#include "cache.h" #include "refs.h" #include "object.h" #include "tag.h" #include "dir.h" /* ISSYMREF=01 and ISPACKED=02 are public interfaces */ #define REF_KNOWS_PEELED 04 #define REF_BROKEN 010 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 *entry; /* 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 = list; if (new_entry) *new_entry = entry; return entry; } /* merge sort the ref list */ static struct ref_list *sort_ref_list(struct ref_list *list) { int psize, qsize, last_merge_count, cmp; struct ref_list *p, *q, *l, *e; struct ref_list *new_list = list; int k = 1; int merge_count = 0; if (!list) return list; do { last_merge_count = merge_count; merge_count = 0; psize = 0; p = new_list; q = new_list; new_list = NULL; l = NULL; while (p) { merge_count++; while (psize < k && q->next) { q = q->next; psize++; } qsize = k; while ((psize > 0) || (qsize > 0 && q)) { if (qsize == 0 || !q) { e = p; p = p->next; psize--; } else if (psize == 0) { e = q; q = q->next; qsize--; } else { cmp = strcmp(q->name, p->name); if (cmp < 0) { e = q; q = q->next; qsize--; } else if (cmp > 0) { e = p; p = p->next; psize--; } else { if (hashcmp(q->sha1, p->sha1)) die("Duplicated ref, and SHA1s don't match: %s", q->name); warning("Duplicated ref: %s", q->name); e = q; q = q->next; qsize--; free(e); e = p; p = p->next; psize--; } } e->next = NULL; if (l) l->next = e; if (!new_list) new_list = e; l = e; } p = q; }; k = k * 2; } while ((last_merge_count != merge_count) || (last_merge_count != 1)); return new_list; } /* * Future: need to be in "struct repository" * when doing a full libification. */ static struct cached_refs { char did_loose; char did_packed; struct ref_list *loose; struct ref_list *packed; } cached_refs, submodule_refs; static struct ref_list *current_ref; static struct ref_list *extra_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 = sort_ref_list(list); } void add_extra_ref(const char *name, const unsigned char *sha1, int flag) { extra_refs = add_ref(name, sha1, flag, extra_refs, NULL); } void clear_extra_refs(void) { free_ref_list(extra_refs); extra_refs = NULL; } static struct ref_list *get_packed_refs(const char *submodule) { const char *packed_refs_file; struct cached_refs *refs; if (submodule) { packed_refs_file = git_path_submodule(submodule, "packed-refs"); refs = &submodule_refs; free_ref_list(refs->packed); } else { packed_refs_file = git_path("packed-refs"); refs = &cached_refs; } if (!refs->did_packed || submodule) { FILE *f = fopen(packed_refs_file, "r"); refs->packed = NULL; if (f) { read_packed_refs(f, refs); fclose(f); } refs->did_packed = 1; } return refs->packed; } static struct ref_list *get_ref_dir(const char *submodule, const char *base, struct ref_list *list) { DIR *dir; const char *path; if (submodule) path = git_path_submodule(submodule, "%s", base); else path = git_path("%s", base); dir = opendir(path); 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; const char *refdir; 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); refdir = submodule ? git_path_submodule(submodule, "%s", ref) : git_path("%s", ref); if (stat(refdir, &st) < 0) continue; if (S_ISDIR(st.st_mode)) { list = get_ref_dir(submodule, ref, list); continue; } if (submodule) { hashclr(sha1); flag = 0; if (resolve_gitlink_ref(submodule, ref, sha1) < 0) { hashclr(sha1); flag |= REF_BROKEN; } } else if (!resolve_ref(ref, sha1, 1, &flag)) { hashclr(sha1); flag |= REF_BROKEN; } list = add_ref(ref, sha1, flag, list, NULL); } free(ref); closedir(dir); } return sort_ref_list(list); } struct warn_if_dangling_data { FILE *fp; const char *refname; const char *msg_fmt; }; static int warn_if_dangling_symref(const char *refname, const unsigned char *sha1, int flags, void *cb_data) { struct warn_if_dangling_data *d = cb_data; const char *resolves_to; unsigned char junk[20]; if (!(flags & REF_ISSYMREF)) return 0; resolves_to = resolve_ref(refname, junk, 0, NULL); if (!resolves_to || strcmp(resolves_to, d->refname)) return 0; fprintf(d->fp, d->msg_fmt, refname); return 0; } void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname) { struct warn_if_dangling_data data; data.fp = fp; data.refname = refname; data.msg_fmt = msg_fmt; for_each_rawref(warn_if_dangling_symref, &data); } static struct ref_list *get_loose_refs(const char *submodule) { if (submodule) { free_ref_list(submodule_refs.loose); submodule_refs.loose = get_ref_dir(submodule, "refs", NULL); return submodule_refs.loose; } if (!cached_refs.did_loose) { cached_refs.loose = get_ref_dir(NULL, "refs", NULL); cached_refs.did_loose = 1; } return cached_refs.loose; } /* We allow "recursive" symbolic refs. Only within reason, though */ #define MAXDEPTH 5 #define MAXREFLEN (1024) static int resolve_gitlink_packed_ref(char *name, int pathlen, const char *refname, unsigned char *result) { FILE *f; struct cached_refs refs; struct ref_list *ref; int retval; strcpy(name + pathlen, "packed-refs"); f = fopen(name, "r"); if (!f) return -1; read_packed_refs(f, &refs); fclose(f); ref = refs.packed; retval = -1; while (ref) { if (!strcmp(ref->name, refname)) { retval = 0; memcpy(result, ref->sha1, 20); break; } ref = ref->next; } free_ref_list(refs.packed); return retval; } static int resolve_gitlink_ref_recursive(char *name, int pathlen, const char *refname, unsigned char *result, int recursion) { int fd, len = strlen(refname); char buffer[128], *p; if (recursion > MAXDEPTH || len > MAXREFLEN) return -1; memcpy(name + pathlen, refname, len+1); fd = open(name, O_RDONLY); if (fd < 0) return resolve_gitlink_packed_ref(name, pathlen, refname, result); len = read(fd, buffer, sizeof(buffer)-1); close(fd); if (len < 0) return -1; while (len && isspace(buffer[len-1])) len--; buffer[len] = 0; /* Was it a detached head or an old-fashioned symlink? */ if (!get_sha1_hex(buffer, result)) return 0; /* Symref? */ if (strncmp(buffer, "ref:", 4)) return -1; p = buffer + 4; while (isspace(*p)) p++; return resolve_gitlink_ref_recursive(name, pathlen, p, result, recursion+1); } int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *result) { int len = strlen(path), retval; char *gitdir; const char *tmp; while (len && path[len-1] == '/') len--; if (!len) return -1; gitdir = xmalloc(len + MAXREFLEN + 8); memcpy(gitdir, path, len); memcpy(gitdir + len, "/.git", 6); len += 5; tmp = read_gitfile_gently(gitdir); if (tmp) { free(gitdir); len = strlen(tmp); gitdir = xmalloc(len + MAXREFLEN + 3); memcpy(gitdir, tmp, len); } gitdir[len] = '/'; gitdir[++len] = '\0'; retval = resolve_gitlink_ref_recursive(gitdir, len, refname, result, 0); free(gitdir); return retval; } /* * If the "reading" argument is set, this function finds out what _object_ * the ref points at by "reading" the ref. The ref, if it is not symbolic, * has to exist, and if it is symbolic, it has to point at an existing ref, * because the "read" goes through the symref to the ref it points at. * * The access that is not "reading" may often be "writing", but does not * have to; it can be merely checking _where it leads to_. If it is a * prelude to "writing" to the ref, a write to a symref that points at * yet-to-be-born ref will create the real ref pointed by the symref. * reading=0 allows the caller to check where such a symref leads to. */ const char *resolve_ref(const char *ref, unsigned char *sha1, int reading, int *flag) { int depth = MAXDEPTH; ssize_t len; char buffer[256]; static char ref_buffer[256]; if (flag) *flag = 0; for (;;) { char path[PATH_MAX]; struct stat st; char *buf; int fd; if (--depth < 0) return NULL; git_snpath(path, sizeof(path), "%s", ref); /* Special case: non-existing file. */ if (lstat(path, &st) < 0) { struct ref_list *list = get_packed_refs(NULL); 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; } /* The argument to filter_refs */ struct ref_filter { const char *pattern; each_ref_fn *fn; void *cb_data; }; int read_ref(const char *ref, unsigned char *sha1) { if (resolve_ref(ref, sha1, 1, NULL)) return 0; return -1; } #define DO_FOR_EACH_INCLUDE_BROKEN 01 static int do_one_ref(const char *base, each_ref_fn fn, int trim, int flags, void *cb_data, struct ref_list *entry) { if (prefixcmp(entry->name, base)) return 0; if (!(flags & DO_FOR_EACH_INCLUDE_BROKEN)) { if (entry->flag & REF_BROKEN) return 0; /* ignore dangling symref */ if (!has_sha1_file(entry->sha1)) { error("%s does not point to a valid object!", entry->name); return 0; } } current_ref = entry; return fn(entry->name + trim, entry->sha1, entry->flag, cb_data); } static int filter_refs(const char *ref, const unsigned char *sha, int flags, void *data) { struct ref_filter *filter = (struct ref_filter *)data; if (fnmatch(filter->pattern, ref, 0)) return 0; return filter->fn(ref, sha, flags, filter->cb_data); } int peel_ref(const char *ref, unsigned char *sha1) { int flag; unsigned char base[20]; struct object *o; if (current_ref && (current_ref->name == ref || !strcmp(current_ref->name, ref))) { if (current_ref->flag & REF_KNOWS_PEELED) { hashcpy(sha1, current_ref->peeled); return 0; } hashcpy(base, current_ref->sha1); goto fallback; } if (!resolve_ref(ref, base, 1, &flag)) return -1; if ((flag & REF_ISPACKED)) { struct ref_list *list = get_packed_refs(NULL); 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: o = parse_object(base); if (o && 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 *submodule, const char *base, each_ref_fn fn, int trim, int flags, void *cb_data) { int retval = 0; struct ref_list *packed = get_packed_refs(submodule); struct ref_list *loose = get_loose_refs(submodule); struct ref_list *extra; for (extra = extra_refs; extra; extra = extra->next) retval = do_one_ref(base, fn, trim, flags, cb_data, extra); 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, flags, cb_data, entry); if (retval) goto end_each; } for (packed = packed ? packed : loose; packed; packed = packed->next) { retval = do_one_ref(base, fn, trim, flags, cb_data, packed); if (retval) goto end_each; } end_each: current_ref = NULL; return retval; } static int do_head_ref(const char *submodule, each_ref_fn fn, void *cb_data) { unsigned char sha1[20]; int flag; if (submodule) { if (resolve_gitlink_ref(submodule, "HEAD", sha1) == 0) return fn("HEAD", sha1, 0, cb_data); return 0; } if (resolve_ref("HEAD", sha1, 1, &flag)) return fn("HEAD", sha1, flag, cb_data); return 0; } int head_ref(each_ref_fn fn, void *cb_data) { return do_head_ref(NULL, fn, cb_data); } int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data) { return do_head_ref(submodule, fn, cb_data); } int for_each_ref(each_ref_fn fn, void *cb_data) { return do_for_each_ref(NULL, "", fn, 0, 0, cb_data); } int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data) { return do_for_each_ref(submodule, "", fn, 0, 0, cb_data); } int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data) { return do_for_each_ref(NULL, prefix, fn, strlen(prefix), 0, cb_data); } int for_each_ref_in_submodule(const char *submodule, const char *prefix, each_ref_fn fn, void *cb_data) { return do_for_each_ref(submodule, prefix, fn, strlen(prefix), 0, cb_data); } int for_each_tag_ref(each_ref_fn fn, void *cb_data) { return for_each_ref_in("refs/tags/", fn, cb_data); } int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data) { return for_each_ref_in_submodule(submodule, "refs/tags/", fn, cb_data); } int for_each_branch_ref(each_ref_fn fn, void *cb_data) { return for_each_ref_in("refs/heads/", fn, cb_data); } int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data) { return for_each_ref_in_submodule(submodule, "refs/heads/", fn, cb_data); } int for_each_remote_ref(each_ref_fn fn, void *cb_data) { return for_each_ref_in("refs/remotes/", fn, cb_data); } int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data) { return for_each_ref_in_submodule(submodule, "refs/remotes/", fn, cb_data); } int for_each_replace_ref(each_ref_fn fn, void *cb_data) { return do_for_each_ref(NULL, "refs/replace/", fn, 13, 0, cb_data); } int for_each_glob_ref_in(each_ref_fn fn, const char *pattern, const char *prefix, void *cb_data) { struct strbuf real_pattern = STRBUF_INIT; struct ref_filter filter; int ret; if (!prefix && prefixcmp(pattern, "refs/")) strbuf_addstr(&real_pattern, "refs/"); else if (prefix) strbuf_addstr(&real_pattern, prefix); strbuf_addstr(&real_pattern, pattern); if (!has_glob_specials(pattern)) { /* Append implied '/' '*' if not present. */ if (real_pattern.buf[real_pattern.len - 1] != '/') strbuf_addch(&real_pattern, '/'); /* No need to check for '*', there is none. */ strbuf_addch(&real_pattern, '*'); } filter.pattern = real_pattern.buf; filter.fn = fn; filter.cb_data = cb_data; ret = for_each_ref(filter_refs, &filter); strbuf_release(&real_pattern); return ret; } int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data) { return for_each_glob_ref_in(fn, pattern, NULL, cb_data); } int for_each_rawref(each_ref_fn fn, void *cb_data) { return do_for_each_ref(NULL, "", fn, 0, DO_FOR_EACH_INCLUDE_BROKEN, cb_data); } /* * 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 "/". * - it ends with ".lock" * - it contains a "\" (backslash) */ static inline int bad_ref_char(int ch) { if (((unsigned) ch) <= ' ' || ch == '~' || ch == '^' || ch == ':' || ch == '\\') return 1; /* 2.13 Pattern Matching Notation */ if (ch == '?' || ch == '[') /* Unsupported */ return 1; if (ch == '*') /* Supported at the end */ return 2; return 0; } int check_ref_format(const char *ref) { int ch, level, bad_type, last; int ret = CHECK_REF_FORMAT_OK; const char *cp = ref; level = 0; while (1) { while ((ch = *cp++) == '/') ; /* tolerate duplicated slashes */ if (!ch) /* should not end with slashes */ return CHECK_REF_FORMAT_ERROR; /* we are at the beginning of the path component */ if (ch == '.') return CHECK_REF_FORMAT_ERROR; bad_type = bad_ref_char(ch); if (bad_type) { if (bad_type == 2 && (!*cp || *cp == '/') && ret == CHECK_REF_FORMAT_OK) ret = CHECK_REF_FORMAT_WILDCARD; else return CHECK_REF_FORMAT_ERROR; } last = ch; /* scan the rest of the path component */ while ((ch = *cp++) != 0) { bad_type = bad_ref_char(ch); if (bad_type) return CHECK_REF_FORMAT_ERROR; if (ch == '/') break; if (last == '.' && ch == '.') return CHECK_REF_FORMAT_ERROR; if (last == '@' && ch == '{') return CHECK_REF_FORMAT_ERROR; last = ch; } level++; if (!ch) { if (ref <= cp - 2 && cp[-2] == '.') return CHECK_REF_FORMAT_ERROR; if (level < 2) return CHECK_REF_FORMAT_ONELEVEL; if (has_extension(ref, ".lock")) return CHECK_REF_FORMAT_ERROR; return ret; } } } const char *prettify_refname(const char *name) { return name + ( !prefixcmp(name, "refs/heads/") ? 11 : !prefixcmp(name, "refs/tags/") ? 10 : !prefixcmp(name, "refs/remotes/") ? 13 : 0); } const char *ref_rev_parse_rules[] = { "%.*s", "refs/%.*s", "refs/tags/%.*s", "refs/heads/%.*s", "refs/remotes/%.*s", "refs/remotes/%.*s/HEAD", NULL }; const char *ref_fetch_rules[] = { "%.*s", "refs/%.*s", "refs/heads/%.*s", NULL }; int refname_match(const char *abbrev_name, const char *full_name, const char **rules) { const char **p; const int abbrev_name_len = strlen(abbrev_name); for (p = rules; *p; p++) { if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) { return 1; } } 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_directories(const 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. */ struct strbuf path; int result; strbuf_init(&path, 20); strbuf_addstr(&path, file); result = remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY); strbuf_release(&path); return result; } 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 flags, int *type_p) { char *ref_file; const char *orig_ref = ref; struct ref_lock *lock; int last_errno = 0; int type, lflags; int mustexist = (old_sha1 && !is_null_sha1(old_sha1)); int missing = 0; lock = xcalloc(1, sizeof(struct ref_lock)); lock->lock_fd = -1; ref = resolve_ref(ref, lock->old_sha1, mustexist, &type); 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, &type); } if (type_p) *type_p = type; if (!ref) { last_errno = errno; error("unable to resolve reference %s: %s", orig_ref, strerror(errno)); goto error_return; } missing = is_null_sha1(lock->old_sha1); /* 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 (missing && !is_refname_available(ref, NULL, get_packed_refs(NULL), 0)) { last_errno = ENOTDIR; goto error_return; } lock->lk = xcalloc(1, sizeof(struct lock_file)); lflags = LOCK_DIE_ON_ERROR; if (flags & REF_NODEREF) { ref = orig_ref; lflags |= LOCK_NODEREF; } lock->ref_name = xstrdup(ref); lock->orig_ref_name = xstrdup(orig_ref); ref_file = git_path("%s", ref); if (missing) lock->force_write = 1; if ((flags & REF_NODEREF) && (type & REF_ISSYMREF)) lock->force_write = 1; 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, lflags); 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, 0, NULL); } struct ref_lock *lock_any_ref_for_update(const char *ref, const unsigned char *old_sha1, int flags) { switch (check_ref_format(ref)) { default: return NULL; case 0: case CHECK_REF_FORMAT_ONELEVEL: return lock_ref_sha1_basic(ref, old_sha1, flags, 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(NULL); 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) { unable_to_lock_error(git_path("packed-refs"), errno); 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, const unsigned char *sha1, int delopt) { struct ref_lock *lock; int err, i = 0, ret = 0, flag = 0; lock = lock_ref_sha1_basic(refname, sha1, 0, &flag); if (!lock) return 1; if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) { /* loose */ const char *path; if (!(delopt & REF_NODEREF)) { i = strlen(lock->lk->filename) - 5; /* .lock */ lock->lk->filename[i] = 0; path = lock->lk->filename; } else { path = git_path("%s", refname); } err = unlink_or_warn(path); if (err && errno != ENOENT) ret = 1; if (!(delopt & REF_NODEREF)) 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); unlink_or_warn(git_path("logs/%s", lock->ref_name)); invalidate_cached_refs(); unlock_ref(lock); return ret; } /* * People using contrib's git-new-workdir have .git/logs/refs -> * /some/other/path/.git/logs/refs, and that may live on another device. * * IOW, to avoid cross device rename errors, the temporary renamed log must * live into logs/refs. */ #define TMP_RENAMED_LOG "logs/refs/.tmp-renamed-log" 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); const char *symref = NULL; if (log && S_ISLNK(loginfo.st_mode)) return error("reflog for %s is a symlink", oldref); symref = resolve_ref(oldref, orig_sha1, 1, &flag); if (flag & REF_ISSYMREF) return error("refname %s is a symbolic ref, renaming it is not supported", oldref); if (!symref) return error("refname %s not found", oldref); if (!is_refname_available(newref, oldref, get_packed_refs(NULL), 0)) return 1; if (!is_refname_available(newref, oldref, get_loose_refs(NULL), 0)) return 1; lock = lock_ref_sha1_basic(renamed_ref, NULL, 0, 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, REF_NODEREF)) { error("unable to delete old %s", oldref); goto rollback; } if (resolve_ref(newref, sha1, 1, &flag) && delete_ref(newref, sha1, REF_NODEREF)) { 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, 0, 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; } return 0; rollback: lock = lock_ref_sha1_basic(oldref, NULL, 0, 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; } int close_ref(struct ref_lock *lock) { if (close_lock_file(lock->lk)) return -1; lock->lock_fd = -1; return 0; } int commit_ref(struct ref_lock *lock) { if (commit_lock_file(lock->lk)) return -1; lock->lock_fd = -1; return 0; } void unlock_ref(struct ref_lock *lock) { /* 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); } /* * copy the reflog message msg to buf, which has been allocated sufficiently * large, while cleaning up the whitespaces. Especially, convert LF to space, * because reflog file is one line per entry. */ static int copy_msg(char *buf, const char *msg) { char *cp = buf; char c; int wasspace = 1; *cp++ = '\t'; while ((c = *msg++)) { if (wasspace && isspace(c)) continue; wasspace = isspace(c); if (wasspace) c = ' '; *cp++ = c; } while (buf < cp && isspace(cp[-1])) cp--; *cp++ = '\n'; return cp - buf; } int log_ref_setup(const char *ref_name, char *logfile, int bufsize) { int logfd, oflags = O_APPEND | O_WRONLY; git_snpath(logfile, bufsize, "logs/%s", ref_name); if (log_all_ref_updates && (!prefixcmp(ref_name, "refs/heads/") || !prefixcmp(ref_name, "refs/remotes/") || !prefixcmp(ref_name, "refs/notes/") || !strcmp(ref_name, "HEAD"))) { if (safe_create_leading_directories(logfile) < 0) return error("unable to create directory for %s", logfile); oflags |= O_CREAT; } logfd = open(logfile, oflags, 0666); if (logfd < 0) { if (!(oflags & O_CREAT) && errno == ENOENT) return 0; if ((oflags & O_CREAT) && errno == EISDIR) { if (remove_empty_directories(logfile)) { return error("There are still logs under '%s'", logfile); } logfd = open(logfile, oflags, 0666); } if (logfd < 0) return error("Unable to append to %s: %s", logfile, strerror(errno)); } adjust_shared_perm(logfile); close(logfd); return 0; } static int log_ref_write(const char *ref_name, const unsigned char *old_sha1, const unsigned char *new_sha1, const char *msg) { int logfd, result, written, oflags = O_APPEND | O_WRONLY; unsigned maxlen, len; int msglen; char log_file[PATH_MAX]; char *logrec; const char *committer; if (log_all_ref_updates < 0) log_all_ref_updates = !is_bare_repository(); result = log_ref_setup(ref_name, log_file, sizeof(log_file)); if (result) return result; logfd = open(log_file, oflags); if (logfd < 0) return 0; msglen = msg ? strlen(msg) : 0; committer = git_committer_info(0); 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 += copy_msg(logrec + len - 1, msg) - 1; written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1; free(logrec); if (close(logfd) != 0 || written != len) return error("Unable to append to %s", log_file); return 0; } static int is_branch(const char *refname) { return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/"); } int write_ref_sha1(struct ref_lock *lock, const unsigned char *sha1, const char *logmsg) { static char term = '\n'; struct object *o; if (!lock) return -1; if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) { unlock_ref(lock); return 0; } o = parse_object(sha1); if (!o) { error("Trying to write ref %s with nonexistant object %s", lock->ref_name, sha1_to_hex(sha1)); unlock_ref(lock); return -1; } if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) { error("Trying to write non-commit object %s to branch %s", sha1_to_hex(sha1), lock->ref_name); unlock_ref(lock); return -1; } if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 || write_in_full(lock->lock_fd, &term, 1) != 1 || close_ref(lock) < 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 (strcmp(lock->orig_ref_name, "HEAD") != 0) { /* * Special hack: If a branch is updated directly and HEAD * points to it (may happen on the remote side of a push * for example) then logically the HEAD reflog should be * updated too. * A generic solution implies reverse symref information, * but finding all symrefs pointing to the given branch * would be rather costly for this rare event (the direct * update of a branch) to be worth it. So let's cheat and * check with HEAD only which should cover 99% of all usage * scenarios (even 100% of the default ones). */ unsigned char head_sha1[20]; int head_flag; const char *head_ref; head_ref = resolve_ref("HEAD", head_sha1, 1, &head_flag); if (head_ref && (head_flag & REF_ISSYMREF) && !strcmp(head_ref, lock->ref_name)) log_ref_write("HEAD", lock->old_sha1, sha1, logmsg); } if (commit_ref(lock)) { error("Couldn't set %s", lock->ref_name); unlock_ref(lock); return -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 = git_pathdup("%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); if (close(fd) != 0 || 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_or_warn(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; line += 82; ep = memchr(line, '\n', endp - line); if (!ep) ep = endp; return xmemdupz(line, ep - line); } 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_errno("Unable to read log '%s'", logfile); 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)) { warning("Log %s has gap after %s.", logfile, show_date(date, tz, DATE_RFC2822)); } } 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)) { warning("Log %s unexpectedly ended on %s.", logfile, show_date(date, tz, DATE_RFC2822)); } } 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 (is_null_sha1(sha1)) { if (get_sha1_hex(logdata + 41, 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_recent_reflog_ent(const char *ref, each_reflog_ent_fn fn, long ofs, void *cb_data) { const char *logfile; FILE *logfp; struct strbuf sb = STRBUF_INIT; int ret = 0; logfile = git_path("logs/%s", ref); logfp = fopen(logfile, "r"); if (!logfp) return -1; if (ofs) { struct stat statbuf; if (fstat(fileno(logfp), &statbuf) || statbuf.st_size < ofs || fseek(logfp, -ofs, SEEK_END) || strbuf_getwholeline(&sb, logfp, '\n')) { fclose(logfp); strbuf_release(&sb); return -1; } } while (!strbuf_getwholeline(&sb, logfp, '\n')) { unsigned char osha1[20], nsha1[20]; char *email_end, *message; unsigned long timestamp; int tz; /* old SP new SP name SP time TAB msg LF */ if (sb.len < 83 || sb.buf[sb.len - 1] != '\n' || get_sha1_hex(sb.buf, osha1) || sb.buf[40] != ' ' || get_sha1_hex(sb.buf + 41, nsha1) || sb.buf[81] != ' ' || !(email_end = strchr(sb.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, sb.buf + 82, timestamp, tz, message, cb_data); if (ret) break; } fclose(logfp); strbuf_release(&sb); return ret; } int for_each_reflog_ent(const char *ref, each_reflog_ent_fn fn, void *cb_data) { return for_each_recent_reflog_ent(ref, fn, 0, cb_data); } 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); } int update_ref(const char *action, const char *refname, const unsigned char *sha1, const unsigned char *oldval, int flags, enum action_on_err onerr) { static struct ref_lock *lock; lock = lock_any_ref_for_update(refname, oldval, flags); if (!lock) { const char *str = "Cannot lock the ref '%s'."; switch (onerr) { case MSG_ON_ERR: error(str, refname); break; case DIE_ON_ERR: die(str, refname); break; case QUIET_ON_ERR: break; } return 1; } if (write_ref_sha1(lock, sha1, action) < 0) { const char *str = "Cannot update the ref '%s'."; switch (onerr) { case MSG_ON_ERR: error(str, refname); break; case DIE_ON_ERR: die(str, refname); break; case QUIET_ON_ERR: break; } return 1; } return 0; } struct ref *find_ref_by_name(const struct ref *list, const char *name) { for ( ; list; list = list->next) if (!strcmp(list->name, name)) return (struct ref *)list; return NULL; } /* * generate a format suitable for scanf from a ref_rev_parse_rules * rule, that is replace the "%.*s" spec with a "%s" spec */ static void gen_scanf_fmt(char *scanf_fmt, const char *rule) { char *spec; spec = strstr(rule, "%.*s"); if (!spec || strstr(spec + 4, "%.*s")) die("invalid rule in ref_rev_parse_rules: %s", rule); /* copy all until spec */ strncpy(scanf_fmt, rule, spec - rule); scanf_fmt[spec - rule] = '\0'; /* copy new spec */ strcat(scanf_fmt, "%s"); /* copy remaining rule */ strcat(scanf_fmt, spec + 4); return; } char *shorten_unambiguous_ref(const char *ref, int strict) { int i; static char **scanf_fmts; static int nr_rules; char *short_name; /* pre generate scanf formats from ref_rev_parse_rules[] */ if (!nr_rules) { size_t total_len = 0; /* the rule list is NULL terminated, count them first */ for (; ref_rev_parse_rules[nr_rules]; nr_rules++) /* no +1 because strlen("%s") < strlen("%.*s") */ total_len += strlen(ref_rev_parse_rules[nr_rules]); scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len); total_len = 0; for (i = 0; i < nr_rules; i++) { scanf_fmts[i] = (char *)&scanf_fmts[nr_rules] + total_len; gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]); total_len += strlen(ref_rev_parse_rules[i]); } } /* bail out if there are no rules */ if (!nr_rules) return xstrdup(ref); /* buffer for scanf result, at most ref must fit */ short_name = xstrdup(ref); /* skip first rule, it will always match */ for (i = nr_rules - 1; i > 0 ; --i) { int j; int rules_to_fail = i; int short_name_len; if (1 != sscanf(ref, scanf_fmts[i], short_name)) continue; short_name_len = strlen(short_name); /* * in strict mode, all (except the matched one) rules * must fail to resolve to a valid non-ambiguous ref */ if (strict) rules_to_fail = nr_rules; /* * check if the short name resolves to a valid ref, * but use only rules prior to the matched one */ for (j = 0; j < rules_to_fail; j++) { const char *rule = ref_rev_parse_rules[j]; unsigned char short_objectname[20]; char refname[PATH_MAX]; /* skip matched rule */ if (i == j) continue; /* * the short name is ambiguous, if it resolves * (with this previous rule) to a valid ref * read_ref() returns 0 on success */ mksnpath(refname, sizeof(refname), rule, short_name_len, short_name); if (!read_ref(refname, short_objectname)) break; } /* * short name is non-ambiguous if all previous rules * haven't resolved to a valid ref */ if (j == rules_to_fail) return short_name; } free(short_name); return xstrdup(ref); }