fsck-cache: walk the 'refs' directory if the user doesn't give any

diff --git a/fsck-cache.c b/fsck-cache.c
index a00702b79f7169ef3da7d60e9bbbe9ccf237e673..d2aff8c64380f5655ea14de9f6f6e4ce468e525a 100644 (file)
--- a/fsck-cache.c
+++ b/fsck-cache.c
@@ -296,6 +296,70 @@ static int fsck_dir(int i, char *path)
        return 0;
 }
 
+static void read_sha1_reference(const char *path)
+{
+       char hexname[60];
+       unsigned char sha1[20];
+       int fd = open(path, O_RDONLY), len;
+       struct object *obj;
+
+       if (fd < 0)
+               return;
+
+       len = read(fd, hexname, sizeof(hexname));
+       close(fd);
+       if (len < 40)
+               return;
+
+       if (get_sha1_hex(hexname, sha1) < 0)
+               return;
+
+       obj = lookup_object(sha1);
+       obj->used = 1;
+       mark_reachable(obj, REACHABLE);
+}
+
+static void find_file_objects(const char *base, const char *name)
+{
+       int baselen = strlen(base);
+       int namelen = strlen(name);
+       char *path = xmalloc(baselen + namelen + 2);
+       struct stat st;
+
+       memcpy(path, base, baselen);
+       path[baselen] = '/';
+       memcpy(path + baselen + 1, name, namelen+1);
+       if (stat(path, &st) < 0)
+               return;
+
+       /*
+        * Recurse into directories
+        */
+       if (S_ISDIR(st.st_mode)) {
+               DIR *dir = opendir(path);
+               if (dir) {
+                       struct dirent *de;
+                       while ((de = readdir(dir)) != NULL) {
+                               if (de->d_name[0] == '.')
+                                       continue;
+                               find_file_objects(path, de->d_name);
+                       }
+                       closedir(dir);
+               }
+               return;
+       }
+       if (S_ISREG(st.st_mode)) {
+               read_sha1_reference(path);
+               return;
+       }
+}
+
+static void get_default_heads(void)
+{
+       char *git_dir = gitenv(GIT_DIR_ENVIRONMENT) ? : DEFAULT_GIT_DIR_ENVIRONMENT;
+       find_file_objects(git_dir, "refs");
+}
+
 int main(int argc, char **argv)
 {
        int i, heads;
@@ -354,6 +418,16 @@ int main(int argc, char **argv)
                error("expected sha1, got %s", arg);
        }
 
+       /*
+        * If we've been asked to do reachability without any explicit
+        * head information, do the default ones from .git/refs. We also
+        * consider the index file in this case (ie this implies --cache).
+        */
+       if (show_unreachable && !heads) {
+               get_default_heads();
+               keep_cache_objects = 1;
+       }
+
        if (keep_cache_objects) {
                int i;
                read_cache();
@@ -368,15 +442,6 @@ int main(int argc, char **argv)
                }
        }
 
-       if (!heads && !keep_cache_objects) {
-               if (show_unreachable) {
-                       fprintf(stderr, "unable to do reachability without a head nor --cache\n");
-                       show_unreachable = 0; 
-               }
-               if (!heads)
-                       fprintf(stderr, "expect dangling commits - potential heads - due to lack of head information\n");
-       }
-
        check_connectivity();
        return 0;
 }