t5533: test "push --force-with-lease"
[gitweb.git] / remote.c
index e71f66de25b6031bbe1ee94ab3770aacd15b46e0..922822c3cb5ac383045ee0edcc5ade6731e2e018 100644 (file)
--- a/remote.c
+++ b/remote.c
@@ -276,10 +276,9 @@ static void read_remotes_file(struct remote *remote)
 
 static void read_branches_file(struct remote *remote)
 {
-       const char *slash = strchr(remote->name, '/');
        char *frag;
        struct strbuf branch = STRBUF_INIT;
-       int n = slash ? slash - remote->name : 1000;
+       int n = 1000;
        FILE *f = fopen(git_path("branches/%.*s", n, remote->name), "r");
        char *s, *p;
        int len;
@@ -299,21 +298,11 @@ static void read_branches_file(struct remote *remote)
        while (isspace(p[-1]))
                *--p = 0;
        len = p - s;
-       if (slash)
-               len += strlen(slash);
        p = xmalloc(len + 1);
        strcpy(p, s);
-       if (slash)
-               strcat(p, slash);
 
        /*
-        * With "slash", e.g. "git fetch jgarzik/netdev-2.6" when
-        * reading from $GIT_DIR/branches/jgarzik fetches "HEAD" from
-        * the partial URL obtained from the branches file plus
-        * "/netdev-2.6" and does not store it in any tracking ref.
-        * #branch specifier in the file is ignored.
-        *
-        * Otherwise, the branches file would have URL and optionally
+        * The branches file would have URL and optionally
         * #branch specified.  The "master" (or specified) branch is
         * fetched and stored in the local branch of the same name.
         */
@@ -323,12 +312,8 @@ static void read_branches_file(struct remote *remote)
                strbuf_addf(&branch, "refs/heads/%s", frag);
        } else
                strbuf_addstr(&branch, "refs/heads/master");
-       if (!slash) {
-               strbuf_addf(&branch, ":refs/heads/%s", remote->name);
-       } else {
-               strbuf_reset(&branch);
-               strbuf_addstr(&branch, "HEAD:");
-       }
+
+       strbuf_addf(&branch, ":refs/heads/%s", remote->name);
        add_url_alias(remote, p);
        add_fetch_refspec(remote, strbuf_detach(&branch, NULL));
        /*
@@ -1317,6 +1302,14 @@ static void add_missing_tags(struct ref *src, struct ref **dst, struct ref ***ds
        free(sent_tips.tip);
 }
 
+struct ref *find_ref_by_name(const struct ref *list, const char *name)
+{
+       for ( ; list; list = list->next)
+               if (!strcmp(list->name, name))
+                       return (struct ref *)list;
+       return NULL;
+}
+
 /*
  * Given the set of refs the local repository has, the set of refs the
  * remote repository has, and the refspec used for push, determine
@@ -1403,12 +1396,13 @@ int match_push_refs(struct ref *src, struct ref **dst,
 }
 
 void set_ref_status_for_push(struct ref *remote_refs, int send_mirror,
-       int force_update)
+                            int force_update)
 {
        struct ref *ref;
 
        for (ref = remote_refs; ref; ref = ref->next) {
                int force_ref_update = ref->force || force_update;
+               int reject_reason = 0;
 
                if (ref->peer_ref)
                        hashcpy(ref->new_sha1, ref->peer_ref->new_sha1);
@@ -1423,6 +1417,26 @@ void set_ref_status_for_push(struct ref *remote_refs, int send_mirror,
                }
 
                /*
+                * Bypass the usual "must fast-forward" check but
+                * replace it with a weaker "the old value must be
+                * this value we observed".  If the remote ref has
+                * moved and is now different from what we expect,
+                * reject any push.
+                *
+                * It also is an error if the user told us to check
+                * with the remote-tracking branch to find the value
+                * to expect, but we did not have such a tracking
+                * branch.
+                */
+               if (ref->expect_old_sha1) {
+                       if (ref->expect_old_no_trackback ||
+                           hashcmp(ref->old_sha1, ref->old_sha1_expect))
+                               reject_reason = REF_STATUS_REJECT_STALE;
+               }
+
+               /*
+                * The usual "must fast-forward" rules.
+                *
                 * Decide whether an individual refspec A:B can be
                 * pushed.  The push will succeed if any of the
                 * following are true:
@@ -1440,24 +1454,26 @@ void set_ref_status_for_push(struct ref *remote_refs, int send_mirror,
                 *     passing the --force argument
                 */
 
-               if (!ref->deletion && !is_null_sha1(ref->old_sha1)) {
-                       int why = 0; /* why would this push require --force? */
-
+               else if (!ref->deletion && !is_null_sha1(ref->old_sha1)) {
                        if (!prefixcmp(ref->name, "refs/tags/"))
-                               why = REF_STATUS_REJECT_ALREADY_EXISTS;
+                               reject_reason = REF_STATUS_REJECT_ALREADY_EXISTS;
                        else if (!has_sha1_file(ref->old_sha1))
-                               why = REF_STATUS_REJECT_FETCH_FIRST;
+                               reject_reason = REF_STATUS_REJECT_FETCH_FIRST;
                        else if (!lookup_commit_reference_gently(ref->old_sha1, 1) ||
                                 !lookup_commit_reference_gently(ref->new_sha1, 1))
-                               why = REF_STATUS_REJECT_NEEDS_FORCE;
+                               reject_reason = REF_STATUS_REJECT_NEEDS_FORCE;
                        else if (!ref_newer(ref->new_sha1, ref->old_sha1))
-                               why = REF_STATUS_REJECT_NONFASTFORWARD;
-
-                       if (!force_ref_update)
-                               ref->status = why;
-                       else if (why)
-                               ref->forced_update = 1;
+                               reject_reason = REF_STATUS_REJECT_NONFASTFORWARD;
                }
+
+               /*
+                * "--force" will defeat any rejection implemented
+                * by the rules above.
+                */
+               if (!force_ref_update)
+                       ref->status = reject_reason;
+               else if (reject_reason)
+                       ref->forced_update = 1;
        }
 }
 
@@ -1928,3 +1944,121 @@ struct ref *get_stale_heads(struct refspec *refs, int ref_count, struct ref *fet
        string_list_clear(&ref_names, 0);
        return stale_refs;
 }
+
+/*
+ * Compare-and-swap
+ */
+void clear_cas_option(struct push_cas_option *cas)
+{
+       int i;
+
+       for (i = 0; i < cas->nr; i++)
+               free(cas->entry[i].refname);
+       free(cas->entry);
+       memset(cas, 0, sizeof(*cas));
+}
+
+static struct push_cas *add_cas_entry(struct push_cas_option *cas,
+                                     const char *refname,
+                                     size_t refnamelen)
+{
+       struct push_cas *entry;
+       ALLOC_GROW(cas->entry, cas->nr + 1, cas->alloc);
+       entry = &cas->entry[cas->nr++];
+       memset(entry, 0, sizeof(*entry));
+       entry->refname = xmemdupz(refname, refnamelen);
+       return entry;
+}
+
+int parse_push_cas_option(struct push_cas_option *cas, const char *arg, int unset)
+{
+       const char *colon;
+       struct push_cas *entry;
+
+       if (unset) {
+               /* "--no-<option>" */
+               clear_cas_option(cas);
+               return 0;
+       }
+
+       if (!arg) {
+               /* just "--<option>" */
+               cas->use_tracking_for_rest = 1;
+               return 0;
+       }
+
+       /* "--<option>=refname" or "--<option>=refname:value" */
+       colon = strchrnul(arg, ':');
+       entry = add_cas_entry(cas, arg, colon - arg);
+       if (!*colon)
+               entry->use_tracking = 1;
+       else if (get_sha1(colon + 1, entry->expect))
+               return error("cannot parse expected object name '%s'", colon + 1);
+       return 0;
+}
+
+int parseopt_push_cas_option(const struct option *opt, const char *arg, int unset)
+{
+       return parse_push_cas_option(opt->value, arg, unset);
+}
+
+int is_empty_cas(const struct push_cas_option *cas)
+{
+       return !cas->use_tracking_for_rest && !cas->nr;
+}
+
+/*
+ * Look at remote.fetch refspec and see if we have a remote
+ * tracking branch for the refname there.  Fill its current
+ * value in sha1[].
+ * If we cannot do so, return negative to signal an error.
+ */
+static int remote_tracking(struct remote *remote, const char *refname,
+                          unsigned char sha1[20])
+{
+       char *dst;
+
+       dst = apply_refspecs(remote->fetch, remote->fetch_refspec_nr, refname);
+       if (!dst)
+               return -1; /* no tracking ref for refname at remote */
+       if (read_ref(dst, sha1))
+               return -1; /* we know what the tracking ref is but we cannot read it */
+       return 0;
+}
+
+static void apply_cas(struct push_cas_option *cas,
+                     struct remote *remote,
+                     struct ref *ref)
+{
+       int i;
+
+       /* Find an explicit --<option>=<name>[:<value>] entry */
+       for (i = 0; i < cas->nr; i++) {
+               struct push_cas *entry = &cas->entry[i];
+               if (!refname_match(entry->refname, ref->name, ref_rev_parse_rules))
+                       continue;
+               ref->expect_old_sha1 = 1;
+               if (!entry->use_tracking)
+                       hashcpy(ref->old_sha1_expect, cas->entry[i].expect);
+               else if (remote_tracking(remote, ref->name, ref->old_sha1_expect))
+                       ref->expect_old_no_trackback = 1;
+               return;
+       }
+
+       /* Are we using "--<option>" to cover all? */
+       if (!cas->use_tracking_for_rest)
+               return;
+
+       ref->expect_old_sha1 = 1;
+       if (remote_tracking(remote, ref->name, ref->old_sha1_expect))
+               ref->expect_old_no_trackback = 1;
+}
+
+void apply_push_cas(struct push_cas_option *cas,
+                   struct remote *remote,
+                   struct ref *remote_refs)
+{
+       struct ref *ref;
+       for (ref = remote_refs; ref; ref = ref->next)
+               apply_cas(cas, remote, ref);
+}