Teach send-pack a mirror mode

Existing "git push --all" is almost perfect for backing up to
another repository, except that "--all" only means "all
branches" in modern git, and it does not delete old branches and
tags that exist at the back-up repository that you have removed
from your local repository.

This teaches "git-send-pack" a new "--mirror" option.  The
difference from the "--all" option are that (1) it sends all
refs, not just branches, and (2) it deletes old refs you no
longer have on the local side from the remote side.

Original patch by Junio C Hamano.

Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/builtin-send-pack.c b/builtin-send-pack.c
index 5a0f5c681cb1141576564972c4ad3f7999a1ff27..d42164ec085a4843fb52ee8ed9d04c47e3c09db0 100644 (file)
--- a/builtin-send-pack.c
+++ b/builtin-send-pack.c
@@ -8,7 +8,7 @@
 #include "send-pack.h"
 
 static const char send_pack_usage[] =
-"git-send-pack [--all] [--dry-run] [--force] [--receive-pack=<git-receive-pack>] [--verbose] [--thin] [<host>:]<directory> [<ref>...]\n"
+"git-send-pack [--all | --mirror] [--dry-run] [--force] [--receive-pack=<git-receive-pack>] [--verbose] [--thin] [<host>:]<directory> [<ref>...]\n"
 "  --all and explicit <ref> specification are mutually exclusive.";
 
 static struct send_pack_args args = {
@@ -227,6 +227,12 @@ static int do_send_pack(int in, int out, struct remote *remote, const char *dest
        int allow_deleting_refs = 0;
        int expect_status_report = 0;
        int shown_dest = 0;
+       int flags = MATCH_REFS_NONE;
+
+       if (args.send_all)
+               flags |= MATCH_REFS_ALL;
+       if (args.send_mirror)
+               flags |= MATCH_REFS_MIRROR;
 
        /* No funny business with the matcher */
        remote_tail = get_remote_heads(in, &remote_refs, 0, NULL, REF_NORMAL);
@@ -242,7 +248,7 @@ static int do_send_pack(int in, int out, struct remote *remote, const char *dest
        if (!remote_tail)
                remote_tail = &remote_refs;
        if (match_refs(local_refs, remote_refs, &remote_tail,
-                      nr_refspec, refspec, args.send_all))
+                                              nr_refspec, refspec, flags))
                return -1;
 
        if (!remote_refs) {
@@ -259,20 +265,28 @@ static int do_send_pack(int in, int out, struct remote *remote, const char *dest
                char old_hex[60], *new_hex;
                int will_delete_ref;
                const char *pretty_ref;
-               const char *pretty_peer;
+               const char *pretty_peer = NULL; /* only used when not deleting */
+               const unsigned char *new_sha1;
 
-               if (!ref->peer_ref)
-                       continue;
+               if (!ref->peer_ref) {
+                       if (!args.send_mirror)
+                               continue;
+                       new_sha1 = null_sha1;
+               }
+               else
+                       new_sha1 = ref->peer_ref->new_sha1;
 
                if (!shown_dest) {
                        fprintf(stderr, "To %s\n", dest);
                        shown_dest = 1;
                }
 
+               will_delete_ref = is_null_sha1(new_sha1);
+
                pretty_ref = prettify_ref(ref->name);
-               pretty_peer = prettify_ref(ref->peer_ref->name);
+               if (!will_delete_ref)
+                       pretty_peer = prettify_ref(ref->peer_ref->name);
 
-               will_delete_ref = is_null_sha1(ref->peer_ref->new_sha1);
                if (will_delete_ref && !allow_deleting_refs) {
                        fprintf(stderr, " ! %-*s %s (remote does not support deleting refs)\n",
                                        SUMMARY_WIDTH, "[rejected]", pretty_ref);
@@ -280,7 +294,7 @@ static int do_send_pack(int in, int out, struct remote *remote, const char *dest
                        continue;
                }
                if (!will_delete_ref &&
-                   !hashcmp(ref->old_sha1, ref->peer_ref->new_sha1)) {
+                   !hashcmp(ref->old_sha1, new_sha1)) {
                        if (args.verbose)
                                fprintf(stderr, " = %-*s %s -> %s\n",
                                        SUMMARY_WIDTH, "[up to date]",
@@ -312,8 +326,7 @@ static int do_send_pack(int in, int out, struct remote *remote, const char *dest
                    !is_null_sha1(ref->old_sha1) &&
                    !ref->force) {
                        if (!has_sha1_file(ref->old_sha1) ||
-                           !ref_newer(ref->peer_ref->new_sha1,
-                                      ref->old_sha1)) {
+                           !ref_newer(new_sha1, ref->old_sha1)) {
                                /* We do not have the remote ref, or
                                 * we know that the remote ref is not
                                 * an ancestor of what we are trying to
@@ -328,7 +341,7 @@ static int do_send_pack(int in, int out, struct remote *remote, const char *dest
                                continue;
                        }
                }
-               hashcpy(ref->new_sha1, ref->peer_ref->new_sha1);
+               hashcpy(ref->new_sha1, new_sha1);
                if (!will_delete_ref)
                        new_refs++;
                strcpy(old_hex, sha1_to_hex(ref->old_sha1));
@@ -459,6 +472,10 @@ int cmd_send_pack(int argc, const char **argv, const char *prefix)
                                args.dry_run = 1;
                                continue;
                        }
+                       if (!strcmp(arg, "--mirror")) {
+                               args.send_mirror = 1;
+                               continue;
+                       }
                        if (!strcmp(arg, "--force")) {
                                args.force_update = 1;
                                continue;
@@ -483,7 +500,12 @@ int cmd_send_pack(int argc, const char **argv, const char *prefix)
        }
        if (!dest)
                usage(send_pack_usage);
-       if (heads && args.send_all)
+       /*
+        * --all and --mirror are incompatible; neither makes sense
+        * with any refspecs.
+        */
+       if ((heads && (args.send_all || args.send_mirror)) ||
+                                       (args.send_all && args.send_mirror))
                usage(send_pack_usage);
 
        if (remote_name) {

diff --git a/http-push.c b/http-push.c
index 99328f5909d4db247fa2453df9ac14cde0c61c9a..66b81f17266569ee47d32ec58df9d1386e4d0431 100644 (file)
--- a/http-push.c
+++ b/http-push.c
@@ -78,7 +78,7 @@ static struct curl_slist *no_pragma_header;
 static struct curl_slist *default_headers;
 
 static int push_verbosely;
-static int push_all;
+static int push_all = MATCH_REFS_NONE;
 static int force_all;
 static int dry_run;
 
@@ -2300,7 +2300,7 @@ int main(int argc, char **argv)
 
                if (*arg == '-') {
                        if (!strcmp(arg, "--all")) {
-                               push_all = 1;
+                               push_all = MATCH_REFS_ALL;
                                continue;
                        }
                        if (!strcmp(arg, "--force")) {

diff --git a/remote.c b/remote.c
index 59defdbf1460b5c476364f611cf212cf90f567e3..09b7aad525e5916ea46d35b6ea253f716b2a2d85 100644 (file)
--- a/remote.c
+++ b/remote.c
@@ -722,10 +722,12 @@ static const struct refspec *check_pattern_match(const struct refspec *rs,
  * without thinking.
  */
 int match_refs(struct ref *src, struct ref *dst, struct ref ***dst_tail,
-              int nr_refspec, const char **refspec, int all)
+              int nr_refspec, const char **refspec, int flags)
 {
        struct refspec *rs =
                parse_ref_spec(nr_refspec, (const char **) refspec);
+       int send_all = flags & MATCH_REFS_ALL;
+       int send_mirror = flags & MATCH_REFS_MIRROR;
 
        if (match_explicit_refs(src, dst, dst_tail, rs, nr_refspec))
                return -1;
@@ -742,7 +744,7 @@ int match_refs(struct ref *src, struct ref *dst, struct ref ***dst_tail,
                        if (!pat)
                                continue;
                }
-               else if (prefixcmp(src->name, "refs/heads/"))
+               else if (!send_mirror && prefixcmp(src->name, "refs/heads/"))
                        /*
                         * "matching refs"; traditionally we pushed everything
                         * including refs outside refs/heads/ hierarchy, but
@@ -763,10 +765,13 @@ int match_refs(struct ref *src, struct ref *dst, struct ref ***dst_tail,
                if (dst_peer && dst_peer->peer_ref)
                        /* We're already sending something to this ref. */
                        goto free_name;
-               if (!dst_peer && !nr_refspec && !all)
-                       /* Remote doesn't have it, and we have no
+
+               if (!dst_peer && !nr_refspec && !(send_all || send_mirror))
+                       /*
+                        * Remote doesn't have it, and we have no
                         * explicit pattern, and we don't have
-                        * --all. */
+                        * --all nor --mirror.
+                        */
                        goto free_name;
                if (!dst_peer) {
                        /* Create a new one and link it */

diff --git a/remote.h b/remote.h
index 6a4c7a0f37720a41d70ee4099d6e91c31ab69375..b10036cae6f89e087da56979e2248e1e5c5d42d3 100644 (file)
--- a/remote.h
+++ b/remote.h
@@ -102,4 +102,11 @@ struct branch *branch_get(const char *name);
 int branch_has_merge_config(struct branch *branch);
 int branch_merge_matches(struct branch *, int n, const char *);
 
+/* Flags to match_refs. */
+enum match_refs_flags {
+       MATCH_REFS_NONE         = 0,
+       MATCH_REFS_ALL          = (1 << 0),
+       MATCH_REFS_MIRROR       = (1 << 1),
+};
+
 #endif

diff --git a/send-pack.h b/send-pack.h
index 7a24f71c77b1a1d700171bdf088a3c3c7527c6ae..8ff1dc35390083c3648c4ee5790f35633d956069 100644 (file)
--- a/send-pack.h
+++ b/send-pack.h
@@ -5,6 +5,7 @@ struct send_pack_args {
        const char *receivepack;
        unsigned verbose:1,
                send_all:1,
+               send_mirror:1,
                force_update:1,
                use_thin_pack:1,
                dry_run:1;