Merge branch 'tr/userdiff-c-returns-pointer' into maint
[gitweb.git] / remote.c
index d66e2f3c93dc72a7112ce101278ae937cc914320..e2ef99114478c49863809ea5cef46392a5a8c0e9 100644 (file)
--- a/remote.c
+++ b/remote.c
@@ -6,6 +6,7 @@
 #include "revision.h"
 #include "dir.h"
 #include "tag.h"
+#include "string-list.h"
 
 static struct refspec s_tag_refspec = {
        0,
@@ -28,6 +29,11 @@ struct rewrite {
        int instead_of_nr;
        int instead_of_alloc;
 };
+struct rewrites {
+       struct rewrite **rewrite;
+       int rewrite_alloc;
+       int rewrite_nr;
+};
 
 static struct remote **remotes;
 static int remotes_alloc;
@@ -41,14 +47,18 @@ static struct branch *current_branch;
 static const char *default_remote_name;
 static int explicit_default_remote_name;
 
-static struct rewrite **rewrite;
-static int rewrite_alloc;
-static int rewrite_nr;
+static struct rewrites rewrites;
+static struct rewrites rewrites_push;
 
 #define BUF_SIZE (2048)
 static char buffer[BUF_SIZE];
 
-static const char *alias_url(const char *url)
+static int valid_remote(const struct remote *remote)
+{
+       return (!!remote->url) || (!!remote->foreign_vcs);
+}
+
+static const char *alias_url(const char *url, struct rewrites *r)
 {
        int i, j;
        char *ret;
@@ -57,14 +67,14 @@ static const char *alias_url(const char *url)
 
        longest = NULL;
        longest_i = -1;
-       for (i = 0; i < rewrite_nr; i++) {
-               if (!rewrite[i])
+       for (i = 0; i < r->rewrite_nr; i++) {
+               if (!r->rewrite[i])
                        continue;
-               for (j = 0; j < rewrite[i]->instead_of_nr; j++) {
-                       if (!prefixcmp(url, rewrite[i]->instead_of[j].s) &&
+               for (j = 0; j < r->rewrite[i]->instead_of_nr; j++) {
+                       if (!prefixcmp(url, r->rewrite[i]->instead_of[j].s) &&
                            (!longest ||
-                            longest->len < rewrite[i]->instead_of[j].len)) {
-                               longest = &(rewrite[i]->instead_of[j]);
+                            longest->len < r->rewrite[i]->instead_of[j].len)) {
+                               longest = &(r->rewrite[i]->instead_of[j]);
                                longest_i = i;
                        }
                }
@@ -72,10 +82,10 @@ static const char *alias_url(const char *url)
        if (!longest)
                return url;
 
-       ret = xmalloc(rewrite[longest_i]->baselen +
+       ret = xmalloc(r->rewrite[longest_i]->baselen +
                     (strlen(url) - longest->len) + 1);
-       strcpy(ret, rewrite[longest_i]->base);
-       strcpy(ret + rewrite[longest_i]->baselen, url + longest->len);
+       strcpy(ret, r->rewrite[longest_i]->base);
+       strcpy(ret + r->rewrite[longest_i]->baselen, url + longest->len);
        return ret;
 }
 
@@ -101,9 +111,23 @@ static void add_url(struct remote *remote, const char *url)
        remote->url[remote->url_nr++] = url;
 }
 
+static void add_pushurl(struct remote *remote, const char *pushurl)
+{
+       ALLOC_GROW(remote->pushurl, remote->pushurl_nr + 1, remote->pushurl_alloc);
+       remote->pushurl[remote->pushurl_nr++] = pushurl;
+}
+
+static void add_pushurl_alias(struct remote *remote, const char *url)
+{
+       const char *pushurl = alias_url(url, &rewrites_push);
+       if (pushurl != url)
+               add_pushurl(remote, pushurl);
+}
+
 static void add_url_alias(struct remote *remote, const char *url)
 {
-       add_url(remote, alias_url(url));
+       add_url(remote, alias_url(url, &rewrites));
+       add_pushurl_alias(remote, url);
 }
 
 static struct remote *make_remote(const char *name, int len)
@@ -163,22 +187,22 @@ static struct branch *make_branch(const char *name, int len)
        return ret;
 }
 
-static struct rewrite *make_rewrite(const char *base, int len)
+static struct rewrite *make_rewrite(struct rewrites *r, const char *base, int len)
 {
        struct rewrite *ret;
        int i;
 
-       for (i = 0; i < rewrite_nr; i++) {
+       for (i = 0; i < r->rewrite_nr; i++) {
                if (len
-                   ? (len == rewrite[i]->baselen &&
-                      !strncmp(base, rewrite[i]->base, len))
-                   : !strcmp(base, rewrite[i]->base))
-                       return rewrite[i];
+                   ? (len == r->rewrite[i]->baselen &&
+                      !strncmp(base, r->rewrite[i]->base, len))
+                   : !strcmp(base, r->rewrite[i]->base))
+                       return r->rewrite[i];
        }
 
-       ALLOC_GROW(rewrite, rewrite_nr + 1, rewrite_alloc);
+       ALLOC_GROW(r->rewrite, r->rewrite_nr + 1, r->rewrite_alloc);
        ret = xcalloc(1, sizeof(struct rewrite));
-       rewrite[rewrite_nr++] = ret;
+       r->rewrite[r->rewrite_nr++] = ret;
        if (len) {
                ret->base = xstrndup(base, len);
                ret->baselen = len;
@@ -301,7 +325,7 @@ static void read_branches_file(struct remote *remote)
                strbuf_addstr(&branch, "HEAD:");
        }
        add_url_alias(remote, p);
-       add_fetch_refspec(remote, strbuf_detach(&branch, 0));
+       add_fetch_refspec(remote, strbuf_detach(&branch, NULL));
        /*
         * Cogito compatible push: push current HEAD to remote #branch
         * (master if missing)
@@ -312,7 +336,7 @@ static void read_branches_file(struct remote *remote)
                strbuf_addf(&branch, ":refs/heads/%s", frag);
        else
                strbuf_addstr(&branch, ":refs/heads/master");
-       add_push_refspec(remote, strbuf_detach(&branch, 0));
+       add_push_refspec(remote, strbuf_detach(&branch, NULL));
        remote->fetch_tags = 1; /* always auto-follow */
 }
 
@@ -349,8 +373,13 @@ static int handle_config(const char *key, const char *value, void *cb)
                subkey = strrchr(name, '.');
                if (!subkey)
                        return 0;
-               rewrite = make_rewrite(name, subkey - name);
                if (!strcmp(subkey, ".insteadof")) {
+                       rewrite = make_rewrite(&rewrites, name, subkey - name);
+                       if (!value)
+                               return config_error_nonbool(key);
+                       add_instead_of(rewrite, xstrdup(value));
+               } else if (!strcmp(subkey, ".pushinsteadof")) {
+                       rewrite = make_rewrite(&rewrites_push, name, subkey - name);
                        if (!value)
                                return config_error_nonbool(key);
                        add_instead_of(rewrite, xstrdup(value));
@@ -373,12 +402,18 @@ static int handle_config(const char *key, const char *value, void *cb)
                remote->mirror = git_config_bool(key, value);
        else if (!strcmp(subkey, ".skipdefaultupdate"))
                remote->skip_default_update = git_config_bool(key, value);
-
+       else if (!strcmp(subkey, ".skipfetchall"))
+               remote->skip_default_update = git_config_bool(key, value);
        else if (!strcmp(subkey, ".url")) {
                const char *v;
                if (git_config_string(&v, key, value))
                        return -1;
                add_url(remote, v);
+       } else if (!strcmp(subkey, ".pushurl")) {
+               const char *v;
+               if (git_config_string(&v, key, value))
+                       return -1;
+               add_pushurl(remote, v);
        } else if (!strcmp(subkey, ".push")) {
                const char *v;
                if (git_config_string(&v, key, value))
@@ -408,9 +443,13 @@ static int handle_config(const char *key, const char *value, void *cb)
        } else if (!strcmp(subkey, ".tagopt")) {
                if (!strcmp(value, "--no-tags"))
                        remote->fetch_tags = -1;
+               else if (!strcmp(value, "--tags"))
+                       remote->fetch_tags = 2;
        } else if (!strcmp(subkey, ".proxy")) {
                return git_config_string((const char **)&remote->http_proxy,
                                         key, value);
+       } else if (!strcmp(subkey, ".vcs")) {
+               return git_config_string(&remote->foreign_vcs, key, value);
        }
        return 0;
 }
@@ -419,10 +458,17 @@ static void alias_all_urls(void)
 {
        int i, j;
        for (i = 0; i < remotes_nr; i++) {
+               int add_pushurl_aliases;
                if (!remotes[i])
                        continue;
+               for (j = 0; j < remotes[i]->pushurl_nr; j++) {
+                       remotes[i]->pushurl[j] = alias_url(remotes[i]->pushurl[j], &rewrites);
+               }
+               add_pushurl_aliases = remotes[i]->pushurl_nr == 0;
                for (j = 0; j < remotes[i]->url_nr; j++) {
-                       remotes[i]->url[j] = alias_url(remotes[i]->url[j]);
+                       if (add_pushurl_aliases)
+                               add_pushurl_alias(remotes[i], remotes[i]->url[j]);
+                       remotes[i]->url[j] = alias_url(remotes[i]->url[j], &rewrites);
                }
        }
 }
@@ -432,7 +478,7 @@ static void read_config(void)
        unsigned char sha1[20];
        const char *head_ref;
        int flag;
-       if (default_remote_name) // did this already
+       if (default_remote_name) /* did this already */
                return;
        default_remote_name = xstrdup("origin");
        current_branch = NULL;
@@ -446,23 +492,6 @@ static void read_config(void)
        alias_all_urls();
 }
 
-/*
- * We need to make sure the tracking branches are well formed, but a
- * wildcard refspec in "struct refspec" must have a trailing slash. We
- * temporarily drop the trailing '/' while calling check_ref_format(),
- * and put it back.  The caller knows that a CHECK_REF_FORMAT_ONELEVEL
- * error return is Ok for a wildcard refspec.
- */
-static int verify_refname(char *name, int is_glob)
-{
-       int result;
-
-       result = check_ref_format(name);
-       if (is_glob && result == CHECK_REF_FORMAT_WILDCARD)
-               result = CHECK_REF_FORMAT_OK;
-       return result;
-}
-
 /*
  * This function frees a refspec array.
  * Warning: code paths should be checked to ensure that the src
@@ -486,13 +515,13 @@ static void free_refspecs(struct refspec *refspec, int nr_refspec)
 static struct refspec *parse_refspec_internal(int nr_refspec, const char **refspec, int fetch, int verify)
 {
        int i;
-       int st;
        struct refspec *rs = xcalloc(sizeof(*rs), nr_refspec);
 
        for (i = 0; i < nr_refspec; i++) {
                size_t llen;
                int is_glob;
                const char *lhs, *rhs;
+               int flags;
 
                is_glob = 0;
 
@@ -530,6 +559,7 @@ static struct refspec *parse_refspec_internal(int nr_refspec, const char **refsp
 
                rs[i].pattern = is_glob;
                rs[i].src = xstrndup(lhs, llen);
+               flags = REFNAME_ALLOW_ONELEVEL | (is_glob ? REFNAME_REFSPEC_PATTERN : 0);
 
                if (fetch) {
                        /*
@@ -539,26 +569,20 @@ static struct refspec *parse_refspec_internal(int nr_refspec, const char **refsp
                         */
                        if (!*rs[i].src)
                                ; /* empty is ok */
-                       else {
-                               st = verify_refname(rs[i].src, is_glob);
-                               if (st && st != CHECK_REF_FORMAT_ONELEVEL)
-                                       goto invalid;
-                       }
+                       else if (check_refname_format(rs[i].src, flags))
+                               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.
                         */
-                       if (!rs[i].dst) {
+                       if (!rs[i].dst)
                                ; /* ok */
-                       } else if (!*rs[i].dst) {
+                       else if (!*rs[i].dst)
                                ; /* ok */
-                       } else {
-                               st = verify_refname(rs[i].dst, is_glob);
-                               if (st && st != CHECK_REF_FORMAT_ONELEVEL)
-                                       goto invalid;
-                       }
+                       else if (check_refname_format(rs[i].dst, flags))
+                               goto invalid;
                } else {
                        /*
                         * LHS
@@ -570,8 +594,7 @@ static struct refspec *parse_refspec_internal(int nr_refspec, const char **refsp
                        if (!*rs[i].src)
                                ; /* empty is ok */
                        else if (is_glob) {
-                               st = verify_refname(rs[i].src, is_glob);
-                               if (st && st != CHECK_REF_FORMAT_ONELEVEL)
+                               if (check_refname_format(rs[i].src, flags))
                                        goto invalid;
                        }
                        else
@@ -584,14 +607,12 @@ static struct refspec *parse_refspec_internal(int nr_refspec, const char **refsp
                         * - otherwise it must be a valid looking ref.
                         */
                        if (!rs[i].dst) {
-                               st = verify_refname(rs[i].src, is_glob);
-                               if (st && st != CHECK_REF_FORMAT_ONELEVEL)
+                               if (check_refname_format(rs[i].src, flags))
                                        goto invalid;
                        } else if (!*rs[i].dst) {
                                goto invalid;
                        } else {
-                               st = verify_refname(rs[i].dst, is_glob);
-                               if (st && st != CHECK_REF_FORMAT_ONELEVEL)
+                               if (check_refname_format(rs[i].dst, flags))
                                        goto invalid;
                        }
                }
@@ -613,10 +634,9 @@ static struct refspec *parse_refspec_internal(int nr_refspec, const char **refsp
 
 int valid_fetch_refspec(const char *fetch_refspec_str)
 {
-       const char *fetch_refspec[] = { fetch_refspec_str };
        struct refspec *refspec;
 
-       refspec = parse_refspec_internal(1, fetch_refspec, 1, 1);
+       refspec = parse_refspec_internal(1, &fetch_refspec_str, 1, 1);
        free_refspecs(refspec, 1);
        return !!refspec;
 }
@@ -631,6 +651,16 @@ static struct refspec *parse_push_refspec(int nr_refspec, const char **refspec)
        return parse_refspec_internal(nr_refspec, refspec, 0, 0);
 }
 
+void free_refspec(int nr_refspec, struct refspec *refspec)
+{
+       int i;
+       for (i = 0; i < nr_refspec; i++) {
+               free(refspec[i].src);
+               free(refspec[i].dst);
+       }
+       free(refspec);
+}
+
 static int valid_remote_nick(const char *name)
 {
        if (!name[0] || is_dot_or_dotdot(name))
@@ -653,14 +683,14 @@ struct remote *remote_get(const char *name)
 
        ret = make_remote(name, 0);
        if (valid_remote_nick(name)) {
-               if (!ret->url)
+               if (!valid_remote(ret))
                        read_remotes_file(ret);
-               if (!ret->url)
+               if (!valid_remote(ret))
                        read_branches_file(ret);
        }
-       if (name_given && !ret->url)
+       if (name_given && !valid_remote(ret))
                add_url_alias(ret, name);
-       if (!ret->url)
+       if (!valid_remote(ret))
                return NULL;
        ret->fetch = parse_fetch_refspec(ret->fetch_refspec_nr, ret->fetch_refspec);
        ret->push = parse_push_refspec(ret->push_refspec_nr, ret->push_refspec);
@@ -699,29 +729,33 @@ int for_each_remote(each_remote_fn fn, void *priv)
 
 void ref_remove_duplicates(struct ref *ref_map)
 {
-       struct ref **posn;
-       struct ref *next;
-       for (; ref_map; ref_map = ref_map->next) {
+       struct string_list refs = STRING_LIST_INIT_NODUP;
+       struct string_list_item *item = NULL;
+       struct ref *prev = NULL, *next = NULL;
+       for (; ref_map; prev = ref_map, ref_map = next) {
+               next = ref_map->next;
                if (!ref_map->peer_ref)
                        continue;
-               posn = &ref_map->next;
-               while (*posn) {
-                       if ((*posn)->peer_ref &&
-                           !strcmp((*posn)->peer_ref->name,
-                                   ref_map->peer_ref->name)) {
-                               if (strcmp((*posn)->name, ref_map->name))
-                                       die("%s tracks both %s and %s",
-                                           ref_map->peer_ref->name,
-                                           (*posn)->name, ref_map->name);
-                               next = (*posn)->next;
-                               free((*posn)->peer_ref);
-                               free(*posn);
-                               *posn = next;
-                       } else {
-                               posn = &(*posn)->next;
-                       }
+
+               item = string_list_lookup(&refs, ref_map->peer_ref->name);
+               if (item) {
+                       if (strcmp(((struct ref *)item->util)->name,
+                                  ref_map->name))
+                               die("%s tracks both %s and %s",
+                                   ref_map->peer_ref->name,
+                                   ((struct ref *)item->util)->name,
+                                   ref_map->name);
+                       prev->next = ref_map->next;
+                       free(ref_map->peer_ref);
+                       free(ref_map);
+                       ref_map = prev; /* skip this; we freed it */
+                       continue;
                }
+
+               item = string_list_insert(&refs, ref_map->peer_ref->name);
+               item->util = ref_map;
        }
+       string_list_clear(&refs, 0);
 }
 
 int remote_has_url(struct remote *remote, const char *url)
@@ -769,42 +803,56 @@ static int match_name_with_pattern(const char *key, const char *name,
        return ret;
 }
 
-int remote_find_tracking(struct remote *remote, struct refspec *refspec)
+static int query_refspecs(struct refspec *refs, int ref_count, struct refspec *query)
 {
-       int find_src = refspec->src == NULL;
-       char *needle, **result;
        int i;
+       int find_src = !query->src;
 
-       if (find_src) {
-               if (!refspec->dst)
-                       return error("find_tracking: need either src or dst");
-               needle = refspec->dst;
-               result = &refspec->src;
-       } else {
-               needle = refspec->src;
-               result = &refspec->dst;
-       }
+       if (find_src && !query->dst)
+               return error("query_refspecs: need either src or dst");
 
-       for (i = 0; i < remote->fetch_refspec_nr; i++) {
-               struct refspec *fetch = &remote->fetch[i];
-               const char *key = find_src ? fetch->dst : fetch->src;
-               const char *value = find_src ? fetch->src : fetch->dst;
-               if (!fetch->dst)
+       for (i = 0; i < ref_count; i++) {
+               struct refspec *refspec = &refs[i];
+               const char *key = find_src ? refspec->dst : refspec->src;
+               const char *value = find_src ? refspec->src : refspec->dst;
+               const char *needle = find_src ? query->dst : query->src;
+               char **result = find_src ? &query->src : &query->dst;
+
+               if (!refspec->dst)
                        continue;
-               if (fetch->pattern) {
+               if (refspec->pattern) {
                        if (match_name_with_pattern(key, needle, value, result)) {
-                               refspec->force = fetch->force;
+                               query->force = refspec->force;
                                return 0;
                        }
                } else if (!strcmp(needle, key)) {
                        *result = xstrdup(value);
-                       refspec->force = fetch->force;
+                       query->force = refspec->force;
                        return 0;
                }
        }
        return -1;
 }
 
+char *apply_refspecs(struct refspec *refspecs, int nr_refspec,
+                    const char *name)
+{
+       struct refspec query;
+
+       memset(&query, 0, sizeof(struct refspec));
+       query.src = (char *)name;
+
+       if (query_refspecs(refspecs, nr_refspec, &query))
+               return NULL;
+
+       return query.dst;
+}
+
+int remote_find_tracking(struct remote *remote, struct refspec *refspec)
+{
+       return query_refspecs(remote->fetch, remote->fetch_refspec_nr, refspec);
+}
+
 static struct ref *alloc_ref_with_prefix(const char *prefix, size_t prefixlen,
                const char *name)
 {
@@ -820,7 +868,7 @@ struct ref *alloc_ref(const char *name)
        return alloc_ref_with_prefix("", 0, name);
 }
 
-static struct ref *copy_ref(const struct ref *ref)
+struct ref *copy_ref(const struct ref *ref)
 {
        struct ref *cpy;
        size_t len;
@@ -1024,7 +1072,7 @@ static int match_explicit(struct ref *src, struct ref *dst,
        case 0:
                if (!memcmp(dst_value, "refs/", 5))
                        matched_dst = make_linked_ref(dst_value, dst_tail);
-               else if((dst_guess = guess_ref(dst_value, matched_src)))
+               else if ((dst_guess = guess_ref(dst_value, matched_src)))
                        matched_dst = make_linked_ref(dst_guess, dst_tail);
                else
                        error("unable to push to unqualified destination: %s\n"
@@ -1085,26 +1133,38 @@ static const struct refspec *check_pattern_match(const struct refspec *rs,
                return NULL;
 }
 
+static struct ref **tail_ref(struct ref **head)
+{
+       struct ref **tail = head;
+       while (*tail)
+               tail = &((*tail)->next);
+       return tail;
+}
+
 /*
- * Note. This is used only by "push"; refspec matching rules for
- * push and fetch are subtly different, so do not try to reuse it
- * without thinking.
+ * Given the set of refs the local repository has, the set of refs the
+ * remote repository has, and the refspec used for push, determine
+ * what remote refs we will update and with what value by setting
+ * peer_ref (which object is being pushed) and force (if the push is
+ * forced) in elements of "dst". The function may add new elements to
+ * dst (e.g. pushing to a new branch, done in match_explicit_refs).
  */
-int match_refs(struct ref *src, struct ref *dst, struct ref ***dst_tail,
-              int nr_refspec, const char **refspec, int flags)
+int match_push_refs(struct ref *src, struct ref **dst,
+                   int nr_refspec, const char **refspec, int flags)
 {
        struct refspec *rs;
        int send_all = flags & MATCH_REFS_ALL;
        int send_mirror = flags & MATCH_REFS_MIRROR;
        int errs;
-       static const char *default_refspec[] = { ":", 0 };
+       static const char *default_refspec[] = { ":", NULL };
+       struct ref **dst_tail = tail_ref(dst);
 
        if (!nr_refspec) {
                nr_refspec = 1;
                refspec = default_refspec;
        }
        rs = parse_push_refspec(nr_refspec, (const char **) refspec);
-       errs = match_explicit_refs(src, dst, dst_tail, rs, nr_refspec);
+       errs = match_explicit_refs(src, *dst, &dst_tail, rs, nr_refspec);
 
        /* pick the remainder */
        for ( ; src; src = src->next) {
@@ -1134,7 +1194,7 @@ int match_refs(struct ref *src, struct ref *dst, struct ref ***dst_tail,
                                                     dst_side, &dst_name))
                                die("Didn't think it matches any more");
                }
-               dst_peer = find_ref_by_name(dst, dst_name);
+               dst_peer = find_ref_by_name(*dst, dst_name);
                if (dst_peer) {
                        if (dst_peer->peer_ref)
                                /* We're already sending something to this ref. */
@@ -1150,7 +1210,7 @@ int match_refs(struct ref *src, struct ref *dst, struct ref ***dst_tail,
                                goto free_name;
 
                        /* Create a new one and link it */
-                       dst_peer = make_linked_ref(dst_name, dst_tail);
+                       dst_peer = make_linked_ref(dst_name, &dst_tail);
                        hashcpy(dst_peer->new_sha1, src->new_sha1);
                }
                dst_peer->peer_ref = copy_ref(src);
@@ -1163,6 +1223,56 @@ int match_refs(struct ref *src, struct ref *dst, struct ref ***dst_tail,
        return 0;
 }
 
+void set_ref_status_for_push(struct ref *remote_refs, int send_mirror,
+       int force_update)
+{
+       struct ref *ref;
+
+       for (ref = remote_refs; ref; ref = ref->next) {
+               if (ref->peer_ref)
+                       hashcpy(ref->new_sha1, ref->peer_ref->new_sha1);
+               else if (!send_mirror)
+                       continue;
+
+               ref->deletion = is_null_sha1(ref->new_sha1);
+               if (!ref->deletion &&
+                       !hashcmp(ref->old_sha1, ref->new_sha1)) {
+                       ref->status = REF_STATUS_UPTODATE;
+                       continue;
+               }
+
+               /* This part determines what can overwrite what.
+                * The rules are:
+                *
+                * (0) you can always use --force or +A:B notation to
+                *     selectively force individual ref pairs.
+                *
+                * (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.
+                *
+                * (4) regardless of all of the above, removing :B is
+                *     always allowed.
+                */
+
+               ref->nonfastforward =
+                       !ref->deletion &&
+                       !is_null_sha1(ref->old_sha1) &&
+                       (!has_sha1_file(ref->old_sha1)
+                         || !ref_newer(ref->new_sha1, ref->old_sha1));
+
+               if (ref->nonfastforward && !ref->force && !force_update) {
+                       ref->status = REF_STATUS_REJECT_NONFASTFORWARD;
+                       continue;
+               }
+       }
+}
+
 struct branch *branch_get(const char *name)
 {
        struct branch *ret;
@@ -1254,7 +1364,7 @@ struct ref *get_remote_ref(const struct ref *remote_refs, const char *name)
 
 static struct ref *get_local_ref(const char *name)
 {
-       if (!name)
+       if (!name || name[0] == '\0')
                return NULL;
 
        if (!prefixcmp(name, "refs/"))
@@ -1292,8 +1402,8 @@ int get_fetch_map(const struct ref *remote_refs,
 
        for (rmp = &ref_map; *rmp; ) {
                if ((*rmp)->peer_ref) {
-                       int st = check_ref_format((*rmp)->peer_ref->name + 5);
-                       if (st && st != CHECK_REF_FORMAT_ONELEVEL) {
+                       if (check_refname_format((*rmp)->peer_ref->name + 5,
+                               REFNAME_ALLOW_ONELEVEL)) {
                                struct ref *ignore = *rmp;
                                error("* Ignoring funny ref '%s' locally",
                                      (*rmp)->peer_ref->name);
@@ -1399,13 +1509,13 @@ int stat_tracking_info(struct branch *branch, int *num_ours, int *num_theirs)
        base = branch->merge[0]->dst;
        if (!resolve_ref(base, sha1, 1, NULL))
                return 0;
-       theirs = lookup_commit(sha1);
+       theirs = lookup_commit_reference(sha1);
        if (!theirs)
                return 0;
 
        if (!resolve_ref(branch->refname, sha1, 1, NULL))
                return 0;
-       ours = lookup_commit(sha1);
+       ours = lookup_commit_reference(sha1);
        if (!ours)
                return 0;
 
@@ -1485,7 +1595,7 @@ static int one_local_ref(const char *refname, const unsigned char *sha1, int fla
        int len;
 
        /* we already know it starts with refs/ to get here */
-       if (check_ref_format(refname + 5))
+       if (check_refname_format(refname + 5, 0))
                return 0;
 
        len = strlen(refname) + 1;
@@ -1532,7 +1642,9 @@ struct ref *guess_remote_head(const struct ref *head,
 
        /* Look for another ref that points there */
        for (r = refs; r; r = r->next) {
-               if (r != head && !hashcmp(r->old_sha1, head->old_sha1)) {
+               if (r != head &&
+                   !prefixcmp(r->name, "refs/heads/") &&
+                   !hashcmp(r->old_sha1, head->old_sha1)) {
                        *tail = copy_ref(r);
                        tail = &((*tail)->next);
                        if (!all)
@@ -1542,3 +1654,53 @@ struct ref *guess_remote_head(const struct ref *head,
 
        return list;
 }
+
+struct stale_heads_info {
+       struct string_list *ref_names;
+       struct ref **stale_refs_tail;
+       struct refspec *refs;
+       int ref_count;
+};
+
+static int get_stale_heads_cb(const char *refname,
+       const unsigned char *sha1, int flags, void *cb_data)
+{
+       struct stale_heads_info *info = cb_data;
+       struct refspec query;
+       memset(&query, 0, sizeof(struct refspec));
+       query.dst = (char *)refname;
+
+       if (query_refspecs(info->refs, info->ref_count, &query))
+               return 0; /* No matches */
+
+       /*
+        * If we did find a suitable refspec and it's not a symref and
+        * it's not in the list of refs that currently exist in that
+        * remote we consider it to be stale.
+        */
+       if (!((flags & REF_ISSYMREF) ||
+             string_list_has_string(info->ref_names, query.src))) {
+               struct ref *ref = make_linked_ref(refname, &info->stale_refs_tail);
+               hashcpy(ref->new_sha1, sha1);
+       }
+
+       free(query.src);
+       return 0;
+}
+
+struct ref *get_stale_heads(struct refspec *refs, int ref_count, struct ref *fetch_map)
+{
+       struct ref *ref, *stale_refs = NULL;
+       struct string_list ref_names = STRING_LIST_INIT_NODUP;
+       struct stale_heads_info info;
+       info.ref_names = &ref_names;
+       info.stale_refs_tail = &stale_refs;
+       info.refs = refs;
+       info.ref_count = ref_count;
+       for (ref = fetch_map; ref; ref = ref->next)
+               string_list_append(&ref_names, ref->name);
+       sort_string_list(&ref_names);
+       for_each_ref(get_stale_heads_cb, &info);
+       string_list_clear(&ref_names, 0);
+       return stale_refs;
+}