#include "cache.h" #include "refs.h" #include "object.h" #include "tag.h" /* ISSYMREF=01 and ISPACKED=02 are public interfaces */ #define REF_KNOWS_PEELED 04 struct ref_list { struct ref_list *next; unsigned char flag; /* ISSYMREF? ISPACKED? */ unsigned char sha1[20]; unsigned char peeled[20]; char name[FLEX_ARRAY]; }; static const char *parse_ref_line(char *line, unsigned char *sha1) { /* * 42: the answer to everything. * * In this case, it happens to be the answer to * 40 (length of sha1 hex representation) * +1 (space in between hex and name) * +1 (newline at the end of the line) */ int len = strlen(line) - 42; if (len <= 0) return NULL; if (get_sha1_hex(line, sha1) < 0) return NULL; if (!isspace(line[40])) return NULL; line += 41; if (isspace(*line)) return NULL; if (line[len] != '\n') return NULL; line[len] = 0; return line; } static struct ref_list *add_ref(const char *name, const unsigned char *sha1, int flag, struct ref_list *list, struct ref_list **new_entry) { int len; struct ref_list **p = &list, *entry; /* Find the place to insert the ref into.. */ while ((entry = *p) != NULL) { int cmp = strcmp(entry->name, name); if (cmp > 0) break; /* Same as existing entry? */ if (!cmp) { if (new_entry) *new_entry = entry; return list; } p = &entry->next; } /* Allocate it and add it in.. */ len = strlen(name) + 1; entry = xmalloc(sizeof(struct ref_list) + len); hashcpy(entry->sha1, sha1); hashclr(entry->peeled); memcpy(entry->name, name, len); entry->flag = flag; entry->next = *p; *p = entry; if (new_entry) *new_entry = entry; return list; } /* * Future: need to be in "struct repository" * when doing a full libification. */ struct cached_refs { char did_loose; char did_packed; struct ref_list *loose; struct ref_list *packed; } cached_refs; static void free_ref_list(struct ref_list *list) { struct ref_list *next; for ( ; list; list = next) { next = list->next; free(list); } } static void invalidate_cached_refs(void) { struct cached_refs *ca = &cached_refs; if (ca->did_loose && ca->loose) free_ref_list(ca->loose); if (ca->did_packed && ca->packed) free_ref_list(ca->packed); ca->loose = ca->packed = NULL; ca->did_loose = ca->did_packed = 0; } static void read_packed_refs(FILE *f, struct cached_refs *cached_refs) { struct ref_list *list = NULL; struct ref_list *last = NULL; char refline[PATH_MAX]; int flag = REF_ISPACKED; while (fgets(refline, sizeof(refline), f)) { unsigned char sha1[20]; const char *name; static const char header[] = "# pack-refs with:"; if (!strncmp(refline, header, sizeof(header)-1)) { const char *traits = refline + sizeof(header) - 1; if (strstr(traits, " peeled ")) flag |= REF_KNOWS_PEELED; /* perhaps other traits later as well */ continue; } name = parse_ref_line(refline, sha1); if (name) { list = add_ref(name, sha1, flag, list, &last); continue; } if (last && refline[0] == '^' && strlen(refline) == 42 && refline[41] == '\n' && !get_sha1_hex(refline + 1, sha1)) hashcpy(last->peeled, sha1); } cached_refs->packed = list; } static struct ref_list *get_packed_refs(void) { if (!cached_refs.did_packed) { FILE *f = fopen(git_path("packed-refs"), "r"); cached_refs.packed = NULL; if (f) { read_packed_refs(f, &cached_refs); fclose(f); } cached_refs.did_packed = 1; } return cached_refs.packed; } static struct ref_list *get_ref_dir(const char *base, struct ref_list *list) { DIR *dir = opendir(git_path("%s", base)); if (dir) { struct dirent *de; int baselen = strlen(base); char *ref = xmalloc(baselen + 257); memcpy(ref, base, baselen); if (baselen && base[baselen-1] != '/') ref[baselen++] = '/'; while ((de = readdir(dir)) != NULL) { unsigned char sha1[20]; struct stat st; int flag; int namelen; if (de->d_name[0] == '.') continue; namelen = strlen(de->d_name); if (namelen > 255) continue; if (has_extension(de->d_name, ".lock")) continue; memcpy(ref + baselen, de->d_name, namelen+1); if (stat(git_path("%s", ref), &st) < 0) continue; if (S_ISDIR(st.st_mode)) { list = get_ref_dir(ref, list); continue; } if (!resolve_ref(ref, sha1, 1, &flag)) { error("%s points nowhere!", ref); continue; } list = add_ref(ref, sha1, flag, list, NULL); } free(ref); closedir(dir); } return list; } static struct ref_list *get_loose_refs(void) { if (!cached_refs.did_loose) { cached_refs.loose = get_ref_dir("refs", NULL); cached_refs.did_loose = 1; } return cached_refs.loose; } /* We allow "recursive" symbolic refs. Only within reason, though */ #define MAXDEPTH 5 const char *resolve_ref(const char *ref, unsigned char *sha1, int reading, int *flag) { int depth = MAXDEPTH, len; char buffer[256]; static char ref_buffer[256]; if (flag) *flag = 0; for (;;) { const char *path = git_path("%s", ref); struct stat st; char *buf; int fd; if (--depth < 0) return NULL; /* Special case: non-existing file. * Not having the refs/heads/new-branch is OK * if we are writing into it, so is .git/HEAD * that points at refs/heads/master still to be * born. It is NOT OK if we are resolving for * reading. */ if (lstat(path, &st) < 0) { struct ref_list *list = get_packed_refs(); while (list) { if (!strcmp(ref, list->name)) { hashcpy(sha1, list->sha1); if (flag) *flag |= REF_ISPACKED; return ref; } list = list->next; } if (reading || errno != ENOENT) return NULL; hashclr(sha1); return ref; } /* Follow "normalized" - ie "refs/.." symlinks by hand */ if (S_ISLNK(st.st_mode)) { len = readlink(path, buffer, sizeof(buffer)-1); if (len >= 5 && !memcmp("refs/", buffer, 5)) { buffer[len] = 0; strcpy(ref_buffer, buffer); ref = ref_buffer; if (flag) *flag |= REF_ISSYMREF; continue; } } /* Is it a directory? */ if (S_ISDIR(st.st_mode)) { errno = EISDIR; return NULL; } /* * Anything else, just open it and try to use it as * a ref */ fd = open(path, O_RDONLY); if (fd < 0) return NULL; len = read_in_full(fd, buffer, sizeof(buffer)-1); close(fd); /* * Is it a symbolic ref? */ if (len < 4 || memcmp("ref:", buffer, 4)) break; buf = buffer + 4; len -= 4; while (len && isspace(*buf)) buf++, len--; while (len && isspace(buf[len-1])) len--; buf[len] = 0; memcpy(ref_buffer, buf, len + 1); ref = ref_buffer; if (flag) *flag |= REF_ISSYMREF; } if (len < 40 || get_sha1_hex(buffer, sha1)) return NULL; return ref; } int read_ref(const char *ref, unsigned char *sha1) { if (resolve_ref(ref, sha1, 1, NULL)) return 0; return -1; } static int do_one_ref(const char *base, each_ref_fn fn, int trim, void *cb_data, struct ref_list *entry) { if (strncmp(base, entry->name, trim)) return 0; if (is_null_sha1(entry->sha1)) return 0; if (!has_sha1_file(entry->sha1)) { error("%s does not point to a valid object!", entry->name); return 0; } return fn(entry->name + trim, entry->sha1, entry->flag, cb_data); } int peel_ref(const char *ref, unsigned char *sha1) { int flag; unsigned char base[20]; struct object *o; if (!resolve_ref(ref, base, 1, &flag)) return -1; if ((flag & REF_ISPACKED)) { struct ref_list *list = get_packed_refs(); while (list) { if (!strcmp(list->name, ref)) { if (list->flag & REF_KNOWS_PEELED) { hashcpy(sha1, list->peeled); return 0; } /* older pack-refs did not leave peeled ones */ break; } list = list->next; } } /* fallback - callers should not call this for unpacked refs */ o = parse_object(base); if (o->type == OBJ_TAG) { o = deref_tag(o, ref, 0); if (o) { hashcpy(sha1, o->sha1); return 0; } } return -1; } static int do_for_each_ref(const char *base, each_ref_fn fn, int trim, void *cb_data) { int retval; struct ref_list *packed = get_packed_refs(); struct ref_list *loose = get_loose_refs(); while (packed && loose) { struct ref_list *entry; int cmp = strcmp(packed->name, loose->name); if (!cmp) { packed = packed->next; continue; } if (cmp > 0) { entry = loose; loose = loose->next; } else { entry = packed; packed = packed->next; } retval = do_one_ref(base, fn, trim, cb_data, entry); if (retval) return retval; } for (packed = packed ? packed : loose; packed; packed = packed->next) { retval = do_one_ref(base, fn, trim, cb_data, packed); if (retval) return retval; } return 0; } int head_ref(each_ref_fn fn, void *cb_data) { unsigned char sha1[20]; int flag; if (resolve_ref("HEAD", sha1, 1, &flag)) return fn("HEAD", sha1, flag, cb_data); return 0; } int for_each_ref(each_ref_fn fn, void *cb_data) { return do_for_each_ref("refs/", fn, 0, cb_data); } int for_each_tag_ref(each_ref_fn fn, void *cb_data) { return do_for_each_ref("refs/tags/", fn, 10, cb_data); } int for_each_branch_ref(each_ref_fn fn, void *cb_data) { return do_for_each_ref("refs/heads/", fn, 11, cb_data); } int for_each_remote_ref(each_ref_fn fn, void *cb_data) { return do_for_each_ref("refs/remotes/", fn, 13, cb_data); } /* NEEDSWORK: This is only used by ssh-upload and it should go; the * caller should do resolve_ref or read_ref like everybody else. Or * maybe everybody else should use get_ref_sha1() instead of doing * read_ref(). */ int get_ref_sha1(const char *ref, unsigned char *sha1) { if (check_ref_format(ref)) return -1; return read_ref(mkpath("refs/%s", ref), sha1); } /* * Make sure "ref" is something reasonable to have under ".git/refs/"; * We do not like it if: * * - any path component of it begins with ".", or * - it has double dots "..", or * - it has ASCII control character, "~", "^", ":" or SP, anywhere, or * - it ends with a "/". */ static inline int bad_ref_char(int ch) { return (((unsigned) ch) <= ' ' || ch == '~' || ch == '^' || ch == ':' || /* 2.13 Pattern Matching Notation */ ch == '?' || ch == '*' || ch == '['); } int check_ref_format(const char *ref) { int ch, level; const char *cp = ref; level = 0; while (1) { while ((ch = *cp++) == '/') ; /* tolerate duplicated slashes */ if (!ch) return -1; /* should not end with slashes */ /* we are at the beginning of the path component */ if (ch == '.' || bad_ref_char(ch)) return -1; /* scan the rest of the path component */ while ((ch = *cp++) != 0) { if (bad_ref_char(ch)) return -1; if (ch == '/') break; if (ch == '.' && *cp == '.') return -1; } level++; if (!ch) { if (level < 2) return -2; /* at least of form "heads/blah" */ return 0; } } } static struct ref_lock *verify_lock(struct ref_lock *lock, const unsigned char *old_sha1, int mustexist) { if (!resolve_ref(lock->ref_name, lock->old_sha1, mustexist, NULL)) { error("Can't verify ref %s", lock->ref_name); unlock_ref(lock); return NULL; } if (hashcmp(lock->old_sha1, old_sha1)) { error("Ref %s is at %s but expected %s", lock->ref_name, sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1)); unlock_ref(lock); return NULL; } return lock; } static int remove_empty_dir_recursive(char *path, int len) { DIR *dir = opendir(path); struct dirent *e; int ret = 0; if (!dir) return -1; if (path[len-1] != '/') path[len++] = '/'; while ((e = readdir(dir)) != NULL) { struct stat st; int namlen; if ((e->d_name[0] == '.') && ((e->d_name[1] == 0) || ((e->d_name[1] == '.') && e->d_name[2] == 0))) continue; /* "." and ".." */ namlen = strlen(e->d_name); if ((len + namlen < PATH_MAX) && strcpy(path + len, e->d_name) && !lstat(path, &st) && S_ISDIR(st.st_mode) && !remove_empty_dir_recursive(path, len + namlen)) continue; /* happy */ /* path too long, stat fails, or non-directory still exists */ ret = -1; break; } closedir(dir); if (!ret) { path[len] = 0; ret = rmdir(path); } return ret; } static int remove_empty_directories(char *file) { /* we want to create a file but there is a directory there; * if that is an empty directory (or a directory that contains * only empty directories), remove them. */ char path[PATH_MAX]; int len = strlen(file); if (len >= PATH_MAX) /* path too long ;-) */ return -1; strcpy(path, file); return remove_empty_dir_recursive(path, len); } static int is_refname_available(const char *ref, const char *oldref, struct ref_list *list, int quiet) { int namlen = strlen(ref); /* e.g. 'foo/bar' */ while (list) { /* list->name could be 'foo' or 'foo/bar/baz' */ if (!oldref || strcmp(oldref, list->name)) { int len = strlen(list->name); int cmplen = (namlen < len) ? namlen : len; const char *lead = (namlen < len) ? list->name : ref; if (!strncmp(ref, list->name, cmplen) && lead[cmplen] == '/') { if (!quiet) error("'%s' exists; cannot create '%s'", list->name, ref); return 0; } } list = list->next; } return 1; } static struct ref_lock *lock_ref_sha1_basic(const char *ref, const unsigned char *old_sha1, int *flag) { char *ref_file; const char *orig_ref = ref; struct ref_lock *lock; struct stat st; int last_errno = 0; int mustexist = (old_sha1 && !is_null_sha1(old_sha1)); lock = xcalloc(1, sizeof(struct ref_lock)); lock->lock_fd = -1; ref = resolve_ref(ref, lock->old_sha1, mustexist, flag); if (!ref && errno == EISDIR) { /* we are trying to lock foo but we used to * have foo/bar which now does not exist; * it is normal for the empty directory 'foo' * to remain. */ ref_file = git_path("%s", orig_ref); if (remove_empty_directories(ref_file)) { last_errno = errno; error("there are still refs under '%s'", orig_ref); goto error_return; } ref = resolve_ref(orig_ref, lock->old_sha1, mustexist, flag); } if (!ref) { last_errno = errno; error("unable to resolve reference %s: %s", orig_ref, strerror(errno)); goto error_return; } /* When the ref did not exist and we are creating it, * make sure there is no existing ref that is packed * whose name begins with our refname, nor a ref whose * name is a proper prefix of our refname. */ if (is_null_sha1(lock->old_sha1) && !is_refname_available(ref, NULL, get_packed_refs(), 0)) goto error_return; lock->lk = xcalloc(1, sizeof(struct lock_file)); lock->ref_name = xstrdup(ref); lock->orig_ref_name = xstrdup(orig_ref); ref_file = git_path("%s", ref); lock->force_write = lstat(ref_file, &st) && errno == ENOENT; if (safe_create_leading_directories(ref_file)) { last_errno = errno; error("unable to create directory for %s", ref_file); goto error_return; } lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, 1); return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock; error_return: unlock_ref(lock); errno = last_errno; return NULL; } struct ref_lock *lock_ref_sha1(const char *ref, const unsigned char *old_sha1) { char refpath[PATH_MAX]; if (check_ref_format(ref)) return NULL; strcpy(refpath, mkpath("refs/%s", ref)); return lock_ref_sha1_basic(refpath, old_sha1, NULL); } struct ref_lock *lock_any_ref_for_update(const char *ref, const unsigned char *old_sha1) { if (check_ref_format(ref) == -1) return NULL; return lock_ref_sha1_basic(ref, old_sha1, NULL); } static struct lock_file packlock; static int repack_without_ref(const char *refname) { struct ref_list *list, *packed_ref_list; int fd; int found = 0; packed_ref_list = get_packed_refs(); for (list = packed_ref_list; list; list = list->next) { if (!strcmp(refname, list->name)) { found = 1; break; } } if (!found) return 0; fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0); if (fd < 0) return error("cannot delete '%s' from packed refs", refname); for (list = packed_ref_list; list; list = list->next) { char line[PATH_MAX + 100]; int len; if (!strcmp(refname, list->name)) continue; len = snprintf(line, sizeof(line), "%s %s\n", sha1_to_hex(list->sha1), list->name); /* this should not happen but just being defensive */ if (len > sizeof(line)) die("too long a refname '%s'", list->name); write_or_die(fd, line, len); } return commit_lock_file(&packlock); } int delete_ref(const char *refname, unsigned char *sha1) { struct ref_lock *lock; int err, i, ret = 0, flag = 0; lock = lock_ref_sha1_basic(refname, sha1, &flag); if (!lock) return 1; if (!(flag & REF_ISPACKED)) { /* loose */ i = strlen(lock->lk->filename) - 5; /* .lock */ lock->lk->filename[i] = 0; err = unlink(lock->lk->filename); if (err) { ret = 1; error("unlink(%s) failed: %s", lock->lk->filename, strerror(errno)); } lock->lk->filename[i] = '.'; } /* removing the loose one could have resurrected an earlier * packed one. Also, if it was not loose we need to repack * without it. */ ret |= repack_without_ref(refname); err = unlink(git_path("logs/%s", lock->ref_name)); if (err && errno != ENOENT) fprintf(stderr, "warning: unlink(%s) failed: %s", git_path("logs/%s", lock->ref_name), strerror(errno)); invalidate_cached_refs(); unlock_ref(lock); return ret; } int rename_ref(const char *oldref, const char *newref, const char *logmsg) { static const char renamed_ref[] = "RENAMED-REF"; unsigned char sha1[20], orig_sha1[20]; int flag = 0, logmoved = 0; struct ref_lock *lock; struct stat loginfo; int log = !lstat(git_path("logs/%s", oldref), &loginfo); if (S_ISLNK(loginfo.st_mode)) return error("reflog for %s is a symlink", oldref); if (!resolve_ref(oldref, orig_sha1, 1, &flag)) return error("refname %s not found", oldref); if (!is_refname_available(newref, oldref, get_packed_refs(), 0)) return 1; if (!is_refname_available(newref, oldref, get_loose_refs(), 0)) return 1; lock = lock_ref_sha1_basic(renamed_ref, NULL, NULL); if (!lock) return error("unable to lock %s", renamed_ref); lock->force_write = 1; if (write_ref_sha1(lock, orig_sha1, logmsg)) return error("unable to save current sha1 in %s", renamed_ref); if (log && rename(git_path("logs/%s", oldref), git_path("tmp-renamed-log"))) return error("unable to move logfile logs/%s to tmp-renamed-log: %s", oldref, strerror(errno)); if (delete_ref(oldref, orig_sha1)) { error("unable to delete old %s", oldref); goto rollback; } if (resolve_ref(newref, sha1, 1, &flag) && delete_ref(newref, sha1)) { if (errno==EISDIR) { if (remove_empty_directories(git_path("%s", newref))) { error("Directory not empty: %s", newref); goto rollback; } } else { error("unable to delete existing %s", newref); goto rollback; } } if (log && safe_create_leading_directories(git_path("logs/%s", newref))) { error("unable to create directory for %s", newref); goto rollback; } retry: if (log && rename(git_path("tmp-renamed-log"), git_path("logs/%s", newref))) { if (errno==EISDIR || errno==ENOTDIR) { /* * rename(a, b) when b is an existing * directory ought to result in ISDIR, but * Solaris 5.8 gives ENOTDIR. Sheesh. */ if (remove_empty_directories(git_path("logs/%s", newref))) { error("Directory not empty: logs/%s", newref); goto rollback; } goto retry; } else { error("unable to move logfile tmp-renamed-log to logs/%s: %s", newref, strerror(errno)); goto rollback; } } logmoved = log; lock = lock_ref_sha1_basic(newref, NULL, NULL); if (!lock) { error("unable to lock %s for update", newref); goto rollback; } lock->force_write = 1; hashcpy(lock->old_sha1, orig_sha1); if (write_ref_sha1(lock, orig_sha1, logmsg)) { error("unable to write current sha1 into %s", newref); goto rollback; } if (!prefixcmp(oldref, "refs/heads/") && !prefixcmp(newref, "refs/heads/")) { char oldsection[1024], newsection[1024]; snprintf(oldsection, 1024, "branch.%s", oldref + 11); snprintf(newsection, 1024, "branch.%s", newref + 11); if (git_config_rename_section(oldsection, newsection) < 0) return 1; } return 0; rollback: lock = lock_ref_sha1_basic(oldref, NULL, NULL); if (!lock) { error("unable to lock %s for rollback", oldref); goto rollbacklog; } lock->force_write = 1; flag = log_all_ref_updates; log_all_ref_updates = 0; if (write_ref_sha1(lock, orig_sha1, NULL)) error("unable to write current sha1 into %s", oldref); log_all_ref_updates = flag; rollbacklog: if (logmoved && rename(git_path("logs/%s", newref), git_path("logs/%s", oldref))) error("unable to restore logfile %s from %s: %s", oldref, newref, strerror(errno)); if (!logmoved && log && rename(git_path("tmp-renamed-log"), git_path("logs/%s", oldref))) error("unable to restore logfile %s from tmp-renamed-log: %s", oldref, strerror(errno)); return 1; } void unlock_ref(struct ref_lock *lock) { if (lock->lock_fd >= 0) { close(lock->lock_fd); /* Do not free lock->lk -- atexit() still looks at them */ if (lock->lk) rollback_lock_file(lock->lk); } free(lock->ref_name); free(lock->orig_ref_name); free(lock); } static int log_ref_write(const char *ref_name, const unsigned char *old_sha1, const unsigned char *new_sha1, const char *msg) { int logfd, written, oflags = O_APPEND | O_WRONLY; unsigned maxlen, len; int msglen; char *log_file, *logrec; const char *committer; if (log_all_ref_updates < 0) log_all_ref_updates = !is_bare_repository(); log_file = git_path("logs/%s", ref_name); if (log_all_ref_updates && (!prefixcmp(ref_name, "refs/heads/") || !prefixcmp(ref_name, "refs/remotes/") || !strcmp(ref_name, "HEAD"))) { if (safe_create_leading_directories(log_file) < 0) return error("unable to create directory for %s", log_file); oflags |= O_CREAT; } logfd = open(log_file, oflags, 0666); if (logfd < 0) { if (!(oflags & O_CREAT) && errno == ENOENT) return 0; if ((oflags & O_CREAT) && errno == EISDIR) { if (remove_empty_directories(log_file)) { return error("There are still logs under '%s'", log_file); } logfd = open(log_file, oflags, 0666); } if (logfd < 0) return error("Unable to append to %s: %s", log_file, strerror(errno)); } adjust_shared_perm(log_file); msglen = 0; if (msg) { /* clean up the message and make sure it is a single line */ for ( ; *msg; msg++) if (!isspace(*msg)) break; if (*msg) { const char *ep = strchr(msg, '\n'); if (ep) msglen = ep - msg; else msglen = strlen(msg); } } committer = git_committer_info(-1); maxlen = strlen(committer) + msglen + 100; logrec = xmalloc(maxlen); len = sprintf(logrec, "%s %s %s\n", sha1_to_hex(old_sha1), sha1_to_hex(new_sha1), committer); if (msglen) len += sprintf(logrec + len - 1, "\t%.*s\n", msglen, msg) - 1; written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1; free(logrec); close(logfd); if (written != len) return error("Unable to append to %s", 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; if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) { unlock_ref(lock); return 0; } if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 || write_in_full(lock->lock_fd, &term, 1) != 1 || close(lock->lock_fd) < 0) { error("Couldn't write %s", lock->lk->filename); unlock_ref(lock); return -1; } invalidate_cached_refs(); if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 || (strcmp(lock->ref_name, lock->orig_ref_name) && log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) { unlock_ref(lock); return -1; } if (commit_lock_file(lock->lk)) { error("Couldn't set %s", lock->ref_name); unlock_ref(lock); return -1; } lock->lock_fd = -1; unlock_ref(lock); return 0; } int create_symref(const char *ref_target, const char *refs_heads_master, const char *logmsg) { const char *lockpath; char ref[1000]; int fd, len, written; char *git_HEAD = xstrdup(git_path("%s", ref_target)); unsigned char old_sha1[20], new_sha1[20]; if (logmsg && read_ref(ref_target, old_sha1)) hashclr(old_sha1); if (safe_create_leading_directories(git_HEAD) < 0) return error("unable to create directory for %s", git_HEAD); #ifndef NO_SYMLINK_HEAD if (prefer_symlink_refs) { unlink(git_HEAD); if (!symlink(refs_heads_master, git_HEAD)) goto done; fprintf(stderr, "no symlink - falling back to symbolic ref\n"); } #endif len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master); if (sizeof(ref) <= len) { error("refname too long: %s", refs_heads_master); goto error_free_return; } lockpath = mkpath("%s.lock", git_HEAD); fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666); if (fd < 0) { error("Unable to open %s for writing", lockpath); goto error_free_return; } written = write_in_full(fd, ref, len); close(fd); if (written != len) { error("Unable to write to %s", lockpath); goto error_unlink_return; } if (rename(lockpath, git_HEAD) < 0) { error("Unable to create %s", git_HEAD); goto error_unlink_return; } if (adjust_shared_perm(git_HEAD)) { error("Unable to fix permissions on %s", lockpath); error_unlink_return: unlink(lockpath); error_free_return: free(git_HEAD); return -1; } #ifndef NO_SYMLINK_HEAD done: #endif if (logmsg && !read_ref(refs_heads_master, new_sha1)) log_ref_write(ref_target, old_sha1, new_sha1, logmsg); free(git_HEAD); return 0; } static char *ref_msg(const char *line, const char *endp) { const char *ep; char *msg; line += 82; for (ep = line; ep < endp && *ep != '\n'; ep++) ; msg = xmalloc(ep - line + 1); memcpy(msg, line, ep - line); msg[ep - line] = 0; return msg; } int read_ref_at(const char *ref, unsigned long at_time, int cnt, unsigned char *sha1, char **msg, unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt) { const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec; char *tz_c; int logfd, tz, reccnt = 0; struct stat st; unsigned long date; unsigned char logged_sha1[20]; void *log_mapped; size_t mapsz; 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); mapsz = xsize_t(st.st_size); log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0); logdata = log_mapped; close(logfd); lastrec = NULL; rec = logend = logdata + st.st_size; while (logdata < rec) { reccnt++; 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 || cnt == 0) { tz = strtoul(tz_c, NULL, 10); if (msg) *msg = ref_msg(rec, logend); if (cutoff_time) *cutoff_time = date; if (cutoff_tz) *cutoff_tz = tz; if (cutoff_cnt) *cutoff_cnt = reccnt - 1; 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 (hashcmp(logged_sha1, sha1)) { 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 (hashcmp(logged_sha1, sha1)) { fprintf(stderr, "warning: Log %s unexpectedly ended on %s.\n", logfile, show_rfc2822_date(date, tz)); } } munmap(log_mapped, mapsz); return 0; } lastrec = rec; if (cnt > 0) cnt--; } 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); if (msg) *msg = ref_msg(logdata, logend); munmap(log_mapped, mapsz); if (cutoff_time) *cutoff_time = date; if (cutoff_tz) *cutoff_tz = tz; if (cutoff_cnt) *cutoff_cnt = reccnt; return 1; } int for_each_reflog_ent(const char *ref, each_reflog_ent_fn fn, void *cb_data) { const char *logfile; FILE *logfp; char buf[1024]; int ret = 0; logfile = git_path("logs/%s", ref); logfp = fopen(logfile, "r"); if (!logfp) return -1; while (fgets(buf, sizeof(buf), logfp)) { unsigned char osha1[20], nsha1[20]; char *email_end, *message; unsigned long timestamp; int len, tz; /* old SP new SP name <email> SP time TAB msg LF */ len = strlen(buf); if (len < 83 || buf[len-1] != '\n' || get_sha1_hex(buf, osha1) || buf[40] != ' ' || get_sha1_hex(buf + 41, nsha1) || buf[81] != ' ' || !(email_end = strchr(buf + 82, '>')) || email_end[1] != ' ' || !(timestamp = strtoul(email_end + 2, &message, 10)) || !message || message[0] != ' ' || (message[1] != '+' && message[1] != '-') || !isdigit(message[2]) || !isdigit(message[3]) || !isdigit(message[4]) || !isdigit(message[5])) continue; /* corrupt? */ email_end[1] = '\0'; tz = strtol(message + 1, NULL, 10); if (message[6] != '\t') message += 6; else message += 7; ret = fn(osha1, nsha1, buf+82, timestamp, tz, message, cb_data); if (ret) break; } fclose(logfp); return ret; } static int do_for_each_reflog(const char *base, each_ref_fn fn, void *cb_data) { DIR *dir = opendir(git_path("logs/%s", base)); int retval = 0; if (dir) { struct dirent *de; int baselen = strlen(base); char *log = xmalloc(baselen + 257); memcpy(log, base, baselen); if (baselen && base[baselen-1] != '/') log[baselen++] = '/'; while ((de = readdir(dir)) != NULL) { struct stat st; int namelen; if (de->d_name[0] == '.') continue; namelen = strlen(de->d_name); if (namelen > 255) continue; if (has_extension(de->d_name, ".lock")) continue; memcpy(log + baselen, de->d_name, namelen+1); if (stat(git_path("logs/%s", log), &st) < 0) continue; if (S_ISDIR(st.st_mode)) { retval = do_for_each_reflog(log, fn, cb_data); } else { unsigned char sha1[20]; if (!resolve_ref(log, sha1, 0, NULL)) retval = error("bad ref for %s", log); else retval = fn(log, sha1, 0, cb_data); } if (retval) break; } free(log); closedir(dir); } else if (*base) return errno; return retval; } int for_each_reflog(each_ref_fn fn, void *cb_data) { return do_for_each_reflog("", fn, cb_data); }