upload-pack, receive-pack: introduce protocol version 1
Teach upload-pack and receive-pack to understand and respond using
protocol version 1, if requested.
Protocol version 1 is simply the original and current protocol (what I'm
calling version 0) with the addition of a single packet line, which
precedes the ref advertisement, indicating the protocol version being
spoken.
Signed-off-by: Brandon Williams <bmwill@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
A normal request to git-daemon is structured as
"command path/to/repo\0host=..\0" and due to a bug introduced in 49ba83fb6 (Add virtualization support to git-daemon, 2006-09-19) we
aren't able to place any extra arguments (separated by NULs) besides the
host otherwise the parsing of those arguments would enter an infinite
loop. This bug was fixed in 73bb33a94 (daemon: Strictly parse the
"extra arg" part of the command, 2009-06-04) but a check was put in
place to disallow extra arguments so that new clients wouldn't trigger
this bug in older servers.
In order to get around this limitation teach git-daemon to recognize
additional request arguments hidden behind a second NUL byte. Requests
can then be structured like:
"command path/to/repo\0host=..\0\0version=1\0key=value\0". git-daemon
can then parse out the extra arguments and set 'GIT_PROTOCOL'
accordingly.
By placing these extra arguments behind a second NUL byte we can skirt
around both the infinite loop bug in 49ba83fb6 (Add virtualization
support to git-daemon, 2006-09-19) as well as the explicit disallowing
of extra arguments introduced in 73bb33a94 (daemon: Strictly parse the
"extra arg" part of the command, 2009-06-04) because both of these
versions of git-daemon check for a single NUL byte after the host
argument before terminating the argument parsing.
Signed-off-by: Brandon Williams <bmwill@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Create protocol.{c,h} and provide functions which future servers and
clients can use to determine which protocol to use or is being used.
Also introduce the 'GIT_PROTOCOL' environment variable which will be
used to communicate a colon separated list of keys with optional values
to a server. Unknown keys and values must be tolerated. This mechanism
is used to communicate which version of the wire protocol a client would
like to use with a server.
Signed-off-by: Brandon Williams <bmwill@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add a function which can be used to write the contents of an arbitrary
buffer. This makes it easy to build up data in a buffer before writing
the packet instead of formatting the entire contents of the packet using
'packet_write_fmt()'.
Signed-off-by: Brandon Williams <bmwill@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Currently, get_remote_heads() parses the ref advertisement in one loop,
allowing refs and shallow lines to intersperse, despite this not being
allowed by the specification. Refactor get_remote_heads() to use two
loops instead, enforcing that refs come first, and then shallows.
This also makes it easier to teach get_remote_heads() to interpret other
lines in the ref advertisement, which will be done in a subsequent
patch.
As part of this change, this patch interprets capabilities only on the
first line in the ref advertisement, printing a warning message when
encountering capabilities on other lines.
Signed-off-by: Jonathan Tan <jonathantanmy@google.com> Signed-off-by: Brandon Williams <bmwill@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* maint:
Git 2.14.2
Git 2.13.6
Git 2.12.5
Git 2.11.4
Git 2.10.5
cvsimport: shell-quote variable used in backticks
archimport: use safe_pipe_capture for user input
shell: drop git-cvsserver support by default
cvsserver: use safe_pipe_capture for `constant commands` as well
cvsserver: use safe_pipe_capture instead of backticks
cvsserver: move safe_pipe_capture() to the main package
On Cygwin, "ulimit -s" does not report failure but it does not work
at all, which causes an unexpected success of some tests that
expect failures under a limited stack situation. This has been
fixed.
* rj/test-ulimit-on-windows:
t9010-*.sh: skip all tests if the PIPE prereq is missing
test-lib: use more compact expression in PIPE prerequisite
test-lib: don't use ulimit in test prerequisites on cygwin
* jk/revision-remove-cmdline-pathspec:
pathspec doc: parse_pathspec does not maintain references to args
revision: replace "struct cmdline_pathspec" with argv_array
The scripts to drive TravisCI has been reorganized and then an
optimization to avoid spending cycles on a branch whose tip is
tagged has been implemented.
* ls/travis-scriptify:
travis-ci: fix "skip_branch_tip_with_tag()" string comparison
travis: dedent a few scripts that are indented overly deeply
travis-ci: skip a branch build if equal tag is present
travis-ci: move Travis CI code into dedicated scripts
"git gc" tries to avoid running two instances at the same time by
reading and writing pid/host from and to a lock file; it used to
use an incorrect fscanf() format when reading, which has been
corrected.
* aw/gc-lockfile-fscanf-fix:
gc: call fscanf() with %<len>s, not %<len>c, when reading hostname
"git imap-send" has our own implementation of the protocol and also
can use more recent libCurl with the imap protocol support. Update
the latter so that it can use the credential subsystem, and then
make it the default option to use, so that we can eventually
deprecate and remove the former.
* nm/imap-send-with-curl:
imap-send: use curl by default when possible
imap_send: setup_curl: retreive credentials if not set in config file
imap-send: add wrapper to get server credentials if needed
imap-send: return with error if curl failed
Step #0 of a planned & larger series to make the in-core object
store per in-core repository object.
* jn/per-repo-object-store-fixes:
replace-objects: evaluate replacement refs without using the object store
push, fetch: error out for submodule entries not pointing to commits
pack: make packed_git_mru global a value instead of a pointer
Many codepaths did not diagnose write failures correctly when disks
go full, due to their misuse of write_in_full() helper function,
which have been corrected.
* jk/write-in-full-fix:
read_pack_header: handle signed/unsigned comparison in read result
config: flip return value of store_write_*()
notes-merge: use ssize_t for write_in_full() return value
pkt-line: check write_in_full() errors against "< 0"
convert less-trivial versions of "write_in_full() != len"
avoid "write_in_full(fd, buf, len) != len" pattern
get-tar-commit-id: check write_in_full() return against 0
config: avoid "write_in_full(fd, buf, len) < len" pattern
A handful of tests to demonstrates a recursive implementation of
"name-rev" hurts.
* mg/name-rev-tests-with-short-stack:
t6120: test describe and name-rev with deep repos
t6120: clean up state after breaking repo
t6120: test name-rev --all and --stdin
t7004: move limited stack prereq to test-lib
09f5e97 ("travis-ci: skip a branch build if equal tag is present",
2017-09-17) introduced the "skip_branch_tip_with_tag" function with
a broken string comparison. Fix it!
Reported-by: SZEDER Gábor <szeder.dev@gmail.com> Signed-off-by: Lars Schneider <larsxschneider@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
pathspec doc: parse_pathspec does not maintain references to args
The command line arguments passed to main() are valid for the life of
a program, but the same is not true for all other argv-style arrays
(e.g. when a caller creates an argv_array). Clarify that
parse_pathspec does not rely on the argv passed to it to remain valid.
This makes it easier to tell that callers like "git rev-list --stdin"
are safe and ensures that that is more likely to remain true as the
implementation of parse_pathspec evolves.
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Many of our programs consider that it is OK to release dynamic
storage that is used throughout the life of the program by simply
exiting, but this makes it harder to leak detection tools to avoid
reporting false positives. Plug many existing leaks and introduce
a mechanism for developers to mark that the region of memory
pointed by a pointer is not lost/leaking to help these tools.
* jk/leak-checkers:
git-compat-util: make UNLEAK less error-prone
revision: replace "struct cmdline_pathspec" with argv_array
We assemble an array of strings in a custom struct,
NULL-terminate the result, and then pass it to
parse_pathspec().
But then we never free the array or the individual strings
(nor can we do the latter, as they are heap-allocated when
they come from stdin but not when they come from the
passed-in argv).
Let's swap this out for an argv_array. It does the same
thing with fewer lines of code, and it's safe to call
argv_array_clear() at the end to avoid a memory leak.
Reported-by: Martin Ågren <martin.agren@gmail.com> Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Some implementations of `echo` support the '-e' option to enable
backslash interpretation of the following string.
As an addition, they support '-E' to turn it off.
However, none of these are portable, POSIX doesn't even mention them,
and many implementations don't support them.
A check for '-n' is already done in check-non-portable-shell.pl,
extend it to cover '-n', '-e' or '-E'.
Signed-off-by: Torsten Bögershausen <tboegi@web.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Commit 0e5bba5 ("add UNLEAK annotation for reducing leak false
positives", 2017-09-08) introduced an UNLEAK macro to be used as
"UNLEAK(var);", but its existing definitions leave semicolons that act
as empty statements, which will lead to syntax errors, e.g.
if (condition)
UNLEAK(var);
else
something_else(var);
would be broken with two statements between if (condition) and else.
Lose the excess semicolon from the end of the macro replacement text.
Signed-off-by: Jonathan Tan <jonathantanmy@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Even though this probably works almost everywhere, it is undefined
behavior, and it could plausibly cause highly-optimizing compilers to
misbehave. C99 section 6.5.6 paragraph 8 explains:
If both the pointer operand and the result point to elements
of the same array object, or one past the last element of the
array object, the evaluation shall not produce an overflow;
otherwise, the behavior is undefined.
and (6.3.2.3.3) a null pointer does not point to anything.
Guard the loop with a NULL check to make the intent crystal clear to
even the most pedantic compiler. A suitably clever compiler could let
the NULL check only run in the first iteration, but regardless, this
overhead is likely to be dwarfed by the work to be done on each item.
This problem was noticed by Coverity.
[jn: using a NULL check instead of a placeholder empty list;
fleshed out the commit message based on mailing list discussion]
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Jonathan Nieder <jrnieder@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
When we fail to open $GIT_DIR/info/alternates, we silently
assume there are no alternates. This is the right thing to
do for ENOENT, but not for other errors.
A hard error is probably overkill here. If we fail to read
an alternates file then either we'll complete our operation
anyway, or we'll fail to find some needed object. Either
way, a warning is good idea. And we already have a helper
function to handle this pattern; let's just call
warn_on_fopen_error().
Note that technically the errno from strbuf_read_file()
might be from a read() error, not open(). But since read()
would never return ENOENT or ENOTDIR, and since it produces
a generic "unable to access" error, it's suitable for
handling errors from either.
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
This patch fixes a regression in v2.11.1 where we might read
past the end of an mmap'd buffer. It was introduced in cf3c635210.
The link_alt_odb_entries() function has always taken a
ptr/len pair as input. Until cf3c635210 (alternates: accept
double-quoted paths, 2016-12-12), we made a copy of those
bytes in a string. But after that commit, we switched to
parsing the input left-to-right, and we ignore "len"
totally, instead reading until we hit a NUL.
This has mostly gone unnoticed for a few reasons:
1. All but one caller passes a NUL-terminated string, with
"len" pointing to the NUL.
2. The remaining caller, read_info_alternates(), passes in
an mmap'd file. Unless the file is an exact multiple of
the page size, it will generally be followed by NUL
padding to the end of the page, which just works.
The easiest way to demonstrate the problem is to build with:
make SANITIZE=address NO_MMAP=Nope test
Any test which involves $GIT_DIR/info/alternates will fail,
as the mmap emulation (correctly) does not add an extra NUL,
and ASAN complains about reading past the end of the buffer.
One solution would be to teach link_alt_odb_entries() to
respect "len". But it's actually a bit tricky, since we
depend on unquote_c_style() under the hood, and it has no
ptr/len variant.
We could also just make a NUL-terminated copy of the input
bytes and operate on that. But since all but one caller
already is passing a string, instead let's just fix that
caller to provide NUL-terminated input in the first place,
by swapping out mmap for strbuf_read_file().
There's no advantage to using mmap on the alternates file.
It's not expected to be large (and anyway, we're copying its
contents into an in-memory linked list). Nor is using
git_open() buying us anything here, since we don't keep the
descriptor open for a long period of time.
Let's also drop the "len" parameter entirely from
link_alt_odb_entries(), since it's completely ignored. That
will avoid any new callers re-introducing a similar bug.
Reported-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
t9010-*.sh: skip all tests if the PIPE prereq is missing
Every test in this file, except one, is marked with the PIPE prereq.
However, that lone test ('set up svn repo'), only performs some setup
work and checks whether the following test should be executed (by
setting an additional SVNREPO prerequisite). Since the following test
also requires the PIPE prerequisite, performing the setup test, when the
PIPE preequisite is missing, is simply wasted effort. Use the skip-all
test facility to skip all tests when the PIPE prerequisite is missing.
Signed-off-by: Ramsay Jones <ramsay@ramsayjones.plus.com> Reviewed-by: Jonathan Nieder <jrnieder@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
test-lib: use more compact expression in PIPE prerequisite
Signed-off-by: Ramsay Jones <ramsay@ramsayjones.plus.com> Reviewed-by: Jonathan Nieder <jrnieder@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Running `git fetch --unshallow` on a repo that is not in fact shallow
produces a fatal error message. Add a helper to rev-parse that scripters
can use to determine whether a repo is shallow or not.
Signed-off-by: Øystein Walle <oystwa@gmail.com> Reviewed-by: Jonathan Nieder <jrnieder@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Unlike "git commit-tree < file", "git commit-tree -F file" did not
pass the contents of the file verbatim and instead completed an
incomplete line at the end, if exists. The latter has been updated
to match the behaviour of the former.
* rk/commit-tree-make-F-verbatim:
commit-tree: do not complete line in -F input
* rs/strbuf-leakfix: (34 commits)
wt-status: release strbuf after use in wt_longstatus_print_tracking()
wt-status: release strbuf after use in read_rebase_todolist()
vcs-svn: release strbuf after use in end_revision()
utf8: release strbuf on error return in strbuf_utf8_replace()
userdiff: release strbuf after use in userdiff_get_textconv()
transport-helper: release strbuf after use in process_connect_service()
sequencer: release strbuf after use in save_head()
shortlog: release strbuf after use in insert_one_record()
sha1_file: release strbuf on error return in index_path()
send-pack: release strbuf on error return in send_pack()
remote: release strbuf after use in set_url()
remote: release strbuf after use in migrate_file()
remote: release strbuf after use in read_remote_branches()
refs: release strbuf on error return in write_pseudoref()
notes: release strbuf after use in notes_copy_from_stdin()
merge: release strbuf after use in write_merge_heads()
merge: release strbuf after use in save_state()
mailinfo: release strbuf on error return in handle_boundary()
mailinfo: release strbuf after use in handle_from()
help: release strbuf on error return in exec_woman_emacs()
...
Implement transactional update to the packed-ref representation of
references.
* mh/packed-ref-transactions:
files_transaction_finish(): delete reflogs before references
packed-backend: rip out some now-unused code
files_ref_store: use a transaction to update packed refs
t1404: demonstrate two problems with reference transactions
files_initial_transaction_commit(): use a transaction for packed refs
prune_refs(): also free the linked list
files_pack_refs(): use a reference transaction to write packed refs
packed_delete_refs(): implement method
packed_ref_store: implement reference transactions
struct ref_transaction: add a place for backends to store data
packed-backend: don't adjust the reference count on lock/unlock
* kw/merge-recursive-cleanup:
merge-recursive: change current file dir string_lists to hashmap
merge-recursive: remove return value from get_files_dirs
merge-recursive: fix memory leak
As "git commit" to conclude a conflicted "git merge" honors the
commit-msg hook, "git merge" that recoreds a merge commit that
cleanly auto-merges should, but it didn't.
* sb/merge-commit-msg-hook:
builtin/merge: honor commit-msg hook for merges
Many of our programs consider that it is OK to release dynamic
storage that is used throughout the life of the program by simply
exiting, but this makes it harder to leak detection tools to avoid
reporting false positives. Plug many existing leaks and introduce
a mechanism for developers to mark that the region of memory
pointed by a pointer is not lost/leaking to help these tools.
* jk/leak-checkers:
add UNLEAK annotation for reducing leak false positives
set_git_dir: handle feeding gitdir to itself
repository: free fields before overwriting them
reset: free allocated tree buffers
reset: make tree counting less confusing
config: plug user_config leak
update-index: fix cache entry leak in add_one_file()
add: free leaked pathspec after add_files_to_cache()
test-lib: set LSAN_OPTIONS to abort by default
test-lib: --valgrind should not override --verbose-log
Our hashmap implementation in hashmap.[ch] is not thread-safe when
adding a new item needs to expand the hashtable by rehashing; add
an API to disable the automatic rehashing to work it around.
* jh/hashmap-disable-counting:
hashmap: add API to disable item counting when threaded
The long-standing rule that an in-core lockfile instance, once it
is used, must not be freed, has been lifted and the lockfile and
tempfile APIs have been updated to reduce the chance of programming
errors.
* jk/incore-lockfile-removal:
stop leaking lock structs in some simple cases
ref_lock: stop leaking lock_files
lockfile: update lifetime requirements in documentation
tempfile: auto-allocate tempfiles on heap
tempfile: remove deactivated list entries
tempfile: use list.h for linked list
tempfile: release deactivated strbufs instead of resetting
tempfile: robustify cleanup handler
tempfile: factor out deactivation
tempfile: factor out activation
tempfile: replace die("BUG") with BUG()
tempfile: handle NULL tempfile pointers gracefully
tempfile: prefer is_tempfile_active to bare access
lockfile: do not rollback lock on failed close
tempfile: do not delete tempfile on failed close
always check return value of close_tempfile
verify_signed_buffer: prefer close_tempfile() to close()
setup_temporary_shallow: move tempfile struct into function
setup_temporary_shallow: avoid using inactive tempfile
write_index_as_tree: cleanup tempfile on error
"git gc" and friends when multiple worktrees are used off of a
single repository did not consider the index and per-worktree refs
of other worktrees as the root for reachability traversal, making
objects that are in use only in other worktrees to be subject to
garbage collection.
* nd/prune-in-worktree:
refs.c: reindent get_submodule_ref_store()
refs.c: remove fallback-to-main-store code get_submodule_ref_store()
rev-list: expose and document --single-worktree
revision.c: --reflog add HEAD reflog from all worktrees
files-backend: make reflog iterator go through per-worktree reflog
revision.c: --all adds HEAD from all worktrees
refs: remove dead for_each_*_submodule()
refs.c: move for_each_remote_ref_submodule() to submodule.c
revision.c: use refs_for_each*() instead of for_each_*_submodule()
refs: add refs_head_ref()
refs: move submodule slash stripping code to get_submodule_ref_store
refs.c: refactor get_submodule_ref_store(), share common free block
revision.c: --indexed-objects add objects from all worktrees
revision.c: refactor add_index_objects_to_pending()
refs.c: use is_dir_sep() in resolve_gitlink_ref()
revision.h: new flag in struct rev_info wrt. worktree-related refs
* ma/split-symref-update-fix:
refs/files-backend: add `refname`, not "HEAD", to list
refs/files-backend: correct return value in lock_ref_for_update
refs/files-backend: fix memory leak in lock_ref_for_update
refs/files-backend: add longer-scoped copy of string to list
* mh/notes-cleanup:
load_subtree(): check that `prefix_len` is in the expected range
load_subtree(): declare some variables to be `size_t`
hex_to_bytes(): simpler replacement for `get_oid_hex_segment()`
get_oid_hex_segment(): don't pad the rest of `oid`
load_subtree(): combine some common code
get_oid_hex_segment(): return 0 on success
load_subtree(): only consider blobs to be potential notes
load_subtree(): check earlier whether an internal node is a tree entry
load_subtree(): separate logic for internal vs. terminal entries
load_subtree(): fix incorrect comment
load_subtree(): reduce the scope of some local variables
load_subtree(): remove unnecessary conditional
notes: make GET_NIBBLE macro more robust
gc: call fscanf() with %<len>s, not %<len>c, when reading hostname
Earlier in this codepath, we (ab)used "%<len>c" to read the hostname
recorded in the lockfile into locking_host[HOST_NAME_MAX + 1] while
substituting <len> with the actual value of HOST_NAME_MAX.
This turns out to be incorrect, as it is an instruction to read
exactly the specified number of bytes. Because we are trying to
read at most that many bytes, we should be using "%<len>s" instead.
Helped-by: A. Wilcox <awilfox@adelielinux.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
add test for bug in git-mv for recursive submodules
When using git-mv with a submodule it will detect that and update the
paths for its configurations (.gitmodules, worktree and gitfile). This
does not work for recursive submodules where a user renames the root
submodule.
We discovered this fact when working on on-demand fetch for renamed
submodules. Lets add a test to document.
Signed-off-by: Heiko Voigt <hvoigt@hvoigt.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Set curl as the runtime default when it is available.
When linked against older curl versions (< 7_34_0) or without curl,
use the legacy imap implementation.
The goal is to validate feature parity between the legacy and
the curl implementation, deprecate the legacy implementation
later on and in the long term, hopefully drop it altogether.
Signed-off-by: Nicolas Morey-Chaisemartin <nicolas@morey-chaisemartin.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
imap_send: setup_curl: retreive credentials if not set in config file
Up to this point, the curl mode only supported getting the username
and password from the gitconfig file while the legacy mode could also
fetch them using the credential API.
Signed-off-by: Nicolas Morey-Chaisemartin <nicolas@morey-chaisemartin.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
curl_append_msgs_to_imap always returned 0, whether curl failed or not.
Return a proper status so git imap-send will exit with an error code
if something wrong happened.
Signed-off-by: Nicolas Morey-Chaisemartin <nicolas@morey-chaisemartin.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
commit-template: change a message to be more intuitive
It's not good to use the phrase 'do not touch' to convey the
information that the cut-line should not be modified or removed as
it could possibly be mis-interpreted by a person who doesn't know
that the word 'touch' has the meaning of 'tamper with'. Further, it
could make translations a little difficult as it might not have the
intended meaning in a few languages when translated as such.
So, use more intuitive terms in the sentence.
Signed-off-by: Kaartic Sivaraam <kaarticsivaraam91196@gmail.com> Helped-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
test-lib: don't use ulimit in test prerequisites on cygwin
On cygwin (and MinGW), the 'ulimit' built-in bash command does not have
the desired effect of limiting the resources of new processes, at least
for the stack and file descriptors. However, it always returns success
and leads to several test prerequisites being erroneously set to true.
Add a check for cygwin and MinGW to the prerequisite expressions, using
a 'test_have_prereq !MINGW,!CYGWIN' clause, to guard against using ulimit.
This affects the prerequisite expressions for the ULIMIT_STACK_SIZE,
CMDLINE_LIMIT and ULIMIT_FILE_DESCRIPTORS prerequisites.
Signed-off-by: Ramsay Jones <ramsay@ramsayjones.plus.com> Reviewed-by: Jonathan Nieder <jrnieder@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
read_pack_header: handle signed/unsigned comparison in read result
The result of read_in_full() may be -1 if we saw an error.
But in comparing it to a sizeof() result, that "-1" will be
promoted to size_t. In fact, the largest possible size_t
which is much bigger than our struct size. This means that
our "< sizeof(header)" error check won't trigger.
In practice, we'd go on to read uninitialized memory and
compare it to the PACK signature, which is likely to fail.
But we shouldn't get there.
We can fix this by making a direct "!=" comparison to the
requested size, rather than "<". This means that errors get
lumped in with short reads, but that's sufficient for our
purposes here. There's no PH_ERROR tp represent our case.
And anyway, this function reads from pipes and network
sockets. A network error may racily appear as EOF to us
anyway if there's data left in the socket buffers.
Signed-off-by: Jeff King <peff@peff.net> Reviewed-by: Jonathan Nieder <jrnieder@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
The store_write_section() and store_write_pairs() functions
are basically high-level wrappers around write(). But their
return values are flipped from our usual convention, using
"1" for success and "0" for failure.
Let's flip them to follow the usual write() conventions and
update all callers. As these are local to config.c, it's
unlikely that we'd have new callers in any topics in flight
(which would be silently broken by our change). But just to
be on the safe side, let's rename them to just
write_section() and write_pairs(). That also accentuates
their relationship with write().
Signed-off-by: Jeff King <peff@peff.net> Reviewed-by: Jonathan Nieder <jrnieder@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
notes-merge: use ssize_t for write_in_full() return value
We store the return value of write_in_full() in a long,
though the return is actually an ssize_t. This probably
doesn't matter much in practice (since the buffer size is
alredy an unsigned long), but it might if the size if
between what can be represented in "long" and "unsigned
long", and if your size_t is larger than a "long" (as it is
on 64-bit Windows).
Signed-off-by: Jeff King <peff@peff.net> Reviewed-by: Jonathan Nieder <jrnieder@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
pkt-line: check write_in_full() errors against "< 0"
As with the previous two commits, we prefer to check
write_in_full()'s return value to see if it is negative,
rather than comparing it to the input length.
These cases actually flip the logic to check for success,
making conversion a little different than in other cases. We
could of course write:
if (write_in_full(...) >= 0)
return 0;
return error(...);
But our usual method of spelling write() error checks is
just "< 0". So let's flip the logic for each of these
conditionals to our usual style.
Signed-off-by: Jeff King <peff@peff.net> Reviewed-by: Jonathan Nieder <jrnieder@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
convert less-trivial versions of "write_in_full() != len"
The prior commit converted many sites to check the return
value of write_in_full() for negativity, rather than a
mismatch with the input length. This patch covers similar
cases, but where the return value is stored in an
intermediate variable. These should get the same treatment,
but they need to be reviewed more carefully since it would
be a bug if the return value is stored in an unsigned type
(which indeed, it is in one of the cases).
Signed-off-by: Jeff King <peff@peff.net> Reviewed-by: Jonathan Nieder <jrnieder@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
The return value of write_in_full() is either "-1", or the
requested number of bytes[1]. If we make a partial write
before seeing an error, we still return -1, not a partial
value. This goes back to f6aa66cb95 (write_in_full: really
write in full or return error on disk full., 2007-01-11).
So checking anything except "was the return value negative"
is pointless. And there are a couple of reasons not to do
so:
1. It can do a funny signed/unsigned comparison. If your
"len" is signed (e.g., a size_t) then the compiler will
promote the "-1" to its unsigned variant.
This works out for "!= len" (unless you really were
trying to write the maximum size_t bytes), but is a
bug if you check "< len" (an example of which was fixed
recently in config.c).
We should avoid promoting the mental model that you
need to check the length at all, so that new sites are
not tempted to copy us.
2. Checking for a negative value is shorter to type,
especially when the length is an expression.
3. Linus says so. In d34cf19b89 (Clean up write_in_full()
users, 2007-01-11), right after the write_in_full()
semantics were changed, he wrote:
I really wish every "write_in_full()" user would just
check against "<0" now, but this fixes the nasty and
stupid ones.
Appeals to authority aside, this makes it clear that
writing it this way does not have an intentional
benefit. It's a historical curiosity that we never
bothered to clean up (and which was undoubtedly
cargo-culted into new sites).
So let's convert these obviously-correct cases (this
includes write_str_in_full(), which is just a wrapper for
write_in_full()).
[1] A careful reader may notice there is one way that
write_in_full() can return a different value. If we ask
write() to write N bytes and get a return value that is
_larger_ than N, we could return a larger total. But
besides the fact that this would imply a totally broken
version of write(), it would already invoke undefined
behavior. Our internal remaining counter is an unsigned
size_t, which means that subtracting too many byte will
wrap it around to a very large number. So we'll instantly
begin reading off the end of the buffer, trying to write
gigabytes (or petabytes) of data.
Signed-off-by: Jeff King <peff@peff.net> Reviewed-by: Jonathan Nieder <jrnieder@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
get-tar-commit-id: check write_in_full() return against 0
We ask to write 41 bytes and make sure that the return value
is at least 41. This is the same "dangerous" pattern that
was fixed in the prior commit (wherein a negative return
value is promoted to unsigned), though it is not dangerous
here because our "41" is a constant, not an unsigned
variable.
But we should convert it anyway to avoid modeling a
dangerous construct.
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
The return type of write_in_full() is a signed ssize_t,
because we may return "-1" on failure (even if we succeeded
in writing some bytes). But "len" itself is may be an
unsigned type (the function takes a size_t, but of course we
may have something else in the calling function). So while
it seems like:
if (write_in_full(fd, buf, len) < len)
die_errno("write error");
would trigger on error, it won't if "len" is unsigned. The
compiler sees a signed/unsigned comparison and promotes the
signed value, resulting in (size_t)-1, the highest possible
size_t (or again, whatever type the caller has). This cannot
possibly be smaller than "len", and so the conditional can
never trigger.
I scoured the code base for cases of this, but it turns out
that these two in git_config_set_multivar_in_file_gently()
are the only ones. Here our "len" is the difference between
two size_t variables, making the result an unsigned size_t.
We can fix this by just checking for a negative return value
directly, as write_in_full() will never return any value
except -1 or the full count.
There's no addition to the test suite here, since you need
to convince write() to fail in order to see the problem. The
simplest reproduction recipe I came up with is to trigger
ENOSPC:
# make a limited-size filesystem
dd if=/dev/zero of=small.disk bs=1M count=1
mke2fs small.disk
mkdir mnt
sudo mount -o loop small.disk mnt
cd mnt
sudo chown $USER:$USER .
# make a config file with some content
git config --file=config one.key value
git config --file=config two.key value
# now fill up the disk
dd if=/dev/zero of=fill
# and try to delete a key, which requires copying the rest
# of the file to config.lock, and will fail on write()
git config --file=config --unset two.key
That final command should (and does after this patch)
produce an error message due to the failed write, and leave
the file intact. Instead, it silently ignores the failure
and renames config.lock into place, leaving you with a
totally empty config file!
Reported-by: demerphq <demerphq@gmail.com> Signed-off-by: Jeff King <peff@peff.net> Reviewed-by: Jonathan Nieder <jrnieder@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
While git doesn't track empty directories, git archive can be tricked
into putting some into archives. One way is to construct an empty tree
object, as t5004 does. While that is supported by the object database,
it can't be represented in the index and thus it's unlikely to occur in
the wild.
Another way is using the literal name of a directory in an exclude
pathspec -- its contents are are excluded, but the directory stub is
included. That's inconsistent: exclude pathspecs containing wildcards
don't leave empty directories in the archive.
Yet another way is have a few levels of nested subdirectories (e.g.
d1/d2/d3/file1) and ignoring the entries at the leaves (e.g. file1).
The directories with the ignored content are ignored as well (e.g. d3),
but their empty parents are included (e.g. d2).
As empty directories are not supported by git, they should also not be
written into archives. If an empty directory is really needed then it
can be tracked and archived by placing an empty .gitignore file in it.
There already is a mechanism in place for suppressing empty directories.
When read_tree_recursive() encounters a directory excluded by a pathspec
then it enters it anyway because it might contain included entries. It
calls the callback function before it is able to decide if the directory
is actually needed. For that reason git archive adds directories to a
queue and writes entries for them only when it encounters the first
child item -- but currently only if pathspecs with wildcards are used.
Queue *all* directories, no matter if there even are pathspecs present.
This prevents git archive from writing entries for empty directories in
all cases.
Suggested-by: Jeff King <peff@peff.net> Signed-off-by: Rene Scharfe <l.s.r@web.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
replace-objects: evaluate replacement refs without using the object store
Pass DO_FOR_EACH_INCLUDE_BROKEN when iterating over replacement refs
so that the iteration does not require opening the named objects from
the object store. This avoids a dependency cycle between object access
and replace ref iteration.
Moreover the ref subsystem has not been migrated yet to access the
object store via passed in repository objects. As a result, without
this patch, iterating over replace refs in a repository other than
the_repository it produces errors:
Noticed while adapting the object store (and in particular its
evaluation of replace refs) to handle arbitrary repositories.
Signed-off-by: Stefan Beller <sbeller@google.com> Signed-off-by: Jonathan Nieder <jrnieder@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>