Fix send-pack for non-commitish tags.

[git.git] / send-pack.c

diff --git a/send-pack.c b/send-pack.c
index 633fc47..4d015fd 100644 (file)
--- a/send-pack.c
+++ b/send-pack.c
@@ -1,5 +1,6 @@
 #include "cache.h"
 #include "commit.h"
+#include "tag.h"
 #include "refs.h"
 #include "pkt-line.h"
 
@@ -104,19 +105,26 @@ static int pack_objects(int fd, struct ref *refs)
        return 0;
 }
 
-static int ref_newer(const unsigned char *new_sha1, const unsigned char *old_sha1)
+static int ref_newer(const unsigned char *new_sha1,
+                    const unsigned char *old_sha1)
 {
-       struct commit *new, *old;
+       struct object *o;
+       struct commit *old, *new;
        struct commit_list *list;
 
-       if (force_update)
-               return 1;
-       old = lookup_commit_reference(old_sha1);
-       if (!old)
+       /* Both new and old must be commit-ish and new is descendant of
+        * old.  Otherwise we require --force.
+        */
+       o = deref_tag(parse_object(old_sha1));
+       if (!o || o->type != commit_type)
                return 0;
-       new = lookup_commit_reference(new_sha1);
-       if (!new)
+       old = (struct commit *) o;
+
+       o = deref_tag(parse_object(new_sha1));
+       if (!o || o->type != commit_type)
                return 0;
+       new = (struct commit *) o;
+
        if (parse_commit(new) < 0)
                return 0;
        list = NULL;
@@ -173,13 +181,38 @@ static int send_pack(int in, int out, int nr_refspec, char **refspec)
                char old_hex[60], *new_hex;
                if (!ref->peer_ref)
                        continue;
-               if (!is_zero_sha1(ref->old_sha1)) {
+               if (!memcmp(ref->old_sha1, ref->peer_ref->new_sha1, 20)) {
+                       fprintf(stderr, "'%s': up-to-date\n", ref->name);
+                       continue;
+               }
+
+               /* This part determines what can overwrite what.
+                * The rules are:
+                *
+                * (0) you can always use --force.
+                *
+                * (1) if the old thing does not exist, it is OK.
+                *
+                * (2) if you do not have the old thing, you are not allowed
+                *     to overwrite it; you would not know what you are losing
+                *     otherwise.
+                *
+                * (3) if both new and old are commit-ish, and new is a
+                *     descendant of old, it is OK.
+                */
+
+               if (!force_update && !is_zero_sha1(ref->old_sha1)) {
                        if (!has_sha1_file(ref->old_sha1)) {
                                error("remote '%s' object %s does not "
                                      "exist on local",
                                      ref->name, sha1_to_hex(ref->old_sha1));
                                continue;
                        }
+                       /* We assume that local is fsck-clean.  Otherwise
+                        * you _could_ have a old tag which points at
+                        * something you do not have which may or may not
+                        * be a commit.
+                        */
                        if (!ref_newer(ref->peer_ref->new_sha1,
                                       ref->old_sha1)) {
                                error("remote ref '%s' is not a strict "
@@ -188,10 +221,6 @@ static int send_pack(int in, int out, int nr_refspec, char **refspec)
                                continue;
                        }
                }
-               if (!memcmp(ref->old_sha1, ref->peer_ref->new_sha1, 20)) {
-                       fprintf(stderr, "'%s': up-to-date\n", ref->name);
-                       continue;
-               }
                memcpy(ref->new_sha1, ref->peer_ref->new_sha1, 20);
                if (is_zero_sha1(ref->new_sha1)) {
                        error("cannot happen anymore");