cgit.c: use resolve_ref() to guess_defbranch()

The resolve_ref() function handles reading of git- and filesystem
symbolic links (including proper whitespace trimming) and packed refs.
There's no point in reimplementing this function in cgit.

Signed-off-by: Lars Hjemli <hjemli@gmail.com>

1 files changed, 7 insertions, 27 deletions

diff --git a/cgit.c b/cgit.c
index e3fbbf4..624cb2c 100644
--- a/cgit.c
+++ b/cgit.c
@@ -418,33 +418,13 @@ char *find_default_branch(struct cgit_repo *repo)
 
 static char *guess_defbranch(const char *repo_path)
 {
-        int fd, len;
-        char buffer[256];
-        char *ref_start;
-        char *head;
-
-        head = fmt("%s/HEAD", repo_path);
-        fd = open(head, O_RDONLY);
-        if (fd == -1)
-                return xstrdup("master");
-
-        memset(buffer, 0, sizeof(buffer));
-        len = read_in_full(fd, buffer, sizeof(buffer) - 1);
-        close(fd);
-
-        if(!memcmp(buffer, "ref: refs/heads/", 16))
-                return xstrndup(buffer + 16, len - 17);
-
-        if(strlen(buffer) == 41) {
-                /* probably contains a SHA1 sum */
-                memset(buffer, 0, sizeof(buffer));
-                if(readlink(head, buffer, sizeof(buffer)-1)) {
-                        ref_start = memmem(buffer, sizeof(buffer)-1, "refs/heads/", 11);
-                        if(ref_start)
-                                return xstrdup(ref_start+11);
-                }
-        }
-        return xstrdup("master");
+        const char *ref;
+        unsigned char sha1[20];
+
+        ref = resolve_ref("HEAD", sha1, 0, NULL);
+        if (!ref || prefixcmp(ref, "refs/heads/"))
+                return "master";
+        return xstrdup(ref + 11);
 }
 
 static int prepare_repo_cmd(struct cgit_context *ctx)