refs.c: rework ref_locks by abstracting from underlying struct lock_file

diff --git a/refs.c b/refs.c
index 58f6d173970bcd3c1e540b7cff04d1613fce3692..67d2a502afb60050f0ce750c21ae1a42fa5cb803 100644 (file)
--- a/refs.c
+++ b/refs.c
@@ -864,7 +864,6 @@ static int repack_without_ref(const char *refname)
                        die("too long a refname '%s'", list->name);
                write_or_die(fd, line, len);
        }
-       close(fd);
        return commit_lock_file(&packlock);
 }
 
@@ -1019,14 +1018,27 @@ int rename_ref(const char *oldref, const char *newref, const char *logmsg)
        return 1;
 }
 
+static int close_ref(struct ref_lock *lock)
+{
+       if (close_lock_file(lock->lk))
+               return -1;
+       lock->lock_fd = -1;
+       return 0;
+}
+
+static 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)
 {
-       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);
-       }
+       /* 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);
@@ -1119,10 +1131,16 @@ static int log_ref_write(const char *ref_name, const unsigned char *old_sha1,
        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;
@@ -1130,9 +1148,22 @@ int write_ref_sha1(struct ref_lock *lock,
                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(lock->lock_fd) < 0) {
+               || close_ref(lock) < 0) {
                error("Couldn't write %s", lock->lk->filename);
                unlock_ref(lock);
                return -1;
@@ -1165,12 +1196,11 @@ int write_ref_sha1(struct ref_lock *lock,
                    !strcmp(head_ref, lock->ref_name))
                        log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);
        }
-       if (commit_lock_file(lock->lk)) {
+       if (commit_ref(lock)) {
                error("Couldn't set %s", lock->ref_name);
                unlock_ref(lock);
                return -1;
        }
-       lock->lock_fd = -1;
        unlock_ref(lock);
        return 0;
 }