_GETTEX
  	(cd '$(DESTDIR_SQ)$(localedir_SQ)' && umask 022 && $(TAR) xof -)
  endif
  ifndef NO_PERL
 -	$(MAKE) -C perl prefix='$(prefix_SQ)' DESTDIR='$(DESTDIR_SQ)' install
 +	$(INSTALL) -d -m 755 '$(DESTDIR_SQ)$(perllibdir_SQ)'
 +	(cd perl/build/lib && $(TAR) cf - .) | \
 +	(cd '$(DESTDIR_SQ)$(perllibdir_SQ)' && umask 022 && $(TAR) xof -)
  	$(MAKE) -C gitweb install
  endif
  ifndef NO_TCLTK
@@@ -2620,63 -2584,49 +2625,63 @@@ endi
  
  	bindir=$$(cd '$(DESTDIR_SQ)$(bindir_SQ)' && pwd) && \
  	execdir=$$(cd '$(DESTDIR_SQ)$(gitexec_instdir_SQ)' && pwd) && \
 +	destdir_from_execdir_SQ=$$(echo '$(gitexecdir_relative_SQ)' | sed -e 's|[^/][^/]*|..|g') && \
  	{ test "$$bindir/" = "$$execdir/" || \
  	  for p in git$X $(filter $(install_bindir_programs),$(ALL_PROGRAMS)); do \
  		$(RM) "$$execdir/$$p" && \
 -		test -z "$(NO_INSTALL_HARDLINKS)$(NO_CROSS_DIRECTORY_HARDLINKS)" && \
 -		ln "$$bindir/$$p" "$$execdir/$$p" 2>/dev/null || \
 -		cp "$$bindir/$$p" "$$execdir/$$p" || exit; \
 +		test -n "$(INSTALL_SYMLINKS)" && \
 +		ln -s "$$destdir_from_execdir_SQ/$(bindir_relative_SQ)/$$p" "$$execdir/$$p" || \
 +		{ test -z "$(NO_INSTALL_HARDLINKS)$(NO_CROSS_DIRECTORY_HARDLINKS)" && \
 +		  ln "$$bindir/$$p" "$$execdir/$$p" 2>/dev/null || \
 +		  cp "$$bindir/$$p" "$$execdir/$$p" || exit; } \
  	  done; \
  	} && \
  	for p in $(filter $(install_bindir_programs),$(BUILT_INS)); do \
  		$(RM) "$$bindir/$$p" && \
 -		test -z "$(NO_INSTALL_HARDLINKS)" && \
 -		ln "$$bindir/git$X" "$$bindir/$$p" 2>/dev/null || \
 -		ln -s "git$X" "$$bindir/$$p" 2>/dev/null || \
 -		cp "$$bindir/git$X" "$$bindir/$$p" || exit; \
 +		test -n "$(INSTALL_SYMLINKS)" && \
 +		ln -s "git$X" "$$bindir/$$p" || \
 +		{ test -z "$(NO_INSTALL_HARDLINKS)" && \
 +		  ln "$$bindir/git$X" "$$bindir/$$p" 2>/dev/null || \
 +		  ln -s "git$X" "$$bindir/$$p" 2>/dev/null || \
 +		  cp "$$bindir/git$X" "$$bindir/$$p" || exit; } \
  	done && \
  	for p in $(BUILT_INS); do \
  		$(RM) "$$execdir/$$p" && \
 -		test -z "$(NO_INSTALL_HARDLINKS)" && \
 -		ln "$$execdir/git$X" "$$execdir/$$p" 2>/dev/null || \
 -		ln -s "git$X" "$$execdir/$$p" 2>/dev/null || \
 -		cp "$$execdir/git$X" "$$execdir/$$p" || exit; \
 +		test -n "$(INSTALL_SYMLINKS)" && \
 +		ln -s "$$destdir_from_execdir_SQ/$(bindir_relative_SQ)/git$X" "$$execdir/$$p" || \
 +		{ test -z "$(NO_INSTALL_HARDLINKS)" && \
 +		  ln "$$execdir/git$X" "$$execdir/$$p" 2>/dev/null || \
 +		  ln -s "git$X" "$$execdir/$$p" 2>/dev/null || \
 +		  cp "$$execdir/git$X" "$$execdir/$$p" || exit; } \
  	done && \
  	remote_curl_aliases="$(REMOTE_CURL_ALIASES)" && \
  	for p in $$remote_curl_aliases; do \
  		$(RM) "$$execdir/$$p" && \
 -		test -z "$(NO_INSTALL_HARDLINKS)" && \
 -		ln "$$execdir/git-remote-http$X" "$$execdir/$$p" 2>/dev/null || \
 -		ln -s "git-remote-http$X" "$$execdir/$$p" 2>/dev/null || \
 -		cp "$$execdir/git-remote-http$X" "$$execdir/$$p" || exit; \
 +		test -n "$(INSTALL_SYMLINKS)" && \
 +		ln -s "git-remote-http$X" "$$execdir/$$p" || \
 +		{ test -z "$(NO_INSTALL_HARDLINKS)" && \
 +		  ln "$$execdir/git-remote-http$X" "$$execdir/$$p" 2>/dev/null || \
 +		  ln -s "git-remote-http$X" "$$execdir/$$p" 2>/dev/null || \
 +		  cp "$$execdir/git-remote-http$X" "$$execdir/$$p" || exit; } \
  	done && \
  	./check_bindir "z$$bindir" "z$$execdir" "$$bindir/git-add$X"
  
 -.PHONY: install-gitweb install-doc install-man install-html install-info install-pdf
 +.PHONY: install-gitweb install-doc install-man install-man-perl install-html install-info install-pdf
  .PHONY: quick-install-doc quick-install-man quick-install-html
  install-gitweb:
  	$(MAKE) -C gitweb install
  
 -install-doc:
 +install-doc: install-man-perl
  	$(MAKE) -C Documentation install
  
 -install-man:
 +install-man: install-man-perl
  	$(MAKE) -C Documentation install-man
  
 +install-man-perl: man-perl
 +	$(INSTALL) -d -m 755 '$(DESTDIR_SQ)$(mandir_SQ)/man3'
 +	(cd perl/build/man/man3 && $(TAR) cf - .) | \
 +	(cd '$(DESTDIR_SQ)$(mandir_SQ)/man3' && umask 022 && $(TAR) xof -)
 +
  install-html:
  	$(MAKE) -C Documentation install-html
  
@@@ -2711,21 -2661,6 +2716,21 @@@ dist: git-archive$(X) configur
  		$(GIT_TARNAME)/configure \
  		$(GIT_TARNAME)/version \
  		$(GIT_TARNAME)/git-gui/version
 +ifdef DC_SHA1_SUBMODULE
 +	@mkdir -p $(GIT_TARNAME)/sha1collisiondetection/lib
 +	@cp sha1collisiondetection/LICENSE.txt \
 +		$(GIT_TARNAME)/sha1collisiondetection/
 +	@cp sha1collisiondetection/LICENSE.txt \
 +		$(GIT_TARNAME)/sha1collisiondetection/
 +	@cp sha1collisiondetection/lib/sha1.[ch] \
 +		$(GIT_TARNAME)/sha1collisiondetection/lib/
 +	@cp sha1collisiondetection/lib/ubc_check.[ch] \
 +		$(GIT_TARNAME)/sha1collisiondetection/lib/
 +	$(TAR) rf $(GIT_TARNAME).tar \
 +		$(GIT_TARNAME)/sha1collisiondetection/LICENSE.txt \
 +		$(GIT_TARNAME)/sha1collisiondetection/lib/sha1.[ch] \
 +		$(GIT_TARNAME)/sha1collisiondetection/lib/ubc_check.[ch]
 +endif
  	@$(RM) -r $(GIT_TARNAME)
  	gzip -f -9 $(GIT_TARNAME).tar
  
@@@ -2775,7 -2710,7 +2780,7 @@@ clean: profile-clean coverage-clea
  	$(RM) $(TEST_PROGRAMS) $(NO_INSTALL)
  	$(RM) -r bin-wrappers $(dep_dirs)
  	$(RM) -r po/build/
 -	$(RM) *.spec *.pyc *.pyo */*.pyc */*.pyo common-cmds.h $(ETAGS_TARGET) tags cscope*
 +	$(RM) *.pyc *.pyo */*.pyc */*.pyo common-cmds.h $(ETAGS_TARGET) tags cscope*
  	$(RM) -r $(GIT_TARNAME) .doc-tmp-dir
  	$(RM) $(GIT_TARNAME).tar.gz git-core_$(GIT_VERSION)-*.tar.gz
  	$(RM) $(htmldocs).tar.gz $(manpages).tar.gz
@@@ -2783,7 -2718,7 +2788,7 @@@
  	$(MAKE) -C Documentation/ clean
  ifndef NO_PERL
  	$(MAKE) -C gitweb clean
 -	$(MAKE) -C perl clean
 +	$(RM) -r perl/build/
  endif
  	$(MAKE) -C templates/ clean
  	$(MAKE) -C t/ clean
diff --combined builtin/clone.c
index 7df5932b85,4db3079acc..84f1473d19
--- a/builtin/clone.c
+++ b/builtin/clone.c
@@@ -26,8 -26,6 +26,8 @@@
  #include "run-command.h"
  #include "connected.h"
  #include "packfile.h"
 +#include "list-objects-filter-options.h"
 +#include "object-store.h"
  
  /*
   * Overall FIXMEs:
@@@ -62,7 -60,6 +62,7 @@@ static struct string_list option_option
  static int option_dissociate;
  static int max_jobs = -1;
  static struct string_list option_recurse_submodules = STRING_LIST_INIT_NODUP;
 +static struct list_objects_filter_options filter_options;
  
  static int recurse_submodules_cb(const struct option *opt,
  				 const char *arg, int unset)
@@@ -138,7 -135,6 +138,7 @@@ static struct option builtin_clone_opti
  			TRANSPORT_FAMILY_IPV4),
  	OPT_SET_INT('6', "ipv6", &family, N_("use IPv6 addresses only"),
  			TRANSPORT_FAMILY_IPV6),
 +	OPT_PARSE_LIST_OBJECTS_FILTER(&filter_options),
  	OPT_END()
  };
  
@@@ -477,9 -473,7 +477,9 @@@ static void clone_local(const char *src
  }
  
  static const char *junk_work_tree;
 +static int junk_work_tree_flags;
  static const char *junk_git_dir;
 +static int junk_git_dir_flags;
  static enum {
  	JUNK_LEAVE_NONE,
  	JUNK_LEAVE_REPO,
@@@ -508,12 -502,12 +508,12 @@@ static void remove_junk(void
  
  	if (junk_git_dir) {
  		strbuf_addstr(&sb, junk_git_dir);
 -		remove_dir_recursively(&sb, 0);
 +		remove_dir_recursively(&sb, junk_git_dir_flags);
  		strbuf_reset(&sb);
  	}
  	if (junk_work_tree) {
  		strbuf_addstr(&sb, junk_work_tree);
 -		remove_dir_recursively(&sb, 0);
 +		remove_dir_recursively(&sb, junk_work_tree_flags);
  	}
  	strbuf_release(&sb);
  }
@@@ -869,15 -863,10 +869,15 @@@ static void dissociate_from_references(
  	free(alternates);
  }
  
 +static int dir_exists(const char *path)
 +{
 +	struct stat sb;
 +	return !stat(path, &sb);
 +}
 +
  int cmd_clone(int argc, const char **argv, const char *prefix)
  {
  	int is_bundle = 0, is_local;
 -	struct stat buf;
  	const char *repo_name, *repo, *work_tree, *git_dir;
  	char *path, *dir;
  	int dest_exists;
@@@ -897,8 -886,6 +897,8 @@@
  	struct refspec *refspec;
  	const char *fetch_pattern;
  
 +	fetch_if_missing = 0;
 +
  	packet_trace_identity("clone");
  	argc = parse_options(argc, argv, prefix, builtin_clone_options,
  			     builtin_clone_usage, 0);
@@@ -951,7 -938,7 +951,7 @@@
  		dir = guess_dir_name(repo_name, is_bundle, option_bare);
  	strip_trailing_slashes(dir);
  
 -	dest_exists = !stat(dir, &buf);
 +	dest_exists = dir_exists(dir);
  	if (dest_exists && !is_empty_dir(dir))
  		die(_("destination path '%s' already exists and is not "
  			"an empty directory."), dir);
@@@ -962,7 -949,7 +962,7 @@@
  		work_tree = NULL;
  	else {
  		work_tree = getenv("GIT_WORK_TREE");
 -		if (work_tree && !stat(work_tree, &buf))
 +		if (work_tree && dir_exists(work_tree))
  			die(_("working tree '%s' already exists."), work_tree);
  	}
  
@@@ -980,24 -967,14 +980,24 @@@
  		if (safe_create_leading_directories_const(work_tree) < 0)
  			die_errno(_("could not create leading directories of '%s'"),
  				  work_tree);
 -		if (!dest_exists && mkdir(work_tree, 0777))
 +		if (dest_exists)
 +			junk_work_tree_flags |= REMOVE_DIR_KEEP_TOPLEVEL;
 +		else if (mkdir(work_tree, 0777))
  			die_errno(_("could not create work tree dir '%s'"),
  				  work_tree);
  		junk_work_tree = work_tree;
  		set_git_work_tree(work_tree);
  	}
  
 -	junk_git_dir = real_git_dir ? real_git_dir : git_dir;
 +	if (real_git_dir) {
 +		if (dir_exists(real_git_dir))
 +			junk_git_dir_flags |= REMOVE_DIR_KEEP_TOPLEVEL;
 +		junk_git_dir = real_git_dir;
 +	} else {
 +		if (dest_exists)
 +			junk_git_dir_flags |= REMOVE_DIR_KEEP_TOPLEVEL;
 +		junk_git_dir = git_dir;
 +	}
  	if (safe_create_leading_directories_const(git_dir) < 0)
  		die(_("could not create leading directories of '%s'"), git_dir);
  
@@@ -1096,8 -1073,6 +1096,8 @@@
  			warning(_("--shallow-since is ignored in local clones; use file:// instead."));
  		if (option_not.nr)
  			warning(_("--shallow-exclude is ignored in local clones; use file:// instead."));
 +		if (filter_options.choice)
 +			warning(_("--filter is ignored in local clones; use file:// instead."));
  		if (!access(mkpath("%s/shallow", path), F_OK)) {
  			if (option_local > 0)
  				warning(_("source repository is shallow, ignoring --local"));
@@@ -1126,16 -1101,10 +1126,16 @@@
  		transport_set_option(transport, TRANS_OPT_UPLOADPACK,
  				     option_upload_pack);
  
 -	if (transport->smart_options && !deepen)
 +	if (filter_options.choice) {
 +		transport_set_option(transport, TRANS_OPT_LIST_OBJECTS_FILTER,
 +				     filter_options.filter_spec);
 +		transport_set_option(transport, TRANS_OPT_FROM_PROMISOR, "1");
 +	}
 +
 +	if (transport->smart_options && !deepen && !filter_options.choice)
  		transport->smart_options->check_self_contained_and_connected = 1;
  
- 	refs = transport_get_remote_refs(transport);
+ 	refs = transport_get_remote_refs(transport, NULL);
  
  	if (refs) {
  		mapped_refs = wanted_peer_refs(refs, refspec);
@@@ -1192,17 -1161,13 +1192,17 @@@
  	write_refspec_config(src_ref_prefix, our_head_points_at,
  			remote_head_points_at, &branch_top);
  
 +	if (filter_options.choice)
 +		partial_clone_register("origin", &filter_options);
 +
  	if (is_local)
  		clone_local(path, git_dir);
  	else if (refs && complete_refs_before_fetch)
  		transport_fetch_refs(transport, mapped_refs);
  
  	update_remote_refs(refs, mapped_refs, remote_head_points_at,
 -			   branch_top.buf, reflog_msg.buf, transport, !is_local);
 +			   branch_top.buf, reflog_msg.buf, transport,
 +			   !is_local && !filter_options.choice);
  
  	update_head(our_head_points_at, remote_head, reflog_msg.buf);
  
@@@ -1218,12 -1183,11 +1218,12 @@@
  	transport_disconnect(transport);
  
  	if (option_dissociate) {
 -		close_all_packs();
 +		close_all_packs(the_repository->objects);
  		dissociate_from_references();
  	}
  
  	junk_mode = JUNK_LEAVE_REPO;
 +	fetch_if_missing = 1;
  	err = checkout(submodule_progress);
  
  	strbuf_release(&reflog_msg);
diff --combined builtin/fetch-pack.c
index a7bc1366ab,f9d7d0b5a5..1a1bc63566
--- a/builtin/fetch-pack.c
+++ b/builtin/fetch-pack.c
@@@ -4,6 -4,7 +4,7 @@@
  #include "remote.h"
  #include "connect.h"
  #include "sha1-array.h"
+ #include "protocol.h"
  
  static const char fetch_pack_usage[] =
  "git fetch-pack [--all] [--stdin] [--quiet | -q] [--keep | -k] [--thin] "
@@@ -52,9 -53,8 +53,10 @@@ int cmd_fetch_pack(int argc, const cha
  	struct fetch_pack_args args;
  	struct oid_array shallow = OID_ARRAY_INIT;
  	struct string_list deepen_not = STRING_LIST_INIT_DUP;
+ 	struct packet_reader reader;
  
 +	fetch_if_missing = 0;
 +
  	packet_trace_identity("fetch-pack");
  
  	memset(&args, 0, sizeof(args));
@@@ -145,22 -145,6 +147,22 @@@
  			args.update_shallow = 1;
  			continue;
  		}
 +		if (!strcmp("--from-promisor", arg)) {
 +			args.from_promisor = 1;
 +			continue;
 +		}
 +		if (!strcmp("--no-dependents", arg)) {
 +			args.no_dependents = 1;
 +			continue;
 +		}
 +		if (skip_prefix(arg, ("--" CL_ARG__FILTER "="), &arg)) {
 +			parse_list_objects_filter(&args.filter_options, arg);
 +			continue;
 +		}
 +		if (!strcmp(arg, ("--no-" CL_ARG__FILTER))) {
 +			list_objects_filter_set_no_filter(&args.filter_options);
 +			continue;
 +		}
  		usage(fetch_pack_usage);
  	}
  	if (deepen_not.nr)
@@@ -211,10 -195,24 +213,24 @@@
  		if (!conn)
  			return args.diag_url ? 0 : 1;
  	}
- 	get_remote_heads(fd[0], NULL, 0, &ref, 0, NULL, &shallow);
+ 
+ 	packet_reader_init(&reader, fd[0], NULL, 0,
+ 			   PACKET_READ_CHOMP_NEWLINE |
+ 			   PACKET_READ_GENTLE_ON_EOF);
+ 
+ 	switch (discover_version(&reader)) {
+ 	case protocol_v2:
+ 		die("support for protocol v2 not implemented yet");
+ 	case protocol_v1:
+ 	case protocol_v0:
+ 		get_remote_heads(&reader, &ref, 0, NULL, &shallow);
+ 		break;
+ 	case protocol_unknown_version:
+ 		BUG("unknown protocol version");
+ 	}
  
  	ref = fetch_pack(&args, fd, conn, ref, dest, sought, nr_sought,
- 			 &shallow, pack_lockfile_ptr);
+ 			 &shallow, pack_lockfile_ptr, protocol_v0);
  	if (pack_lockfile) {
  		printf("lock %s\n", pack_lockfile);
  		fflush(stdout);
diff --combined builtin/fetch.c
index dcdfc66f09,8258bbf950..7ee83ac0f8
--- a/builtin/fetch.c
+++ b/builtin/fetch.c
@@@ -19,7 -19,6 +19,7 @@@
  #include "argv-array.h"
  #include "utf8.h"
  #include "packfile.h"
 +#include "list-objects-filter-options.h"
  
  static const char * const builtin_fetch_usage[] = {
  	N_("git fetch [<options>] [<repository> [<refspec>...]]"),
@@@ -39,10 -38,6 +39,10 @@@ static int fetch_prune_config = -1; /* 
  static int prune = -1; /* unspecified */
  #define PRUNE_BY_DEFAULT 0 /* do we prune by default? */
  
 +static int fetch_prune_tags_config = -1; /* unspecified */
 +static int prune_tags = -1; /* unspecified */
 +#define PRUNE_TAGS_BY_DEFAULT 0 /* do we prune tags by default? */
 +
  static int all, append, dry_run, force, keep, multiple, update_head_ok, verbosity, deepen_relative;
  static int progress = -1;
  static int tags = TAGS_DEFAULT, unshallow, update_shallow, deepen;
@@@ -61,7 -56,6 +61,7 @@@ static int recurse_submodules_default 
  static int shown_url = 0;
  static int refmap_alloc, refmap_nr;
  static const char **refmap_array;
 +static struct list_objects_filter_options filter_options;
  
  static int git_fetch_config(const char *k, const char *v, void *cb)
  {
@@@ -70,11 -64,6 +70,11 @@@
  		return 0;
  	}
  
 +	if (!strcmp(k, "fetch.prunetags")) {
 +		fetch_prune_tags_config = git_config_bool(k, v);
 +		return 0;
 +	}
 +
  	if (!strcmp(k, "submodule.recurse")) {
  		int r = git_config_bool(k, v) ?
  			RECURSE_SUBMODULES_ON : RECURSE_SUBMODULES_OFF;
@@@ -126,7 -115,7 +126,7 @@@ static struct option builtin_fetch_opti
  		 N_("append to .git/FETCH_HEAD instead of overwriting")),
  	OPT_STRING(0, "upload-pack", &upload_pack, N_("path"),
  		   N_("path to upload pack on remote end")),
 -	OPT__FORCE(&force, N_("force overwrite of local branch")),
 +	OPT__FORCE(&force, N_("force overwrite of local branch"), 0),
  	OPT_BOOL('m', "multiple", &multiple,
  		 N_("fetch from multiple remotes")),
  	OPT_SET_INT('t', "tags", &tags,
@@@ -137,8 -126,6 +137,8 @@@
  		    N_("number of submodules fetched in parallel")),
  	OPT_BOOL('p', "prune", &prune,
  		 N_("prune remote-tracking branches no longer on remote")),
 +	OPT_BOOL('P', "prune-tags", &prune_tags,
 +		 N_("prune local tags no longer on remote and clobber changed tags")),
  	{ OPTION_CALLBACK, 0, "recurse-submodules", &recurse_submodules, N_("on-demand"),
  		    N_("control recursive fetching of submodules"),
  		    PARSE_OPT_OPTARG, option_fetch_parse_recurse_submodules },
@@@ -174,7 -161,6 +174,7 @@@
  			TRANSPORT_FAMILY_IPV4),
  	OPT_SET_INT('6', "ipv6", &family, N_("use IPv6 addresses only"),
  			TRANSPORT_FAMILY_IPV6),
 +	OPT_PARSE_LIST_OBJECTS_FILTER(&filter_options),
  	OPT_END()
  };
  
@@@ -264,7 -250,7 +264,7 @@@ static void find_non_local_tags(struct 
  	struct string_list_item *item = NULL;
  
  	for_each_ref(add_existing, &existing_refs);
- 	for (ref = transport_get_remote_refs(transport); ref; ref = ref->next) {
+ 	for (ref = transport_get_remote_refs(transport, NULL); ref; ref = ref->next) {
  		if (!starts_with(ref->name, "refs/tags/"))
  			continue;
  
@@@ -346,11 -332,28 +346,28 @@@ static struct ref *get_ref_map(struct t
  	struct ref *rm;
  	struct ref *ref_map = NULL;
  	struct ref **tail = &ref_map;
+ 	struct argv_array ref_prefixes = ARGV_ARRAY_INIT;
  
  	/* opportunistically-updated references: */
  	struct ref *orefs = NULL, **oref_tail = &orefs;
  
- 	const struct ref *remote_refs = transport_get_remote_refs(transport);
+ 	const struct ref *remote_refs;
+ 
+ 	for (i = 0; i < refspec_count; i++) {
+ 		if (!refspecs[i].exact_sha1) {
+ 			const char *glob = strchr(refspecs[i].src, '*');
+ 			if (glob)
+ 				argv_array_pushf(&ref_prefixes, "%.*s",
+ 						 (int)(glob - refspecs[i].src),
+ 						 refspecs[i].src);
+ 			else
+ 				expand_ref_prefix(&ref_prefixes, refspecs[i].src);
+ 		}
+ 	}
+ 
+ 	remote_refs = transport_get_remote_refs(transport, &ref_prefixes);
+ 
+ 	argv_array_clear(&ref_prefixes);
  
  	if (refspec_count) {
  		struct refspec *fetch_refspec;
@@@ -637,7 -640,7 +654,7 @@@ static int update_local_ref(struct ref 
  	struct branch *current_branch = branch_get(NULL);
  	const char *pretty_ref = prettify_refname(ref->name);
  
 -	type = sha1_object_info(ref->new_oid.hash, NULL);
 +	type = oid_object_info(&ref->new_oid, NULL);
  	if (type < 0)
  		die(_("object %s not found"), oid_to_hex(&ref->new_oid));
  
@@@ -708,9 -711,9 +725,9 @@@
  	if (in_merge_bases(current, updated)) {
  		struct strbuf quickref = STRBUF_INIT;
  		int r;
 -		strbuf_add_unique_abbrev(&quickref, current->object.oid.hash, DEFAULT_ABBREV);
 +		strbuf_add_unique_abbrev(&quickref, &current->object.oid, DEFAULT_ABBREV);
  		strbuf_addstr(&quickref, "..");
 -		strbuf_add_unique_abbrev(&quickref, ref->new_oid.hash, DEFAULT_ABBREV);
 +		strbuf_add_unique_abbrev(&quickref, &ref->new_oid, DEFAULT_ABBREV);
  		if ((recurse_submodules != RECURSE_SUBMODULES_OFF) &&
  		    (recurse_submodules != RECURSE_SUBMODULES_ON))
  			check_for_new_submodule_commits(&ref->new_oid);
@@@ -723,9 -726,9 +740,9 @@@
  	} else if (force || ref->force) {
  		struct strbuf quickref = STRBUF_INIT;
  		int r;
 -		strbuf_add_unique_abbrev(&quickref, current->object.oid.hash, DEFAULT_ABBREV);
 +		strbuf_add_unique_abbrev(&quickref, &current->object.oid, DEFAULT_ABBREV);
  		strbuf_addstr(&quickref, "...");
 -		strbuf_add_unique_abbrev(&quickref, ref->new_oid.hash, DEFAULT_ABBREV);
 +		strbuf_add_unique_abbrev(&quickref, &ref->new_oid, DEFAULT_ABBREV);
  		if ((recurse_submodules != RECURSE_SUBMODULES_OFF) &&
  		    (recurse_submodules != RECURSE_SUBMODULES_ON))
  			check_for_new_submodule_commits(&ref->new_oid);
@@@ -1059,11 -1062,6 +1076,11 @@@ static struct transport *prepare_transp
  		set_option(transport, TRANS_OPT_DEEPEN_RELATIVE, "yes");
  	if (update_shallow)
  		set_option(transport, TRANS_OPT_UPDATE_SHALLOW, "yes");
 +	if (filter_options.choice) {
 +		set_option(transport, TRANS_OPT_LIST_OBJECTS_FILTER,
 +			   filter_options.filter_spec);
 +		set_option(transport, TRANS_OPT_FROM_PROMISOR, "1");
 +	}
  	return transport;
  }
  
@@@ -1231,8 -1229,6 +1248,8 @@@ static void add_options_to_argv(struct 
  		argv_array_push(argv, "--dry-run");
  	if (prune != -1)
  		argv_array_push(argv, prune ? "--prune" : "--no-prune");
 +	if (prune_tags != -1)
 +		argv_array_push(argv, prune_tags ? "--prune-tags" : "--no-prune-tags");
  	if (update_head_ok)
  		argv_array_push(argv, "--update-head-ok");
  	if (force)
@@@ -1286,65 -1282,12 +1303,65 @@@ static int fetch_multiple(struct string
  	return result;
  }
  
 -static int fetch_one(struct remote *remote, int argc, const char **argv)
 +/*
 + * Fetching from the promisor remote should use the given filter-spec
 + * or inherit the default filter-spec from the config.
 + */
 +static inline void fetch_one_setup_partial(struct remote *remote)
 +{
 +	/*
 +	 * Explicit --no-filter argument overrides everything, regardless
 +	 * of any prior partial clones and fetches.
 +	 */
 +	if (filter_options.no_filter)
 +		return;
 +
 +	/*
 +	 * If no prior partial clone/fetch and the current fetch DID NOT
 +	 * request a partial-fetch, do a normal fetch.
 +	 */
 +	if (!repository_format_partial_clone && !filter_options.choice)
 +		return;
 +
 +	/*
 +	 * If this is the FIRST partial-fetch request, we enable partial
 +	 * on this repo and remember the given filter-spec as the default
 +	 * for subsequent fetches to this remote.
 +	 */
 +	if (!repository_format_partial_clone && filter_options.choice) {
 +		partial_clone_register(remote->name, &filter_options);
 +		return;
 +	}
 +
 +	/*
 +	 * We are currently limited to only ONE promisor remote and only
 +	 * allow partial-fetches from the promisor remote.
 +	 */
 +	if (strcmp(remote->name, repository_format_partial_clone)) {
 +		if (filter_options.choice)
 +			die(_("--filter can only be used with the remote configured in core.partialClone"));
 +		return;
 +	}
 +
 +	/*
 +	 * Do a partial-fetch from the promisor remote using either the
 +	 * explicitly given filter-spec or inherit the filter-spec from
 +	 * the config.
 +	 */
 +	if (!filter_options.choice)
 +		partial_clone_get_default_filter_spec(&filter_options);
 +	return;
 +}
 +
 +static int fetch_one(struct remote *remote, int argc, const char **argv, int prune_tags_ok)
  {
  	static const char **refs = NULL;
  	struct refspec *refspec;
  	int ref_nr = 0;
 +	int j = 0;
  	int exit_code;
 +	int maybe_prune_tags;
 +	int remote_via_config = remote_is_configured(remote, 0);
  
  	if (!remote)
  		die(_("No remote repository specified.  Please, specify either a URL or a\n"
@@@ -1354,39 -1297,18 +1371,39 @@@
  
  	if (prune < 0) {
  		/* no command line request */
 -		if (0 <= gtransport->remote->prune)
 -			prune = gtransport->remote->prune;
 +		if (0 <= remote->prune)
 +			prune = remote->prune;
  		else if (0 <= fetch_prune_config)
  			prune = fetch_prune_config;
  		else
  			prune = PRUNE_BY_DEFAULT;
  	}
  
 +	if (prune_tags < 0) {
 +		/* no command line request */
 +		if (0 <= remote->prune_tags)
 +			prune_tags = remote->prune_tags;
 +		else if (0 <= fetch_prune_tags_config)
 +			prune_tags = fetch_prune_tags_config;
 +		else
 +			prune_tags = PRUNE_TAGS_BY_DEFAULT;
 +	}
 +
 +	maybe_prune_tags = prune_tags_ok && prune_tags;
 +	if (maybe_prune_tags && remote_via_config)
 +		add_prune_tags_to_fetch_refspec(remote);
 +
 +	if (argc > 0 || (maybe_prune_tags && !remote_via_config)) {
 +		size_t nr_alloc = st_add3(argc, maybe_prune_tags, 1);
 +		refs = xcalloc(nr_alloc, sizeof(const char *));
 +		if (maybe_prune_tags) {
 +			refs[j++] = xstrdup("refs/tags/*:refs/tags/*");
 +			ref_nr++;
 +		}
 +	}
 +
  	if (argc > 0) {
 -		int j = 0;
  		int i;
 -		refs = xcalloc(st_add(argc, 1), sizeof(const char *));
  		for (i = 0; i < argc; i++) {
  			if (!strcmp(argv[i], "tag")) {
  				i++;
@@@ -1396,8 -1318,9 +1413,8 @@@
  						    argv[i], argv[i]);
  			} else
  				refs[j++] = argv[i];
 +			ref_nr++;
  		}
 -		refs[j] = NULL;
 -		ref_nr = j;
  	}
  
  	sigchain_push_common(unlock_pack_on_signal);
@@@ -1414,15 -1337,12 +1431,15 @@@ int cmd_fetch(int argc, const char **ar
  {
  	int i;
  	struct string_list list = STRING_LIST_INIT_DUP;
 -	struct remote *remote;
 +	struct remote *remote = NULL;
  	int result = 0;
 +	int prune_tags_ok = 1;
  	struct argv_array argv_gc_auto = ARGV_ARRAY_INIT;
  
  	packet_trace_identity("fetch");
  
 +	fetch_if_missing = 0;
 +
  	/* Record the command line for the reflog */
  	strbuf_addstr(&default_rla, "fetch");
  	for (i = 1; i < argc; i++)
@@@ -1456,23 -1376,23 +1473,23 @@@
  	if (depth || deepen_since || deepen_not.nr)
  		deepen = 1;
  
 +	if (filter_options.choice && !repository_format_partial_clone)
 +		die("--filter can only be used when extensions.partialClone is set");
 +
  	if (all) {
  		if (argc == 1)
  			die(_("fetch --all does not take a repository argument"));
  		else if (argc > 1)
  			die(_("fetch --all does not make sense with refspecs"));
  		(void) for_each_remote(get_one_remote_for_fetch, &list);
 -		result = fetch_multiple(&list);
  	} else if (argc == 0) {
  		/* No arguments -- use default remote */
  		remote = remote_get(NULL);
 -		result = fetch_one(remote, argc, argv);
  	} else if (multiple) {
  		/* All arguments are assumed to be remotes or groups */
  		for (i = 0; i < argc; i++)
  			if (!add_remote_or_group(argv[i], &list))
  				die(_("No such remote or remote group: %s"), argv[i]);
 -		result = fetch_multiple(&list);
  	} else {
  		/* Single remote or group */
  		(void) add_remote_or_group(argv[0], &list);
@@@ -1480,26 -1400,14 +1497,26 @@@
  			/* More than one remote */
  			if (argc > 1)
  				die(_("Fetching a group and specifying refspecs does not make sense"));
 -			result = fetch_multiple(&list);
  		} else {
  			/* Zero or one remotes */
  			remote = remote_get(argv[0]);
 -			result = fetch_one(remote, argc-1, argv+1);
 +			prune_tags_ok = (argc == 1);
 +			argc--;
 +			argv++;
  		}
  	}
  
 +	if (remote) {
 +		if (filter_options.choice || repository_format_partial_clone)
 +			fetch_one_setup_partial(remote);
 +		result = fetch_one(remote, argc, argv, prune_tags_ok);
 +	} else {
 +		if (filter_options.choice)
 +			die(_("--filter can only be used with the remote configured in core.partialClone"));
 +		/* TODO should this also die if we have a previous partial-clone? */
 +		result = fetch_multiple(&list);
 +	}
 +
  	if (!result && (recurse_submodules != RECURSE_SUBMODULES_OFF)) {
  		struct argv_array options = ARGV_ARRAY_INIT;
  
@@@ -1516,7 -1424,7 +1533,7 @@@
  
  	string_list_clear(&list, 0);
  
 -	close_all_packs();
 +	close_all_packs(the_repository->objects);
  
  	argv_array_pushl(&argv_gc_auto, "gc", "--auto", NULL);
  	if (verbosity < 0)
diff --combined builtin/ls-remote.c
index 540d56429f,4276bf97d5..380c180270
--- a/builtin/ls-remote.c
+++ b/builtin/ls-remote.c
@@@ -2,6 -2,7 +2,7 @@@
  #include "cache.h"
  #include "transport.h"
  #include "remote.h"
+ #include "refs.h"
  
  static const char * const ls_remote_usage[] = {
  	N_("git ls-remote [--heads] [--tags] [--refs] [--upload-pack=<exec>]\n"
@@@ -43,6 -44,7 +44,7 @@@ int cmd_ls_remote(int argc, const char 
  	int show_symref_target = 0;
  	const char *uploadpack = NULL;
  	const char **pattern = NULL;
+ 	struct argv_array ref_prefixes = ARGV_ARRAY_INIT;
  
  	struct remote *remote;
  	struct transport *transport;
@@@ -60,9 -62,8 +62,9 @@@
  		OPT_BIT(0, "refs", &flags, N_("do not show peeled tags"), REF_NORMAL),
  		OPT_BOOL(0, "get-url", &get_url,
  			 N_("take url.<base>.insteadOf into account")),
 -		OPT_SET_INT(0, "exit-code", &status,
 -			    N_("exit with exit code 2 if no matching refs are found"), 2),
 +		OPT_SET_INT_F(0, "exit-code", &status,
 +			      N_("exit with exit code 2 if no matching refs are found"),
 +			      2, PARSE_OPT_NOCOMPLETE),
  		OPT_BOOL(0, "symref", &show_symref_target,
  			 N_("show underlying ref in addition to the object pointed by it")),
  		OPT_END()
@@@ -75,8 -76,17 +77,17 @@@
  	if (argc > 1) {
  		int i;
  		pattern = xcalloc(argc, sizeof(const char *));
- 		for (i = 1; i < argc; i++)
+ 		for (i = 1; i < argc; i++) {
+ 			const char *glob;
  			pattern[i - 1] = xstrfmt("*/%s", argv[i]);
+ 
+ 			glob = strchr(argv[i], '*');
+ 			if (glob)
+ 				argv_array_pushf(&ref_prefixes, "%.*s",
+ 						 (int)(glob - argv[i]), argv[i]);
+ 			else
+ 				expand_ref_prefix(&ref_prefixes, argv[i]);
+ 		}
  	}
  
  	remote = remote_get(dest);
@@@ -97,7 -107,7 +108,7 @@@
  	if (uploadpack != NULL)
  		transport_set_option(transport, TRANS_OPT_UPLOADPACK, uploadpack);
  
- 	ref = transport_get_remote_refs(transport);
+ 	ref = transport_get_remote_refs(transport, &ref_prefixes);
  	if (transport_disconnect(transport))
  		return 1;
  
diff --combined builtin/receive-pack.c
index c4272fbc96,3656e94fdb..4fadf7e41e
--- a/builtin/receive-pack.c
+++ b/builtin/receive-pack.c
@@@ -1,5 -1,4 +1,5 @@@
  #include "builtin.h"
 +#include "repository.h"
  #include "config.h"
  #include "lockfile.h"
  #include "pack.h"
@@@ -70,7 -69,7 +70,7 @@@ static int sent_capabilities
  static int shallow_update;
  static const char *alt_shallow_file;
  static struct strbuf push_cert = STRBUF_INIT;
 -static unsigned char push_cert_sha1[20];
 +static struct object_id push_cert_oid;
  static struct signature_check sigcheck;
  static const char *push_cert_nonce;
  static const char *cert_nonce_seed;
@@@ -634,9 -633,8 +634,9 @@@ static void prepare_push_cert_sha1(stru
  		int bogs /* beginning_of_gpg_sig */;
  
  		already_done = 1;
 -		if (write_sha1_file(push_cert.buf, push_cert.len, "blob", push_cert_sha1))
 -			hashclr(push_cert_sha1);
 +		if (write_object_file(push_cert.buf, push_cert.len, "blob",
 +				      &push_cert_oid))
 +			oidclr(&push_cert_oid);
  
  		memset(&sigcheck, '\0', sizeof(sigcheck));
  		sigcheck.result = 'N';
@@@ -657,9 -655,9 +657,9 @@@
  		strbuf_release(&gpg_status);
  		nonce_status = check_nonce(push_cert.buf, bogs);
  	}
 -	if (!is_null_sha1(push_cert_sha1)) {
 +	if (!is_null_oid(&push_cert_oid)) {
  		argv_array_pushf(&proc->env_array, "GIT_PUSH_CERT=%s",
 -				 sha1_to_hex(push_cert_sha1));
 +				 oid_to_hex(&push_cert_oid));
  		argv_array_pushf(&proc->env_array, "GIT_PUSH_CERT_SIGNER=%s",
  				 sigcheck.signer ? sigcheck.signer : "");
  		argv_array_pushf(&proc->env_array, "GIT_PUSH_CERT_KEY=%s",
@@@ -1243,11 -1241,11 +1243,11 @@@ static void check_aliased_update(struc
  	rp_error("refusing inconsistent update between symref '%s' (%s..%s) and"
  		 " its target '%s' (%s..%s)",
  		 cmd->ref_name,
 -		 find_unique_abbrev(cmd->old_oid.hash, DEFAULT_ABBREV),
 -		 find_unique_abbrev(cmd->new_oid.hash, DEFAULT_ABBREV),
 +		 find_unique_abbrev(&cmd->old_oid, DEFAULT_ABBREV),
 +		 find_unique_abbrev(&cmd->new_oid, DEFAULT_ABBREV),
  		 dst_cmd->ref_name,
 -		 find_unique_abbrev(dst_cmd->old_oid.hash, DEFAULT_ABBREV),
 -		 find_unique_abbrev(dst_cmd->new_oid.hash, DEFAULT_ABBREV));
 +		 find_unique_abbrev(&dst_cmd->old_oid, DEFAULT_ABBREV),
 +		 find_unique_abbrev(&dst_cmd->new_oid, DEFAULT_ABBREV));
  
  	cmd->error_string = dst_cmd->error_string =
  		"inconsistent aliased update";
@@@ -1779,7 -1777,7 +1779,7 @@@ static const char *unpack(int err_fd, s
  		status = finish_command(&child);
  		if (status)
  			return "index-pack abnormal exit";
 -		reprepare_packed_git();
 +		reprepare_packed_git(the_repository);
  	}
  	return NULL;
  }
@@@ -1965,6 -1963,12 +1965,12 @@@ int cmd_receive_pack(int argc, const ch
  		unpack_limit = receive_unpack_limit;
  
  	switch (determine_protocol_version_server()) {
+ 	case protocol_v2:
+ 		/*
+ 		 * push support for protocol v2 has not been implemented yet,
+ 		 * so ignore the request to use v2 and fallback to using v0.
+ 		 */
+ 		break;
  	case protocol_v1:
  		/*
  		 * v1 is just the original protocol with a version string,
@@@ -2028,7 -2032,7 +2034,7 @@@
  			proc.git_cmd = 1;
  			proc.argv = argv_gc_auto;
  
 -			close_all_packs();
 +			close_all_packs(the_repository->objects);
  			if (!start_command(&proc)) {
  				if (use_sideband)
  					copy_to_sideband(proc.err, -1, NULL);
diff --combined builtin/remote.c
index 805ffc05cd,d0b6ff6e29..8708e584e9
--- a/builtin/remote.c
+++ b/builtin/remote.c
@@@ -168,7 -168,7 +168,7 @@@ static int add(int argc, const char **a
  		OPT_STRING('m', "master", &master, N_("branch"), N_("master branch")),
  		{ OPTION_CALLBACK, 0, "mirror", &mirror, N_("push|fetch"),
  			N_("set up remote as a mirror to push to or fetch from"),
 -			PARSE_OPT_OPTARG, parse_mirror_opt },
 +			PARSE_OPT_OPTARG | PARSE_OPT_COMP_ARG, parse_mirror_opt },
  		OPT_END()
  	};
  
@@@ -322,7 -322,7 +322,7 @@@ static void read_branches(void
  
  struct ref_states {
  	struct remote *remote;
 -	struct string_list new, stale, tracked, heads, push;
 +	struct string_list new_refs, stale, tracked, heads, push;
  	int queried;
  };
  
@@@ -337,12 -337,12 +337,12 @@@ static int get_ref_states(const struct 
  			die(_("Could not get fetch map for refspec %s"),
  				states->remote->fetch_refspec[i]);
  
 -	states->new.strdup_strings = 1;
 +	states->new_refs.strdup_strings = 1;
  	states->tracked.strdup_strings = 1;
  	states->stale.strdup_strings = 1;
  	for (ref = fetch_map; ref; ref = ref->next) {
  		if (!ref->peer_ref || !ref_exists(ref->peer_ref->name))
 -			string_list_append(&states->new, abbrev_branch(ref->name));
 +			string_list_append(&states->new_refs, abbrev_branch(ref->name));
  		else
  			string_list_append(&states->tracked, abbrev_branch(ref->name));
  	}
@@@ -356,7 -356,7 +356,7 @@@
  	free_refs(stale_refs);
  	free_refs(fetch_map);
  
 -	string_list_sort(&states->new);
 +	string_list_sort(&states->new_refs);
  	string_list_sort(&states->tracked);
  	string_list_sort(&states->stale);
  
@@@ -546,8 -546,8 +546,8 @@@ static int add_branch_for_removal(cons
  }
  
  struct rename_info {
 -	const char *old;
 -	const char *new;
 +	const char *old_name;
 +	const char *new_name;
  	struct string_list *remote_branches;
  };
  
@@@ -560,7 -560,7 +560,7 @@@ static int read_remote_branches(const c
  	int flag;
  	const char *symref;
  
 -	strbuf_addf(&buf, "refs/remotes/%s/", rename->old);
 +	strbuf_addf(&buf, "refs/remotes/%s/", rename->old_name);
  	if (starts_with(refname, buf.buf)) {
  		item = string_list_append(rename->remote_branches, xstrdup(refname));
  		symref = resolve_ref_unsafe(refname, RESOLVE_REF_READING,
@@@ -615,36 -615,36 +615,36 @@@ static int mv(int argc, const char **ar
  	if (argc != 3)
  		usage_with_options(builtin_remote_rename_usage, options);
  
 -	rename.old = argv[1];
 -	rename.new = argv[2];
 +	rename.old_name = argv[1];
 +	rename.new_name = argv[2];
  	rename.remote_branches = &remote_branches;
  
 -	oldremote = remote_get(rename.old);
 +	oldremote = remote_get(rename.old_name);
  	if (!remote_is_configured(oldremote, 1))
 -		die(_("No such remote: %s"), rename.old);
 +		die(_("No such remote: %s"), rename.old_name);
  
 -	if (!strcmp(rename.old, rename.new) && oldremote->origin != REMOTE_CONFIG)
 +	if (!strcmp(rename.old_name, rename.new_name) && oldremote->origin != REMOTE_CONFIG)
  		return migrate_file(oldremote);
  
 -	newremote = remote_get(rename.new);
 +	newremote = remote_get(rename.new_name);
  	if (remote_is_configured(newremote, 1))
 -		die(_("remote %s already exists."), rename.new);
 +		die(_("remote %s already exists."), rename.new_name);
  
 -	strbuf_addf(&buf, "refs/heads/test:refs/remotes/%s/test", rename.new);
 +	strbuf_addf(&buf, "refs/heads/test:refs/remotes/%s/test", rename.new_name);
  	if (!valid_fetch_refspec(buf.buf))
 -		die(_("'%s' is not a valid remote name"), rename.new);
 +		die(_("'%s' is not a valid remote name"), rename.new_name);
  
  	strbuf_reset(&buf);
 -	strbuf_addf(&buf, "remote.%s", rename.old);
 -	strbuf_addf(&buf2, "remote.%s", rename.new);
 +	strbuf_addf(&buf, "remote.%s", rename.old_name);
 +	strbuf_addf(&buf2, "remote.%s", rename.new_name);
  	if (git_config_rename_section(buf.buf, buf2.buf) < 1)
  		return error(_("Could not rename config section '%s' to '%s'"),
  				buf.buf, buf2.buf);
  
  	strbuf_reset(&buf);
 -	strbuf_addf(&buf, "remote.%s.fetch", rename.new);
 +	strbuf_addf(&buf, "remote.%s.fetch", rename.new_name);
  	git_config_set_multivar(buf.buf, NULL, NULL, 1);
 -	strbuf_addf(&old_remote_context, ":refs/remotes/%s/", rename.old);
 +	strbuf_addf(&old_remote_context, ":refs/remotes/%s/", rename.old_name);
  	for (i = 0; i < oldremote->fetch_refspec_nr; i++) {
  		char *ptr;
  
@@@ -655,8 -655,8 +655,8 @@@
  			refspec_updated = 1;
  			strbuf_splice(&buf2,
  				      ptr-buf2.buf + strlen(":refs/remotes/"),
 -				      strlen(rename.old), rename.new,
 -				      strlen(rename.new));
 +				      strlen(rename.old_name), rename.new_name,
 +				      strlen(rename.new_name));
  		} else
  			warning(_("Not updating non-default fetch refspec\n"
  				  "\t%s\n"
@@@ -670,10 -670,10 +670,10 @@@
  	for (i = 0; i < branch_list.nr; i++) {
  		struct string_list_item *item = branch_list.items + i;
  		struct branch_info *info = item->util;
 -		if (info->remote_name && !strcmp(info->remote_name, rename.old)) {
 +		if (info->remote_name && !strcmp(info->remote_name, rename.old_name)) {
  			strbuf_reset(&buf);
  			strbuf_addf(&buf, "branch.%s.remote", item->string);
 -			git_config_set(buf.buf, rename.new);
 +			git_config_set(buf.buf, rename.new_name);
  		}
  	}
  
@@@ -703,8 -703,8 +703,8 @@@
  			continue;
  		strbuf_reset(&buf);
  		strbuf_addstr(&buf, item->string);
 -		strbuf_splice(&buf, strlen("refs/remotes/"), strlen(rename.old),
 -				rename.new, strlen(rename.new));
 +		strbuf_splice(&buf, strlen("refs/remotes/"), strlen(rename.old_name),
 +				rename.new_name, strlen(rename.new_name));
  		strbuf_reset(&buf2);
  		strbuf_addf(&buf2, "remote: renamed %s to %s",
  				item->string, buf.buf);
@@@ -718,12 -718,12 +718,12 @@@
  			continue;
  		strbuf_reset(&buf);
  		strbuf_addstr(&buf, item->string);
 -		strbuf_splice(&buf, strlen("refs/remotes/"), strlen(rename.old),
 -				rename.new, strlen(rename.new));
 +		strbuf_splice(&buf, strlen("refs/remotes/"), strlen(rename.old_name),
 +				rename.new_name, strlen(rename.new_name));
  		strbuf_reset(&buf2);
  		strbuf_addstr(&buf2, item->util);
 -		strbuf_splice(&buf2, strlen("refs/remotes/"), strlen(rename.old),
 -				rename.new, strlen(rename.new));
 +		strbuf_splice(&buf2, strlen("refs/remotes/"), strlen(rename.old_name),
 +				rename.new_name, strlen(rename.new_name));
  		strbuf_reset(&buf3);
  		strbuf_addf(&buf3, "remote: renamed %s to %s",
  				item->string, buf.buf);
@@@ -822,7 -822,7 +822,7 @@@ static void clear_push_info(void *util
  
  static void free_remote_ref_states(struct ref_states *states)
  {
 -	string_list_clear(&states->new, 0);
 +	string_list_clear(&states->new_refs, 0);
  	string_list_clear(&states->stale, 1);
  	string_list_clear(&states->tracked, 0);
  	string_list_clear(&states->heads, 0);
@@@ -862,7 -862,7 +862,7 @@@ static int get_remote_ref_states(const 
  	if (query) {
  		transport = transport_get(states->remote, states->remote->url_nr > 0 ?
  			states->remote->url[0] : NULL);
- 		remote_refs = transport_get_remote_refs(transport);
+ 		remote_refs = transport_get_remote_refs(transport, NULL);
  		transport_disconnect(transport);
  
  		states->queried = 1;
@@@ -907,7 -907,7 +907,7 @@@ static int show_remote_info_item(struc
  	if (states->queried) {
  		const char *fmt = "%s";
  		const char *arg = "";
 -		if (string_list_has_string(&states->new, name)) {
 +		if (string_list_has_string(&states->new_refs, name)) {
  			fmt = _(" new (next fetch will store in remotes/%s)");
  			arg = states->remote->name;
  		} else if (string_list_has_string(&states->tracked, name))
@@@ -1176,7 -1176,7 +1176,7 @@@ static int show(int argc, const char **
  
  		/* remote branch info */
  		info.width = 0;
 -		for_each_string_list(&states.new, add_remote_to_show_info, &info);
 +		for_each_string_list(&states.new_refs, add_remote_to_show_info, &info);
  		for_each_string_list(&states.tracked, add_remote_to_show_info, &info);
  		for_each_string_list(&states.stale, add_remote_to_show_info, &info);
  		if (info.list->nr)
diff --combined fetch-pack.c
index adc1b68dd3,837e1fd21d..216d1368be
--- a/fetch-pack.c
+++ b/fetch-pack.c
@@@ -1,5 -1,4 +1,5 @@@
  #include "cache.h"
 +#include "repository.h"
  #include "config.h"
  #include "lockfile.h"
  #include "refs.h"
@@@ -30,7 -29,6 +30,7 @@@ static int deepen_not_ok
  static int fetch_fsck_objects = -1;
  static int transfer_fsck_objects = -1;
  static int agent_supported;
 +static int server_supports_filtering;
  static struct lock_file shallow_lock;
  static const char *alternate_shallow_file;
  
@@@ -262,8 -260,8 +262,8 @@@ static enum ack_type get_ack(int fd, st
  	char *line = packet_read_line(fd, &len);
  	const char *arg;
  
 -	if (!len)
 -		die(_("git fetch-pack: expected ACK/NAK, got EOF"));
 +	if (!line)
 +		die(_("git fetch-pack: expected ACK/NAK, got a flush packet"));
  	if (!strcmp(line, "NAK"))
  		return NAK;
  	if (skip_prefix(line, "ACK ", &arg)) {
@@@ -305,9 -303,9 +305,9 @@@ static void insert_one_alternate_object
  #define PIPESAFE_FLUSH 32
  #define LARGE_FLUSH 16384
  
- static int next_flush(struct fetch_pack_args *args, int count)
+ static int next_flush(int stateless_rpc, int count)
  {
- 	if (args->stateless_rpc) {
+ 	if (stateless_rpc) {
  		if (count < LARGE_FLUSH)
  			count <<= 1;
  		else
@@@ -381,8 -379,6 +381,8 @@@ static int find_common(struct fetch_pac
  			if (deepen_not_ok)      strbuf_addstr(&c, " deepen-not");
  			if (agent_supported)    strbuf_addf(&c, " agent=%s",
  							    git_user_agent_sanitized());
 +			if (args->filter_options.choice)
 +				strbuf_addstr(&c, " filter");
  			packet_buf_write(&req_buf, "want %s%s\n", remote_hex, c.buf);
  			strbuf_release(&c);
  		} else
@@@ -411,9 -407,6 +411,9 @@@
  			packet_buf_write(&req_buf, "deepen-not %s", s->string);
  		}
  	}
 +	if (server_supports_filtering && args->filter_options.choice)
 +		packet_buf_write(&req_buf, "filter %s",
 +				 args->filter_options.filter_spec);
  	packet_buf_flush(&req_buf);
  	state_len = req_buf.len;
  
@@@ -457,8 -450,6 +457,8 @@@
  
  	flushes = 0;
  	retval = -1;
 +	if (args->no_dependents)
 +		goto done;
  	while ((oid = get_rev())) {
  		packet_buf_write(&req_buf, "have %s\n", oid_to_hex(oid));
  		print_verbose(args, "have %s", oid_to_hex(oid));
@@@ -470,7 -461,7 +470,7 @@@
  			send_request(args, fd[1], &req_buf);
  			strbuf_setlen(&req_buf, state_len);
  			flushes++;
- 			flush_at = next_flush(args, count);
+ 			flush_at = next_flush(args->stateless_rpc, count);
  
  			/*
  			 * We keep one window "ahead" of the other side, and
@@@ -712,61 -703,23 +712,61 @@@ static void mark_alternate_complete(str
  	mark_complete(&obj->oid);
  }
  
 +struct loose_object_iter {
 +	struct oidset *loose_object_set;
 +	struct ref *refs;
 +};
 +
 +/*
 + *  If the number of refs is not larger than the number of loose objects,
 + *  this function stops inserting.
 + */
 +static int add_loose_objects_to_set(const struct object_id *oid,
 +				    const char *path,
 +				    void *data)
 +{
 +	struct loose_object_iter *iter = data;
 +	oidset_insert(iter->loose_object_set, oid);
 +	if (iter->refs == NULL)
 +		return 1;
 +
 +	iter->refs = iter->refs->next;
 +	return 0;
 +}
 +
  static int everything_local(struct fetch_pack_args *args,
  			    struct ref **refs,
  			    struct ref **sought, int nr_sought)
  {
  	struct ref *ref;
  	int retval;
 +	int old_save_commit_buffer = save_commit_buffer;
  	timestamp_t cutoff = 0;
 +	struct oidset loose_oid_set = OIDSET_INIT;
 +	int use_oidset = 0;
 +	struct loose_object_iter iter = {&loose_oid_set, *refs};
 +
 +	/* Enumerate all loose objects or know refs are not so many. */
 +	use_oidset = !for_each_loose_object(add_loose_objects_to_set,
 +					    &iter, 0);
  
  	save_commit_buffer = 0;
  
  	for (ref = *refs; ref; ref = ref->next) {
  		struct object *o;
 +		unsigned int flags = OBJECT_INFO_QUICK;
  
 -		if (!has_object_file_with_flags(&ref->old_oid,
 -						OBJECT_INFO_QUICK))
 -			continue;
 +		if (use_oidset &&
 +		    !oidset_contains(&loose_oid_set, &ref->old_oid)) {
 +			/*
 +			 * I know this does not exist in the loose form,
 +			 * so check if it exists in a non-loose form.
 +			 */
 +			flags |= OBJECT_INFO_IGNORE_LOOSE;
 +		}
  
 +		if (!has_object_file_with_flags(&ref->old_oid, flags))
 +			continue;
  		o = parse_object(&ref->old_oid);
  		if (!o)
  			continue;
@@@ -782,33 -735,29 +782,33 @@@
  		}
  	}
  
 -	if (!args->deepen) {
 -		for_each_ref(mark_complete_oid, NULL);
 -		for_each_cached_alternate(mark_alternate_complete);
 -		commit_list_sort_by_date(&complete);
 -		if (cutoff)
 -			mark_recent_complete_commits(args, cutoff);
 -	}
 +	oidset_clear(&loose_oid_set);
  
 -	/*
 -	 * Mark all complete remote refs as common refs.
 -	 * Don't mark them common yet; the server has to be told so first.
 -	 */
 -	for (ref = *refs; ref; ref = ref->next) {
 -		struct object *o = deref_tag(lookup_object(ref->old_oid.hash),
 -					     NULL, 0);
 +	if (!args->no_dependents) {
 +		if (!args->deepen) {
 +			for_each_ref(mark_complete_oid, NULL);
 +			for_each_cached_alternate(mark_alternate_complete);
 +			commit_list_sort_by_date(&complete);
 +			if (cutoff)
 +				mark_recent_complete_commits(args, cutoff);
 +		}
  
 -		if (!o || o->type != OBJ_COMMIT || !(o->flags & COMPLETE))
 -			continue;
 +		/*
 +		 * Mark all complete remote refs as common refs.
 +		 * Don't mark them common yet; the server has to be told so first.
 +		 */
 +		for (ref = *refs; ref; ref = ref->next) {
 +			struct object *o = deref_tag(lookup_object(ref->old_oid.hash),
 +						     NULL, 0);
 +
 +			if (!o || o->type != OBJ_COMMIT || !(o->flags & COMPLETE))
 +				continue;
  
 -		if (!(o->flags & SEEN)) {
 -			rev_list_push((struct commit *)o, COMMON_REF | SEEN);
 +			if (!(o->flags & SEEN)) {
 +				rev_list_push((struct commit *)o, COMMON_REF | SEEN);
  
 -			mark_common((struct commit *)o, 1, 1);
 +				mark_common((struct commit *)o, 1, 1);
 +			}
  		}
  	}
  
@@@ -828,9 -777,6 +828,9 @@@
  		print_verbose(args, _("already have %s (%s)"), oid_to_hex(remote),
  			      ref->name);
  	}
 +
 +	save_commit_buffer = old_save_commit_buffer;
 +
  	return retval;
  }
  
@@@ -887,7 -833,7 +887,7 @@@ static int get_pack(struct fetch_pack_a
  		argv_array_push(&cmd.args, alternate_shallow_file);
  	}
  
 -	if (do_keep) {
 +	if (do_keep || args->from_promisor) {
  		if (pack_lockfile)
  			cmd.out = -1;
  		cmd_name = "index-pack";
@@@ -897,7 -843,7 +897,7 @@@
  			argv_array_push(&cmd.args, "-v");
  		if (args->use_thin_pack)
  			argv_array_push(&cmd.args, "--fix-thin");
 -		if (args->lock_pack || unpack_limit) {
 +		if (do_keep && (args->lock_pack || unpack_limit)) {
  			char hostname[HOST_NAME_MAX + 1];
  			if (xgethostname(hostname, sizeof(hostname)))
  				xsnprintf(hostname, sizeof(hostname), "localhost");
@@@ -907,8 -853,6 +907,8 @@@
  		}
  		if (args->check_self_contained_and_connected)
  			argv_array_push(&cmd.args, "--check-self-contained-and-connected");
 +		if (args->from_promisor)
 +			argv_array_push(&cmd.args, "--promisor");
  	}
  	else {
  		cmd_name = "unpack-objects";
@@@ -926,17 -870,8 +926,17 @@@
  	    ? fetch_fsck_objects
  	    : transfer_fsck_objects >= 0
  	    ? transfer_fsck_objects
 -	    : 0)
 -		argv_array_push(&cmd.args, "--strict");
 +	    : 0) {
 +		if (args->from_promisor)
 +			/*
 +			 * We cannot use --strict in index-pack because it
 +			 * checks both broken objects and links, but we only
 +			 * want to check for broken objects.
 +			 */
 +			argv_array_push(&cmd.args, "--fsck-objects");
 +		else
 +			argv_array_push(&cmd.args, "--strict");
 +	}
  
  	cmd.in = demux.out;
  	cmd.git_cmd = 1;
@@@ -1029,13 -964,6 +1029,13 @@@ static struct ref *do_fetch_pack(struc
  	else
  		prefer_ofs_delta = 0;
  
 +	if (server_supports("filter")) {
 +		server_supports_filtering = 1;
 +		print_verbose(args, _("Server supports filter"));
 +	} else if (args->filter_options.choice) {
 +		warning("filtering not recognized by server, ignoring");
 +	}
 +
  	if ((agent_feature = server_feature_value("agent", &agent_len))) {
  		agent_supported = 1;
  		if (agent_len)
@@@ -1080,6 -1008,328 +1080,328 @@@
  	return ref;
  }
  
+ static void add_shallow_requests(struct strbuf *req_buf,
+ 				 const struct fetch_pack_args *args)
+ {
+ 	if (is_repository_shallow())
+ 		write_shallow_commits(req_buf, 1, NULL);
+ 	if (args->depth > 0)
+ 		packet_buf_write(req_buf, "deepen %d", args->depth);
+ 	if (args->deepen_since) {
+ 		timestamp_t max_age = approxidate(args->deepen_since);
+ 		packet_buf_write(req_buf, "deepen-since %"PRItime, max_age);
+ 	}
+ 	if (args->deepen_not) {
+ 		int i;
+ 		for (i = 0; i < args->deepen_not->nr; i++) {
+ 			struct string_list_item *s = args->deepen_not->items + i;
+ 			packet_buf_write(req_buf, "deepen-not %s", s->string);
+ 		}
+ 	}
+ }
+ 
+ static void add_wants(const struct ref *wants, struct strbuf *req_buf)
+ {
+ 	for ( ; wants ; wants = wants->next) {
+ 		const struct object_id *remote = &wants->old_oid;
+ 		const char *remote_hex;
+ 		struct object *o;
+ 
+ 		/*
+ 		 * If that object is complete (i.e. it is an ancestor of a
+ 		 * local ref), we tell them we have it but do not have to
+ 		 * tell them about its ancestors, which they already know
+ 		 * about.
+ 		 *
+ 		 * We use lookup_object here because we are only
+ 		 * interested in the case we *know* the object is
+ 		 * reachable and we have already scanned it.
+ 		 */
+ 		if (((o = lookup_object(remote->hash)) != NULL) &&
+ 		    (o->flags & COMPLETE)) {
+ 			continue;
+ 		}
+ 
+ 		remote_hex = oid_to_hex(remote);
+ 		packet_buf_write(req_buf, "want %s\n", remote_hex);
+ 	}
+ }
+ 
+ static void add_common(struct strbuf *req_buf, struct oidset *common)
+ {
+ 	struct oidset_iter iter;
+ 	const struct object_id *oid;
+ 	oidset_iter_init(common, &iter);
+ 
+ 	while ((oid = oidset_iter_next(&iter))) {
+ 		packet_buf_write(req_buf, "have %s\n", oid_to_hex(oid));
+ 	}
+ }
+ 
+ static int add_haves(struct strbuf *req_buf, int *haves_to_send, int *in_vain)
+ {
+ 	int ret = 0;
+ 	int haves_added = 0;
+ 	const struct object_id *oid;
+ 
+ 	while ((oid = get_rev())) {
+ 		packet_buf_write(req_buf, "have %s\n", oid_to_hex(oid));
+ 		if (++haves_added >= *haves_to_send)
+ 			break;
+ 	}
+ 
+ 	*in_vain += haves_added;
+ 	if (!haves_added || *in_vain >= MAX_IN_VAIN) {
+ 		/* Send Done */
+ 		packet_buf_write(req_buf, "done\n");
+ 		ret = 1;
+ 	}
+ 
+ 	/* Increase haves to send on next round */
+ 	*haves_to_send = next_flush(1, *haves_to_send);
+ 
+ 	return ret;
+ }
+ 
+ static int send_fetch_request(int fd_out, const struct fetch_pack_args *args,
+ 			      const struct ref *wants, struct oidset *common,
+ 			      int *haves_to_send, int *in_vain)
+ {
+ 	int ret = 0;
+ 	struct strbuf req_buf = STRBUF_INIT;
+ 
+ 	if (server_supports_v2("fetch", 1))
+ 		packet_buf_write(&req_buf, "command=fetch");
+ 	if (server_supports_v2("agent", 0))
+ 		packet_buf_write(&req_buf, "agent=%s", git_user_agent_sanitized());
+ 
+ 	packet_buf_delim(&req_buf);
+ 	if (args->use_thin_pack)
+ 		packet_buf_write(&req_buf, "thin-pack");
+ 	if (args->no_progress)
+ 		packet_buf_write(&req_buf, "no-progress");
+ 	if (args->include_tag)
+ 		packet_buf_write(&req_buf, "include-tag");
+ 	if (prefer_ofs_delta)
+ 		packet_buf_write(&req_buf, "ofs-delta");
+ 
+ 	/* Add shallow-info and deepen request */
+ 	if (server_supports_feature("fetch", "shallow", 0))
+ 		add_shallow_requests(&req_buf, args);
+ 	else if (is_repository_shallow() || args->deepen)
+ 		die(_("Server does not support shallow requests"));
+ 
+ 	/* add wants */
+ 	add_wants(wants, &req_buf);
+ 
+ 	/* Add all of the common commits we've found in previous rounds */
+ 	add_common(&req_buf, common);
+ 
+ 	/* Add initial haves */
+ 	ret = add_haves(&req_buf, haves_to_send, in_vain);
+ 
+ 	/* Send request */
+ 	packet_buf_flush(&req_buf);
+ 	write_or_die(fd_out, req_buf.buf, req_buf.len);
+ 
+ 	strbuf_release(&req_buf);
+ 	return ret;
+ }
+ 
+ /*
+  * Processes a section header in a server's response and checks if it matches
+  * `section`.  If the value of `peek` is 1, the header line will be peeked (and
+  * not consumed); if 0, the line will be consumed and the function will die if
+  * the section header doesn't match what was expected.
+  */
+ static int process_section_header(struct packet_reader *reader,
+ 				  const char *section, int peek)
+ {
+ 	int ret;
+ 
+ 	if (packet_reader_peek(reader) != PACKET_READ_NORMAL)
+ 		die("error reading section header '%s'", section);
+ 
+ 	ret = !strcmp(reader->line, section);
+ 
+ 	if (!peek) {
+ 		if (!ret)
+ 			die("expected '%s', received '%s'",
+ 			    section, reader->line);
+ 		packet_reader_read(reader);
+ 	}
+ 
+ 	return ret;
+ }
+ 
+ static int process_acks(struct packet_reader *reader, struct oidset *common)
+ {
+ 	/* received */
+ 	int received_ready = 0;
+ 	int received_ack = 0;
+ 
+ 	process_section_header(reader, "acknowledgments", 0);
+ 	while (packet_reader_read(reader) == PACKET_READ_NORMAL) {
+ 		const char *arg;
+ 
+ 		if (!strcmp(reader->line, "NAK"))
+ 			continue;
+ 
+ 		if (skip_prefix(reader->line, "ACK ", &arg)) {
+ 			struct object_id oid;
+ 			if (!get_oid_hex(arg, &oid)) {
+ 				struct commit *commit;
+ 				oidset_insert(common, &oid);
+ 				commit = lookup_commit(&oid);
+ 				mark_common(commit, 0, 1);
+ 			}
+ 			continue;
+ 		}
+ 
+ 		if (!strcmp(reader->line, "ready")) {
+ 			clear_prio_queue(&rev_list);
+ 			received_ready = 1;
+ 			continue;
+ 		}
+ 
+ 		die("unexpected acknowledgment line: '%s'", reader->line);
+ 	}
+ 
+ 	if (reader->status != PACKET_READ_FLUSH &&
+ 	    reader->status != PACKET_READ_DELIM)
+ 		die("error processing acks: %d", reader->status);
+ 
+ 	/* return 0 if no common, 1 if there are common, or 2 if ready */
+ 	return received_ready ? 2 : (received_ack ? 1 : 0);
+ }
+ 
+ static void receive_shallow_info(struct fetch_pack_args *args,
+ 				 struct packet_reader *reader)
+ {
+ 	process_section_header(reader, "shallow-info", 0);
+ 	while (packet_reader_read(reader) == PACKET_READ_NORMAL) {
+ 		const char *arg;
+ 		struct object_id oid;
+ 
+ 		if (skip_prefix(reader->line, "shallow ", &arg)) {
+ 			if (get_oid_hex(arg, &oid))
+ 				die(_("invalid shallow line: %s"), reader->line);
+ 			register_shallow(&oid);
+ 			continue;
+ 		}
+ 		if (skip_prefix(reader->line, "unshallow ", &arg)) {
+ 			if (get_oid_hex(arg, &oid))
+ 				die(_("invalid unshallow line: %s"), reader->line);
+ 			if (!lookup_object(oid.hash))
+ 				die(_("object not found: %s"), reader->line);
+ 			/* make sure that it is parsed as shallow */
+ 			if (!parse_object(&oid))
+ 				die(_("error in object: %s"), reader->line);
+ 			if (unregister_shallow(&oid))
+ 				die(_("no shallow found: %s"), reader->line);
+ 			continue;
+ 		}
+ 		die(_("expected shallow/unshallow, got %s"), reader->line);
+ 	}
+ 
+ 	if (reader->status != PACKET_READ_FLUSH &&
+ 	    reader->status != PACKET_READ_DELIM)
+ 		die("error processing shallow info: %d", reader->status);
+ 
+ 	setup_alternate_shallow(&shallow_lock, &alternate_shallow_file, NULL);
+ 	args->deepen = 1;
+ }
+ 
+ enum fetch_state {
+ 	FETCH_CHECK_LOCAL = 0,
+ 	FETCH_SEND_REQUEST,
+ 	FETCH_PROCESS_ACKS,
+ 	FETCH_GET_PACK,
+ 	FETCH_DONE,
+ };
+ 
+ static struct ref *do_fetch_pack_v2(struct fetch_pack_args *args,
+ 				    int fd[2],
+ 				    const struct ref *orig_ref,
+ 				    struct ref **sought, int nr_sought,
+ 				    char **pack_lockfile)
+ {
+ 	struct ref *ref = copy_ref_list(orig_ref);
+ 	enum fetch_state state = FETCH_CHECK_LOCAL;
+ 	struct oidset common = OIDSET_INIT;
+ 	struct packet_reader reader;
+ 	int in_vain = 0;
+ 	int haves_to_send = INITIAL_FLUSH;
+ 	packet_reader_init(&reader, fd[0], NULL, 0,
+ 			   PACKET_READ_CHOMP_NEWLINE);
+ 
+ 	while (state != FETCH_DONE) {
+ 		switch (state) {
+ 		case FETCH_CHECK_LOCAL:
+ 			sort_ref_list(&ref, ref_compare_name);
+ 			QSORT(sought, nr_sought, cmp_ref_by_name);
+ 
+ 			/* v2 supports these by default */
+ 			allow_unadvertised_object_request |= ALLOW_REACHABLE_SHA1;
+ 			use_sideband = 2;
+ 			if (args->depth > 0 || args->deepen_since || args->deepen_not)
+ 				args->deepen = 1;
+ 
+ 			if (marked)
+ 				for_each_ref(clear_marks, NULL);
+ 			marked = 1;
+ 
+ 			for_each_ref(rev_list_insert_ref_oid, NULL);
+ 			for_each_cached_alternate(insert_one_alternate_object);
+ 
+ 			/* Filter 'ref' by 'sought' and those that aren't local */
+ 			if (everything_local(args, &ref, sought, nr_sought))
+ 				state = FETCH_DONE;
+ 			else
+ 				state = FETCH_SEND_REQUEST;
+ 			break;
+ 		case FETCH_SEND_REQUEST:
+ 			if (send_fetch_request(fd[1], args, ref, &common,
+ 					       &haves_to_send, &in_vain))
+ 				state = FETCH_GET_PACK;
+ 			else
+ 				state = FETCH_PROCESS_ACKS;
+ 			break;
+ 		case FETCH_PROCESS_ACKS:
+ 			/* Process ACKs/NAKs */
+ 			switch (process_acks(&reader, &common)) {
+ 			case 2:
+ 				state = FETCH_GET_PACK;
+ 				break;
+ 			case 1:
+ 				in_vain = 0;
+ 				/* fallthrough */
+ 			default:
+ 				state = FETCH_SEND_REQUEST;
+ 				break;
+ 			}
+ 			break;
+ 		case FETCH_GET_PACK:
+ 			/* Check for shallow-info section */
+ 			if (process_section_header(&reader, "shallow-info", 1))
+ 				receive_shallow_info(args, &reader);
+ 
+ 			/* get the pack */
+ 			process_section_header(&reader, "packfile", 0);
+ 			if (get_pack(args, fd, pack_lockfile))
+ 				die(_("git fetch-pack: fetch failed."));
+ 
+ 			state = FETCH_DONE;
+ 			break;
+ 		case FETCH_DONE:
+ 			continue;
+ 		}
+ 	}
+ 
+ 	oidset_clear(&common);
+ 	return ref;
+ }
+ 
  static void fetch_pack_config(void)
  {
  	git_config_get_int("fetch.unpacklimit", &fetch_unpack_limit);
@@@ -1225,7 -1475,8 +1547,8 @@@ struct ref *fetch_pack(struct fetch_pac
  		       const char *dest,
  		       struct ref **sought, int nr_sought,
  		       struct oid_array *shallow,
- 		       char **pack_lockfile)
+ 		       char **pack_lockfile,
+ 		       enum protocol_version version)
  {
  	struct ref *ref_cpy;
  	struct shallow_info si;
@@@ -1239,9 -1490,13 +1562,13 @@@
  		die(_("no matching remote head"));
  	}
  	prepare_shallow_info(&si, shallow);
- 	ref_cpy = do_fetch_pack(args, fd, ref, sought, nr_sought,
- 				&si, pack_lockfile);
+ 	if (version == protocol_v2)
+ 		ref_cpy = do_fetch_pack_v2(args, fd, ref, sought, nr_sought,
+ 					   pack_lockfile);
+ 	else
+ 		ref_cpy = do_fetch_pack(args, fd, ref, sought, nr_sought,
+ 					&si, pack_lockfile);
 -	reprepare_packed_git();
 +	reprepare_packed_git(the_repository);
  	update_shallow(args, sought, nr_sought, &si);
  	clear_shallow_info(&si);
  	return ref_cpy;
diff --combined fetch-pack.h
index 3e224a1822,7afca73056..6afa08b48b
--- a/fetch-pack.h
+++ b/fetch-pack.h
@@@ -3,7 -3,7 +3,8 @@@
  
  #include "string-list.h"
  #include "run-command.h"
+ #include "protocol.h"
 +#include "list-objects-filter-options.h"
  
  struct oid_array;
  
@@@ -13,7 -13,6 +14,7 @@@ struct fetch_pack_args 
  	int depth;
  	const char *deepen_since;
  	const struct string_list *deepen_not;
 +	struct list_objects_filter_options filter_options;
  	unsigned deepen_relative:1;
  	unsigned quiet:1;
  	unsigned keep_pack:1;
@@@ -31,14 -30,6 +32,14 @@@
  	unsigned cloning:1;
  	unsigned update_shallow:1;
  	unsigned deepen:1;
 +	unsigned from_promisor:1;
 +
 +	/*
 +	 * If 1, fetch_pack() will also not modify any object flags.
 +	 * This allows fetch_pack() to safely be called by any function,
 +	 * regardless of which object flags it uses (if any).
 +	 */
 +	unsigned no_dependents:1;
  };
  
  /*
@@@ -53,7 -44,8 +54,8 @@@ struct ref *fetch_pack(struct fetch_pac
  		       struct ref **sought,
  		       int nr_sought,
  		       struct oid_array *shallow,
- 		       char **pack_lockfile);
+ 		       char **pack_lockfile,
+ 		       enum protocol_version version);
  
  /*
   * Print an appropriate error message for each sought ref that wasn't
diff --combined git.c
index 3a89893712,f85d682b62..b73a550edd
--- a/git.c
+++ b/git.c
@@@ -4,30 -4,12 +4,30 @@@
  #include "help.h"
  #include "run-command.h"
  
 +#define RUN_SETUP		(1<<0)
 +#define RUN_SETUP_GENTLY	(1<<1)
 +#define USE_PAGER		(1<<2)
 +/*
 + * require working tree to be present -- anything uses this needs
 + * RUN_SETUP for reading from the configuration file.
 + */
 +#define NEED_WORK_TREE		(1<<3)
 +#define SUPPORT_SUPER_PREFIX	(1<<4)
 +#define DELAY_PAGER_CONFIG	(1<<5)
 +#define NO_PARSEOPT		(1<<6) /* parse-options is not used */
 +
 +struct cmd_struct {
 +	const char *cmd;
 +	int (*fn)(int, const char **, const char *);
 +	unsigned int option;
 +};
 +
  const char git_usage_string[] =
 -	"git [--version] [--help] [-C <path>] [-c name=value]\n"
 -	"           [--exec-path[=<path>]] [--html-path] [--man-path] [--info-path]\n"
 -	"           [-p | --paginate | --no-pager] [--no-replace-objects] [--bare]\n"
 -	"           [--git-dir=<path>] [--work-tree=<path>] [--namespace=<name>]\n"
 -	"           <command> [<args>]";
 +	N_("git [--version] [--help] [-C <path>] [-c <name>=<value>]\n"
 +	   "           [--exec-path[=<path>]] [--html-path] [--man-path] [--info-path]\n"
 +	   "           [-p | --paginate | --no-pager] [--no-replace-objects] [--bare]\n"
 +	   "           [--git-dir=<path>] [--work-tree=<path>] [--namespace=<name>]\n"
 +	   "           <command> [<args>]");
  
  const char git_more_info_string[] =
  	N_("'git help -a' and 'git help -g' list available subcommands and some\n"
@@@ -36,7 -18,7 +36,7 @@@
  
  static int use_pager = -1;
  
 -static void list_builtins(void);
 +static void list_builtins(unsigned int exclude_option, char sep);
  
  static void commit_pager_choice(void) {
  	switch (use_pager) {
@@@ -110,7 -92,7 +110,7 @@@ static int handle_options(const char **
  				*envchanged = 1;
  		} else if (!strcmp(cmd, "--git-dir")) {
  			if (*argc < 2) {
 -				fprintf(stderr, "No directory given for --git-dir.\n" );
 +				fprintf(stderr, _("no directory given for --git-dir\n" ));
  				usage(git_usage_string);
  			}
  			setenv(GIT_DIR_ENVIRONMENT, (*argv)[1], 1);
@@@ -124,7 -106,7 +124,7 @@@
  				*envchanged = 1;
  		} else if (!strcmp(cmd, "--namespace")) {
  			if (*argc < 2) {
 -				fprintf(stderr, "No namespace given for --namespace.\n" );
 +				fprintf(stderr, _("no namespace given for --namespace\n" ));
  				usage(git_usage_string);
  			}
  			setenv(GIT_NAMESPACE_ENVIRONMENT, (*argv)[1], 1);
@@@ -138,7 -120,7 +138,7 @@@
  				*envchanged = 1;
  		} else if (!strcmp(cmd, "--work-tree")) {
  			if (*argc < 2) {
 -				fprintf(stderr, "No directory given for --work-tree.\n" );
 +				fprintf(stderr, _("no directory given for --work-tree\n" ));
  				usage(git_usage_string);
  			}
  			setenv(GIT_WORK_TREE_ENVIRONMENT, (*argv)[1], 1);
@@@ -152,7 -134,7 +152,7 @@@
  				*envchanged = 1;
  		} else if (!strcmp(cmd, "--super-prefix")) {
  			if (*argc < 2) {
 -				fprintf(stderr, "No prefix given for --super-prefix.\n" );
 +				fprintf(stderr, _("no prefix given for --super-prefix\n" ));
  				usage(git_usage_string);
  			}
  			setenv(GIT_SUPER_PREFIX_ENVIRONMENT, (*argv)[1], 1);
@@@ -174,7 -156,7 +174,7 @@@
  				*envchanged = 1;
  		} else if (!strcmp(cmd, "-c")) {
  			if (*argc < 2) {
 -				fprintf(stderr, "-c expects a configuration string\n" );
 +				fprintf(stderr, _("-c expects a configuration string\n" ));
  				usage(git_usage_string);
  			}
  			git_config_push_parameter((*argv)[1]);
@@@ -212,25 -194,22 +212,25 @@@
  				*envchanged = 1;
  		} else if (!strcmp(cmd, "-C")) {
  			if (*argc < 2) {
 -				fprintf(stderr, "No directory given for -C.\n" );
 +				fprintf(stderr, _("no directory given for -C\n" ));
  				usage(git_usage_string);
  			}
  			if ((*argv)[1][0]) {
  				if (chdir((*argv)[1]))
 -					die_errno("Cannot change to '%s'", (*argv)[1]);
 +					die_errno("cannot change to '%s'", (*argv)[1]);
  				if (envchanged)
  					*envchanged = 1;
  			}
  			(*argv)++;
  			(*argc)--;
  		} else if (!strcmp(cmd, "--list-builtins")) {
 -			list_builtins();
 +			list_builtins(0, '\n');
 +			exit(0);
 +		} else if (!strcmp(cmd, "--list-parseopt-builtins")) {
 +			list_builtins(NO_PARSEOPT, ' ');
  			exit(0);
  		} else {
 -			fprintf(stderr, "Unknown option: %s\n", cmd);
 +			fprintf(stderr, _("unknown option: %s\n"), cmd);
  			usage(git_usage_string);
  		}
  
@@@ -268,7 -247,7 +268,7 @@@ static int handle_alias(int *argcp, con
  			if (ret >= 0)   /* normal exit */
  				exit(ret);
  
 -			die_errno("While expanding alias '%s': '%s'",
 +			die_errno("while expanding alias '%s': '%s'",
  			    alias_command, alias_string + 1);
  		}
  		count = split_cmdline(alias_string, &new_argv);
@@@ -277,8 -256,8 +277,8 @@@
  			    split_cmdline_strerror(count));
  		option_count = handle_options(&new_argv, &count, &envchanged);
  		if (envchanged)
 -			die("alias '%s' changes environment variables\n"
 -				 "You can use '!git' in the alias to do this.",
 +			die("alias '%s' changes environment variables.\n"
 +				 "You can use '!git' in the alias to do this",
  				 alias_command);
  		memmove(new_argv - option_count, new_argv,
  				count * sizeof(char *));
@@@ -309,6 -288,23 +309,6 @@@
  	return ret;
  }
  
 -#define RUN_SETUP		(1<<0)
 -#define RUN_SETUP_GENTLY	(1<<1)
 -#define USE_PAGER		(1<<2)
 -/*
 - * require working tree to be present -- anything uses this needs
 - * RUN_SETUP for reading from the configuration file.
 - */
 -#define NEED_WORK_TREE		(1<<3)
 -#define SUPPORT_SUPER_PREFIX	(1<<4)
 -#define DELAY_PAGER_CONFIG	(1<<5)
 -
 -struct cmd_struct {
 -	const char *cmd;
 -	int (*fn)(int, const char **, const char *);
 -	int option;
 -};
 -
  static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
  {
  	int status, help;
@@@ -371,18 -367,18 +371,18 @@@
  static struct cmd_struct commands[] = {
  	{ "add", cmd_add, RUN_SETUP | NEED_WORK_TREE },
  	{ "am", cmd_am, RUN_SETUP | NEED_WORK_TREE },
 -	{ "annotate", cmd_annotate, RUN_SETUP },
 +	{ "annotate", cmd_annotate, RUN_SETUP | NO_PARSEOPT },
  	{ "apply", cmd_apply, RUN_SETUP_GENTLY },
  	{ "archive", cmd_archive, RUN_SETUP_GENTLY },
  	{ "bisect--helper", cmd_bisect__helper, RUN_SETUP },
  	{ "blame", cmd_blame, RUN_SETUP },
  	{ "branch", cmd_branch, RUN_SETUP | DELAY_PAGER_CONFIG },
 -	{ "bundle", cmd_bundle, RUN_SETUP_GENTLY },
 +	{ "bundle", cmd_bundle, RUN_SETUP_GENTLY | NO_PARSEOPT },
  	{ "cat-file", cmd_cat_file, RUN_SETUP },
  	{ "check-attr", cmd_check_attr, RUN_SETUP },
  	{ "check-ignore", cmd_check_ignore, RUN_SETUP | NEED_WORK_TREE },
  	{ "check-mailmap", cmd_check_mailmap, RUN_SETUP },
 -	{ "check-ref-format", cmd_check_ref_format },
 +	{ "check-ref-format", cmd_check_ref_format, NO_PARSEOPT  },
  	{ "checkout", cmd_checkout, RUN_SETUP | NEED_WORK_TREE },
  	{ "checkout-index", cmd_checkout_index,
  		RUN_SETUP | NEED_WORK_TREE},
@@@ -392,30 -388,30 +392,30 @@@
  	{ "clone", cmd_clone },
  	{ "column", cmd_column, RUN_SETUP_GENTLY },
  	{ "commit", cmd_commit, RUN_SETUP | NEED_WORK_TREE },
 -	{ "commit-tree", cmd_commit_tree, RUN_SETUP },
 -	{ "config", cmd_config, RUN_SETUP_GENTLY },
 +	{ "commit-tree", cmd_commit_tree, RUN_SETUP | NO_PARSEOPT },
 +	{ "config", cmd_config, RUN_SETUP_GENTLY | DELAY_PAGER_CONFIG },
  	{ "count-objects", cmd_count_objects, RUN_SETUP },
 -	{ "credential", cmd_credential, RUN_SETUP_GENTLY },
 +	{ "credential", cmd_credential, RUN_SETUP_GENTLY | NO_PARSEOPT },
  	{ "describe", cmd_describe, RUN_SETUP },
 -	{ "diff", cmd_diff },
 -	{ "diff-files", cmd_diff_files, RUN_SETUP | NEED_WORK_TREE },
 -	{ "diff-index", cmd_diff_index, RUN_SETUP },
 -	{ "diff-tree", cmd_diff_tree, RUN_SETUP },
 +	{ "diff", cmd_diff, NO_PARSEOPT },
 +	{ "diff-files", cmd_diff_files, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
 +	{ "diff-index", cmd_diff_index, RUN_SETUP | NO_PARSEOPT },
 +	{ "diff-tree", cmd_diff_tree, RUN_SETUP | NO_PARSEOPT },
  	{ "difftool", cmd_difftool, RUN_SETUP | NEED_WORK_TREE },
  	{ "fast-export", cmd_fast_export, RUN_SETUP },
  	{ "fetch", cmd_fetch, RUN_SETUP },
 -	{ "fetch-pack", cmd_fetch_pack, RUN_SETUP },
 +	{ "fetch-pack", cmd_fetch_pack, RUN_SETUP | NO_PARSEOPT },
  	{ "fmt-merge-msg", cmd_fmt_merge_msg, RUN_SETUP },
  	{ "for-each-ref", cmd_for_each_ref, RUN_SETUP },
  	{ "format-patch", cmd_format_patch, RUN_SETUP },
  	{ "fsck", cmd_fsck, RUN_SETUP },
  	{ "fsck-objects", cmd_fsck, RUN_SETUP },
  	{ "gc", cmd_gc, RUN_SETUP },
 -	{ "get-tar-commit-id", cmd_get_tar_commit_id },
 +	{ "get-tar-commit-id", cmd_get_tar_commit_id, NO_PARSEOPT },
  	{ "grep", cmd_grep, RUN_SETUP_GENTLY },
  	{ "hash-object", cmd_hash_object },
  	{ "help", cmd_help },
 -	{ "index-pack", cmd_index_pack, RUN_SETUP_GENTLY },
 +	{ "index-pack", cmd_index_pack, RUN_SETUP_GENTLY | NO_PARSEOPT },
  	{ "init", cmd_init_db },
  	{ "init-db", cmd_init_db },
  	{ "interpret-trailers", cmd_interpret_trailers, RUN_SETUP_GENTLY },
@@@ -423,27 -419,27 +423,27 @@@
  	{ "ls-files", cmd_ls_files, RUN_SETUP },
  	{ "ls-remote", cmd_ls_remote, RUN_SETUP_GENTLY },
  	{ "ls-tree", cmd_ls_tree, RUN_SETUP },
 -	{ "mailinfo", cmd_mailinfo, RUN_SETUP_GENTLY },
 -	{ "mailsplit", cmd_mailsplit },
 +	{ "mailinfo", cmd_mailinfo, RUN_SETUP_GENTLY | NO_PARSEOPT },
 +	{ "mailsplit", cmd_mailsplit, NO_PARSEOPT },
  	{ "merge", cmd_merge, RUN_SETUP | NEED_WORK_TREE },
  	{ "merge-base", cmd_merge_base, RUN_SETUP },
  	{ "merge-file", cmd_merge_file, RUN_SETUP_GENTLY },
 -	{ "merge-index", cmd_merge_index, RUN_SETUP },
 -	{ "merge-ours", cmd_merge_ours, RUN_SETUP },
 -	{ "merge-recursive", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
 -	{ "merge-recursive-ours", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
 -	{ "merge-recursive-theirs", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
 -	{ "merge-subtree", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
 -	{ "merge-tree", cmd_merge_tree, RUN_SETUP },
 -	{ "mktag", cmd_mktag, RUN_SETUP },
 +	{ "merge-index", cmd_merge_index, RUN_SETUP | NO_PARSEOPT },
 +	{ "merge-ours", cmd_merge_ours, RUN_SETUP | NO_PARSEOPT },
 +	{ "merge-recursive", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
 +	{ "merge-recursive-ours", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
 +	{ "merge-recursive-theirs", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
 +	{ "merge-subtree", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
 +	{ "merge-tree", cmd_merge_tree, RUN_SETUP | NO_PARSEOPT },
 +	{ "mktag", cmd_mktag, RUN_SETUP | NO_PARSEOPT },
  	{ "mktree", cmd_mktree, RUN_SETUP },
  	{ "mv", cmd_mv, RUN_SETUP | NEED_WORK_TREE },
  	{ "name-rev", cmd_name_rev, RUN_SETUP },
  	{ "notes", cmd_notes, RUN_SETUP },
  	{ "pack-objects", cmd_pack_objects, RUN_SETUP },
 -	{ "pack-redundant", cmd_pack_redundant, RUN_SETUP },
 +	{ "pack-redundant", cmd_pack_redundant, RUN_SETUP | NO_PARSEOPT },
  	{ "pack-refs", cmd_pack_refs, RUN_SETUP },
 -	{ "patch-id", cmd_patch_id, RUN_SETUP_GENTLY },
 +	{ "patch-id", cmd_patch_id, RUN_SETUP_GENTLY | NO_PARSEOPT },
  	{ "pickaxe", cmd_blame, RUN_SETUP },
  	{ "prune", cmd_prune, RUN_SETUP },
  	{ "prune-packed", cmd_prune_packed, RUN_SETUP },
@@@ -454,17 -450,18 +454,18 @@@
  	{ "receive-pack", cmd_receive_pack },
  	{ "reflog", cmd_reflog, RUN_SETUP },
  	{ "remote", cmd_remote, RUN_SETUP },
 -	{ "remote-ext", cmd_remote_ext },
 -	{ "remote-fd", cmd_remote_fd },
 +	{ "remote-ext", cmd_remote_ext, NO_PARSEOPT },
 +	{ "remote-fd", cmd_remote_fd, NO_PARSEOPT },
  	{ "repack", cmd_repack, RUN_SETUP },
  	{ "replace", cmd_replace, RUN_SETUP },
  	{ "rerere", cmd_rerere, RUN_SETUP },
  	{ "reset", cmd_reset, RUN_SETUP },
 -	{ "rev-list", cmd_rev_list, RUN_SETUP },
 -	{ "rev-parse", cmd_rev_parse },
 +	{ "rev-list", cmd_rev_list, RUN_SETUP | NO_PARSEOPT },
 +	{ "rev-parse", cmd_rev_parse, NO_PARSEOPT },
  	{ "revert", cmd_revert, RUN_SETUP | NEED_WORK_TREE },
  	{ "rm", cmd_rm, RUN_SETUP },
  	{ "send-pack", cmd_send_pack, RUN_SETUP },
+ 	{ "serve", cmd_serve, RUN_SETUP },
  	{ "shortlog", cmd_shortlog, RUN_SETUP_GENTLY | USE_PAGER },
  	{ "show", cmd_show, RUN_SETUP },
  	{ "show-branch", cmd_show_branch, RUN_SETUP },
@@@ -472,23 -469,24 +473,24 @@@
  	{ "stage", cmd_add, RUN_SETUP | NEED_WORK_TREE },
  	{ "status", cmd_status, RUN_SETUP | NEED_WORK_TREE },
  	{ "stripspace", cmd_stripspace },
 -	{ "submodule--helper", cmd_submodule__helper, RUN_SETUP | SUPPORT_SUPER_PREFIX},
 +	{ "submodule--helper", cmd_submodule__helper, RUN_SETUP | SUPPORT_SUPER_PREFIX | NO_PARSEOPT },
  	{ "symbolic-ref", cmd_symbolic_ref, RUN_SETUP },
  	{ "tag", cmd_tag, RUN_SETUP | DELAY_PAGER_CONFIG },
 -	{ "unpack-file", cmd_unpack_file, RUN_SETUP },
 -	{ "unpack-objects", cmd_unpack_objects, RUN_SETUP },
 +	{ "unpack-file", cmd_unpack_file, RUN_SETUP | NO_PARSEOPT },
 +	{ "unpack-objects", cmd_unpack_objects, RUN_SETUP | NO_PARSEOPT },
  	{ "update-index", cmd_update_index, RUN_SETUP },
  	{ "update-ref", cmd_update_ref, RUN_SETUP },
  	{ "update-server-info", cmd_update_server_info, RUN_SETUP },
 -	{ "upload-archive", cmd_upload_archive },
 -	{ "upload-archive--writer", cmd_upload_archive_writer },
 +	{ "upload-archive", cmd_upload_archive, NO_PARSEOPT },
 +	{ "upload-archive--writer", cmd_upload_archive_writer, NO_PARSEOPT },
+ 	{ "upload-pack", cmd_upload_pack },
 -	{ "var", cmd_var, RUN_SETUP_GENTLY },
 +	{ "var", cmd_var, RUN_SETUP_GENTLY | NO_PARSEOPT },
  	{ "verify-commit", cmd_verify_commit, RUN_SETUP },
  	{ "verify-pack", cmd_verify_pack },
  	{ "verify-tag", cmd_verify_tag, RUN_SETUP },
  	{ "version", cmd_version },
  	{ "whatchanged", cmd_whatchanged, RUN_SETUP },
 -	{ "worktree", cmd_worktree, RUN_SETUP },
 +	{ "worktree", cmd_worktree, RUN_SETUP | NO_PARSEOPT },
  	{ "write-tree", cmd_write_tree, RUN_SETUP },
  };
  
@@@ -508,15 -506,11 +510,15 @@@ int is_builtin(const char *s
  	return !!get_builtin(s);
  }
  
 -static void list_builtins(void)
 +static void list_builtins(unsigned int exclude_option, char sep)
  {
  	int i;
 -	for (i = 0; i < ARRAY_SIZE(commands); i++)
 -		printf("%s\n", commands[i].cmd);
 +	for (i = 0; i < ARRAY_SIZE(commands); i++) {
 +		if (exclude_option &&
 +		    (commands[i].option & exclude_option))
 +			continue;
 +		printf("%s%c", commands[i].cmd, sep);
 +	}
  }
  
  #ifdef STRIP_EXTENSION
@@@ -692,8 -686,8 +694,8 @@@ int cmd_main(int argc, const char **arg
  		if (errno != ENOENT)
  			break;
  		if (was_alias) {
 -			fprintf(stderr, "Expansion of alias '%s' failed; "
 -				"'%s' is not a git command\n",
 +			fprintf(stderr, _("expansion of alias '%s' failed; "
 +					  "'%s' is not a git command\n"),
  				cmd, argv[0]);
  			exit(1);
  		}
@@@ -704,7 -698,7 +706,7 @@@
  			break;
  	}
  
 -	fprintf(stderr, "Failed to run command '%s': %s\n",
 +	fprintf(stderr, _("failed to run command '%s': %s\n"),
  		cmd, strerror(errno));
  
  	return 1;
diff --combined http-backend.c
index 88d2a9bc40,5d241e9109..bf9b9199e1
--- a/http-backend.c
+++ b/http-backend.c
@@@ -1,6 -1,5 +1,6 @@@
  #include "cache.h"
  #include "config.h"
 +#include "repository.h"
  #include "refs.h"
  #include "pkt-line.h"
  #include "object.h"
@@@ -11,7 -10,7 +11,8 @@@
  #include "url.h"
  #include "argv-array.h"
  #include "packfile.h"
 +#include "object-store.h"
+ #include "protocol.h"
  
  static const char content_type[] = "Content-Type";
  static const char content_length[] = "Content-Length";
@@@ -468,8 -467,11 +469,11 @@@ static void get_info_refs(struct strbu
  		hdr_str(hdr, content_type, buf.buf);
  		end_headers(hdr);
  
- 		packet_write_fmt(1, "# service=git-%s\n", svc->name);
- 		packet_flush(1);
+ 
+ 		if (determine_protocol_version_server() != protocol_v2) {
+ 			packet_write_fmt(1, "# service=git-%s\n", svc->name);
+ 			packet_flush(1);
+ 		}
  
  		argv[0] = svc->name;
  		run_service(argv, 0);
@@@ -519,13 -521,14 +523,13 @@@ static void get_info_packs(struct strbu
  	size_t cnt = 0;
  
  	select_getanyfile(hdr);
 -	prepare_packed_git();
 -	for (p = packed_git; p; p = p->next) {
 +	for (p = get_packed_git(the_repository); p; p = p->next) {
  		if (p->pack_local)
  			cnt++;
  	}
  
  	strbuf_grow(&buf, cnt * 53 + 2);
 -	for (p = packed_git; p; p = p->next) {
 +	for (p = get_packed_git(the_repository); p; p = p->next) {
  		if (p->pack_local)
  			strbuf_addf(&buf, "P %s\n", p->pack_name + objdirlen + 6);
  	}
diff --combined http.c
index 3034d10b68,531c59d21e..fed13b2169
--- a/http.c
+++ b/http.c
@@@ -13,12 -13,8 +13,12 @@@
  #include "transport.h"
  #include "packfile.h"
  #include "protocol.h"
 +#include "string-list.h"
 +#include "object-store.h"
  
  static struct trace_key trace_curl = TRACE_KEY_INIT(CURL);
 +static int trace_curl_data = 1;
 +static struct string_list cookies_to_redact = STRING_LIST_INIT_DUP;
  #if LIBCURL_VERSION_NUM >= 0x070a08
  long int git_curl_ipresolve = CURL_IPRESOLVE_WHATEVER;
  #else
@@@ -63,9 -59,6 +63,9 @@@ static struct 
  	{ "tlsv1.1", CURL_SSLVERSION_TLSv1_1 },
  	{ "tlsv1.2", CURL_SSLVERSION_TLSv1_2 },
  #endif
 +#if LIBCURL_VERSION_NUM >= 0x073400
 +	{ "tlsv1.3", CURL_SSLVERSION_TLSv1_3 },
 +#endif
  };
  #if LIBCURL_VERSION_NUM >= 0x070903
  static const char *ssl_key;
@@@ -73,9 -66,6 +73,9 @@@
  #if LIBCURL_VERSION_NUM >= 0x070908
  static const char *ssl_capath;
  #endif
 +#if LIBCURL_VERSION_NUM >= 0x071304
 +static const char *curl_no_proxy;
 +#endif
  #if LIBCURL_VERSION_NUM >= 0x072c00
  static const char *ssl_pinnedkey;
  #endif
@@@ -84,6 -74,7 +84,6 @@@ static long curl_low_speed_limit = -1
  static long curl_low_speed_time = -1;
  static int curl_ftp_no_epsv;
  static const char *curl_http_proxy;
 -static const char *curl_no_proxy;
  static const char *http_proxy_authmethod;
  static struct {
  	const char *name;
@@@ -584,54 -575,6 +584,54 @@@ static void redact_sensitive_header(str
  		/* Everything else is opaque and possibly sensitive */
  		strbuf_setlen(header,  sensitive_header - header->buf);
  		strbuf_addstr(header, " <redacted>");
 +	} else if (cookies_to_redact.nr &&
 +		   skip_prefix(header->buf, "Cookie:", &sensitive_header)) {
 +		struct strbuf redacted_header = STRBUF_INIT;
 +		char *cookie;
 +
 +		while (isspace(*sensitive_header))
 +			sensitive_header++;
 +
 +		/*
 +		 * The contents of header starting from sensitive_header will
 +		 * subsequently be overridden, so it is fine to mutate this
 +		 * string (hence the assignment to "char *").
 +		 */
 +		cookie = (char *) sensitive_header;
 +
 +		while (cookie) {
 +			char *equals;
 +			char *semicolon = strstr(cookie, "; ");
 +			if (semicolon)
 +				*semicolon = 0;
 +			equals = strchrnul(cookie, '=');
 +			if (!equals) {
 +				/* invalid cookie, just append and continue */
 +				strbuf_addstr(&redacted_header, cookie);
 +				continue;
 +			}
 +			*equals = 0; /* temporarily set to NUL for lookup */
 +			if (string_list_lookup(&cookies_to_redact, cookie)) {
 +				strbuf_addstr(&redacted_header, cookie);
 +				strbuf_addstr(&redacted_header, "=<redacted>");
 +			} else {
 +				*equals = '=';
 +				strbuf_addstr(&redacted_header, cookie);
 +			}
 +			if (semicolon) {
 +				/*
 +				 * There are more cookies. (Or, for some
 +				 * reason, the input string ends in "; ".)
 +				 */
 +				strbuf_addstr(&redacted_header, "; ");
 +				cookie = semicolon + strlen("; ");
 +			} else {
 +				cookie = NULL;
 +			}
 +		}
 +
 +		strbuf_setlen(header, sensitive_header - header->buf);
 +		strbuf_addbuf(header, &redacted_header);
  	}
  }
  
@@@ -702,32 -645,24 +702,32 @@@ static int curl_trace(CURL *handle, cur
  		curl_dump_header(text, (unsigned char *)data, size, DO_FILTER);
  		break;
  	case CURLINFO_DATA_OUT:
 -		text = "=> Send data";
 -		curl_dump_data(text, (unsigned char *)data, size);
 +		if (trace_curl_data) {
 +			text = "=> Send data";
 +			curl_dump_data(text, (unsigned char *)data, size);
 +		}
  		break;
  	case CURLINFO_SSL_DATA_OUT:
 -		text = "=> Send SSL data";
 -		curl_dump_data(text, (unsigned char *)data, size);
 +		if (trace_curl_data) {
 +			text = "=> Send SSL data";
 +			curl_dump_data(text, (unsigned char *)data, size);
 +		}
  		break;
  	case CURLINFO_HEADER_IN:
  		text = "<= Recv header";
  		curl_dump_header(text, (unsigned char *)data, size, NO_FILTER);
  		break;
  	case CURLINFO_DATA_IN:
 -		text = "<= Recv data";
 -		curl_dump_data(text, (unsigned char *)data, size);
 +		if (trace_curl_data) {
 +			text = "<= Recv data";
 +			curl_dump_data(text, (unsigned char *)data, size);
 +		}
  		break;
  	case CURLINFO_SSL_DATA_IN:
 -		text = "<= Recv SSL data";
 -		curl_dump_data(text, (unsigned char *)data, size);
 +		if (trace_curl_data) {
 +			text = "<= Recv SSL data";
 +			curl_dump_data(text, (unsigned char *)data, size);
 +		}
  		break;
  
  	default:		/* we ignore unknown types by default */
@@@ -872,13 -807,6 +872,13 @@@ static CURL *get_curl_handle(void
  	if (getenv("GIT_CURL_VERBOSE"))
  		curl_easy_setopt(result, CURLOPT_VERBOSE, 1L);
  	setup_curl_trace(result);
 +	if (getenv("GIT_TRACE_CURL_NO_DATA"))
 +		trace_curl_data = 0;
 +	if (getenv("GIT_REDACT_COOKIES")) {
 +		string_list_split(&cookies_to_redact,
 +				  getenv("GIT_REDACT_COOKIES"), ',', -1);
 +		string_list_sort(&cookies_to_redact);
 +	}
  
  	curl_easy_setopt(result, CURLOPT_USERAGENT,
  		user_agent ? user_agent : git_user_agent());
@@@ -976,21 -904,6 +976,6 @@@ static void set_from_env(const char **v
  		*var = val;
  }
  
- static void protocol_http_header(void)
- {
- 	if (get_protocol_version_config() > 0) {
- 		struct strbuf protocol_header = STRBUF_INIT;
- 
- 		strbuf_addf(&protocol_header, GIT_PROTOCOL_HEADER ": version=%d",
- 			    get_protocol_version_config());
- 
- 
- 		extra_http_headers = curl_slist_append(extra_http_headers,
- 						       protocol_header.buf);
- 		strbuf_release(&protocol_header);
- 	}
- }
- 
  void http_init(struct remote *remote, const char *url, int proactive_auth)
  {
  	char *low_speed_limit;
@@@ -1021,8 -934,6 +1006,6 @@@
  	if (remote)
  		var_override(&http_proxy_authmethod, remote->http_proxy_authmethod);
  
- 	protocol_http_header();
- 
  	pragma_header = curl_slist_append(http_copy_default_headers(),
  		"Pragma: no-cache");
  	no_pragma_header = curl_slist_append(http_copy_default_headers(),
@@@ -1266,14 -1177,14 +1249,14 @@@ static struct fill_chain *fill_cfg
  
  void add_fill_function(void *data, int (*fill)(void *))
  {
 -	struct fill_chain *new = xmalloc(sizeof(*new));
 +	struct fill_chain *new_fill = xmalloc(sizeof(*new_fill));
  	struct fill_chain **linkp = &fill_cfg;
 -	new->data = data;
 -	new->fill = fill;
 -	new->next = NULL;
 +	new_fill->data = data;
 +	new_fill->fill = fill;
 +	new_fill->next = NULL;
  	while (*linkp)
  		linkp = &(*linkp)->next;
 -	*linkp = new;
 +	*linkp = new_fill;
  }
  
  void fill_active_slots(void)
@@@ -1795,6 -1706,14 +1778,14 @@@ static int http_request(const char *url
  
  	headers = curl_slist_append(headers, buf.buf);
  
+ 	/* Add additional headers here */
+ 	if (options && options->extra_headers) {
+ 		const struct string_list_item *item;
+ 		for_each_string_list_item(item, options->extra_headers) {
+ 			headers = curl_slist_append(headers, item->string);
+ 		}
+ 	}
+ 
  	curl_easy_setopt(slot->curl, CURLOPT_URL, url);
  	curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, headers);
  	curl_easy_setopt(slot->curl, CURLOPT_ENCODING, "gzip");
@@@ -2102,6 -2021,7 +2093,6 @@@ int finish_http_pack_request(struct htt
  	char *tmp_idx;
  	size_t len;
  	struct child_process ip = CHILD_PROCESS_INIT;
 -	const char *ip_argv[8];
  
  	close_pack_index(p);
  
@@@ -2117,9 -2037,13 +2108,9 @@@
  		die("BUG: pack tmpfile does not end in .pack.temp?");
  	tmp_idx = xstrfmt("%.*s.idx.temp", (int)len, preq->tmpfile);
  
 -	ip_argv[0] = "index-pack";
 -	ip_argv[1] = "-o";
 -	ip_argv[2] = tmp_idx;
 -	ip_argv[3] = preq->tmpfile;
 -	ip_argv[4] = NULL;
 -
 -	ip.argv = ip_argv;
 +	argv_array_push(&ip.args, "index-pack");
 +	argv_array_pushl(&ip.args, "-o", tmp_idx, NULL);
 +	argv_array_push(&ip.args, preq->tmpfile);
  	ip.git_cmd = 1;
  	ip.no_stdin = 1;
  	ip.no_stdout = 1;
@@@ -2139,7 -2063,7 +2130,7 @@@
  		return -1;
  	}
  
 -	install_packed_git(p);
 +	install_packed_git(the_repository, p);
  	free(tmp_idx);
  	return 0;
  }
@@@ -2240,7 -2164,7 +2231,7 @@@ struct http_object_request *new_http_ob
  	unsigned char *sha1)
  {
  	char *hex = sha1_to_hex(sha1);
 -	const char *filename;
 +	struct strbuf filename = STRBUF_INIT;
  	char prevfile[PATH_MAX];
  	int prevlocal;
  	char prev_buf[PREV_BUF_SIZE];
@@@ -2252,15 -2176,14 +2243,15 @@@
  	hashcpy(freq->sha1, sha1);
  	freq->localfile = -1;
  
 -	filename = sha1_file_name(sha1);
 +	sha1_file_name(the_repository, &filename, sha1);
  	snprintf(freq->tmpfile, sizeof(freq->tmpfile),
 -		 "%s.temp", filename);
 +		 "%s.temp", filename.buf);
  
 -	snprintf(prevfile, sizeof(prevfile), "%s.prev", filename);
 +	snprintf(prevfile, sizeof(prevfile), "%s.prev", filename.buf);
  	unlink_or_warn(prevfile);
  	rename(freq->tmpfile, prevfile);
  	unlink_or_warn(freq->tmpfile);
 +	strbuf_release(&filename);
  
  	if (freq->localfile != -1)
  		error("fd leakage in start: %d", freq->localfile);
@@@ -2375,7 -2298,6 +2366,7 @@@ void process_http_object_request(struc
  int finish_http_object_request(struct http_object_request *freq)
  {
  	struct stat st;
 +	struct strbuf filename = STRBUF_INIT;
  
  	close(freq->localfile);
  	freq->localfile = -1;
@@@ -2401,9 -2323,8 +2392,9 @@@
  		unlink_or_warn(freq->tmpfile);
  		return -1;
  	}
 -	freq->rename =
 -		finalize_object_file(freq->tmpfile, sha1_file_name(freq->sha1));
 +	sha1_file_name(the_repository, &filename, freq->sha1);
 +	freq->rename = finalize_object_file(freq->tmpfile, filename.buf);
 +	strbuf_release(&filename);
  
  	return freq->rename;
  }
diff --combined refs.c
index 8b7a77fe5e,cefbad2076..10f69da2b8
--- a/refs.c
+++ b/refs.c
@@@ -13,6 -13,7 +13,7 @@@
  #include "tag.h"
  #include "submodule.h"
  #include "worktree.h"
+ #include "argv-array.h"
  
  /*
   * List of all available backends
@@@ -301,7 -302,7 +302,7 @@@ enum peel_status peel_object(const stru
  	struct object *o = lookup_unknown_object(name->hash);
  
  	if (o->type == OBJ_NONE) {
 -		int type = sha1_object_info(name->hash, NULL);
 +		int type = oid_object_info(name, NULL);
  		if (type < 0 || !object_as_type(o, type, 0))
  			return PEEL_INVALID;
  	}
@@@ -501,6 -502,19 +502,19 @@@ int refname_match(const char *abbrev_na
  	return 0;
  }
  
+ /*
+  * Given a 'prefix' expand it by the rules in 'ref_rev_parse_rules' and add
+  * the results to 'prefixes'
+  */
+ void expand_ref_prefix(struct argv_array *prefixes, const char *prefix)
+ {
+ 	const char **p;
+ 	int len = strlen(prefix);
+ 
+ 	for (p = ref_rev_parse_rules; *p; p++)
+ 		argv_array_pushf(prefixes, *p, len, prefix);
+ }
+ 
  /*
   * *string and *len will only be substituted, and *string returned (for
   * later free()ing) if the string passed in is a magic short-hand form
diff --combined remote-curl.c
index a7c4c9b5ff,595447b16e..4f779eee54
--- a/remote-curl.c
+++ b/remote-curl.c
@@@ -1,6 -1,7 +1,7 @@@
  #include "cache.h"
  #include "config.h"
  #include "remote.h"
+ #include "connect.h"
  #include "strbuf.h"
  #include "walker.h"
  #include "http.h"
@@@ -13,7 -14,7 +14,8 @@@
  #include "credential.h"
  #include "sha1-array.h"
  #include "send-pack.h"
+ #include "protocol.h"
 +#include "quote.h"
  
  static struct remote *remote;
  /* always ends with a trailing slash */
@@@ -25,7 -26,6 +27,7 @@@ struct options 
  	char *deepen_since;
  	struct string_list deepen_not;
  	struct string_list push_options;
 +	char *filter;
  	unsigned progress : 1,
  		check_self_contained_and_connected : 1,
  		cloning : 1,
@@@ -35,9 -35,7 +37,9 @@@
  		thin : 1,
  		/* One of the SEND_PACK_PUSH_CERT_* constants. */
  		push_cert : 2,
 -		deepen_relative : 1;
 +		deepen_relative : 1,
 +		from_promisor : 1,
 +		no_dependents : 1;
  };
  static struct options options;
  static struct string_list cas_options = STRING_LIST_INIT_DUP;
@@@ -146,15 -144,7 +148,15 @@@ static int set_option(const char *name
  			return -1;
  		return 0;
  	} else if (!strcmp(name, "push-option")) {
 -		string_list_append(&options.push_options, value);
 +		if (*value != '"')
 +			string_list_append(&options.push_options, value);
 +		else {
 +			struct strbuf unquoted = STRBUF_INIT;
 +			if (unquote_c_style(&unquoted, value, NULL) < 0)
 +				die("invalid quoting in push-option value");
 +			string_list_append_nodup(&options.push_options,
 +						 strbuf_detach(&unquoted, NULL));
 +		}
  		return 0;
  
  #if LIBCURL_VERSION_NUM >= 0x070a08
@@@ -169,27 -159,19 +171,28 @@@
  			return -1;
  		return 0;
  #endif /* LIBCURL_VERSION_NUM >= 0x070a08 */
 +	} else if (!strcmp(name, "from-promisor")) {
 +		options.from_promisor = 1;
 +		return 0;
 +	} else if (!strcmp(name, "no-dependents")) {
 +		options.no_dependents = 1;
 +		return 0;
 +	} else if (!strcmp(name, "filter")) {
 +		options.filter = xstrdup(value);;
 +		return 0;
  	} else {
  		return 1 /* unsupported */;
  	}
  }
  
  struct discovery {
- 	const char *service;
+ 	char *service;
  	char *buf_alloc;
  	char *buf;
  	size_t len;
  	struct ref *refs;
  	struct oid_array shallow;
+ 	enum protocol_version version;
  	unsigned proto_git : 1;
  };
  static struct discovery *last_discovery;
@@@ -197,8 -179,31 +200,31 @@@
  static struct ref *parse_git_refs(struct discovery *heads, int for_push)
  {
  	struct ref *list = NULL;
- 	get_remote_heads(-1, heads->buf, heads->len, &list,
- 			 for_push ? REF_NORMAL : 0, NULL, &heads->shallow);
+ 	struct packet_reader reader;
+ 
+ 	packet_reader_init(&reader, -1, heads->buf, heads->len,
+ 			   PACKET_READ_CHOMP_NEWLINE |
+ 			   PACKET_READ_GENTLE_ON_EOF);
+ 
+ 	heads->version = discover_version(&reader);
+ 	switch (heads->version) {
+ 	case protocol_v2:
+ 		/*
+ 		 * Do nothing.  This isn't a list of refs but rather a
+ 		 * capability advertisement.  Client would have run
+ 		 * 'stateless-connect' so we'll dump this capability listing
+ 		 * and let them request the refs themselves.
+ 		 */
+ 		break;
+ 	case protocol_v1:
+ 	case protocol_v0:
+ 		get_remote_heads(&reader, &list, for_push ? REF_NORMAL : 0,
+ 				 NULL, &heads->shallow);
+ 		break;
+ 	case protocol_unknown_version:
+ 		BUG("unknown protocol version");
+ 	}
+ 
  	return list;
  }
  
@@@ -259,6 -264,7 +285,7 @@@ static void free_discovery(struct disco
  		free(d->shallow.oid);
  		free(d->buf_alloc);
  		free_refs(d->refs);
+ 		free(d->service);
  		free(d);
  	}
  }
@@@ -290,6 -296,19 +317,19 @@@ static int show_http_message(struct str
  	return 0;
  }
  
+ static int get_protocol_http_header(enum protocol_version version,
+ 				    struct strbuf *header)
+ {
+ 	if (version > 0) {
+ 		strbuf_addf(header, GIT_PROTOCOL_HEADER ": version=%d",
+ 			    version);
+ 
+ 		return 1;
+ 	}
+ 
+ 	return 0;
+ }
+ 
  static struct discovery *discover_refs(const char *service, int for_push)
  {
  	struct strbuf exp = STRBUF_INIT;
@@@ -298,9 -317,12 +338,12 @@@
  	struct strbuf buffer = STRBUF_INIT;
  	struct strbuf refs_url = STRBUF_INIT;
  	struct strbuf effective_url = STRBUF_INIT;
+ 	struct strbuf protocol_header = STRBUF_INIT;
+ 	struct string_list extra_headers = STRING_LIST_INIT_DUP;
  	struct discovery *last = last_discovery;
  	int http_ret, maybe_smart = 0;
  	struct http_get_options http_options;
+ 	enum protocol_version version = get_protocol_version_config();
  
  	if (last && !strcmp(service, last->service))
  		return last;
@@@ -317,11 -339,24 +360,24 @@@
  		strbuf_addf(&refs_url, "service=%s", service);
  	}
  
+ 	/*
+ 	 * NEEDSWORK: If we are trying to use protocol v2 and we are planning
+ 	 * to perform a push, then fallback to v0 since the client doesn't know
+ 	 * how to push yet using v2.
+ 	 */
+ 	if (version == protocol_v2 && !strcmp("git-receive-pack", service))
+ 		version = protocol_v0;
+ 
+ 	/* Add the extra Git-Protocol header */
+ 	if (get_protocol_http_header(version, &protocol_header))
+ 		string_list_append(&extra_headers, protocol_header.buf);
+ 
  	memset(&http_options, 0, sizeof(http_options));
  	http_options.content_type = &type;
  	http_options.charset = &charset;
  	http_options.effective_url = &effective_url;
  	http_options.base_url = &url;
+ 	http_options.extra_headers = &extra_headers;
  	http_options.initial_request = 1;
  	http_options.no_cache = 1;
  	http_options.keep_error = 1;
@@@ -345,7 -380,7 +401,7 @@@
  		warning(_("redirecting to %s"), url.buf);
  
  	last= xcalloc(1, sizeof(*last_discovery));
- 	last->service = service;
+ 	last->service = xstrdup(service);
  	last->buf_alloc = strbuf_detach(&buffer, &last->len);
  	last->buf = last->buf_alloc;
  
@@@ -360,8 -395,6 +416,8 @@@
  		 * pkt-line matches our request.
  		 */
  		line = packet_read_line_buf(&last->buf, &last->len, NULL);
 +		if (!line)
 +			die("invalid server response; expected service, got flush packet");
  
  		strbuf_reset(&exp);
  		strbuf_addf(&exp, "# service=%s", service);
@@@ -377,6 -410,9 +433,9 @@@
  			;
  
  		last->proto_git = 1;
+ 	} else if (maybe_smart &&
+ 		   last->len > 5 && starts_with(last->buf + 4, "version 2")) {
+ 		last->proto_git = 1;
  	}
  
  	if (last->proto_git)
@@@ -390,6 -426,8 +449,8 @@@
  	strbuf_release(&charset);
  	strbuf_release(&effective_url);
  	strbuf_release(&buffer);
+ 	strbuf_release(&protocol_header);
+ 	string_list_clear(&extra_headers, 0);
  	last_discovery = last;
  	return last;
  }
@@@ -426,6 -464,7 +487,7 @@@ struct rpc_state 
  	char *service_url;
  	char *hdr_content_type;
  	char *hdr_accept;
+ 	char *protocol_header;
  	char *buf;
  	size_t alloc;
  	size_t len;
@@@ -612,6 -651,10 +674,10 @@@ static int post_rpc(struct rpc_state *r
  	headers = curl_slist_append(headers, needs_100_continue ?
  		"Expect: 100-continue" : "Expect:");
  
+ 	/* Add the extra Git-Protocol header */
+ 	if (rpc->protocol_header)
+ 		headers = curl_slist_append(headers, rpc->protocol_header);
+ 
  retry:
  	slot = get_active_slot();
  
@@@ -752,6 -795,11 +818,11 @@@ static int rpc_service(struct rpc_stat
  	strbuf_addf(&buf, "Accept: application/x-%s-result", svc);
  	rpc->hdr_accept = strbuf_detach(&buf, NULL);
  
+ 	if (get_protocol_http_header(heads->version, &buf))
+ 		rpc->protocol_header = strbuf_detach(&buf, NULL);
+ 	else
+ 		rpc->protocol_header = NULL;
+ 
  	while (!err) {
  		int n = packet_read(rpc->out, NULL, NULL, rpc->buf, rpc->alloc, 0);
  		if (!n)
@@@ -779,6 -827,7 +850,7 @@@
  	free(rpc->service_url);
  	free(rpc->hdr_content_type);
  	free(rpc->hdr_accept);
+ 	free(rpc->protocol_header);
  	free(rpc->buf);
  	strbuf_release(&buf);
  	return err;
@@@ -845,12 -894,6 +917,12 @@@ static int fetch_git(struct discovery *
  				 options.deepen_not.items[i].string);
  	if (options.deepen_relative && options.depth)
  		argv_array_push(&args, "--deepen-relative");
 +	if (options.from_promisor)
 +		argv_array_push(&args, "--from-promisor");
 +	if (options.no_dependents)
 +		argv_array_push(&args, "--no-dependents");
 +	if (options.filter)
 +		argv_array_pushf(&args, "--filter=%s", options.filter);
  	argv_array_push(&args, url.buf);
  
  	for (i = 0; i < nr_heads; i++) {
@@@ -1056,6 -1099,202 +1128,202 @@@ static void parse_push(struct strbuf *b
  	free(specs);
  }
  
+ /*
+  * Used to represent the state of a connection to an HTTP server when
+  * communicating using git's wire-protocol version 2.
+  */
+ struct proxy_state {
+ 	char *service_name;
+ 	char *service_url;
+ 	struct curl_slist *headers;
+ 	struct strbuf request_buffer;
+ 	int in;
+ 	int out;
+ 	struct packet_reader reader;
+ 	size_t pos;
+ 	int seen_flush;
+ };
+ 
+ static void proxy_state_init(struct proxy_state *p, const char *service_name,
+ 			     enum protocol_version version)
+ {
+ 	struct strbuf buf = STRBUF_INIT;
+ 
+ 	memset(p, 0, sizeof(*p));
+ 	p->service_name = xstrdup(service_name);
+ 
+ 	p->in = 0;
+ 	p->out = 1;
+ 	strbuf_init(&p->request_buffer, 0);
+ 
+ 	strbuf_addf(&buf, "%s%s", url.buf, p->service_name);
+ 	p->service_url = strbuf_detach(&buf, NULL);
+ 
+ 	p->headers = http_copy_default_headers();
+ 
+ 	strbuf_addf(&buf, "Content-Type: application/x-%s-request", p->service_name);
+ 	p->headers = curl_slist_append(p->headers, buf.buf);
+ 	strbuf_reset(&buf);
+ 
+ 	strbuf_addf(&buf, "Accept: application/x-%s-result", p->service_name);
+ 	p->headers = curl_slist_append(p->headers, buf.buf);
+ 	strbuf_reset(&buf);
+ 
+ 	p->headers = curl_slist_append(p->headers, "Transfer-Encoding: chunked");
+ 
+ 	/* Add the Git-Protocol header */
+ 	if (get_protocol_http_header(version, &buf))
+ 		p->headers = curl_slist_append(p->headers, buf.buf);
+ 
+ 	packet_reader_init(&p->reader, p->in, NULL, 0,
+ 			   PACKET_READ_GENTLE_ON_EOF);
+ 
+ 	strbuf_release(&buf);
+ }
+ 
+ static void proxy_state_clear(struct proxy_state *p)
+ {
+ 	free(p->service_name);
+ 	free(p->service_url);
+ 	curl_slist_free_all(p->headers);
+ 	strbuf_release(&p->request_buffer);
+ }
+ 
+ /*
+  * CURLOPT_READFUNCTION callback function.
+  * Attempts to copy over a single packet-line at a time into the
+  * curl provided buffer.
+  */
+ static size_t proxy_in(char *buffer, size_t eltsize,
+ 		       size_t nmemb, void *userdata)
+ {
+ 	size_t max;
+ 	struct proxy_state *p = userdata;
+ 	size_t avail = p->request_buffer.len - p->pos;
+ 
+ 
+ 	if (eltsize != 1)
+ 		BUG("curl read callback called with size = %"PRIuMAX" != 1",
+ 		    (uintmax_t)eltsize);
+ 	max = nmemb;
+ 
+ 	if (!avail) {
+ 		if (p->seen_flush) {
+ 			p->seen_flush = 0;
+ 			return 0;
+ 		}
+ 
+ 		strbuf_reset(&p->request_buffer);
+ 		switch (packet_reader_read(&p->reader)) {
+ 		case PACKET_READ_EOF:
+ 			die("unexpected EOF when reading from parent process");
+ 		case PACKET_READ_NORMAL:
+ 			packet_buf_write_len(&p->request_buffer, p->reader.line,
+ 					     p->reader.pktlen);
+ 			break;
+ 		case PACKET_READ_DELIM:
+ 			packet_buf_delim(&p->request_buffer);
+ 			break;
+ 		case PACKET_READ_FLUSH:
+ 			packet_buf_flush(&p->request_buffer);
+ 			p->seen_flush = 1;
+ 			break;
+ 		}
+ 		p->pos = 0;
+ 		avail = p->request_buffer.len;
+ 	}
+ 
+ 	if (max < avail)
+ 		avail = max;
+ 	memcpy(buffer, p->request_buffer.buf + p->pos, avail);
+ 	p->pos += avail;
+ 	return avail;
+ }
+ 
+ static size_t proxy_out(char *buffer, size_t eltsize,
+ 			size_t nmemb, void *userdata)
+ {
+ 	size_t size;
+ 	struct proxy_state *p = userdata;
+ 
+ 	if (eltsize != 1)
+ 		BUG("curl read callback called with size = %"PRIuMAX" != 1",
+ 		    (uintmax_t)eltsize);
+ 	size = nmemb;
+ 
+ 	write_or_die(p->out, buffer, size);
+ 	return size;
+ }
+ 
+ /* Issues a request to the HTTP server configured in `p` */
+ static int proxy_request(struct proxy_state *p)
+ {
+ 	struct active_request_slot *slot;
+ 
+ 	slot = get_active_slot();
+ 
+ 	curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 0);
+ 	curl_easy_setopt(slot->curl, CURLOPT_POST, 1);
+ 	curl_easy_setopt(slot->curl, CURLOPT_URL, p->service_url);
+ 	curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, p->headers);
+ 
+ 	/* Setup function to read request from client */
+ 	curl_easy_setopt(slot->curl, CURLOPT_READFUNCTION, proxy_in);
+ 	curl_easy_setopt(slot->curl, CURLOPT_READDATA, p);
+ 
+ 	/* Setup function to write server response to client */
+ 	curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, proxy_out);
+ 	curl_easy_setopt(slot->curl, CURLOPT_WRITEDATA, p);
+ 
+ 	if (run_slot(slot, NULL) != HTTP_OK)
+ 		return -1;
+ 
+ 	return 0;
+ }
+ 
+ static int stateless_connect(const char *service_name)
+ {
+ 	struct discovery *discover;
+ 	struct proxy_state p;
+ 
+ 	/*
+ 	 * Run the info/refs request and see if the server supports protocol
+ 	 * v2.  If and only if the server supports v2 can we successfully
+ 	 * establish a stateless connection, otherwise we need to tell the
+ 	 * client to fallback to using other transport helper functions to
+ 	 * complete their request.
+ 	 */
+ 	discover = discover_refs(service_name, 0);
+ 	if (discover->version != protocol_v2) {
+ 		printf("fallback\n");
+ 		fflush(stdout);
+ 		return -1;
+ 	} else {
+ 		/* Stateless Connection established */
+ 		printf("\n");
+ 		fflush(stdout);
+ 	}
+ 
+ 	proxy_state_init(&p, service_name, discover->version);
+ 
+ 	/*
+ 	 * Dump the capability listing that we got from the server earlier
+ 	 * during the info/refs request.
+ 	 */
+ 	write_or_die(p.out, discover->buf, discover->len);
+ 
+ 	/* Peek the next packet line.  Until we see EOF keep sending POSTs */
+ 	while (packet_reader_peek(&p.reader) != PACKET_READ_EOF) {
+ 		if (proxy_request(&p)) {
+ 			/* We would have an err here */
+ 			break;
+ 		}
+ 	}
+ 
+ 	proxy_state_clear(&p);
+ 	return 0;
+ }
+ 
  int cmd_main(int argc, const char **argv)
  {
  	struct strbuf buf = STRBUF_INIT;
@@@ -1124,12 -1363,16 +1392,16 @@@
  			fflush(stdout);
  
  		} else if (!strcmp(buf.buf, "capabilities")) {
+ 			printf("stateless-connect\n");
  			printf("fetch\n");
  			printf("option\n");
  			printf("push\n");
  			printf("check-connectivity\n");
  			printf("\n");
  			fflush(stdout);
+ 		} else if (skip_prefix(buf.buf, "stateless-connect ", &arg)) {
+ 			if (!stateless_connect(arg))
+ 				break;
  		} else {
  			error("remote-curl: unknown command '%s' from git", buf.buf);
  			return 1;
diff --combined remote.h
index f09c01969d,368ba221cc..2b3180f94d
--- a/remote.h
+++ b/remote.h
@@@ -47,7 -47,6 +47,7 @@@ struct remote 
  	int skip_default_update;
  	int mirror;
  	int prune;
 +	int prune_tags;
  
  	const char *receivepack;
  	const char *uploadpack;
@@@ -151,10 -150,17 +151,17 @@@ int check_ref_type(const struct ref *re
  void free_refs(struct ref *ref);
  
  struct oid_array;
- extern struct ref **get_remote_heads(int in, char *src_buf, size_t src_len,
+ struct packet_reader;
+ struct argv_array;
+ extern struct ref **get_remote_heads(struct packet_reader *reader,
  				     struct ref **list, unsigned int flags,
  				     struct oid_array *extra_have,
- 				     struct oid_array *shallow);
+ 				     struct oid_array *shallow_points);
+ 
+ /* Used for protocol v2 in order to retrieve refs from a remote */
+ extern struct ref **get_remote_refs(int fd_out, struct packet_reader *reader,
+ 				    struct ref **list, int for_push,
+ 				    const struct argv_array *ref_prefixes);
  
  int resolve_remote_symref(struct ref *ref, struct ref *list);
  int ref_newer(const struct object_id *new_oid, const struct object_id *old_oid);
@@@ -258,18 -264,10 +265,18 @@@ enum match_refs_flags 
  	MATCH_REFS_FOLLOW_TAGS	= (1 << 3)
  };
  
 +/* Flags for --ahead-behind option. */
 +enum ahead_behind_flags {
 +	AHEAD_BEHIND_UNSPECIFIED = -1,
 +	AHEAD_BEHIND_QUICK       =  0,  /* just eq/neq reporting */
 +	AHEAD_BEHIND_FULL        =  1,  /* traditional a/b reporting */
 +};
 +
  /* Reporting of tracking info */
  int stat_tracking_info(struct branch *branch, int *num_ours, int *num_theirs,
 -		       const char **upstream_name);
 -int format_tracking_info(struct branch *branch, struct strbuf *sb);
 +		       const char **upstream_name, enum ahead_behind_flags abf);
 +int format_tracking_info(struct branch *branch, struct strbuf *sb,
 +			 enum ahead_behind_flags abf);
  
  struct ref *get_local_heads(void);
  /*
@@@ -306,8 -304,4 +313,8 @@@ extern int parseopt_push_cas_option(con
  extern int is_empty_cas(const struct push_cas_option *);
  void apply_push_cas(struct push_cas_option *, struct remote *, struct ref *);
  
 +#define TAG_REFSPEC "refs/tags/*:refs/tags/*"
 +
 +void add_prune_tags_to_fetch_refspec(struct remote *remote);
 +
  #endif
diff --combined transport-helper.c
index 3f380d87d9,aecbc4a845..11f1055b47
--- a/transport-helper.c
+++ b/transport-helper.c
@@@ -12,6 -12,7 +12,7 @@@
  #include "argv-array.h"
  #include "refs.h"
  #include "transport-internal.h"
+ #include "protocol.h"
  
  static int debug;
  
@@@ -26,6 -27,7 +27,7 @@@ struct helper_data 
  		option : 1,
  		push : 1,
  		connect : 1,
+ 		stateless_connect : 1,
  		signed_tags : 1,
  		check_connectivity : 1,
  		no_disconnect_req : 1,
@@@ -49,7 -51,7 +51,7 @@@ static void sendline(struct helper_dat
  		die_errno("Full write to remote helper failed");
  }
  
- static int recvline_fh(FILE *helper, struct strbuf *buffer, const char *name)
+ static int recvline_fh(FILE *helper, struct strbuf *buffer)
  {
  	strbuf_reset(buffer);
  	if (debug)
@@@ -67,7 -69,7 +69,7 @@@
  
  static int recvline(struct helper_data *helper, struct strbuf *buffer)
  {
- 	return recvline_fh(helper->out, buffer, helper->name);
+ 	return recvline_fh(helper->out, buffer);
  }
  
  static void write_constant(int fd, const char *str)
@@@ -188,6 -190,8 +190,8 @@@ static struct child_process *get_helper
  			refspecs[refspec_nr++] = xstrdup(arg);
  		} else if (!strcmp(capname, "connect")) {
  			data->connect = 1;
+ 		} else if (!strcmp(capname, "stateless-connect")) {
+ 			data->stateless_connect = 1;
  		} else if (!strcmp(capname, "signed-tags")) {
  			data->signed_tags = 1;
  		} else if (skip_prefix(capname, "export-marks ", &arg)) {
@@@ -545,14 -549,13 +549,13 @@@ static int fetch_with_import(struct tra
  	return 0;
  }
  
- static int process_connect_service(struct transport *transport,
- 				   const char *name, const char *exec)
+ static int run_connect(struct transport *transport, struct strbuf *cmdbuf)
  {
  	struct helper_data *data = transport->data;
- 	struct strbuf cmdbuf = STRBUF_INIT;
- 	struct child_process *helper;
- 	int r, duped, ret = 0;
+ 	int ret = 0;
+ 	int duped;
  	FILE *input;
+ 	struct child_process *helper;
  
  	helper = get_helper(transport);
  
@@@ -568,44 -571,61 +571,61 @@@
  	input = xfdopen(duped, "r");
  	setvbuf(input, NULL, _IONBF, 0);
  
+ 	sendline(data, cmdbuf);
+ 	if (recvline_fh(input, cmdbuf))
+ 		exit(128);
+ 
+ 	if (!strcmp(cmdbuf->buf, "")) {
+ 		data->no_disconnect_req = 1;
+ 		if (debug)
+ 			fprintf(stderr, "Debug: Smart transport connection "
+ 				"ready.\n");
+ 		ret = 1;
+ 	} else if (!strcmp(cmdbuf->buf, "fallback")) {
+ 		if (debug)
+ 			fprintf(stderr, "Debug: Falling back to dumb "
+ 				"transport.\n");
+ 	} else {
+ 		die("Unknown response to connect: %s",
+ 			cmdbuf->buf);
+ 	}
+ 
+ 	fclose(input);
+ 	return ret;
+ }
+ 
+ static int process_connect_service(struct transport *transport,
+ 				   const char *name, const char *exec)
+ {
+ 	struct helper_data *data = transport->data;
+ 	struct strbuf cmdbuf = STRBUF_INIT;
+ 	int ret = 0;
+ 
  	/*
  	 * Handle --upload-pack and friends. This is fire and forget...
  	 * just warn if it fails.
  	 */
  	if (strcmp(name, exec)) {
- 		r = set_helper_option(transport, "servpath", exec);
+ 		int r = set_helper_option(transport, "servpath", exec);
  		if (r > 0)
  			warning("Setting remote service path not supported by protocol.");
  		else if (r < 0)
  			warning("Invalid remote service path.");
  	}
  
- 	if (data->connect)
+ 	if (data->connect) {
  		strbuf_addf(&cmdbuf, "connect %s\n", name);
- 	else
- 		goto exit;
- 
- 	sendline(data, &cmdbuf);
- 	if (recvline_fh(input, &cmdbuf, name))
- 		exit(128);
- 
- 	if (!strcmp(cmdbuf.buf, "")) {
- 		data->no_disconnect_req = 1;
- 		if (debug)
- 			fprintf(stderr, "Debug: Smart transport connection "
- 				"ready.\n");
- 		ret = 1;
- 	} else if (!strcmp(cmdbuf.buf, "fallback")) {
- 		if (debug)
- 			fprintf(stderr, "Debug: Falling back to dumb "
- 				"transport.\n");
- 	} else
- 		die("Unknown response to connect: %s",
- 			cmdbuf.buf);
+ 		ret = run_connect(transport, &cmdbuf);
+ 	} else if (data->stateless_connect &&
+ 		   (get_protocol_version_config() == protocol_v2) &&
+ 		   !strcmp("git-upload-pack", name)) {
+ 		strbuf_addf(&cmdbuf, "stateless-connect %s\n", name);
+ 		ret = run_connect(transport, &cmdbuf);
+ 		if (ret)
+ 			transport->stateless_rpc = 1;
+ 	}
  
- exit:
  	strbuf_release(&cmdbuf);
- 	fclose(input);
  	return ret;
  }
  
@@@ -672,11 -692,6 +692,11 @@@ static int fetch(struct transport *tran
  	if (data->transport_options.update_shallow)
  		set_helper_option(transport, "update-shallow", "true");
  
 +	if (data->transport_options.filter_options.choice)
 +		set_helper_option(
 +			transport, "filter",
 +			data->transport_options.filter_options.filter_spec);
 +
  	if (data->fetch)
  		return fetch_with_fetch(transport, nr_heads, to_fetch);
  
@@@ -1031,7 -1046,8 +1051,8 @@@ static int has_attribute(const char *at
  	}
  }
  
- static struct ref *get_refs_list(struct transport *transport, int for_push)
+ static struct ref *get_refs_list(struct transport *transport, int for_push,
+ 				 const struct argv_array *ref_prefixes)
  {
  	struct helper_data *data = transport->data;
  	struct child_process *helper;
@@@ -1044,7 -1060,7 +1065,7 @@@
  
  	if (process_connect(transport, for_push)) {
  		do_take_over(transport);
- 		return transport->vtable->get_refs_list(transport, for_push);
+ 		return transport->vtable->get_refs_list(transport, for_push, ref_prefixes);
  	}
  
  	if (data->push && for_push)
diff --combined transport.c
index 94eccf29aa,342db492ca..16b2f54f22
--- a/transport.c
+++ b/transport.c
@@@ -18,7 -18,7 +18,8 @@@
  #include "sha1-array.h"
  #include "sigchain.h"
  #include "transport-internal.h"
+ #include "protocol.h"
 +#include "object-store.h"
  
  static void set_upstreams(struct transport *transport, struct ref *refs,
  	int pretend)
@@@ -72,7 -72,9 +73,9 @@@ struct bundle_transport_data 
  	struct bundle_header header;
  };
  
- static struct ref *get_refs_from_bundle(struct transport *transport, int for_push)
+ static struct ref *get_refs_from_bundle(struct transport *transport,
+ 					int for_push,
+ 					const struct argv_array *ref_prefixes)
  {
  	struct bundle_transport_data *data = transport->data;
  	struct ref *result = NULL;
@@@ -118,6 -120,7 +121,7 @@@ struct git_transport_data 
  	struct child_process *conn;
  	int fd[2];
  	unsigned got_remote_heads : 1;
+ 	enum protocol_version version;
  	struct oid_array extra_have;
  	struct oid_array shallow;
  };
@@@ -162,15 -165,6 +166,15 @@@ static int set_git_option(struct git_tr
  	} else if (!strcmp(name, TRANS_OPT_DEEPEN_RELATIVE)) {
  		opts->deepen_relative = !!value;
  		return 0;
 +	} else if (!strcmp(name, TRANS_OPT_FROM_PROMISOR)) {
 +		opts->from_promisor = !!value;
 +		return 0;
 +	} else if (!strcmp(name, TRANS_OPT_NO_DEPENDENTS)) {
 +		opts->no_dependents = !!value;
 +		return 0;
 +	} else if (!strcmp(name, TRANS_OPT_LIST_OBJECTS_FILTER)) {
 +		parse_list_objects_filter(&opts->filter_options, value);
 +		return 0;
  	}
  	return 1;
  }
@@@ -197,16 -191,35 +201,35 @@@ static int connect_setup(struct transpo
  	return 0;
  }
  
- static struct ref *get_refs_via_connect(struct transport *transport, int for_push)
+ static struct ref *get_refs_via_connect(struct transport *transport, int for_push,
+ 					const struct argv_array *ref_prefixes)
  {
  	struct git_transport_data *data = transport->data;
- 	struct ref *refs;
+ 	struct ref *refs = NULL;
+ 	struct packet_reader reader;
  
  	connect_setup(transport, for_push);
- 	get_remote_heads(data->fd[0], NULL, 0, &refs,
- 			 for_push ? REF_NORMAL : 0,
- 			 &data->extra_have,
- 			 &data->shallow);
+ 
+ 	packet_reader_init(&reader, data->fd[0], NULL, 0,
+ 			   PACKET_READ_CHOMP_NEWLINE |
+ 			   PACKET_READ_GENTLE_ON_EOF);
+ 
+ 	data->version = discover_version(&reader);
+ 	switch (data->version) {
+ 	case protocol_v2:
+ 		get_remote_refs(data->fd[1], &reader, &refs, for_push,
+ 				ref_prefixes);
+ 		break;
+ 	case protocol_v1:
+ 	case protocol_v0:
+ 		get_remote_heads(&reader, &refs,
+ 				 for_push ? REF_NORMAL : 0,
+ 				 &data->extra_have,
+ 				 &data->shallow);
+ 		break;
+ 	case protocol_unknown_version:
+ 		BUG("unknown protocol version");
+ 	}
  	data->got_remote_heads = 1;
  
  	return refs;
@@@ -217,7 -230,7 +240,7 @@@ static int fetch_refs_via_pack(struct t
  {
  	int ret = 0;
  	struct git_transport_data *data = transport->data;
- 	struct ref *refs;
+ 	struct ref *refs = NULL;
  	char *dest = xstrdup(transport->url);
  	struct fetch_pack_args args;
  	struct ref *refs_tmp = NULL;
@@@ -239,21 -252,29 +262,32 @@@
  		data->options.check_self_contained_and_connected;
  	args.cloning = transport->cloning;
  	args.update_shallow = data->options.update_shallow;
 +	args.from_promisor = data->options.from_promisor;
 +	args.no_dependents = data->options.no_dependents;
 +	args.filter_options = data->options.filter_options;
+ 	args.stateless_rpc = transport->stateless_rpc;
  
- 	if (!data->got_remote_heads) {
- 		connect_setup(transport, 0);
- 		get_remote_heads(data->fd[0], NULL, 0, &refs_tmp, 0,
- 				 NULL, &data->shallow);
- 		data->got_remote_heads = 1;
+ 	if (!data->got_remote_heads)
+ 		refs_tmp = get_refs_via_connect(transport, 0, NULL);
+ 
+ 	switch (data->version) {
+ 	case protocol_v2:
+ 		refs = fetch_pack(&args, data->fd, data->conn,
+ 				  refs_tmp ? refs_tmp : transport->remote_refs,
+ 				  dest, to_fetch, nr_heads, &data->shallow,
+ 				  &transport->pack_lockfile, data->version);
+ 		break;
+ 	case protocol_v1:
+ 	case protocol_v0:
+ 		refs = fetch_pack(&args, data->fd, data->conn,
+ 				  refs_tmp ? refs_tmp : transport->remote_refs,
+ 				  dest, to_fetch, nr_heads, &data->shallow,
+ 				  &transport->pack_lockfile, data->version);
+ 		break;
+ 	case protocol_unknown_version:
+ 		BUG("unknown protocol version");
  	}
  
- 	refs = fetch_pack(&args, data->fd, data->conn,
- 			  refs_tmp ? refs_tmp : transport->remote_refs,
- 			  dest, to_fetch, nr_heads, &data->shallow,
- 			  &transport->pack_lockfile);
  	close(data->fd[0]);
  	close(data->fd[1]);
  	if (finish_connect(data->conn))
@@@ -368,7 -389,7 +402,7 @@@ static void print_ok_ref_status(struct 
  		char type;
  		const char *msg;
  
 -		strbuf_add_unique_abbrev(&quickref, ref->old_oid.hash,
 +		strbuf_add_unique_abbrev(&quickref, &ref->old_oid,
  					 DEFAULT_ABBREV);
  		if (ref->forced_update) {
  			strbuf_addstr(&quickref, "...");
@@@ -379,7 -400,7 +413,7 @@@
  			type = ' ';
  			msg = NULL;
  		}
 -		strbuf_add_unique_abbrev(&quickref, ref->new_oid.hash,
 +		strbuf_add_unique_abbrev(&quickref, &ref->new_oid,
  					 DEFAULT_ABBREV);
  
  		print_ref_status(type, quickref.buf, ref, ref->peer_ref, msg,
@@@ -462,7 -483,7 +496,7 @@@ static int print_one_push_status(struc
  static int measure_abbrev(const struct object_id *oid, int sofar)
  {
  	char hex[GIT_MAX_HEXSZ + 1];
 -	int w = find_unique_abbrev_r(hex, oid->hash, DEFAULT_ABBREV);
 +	int w = find_unique_abbrev_r(hex, oid, DEFAULT_ABBREV);
  
  	return (w < sofar) ? sofar : w;
  }
@@@ -552,16 -573,10 +586,10 @@@ static int git_transport_push(struct tr
  {
  	struct git_transport_data *data = transport->data;
  	struct send_pack_args args;
- 	int ret;
- 
- 	if (!data->got_remote_heads) {
- 		struct ref *tmp_refs;
- 		connect_setup(transport, 1);
+ 	int ret = 0;
  
- 		get_remote_heads(data->fd[0], NULL, 0, &tmp_refs, REF_NORMAL,
- 				 NULL, &data->shallow);
- 		data->got_remote_heads = 1;
- 	}
+ 	if (!data->got_remote_heads)
+ 		get_refs_via_connect(transport, 1, NULL);
  
  	memset(&args, 0, sizeof(args));
  	args.send_mirror = !!(flags & TRANSPORT_PUSH_MIRROR);
@@@ -583,8 -598,18 +611,18 @@@
  	else
  		args.push_cert = SEND_PACK_PUSH_CERT_NEVER;
  
- 	ret = send_pack(&args, data->fd, data->conn, remote_refs,
- 			&data->extra_have);
+ 	switch (data->version) {
+ 	case protocol_v2:
+ 		die("support for protocol v2 not implemented yet");
+ 		break;
+ 	case protocol_v1:
+ 	case protocol_v0:
+ 		ret = send_pack(&args, data->fd, data->conn, remote_refs,
+ 				&data->extra_have);
+ 		break;
+ 	case protocol_unknown_version:
+ 		BUG("unknown protocol version");
+ 	}
  
  	close(data->fd[1]);
  	close(data->fd[0]);
@@@ -1007,11 -1032,38 +1045,38 @@@ int transport_push(struct transport *tr
  		int porcelain = flags & TRANSPORT_PUSH_PORCELAIN;
  		int pretend = flags & TRANSPORT_PUSH_DRY_RUN;
  		int push_ret, ret, err;
+ 		struct refspec *tmp_rs;
+ 		struct argv_array ref_prefixes = ARGV_ARRAY_INIT;
+ 		int i;
  
  		if (check_push_refs(local_refs, refspec_nr, refspec) < 0)
  			return -1;
  
- 		remote_refs = transport->vtable->get_refs_list(transport, 1);
+ 		tmp_rs = parse_push_refspec(refspec_nr, refspec);
+ 		for (i = 0; i < refspec_nr; i++) {
+ 			const char *prefix = NULL;
+ 
+ 			if (tmp_rs[i].dst)
+ 				prefix = tmp_rs[i].dst;
+ 			else if (tmp_rs[i].src && !tmp_rs[i].exact_sha1)
+ 				prefix = tmp_rs[i].src;
+ 
+ 			if (prefix) {
+ 				const char *glob = strchr(prefix, '*');
+ 				if (glob)
+ 					argv_array_pushf(&ref_prefixes, "%.*s",
+ 							 (int)(glob - prefix),
+ 							 prefix);
+ 				else
+ 					expand_ref_prefix(&ref_prefixes, prefix);
+ 			}
+ 		}
+ 
+ 		remote_refs = transport->vtable->get_refs_list(transport, 1,
+ 							       &ref_prefixes);
+ 
+ 		argv_array_clear(&ref_prefixes);
+ 		free_refspec(refspec_nr, tmp_rs);
  
  		if (flags & TRANSPORT_PUSH_ALL)
  			match_flags |= MATCH_REFS_ALL;
@@@ -1117,10 -1169,13 +1182,13 @@@
  	return 1;
  }
  
- const struct ref *transport_get_remote_refs(struct transport *transport)
+ const struct ref *transport_get_remote_refs(struct transport *transport,
+ 					    const struct argv_array *ref_prefixes)
  {
  	if (!transport->got_remote_refs) {
- 		transport->remote_refs = transport->vtable->get_refs_list(transport, 0);
+ 		transport->remote_refs =
+ 			transport->vtable->get_refs_list(transport, 0,
+ 							 ref_prefixes);
  		transport->got_remote_refs = 1;
  	}
  
diff --combined transport.h
index 3c68d73b21,0e602d4d47..e783cfa075
--- a/transport.h
+++ b/transport.h
@@@ -4,7 -4,6 +4,7 @@@
  #include "cache.h"
  #include "run-command.h"
  #include "remote.h"
 +#include "list-objects-filter-options.h"
  
  struct string_list;
  
@@@ -16,15 -15,12 +16,15 @@@ struct git_transport_options 
  	unsigned self_contained_and_connected : 1;
  	unsigned update_shallow : 1;
  	unsigned deepen_relative : 1;
 +	unsigned from_promisor : 1;
 +	unsigned no_dependents : 1;
  	int depth;
  	const char *deepen_since;
  	const struct string_list *deepen_not;
  	const char *uploadpack;
  	const char *receivepack;
  	struct push_cas_option *cas;
 +	struct list_objects_filter_options filter_options;
  };
  
  enum transport_family {
@@@ -59,6 -55,12 +59,12 @@@ struct transport 
  	 */
  	unsigned cloning : 1;
  
+ 	/*
+ 	 * Indicates that the transport is connected via a half-duplex
+ 	 * connection and should operate in stateless-rpc mode.
+ 	 */
+ 	unsigned stateless_rpc : 1;
+ 
  	/*
  	 * These strings will be passed to the {pre, post}-receive hook,
  	 * on the remote side, if both sides support the push options capability.
@@@ -163,18 -165,6 +169,18 @@@ void transport_check_allowed(const cha
  /* Send push certificates */
  #define TRANS_OPT_PUSH_CERT "pushcert"
  
 +/* Indicate that these objects are being fetched by a promisor */
 +#define TRANS_OPT_FROM_PROMISOR "from-promisor"
 +
 +/*
 + * Indicate that only the objects wanted need to be fetched, not their
 + * dependents
 + */
 +#define TRANS_OPT_NO_DEPENDENTS "no-dependents"
 +
 +/* Filter objects for partial clone and fetch */
 +#define TRANS_OPT_LIST_OBJECTS_FILTER "filter"
 +
  /**
   * Returns 0 if the option was used, non-zero otherwise. Prints a
   * message to stderr if the option is not used.
@@@ -194,7 -184,17 +200,17 @@@ int transport_push(struct transport *co
  		   int refspec_nr, const char **refspec, int flags,
  		   unsigned int * reject_reasons);
  
- const struct ref *transport_get_remote_refs(struct transport *transport);
+ /*
+  * Retrieve refs from a remote.
+  *
+  * Optionally a list of ref prefixes can be provided which can be sent to the
+  * server (when communicating using protocol v2) to enable it to limit the ref
+  * advertisement.  Since ref filtering is done on the server's end (and only
+  * when using protocol v2), this can return refs which don't match the provided
+  * ref_prefixes.
+  */
+ const struct ref *transport_get_remote_refs(struct transport *transport,
+ 					    const struct argv_array *ref_prefixes);
  
  int transport_fetch_refs(struct transport *transport, struct ref *refs);
  void transport_unlock_pack(struct transport *transport);
diff --combined upload-pack.c
index 4a82602be5,4c9428c2db..87b4d32a6e
--- a/upload-pack.c
+++ b/upload-pack.c
@@@ -6,27 -6,19 +6,22 @@@
  #include "tag.h"
  #include "object.h"
  #include "commit.h"
- #include "exec_cmd.h"
  #include "diff.h"
  #include "revision.h"
  #include "list-objects.h"
 +#include "list-objects-filter.h"
 +#include "list-objects-filter-options.h"
  #include "run-command.h"
  #include "connect.h"
  #include "sigchain.h"
  #include "version.h"
  #include "string-list.h"
- #include "parse-options.h"
  #include "argv-array.h"
  #include "prio-queue.h"
  #include "protocol.h"
 +#include "quote.h"
- 
- static const char * const upload_pack_usage[] = {
- 	N_("git upload-pack [<options>] <dir>"),
- 	NULL
- };
+ #include "upload-pack.h"
+ #include "serve.h"
  
  /* Remember to update object flag allocation in object.h */
  #define THEY_HAVE	(1u << 11)
@@@ -64,14 -56,9 +59,13 @@@ static int keepalive = 5
   * otherwise maximum packet size (up to 65520 bytes).
   */
  static int use_sideband;
- static int advertise_refs;
  static int stateless_rpc;
  static const char *pack_objects_hook;
  
 +static int filter_capability_requested;
 +static int allow_filter;
 +static struct list_objects_filter_options filter_options;
 +
  static void reset_timeout(void)
  {
  	alarm(timeout);
@@@ -139,17 -126,6 +133,17 @@@ static void create_pack_file(void
  		argv_array_push(&pack_objects.args, "--delta-base-offset");
  	if (use_include_tag)
  		argv_array_push(&pack_objects.args, "--include-tag");
 +	if (filter_options.filter_spec) {
 +		if (pack_objects.use_shell) {
 +			struct strbuf buf = STRBUF_INIT;
 +			sq_quote_buf(&buf, filter_options.filter_spec);
 +			argv_array_pushf(&pack_objects.args, "--filter=%s", buf.buf);
 +			strbuf_release(&buf);
 +		} else {
 +			argv_array_pushf(&pack_objects.args, "--filter=%s",
 +					 filter_options.filter_spec);
 +		}
 +	}
  
  	pack_objects.in = -1;
  	pack_objects.out = -1;
@@@ -734,7 -710,6 +728,6 @@@ static void deepen(int depth, int deepe
  	}
  
  	send_unshallow(shallows);
- 	packet_flush(1);
  }
  
  static void deepen_by_rev_list(int ac, const char **av,
@@@ -746,7 -721,122 +739,122 @@@
  	send_shallow(result);
  	free_commit_list(result);
  	send_unshallow(shallows);
- 	packet_flush(1);
+ }
+ 
+ /* Returns 1 if a shallow list is sent or 0 otherwise */
+ static int send_shallow_list(int depth, int deepen_rev_list,
+ 			     timestamp_t deepen_since,
+ 			     struct string_list *deepen_not,
+ 			     struct object_array *shallows)
+ {
+ 	int ret = 0;
+ 
+ 	if (depth > 0 && deepen_rev_list)
+ 		die("git upload-pack: deepen and deepen-since (or deepen-not) cannot be used together");
+ 	if (depth > 0) {
+ 		deepen(depth, deepen_relative, shallows);
+ 		ret = 1;
+ 	} else if (deepen_rev_list) {
+ 		struct argv_array av = ARGV_ARRAY_INIT;
+ 		int i;
+ 
+ 		argv_array_push(&av, "rev-list");
+ 		if (deepen_since)
+ 			argv_array_pushf(&av, "--max-age=%"PRItime, deepen_since);
+ 		if (deepen_not->nr) {
+ 			argv_array_push(&av, "--not");
+ 			for (i = 0; i < deepen_not->nr; i++) {
+ 				struct string_list_item *s = deepen_not->items + i;
+ 				argv_array_push(&av, s->string);
+ 			}
+ 			argv_array_push(&av, "--not");
+ 		}
+ 		for (i = 0; i < want_obj.nr; i++) {
+ 			struct object *o = want_obj.objects[i].item;
+ 			argv_array_push(&av, oid_to_hex(&o->oid));
+ 		}
+ 		deepen_by_rev_list(av.argc, av.argv, shallows);
+ 		argv_array_clear(&av);
+ 		ret = 1;
+ 	} else {
+ 		if (shallows->nr > 0) {
+ 			int i;
+ 			for (i = 0; i < shallows->nr; i++)
+ 				register_shallow(&shallows->objects[i].item->oid);
+ 		}
+ 	}
+ 
+ 	shallow_nr += shallows->nr;
+ 	return ret;
+ }
+ 
+ static int process_shallow(const char *line, struct object_array *shallows)
+ {
+ 	const char *arg;
+ 	if (skip_prefix(line, "shallow ", &arg)) {
+ 		struct object_id oid;
+ 		struct object *object;
+ 		if (get_oid_hex(arg, &oid))
+ 			die("invalid shallow line: %s", line);
+ 		object = parse_object(&oid);
+ 		if (!object)
+ 			return 1;
+ 		if (object->type != OBJ_COMMIT)
+ 			die("invalid shallow object %s", oid_to_hex(&oid));
+ 		if (!(object->flags & CLIENT_SHALLOW)) {
+ 			object->flags |= CLIENT_SHALLOW;
+ 			add_object_array(object, NULL, shallows);
+ 		}
+ 		return 1;
+ 	}
+ 
+ 	return 0;
+ }
+ 
+ static int process_deepen(const char *line, int *depth)
+ {
+ 	const char *arg;
+ 	if (skip_prefix(line, "deepen ", &arg)) {
+ 		char *end = NULL;
+ 		*depth = (int)strtol(arg, &end, 0);
+ 		if (!end || *end || *depth <= 0)
+ 			die("Invalid deepen: %s", line);
+ 		return 1;
+ 	}
+ 
+ 	return 0;
+ }
+ 
+ static int process_deepen_since(const char *line, timestamp_t *deepen_since, int *deepen_rev_list)
+ {
+ 	const char *arg;
+ 	if (skip_prefix(line, "deepen-since ", &arg)) {
+ 		char *end = NULL;
+ 		*deepen_since = parse_timestamp(arg, &end, 0);
+ 		if (!end || *end || !deepen_since ||
+ 		    /* revisions.c's max_age -1 is special */
+ 		    *deepen_since == -1)
+ 			die("Invalid deepen-since: %s", line);
+ 		*deepen_rev_list = 1;
+ 		return 1;
+ 	}
+ 	return 0;
+ }
+ 
+ static int process_deepen_not(const char *line, struct string_list *deepen_not, int *deepen_rev_list)
+ {
+ 	const char *arg;
+ 	if (skip_prefix(line, "deepen-not ", &arg)) {
+ 		char *ref = NULL;
+ 		struct object_id oid;
+ 		if (expand_ref(arg, strlen(arg), &oid, &ref) != 1)
+ 			die("git upload-pack: ambiguous deepen-not: %s", line);
+ 		string_list_append(deepen_not, ref);
+ 		free(ref);
+ 		*deepen_rev_list = 1;
+ 		return 1;
+ 	}
+ 	return 0;
  }
  
  static void receive_needs(void)
@@@ -770,55 -860,15 +878,22 @@@
  		if (!line)
  			break;
  
- 		if (skip_prefix(line, "shallow ", &arg)) {
- 			struct object_id oid;
- 			struct object *object;
- 			if (get_oid_hex(arg, &oid))
- 				die("invalid shallow line: %s", line);
- 			object = parse_object(&oid);
- 			if (!object)
- 				continue;
- 			if (object->type != OBJ_COMMIT)
- 				die("invalid shallow object %s", oid_to_hex(&oid));
- 			if (!(object->flags & CLIENT_SHALLOW)) {
- 				object->flags |= CLIENT_SHALLOW;
- 				add_object_array(object, NULL, &shallows);
- 			}
+ 		if (process_shallow(line, &shallows))
  			continue;
- 		}
- 		if (skip_prefix(line, "deepen ", &arg)) {
- 			char *end = NULL;
- 			depth = strtol(arg, &end, 0);
- 			if (!end || *end || depth <= 0)
- 				die("Invalid deepen: %s", line);
+ 		if (process_deepen(line, &depth))
  			continue;
- 		}
- 		if (skip_prefix(line, "deepen-since ", &arg)) {
- 			char *end = NULL;
- 			deepen_since = parse_timestamp(arg, &end, 0);
- 			if (!end || *end || !deepen_since ||
- 			    /* revisions.c's max_age -1 is special */
- 			    deepen_since == -1)
- 				die("Invalid deepen-since: %s", line);
- 			deepen_rev_list = 1;
+ 		if (process_deepen_since(line, &deepen_since, &deepen_rev_list))
  			continue;
- 		}
- 		if (skip_prefix(line, "deepen-not ", &arg)) {
- 			char *ref = NULL;
- 			struct object_id oid;
- 			if (expand_ref(arg, strlen(arg), &oid, &ref) != 1)
- 				die("git upload-pack: ambiguous deepen-not: %s", line);
- 			string_list_append(&deepen_not, ref);
- 			free(ref);
- 			deepen_rev_list = 1;
+ 		if (process_deepen_not(line, &deepen_not, &deepen_rev_list))
  			continue;
- 		}
+ 
 +		if (skip_prefix(line, "filter ", &arg)) {
 +			if (!filter_capability_requested)
 +				die("git upload-pack: filtering capability not negotiated");
 +			parse_list_objects_filter(&filter_options, arg);
 +			continue;
 +		}
++
  		if (!skip_prefix(line, "want ", &arg) ||
  		    get_oid_hex(arg, &oid_buf))
  			die("git upload-pack: protocol error, "
@@@ -846,8 -896,6 +921,8 @@@
  			no_progress = 1;
  		if (parse_feature_request(features, "include-tag"))
  			use_include_tag = 1;
 +		if (allow_filter && parse_feature_request(features, "filter"))
 +			filter_capability_requested = 1;
  
  		o = parse_object(&oid_buf);
  		if (!o) {
@@@ -881,40 -929,10 +956,10 @@@
  
  	if (depth == 0 && !deepen_rev_list && shallows.nr == 0)
  		return;
- 	if (depth > 0 && deepen_rev_list)
- 		die("git upload-pack: deepen and deepen-since (or deepen-not) cannot be used together");
- 	if (depth > 0)
- 		deepen(depth, deepen_relative, &shallows);
- 	else if (deepen_rev_list) {
- 		struct argv_array av = ARGV_ARRAY_INIT;
- 		int i;
  
- 		argv_array_push(&av, "rev-list");
- 		if (deepen_since)
- 			argv_array_pushf(&av, "--max-age=%"PRItime, deepen_since);
- 		if (deepen_not.nr) {
- 			argv_array_push(&av, "--not");
- 			for (i = 0; i < deepen_not.nr; i++) {
- 				struct string_list_item *s = deepen_not.items + i;
- 				argv_array_push(&av, s->string);
- 			}
- 			argv_array_push(&av, "--not");
- 		}
- 		for (i = 0; i < want_obj.nr; i++) {
- 			struct object *o = want_obj.objects[i].item;
- 			argv_array_push(&av, oid_to_hex(&o->oid));
- 		}
- 		deepen_by_rev_list(av.argc, av.argv, &shallows);
- 		argv_array_clear(&av);
- 	}
- 	else
- 		if (shallows.nr > 0) {
- 			int i;
- 			for (i = 0; i < shallows.nr; i++)
- 				register_shallow(&shallows.objects[i].item->oid);
- 		}
- 
- 	shallow_nr += shallows.nr;
+ 	if (send_shallow_list(depth, deepen_rev_list, deepen_since,
+ 			      &deepen_not, &shallows))
+ 		packet_flush(1);
  	object_array_clear(&shallows);
  }
  
@@@ -967,7 -985,7 +1012,7 @@@ static int send_ref(const char *refname
  		struct strbuf symref_info = STRBUF_INIT;
  
  		format_symref_info(&symref_info, cb_data);
 -		packet_write_fmt(1, "%s %s%c%s%s%s%s%s agent=%s\n",
 +		packet_write_fmt(1, "%s %s%c%s%s%s%s%s%s agent=%s\n",
  			     oid_to_hex(oid), refname_nons,
  			     0, capabilities,
  			     (allow_unadvertised_object_request & ALLOW_TIP_SHA1) ?
@@@ -976,7 -994,6 +1021,7 @@@
  				     " allow-reachable-sha1-in-want" : "",
  			     stateless_rpc ? " no-done" : "",
  			     symref_info.buf,
 +			     allow_filter ? " filter" : "",
  			     git_user_agent_sanitized());
  		strbuf_release(&symref_info);
  	} else {
@@@ -1004,33 -1021,6 +1049,6 @@@ static int find_symref(const char *refn
  	return 0;
  }
  
- static void upload_pack(void)
- {
- 	struct string_list symref = STRING_LIST_INIT_DUP;
- 
- 	head_ref_namespaced(find_symref, &symref);
- 
- 	if (advertise_refs || !stateless_rpc) {
- 		reset_timeout();
- 		head_ref_namespaced(send_ref, &symref);
- 		for_each_namespaced_ref(send_ref, &symref);
- 		advertise_shallow_grafts(1);
- 		packet_flush(1);
- 	} else {
- 		head_ref_namespaced(check_ref, NULL);
- 		for_each_namespaced_ref(check_ref, NULL);
- 	}
- 	string_list_clear(&symref, 1);
- 	if (advertise_refs)
- 		return;
- 
- 	receive_needs();
- 	if (want_obj.nr) {
- 		get_common_commits();
- 		create_pack_file();
- 	}
- }
- 
  static int upload_pack_config(const char *var, const char *value, void *unused)
  {
  	if (!strcmp("uploadpack.allowtipsha1inwant", var)) {
@@@ -1055,64 -1045,360 +1073,362 @@@
  	} else if (current_config_scope() != CONFIG_SCOPE_REPO) {
  		if (!strcmp("uploadpack.packobjectshook", var))
  			return git_config_string(&pack_objects_hook, var, value);
 +	} else if (!strcmp("uploadpack.allowfilter", var)) {
 +		allow_filter = git_config_bool(var, value);
  	}
  	return parse_hide_refs_config(var, value, "uploadpack");
  }
  
- int cmd_main(int argc, const char **argv)
+ void upload_pack(struct upload_pack_options *options)
  {
- 	const char *dir;
- 	int strict = 0;
- 	struct option options[] = {
- 		OPT_BOOL(0, "stateless-rpc", &stateless_rpc,
- 			 N_("quit after a single request/response exchange")),
- 		OPT_BOOL(0, "advertise-refs", &advertise_refs,
- 			 N_("exit immediately after initial ref advertisement")),
- 		OPT_BOOL(0, "strict", &strict,
- 			 N_("do not try <directory>/.git/ if <directory> is no Git directory")),
- 		OPT_INTEGER(0, "timeout", &timeout,
- 			    N_("interrupt transfer after <n> seconds of inactivity")),
- 		OPT_END()
- 	};
+ 	struct string_list symref = STRING_LIST_INIT_DUP;
  
- 	packet_trace_identity("upload-pack");
- 	check_replace_refs = 0;
+ 	stateless_rpc = options->stateless_rpc;
+ 	timeout = options->timeout;
+ 	daemon_mode = options->daemon_mode;
  
- 	argc = parse_options(argc, argv, NULL, options, upload_pack_usage, 0);
+ 	git_config(upload_pack_config, NULL);
  
- 	if (argc != 1)
- 		usage_with_options(upload_pack_usage, options);
+ 	head_ref_namespaced(find_symref, &symref);
  
- 	if (timeout)
- 		daemon_mode = 1;
+ 	if (options->advertise_refs || !stateless_rpc) {
+ 		reset_timeout();
+ 		head_ref_namespaced(send_ref, &symref);
+ 		for_each_namespaced_ref(send_ref, &symref);
+ 		advertise_shallow_grafts(1);
+ 		packet_flush(1);
+ 	} else {
+ 		head_ref_namespaced(check_ref, NULL);
+ 		for_each_namespaced_ref(check_ref, NULL);
+ 	}
+ 	string_list_clear(&symref, 1);
+ 	if (options->advertise_refs)
+ 		return;
  
- 	setup_path();
+ 	receive_needs();
+ 	if (want_obj.nr) {
+ 		get_common_commits();
+ 		create_pack_file();
+ 	}
+ }
  
- 	dir = argv[0];
+ struct upload_pack_data {
+ 	struct object_array wants;
+ 	struct oid_array haves;
  
- 	if (!enter_repo(dir, strict))
- 		die("'%s' does not appear to be a git repository", dir);
+ 	struct object_array shallows;
+ 	struct string_list deepen_not;
+ 	int depth;
+ 	timestamp_t deepen_since;
+ 	int deepen_rev_list;
+ 	int deepen_relative;
  
- 	git_config(upload_pack_config, NULL);
+ 	unsigned stateless_rpc : 1;
  
- 	switch (determine_protocol_version_server()) {
- 	case protocol_v1:
- 		/*
- 		 * v1 is just the original protocol with a version string,
- 		 * so just fall through after writing the version string.
- 		 */
- 		if (advertise_refs || !stateless_rpc)
- 			packet_write_fmt(1, "version 1\n");
- 
- 		/* fallthrough */
- 	case protocol_v0:
- 		upload_pack();
- 		break;
- 	case protocol_unknown_version:
- 		BUG("unknown protocol version");
+ 	unsigned use_thin_pack : 1;
+ 	unsigned use_ofs_delta : 1;
+ 	unsigned no_progress : 1;
+ 	unsigned use_include_tag : 1;
+ 	unsigned done : 1;
+ };
+ 
+ static void upload_pack_data_init(struct upload_pack_data *data)
+ {
+ 	struct object_array wants = OBJECT_ARRAY_INIT;
+ 	struct oid_array haves = OID_ARRAY_INIT;
+ 	struct object_array shallows = OBJECT_ARRAY_INIT;
+ 	struct string_list deepen_not = STRING_LIST_INIT_DUP;
+ 
+ 	memset(data, 0, sizeof(*data));
+ 	data->wants = wants;
+ 	data->haves = haves;
+ 	data->shallows = shallows;
+ 	data->deepen_not = deepen_not;
+ }
+ 
+ static void upload_pack_data_clear(struct upload_pack_data *data)
+ {
+ 	object_array_clear(&data->wants);
+ 	oid_array_clear(&data->haves);
+ 	object_array_clear(&data->shallows);
+ 	string_list_clear(&data->deepen_not, 0);
+ }
+ 
+ static int parse_want(const char *line)
+ {
+ 	const char *arg;
+ 	if (skip_prefix(line, "want ", &arg)) {
+ 		struct object_id oid;
+ 		struct object *o;
+ 
+ 		if (get_oid_hex(arg, &oid))
+ 			die("git upload-pack: protocol error, "
+ 			    "expected to get oid, not '%s'", line);
+ 
+ 		o = parse_object(&oid);
+ 		if (!o) {
+ 			packet_write_fmt(1,
+ 					 "ERR upload-pack: not our ref %s",
+ 					 oid_to_hex(&oid));
+ 			die("git upload-pack: not our ref %s",
+ 			    oid_to_hex(&oid));
+ 		}
+ 
+ 		if (!(o->flags & WANTED)) {
+ 			o->flags |= WANTED;
+ 			add_object_array(o, NULL, &want_obj);
+ 		}
+ 
+ 		return 1;
+ 	}
+ 
+ 	return 0;
+ }
+ 
+ static int parse_have(const char *line, struct oid_array *haves)
+ {
+ 	const char *arg;
+ 	if (skip_prefix(line, "have ", &arg)) {
+ 		struct object_id oid;
+ 
+ 		if (get_oid_hex(arg, &oid))
+ 			die("git upload-pack: expected SHA1 object, got '%s'", arg);
+ 		oid_array_append(haves, &oid);
+ 		return 1;
  	}
  
  	return 0;
  }
+ 
+ static void process_args(struct packet_reader *request,
+ 			 struct upload_pack_data *data)
+ {
+ 	while (packet_reader_read(request) != PACKET_READ_FLUSH) {
+ 		const char *arg = request->line;
+ 
+ 		/* process want */
+ 		if (parse_want(arg))
+ 			continue;
+ 		/* process have line */
+ 		if (parse_have(arg, &data->haves))
+ 			continue;
+ 
+ 		/* process args like thin-pack */
+ 		if (!strcmp(arg, "thin-pack")) {
+ 			use_thin_pack = 1;
+ 			continue;
+ 		}
+ 		if (!strcmp(arg, "ofs-delta")) {
+ 			use_ofs_delta = 1;
+ 			continue;
+ 		}
+ 		if (!strcmp(arg, "no-progress")) {
+ 			no_progress = 1;
+ 			continue;
+ 		}
+ 		if (!strcmp(arg, "include-tag")) {
+ 			use_include_tag = 1;
+ 			continue;
+ 		}
+ 		if (!strcmp(arg, "done")) {
+ 			data->done = 1;
+ 			continue;
+ 		}
+ 
+ 		/* Shallow related arguments */
+ 		if (process_shallow(arg, &data->shallows))
+ 			continue;
+ 		if (process_deepen(arg, &data->depth))
+ 			continue;
+ 		if (process_deepen_since(arg, &data->deepen_since,
+ 					 &data->deepen_rev_list))
+ 			continue;
+ 		if (process_deepen_not(arg, &data->deepen_not,
+ 				       &data->deepen_rev_list))
+ 			continue;
+ 		if (!strcmp(arg, "deepen-relative")) {
+ 			data->deepen_relative = 1;
+ 			continue;
+ 		}
+ 
+ 		/* ignore unknown lines maybe? */
+ 		die("unexpect line: '%s'", arg);
+ 	}
+ }
+ 
+ static int process_haves(struct oid_array *haves, struct oid_array *common)
+ {
+ 	int i;
+ 
+ 	/* Process haves */
+ 	for (i = 0; i < haves->nr; i++) {
+ 		const struct object_id *oid = &haves->oid[i];
+ 		struct object *o;
+ 		int we_knew_they_have = 0;
+ 
+ 		if (!has_object_file(oid))
+ 			continue;
+ 
+ 		oid_array_append(common, oid);
+ 
+ 		o = parse_object(oid);
+ 		if (!o)
+ 			die("oops (%s)", oid_to_hex(oid));
+ 		if (o->type == OBJ_COMMIT) {
+ 			struct commit_list *parents;
+ 			struct commit *commit = (struct commit *)o;
+ 			if (o->flags & THEY_HAVE)
+ 				we_knew_they_have = 1;
+ 			else
+ 				o->flags |= THEY_HAVE;
+ 			if (!oldest_have || (commit->date < oldest_have))
+ 				oldest_have = commit->date;
+ 			for (parents = commit->parents;
+ 			     parents;
+ 			     parents = parents->next)
+ 				parents->item->object.flags |= THEY_HAVE;
+ 		}
+ 		if (!we_knew_they_have)
+ 			add_object_array(o, NULL, &have_obj);
+ 	}
+ 
+ 	return 0;
+ }
+ 
+ static int send_acks(struct oid_array *acks, struct strbuf *response)
+ {
+ 	int i;
+ 
+ 	packet_buf_write(response, "acknowledgments\n");
+ 
+ 	/* Send Acks */
+ 	if (!acks->nr)
+ 		packet_buf_write(response, "NAK\n");
+ 
+ 	for (i = 0; i < acks->nr; i++) {
+ 		packet_buf_write(response, "ACK %s\n",
+ 				 oid_to_hex(&acks->oid[i]));
+ 	}
+ 
+ 	if (ok_to_give_up()) {
+ 		/* Send Ready */
+ 		packet_buf_write(response, "ready\n");
+ 		return 1;
+ 	}
+ 
+ 	return 0;
+ }
+ 
+ static int process_haves_and_send_acks(struct upload_pack_data *data)
+ {
+ 	struct oid_array common = OID_ARRAY_INIT;
+ 	struct strbuf response = STRBUF_INIT;
+ 	int ret = 0;
+ 
+ 	process_haves(&data->haves, &common);
+ 	if (data->done) {
+ 		ret = 1;
+ 	} else if (send_acks(&common, &response)) {
+ 		packet_buf_delim(&response);
+ 		ret = 1;
+ 	} else {
+ 		/* Add Flush */
+ 		packet_buf_flush(&response);
+ 		ret = 0;
+ 	}
+ 
+ 	/* Send response */
+ 	write_or_die(1, response.buf, response.len);
+ 	strbuf_release(&response);
+ 
+ 	oid_array_clear(&data->haves);
+ 	oid_array_clear(&common);
+ 	return ret;
+ }
+ 
+ static void send_shallow_info(struct upload_pack_data *data)
+ {
+ 	/* No shallow info needs to be sent */
+ 	if (!data->depth && !data->deepen_rev_list && !data->shallows.nr &&
+ 	    !is_repository_shallow())
+ 		return;
+ 
+ 	packet_write_fmt(1, "shallow-info\n");
+ 
+ 	if (!send_shallow_list(data->depth, data->deepen_rev_list,
+ 			       data->deepen_since, &data->deepen_not,
+ 			       &data->shallows) && is_repository_shallow())
+ 		deepen(INFINITE_DEPTH, data->deepen_relative, &data->shallows);
+ 
+ 	packet_delim(1);
+ }
+ 
+ enum fetch_state {
+ 	FETCH_PROCESS_ARGS = 0,
+ 	FETCH_SEND_ACKS,
+ 	FETCH_SEND_PACK,
+ 	FETCH_DONE,
+ };
+ 
+ int upload_pack_v2(struct repository *r, struct argv_array *keys,
+ 		   struct packet_reader *request)
+ {
+ 	enum fetch_state state = FETCH_PROCESS_ARGS;
+ 	struct upload_pack_data data;
+ 
+ 	upload_pack_data_init(&data);
+ 	use_sideband = LARGE_PACKET_MAX;
+ 
+ 	while (state != FETCH_DONE) {
+ 		switch (state) {
+ 		case FETCH_PROCESS_ARGS:
+ 			process_args(request, &data);
+ 
+ 			if (!want_obj.nr) {
+ 				/*
+ 				 * Request didn't contain any 'want' lines,
+ 				 * guess they didn't want anything.
+ 				 */
+ 				state = FETCH_DONE;
+ 			} else if (data.haves.nr) {
+ 				/*
+ 				 * Request had 'have' lines, so lets ACK them.
+ 				 */
+ 				state = FETCH_SEND_ACKS;
+ 			} else {
+ 				/*
+ 				 * Request had 'want's but no 'have's so we can
+ 				 * immedietly go to construct and send a pack.
+ 				 */
+ 				state = FETCH_SEND_PACK;
+ 			}
+ 			break;
+ 		case FETCH_SEND_ACKS:
+ 			if (process_haves_and_send_acks(&data))
+ 				state = FETCH_SEND_PACK;
+ 			else
+ 				state = FETCH_DONE;
+ 			break;
+ 		case FETCH_SEND_PACK:
+ 			send_shallow_info(&data);
+ 
+ 			packet_write_fmt(1, "packfile\n");
+ 			create_pack_file();
+ 			state = FETCH_DONE;
+ 			break;
+ 		case FETCH_DONE:
+ 			continue;
+ 		}
+ 	}
+ 
+ 	upload_pack_data_clear(&data);
+ 	return 0;
+ }
+ 
+ int upload_pack_advertise(struct repository *r,
+ 			  struct strbuf *value)
+ {
+ 	if (value)
+ 		strbuf_addstr(value, "shallow");
+ 	return 1;
+ }