From: Junio C Hamano Date: Tue, 22 Aug 2017 17:29:16 +0000 (-0700) Subject: Merge branch 'mh/packed-ref-store' X-Git-Tag: v2.15.0-rc0~156 X-Git-Url: https://git.lorimer.id.au/gitweb.git/diff_plain/44c2339e55df11b2cfd8bdc28ceee6b4d1ca1928?hp=-c Merge branch 'mh/packed-ref-store' The "ref-store" code reorganization continues. * mh/packed-ref-store: (32 commits) files-backend: cheapen refname_available check when locking refs packed_ref_store: handle a packed-refs file that is a symlink read_packed_refs(): die if `packed-refs` contains bogus data t3210: add some tests of bogus packed-refs file contents repack_without_refs(): don't lock or unlock the packed refs commit_packed_refs(): remove call to `packed_refs_unlock()` clear_packed_ref_cache(): don't protest if the lock is held packed_refs_unlock(), packed_refs_is_locked(): new functions packed_refs_lock(): report errors via a `struct strbuf *err` packed_refs_lock(): function renamed from lock_packed_refs() commit_packed_refs(): use a staging file separate from the lockfile commit_packed_refs(): report errors rather than dying packed_ref_store: make class into a subclass of `ref_store` packed-backend: new module for handling packed references packed_read_raw_ref(): new function, replacing `resolve_packed_ref()` packed_ref_store: support iteration packed_peel_ref(): new function, extracted from `files_peel_ref()` repack_without_refs(): take a `packed_ref_store *` parameter get_packed_ref(): take a `packed_ref_store *` parameter rollback_packed_refs(): take a `packed_ref_store *` parameter ... --- 44c2339e55df11b2cfd8bdc28ceee6b4d1ca1928 diff --combined Makefile index 461c845d33,aff9c6d7e2..86ec29202b --- a/Makefile +++ b/Makefile @@@ -19,34 -19,16 +19,34 @@@ all: # have been written to the final string if enough space had been available. # # Define FREAD_READS_DIRECTORIES if you are on a system which succeeds -# when attempting to read from an fopen'ed directory. +# when attempting to read from an fopen'ed directory (or even to fopen +# 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. git-grep will be -# able to use Perl-compatible regular expressions. -# -# Define LIBPCREDIR=/foo/bar if your libpcre header and library files are in -# /foo/bar/include and /foo/bar/lib directories. +# 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. +# +# When using USE_LIBPCRE1, define NO_LIBPCRE1_JIT if the PCRE v1 +# library is compiled without --enable-jit. We will auto-detect +# whether the version of the PCRE v1 library in use has JIT support at +# all, but we unfortunately can't auto-detect whether JIT support +# hasn't been compiled in in an otherwise JIT-supporting version. If +# you have link-time errors about a missing `pcre_jit_exec` define +# this, or recompile PCRE v1 with --enable-jit. +# +# Define LIBPCREDIR=/foo/bar if your PCRE header and library files are +# in /foo/bar/include and /foo/bar/lib directories. Which version of +# PCRE this points to determined by the USE_LIBPCRE1 and USE_LIBPCRE2 +# variables. # # Define HAVE_ALLOCA_H if you have working alloca(3) defined in that header. # @@@ -162,12 -144,6 +162,12 @@@ # algorithm. This is slower, but may detect attempted collision attacks. # Takes priority over other *_SHA1 knobs. # +# Define DC_SHA1_SUBMODULE in addition to DC_SHA1 to use the +# sha1collisiondetection shipped as a submodule instead of the +# non-submodule copy in sha1dc/. This is an experimental option used +# by the git project to migrate to using sha1collisiondetection as a +# submodule. +# # Define OPENSSL_SHA1 environment variable when running make to link # with the SHA1 routine from openssl library. # @@@ -742,7 -718,6 +742,7 @@@ LIB_OBJS += argv-array. LIB_OBJS += attr.o LIB_OBJS += base85.o LIB_OBJS += bisect.o +LIB_OBJS += blame.o LIB_OBJS += blob.o LIB_OBJS += branch.o LIB_OBJS += bulk-checkin.o @@@ -842,11 -817,11 +842,12 @@@ LIB_OBJS += reflog-walk. LIB_OBJS += refs.o LIB_OBJS += refs/files-backend.o LIB_OBJS += refs/iterator.o + LIB_OBJS += refs/packed-backend.o LIB_OBJS += refs/ref-cache.o LIB_OBJS += ref-filter.o LIB_OBJS += remote.o LIB_OBJS += replace_object.o +LIB_OBJS += repository.o LIB_OBJS += rerere.o LIB_OBJS += resolve-undo.o LIB_OBJS += revision.o @@@ -868,7 -843,6 +869,7 @@@ LIB_OBJS += streaming. LIB_OBJS += string-list.o LIB_OBJS += submodule.o LIB_OBJS += submodule-config.o +LIB_OBJS += sub-process.o LIB_OBJS += symlinks.o LIB_OBJS += tag.o LIB_OBJS += tempfile.o @@@ -1010,10 -984,6 +1011,10 @@@ EXTLIBS GIT_USER_AGENT = git/$(GIT_VERSION) +ifeq ($(wildcard sha1collisiondetection/lib/sha1.h),sha1collisiondetection/lib/sha1.h) +DC_SHA1_SUBMODULE = auto +endif + include config.mak.uname -include config.mak.autogen -include config.mak @@@ -1022,19 -992,6 +1023,19 @@@ ifdef DEVELOPE CFLAGS += $(DEVELOPER_CFLAGS) endif +comma := , +empty := +space := $(empty) $(empty) + +ifdef SANITIZE +SANITIZERS := $(foreach flag,$(subst $(comma),$(space),$(SANITIZE)),$(flag)) +BASIC_CFLAGS += -fsanitize=$(SANITIZE) -fno-sanitize-recover=$(SANITIZE) +BASIC_CFLAGS += -fno-omit-frame-pointer +ifneq ($(filter undefined,$(SANITIZERS)),) +BASIC_CFLAGS += -DNO_UNALIGNED_LOADS +endif +endif + ifndef sysconfdir ifeq ($(prefix),/usr) sysconfdir = /etc @@@ -1129,29 -1086,13 +1130,29 @@@ ifdef NO_LIBGEN_ COMPAT_OBJS += compat/basename.o endif -ifdef USE_LIBPCRE - BASIC_CFLAGS += -DUSE_LIBPCRE - ifdef LIBPCREDIR - BASIC_CFLAGS += -I$(LIBPCREDIR)/include - EXTLIBS += -L$(LIBPCREDIR)/$(lib) $(CC_LD_DYNPATH)$(LIBPCREDIR)/$(lib) +USE_LIBPCRE1 ?= $(USE_LIBPCRE) + +ifneq (,$(USE_LIBPCRE1)) + ifdef USE_LIBPCRE2 +$(error Only set USE_LIBPCRE1 (or its alias USE_LIBPCRE) or USE_LIBPCRE2, not both!) endif + + BASIC_CFLAGS += -DUSE_LIBPCRE1 EXTLIBS += -lpcre + +ifdef NO_LIBPCRE1_JIT + BASIC_CFLAGS += -DNO_LIBPCRE1_JIT +endif +endif + +ifdef USE_LIBPCRE2 + BASIC_CFLAGS += -DUSE_LIBPCRE2 + EXTLIBS += -lpcre2-8 +endif + +ifdef LIBPCREDIR + BASIC_CFLAGS += -I$(LIBPCREDIR)/include + EXTLIBS += -L$(LIBPCREDIR)/$(lib) $(CC_LD_DYNPATH)$(LIBPCREDIR)/$(lib) endif ifdef HAVE_ALLOCA_H @@@ -1472,22 -1413,9 +1473,22 @@@ ifdef APPLE_COMMON_CRYPT BASIC_CFLAGS += -DSHA1_APPLE else DC_SHA1 := YesPlease +ifdef DC_SHA1_SUBMODULE + LIB_OBJS += sha1collisiondetection/lib/sha1.o + LIB_OBJS += sha1collisiondetection/lib/ubc_check.o + BASIC_CFLAGS += -DDC_SHA1_SUBMODULE +else LIB_OBJS += sha1dc/sha1.o LIB_OBJS += sha1dc/ubc_check.o - BASIC_CFLAGS += -DSHA1_DC +endif + BASIC_CFLAGS += \ + -DSHA1_DC \ + -DSHA1DC_NO_STANDARD_INCLUDES \ + -DSHA1DC_INIT_SAFE_HASH_DEFAULT=0 \ + -DSHA1DC_CUSTOM_INCLUDE_SHA1_C="\"cache.h\"" \ + -DSHA1DC_CUSTOM_TRAILING_INCLUDE_SHA1_C="\"sha1dc_git.c\"" \ + -DSHA1DC_CUSTOM_TRAILING_INCLUDE_SHA1_H="\"sha1dc_git.h\"" \ + -DSHA1DC_CUSTOM_INCLUDE_UBC_CHECK_C="\"git-compat-util.h\"" endif endif endif @@@ -2221,33 -2149,12 +2222,33 @@@ LOCALIZED_SH += t/t0200/test.s LOCALIZED_PERL += t/t0200/test.perl endif +## Note that this is meant to be run only by the localization coordinator +## under a very controlled condition, i.e. (1) it is to be run in a +## Git repository (not a tarball extract), (2) any local modifications +## will be lost. +## Gettext tools cannot work with our own custom PRItime type, so +## we replace PRItime with PRIuMAX. We need to update this to +## PRIdMAX if we switch to a signed type later. + po/git.pot: $(GENERATED_H) FORCE + # All modifications will be reverted at the end, so we do not + # want to have any local change. + git diff --quiet HEAD && git diff --quiet --cached + + @for s in $(LOCALIZED_C) $(LOCALIZED_SH) $(LOCALIZED_PERL); \ + do \ + sed -e 's|PRItime|PRIuMAX|g' <"$$s" >"$$s+" && \ + cat "$$s+" >"$$s" && rm "$$s+"; \ + done + $(QUIET_XGETTEXT)$(XGETTEXT) -o$@+ $(XGETTEXT_FLAGS_C) $(LOCALIZED_C) $(QUIET_XGETTEXT)$(XGETTEXT) -o$@+ --join-existing $(XGETTEXT_FLAGS_SH) \ $(LOCALIZED_SH) $(QUIET_XGETTEXT)$(XGETTEXT) -o$@+ --join-existing $(XGETTEXT_FLAGS_PERL) \ $(LOCALIZED_PERL) + + # Reverting the munged source, leaving only the updated $@ + git reset --hard mv $@+ $@ .PHONY: pot @@@ -2332,11 -2239,8 +2333,11 @@@ GIT-BUILD-OPTIONS: FORC @echo TAR=\''$(subst ','\'',$(subst ','\'',$(TAR)))'\' >>$@+ @echo NO_CURL=\''$(subst ','\'',$(subst ','\'',$(NO_CURL)))'\' >>$@+ @echo NO_EXPAT=\''$(subst ','\'',$(subst ','\'',$(NO_EXPAT)))'\' >>$@+ - @echo USE_LIBPCRE=\''$(subst ','\'',$(subst ','\'',$(USE_LIBPCRE)))'\' >>$@+ + @echo USE_LIBPCRE1=\''$(subst ','\'',$(subst ','\'',$(USE_LIBPCRE1)))'\' >>$@+ + @echo USE_LIBPCRE2=\''$(subst ','\'',$(subst ','\'',$(USE_LIBPCRE2)))'\' >>$@+ + @echo NO_LIBPCRE1_JIT=\''$(subst ','\'',$(subst ','\'',$(NO_LIBPCRE1_JIT)))'\' >>$@+ @echo NO_PERL=\''$(subst ','\'',$(subst ','\'',$(NO_PERL)))'\' >>$@+ + @echo NO_PTHREADS=\''$(subst ','\'',$(subst ','\'',$(NO_PTHREADS)))'\' >>$@+ @echo NO_PYTHON=\''$(subst ','\'',$(subst ','\'',$(NO_PYTHON)))'\' >>$@+ @echo NO_UNIX_SOCKETS=\''$(subst ','\'',$(subst ','\'',$(NO_UNIX_SOCKETS)))'\' >>$@+ @echo PAGER_ENV=\''$(subst ','\'',$(subst ','\'',$(PAGER_ENV)))'\' >>$@+ @@@ -2367,9 -2271,6 +2368,9 @@@ endi ifdef GIT_PERF_MAKE_OPTS @echo GIT_PERF_MAKE_OPTS=\''$(subst ','\'',$(subst ','\'',$(GIT_PERF_MAKE_OPTS)))'\' >>$@+ endif +ifdef GIT_PERF_MAKE_COMMAND + @echo GIT_PERF_MAKE_COMMAND=\''$(subst ','\'',$(subst ','\'',$(GIT_PERF_MAKE_COMMAND)))'\' >>$@+ +endif ifdef GIT_INTEROP_MAKE_OPTS @echo GIT_INTEROP_MAKE_OPTS=\''$(subst ','\'',$(subst ','\'',$(GIT_INTEROP_MAKE_OPTS)))'\' >>$@+ endif diff --combined refs.c index fe4c59aa8b,5880c12372..3d549a8970 --- a/refs.c +++ b/refs.c @@@ -3,7 -3,6 +3,7 @@@ */ #include "cache.h" +#include "config.h" #include "hashmap.h" #include "lockfile.h" #include "iterator.h" @@@ -174,6 -173,24 +174,24 @@@ int refname_is_safe(const char *refname return 1; } + /* + * Return true if refname, which has the specified oid and flags, can + * be resolved to an object in the database. If the referred-to object + * does not exist, emit a warning and return false. + */ + int ref_resolves_to_object(const char *refname, + const struct object_id *oid, + unsigned int flags) + { + if (flags & REF_ISBROKEN) + return 0; + if (!has_sha1_file(oid->hash)) { + error("%s does not point to a valid object!", refname); + return 0; + } + return 1; + } + char *refs_resolve_refdup(struct ref_store *refs, const char *refname, int resolve_flags, unsigned char *sha1, int *flags) @@@ -230,7 -247,7 +248,7 @@@ static int filter_refs(const char *refn { struct ref_filter *filter = (struct ref_filter *)data; - if (wildmatch(filter->pattern, refname, 0, NULL)) + if (wildmatch(filter->pattern, refname, 0)) return 0; return filter->fn(refname, oid, flags, filter->cb_data); } @@@ -818,7 -835,7 +836,7 @@@ int read_ref_at(const char *refname, un for_each_reflog_ent_reverse(refname, read_ref_at_ent, &cb); if (!cb.reccnt) { - if (flags & GET_SHA1_QUIETLY) + if (flags & GET_OID_QUIETLY) exit(128); else die("Log for %s is empty.", refname); @@@ -1160,7 -1177,7 +1178,7 @@@ int ref_is_hidden(const char *refname, const char *match = hide_refs->items[i].string; const char *subject; int neg = 0; - int len; + const char *p; if (*match == '!') { neg = 1; @@@ -1175,9 -1192,10 +1193,9 @@@ } /* refname can be NULL when namespaces are used. */ - if (!subject || !starts_with(subject, match)) - continue; - len = strlen(match); - if (!subject[len] || subject[len] == '/') + if (subject && + skip_prefix(subject, match, &p) && + (!*p || *p == '/')) return !neg; } return 0; @@@ -1524,8 -1542,7 +1542,8 @@@ struct ref_store_hash_entr char name[FLEX_ARRAY]; }; -static int ref_store_hash_cmp(const void *entry, const void *entry_or_key, +static int ref_store_hash_cmp(const void *unused_cmp_data, + const void *entry, const void *entry_or_key, const void *keydata) { const struct ref_store_hash_entry *e1 = entry, *e2 = entry_or_key; @@@ -1608,7 -1625,7 +1626,7 @@@ static void register_ref_store_map(stru const char *name) { if (!map->tablesize) - hashmap_init(map, ref_store_hash_cmp, 0); + hashmap_init(map, ref_store_hash_cmp, NULL, 0); if (hashmap_put(map, alloc_ref_store_hash_entry(name, refs))) die("BUG: %s ref_store '%s' initialized twice", type, name); diff --combined refs/files-backend.c index 0404f2c233,f2a420c611..5cca55510b --- a/refs/files-backend.c +++ b/refs/files-backend.c @@@ -1,8 -1,8 +1,9 @@@ #include "../cache.h" +#include "../config.h" #include "../refs.h" #include "refs-internal.h" #include "ref-cache.h" + #include "packed-backend.h" #include "../iterator.h" #include "../dir-iterator.h" #include "../lockfile.h" @@@ -15,39 -15,6 +16,6 @@@ struct ref_lock struct object_id old_oid; }; - /* - * Return true if refname, which has the specified oid and flags, can - * be resolved to an object in the database. If the referred-to object - * does not exist, emit a warning and return false. - */ - static int ref_resolves_to_object(const char *refname, - const struct object_id *oid, - unsigned int flags) - { - if (flags & REF_ISBROKEN) - return 0; - if (!has_sha1_file(oid->hash)) { - error("%s does not point to a valid object!", refname); - return 0; - } - return 1; - } - - struct packed_ref_cache { - struct ref_cache *cache; - - /* - * Count of references to the data structure in this instance, - * including the pointer from files_ref_store::packed if any. - * The data will not be freed as long as the reference count - * is nonzero. - */ - unsigned int referrers; - - /* The metadata from when this packed-refs cache was read */ - struct stat_validity validity; - }; - /* * Future: need to be in "struct repository" * when doing a full libification. @@@ -58,54 -25,12 +26,12 @@@ struct files_ref_store char *gitdir; char *gitcommondir; - char *packed_refs_path; struct ref_cache *loose; - struct packed_ref_cache *packed; - /* - * Lock used for the "packed-refs" file. Note that this (and - * thus the enclosing `files_ref_store`) must not be freed. - */ - struct lock_file packed_refs_lock; + struct ref_store *packed_ref_store; }; - /* - * Increment the reference count of *packed_refs. - */ - static void acquire_packed_ref_cache(struct packed_ref_cache *packed_refs) - { - packed_refs->referrers++; - } - - /* - * Decrease the reference count of *packed_refs. If it goes to zero, - * free *packed_refs and return true; otherwise return false. - */ - static int release_packed_ref_cache(struct packed_ref_cache *packed_refs) - { - if (!--packed_refs->referrers) { - free_ref_cache(packed_refs->cache); - stat_validity_clear(&packed_refs->validity); - free(packed_refs); - return 1; - } else { - return 0; - } - } - - static void clear_packed_ref_cache(struct files_ref_store *refs) - { - if (refs->packed) { - struct packed_ref_cache *packed_refs = refs->packed; - - if (is_lock_file_locked(&refs->packed_refs_lock)) - die("BUG: packed-ref cache cleared while locked"); - refs->packed = NULL; - release_packed_ref_cache(packed_refs); - } - } - static void clear_loose_ref_cache(struct files_ref_store *refs) { if (refs->loose) { @@@ -132,7 -57,8 +58,8 @@@ static struct ref_store *files_ref_stor get_common_dir_noenv(&sb, gitdir); refs->gitcommondir = strbuf_detach(&sb, NULL); strbuf_addf(&sb, "%s/packed-refs", refs->gitcommondir); - refs->packed_refs_path = strbuf_detach(&sb, NULL); + refs->packed_ref_store = packed_ref_store_create(sb.buf, flags); + strbuf_release(&sb); return ref_store; } @@@ -175,156 -101,6 +102,6 @@@ static struct files_ref_store *files_do return refs; } - /* The length of a peeled reference line in packed-refs, including EOL: */ - #define PEELED_LINE_LENGTH 42 - - /* - * The packed-refs header line that we write out. Perhaps other - * traits will be added later. The trailing space is required. - */ - static const char PACKED_REFS_HEADER[] = - "# pack-refs with: peeled fully-peeled \n"; - - /* - * Parse one line from a packed-refs file. Write the SHA1 to sha1. - * Return a pointer to the refname within the line (null-terminated), - * or NULL if there was a problem. - */ - static const char *parse_ref_line(struct strbuf *line, struct object_id *oid) - { - const char *ref; - - if (parse_oid_hex(line->buf, oid, &ref) < 0) - return NULL; - if (!isspace(*ref++)) - return NULL; - - if (isspace(*ref)) - return NULL; - - if (line->buf[line->len - 1] != '\n') - return NULL; - line->buf[--line->len] = 0; - - return ref; - } - - /* - * Read from `packed_refs_file` into a newly-allocated - * `packed_ref_cache` and return it. The return value will already - * have its reference count incremented. - * - * A comment line of the form "# pack-refs with: " may contain zero or - * more traits. We interpret the traits as follows: - * - * No traits: - * - * Probably no references are peeled. But if the file contains a - * peeled value for a reference, we will use it. - * - * peeled: - * - * References under "refs/tags/", if they *can* be peeled, *are* - * peeled in this file. References outside of "refs/tags/" are - * probably not peeled even if they could have been, but if we find - * a peeled value for such a reference we will use it. - * - * fully-peeled: - * - * All references in the file that can be peeled are peeled. - * Inversely (and this is more important), any references in the - * file for which no peeled value is recorded is not peelable. This - * trait should typically be written alongside "peeled" for - * compatibility with older clients, but we do not require it - * (i.e., "peeled" is a no-op if "fully-peeled" is set). - */ - static struct packed_ref_cache *read_packed_refs(const char *packed_refs_file) - { - FILE *f; - struct packed_ref_cache *packed_refs = xcalloc(1, sizeof(*packed_refs)); - struct ref_entry *last = NULL; - struct strbuf line = STRBUF_INIT; - enum { PEELED_NONE, PEELED_TAGS, PEELED_FULLY } peeled = PEELED_NONE; - struct ref_dir *dir; - - acquire_packed_ref_cache(packed_refs); - packed_refs->cache = create_ref_cache(NULL, NULL); - packed_refs->cache->root->flag &= ~REF_INCOMPLETE; - - f = fopen(packed_refs_file, "r"); - if (!f) { - if (errno == ENOENT) { - /* - * This is OK; it just means that no - * "packed-refs" file has been written yet, - * which is equivalent to it being empty. - */ - return packed_refs; - } else { - die_errno("couldn't read %s", packed_refs_file); - } - } - - stat_validity_update(&packed_refs->validity, fileno(f)); - - dir = get_ref_dir(packed_refs->cache->root); - while (strbuf_getwholeline(&line, f, '\n') != EOF) { - struct object_id oid; - const char *refname; - const char *traits; - - if (skip_prefix(line.buf, "# pack-refs with:", &traits)) { - if (strstr(traits, " fully-peeled ")) - peeled = PEELED_FULLY; - else if (strstr(traits, " peeled ")) - peeled = PEELED_TAGS; - /* perhaps other traits later as well */ - continue; - } - - refname = parse_ref_line(&line, &oid); - if (refname) { - int flag = REF_ISPACKED; - - if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) { - if (!refname_is_safe(refname)) - die("packed refname is dangerous: %s", refname); - oidclr(&oid); - flag |= REF_BAD_NAME | REF_ISBROKEN; - } - last = create_ref_entry(refname, &oid, flag); - if (peeled == PEELED_FULLY || - (peeled == PEELED_TAGS && starts_with(refname, "refs/tags/"))) - last->flag |= REF_KNOWS_PEELED; - add_ref_entry(dir, last); - continue; - } - if (last && - line.buf[0] == '^' && - line.len == PEELED_LINE_LENGTH && - line.buf[PEELED_LINE_LENGTH - 1] == '\n' && - !get_oid_hex(line.buf + 1, &oid)) { - oidcpy(&last->u.value.peeled, &oid); - /* - * Regardless of what the file header said, - * we definitely know the value of *this* - * reference: - */ - last->flag |= REF_KNOWS_PEELED; - } - } - - fclose(f); - strbuf_release(&line); - - return packed_refs; - } - - static const char *files_packed_refs_path(struct files_ref_store *refs) - { - return refs->packed_refs_path; - } - static void files_reflog_path(struct files_ref_store *refs, struct strbuf *sb, const char *refname) @@@ -370,70 -146,6 +147,6 @@@ static void files_ref_path(struct files } } - /* - * Check that the packed refs cache (if any) still reflects the - * contents of the file. If not, clear the cache. - */ - static void validate_packed_ref_cache(struct files_ref_store *refs) - { - if (refs->packed && - !stat_validity_check(&refs->packed->validity, - files_packed_refs_path(refs))) - clear_packed_ref_cache(refs); - } - - /* - * Get the packed_ref_cache for the specified files_ref_store, - * creating and populating it if it hasn't been read before or if the - * file has been changed (according to its `validity` field) since it - * was last read. On the other hand, if we hold the lock, then assume - * that the file hasn't been changed out from under us, so skip the - * extra `stat()` call in `stat_validity_check()`. - */ - static struct packed_ref_cache *get_packed_ref_cache(struct files_ref_store *refs) - { - const char *packed_refs_file = files_packed_refs_path(refs); - - if (!is_lock_file_locked(&refs->packed_refs_lock)) - validate_packed_ref_cache(refs); - - if (!refs->packed) - refs->packed = read_packed_refs(packed_refs_file); - - return refs->packed; - } - - static struct ref_dir *get_packed_ref_dir(struct packed_ref_cache *packed_ref_cache) - { - return get_ref_dir(packed_ref_cache->cache->root); - } - - static struct ref_dir *get_packed_refs(struct files_ref_store *refs) - { - return get_packed_ref_dir(get_packed_ref_cache(refs)); - } - - /* - * Add a reference to the in-memory packed reference cache. This may - * only be called while the packed-refs file is locked (see - * lock_packed_refs()). To actually write the packed-refs file, call - * commit_packed_refs(). - */ - static void add_packed_ref(struct files_ref_store *refs, - const char *refname, const struct object_id *oid) - { - struct packed_ref_cache *packed_ref_cache = get_packed_ref_cache(refs); - - if (!is_lock_file_locked(&refs->packed_refs_lock)) - die("BUG: packed refs not locked"); - - if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) - die("Reference has invalid format: '%s'", refname); - - add_ref_entry(get_packed_ref_dir(packed_ref_cache), - create_ref_entry(refname, oid, REF_ISPACKED)); - } - /* * Read the loose references from the namespace dirname into dir * (without recursing). dirname must end with '/'. dir must be the @@@ -556,39 -268,6 +269,6 @@@ static struct ref_cache *get_loose_ref_ return refs->loose; } - /* - * Return the ref_entry for the given refname from the packed - * references. If it does not exist, return NULL. - */ - static struct ref_entry *get_packed_ref(struct files_ref_store *refs, - const char *refname) - { - return find_ref_entry(get_packed_refs(refs), refname); - } - - /* - * A loose ref file doesn't exist; check for a packed ref. - */ - static int resolve_packed_ref(struct files_ref_store *refs, - const char *refname, - unsigned char *sha1, unsigned int *flags) - { - struct ref_entry *entry; - - /* - * The loose reference file does not exist; check for a packed - * reference. - */ - entry = get_packed_ref(refs, refname); - if (entry) { - hashcpy(sha1, entry->u.value.oid.hash); - *flags |= REF_ISPACKED; - return 0; - } - /* refname is not a packed reference. */ - return -1; - } - static int files_read_raw_ref(struct ref_store *ref_store, const char *refname, unsigned char *sha1, struct strbuf *referent, unsigned int *type) @@@ -632,7 -311,8 +312,8 @@@ stat_ref if (lstat(path, &st) < 0) { if (errno != ENOENT) goto out; - if (resolve_packed_ref(refs, refname, sha1, type)) { + if (refs_read_raw_ref(refs->packed_ref_store, refname, + sha1, referent, type)) { errno = ENOENT; goto out; } @@@ -671,7 -351,8 +352,8 @@@ * ref is supposed to be, there could still be a * packed ref: */ - if (resolve_packed_ref(refs, refname, sha1, type)) { + if (refs_read_raw_ref(refs->packed_ref_store, refname, + sha1, referent, type)) { errno = EISDIR; goto out; } @@@ -950,11 -631,11 +632,11 @@@ retry /* * If the ref did not exist and we are creating it, - * make sure there is no existing ref that conflicts - * with refname: + * make sure there is no existing packed ref that + * conflicts with refname: */ if (refs_verify_refname_available( - &refs->base, refname, + refs->packed_ref_store, refname, extras, skip, err)) goto error_return; } @@@ -1001,15 -682,9 +683,9 @@@ static int files_peel_ref(struct ref_st * be expensive and (b) loose references anyway usually do not * have REF_KNOWS_PEELED. */ - if (flag & REF_ISPACKED) { - struct ref_entry *r = get_packed_ref(refs, refname); - if (r) { - if (peel_entry(r, 0)) - return -1; - hashcpy(sha1, r->u.value.peeled.hash); - return 0; - } - } + if (flag & REF_ISPACKED && + !refs_peel_ref(refs->packed_ref_store, refname, sha1)) + return 0; return peel_object(base, sha1); } @@@ -1017,7 -692,6 +693,6 @@@ struct files_ref_iterator { struct ref_iterator base; - struct packed_ref_cache *packed_ref_cache; struct ref_iterator *iter0; unsigned int flags; }; @@@ -1070,7 -744,6 +745,6 @@@ static int files_ref_iterator_abort(str if (iter->iter0) ok = ref_iterator_abort(iter->iter0); - release_packed_ref_cache(iter->packed_ref_cache); base_ref_iterator_free(ref_iterator); return ok; } @@@ -1112,18 -785,28 +786,28 @@@ static struct ref_iterator *files_ref_i * (If they've already been read, that's OK; we only need to * guarantee that they're read before the packed refs, not * *how much* before.) After that, we call - * get_packed_ref_cache(), which internally checks whether the - * packed-ref cache is up to date with what is on disk, and - * re-reads it if not. + * packed_ref_iterator_begin(), which internally checks + * whether the packed-ref cache is up to date with what is on + * disk, and re-reads it if not. */ loose_iter = cache_ref_iterator_begin(get_loose_ref_cache(refs), prefix, 1); - iter->packed_ref_cache = get_packed_ref_cache(refs); - acquire_packed_ref_cache(iter->packed_ref_cache); - packed_iter = cache_ref_iterator_begin(iter->packed_ref_cache->cache, - prefix, 0); + /* + * The packed-refs file might contain broken references, for + * example an old version of a reference that points at an + * object that has since been garbage-collected. This is OK as + * long as there is a corresponding loose reference that + * overrides it, and we don't want to emit an error message in + * this case. So ask the packed_ref_store for all of its + * references, and (if needed) do our own check for broken + * ones in files_ref_iterator_advance(), after we have merged + * the packed and loose references. + */ + packed_iter = refs_ref_iterator_begin( + refs->packed_ref_store, prefix, 0, + DO_FOR_EACH_INCLUDE_BROKEN); iter->iter0 = overlay_ref_iterator_begin(loose_iter, packed_iter); iter->flags = flags; @@@ -1255,7 -938,7 +939,7 @@@ static struct ref_lock *lock_ref_sha1_b * our refname. */ if (is_null_oid(&lock->old_oid) && - refs_verify_refname_available(&refs->base, refname, + refs_verify_refname_available(refs->packed_ref_store, refname, extras, skip, err)) { last_errno = ENOTDIR; goto error_return; @@@ -1287,124 -970,6 +971,6 @@@ return lock; } - /* - * Write an entry to the packed-refs file for the specified refname. - * If peeled is non-NULL, write it as the entry's peeled value. - */ - static void write_packed_entry(FILE *fh, const char *refname, - const unsigned char *sha1, - const unsigned char *peeled) - { - fprintf_or_die(fh, "%s %s\n", sha1_to_hex(sha1), refname); - if (peeled) - fprintf_or_die(fh, "^%s\n", sha1_to_hex(peeled)); - } - - /* - * Lock the packed-refs file for writing. Flags is passed to - * hold_lock_file_for_update(). Return 0 on success. On errors, set - * errno appropriately and return a nonzero value. - */ - static int lock_packed_refs(struct files_ref_store *refs, int flags) - { - static int timeout_configured = 0; - static int timeout_value = 1000; - struct packed_ref_cache *packed_ref_cache; - - files_assert_main_repository(refs, "lock_packed_refs"); - - if (!timeout_configured) { - git_config_get_int("core.packedrefstimeout", &timeout_value); - timeout_configured = 1; - } - - if (hold_lock_file_for_update_timeout( - &refs->packed_refs_lock, files_packed_refs_path(refs), - flags, timeout_value) < 0) - return -1; - - /* - * Now that we hold the `packed-refs` lock, make sure that our - * cache matches the current version of the file. Normally - * `get_packed_ref_cache()` does that for us, but that - * function assumes that when the file is locked, any existing - * cache is still valid. We've just locked the file, but it - * might have changed the moment *before* we locked it. - */ - validate_packed_ref_cache(refs); - - packed_ref_cache = get_packed_ref_cache(refs); - /* Increment the reference count to prevent it from being freed: */ - acquire_packed_ref_cache(packed_ref_cache); - return 0; - } - - /* - * Write the current version of the packed refs cache from memory to - * disk. The packed-refs file must already be locked for writing (see - * lock_packed_refs()). Return zero on success. On errors, set errno - * and return a nonzero value - */ - static int commit_packed_refs(struct files_ref_store *refs) - { - struct packed_ref_cache *packed_ref_cache = - get_packed_ref_cache(refs); - int ok, error = 0; - int save_errno = 0; - FILE *out; - struct ref_iterator *iter; - - files_assert_main_repository(refs, "commit_packed_refs"); - - if (!is_lock_file_locked(&refs->packed_refs_lock)) - die("BUG: packed-refs not locked"); - - out = fdopen_lock_file(&refs->packed_refs_lock, "w"); - if (!out) - die_errno("unable to fdopen packed-refs descriptor"); - - fprintf_or_die(out, "%s", PACKED_REFS_HEADER); - - iter = cache_ref_iterator_begin(packed_ref_cache->cache, NULL, 0); - while ((ok = ref_iterator_advance(iter)) == ITER_OK) { - struct object_id peeled; - int peel_error = ref_iterator_peel(iter, &peeled); - - write_packed_entry(out, iter->refname, iter->oid->hash, - peel_error ? NULL : peeled.hash); - } - - if (ok != ITER_DONE) - die("error while iterating over references"); - - if (commit_lock_file(&refs->packed_refs_lock)) { - save_errno = errno; - error = -1; - } - release_packed_ref_cache(packed_ref_cache); - errno = save_errno; - return error; - } - - /* - * Rollback the lockfile for the packed-refs file, and discard the - * in-memory packed reference cache. (The packed-refs file will be - * read anew if it is needed again after this function is called.) - */ - static void rollback_packed_refs(struct files_ref_store *refs) - { - struct packed_ref_cache *packed_ref_cache = - get_packed_ref_cache(refs); - - files_assert_main_repository(refs, "rollback_packed_refs"); - - if (!is_lock_file_locked(&refs->packed_refs_lock)) - die("BUG: packed-refs not locked"); - rollback_lock_file(&refs->packed_refs_lock); - release_packed_ref_cache(packed_ref_cache); - clear_packed_ref_cache(refs); - } - struct ref_to_prune { struct ref_to_prune *next; unsigned char sha1[20]; @@@ -1527,12 -1092,11 +1093,11 @@@ static int files_pack_refs(struct ref_s files_downcast(ref_store, REF_STORE_WRITE | REF_STORE_ODB, "pack_refs"); struct ref_iterator *iter; - struct ref_dir *packed_refs; int ok; struct ref_to_prune *refs_to_prune = NULL; + struct strbuf err = STRBUF_INIT; - lock_packed_refs(refs, LOCK_DIE_ON_ERROR); - packed_refs = get_packed_refs(refs); + packed_refs_lock(refs->packed_ref_store, LOCK_DIE_ON_ERROR, &err); iter = cache_ref_iterator_begin(get_loose_ref_cache(refs), NULL, 0); while ((ok = ref_iterator_advance(iter)) == ITER_OK) { @@@ -1541,8 -1105,6 +1106,6 @@@ * in the packed ref cache. If the reference should be * pruned, also add it to refs_to_prune. */ - struct ref_entry *packed_entry; - if (!should_pack_ref(iter->refname, iter->oid, iter->flags, flags)) continue; @@@ -1553,17 -1115,7 +1116,7 @@@ * we don't copy the peeled status, because we want it * to be re-peeled. */ - packed_entry = find_ref_entry(packed_refs, iter->refname); - if (packed_entry) { - /* Overwrite existing packed entry with info from loose entry */ - packed_entry->flag = REF_ISPACKED; - oidcpy(&packed_entry->u.value.oid, iter->oid); - } else { - packed_entry = create_ref_entry(iter->refname, iter->oid, - REF_ISPACKED); - add_ref_entry(packed_refs, packed_entry); - } - oidclr(&packed_entry->u.value.peeled); + add_packed_ref(refs->packed_ref_store, iter->refname, iter->oid); /* Schedule the loose reference for pruning if requested. */ if ((flags & PACK_REFS_PRUNE)) { @@@ -1577,69 -1129,15 +1130,15 @@@ if (ok != ITER_DONE) die("error while iterating over references"); - if (commit_packed_refs(refs)) - die_errno("unable to overwrite old ref-pack file"); + if (commit_packed_refs(refs->packed_ref_store, &err)) + die("unable to overwrite old ref-pack file: %s", err.buf); + packed_refs_unlock(refs->packed_ref_store); prune_refs(refs, refs_to_prune); + strbuf_release(&err); return 0; } - /* - * Rewrite the packed-refs file, omitting any refs listed in - * 'refnames'. On error, leave packed-refs unchanged, write an error - * message to 'err', and return a nonzero value. - * - * The refs in 'refnames' needn't be sorted. `err` must not be NULL. - */ - static int repack_without_refs(struct files_ref_store *refs, - struct string_list *refnames, struct strbuf *err) - { - struct ref_dir *packed; - struct string_list_item *refname; - int ret, needs_repacking = 0, removed = 0; - - files_assert_main_repository(refs, "repack_without_refs"); - assert(err); - - /* Look for a packed ref */ - for_each_string_list_item(refname, refnames) { - if (get_packed_ref(refs, refname->string)) { - needs_repacking = 1; - break; - } - } - - /* Avoid locking if we have nothing to do */ - if (!needs_repacking) - return 0; /* no refname exists in packed refs */ - - if (lock_packed_refs(refs, 0)) { - unable_to_lock_message(files_packed_refs_path(refs), errno, err); - return -1; - } - packed = get_packed_refs(refs); - - /* Remove refnames from the cache */ - for_each_string_list_item(refname, refnames) - if (remove_entry_from_dir(packed, refname->string) != -1) - removed = 1; - if (!removed) { - /* - * All packed entries disappeared while we were - * acquiring the lock. - */ - rollback_packed_refs(refs); - return 0; - } - - /* Write what remains */ - ret = commit_packed_refs(refs); - if (ret) - strbuf_addf(err, "unable to overwrite old ref-pack file: %s", - strerror(errno)); - return ret; - } - static int files_delete_refs(struct ref_store *ref_store, const char *msg, struct string_list *refnames, unsigned int flags) { @@@ -1651,24 -1149,16 +1150,16 @@@ if (!refnames->nr) return 0; - result = repack_without_refs(refs, refnames, &err); - if (result) { - /* - * If we failed to rewrite the packed-refs file, then - * it is unsafe to try to remove loose refs, because - * doing so might expose an obsolete packed value for - * a reference that might even point at an object that - * has been garbage collected. - */ - if (refnames->nr == 1) - error(_("could not delete reference %s: %s"), - refnames->items[0].string, err.buf); - else - error(_("could not delete references: %s"), err.buf); + if (packed_refs_lock(refs->packed_ref_store, 0, &err)) + goto error; - goto out; + if (repack_without_refs(refs->packed_ref_store, refnames, &err)) { + packed_refs_unlock(refs->packed_ref_store); + goto error; } + packed_refs_unlock(refs->packed_ref_store); + for (i = 0; i < refnames->nr; i++) { const char *refname = refnames->items[i].string; @@@ -1676,9 -1166,24 +1167,24 @@@ result |= error(_("could not remove reference %s"), refname); } - out: strbuf_release(&err); return result; + + error: + /* + * If we failed to rewrite the packed-refs file, then it is + * unsafe to try to remove loose refs, because doing so might + * expose an obsolete packed value for a reference that might + * even point at an object that has been garbage collected. + */ + if (refnames->nr == 1) + error(_("could not delete reference %s: %s"), + refnames->items[0].string, err.buf); + else + error(_("could not delete references: %s"), err.buf); + + strbuf_release(&err); + return -1; } /* @@@ -2959,7 -2464,8 +2465,7 @@@ static int files_transaction_prepare(st head_oid.hash, &head_type); if (head_ref && !(head_type & REF_ISSYMREF)) { - free(head_ref); - head_ref = NULL; + FREE_AND_NULL(head_ref); } /* @@@ -3070,11 -2576,19 +2576,19 @@@ static int files_transaction_finish(str } } - if (repack_without_refs(refs, &refs_to_delete, err)) { + if (packed_refs_lock(refs->packed_ref_store, 0, err)) { ret = TRANSACTION_GENERIC_ERROR; goto cleanup; } + if (repack_without_refs(refs->packed_ref_store, &refs_to_delete, err)) { + ret = TRANSACTION_GENERIC_ERROR; + packed_refs_unlock(refs->packed_ref_store); + goto cleanup; + } + + packed_refs_unlock(refs->packed_ref_store); + /* Delete the reflogs of any references that were deleted: */ for_each_string_list_item(ref_to_delete, &refs_to_delete) { strbuf_reset(&sb); @@@ -3181,9 -2695,7 +2695,7 @@@ static int files_initial_transaction_co } } - if (lock_packed_refs(refs, 0)) { - strbuf_addf(err, "unable to lock packed-refs file: %s", - strerror(errno)); + if (packed_refs_lock(refs->packed_ref_store, 0, err)) { ret = TRANSACTION_GENERIC_ERROR; goto cleanup; } @@@ -3193,18 -2705,17 +2705,17 @@@ if ((update->flags & REF_HAVE_NEW) && !is_null_oid(&update->new_oid)) - add_packed_ref(refs, update->refname, + add_packed_ref(refs->packed_ref_store, update->refname, &update->new_oid); } - if (commit_packed_refs(refs)) { - strbuf_addf(err, "unable to commit packed-refs file: %s", - strerror(errno)); + if (commit_packed_refs(refs->packed_ref_store, err)) { ret = TRANSACTION_GENERIC_ERROR; goto cleanup; } cleanup: + packed_refs_unlock(refs->packed_ref_store); transaction->state = REF_TRANSACTION_CLOSED; string_list_clear(&affected_refnames, 0); return ret; diff --combined refs/packed-backend.c index 0000000000,59e7d1a509..412c85034f mode 000000,100644..100644 --- a/refs/packed-backend.c +++ b/refs/packed-backend.c @@@ -1,0 -1,884 +1,885 @@@ + #include "../cache.h" ++#include "../config.h" + #include "../refs.h" + #include "refs-internal.h" + #include "ref-cache.h" + #include "packed-backend.h" + #include "../iterator.h" + #include "../lockfile.h" + + struct packed_ref_cache { + struct ref_cache *cache; + + /* + * Count of references to the data structure in this instance, + * including the pointer from files_ref_store::packed if any. + * The data will not be freed as long as the reference count + * is nonzero. + */ + unsigned int referrers; + + /* The metadata from when this packed-refs cache was read */ + struct stat_validity validity; + }; + + /* + * Increment the reference count of *packed_refs. + */ + static void acquire_packed_ref_cache(struct packed_ref_cache *packed_refs) + { + packed_refs->referrers++; + } + + /* + * Decrease the reference count of *packed_refs. If it goes to zero, + * free *packed_refs and return true; otherwise return false. + */ + static int release_packed_ref_cache(struct packed_ref_cache *packed_refs) + { + if (!--packed_refs->referrers) { + free_ref_cache(packed_refs->cache); + stat_validity_clear(&packed_refs->validity); + free(packed_refs); + return 1; + } else { + return 0; + } + } + + /* + * A container for `packed-refs`-related data. It is not (yet) a + * `ref_store`. + */ + struct packed_ref_store { + struct ref_store base; + + unsigned int store_flags; + + /* The path of the "packed-refs" file: */ + char *path; + + /* + * A cache of the values read from the `packed-refs` file, if + * it might still be current; otherwise, NULL. + */ + struct packed_ref_cache *cache; + + /* + * Lock used for the "packed-refs" file. Note that this (and + * thus the enclosing `packed_ref_store`) must not be freed. + */ + struct lock_file lock; + + /* + * Temporary file used when rewriting new contents to the + * "packed-refs" file. Note that this (and thus the enclosing + * `packed_ref_store`) must not be freed. + */ + struct tempfile tempfile; + }; + + struct ref_store *packed_ref_store_create(const char *path, + unsigned int store_flags) + { + struct packed_ref_store *refs = xcalloc(1, sizeof(*refs)); + struct ref_store *ref_store = (struct ref_store *)refs; + + base_ref_store_init(ref_store, &refs_be_packed); + refs->store_flags = store_flags; + + refs->path = xstrdup(path); + return ref_store; + } + + /* + * Die if refs is not the main ref store. caller is used in any + * necessary error messages. + */ + static void packed_assert_main_repository(struct packed_ref_store *refs, + const char *caller) + { + if (refs->store_flags & REF_STORE_MAIN) + return; + + die("BUG: operation %s only allowed for main ref store", caller); + } + + /* + * Downcast `ref_store` to `packed_ref_store`. Die if `ref_store` is + * not a `packed_ref_store`. Also die if `packed_ref_store` doesn't + * support at least the flags specified in `required_flags`. `caller` + * is used in any necessary error messages. + */ + static struct packed_ref_store *packed_downcast(struct ref_store *ref_store, + unsigned int required_flags, + const char *caller) + { + struct packed_ref_store *refs; + + if (ref_store->be != &refs_be_packed) + die("BUG: ref_store is type \"%s\" not \"packed\" in %s", + ref_store->be->name, caller); + + refs = (struct packed_ref_store *)ref_store; + + if ((refs->store_flags & required_flags) != required_flags) + die("BUG: unallowed operation (%s), requires %x, has %x\n", + caller, required_flags, refs->store_flags); + + return refs; + } + + static void clear_packed_ref_cache(struct packed_ref_store *refs) + { + if (refs->cache) { + struct packed_ref_cache *cache = refs->cache; + + refs->cache = NULL; + release_packed_ref_cache(cache); + } + } + + /* The length of a peeled reference line in packed-refs, including EOL: */ + #define PEELED_LINE_LENGTH 42 + + /* + * Parse one line from a packed-refs file. Write the SHA1 to sha1. + * Return a pointer to the refname within the line (null-terminated), + * or NULL if there was a problem. + */ + static const char *parse_ref_line(struct strbuf *line, struct object_id *oid) + { + const char *ref; + + if (parse_oid_hex(line->buf, oid, &ref) < 0) + return NULL; + if (!isspace(*ref++)) + return NULL; + + if (isspace(*ref)) + return NULL; + + if (line->buf[line->len - 1] != '\n') + return NULL; + line->buf[--line->len] = 0; + + return ref; + } + + /* + * Read from `packed_refs_file` into a newly-allocated + * `packed_ref_cache` and return it. The return value will already + * have its reference count incremented. + * + * A comment line of the form "# pack-refs with: " may contain zero or + * more traits. We interpret the traits as follows: + * + * No traits: + * + * Probably no references are peeled. But if the file contains a + * peeled value for a reference, we will use it. + * + * peeled: + * + * References under "refs/tags/", if they *can* be peeled, *are* + * peeled in this file. References outside of "refs/tags/" are + * probably not peeled even if they could have been, but if we find + * a peeled value for such a reference we will use it. + * + * fully-peeled: + * + * All references in the file that can be peeled are peeled. + * Inversely (and this is more important), any references in the + * file for which no peeled value is recorded is not peelable. This + * trait should typically be written alongside "peeled" for + * compatibility with older clients, but we do not require it + * (i.e., "peeled" is a no-op if "fully-peeled" is set). + */ + static struct packed_ref_cache *read_packed_refs(const char *packed_refs_file) + { + FILE *f; + struct packed_ref_cache *packed_refs = xcalloc(1, sizeof(*packed_refs)); + struct ref_entry *last = NULL; + struct strbuf line = STRBUF_INIT; + enum { PEELED_NONE, PEELED_TAGS, PEELED_FULLY } peeled = PEELED_NONE; + struct ref_dir *dir; + + acquire_packed_ref_cache(packed_refs); + packed_refs->cache = create_ref_cache(NULL, NULL); + packed_refs->cache->root->flag &= ~REF_INCOMPLETE; + + f = fopen(packed_refs_file, "r"); + if (!f) { + if (errno == ENOENT) { + /* + * This is OK; it just means that no + * "packed-refs" file has been written yet, + * which is equivalent to it being empty. + */ + return packed_refs; + } else { + die_errno("couldn't read %s", packed_refs_file); + } + } + + stat_validity_update(&packed_refs->validity, fileno(f)); + + dir = get_ref_dir(packed_refs->cache->root); + while (strbuf_getwholeline(&line, f, '\n') != EOF) { + struct object_id oid; + const char *refname; + const char *traits; + + if (!line.len || line.buf[line.len - 1] != '\n') + die("unterminated line in %s: %s", packed_refs_file, line.buf); + + if (skip_prefix(line.buf, "# pack-refs with:", &traits)) { + if (strstr(traits, " fully-peeled ")) + peeled = PEELED_FULLY; + else if (strstr(traits, " peeled ")) + peeled = PEELED_TAGS; + /* perhaps other traits later as well */ + continue; + } + + refname = parse_ref_line(&line, &oid); + if (refname) { + int flag = REF_ISPACKED; + + if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) { + if (!refname_is_safe(refname)) + die("packed refname is dangerous: %s", refname); + oidclr(&oid); + flag |= REF_BAD_NAME | REF_ISBROKEN; + } + last = create_ref_entry(refname, &oid, flag); + if (peeled == PEELED_FULLY || + (peeled == PEELED_TAGS && starts_with(refname, "refs/tags/"))) + last->flag |= REF_KNOWS_PEELED; + add_ref_entry(dir, last); + } else if (last && + line.buf[0] == '^' && + line.len == PEELED_LINE_LENGTH && + line.buf[PEELED_LINE_LENGTH - 1] == '\n' && + !get_oid_hex(line.buf + 1, &oid)) { + oidcpy(&last->u.value.peeled, &oid); + /* + * Regardless of what the file header said, + * we definitely know the value of *this* + * reference: + */ + last->flag |= REF_KNOWS_PEELED; + } else { + strbuf_setlen(&line, line.len - 1); + die("unexpected line in %s: %s", packed_refs_file, line.buf); + } + } + + fclose(f); + strbuf_release(&line); + + return packed_refs; + } + + /* + * Check that the packed refs cache (if any) still reflects the + * contents of the file. If not, clear the cache. + */ + static void validate_packed_ref_cache(struct packed_ref_store *refs) + { + if (refs->cache && + !stat_validity_check(&refs->cache->validity, refs->path)) + clear_packed_ref_cache(refs); + } + + /* + * Get the packed_ref_cache for the specified packed_ref_store, + * creating and populating it if it hasn't been read before or if the + * file has been changed (according to its `validity` field) since it + * was last read. On the other hand, if we hold the lock, then assume + * that the file hasn't been changed out from under us, so skip the + * extra `stat()` call in `stat_validity_check()`. + */ + static struct packed_ref_cache *get_packed_ref_cache(struct packed_ref_store *refs) + { + if (!is_lock_file_locked(&refs->lock)) + validate_packed_ref_cache(refs); + + if (!refs->cache) + refs->cache = read_packed_refs(refs->path); + + return refs->cache; + } + + static struct ref_dir *get_packed_ref_dir(struct packed_ref_cache *packed_ref_cache) + { + return get_ref_dir(packed_ref_cache->cache->root); + } + + static struct ref_dir *get_packed_refs(struct packed_ref_store *refs) + { + return get_packed_ref_dir(get_packed_ref_cache(refs)); + } + + /* + * Add or overwrite a reference in the in-memory packed reference + * cache. This may only be called while the packed-refs file is locked + * (see packed_refs_lock()). To actually write the packed-refs file, + * call commit_packed_refs(). + */ + void add_packed_ref(struct ref_store *ref_store, + const char *refname, const struct object_id *oid) + { + struct packed_ref_store *refs = + packed_downcast(ref_store, REF_STORE_WRITE, + "add_packed_ref"); + struct ref_dir *packed_refs; + struct ref_entry *packed_entry; + + if (!is_lock_file_locked(&refs->lock)) + die("BUG: packed refs not locked"); + + if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) + die("Reference has invalid format: '%s'", refname); + + packed_refs = get_packed_refs(refs); + packed_entry = find_ref_entry(packed_refs, refname); + if (packed_entry) { + /* Overwrite the existing entry: */ + oidcpy(&packed_entry->u.value.oid, oid); + packed_entry->flag = REF_ISPACKED; + oidclr(&packed_entry->u.value.peeled); + } else { + packed_entry = create_ref_entry(refname, oid, REF_ISPACKED); + add_ref_entry(packed_refs, packed_entry); + } + } + + /* + * Return the ref_entry for the given refname from the packed + * references. If it does not exist, return NULL. + */ + static struct ref_entry *get_packed_ref(struct packed_ref_store *refs, + const char *refname) + { + return find_ref_entry(get_packed_refs(refs), refname); + } + + static int packed_read_raw_ref(struct ref_store *ref_store, + const char *refname, unsigned char *sha1, + struct strbuf *referent, unsigned int *type) + { + struct packed_ref_store *refs = + packed_downcast(ref_store, REF_STORE_READ, "read_raw_ref"); + + struct ref_entry *entry; + + *type = 0; + + entry = get_packed_ref(refs, refname); + if (!entry) { + errno = ENOENT; + return -1; + } + + hashcpy(sha1, entry->u.value.oid.hash); + *type = REF_ISPACKED; + return 0; + } + + static int packed_peel_ref(struct ref_store *ref_store, + const char *refname, unsigned char *sha1) + { + struct packed_ref_store *refs = + packed_downcast(ref_store, REF_STORE_READ | REF_STORE_ODB, + "peel_ref"); + struct ref_entry *r = get_packed_ref(refs, refname); + + if (!r || peel_entry(r, 0)) + return -1; + + hashcpy(sha1, r->u.value.peeled.hash); + return 0; + } + + struct packed_ref_iterator { + struct ref_iterator base; + + struct packed_ref_cache *cache; + struct ref_iterator *iter0; + unsigned int flags; + }; + + static int packed_ref_iterator_advance(struct ref_iterator *ref_iterator) + { + struct packed_ref_iterator *iter = + (struct packed_ref_iterator *)ref_iterator; + int ok; + + while ((ok = ref_iterator_advance(iter->iter0)) == ITER_OK) { + if (iter->flags & DO_FOR_EACH_PER_WORKTREE_ONLY && + ref_type(iter->iter0->refname) != REF_TYPE_PER_WORKTREE) + continue; + + if (!(iter->flags & DO_FOR_EACH_INCLUDE_BROKEN) && + !ref_resolves_to_object(iter->iter0->refname, + iter->iter0->oid, + iter->iter0->flags)) + continue; + + iter->base.refname = iter->iter0->refname; + iter->base.oid = iter->iter0->oid; + iter->base.flags = iter->iter0->flags; + return ITER_OK; + } + + iter->iter0 = NULL; + if (ref_iterator_abort(ref_iterator) != ITER_DONE) + ok = ITER_ERROR; + + return ok; + } + + static int packed_ref_iterator_peel(struct ref_iterator *ref_iterator, + struct object_id *peeled) + { + struct packed_ref_iterator *iter = + (struct packed_ref_iterator *)ref_iterator; + + return ref_iterator_peel(iter->iter0, peeled); + } + + static int packed_ref_iterator_abort(struct ref_iterator *ref_iterator) + { + struct packed_ref_iterator *iter = + (struct packed_ref_iterator *)ref_iterator; + int ok = ITER_DONE; + + if (iter->iter0) + ok = ref_iterator_abort(iter->iter0); + + release_packed_ref_cache(iter->cache); + base_ref_iterator_free(ref_iterator); + return ok; + } + + static struct ref_iterator_vtable packed_ref_iterator_vtable = { + packed_ref_iterator_advance, + packed_ref_iterator_peel, + packed_ref_iterator_abort + }; + + static struct ref_iterator *packed_ref_iterator_begin( + struct ref_store *ref_store, + const char *prefix, unsigned int flags) + { + struct packed_ref_store *refs; + struct packed_ref_iterator *iter; + struct ref_iterator *ref_iterator; + unsigned int required_flags = REF_STORE_READ; + + if (!(flags & DO_FOR_EACH_INCLUDE_BROKEN)) + required_flags |= REF_STORE_ODB; + refs = packed_downcast(ref_store, required_flags, "ref_iterator_begin"); + + iter = xcalloc(1, sizeof(*iter)); + ref_iterator = &iter->base; + base_ref_iterator_init(ref_iterator, &packed_ref_iterator_vtable); + + /* + * Note that get_packed_ref_cache() internally checks whether + * the packed-ref cache is up to date with what is on disk, + * and re-reads it if not. + */ + + iter->cache = get_packed_ref_cache(refs); + acquire_packed_ref_cache(iter->cache); + iter->iter0 = cache_ref_iterator_begin(iter->cache->cache, prefix, 0); + + iter->flags = flags; + + return ref_iterator; + } + + /* + * Write an entry to the packed-refs file for the specified refname. + * If peeled is non-NULL, write it as the entry's peeled value. On + * error, return a nonzero value and leave errno set at the value left + * by the failing call to `fprintf()`. + */ + static int write_packed_entry(FILE *fh, const char *refname, + const unsigned char *sha1, + const unsigned char *peeled) + { + if (fprintf(fh, "%s %s\n", sha1_to_hex(sha1), refname) < 0 || + (peeled && fprintf(fh, "^%s\n", sha1_to_hex(peeled)) < 0)) + return -1; + + return 0; + } + + int packed_refs_lock(struct ref_store *ref_store, int flags, struct strbuf *err) + { + struct packed_ref_store *refs = + packed_downcast(ref_store, REF_STORE_WRITE | REF_STORE_MAIN, + "packed_refs_lock"); + static int timeout_configured = 0; + static int timeout_value = 1000; + struct packed_ref_cache *packed_ref_cache; + + if (!timeout_configured) { + git_config_get_int("core.packedrefstimeout", &timeout_value); + timeout_configured = 1; + } + + /* + * Note that we close the lockfile immediately because we + * don't write new content to it, but rather to a separate + * tempfile. + */ + if (hold_lock_file_for_update_timeout( + &refs->lock, + refs->path, + flags, timeout_value) < 0) { + unable_to_lock_message(refs->path, errno, err); + return -1; + } + + if (close_lock_file(&refs->lock)) { + strbuf_addf(err, "unable to close %s: %s", refs->path, strerror(errno)); + return -1; + } + + /* + * Now that we hold the `packed-refs` lock, make sure that our + * cache matches the current version of the file. Normally + * `get_packed_ref_cache()` does that for us, but that + * function assumes that when the file is locked, any existing + * cache is still valid. We've just locked the file, but it + * might have changed the moment *before* we locked it. + */ + validate_packed_ref_cache(refs); + + packed_ref_cache = get_packed_ref_cache(refs); + /* Increment the reference count to prevent it from being freed: */ + acquire_packed_ref_cache(packed_ref_cache); + return 0; + } + + void packed_refs_unlock(struct ref_store *ref_store) + { + struct packed_ref_store *refs = packed_downcast( + ref_store, + REF_STORE_READ | REF_STORE_WRITE, + "packed_refs_unlock"); + + if (!is_lock_file_locked(&refs->lock)) + die("BUG: packed_refs_unlock() called when not locked"); + rollback_lock_file(&refs->lock); + release_packed_ref_cache(refs->cache); + } + + int packed_refs_is_locked(struct ref_store *ref_store) + { + struct packed_ref_store *refs = packed_downcast( + ref_store, + REF_STORE_READ | REF_STORE_WRITE, + "packed_refs_is_locked"); + + return is_lock_file_locked(&refs->lock); + } + + /* + * The packed-refs header line that we write out. Perhaps other + * traits will be added later. The trailing space is required. + */ + static const char PACKED_REFS_HEADER[] = + "# pack-refs with: peeled fully-peeled \n"; + + /* + * Write the current version of the packed refs cache from memory to + * disk. The packed-refs file must already be locked for writing (see + * packed_refs_lock()). Return zero on success. On errors, rollback + * the lockfile, write an error message to `err`, and return a nonzero + * value. + */ + int commit_packed_refs(struct ref_store *ref_store, struct strbuf *err) + { + struct packed_ref_store *refs = + packed_downcast(ref_store, REF_STORE_WRITE | REF_STORE_MAIN, + "commit_packed_refs"); + struct packed_ref_cache *packed_ref_cache = + get_packed_ref_cache(refs); + int ok; + int ret = -1; + struct strbuf sb = STRBUF_INIT; + FILE *out; + struct ref_iterator *iter; + char *packed_refs_path; + + if (!is_lock_file_locked(&refs->lock)) + die("BUG: commit_packed_refs() called when unlocked"); + + /* + * If packed-refs is a symlink, we want to overwrite the + * symlinked-to file, not the symlink itself. Also, put the + * staging file next to it: + */ + packed_refs_path = get_locked_file_path(&refs->lock); + strbuf_addf(&sb, "%s.new", packed_refs_path); + if (create_tempfile(&refs->tempfile, sb.buf) < 0) { + strbuf_addf(err, "unable to create file %s: %s", + sb.buf, strerror(errno)); + strbuf_release(&sb); + goto out; + } + strbuf_release(&sb); + + out = fdopen_tempfile(&refs->tempfile, "w"); + if (!out) { + strbuf_addf(err, "unable to fdopen packed-refs tempfile: %s", + strerror(errno)); + goto error; + } + + if (fprintf(out, "%s", PACKED_REFS_HEADER) < 0) { + strbuf_addf(err, "error writing to %s: %s", + get_tempfile_path(&refs->tempfile), strerror(errno)); + goto error; + } + + iter = cache_ref_iterator_begin(packed_ref_cache->cache, NULL, 0); + while ((ok = ref_iterator_advance(iter)) == ITER_OK) { + struct object_id peeled; + int peel_error = ref_iterator_peel(iter, &peeled); + + if (write_packed_entry(out, iter->refname, iter->oid->hash, + peel_error ? NULL : peeled.hash)) { + strbuf_addf(err, "error writing to %s: %s", + get_tempfile_path(&refs->tempfile), + strerror(errno)); + ref_iterator_abort(iter); + goto error; + } + } + + if (ok != ITER_DONE) { + strbuf_addf(err, "unable to rewrite packed-refs file: " + "error iterating over old contents"); + goto error; + } + + if (rename_tempfile(&refs->tempfile, packed_refs_path)) { + strbuf_addf(err, "error replacing %s: %s", + refs->path, strerror(errno)); + goto out; + } + + ret = 0; + goto out; + + error: + delete_tempfile(&refs->tempfile); + + out: + free(packed_refs_path); + return ret; + } + + /* + * Rewrite the packed-refs file, omitting any refs listed in + * 'refnames'. On error, leave packed-refs unchanged, write an error + * message to 'err', and return a nonzero value. The packed refs lock + * must be held when calling this function; it will still be held when + * the function returns. + * + * The refs in 'refnames' needn't be sorted. `err` must not be NULL. + */ + int repack_without_refs(struct ref_store *ref_store, + struct string_list *refnames, struct strbuf *err) + { + struct packed_ref_store *refs = + packed_downcast(ref_store, REF_STORE_WRITE | REF_STORE_MAIN, + "repack_without_refs"); + struct ref_dir *packed; + struct string_list_item *refname; + int needs_repacking = 0, removed = 0; + + packed_assert_main_repository(refs, "repack_without_refs"); + assert(err); + + if (!is_lock_file_locked(&refs->lock)) + die("BUG: repack_without_refs called without holding lock"); + + /* Look for a packed ref */ + for_each_string_list_item(refname, refnames) { + if (get_packed_ref(refs, refname->string)) { + needs_repacking = 1; + break; + } + } + + /* Avoid locking if we have nothing to do */ + if (!needs_repacking) + return 0; /* no refname exists in packed refs */ + + packed = get_packed_refs(refs); + + /* Remove refnames from the cache */ + for_each_string_list_item(refname, refnames) + if (remove_entry_from_dir(packed, refname->string) != -1) + removed = 1; + if (!removed) { + /* + * All packed entries disappeared while we were + * acquiring the lock. + */ + clear_packed_ref_cache(refs); + return 0; + } + + /* Write what remains */ + return commit_packed_refs(&refs->base, err); + } + + static int packed_init_db(struct ref_store *ref_store, struct strbuf *err) + { + /* Nothing to do. */ + return 0; + } + + static int packed_transaction_prepare(struct ref_store *ref_store, + struct ref_transaction *transaction, + struct strbuf *err) + { + die("BUG: not implemented yet"); + } + + static int packed_transaction_abort(struct ref_store *ref_store, + struct ref_transaction *transaction, + struct strbuf *err) + { + die("BUG: not implemented yet"); + } + + static int packed_transaction_finish(struct ref_store *ref_store, + struct ref_transaction *transaction, + struct strbuf *err) + { + die("BUG: not implemented yet"); + } + + static int packed_initial_transaction_commit(struct ref_store *ref_store, + struct ref_transaction *transaction, + struct strbuf *err) + { + return ref_transaction_commit(transaction, err); + } + + static int packed_delete_refs(struct ref_store *ref_store, const char *msg, + struct string_list *refnames, unsigned int flags) + { + die("BUG: not implemented yet"); + } + + static int packed_pack_refs(struct ref_store *ref_store, unsigned int flags) + { + /* + * Packed refs are already packed. It might be that loose refs + * are packed *into* a packed refs store, but that is done by + * updating the packed references via a transaction. + */ + return 0; + } + + static int packed_create_symref(struct ref_store *ref_store, + const char *refname, const char *target, + const char *logmsg) + { + die("BUG: packed reference store does not support symrefs"); + } + + static int packed_rename_ref(struct ref_store *ref_store, + const char *oldrefname, const char *newrefname, + const char *logmsg) + { + die("BUG: packed reference store does not support renaming references"); + } + + static struct ref_iterator *packed_reflog_iterator_begin(struct ref_store *ref_store) + { + return empty_ref_iterator_begin(); + } + + static int packed_for_each_reflog_ent(struct ref_store *ref_store, + const char *refname, + each_reflog_ent_fn fn, void *cb_data) + { + return 0; + } + + static int packed_for_each_reflog_ent_reverse(struct ref_store *ref_store, + const char *refname, + each_reflog_ent_fn fn, + void *cb_data) + { + return 0; + } + + static int packed_reflog_exists(struct ref_store *ref_store, + const char *refname) + { + return 0; + } + + static int packed_create_reflog(struct ref_store *ref_store, + const char *refname, int force_create, + struct strbuf *err) + { + die("BUG: packed reference store does not support reflogs"); + } + + static int packed_delete_reflog(struct ref_store *ref_store, + const char *refname) + { + return 0; + } + + static int packed_reflog_expire(struct ref_store *ref_store, + const char *refname, const unsigned char *sha1, + unsigned int flags, + reflog_expiry_prepare_fn prepare_fn, + reflog_expiry_should_prune_fn should_prune_fn, + reflog_expiry_cleanup_fn cleanup_fn, + void *policy_cb_data) + { + return 0; + } + + struct ref_storage_be refs_be_packed = { + NULL, + "packed", + packed_ref_store_create, + packed_init_db, + packed_transaction_prepare, + packed_transaction_finish, + packed_transaction_abort, + packed_initial_transaction_commit, + + packed_pack_refs, + packed_peel_ref, + packed_create_symref, + packed_delete_refs, + packed_rename_ref, + + packed_ref_iterator_begin, + packed_read_raw_ref, + + packed_reflog_iterator_begin, + packed_for_each_reflog_ent, + packed_for_each_reflog_ent_reverse, + packed_reflog_exists, + packed_create_reflog, + packed_delete_reflog, + packed_reflog_expire + };