Merge 'kn/for-each-tag-branch' into kn/for-each-tag
[gitweb.git] / refs.c
diff --git a/refs.c b/refs.c
index 388ac3ed357212fd40139ebc1533c80b78a3fb60..2db2975e08b7cccd644eab6b4b0ad752e4ec02b3 100644 (file)
--- a/refs.c
+++ b/refs.c
@@ -19,12 +19,14 @@ struct ref_lock {
  * 1: End-of-component
  * 2: ., look for a preceding . to reject .. in refs
  * 3: {, look for a preceding @ to reject @{ in refs
- * 4: A bad character: ASCII control characters, "~", "^", ":" or SP
+ * 4: A bad character: ASCII control characters, and
+ *    ":", "?", "[", "\", "^", "~", SP, or TAB
+ * 5: *, reject unless REFNAME_REFSPEC_PATTERN is set
  */
 static unsigned char refname_disposition[256] = {
        1, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
        4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
-       4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 0, 0, 0, 2, 1,
+       4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 5, 0, 0, 0, 2, 1,
        0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 0, 0, 0, 0, 4,
        0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
        0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 4, 0, 4, 0,
@@ -62,6 +64,11 @@ static unsigned char refname_disposition[256] = {
  */
 #define REF_NEEDS_COMMIT 0x20
 
+/*
+ * 0x40 is REF_FORCE_CREATE_REFLOG, so skip it if you're adding a
+ * value to ref_update::flags
+ */
+
 /*
  * Try to read one refname component from the front of refname.
  * Return the length of the component found, or -1 if the component is
@@ -70,12 +77,14 @@ static unsigned char refname_disposition[256] = {
  *
  * - 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)
+ * - it has ASCII control characters, or
+ * - it has ":", "?", "[", "\", "^", "~", SP, or TAB anywhere, or
+ * - it has "*" anywhere unless REFNAME_REFSPEC_PATTERN is set, or
+ * - it ends with a "/", or
+ * - it ends with ".lock", or
+ * - it contains a "@{" portion
  */
-static int check_refname_component(const char *refname, int flags)
+static int check_refname_component(const char *refname, int *flags)
 {
        const char *cp;
        char last = '\0';
@@ -96,6 +105,16 @@ static int check_refname_component(const char *refname, int flags)
                        break;
                case 4:
                        return -1;
+               case 5:
+                       if (!(*flags & REFNAME_REFSPEC_PATTERN))
+                               return -1; /* refspec can't be a pattern */
+
+                       /*
+                        * Unset the pattern flag so that we only accept
+                        * a single asterisk for one side of refspec.
+                        */
+                       *flags &= ~ REFNAME_REFSPEC_PATTERN;
+                       break;
                }
                last = ch;
        }
@@ -120,18 +139,10 @@ int check_refname_format(const char *refname, int flags)
 
        while (1) {
                /* We are at the start of a path component. */
-               component_len = check_refname_component(refname, flags);
-               if (component_len <= 0) {
-                       if ((flags & REFNAME_REFSPEC_PATTERN) &&
-                                       refname[0] == '*' &&
-                                       (refname[1] == '\0' || refname[1] == '/')) {
-                               /* Accept one wildcard as a full refname component. */
-                               flags &= ~REFNAME_REFSPEC_PATTERN;
-                               component_len = 1;
-                       } else {
-                               return -1;
-                       }
-               }
+               component_len = check_refname_component(refname, &flags);
+               if (component_len <= 0)
+                       return -1;
+
                component_count++;
                if (refname[component_len] == '\0')
                        break;
@@ -1379,19 +1390,34 @@ static void read_loose_refs(const char *dirname, struct ref_dir *dir)
                                         create_dir_entry(refs, refname.buf,
                                                          refname.len, 1));
                } else {
+                       int read_ok;
+
                        if (*refs->name) {
                                hashclr(sha1);
                                flag = 0;
-                               if (resolve_gitlink_ref(refs->name, refname.buf, sha1) < 0) {
-                                       hashclr(sha1);
-                                       flag |= REF_ISBROKEN;
-                               }
-                       } else if (read_ref_full(refname.buf,
-                                                RESOLVE_REF_READING,
-                                                sha1, &flag)) {
+                               read_ok = !resolve_gitlink_ref(refs->name,
+                                                              refname.buf, sha1);
+                       } else {
+                               read_ok = !read_ref_full(refname.buf,
+                                                        RESOLVE_REF_READING,
+                                                        sha1, &flag);
+                       }
+
+                       if (!read_ok) {
                                hashclr(sha1);
                                flag |= REF_ISBROKEN;
+                       } else if (is_null_sha1(sha1)) {
+                               /*
+                                * It is so astronomically unlikely
+                                * that NULL_SHA1 is the SHA-1 of an
+                                * actual object that we consider its
+                                * appearance in a loose reference
+                                * file to be repo corruption
+                                * (probably due to a software bug).
+                                */
+                               flag |= REF_ISBROKEN;
                        }
+
                        if (check_refname_format(refname.buf,
                                                 REFNAME_ALLOW_ONELEVEL)) {
                                if (!refname_is_safe(refname.buf))
@@ -1732,9 +1758,11 @@ const char *resolve_ref_unsafe(const char *refname, int resolve_flags,
        return ret;
 }
 
-char *resolve_refdup(const char *ref, int resolve_flags, unsigned char *sha1, int *flags)
+char *resolve_refdup(const char *refname, int resolve_flags,
+                    unsigned char *sha1, int *flags)
 {
-       return xstrdup_or_null(resolve_ref_unsafe(ref, resolve_flags, sha1, flags));
+       return xstrdup_or_null(resolve_ref_unsafe(refname, resolve_flags,
+                                                 sha1, flags));
 }
 
 /* The argument to filter_refs */
@@ -2113,7 +2141,8 @@ int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *c
 
 int for_each_replace_ref(each_ref_fn fn, void *cb_data)
 {
-       return do_for_each_ref(&ref_cache, "refs/replace/", fn, 13, 0, cb_data);
+       return do_for_each_ref(&ref_cache, git_replace_ref_base, fn,
+                              strlen(git_replace_ref_base), 0, cb_data);
 }
 
 int head_ref_namespaced(each_ref_fn fn, void *cb_data)
@@ -2831,14 +2860,6 @@ int delete_ref(const char *refname, const unsigned char *old_sha1,
        struct ref_transaction *transaction;
        struct strbuf err = STRBUF_INIT;
 
-       /*
-        * Treat NULL_SHA1 and NULL alike, to mean "we don't care what
-        * the old value of the reference was (or even if it didn't
-        * exist)":
-        */
-       if (old_sha1 && is_null_sha1(old_sha1))
-               old_sha1 = NULL;
-
        transaction = ref_transaction_begin(&err);
        if (!transaction ||
            ref_transaction_delete(transaction, refname, old_sha1,
@@ -2965,9 +2986,11 @@ static int rename_ref_available(const char *oldname, const char *newname)
        return ret;
 }
 
-static int write_ref_to_lockfile(struct ref_lock *lock, const unsigned char *sha1);
+static int write_ref_to_lockfile(struct ref_lock *lock,
+                                const unsigned char *sha1, struct strbuf *err);
 static int commit_ref_update(struct ref_lock *lock,
-                            const unsigned char *sha1, const char *logmsg);
+                            const unsigned char *sha1, const char *logmsg,
+                            int flags, struct strbuf *err);
 
 int rename_ref(const char *oldrefname, const char *newrefname, const char *logmsg)
 {
@@ -3028,9 +3051,10 @@ int rename_ref(const char *oldrefname, const char *newrefname, const char *logms
        }
        hashcpy(lock->old_oid.hash, orig_sha1);
 
-       if (write_ref_to_lockfile(lock, orig_sha1) ||
-           commit_ref_update(lock, orig_sha1, logmsg)) {
-               error("unable to write current sha1 into %s", newrefname);
+       if (write_ref_to_lockfile(lock, orig_sha1, &err) ||
+           commit_ref_update(lock, orig_sha1, logmsg, 0, &err)) {
+               error("unable to write current sha1 into %s: %s", newrefname, err.buf);
+               strbuf_release(&err);
                goto rollback;
        }
 
@@ -3046,9 +3070,11 @@ int rename_ref(const char *oldrefname, const char *newrefname, const char *logms
 
        flag = log_all_ref_updates;
        log_all_ref_updates = 0;
-       if (write_ref_to_lockfile(lock, orig_sha1) ||
-           commit_ref_update(lock, orig_sha1, NULL))
-               error("unable to write current sha1 into %s", oldrefname);
+       if (write_ref_to_lockfile(lock, orig_sha1, &err) ||
+           commit_ref_update(lock, orig_sha1, NULL, 0, &err)) {
+               error("unable to write current sha1 into %s: %s", oldrefname, err.buf);
+               strbuf_release(&err);
+       }
        log_all_ref_updates = flag;
 
  rollbacklog:
@@ -3103,8 +3129,23 @@ static int copy_msg(char *buf, const char *msg)
        return cp - buf;
 }
 
-/* This function must set a meaningful errno on failure */
-int log_ref_setup(const char *refname, struct strbuf *sb_logfile)
+static int should_autocreate_reflog(const char *refname)
+{
+       if (!log_all_ref_updates)
+               return 0;
+       return starts_with(refname, "refs/heads/") ||
+               starts_with(refname, "refs/remotes/") ||
+               starts_with(refname, "refs/notes/") ||
+               !strcmp(refname, "HEAD");
+}
+
+/*
+ * Create a reflog for a ref.  If force_create = 0, the reflog will
+ * only be created for certain refs (those for which
+ * should_autocreate_reflog returns non-zero.  Otherwise, create it
+ * regardless of the ref name.  Fill in *err and return -1 on failure.
+ */
+static int log_ref_setup(const char *refname, struct strbuf *sb_logfile, struct strbuf *err, int force_create)
 {
        int logfd, oflags = O_APPEND | O_WRONLY;
        char *logfile;
@@ -3113,15 +3154,10 @@ int log_ref_setup(const char *refname, struct strbuf *sb_logfile)
        logfile = sb_logfile->buf;
        /* make sure the rest of the function can't change "logfile" */
        sb_logfile = NULL;
-       if (log_all_ref_updates &&
-           (starts_with(refname, "refs/heads/") ||
-            starts_with(refname, "refs/remotes/") ||
-            starts_with(refname, "refs/notes/") ||
-            !strcmp(refname, "HEAD"))) {
+       if (force_create || should_autocreate_reflog(refname)) {
                if (safe_create_leading_directories(logfile) < 0) {
-                       int save_errno = errno;
-                       error("unable to create directory for %s", logfile);
-                       errno = save_errno;
+                       strbuf_addf(err, "unable to create directory for %s: "
+                                   "%s", logfile, strerror(errno));
                        return -1;
                }
                oflags |= O_CREAT;
@@ -3134,20 +3170,16 @@ int log_ref_setup(const char *refname, struct strbuf *sb_logfile)
 
                if (errno == EISDIR) {
                        if (remove_empty_directories(logfile)) {
-                               int save_errno = errno;
-                               error("There are still logs under '%s'",
-                                     logfile);
-                               errno = save_errno;
+                               strbuf_addf(err, "There are still logs under "
+                                           "'%s'", logfile);
                                return -1;
                        }
                        logfd = open(logfile, oflags, 0666);
                }
 
                if (logfd < 0) {
-                       int save_errno = errno;
-                       error("Unable to append to %s: %s", logfile,
-                             strerror(errno));
-                       errno = save_errno;
+                       strbuf_addf(err, "unable to append to %s: %s",
+                                   logfile, strerror(errno));
                        return -1;
                }
        }
@@ -3157,6 +3189,17 @@ int log_ref_setup(const char *refname, struct strbuf *sb_logfile)
        return 0;
 }
 
+
+int safe_create_reflog(const char *refname, int force_create, struct strbuf *err)
+{
+       int ret;
+       struct strbuf sb = STRBUF_INIT;
+
+       ret = log_ref_setup(refname, &sb, err, force_create);
+       strbuf_release(&sb);
+       return ret;
+}
+
 static int log_ref_write_fd(int fd, const unsigned char *old_sha1,
                            const unsigned char *new_sha1,
                            const char *committer, const char *msg)
@@ -3185,7 +3228,8 @@ static int log_ref_write_fd(int fd, const unsigned char *old_sha1,
 
 static int log_ref_write_1(const char *refname, const unsigned char *old_sha1,
                           const unsigned char *new_sha1, const char *msg,
-                          struct strbuf *sb_log_file)
+                          struct strbuf *sb_log_file, int flags,
+                          struct strbuf *err)
 {
        int logfd, result, oflags = O_APPEND | O_WRONLY;
        char *log_file;
@@ -3193,7 +3237,8 @@ static int log_ref_write_1(const char *refname, const unsigned char *old_sha1,
        if (log_all_ref_updates < 0)
                log_all_ref_updates = !is_bare_repository();
 
-       result = log_ref_setup(refname, sb_log_file);
+       result = log_ref_setup(refname, sb_log_file, err, flags & REF_FORCE_CREATE_REFLOG);
+
        if (result)
                return result;
        log_file = sb_log_file->buf;
@@ -3206,26 +3251,26 @@ static int log_ref_write_1(const char *refname, const unsigned char *old_sha1,
        result = log_ref_write_fd(logfd, old_sha1, new_sha1,
                                  git_committer_info(0), msg);
        if (result) {
-               int save_errno = errno;
+               strbuf_addf(err, "unable to append to %s: %s", log_file,
+                           strerror(errno));
                close(logfd);
-               error("Unable to append to %s", log_file);
-               errno = save_errno;
                return -1;
        }
        if (close(logfd)) {
-               int save_errno = errno;
-               error("Unable to append to %s", log_file);
-               errno = save_errno;
+               strbuf_addf(err, "unable to append to %s: %s", log_file,
+                           strerror(errno));
                return -1;
        }
        return 0;
 }
 
 static int log_ref_write(const char *refname, const unsigned char *old_sha1,
-                        const unsigned char *new_sha1, const char *msg)
+                        const unsigned char *new_sha1, const char *msg,
+                        int flags, struct strbuf *err)
 {
        struct strbuf sb = STRBUF_INIT;
-       int ret = log_ref_write_1(refname, old_sha1, new_sha1, msg, &sb);
+       int ret = log_ref_write_1(refname, old_sha1, new_sha1, msg, &sb, flags,
+                                 err);
        strbuf_release(&sb);
        return ret;
 }
@@ -3237,36 +3282,36 @@ int is_branch(const char *refname)
 
 /*
  * Write sha1 into the open lockfile, then close the lockfile. On
- * errors, rollback the lockfile and set errno to reflect the problem.
+ * errors, rollback the lockfile, fill in *err and
+ * return -1.
  */
 static int write_ref_to_lockfile(struct ref_lock *lock,
-                                const unsigned char *sha1)
+                                const unsigned char *sha1, struct strbuf *err)
 {
        static char term = '\n';
        struct object *o;
 
        o = parse_object(sha1);
        if (!o) {
-               error("Trying to write ref %s with nonexistent object %s",
-                       lock->ref_name, sha1_to_hex(sha1));
+               strbuf_addf(err,
+                           "Trying to write ref %s with nonexistent object %s",
+                           lock->ref_name, sha1_to_hex(sha1));
                unlock_ref(lock);
-               errno = EINVAL;
                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);
+               strbuf_addf(err,
+                           "Trying to write non-commit object %s to branch %s",
+                           sha1_to_hex(sha1), lock->ref_name);
                unlock_ref(lock);
-               errno = EINVAL;
                return -1;
        }
        if (write_in_full(lock->lk->fd, sha1_to_hex(sha1), 40) != 40 ||
            write_in_full(lock->lk->fd, &term, 1) != 1 ||
            close_ref(lock) < 0) {
-               int save_errno = errno;
-               error("Couldn't write %s", lock->lk->filename.buf);
+               strbuf_addf(err,
+                           "Couldn't write %s", lock->lk->filename.buf);
                unlock_ref(lock);
-               errno = save_errno;
                return -1;
        }
        return 0;
@@ -3278,12 +3323,17 @@ static int write_ref_to_lockfile(struct ref_lock *lock,
  * necessary, using the specified lockmsg (which can be NULL).
  */
 static int commit_ref_update(struct ref_lock *lock,
-                            const unsigned char *sha1, const char *logmsg)
+                            const unsigned char *sha1, const char *logmsg,
+                            int flags, struct strbuf *err)
 {
        clear_loose_ref_cache(&ref_cache);
-       if (log_ref_write(lock->ref_name, lock->old_oid.hash, sha1, logmsg) < 0 ||
+       if (log_ref_write(lock->ref_name, lock->old_oid.hash, sha1, logmsg, flags, err) < 0 ||
            (strcmp(lock->ref_name, lock->orig_ref_name) &&
-            log_ref_write(lock->orig_ref_name, lock->old_oid.hash, sha1, logmsg) < 0)) {
+            log_ref_write(lock->orig_ref_name, lock->old_oid.hash, sha1, logmsg, flags, err) < 0)) {
+               char *old_msg = strbuf_detach(err, NULL);
+               strbuf_addf(err, "Cannot update the ref '%s': %s",
+                           lock->ref_name, old_msg);
+               free(old_msg);
                unlock_ref(lock);
                return -1;
        }
@@ -3306,14 +3356,21 @@ static int commit_ref_update(struct ref_lock *lock,
                head_ref = resolve_ref_unsafe("HEAD", RESOLVE_REF_READING,
                                              head_sha1, &head_flag);
                if (head_ref && (head_flag & REF_ISSYMREF) &&
-                   !strcmp(head_ref, lock->ref_name))
-                       log_ref_write("HEAD", lock->old_oid.hash, sha1, logmsg);
+                   !strcmp(head_ref, lock->ref_name)) {
+                       struct strbuf log_err = STRBUF_INIT;
+                       if (log_ref_write("HEAD", lock->old_oid.hash, sha1,
+                                         logmsg, 0, &log_err)) {
+                               error("%s", log_err.buf);
+                               strbuf_release(&log_err);
+                       }
+               }
        }
        if (commit_ref(lock)) {
                error("Couldn't set %s", lock->ref_name);
                unlock_ref(lock);
                return -1;
        }
+
        unlock_ref(lock);
        return 0;
 }
@@ -3326,6 +3383,7 @@ int create_symref(const char *ref_target, const char *refs_heads_master,
        int fd, len, written;
        char *git_HEAD = git_pathdup("%s", ref_target);
        unsigned char old_sha1[20], new_sha1[20];
+       struct strbuf err = STRBUF_INIT;
 
        if (logmsg && read_ref(ref_target, old_sha1))
                hashclr(old_sha1);
@@ -3374,8 +3432,11 @@ int create_symref(const char *ref_target, const char *refs_heads_master,
 #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);
+       if (logmsg && !read_ref(refs_heads_master, new_sha1) &&
+               log_ref_write(ref_target, old_sha1, new_sha1, logmsg, 0, &err)) {
+               error("%s", err.buf);
+               strbuf_release(&err);
+       }
 
        free(git_HEAD);
        return 0;
@@ -3426,14 +3487,14 @@ static int read_ref_at_ent(unsigned char *osha1, unsigned char *nsha1,
                        hashcpy(cb->sha1, nsha1);
                        if (hashcmp(cb->osha1, nsha1))
                                warning("Log for ref %s has gap after %s.",
-                                       cb->refname, show_date(cb->date, cb->tz, DATE_RFC2822));
+                                       cb->refname, show_date(cb->date, cb->tz, DATE_MODE(RFC2822)));
                }
                else if (cb->date == cb->at_time)
                        hashcpy(cb->sha1, nsha1);
                else if (hashcmp(nsha1, cb->sha1))
                        warning("Log for ref %s unexpectedly ended on %s.",
                                cb->refname, show_date(cb->date, cb->tz,
-                                                  DATE_RFC2822));
+                                                      DATE_MODE(RFC2822)));
                hashcpy(cb->osha1, osha1);
                hashcpy(cb->nsha1, nsha1);
                cb->found_it = 1;
@@ -4011,14 +4072,19 @@ int ref_transaction_commit(struct ref_transaction *transaction,
                                 * value, so we don't need to write it.
                                 */
                        } else if (write_ref_to_lockfile(update->lock,
-                                                        update->new_sha1)) {
+                                                        update->new_sha1,
+                                                        err)) {
+                               char *write_err = strbuf_detach(err, NULL);
+
                                /*
                                 * The lock was freed upon failure of
                                 * write_ref_to_lockfile():
                                 */
                                update->lock = NULL;
-                               strbuf_addf(err, "cannot update the ref '%s'.",
-                                           update->refname);
+                               strbuf_addf(err,
+                                           "cannot update the ref '%s': %s",
+                                           update->refname, write_err);
+                               free(write_err);
                                ret = TRANSACTION_GENERIC_ERROR;
                                goto cleanup;
                        } else {
@@ -4044,11 +4110,10 @@ int ref_transaction_commit(struct ref_transaction *transaction,
 
                if (update->flags & REF_NEEDS_COMMIT) {
                        if (commit_ref_update(update->lock,
-                                             update->new_sha1, update->msg)) {
+                                             update->new_sha1, update->msg,
+                                             update->flags, err)) {
                                /* freed by commit_ref_update(): */
                                update->lock = NULL;
-                               strbuf_addf(err, "Cannot update the ref '%s'.",
-                                           update->refname);
                                ret = TRANSACTION_GENERIC_ERROR;
                                goto cleanup;
                        } else {
@@ -4093,9 +4158,19 @@ int ref_transaction_commit(struct ref_transaction *transaction,
        return ret;
 }
 
+static int ref_present(const char *refname,
+                      const struct object_id *oid, int flags, void *cb_data)
+{
+       struct string_list *affected_refnames = cb_data;
+
+       return string_list_has_string(affected_refnames, refname);
+}
+
 int initial_ref_transaction_commit(struct ref_transaction *transaction,
                                   struct strbuf *err)
 {
+       struct ref_dir *loose_refs = get_loose_refs(&ref_cache);
+       struct ref_dir *packed_refs = get_packed_refs(&ref_cache);
        int ret = 0, i;
        int n = transaction->nr;
        struct ref_update **updates = transaction->updates;
@@ -4115,12 +4190,36 @@ int initial_ref_transaction_commit(struct ref_transaction *transaction,
                goto cleanup;
        }
 
+       /*
+        * It's really undefined to call this function in an active
+        * repository or when there are existing references: we are
+        * only locking and changing packed-refs, so (1) any
+        * simultaneous processes might try to change a reference at
+        * the same time we do, and (2) any existing loose versions of
+        * the references that we are setting would have precedence
+        * over our values. But some remote helpers create the remote
+        * "HEAD" and "master" branches before calling this function,
+        * so here we really only check that none of the references
+        * that we are creating already exists.
+        */
+       if (for_each_rawref(ref_present, &affected_refnames))
+               die("BUG: initial ref transaction called with existing refs");
+
        for (i = 0; i < n; i++) {
                struct ref_update *update = updates[i];
 
                if ((update->flags & REF_HAVE_OLD) &&
                    !is_null_sha1(update->old_sha1))
                        die("BUG: initial ref transaction with old_sha1 set");
+               if (verify_refname_available(update->refname,
+                                            &affected_refnames, NULL,
+                                            loose_refs, err) ||
+                   verify_refname_available(update->refname,
+                                            &affected_refnames, NULL,
+                                            packed_refs, err)) {
+                       ret = TRANSACTION_NAME_CONFLICT;
+                       goto cleanup;
+               }
        }
 
        if (lock_packed_refs(0)) {