diff options
Diffstat (limited to 'refs.c')
| -rw-r--r-- | refs.c | 374 |
1 files changed, 249 insertions, 125 deletions
@@ -142,6 +142,8 @@ static int do_for_each_ref(const char *base, int (*fn)(const char *path, const u namelen = strlen(de->d_name); if (namelen > 255) continue; + if (namelen>5 && !strcmp(de->d_name+namelen-5,".lock")) + continue; memcpy(path + baselen, de->d_name, namelen+1); if (stat(git_path("%s", path), &st) < 0) continue; @@ -198,26 +200,6 @@ int for_each_remote_ref(int (*fn)(const char *path, const unsigned char *sha1)) return do_for_each_ref("refs/remotes", fn, 13); } -static char *ref_file_name(const char *ref) -{ - char *base = get_refs_directory(); - int baselen = strlen(base); - int reflen = strlen(ref); - char *ret = xmalloc(baselen + 2 + reflen); - sprintf(ret, "%s/%s", base, ref); - return ret; -} - -static char *ref_lock_file_name(const char *ref) -{ - char *base = get_refs_directory(); - int baselen = strlen(base); - int reflen = strlen(ref); - char *ret = xmalloc(baselen + 7 + reflen); - sprintf(ret, "%s/%s.lock", base, ref); - return ret; -} - int get_ref_sha1(const char *ref, unsigned char *sha1) { if (check_ref_format(ref)) @@ -225,94 +207,6 @@ int get_ref_sha1(const char *ref, unsigned char *sha1) return read_ref(git_path("refs/%s", ref), sha1); } -static int lock_ref_file(const char *filename, const char *lock_filename, - const unsigned char *old_sha1) -{ - int fd = open(lock_filename, O_WRONLY | O_CREAT | O_EXCL, 0666); - unsigned char current_sha1[20]; - int retval; - if (fd < 0) { - return error("Couldn't open lock file for %s: %s", - filename, strerror(errno)); - } - retval = read_ref(filename, current_sha1); - if (old_sha1) { - if (retval) { - close(fd); - unlink(lock_filename); - return error("Could not read the current value of %s", - filename); - } - if (memcmp(current_sha1, old_sha1, 20)) { - close(fd); - unlink(lock_filename); - error("The current value of %s is %s", - filename, sha1_to_hex(current_sha1)); - return error("Expected %s", - sha1_to_hex(old_sha1)); - } - } else { - if (!retval) { - close(fd); - unlink(lock_filename); - return error("Unexpectedly found a value of %s for %s", - sha1_to_hex(current_sha1), filename); - } - } - return fd; -} - -int lock_ref_sha1(const char *ref, const unsigned char *old_sha1) -{ - char *filename; - char *lock_filename; - int retval; - if (check_ref_format(ref)) - return -1; - filename = ref_file_name(ref); - lock_filename = ref_lock_file_name(ref); - retval = lock_ref_file(filename, lock_filename, old_sha1); - free(filename); - free(lock_filename); - return retval; -} - -static int write_ref_file(const char *filename, - const char *lock_filename, int fd, - const unsigned char *sha1) -{ - char *hex = sha1_to_hex(sha1); - char term = '\n'; - if (write(fd, hex, 40) < 40 || - write(fd, &term, 1) < 1) { - error("Couldn't write %s", filename); - close(fd); - return -1; - } - close(fd); - rename(lock_filename, filename); - return 0; -} - -int write_ref_sha1(const char *ref, int fd, const unsigned char *sha1) -{ - char *filename; - char *lock_filename; - int retval; - if (fd < 0) - return -1; - if (check_ref_format(ref)) - return -1; - filename = ref_file_name(ref); - lock_filename = ref_lock_file_name(ref); - if (safe_create_leading_directories(filename)) - die("unable to create leading directory for %s", filename); - retval = write_ref_file(filename, lock_filename, fd, sha1); - free(filename); - free(lock_filename); - return retval; -} - /* * Make sure "ref" is something reasonable to have under ".git/refs/"; * We do not like it if: @@ -365,25 +259,255 @@ int check_ref_format(const char *ref) } } -int write_ref_sha1_unlocked(const char *ref, const unsigned char *sha1) +static struct ref_lock* verify_lock(struct ref_lock *lock, + const unsigned char *old_sha1, int mustexist) +{ + char buf[40]; + int nr, fd = open(lock->ref_file, O_RDONLY); + if (fd < 0 && (mustexist || errno != ENOENT)) { + error("Can't verify ref %s", lock->ref_file); + unlock_ref(lock); + return NULL; + } + nr = read(fd, buf, 40); + close(fd); + if (nr != 40 || get_sha1_hex(buf, lock->old_sha1) < 0) { + error("Can't verify ref %s", lock->ref_file); + unlock_ref(lock); + return NULL; + } + if (memcmp(lock->old_sha1, old_sha1, 20)) { + error("Ref %s is at %s but expected %s", lock->ref_file, + sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1)); + unlock_ref(lock); + return NULL; + } + return lock; +} + +static struct ref_lock* lock_ref_sha1_basic(const char *path, + int plen, + const unsigned char *old_sha1, int mustexist) +{ + struct ref_lock *lock; + struct stat st; + + lock = xcalloc(1, sizeof(struct ref_lock)); + lock->lock_fd = -1; + + plen = strlen(path) - plen; + path = resolve_ref(path, lock->old_sha1, mustexist); + if (!path) { + unlock_ref(lock); + return NULL; + } + + lock->ref_file = strdup(path); + lock->lock_file = strdup(mkpath("%s.lock", lock->ref_file)); + lock->log_file = strdup(git_path("logs/%s", lock->ref_file + plen)); + lock->force_write = lstat(lock->ref_file, &st) && errno == ENOENT; + + if (safe_create_leading_directories(lock->lock_file)) + die("unable to create directory for %s", lock->lock_file); + lock->lock_fd = open(lock->lock_file, + O_WRONLY | O_CREAT | O_EXCL, 0666); + if (lock->lock_fd < 0) { + error("Couldn't open lock file %s: %s", + lock->lock_file, strerror(errno)); + unlock_ref(lock); + return NULL; + } + + return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock; +} + +struct ref_lock* lock_ref_sha1(const char *ref, + const unsigned char *old_sha1, int mustexist) { - char *filename; - char *lock_filename; - int fd; - int retval; if (check_ref_format(ref)) + return NULL; + return lock_ref_sha1_basic(git_path("refs/%s", ref), + 5 + strlen(ref), old_sha1, mustexist); +} + +struct ref_lock* lock_any_ref_for_update(const char *ref, + const unsigned char *old_sha1, int mustexist) +{ + return lock_ref_sha1_basic(git_path("%s", ref), + strlen(ref), old_sha1, mustexist); +} + +void unlock_ref (struct ref_lock *lock) +{ + if (lock->lock_fd >= 0) { + close(lock->lock_fd); + unlink(lock->lock_file); + } + if (lock->ref_file) + free(lock->ref_file); + if (lock->lock_file) + free(lock->lock_file); + if (lock->log_file) + free(lock->log_file); + free(lock); +} + +static int log_ref_write(struct ref_lock *lock, + const unsigned char *sha1, const char *msg) +{ + int logfd, written, oflags = O_APPEND | O_WRONLY; + unsigned maxlen, len; + char *logrec; + const char *comitter; + + if (log_all_ref_updates) { + if (safe_create_leading_directories(lock->log_file) < 0) + return error("unable to create directory for %s", + lock->log_file); + oflags |= O_CREAT; + } + + logfd = open(lock->log_file, oflags, 0666); + if (logfd < 0) { + if (!log_all_ref_updates && errno == ENOENT) + return 0; + return error("Unable to append to %s: %s", + lock->log_file, strerror(errno)); + } + + setup_ident(); + comitter = git_committer_info(1); + if (msg) { + maxlen = strlen(comitter) + strlen(msg) + 2*40 + 5; + logrec = xmalloc(maxlen); + len = snprintf(logrec, maxlen, "%s %s %s\t%s\n", + sha1_to_hex(lock->old_sha1), + sha1_to_hex(sha1), + comitter, + msg); + } else { + maxlen = strlen(comitter) + 2*40 + 4; + logrec = xmalloc(maxlen); + len = snprintf(logrec, maxlen, "%s %s %s\n", + sha1_to_hex(lock->old_sha1), + sha1_to_hex(sha1), + comitter); + } + written = len <= maxlen ? write(logfd, logrec, len) : -1; + free(logrec); + close(logfd); + if (written != len) + return error("Unable to append to %s", lock->log_file); + return 0; +} + +int write_ref_sha1(struct ref_lock *lock, + const unsigned char *sha1, const char *logmsg) +{ + static char term = '\n'; + + if (!lock) return -1; - filename = ref_file_name(ref); - lock_filename = ref_lock_file_name(ref); - if (safe_create_leading_directories(filename)) - die("unable to create leading directory for %s", filename); - fd = open(lock_filename, O_WRONLY | O_CREAT | O_EXCL, 0666); - if (fd < 0) { - error("Writing %s", lock_filename); - perror("Open"); + if (!lock->force_write && !memcmp(lock->old_sha1, sha1, 20)) { + unlock_ref(lock); + return 0; } - retval = write_ref_file(filename, lock_filename, fd, sha1); - free(filename); - free(lock_filename); - return retval; + if (write(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 || + write(lock->lock_fd, &term, 1) != 1 + || close(lock->lock_fd) < 0) { + error("Couldn't write %s", lock->lock_file); + unlock_ref(lock); + return -1; + } + if (log_ref_write(lock, sha1, logmsg) < 0) { + unlock_ref(lock); + return -1; + } + if (rename(lock->lock_file, lock->ref_file) < 0) { + error("Couldn't set %s", lock->ref_file); + unlock_ref(lock); + return -1; + } + lock->lock_fd = -1; + unlock_ref(lock); + return 0; +} + +int read_ref_at(const char *ref, unsigned long at_time, unsigned char *sha1) +{ + const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec; + char *tz_c; + int logfd, tz; + struct stat st; + unsigned long date; + unsigned char logged_sha1[20]; + + logfile = git_path("logs/%s", ref); + logfd = open(logfile, O_RDONLY, 0); + if (logfd < 0) + die("Unable to read log %s: %s", logfile, strerror(errno)); + fstat(logfd, &st); + if (!st.st_size) + die("Log %s is empty.", logfile); + logdata = mmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, logfd, 0); + close(logfd); + + lastrec = NULL; + rec = logend = logdata + st.st_size; + while (logdata < rec) { + if (logdata < rec && *(rec-1) == '\n') + rec--; + lastgt = NULL; + while (logdata < rec && *(rec-1) != '\n') { + rec--; + if (*rec == '>') + lastgt = rec; + } + if (!lastgt) + die("Log %s is corrupt.", logfile); + date = strtoul(lastgt + 1, &tz_c, 10); + if (date <= at_time) { + if (lastrec) { + if (get_sha1_hex(lastrec, logged_sha1)) + die("Log %s is corrupt.", logfile); + if (get_sha1_hex(rec + 41, sha1)) + die("Log %s is corrupt.", logfile); + if (memcmp(logged_sha1, sha1, 20)) { + tz = strtoul(tz_c, NULL, 10); + fprintf(stderr, + "warning: Log %s has gap after %s.\n", + logfile, show_rfc2822_date(date, tz)); + } + } else if (date == at_time) { + if (get_sha1_hex(rec + 41, sha1)) + die("Log %s is corrupt.", logfile); + } else { + if (get_sha1_hex(rec + 41, logged_sha1)) + die("Log %s is corrupt.", logfile); + if (memcmp(logged_sha1, sha1, 20)) { + tz = strtoul(tz_c, NULL, 10); + fprintf(stderr, + "warning: Log %s unexpectedly ended on %s.\n", + logfile, show_rfc2822_date(date, tz)); + } + } + munmap((void*)logdata, st.st_size); + return 0; + } + lastrec = rec; + } + + rec = logdata; + while (rec < logend && *rec != '>' && *rec != '\n') + rec++; + if (rec == logend || *rec == '\n') + die("Log %s is corrupt.", logfile); + date = strtoul(rec + 1, &tz_c, 10); + tz = strtoul(tz_c, NULL, 10); + if (get_sha1_hex(logdata, sha1)) + die("Log %s is corrupt.", logfile); + munmap((void*)logdata, st.st_size); + fprintf(stderr, "warning: Log %s only goes back to %s.\n", + logfile, show_rfc2822_date(date, tz)); + return 0; } |