push: teach --force-with-lease to smart-http transport
[gitweb.git] / remote.c
index e53a6eb7769e2884f77819c73423c31e49b0114e..922822c3cb5ac383045ee0edcc5ade6731e2e018 100644 (file)
--- a/remote.c
+++ b/remote.c
@@ -15,6 +15,7 @@ static struct refspec s_tag_refspec = {
        0,
        1,
        0,
+       0,
        "refs/tags/*",
        "refs/tags/*"
 };
@@ -48,6 +49,7 @@ static int branches_nr;
 
 static struct branch *current_branch;
 static const char *default_remote_name;
+static const char *pushremote_name;
 static int explicit_default_remote_name;
 
 static struct rewrites rewrites;
@@ -274,10 +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;
@@ -297,21 +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.
         */
@@ -321,12 +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));
        /*
@@ -356,13 +343,16 @@ static int handle_config(const char *key, const char *value, void *cb)
                        return 0;
                branch = make_branch(name, subkey - name);
                if (!strcmp(subkey, ".remote")) {
-                       if (!value)
-                               return config_error_nonbool(key);
-                       branch->remote_name = xstrdup(value);
+                       if (git_config_string(&branch->remote_name, key, value))
+                               return -1;
                        if (branch == current_branch) {
                                default_remote_name = branch->remote_name;
                                explicit_default_remote_name = 1;
                        }
+               } else if (!strcmp(subkey, ".pushremote")) {
+                       if (branch == current_branch)
+                               if (git_config_string(&pushremote_name, key, value))
+                                       return -1;
                } else if (!strcmp(subkey, ".merge")) {
                        if (!value)
                                return config_error_nonbool(key);
@@ -388,9 +378,16 @@ static int handle_config(const char *key, const char *value, void *cb)
                        add_instead_of(rewrite, xstrdup(value));
                }
        }
+
        if (prefixcmp(key,  "remote."))
                return 0;
        name = key + 7;
+
+       /* Handle remote.* variables */
+       if (!strcmp(name, "pushdefault"))
+               return git_config_string(&pushremote_name, key, value);
+
+       /* Handle remote.<name>.* variables */
        if (*name == '/') {
                warning("Config remote shorthand cannot begin with '/': %s",
                        name);
@@ -538,7 +535,7 @@ static struct refspec *parse_refspec_internal(int nr_refspec, const char **refsp
 
                /*
                 * Before going on, special case ":" (or "+:") as a refspec
-                * for matching refs.
+                * for pushing matching refs.
                 */
                if (!fetch && rhs == lhs && rhs[1] == '\0') {
                        rs[i].matching = 1;
@@ -565,26 +562,25 @@ static struct refspec *parse_refspec_internal(int nr_refspec, const char **refsp
                flags = REFNAME_ALLOW_ONELEVEL | (is_glob ? REFNAME_REFSPEC_PATTERN : 0);
 
                if (fetch) {
-                       /*
-                        * LHS
-                        * - empty is allowed; it means HEAD.
-                        * - otherwise it must be a valid looking ref.
-                        */
+                       unsigned char unused[40];
+
+                       /* LHS */
                        if (!*rs[i].src)
-                               ; /* empty is ok */
-                       else if (check_refname_format(rs[i].src, flags))
+                               ; /* empty is ok; it means "HEAD" */
+                       else if (llen == 40 && !get_sha1_hex(rs[i].src, unused))
+                               rs[i].exact_sha1 = 1; /* ok */
+                       else if (!check_refname_format(rs[i].src, flags))
+                               ; /* valid looking ref is ok */
+                       else
                                goto invalid;
-                       /*
-                        * RHS
-                        * - missing is ok, and is same as empty.
-                        * - empty is ok; it means not to store.
-                        * - otherwise it must be a valid looking ref.
-                        */
+                       /* RHS */
                        if (!rs[i].dst)
-                               ; /* ok */
+                               ; /* missing is ok; it is the same as empty */
                        else if (!*rs[i].dst)
-                               ; /* ok */
-                       else if (check_refname_format(rs[i].dst, flags))
+                               ; /* empty is ok; it means "do not store" */
+                       else if (!check_refname_format(rs[i].dst, flags))
+                               ; /* valid looking ref is ok */
+                       else
                                goto invalid;
                } else {
                        /*
@@ -671,17 +667,21 @@ static int valid_remote_nick(const char *name)
        return !strchr(name, '/'); /* no slash */
 }
 
-struct remote *remote_get(const char *name)
+static struct remote *remote_get_1(const char *name, const char *pushremote_name)
 {
        struct remote *ret;
        int name_given = 0;
 
-       read_config();
        if (name)
                name_given = 1;
        else {
-               name = default_remote_name;
-               name_given = explicit_default_remote_name;
+               if (pushremote_name) {
+                       name = pushremote_name;
+                       name_given = 1;
+               } else {
+                       name = default_remote_name;
+                       name_given = explicit_default_remote_name;
+               }
        }
 
        ret = make_remote(name, 0);
@@ -700,6 +700,18 @@ struct remote *remote_get(const char *name)
        return ret;
 }
 
+struct remote *remote_get(const char *name)
+{
+       read_config();
+       return remote_get_1(name, NULL);
+}
+
+struct remote *pushremote_get(const char *name)
+{
+       read_config();
+       return remote_get_1(name, pushremote_name);
+}
+
 int remote_is_configured(const char *name)
 {
        int i;
@@ -1195,6 +1207,109 @@ static struct ref **tail_ref(struct ref **head)
        return tail;
 }
 
+struct tips {
+       struct commit **tip;
+       int nr, alloc;
+};
+
+static void add_to_tips(struct tips *tips, const unsigned char *sha1)
+{
+       struct commit *commit;
+
+       if (is_null_sha1(sha1))
+               return;
+       commit = lookup_commit_reference_gently(sha1, 1);
+       if (!commit || (commit->object.flags & TMP_MARK))
+               return;
+       commit->object.flags |= TMP_MARK;
+       ALLOC_GROW(tips->tip, tips->nr + 1, tips->alloc);
+       tips->tip[tips->nr++] = commit;
+}
+
+static void add_missing_tags(struct ref *src, struct ref **dst, struct ref ***dst_tail)
+{
+       struct string_list dst_tag = STRING_LIST_INIT_NODUP;
+       struct string_list src_tag = STRING_LIST_INIT_NODUP;
+       struct string_list_item *item;
+       struct ref *ref;
+       struct tips sent_tips;
+
+       /*
+        * Collect everything we know they would have at the end of
+        * this push, and collect all tags they have.
+        */
+       memset(&sent_tips, 0, sizeof(sent_tips));
+       for (ref = *dst; ref; ref = ref->next) {
+               if (ref->peer_ref &&
+                   !is_null_sha1(ref->peer_ref->new_sha1))
+                       add_to_tips(&sent_tips, ref->peer_ref->new_sha1);
+               else
+                       add_to_tips(&sent_tips, ref->old_sha1);
+               if (!prefixcmp(ref->name, "refs/tags/"))
+                       string_list_append(&dst_tag, ref->name);
+       }
+       clear_commit_marks_many(sent_tips.nr, sent_tips.tip, TMP_MARK);
+
+       sort_string_list(&dst_tag);
+
+       /* Collect tags they do not have. */
+       for (ref = src; ref; ref = ref->next) {
+               if (prefixcmp(ref->name, "refs/tags/"))
+                       continue; /* not a tag */
+               if (string_list_has_string(&dst_tag, ref->name))
+                       continue; /* they already have it */
+               if (sha1_object_info(ref->new_sha1, NULL) != OBJ_TAG)
+                       continue; /* be conservative */
+               item = string_list_append(&src_tag, ref->name);
+               item->util = ref;
+       }
+       string_list_clear(&dst_tag, 0);
+
+       /*
+        * At this point, src_tag lists tags that are missing from
+        * dst, and sent_tips lists the tips we are pushing or those
+        * that we know they already have. An element in the src_tag
+        * that is an ancestor of any of the sent_tips needs to be
+        * sent to the other side.
+        */
+       if (sent_tips.nr) {
+               for_each_string_list_item(item, &src_tag) {
+                       struct ref *ref = item->util;
+                       struct ref *dst_ref;
+                       struct commit *commit;
+
+                       if (is_null_sha1(ref->new_sha1))
+                               continue;
+                       commit = lookup_commit_reference_gently(ref->new_sha1, 1);
+                       if (!commit)
+                               /* not pushing a commit, which is not an error */
+                               continue;
+
+                       /*
+                        * Is this tag, which they do not have, reachable from
+                        * any of the commits we are sending?
+                        */
+                       if (!in_merge_bases_many(commit, sent_tips.nr, sent_tips.tip))
+                               continue;
+
+                       /* Add it in */
+                       dst_ref = make_linked_ref(ref->name, dst_tail);
+                       hashcpy(dst_ref->new_sha1, ref->new_sha1);
+                       dst_ref->peer_ref = copy_ref(ref);
+               }
+       }
+       string_list_clear(&src_tag, 0);
+       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
@@ -1227,9 +1342,6 @@ int match_push_refs(struct ref *src, struct ref **dst,
                const struct refspec *pat = NULL;
                char *dst_name;
 
-               if (ref->peer_ref)
-                       continue;
-
                dst_name = get_ref_match(rs, nr_refspec, ref, send_mirror, FROM_SRC, &pat);
                if (!dst_name)
                        continue;
@@ -1257,6 +1369,10 @@ int match_push_refs(struct ref *src, struct ref **dst,
        free_name:
                free(dst_name);
        }
+
+       if (flags & MATCH_REFS_FOLLOW_TAGS)
+               add_missing_tags(src, dst, &dst_tail);
+
        if (send_prune) {
                /* check for missing refs on the remote */
                for (ref = *dst; ref; ref = ref->next) {
@@ -1280,12 +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);
@@ -1300,6 +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:
@@ -1317,24 +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;
        }
 }
 
@@ -1351,8 +1490,7 @@ struct branch *branch_get(const char *name)
                ret->remote = remote_get(ret->remote_name);
                if (ret->merge_nr) {
                        int i;
-                       ret->merge = xcalloc(sizeof(*ret->merge),
-                                            ret->merge_nr);
+                       ret->merge = xcalloc(ret->merge_nr, sizeof(*ret->merge));
                        for (i = 0; i < ret->merge_nr; i++) {
                                ret->merge[i] = xcalloc(1, sizeof(**ret->merge));
                                ret->merge[i]->src = xstrdup(ret->merge_name[i]);
@@ -1466,7 +1604,12 @@ int get_fetch_map(const struct ref *remote_refs,
        } else {
                const char *name = refspec->src[0] ? refspec->src : "HEAD";
 
-               ref_map = get_remote_ref(remote_refs, name);
+               if (refspec->exact_sha1) {
+                       ref_map = alloc_ref(name);
+                       get_sha1_hex(name, ref_map->old_sha1);
+               } else {
+                       ref_map = get_remote_ref(remote_refs, name);
+               }
                if (!missing_ok && !ref_map)
                        die("Couldn't find remote ref %s", name);
                if (ref_map) {
@@ -1801,3 +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);
+}