git-mv: fully detect 'directory moved into itself'

diff --git a/pack-objects.c b/pack-objects.c
index b3e61520339231f6d9a43c545100f4d5f87e0aac..8864a31cc14f4c57fe0115a0bfe73904fdb1ae12 100644 (file)
--- a/pack-objects.c
+++ b/pack-objects.c
@@ -400,6 +400,71 @@ static void find_deltas(struct object_entry **list, int window, int depth)
        free(array);
 }
 
+static void prepare_pack(int window, int depth)
+{
+       get_object_details();
+
+       fprintf(stderr, "Packing %d objects\n", nr_objects);
+
+       sorted_by_type = create_sorted_list(type_size_sort);
+       if (window && depth)
+               find_deltas(sorted_by_type, window+1, depth);
+       write_pack_file();
+}
+
+static int reuse_cached_pack(unsigned char *sha1, int pack_to_stdout)
+{
+       static const char cache[] = "pack-cache/pack-%s.%s";
+       char *cached_pack, *cached_idx;
+       int ifd, ofd, ifd_ix = -1;
+
+       cached_pack = git_path(cache, sha1_to_hex(sha1), "pack");
+       ifd = open(cached_pack, O_RDONLY);
+       if (ifd < 0)
+               return 0;
+
+       if (!pack_to_stdout) {
+               cached_idx = git_path(cache, sha1_to_hex(sha1), "idx");
+               ifd_ix = open(cached_idx, O_RDONLY);
+               if (ifd_ix < 0) {
+                       close(ifd);
+                       return 0;
+               }
+       }
+
+       fprintf(stderr, "Reusing %d objects pack %s\n", nr_objects,
+               sha1_to_hex(sha1));
+
+       if (pack_to_stdout) {
+               if (copy_fd(ifd, 1))
+                       exit(1);
+               close(ifd);
+       }
+       else {
+               char name[PATH_MAX];
+               snprintf(name, sizeof(name),
+                        "%s-%s.%s", base_name, sha1_to_hex(sha1), "pack");
+               ofd = open(name, O_CREAT | O_EXCL | O_WRONLY, 0666);
+               if (ofd < 0)
+                       die("unable to open %s (%s)", name, strerror(errno));
+               if (copy_fd(ifd, ofd))
+                       exit(1);
+               close(ifd);
+
+               snprintf(name, sizeof(name),
+                        "%s-%s.%s", base_name, sha1_to_hex(sha1), "idx");
+               ofd = open(name, O_CREAT | O_EXCL | O_WRONLY, 0666);
+               if (ofd < 0)
+                       die("unable to open %s (%s)", name, strerror(errno));
+               if (copy_fd(ifd_ix, ofd))
+                       exit(1);
+               close(ifd_ix);
+               puts(sha1_to_hex(sha1));
+       }
+
+       return 1;
+}
+
 int main(int argc, char **argv)
 {
        SHA_CTX ctx;
@@ -459,7 +524,7 @@ int main(int argc, char **argv)
                unsigned char sha1[20];
 
                if (get_sha1_hex(line, sha1))
-                       die("expected sha1, got garbage");
+                       die("expected sha1, got garbage:\n %s", line);
                hash = 0;
                p = line+40;
                while (*p) {
@@ -472,9 +537,6 @@ int main(int argc, char **argv)
        }
        if (non_empty && !nr_objects)
                return 0;
-       get_object_details();
-
-       fprintf(stderr, "Packing %d objects\n", nr_objects);
 
        sorted_by_sha = create_sorted_list(sha1_sort);
        SHA1_Init(&ctx);
@@ -485,14 +547,14 @@ int main(int argc, char **argv)
        }
        SHA1_Final(object_list_sha1, &ctx);
 
-       sorted_by_type = create_sorted_list(type_size_sort);
-       if (window && depth)
-               find_deltas(sorted_by_type, window+1, depth);
-
-       write_pack_file();
-       if (!pack_to_stdout) {
-               write_index_file();
-               puts(sha1_to_hex(object_list_sha1));
+       if (reuse_cached_pack(object_list_sha1, pack_to_stdout))
+               ;
+       else {
+               prepare_pack(window, depth);
+               if (!pack_to_stdout) {
+                       write_index_file();
+                       puts(sha1_to_hex(object_list_sha1));
+               }
        }
        return 0;
 }