Unify whitespace checking
[gitweb.git] / remote.c
index b032e81ac811e974ad6ff7fcd644922086499021..3fb0f99b29e7ffd927abf166cfa004c1937aaf60 100644 (file)
--- a/remote.c
+++ b/remote.c
@@ -5,6 +5,12 @@
 static struct remote **remotes;
 static int allocated_remotes;
 
+static struct branch **branches;
+static int allocated_branches;
+
+static struct branch *current_branch;
+static const char *default_remote_name;
+
 #define BUF_SIZE (2048)
 static char buffer[BUF_SIZE];
 
@@ -17,13 +23,22 @@ static void add_push_refspec(struct remote *remote, const char *ref)
        remote->push_refspec_nr = nr;
 }
 
-static void add_uri(struct remote *remote, const char *uri)
+static void add_fetch_refspec(struct remote *remote, const char *ref)
 {
-       int nr = remote->uri_nr + 1;
-       remote->uri =
-               xrealloc(remote->uri, nr * sizeof(char *));
-       remote->uri[nr-1] = uri;
-       remote->uri_nr = nr;
+       int nr = remote->fetch_refspec_nr + 1;
+       remote->fetch_refspec =
+               xrealloc(remote->fetch_refspec, nr * sizeof(char *));
+       remote->fetch_refspec[nr-1] = ref;
+       remote->fetch_refspec_nr = nr;
+}
+
+static void add_url(struct remote *remote, const char *url)
+{
+       int nr = remote->url_nr + 1;
+       remote->url =
+               xrealloc(remote->url, nr * sizeof(char *));
+       remote->url[nr-1] = url;
+       remote->url_nr = nr;
 }
 
 static struct remote *make_remote(const char *name, int len)
@@ -58,6 +73,54 @@ static struct remote *make_remote(const char *name, int len)
        return remotes[empty];
 }
 
+static void add_merge(struct branch *branch, const char *name)
+{
+       int nr = branch->merge_nr + 1;
+       branch->merge_name =
+               xrealloc(branch->merge_name, nr * sizeof(char *));
+       branch->merge_name[nr-1] = name;
+       branch->merge_nr = nr;
+}
+
+static struct branch *make_branch(const char *name, int len)
+{
+       int i, empty = -1;
+       char *refname;
+
+       for (i = 0; i < allocated_branches; i++) {
+               if (!branches[i]) {
+                       if (empty < 0)
+                               empty = i;
+               } else {
+                       if (len ? (!strncmp(name, branches[i]->name, len) &&
+                                  !branches[i]->name[len]) :
+                           !strcmp(name, branches[i]->name))
+                               return branches[i];
+               }
+       }
+
+       if (empty < 0) {
+               empty = allocated_branches;
+               allocated_branches += allocated_branches ? allocated_branches : 1;
+               branches = xrealloc(branches,
+                                  sizeof(*branches) * allocated_branches);
+               memset(branches + empty, 0,
+                      (allocated_branches - empty) * sizeof(*branches));
+       }
+       branches[empty] = xcalloc(1, sizeof(struct branch));
+       if (len)
+               branches[empty]->name = xstrndup(name, len);
+       else
+               branches[empty]->name = xstrdup(name);
+       refname = malloc(strlen(name) + strlen("refs/heads/") + 1);
+       strcpy(refname, "refs/heads/");
+       strcpy(refname + strlen("refs/heads/"),
+              branches[empty]->name);
+       branches[empty]->refname = refname;
+
+       return branches[empty];
+}
+
 static void read_remotes_file(struct remote *remote)
 {
        FILE *f = fopen(git_path("remotes/%s", remote->name), "r");
@@ -74,6 +137,9 @@ static void read_remotes_file(struct remote *remote)
                } else if (!prefixcmp(buffer, "Push:")) {
                        value_list = 1;
                        s = buffer + 5;
+               } else if (!prefixcmp(buffer, "Pull:")) {
+                       value_list = 2;
+                       s = buffer + 5;
                } else
                        continue;
 
@@ -88,11 +154,14 @@ static void read_remotes_file(struct remote *remote)
 
                switch (value_list) {
                case 0:
-                       add_uri(remote, xstrdup(s));
+                       add_url(remote, xstrdup(s));
                        break;
                case 1:
                        add_push_refspec(remote, xstrdup(s));
                        break;
+               case 2:
+                       add_fetch_refspec(remote, xstrdup(s));
+                       break;
                }
        }
        fclose(f);
@@ -101,6 +170,8 @@ static void read_remotes_file(struct remote *remote)
 static void read_branches_file(struct remote *remote)
 {
        const char *slash = strchr(remote->name, '/');
+       char *frag;
+       char *branch;
        int n = slash ? slash - remote->name : 1000;
        FILE *f = fopen(git_path("branches/%.*s", n, remote->name), "r");
        char *s, *p;
@@ -126,23 +197,41 @@ static void read_branches_file(struct remote *remote)
        strcpy(p, s);
        if (slash)
                strcat(p, slash);
-       add_uri(remote, p);
+       frag = strchr(p, '#');
+       if (frag) {
+               *(frag++) = '\0';
+               branch = xmalloc(strlen(frag) + 12);
+               strcpy(branch, "refs/heads/");
+               strcat(branch, frag);
+       } else {
+               branch = "refs/heads/master";
+       }
+       add_url(remote, p);
+       add_fetch_refspec(remote, branch);
+       remote->fetch_tags = 1; /* always auto-follow */
 }
 
-static char *default_remote_name = NULL;
-static const char *current_branch = NULL;
-static int current_branch_len = 0;
-
 static int handle_config(const char *key, const char *value)
 {
        const char *name;
        const char *subkey;
        struct remote *remote;
-       if (!prefixcmp(key, "branch.") && current_branch &&
-           !strncmp(key + 7, current_branch, current_branch_len) &&
-           !strcmp(key + 7 + current_branch_len, ".remote")) {
-               free(default_remote_name);
-               default_remote_name = xstrdup(value);
+       struct branch *branch;
+       if (!prefixcmp(key, "branch.")) {
+               name = key + 7;
+               subkey = strrchr(name, '.');
+               branch = make_branch(name, subkey - name);
+               if (!subkey)
+                       return 0;
+               if (!value)
+                       return 0;
+               if (!strcmp(subkey, ".remote")) {
+                       branch->remote_name = xstrdup(value);
+                       if (branch == current_branch)
+                               default_remote_name = branch->remote_name;
+               } else if (!strcmp(subkey, ".merge"))
+                       add_merge(branch, xstrdup(value));
+               return 0;
        }
        if (prefixcmp(key,  "remote."))
                return 0;
@@ -171,14 +260,26 @@ static int handle_config(const char *key, const char *value)
                return 0; /* ignore unknown booleans */
        }
        if (!strcmp(subkey, ".url")) {
-               add_uri(remote, xstrdup(value));
+               add_url(remote, xstrdup(value));
        } else if (!strcmp(subkey, ".push")) {
                add_push_refspec(remote, xstrdup(value));
+       } else if (!strcmp(subkey, ".fetch")) {
+               add_fetch_refspec(remote, xstrdup(value));
        } else if (!strcmp(subkey, ".receivepack")) {
                if (!remote->receivepack)
                        remote->receivepack = xstrdup(value);
                else
                        error("more than one receivepack given, using the first");
+       } else if (!strcmp(subkey, ".uploadpack")) {
+               if (!remote->uploadpack)
+                       remote->uploadpack = xstrdup(value);
+               else
+                       error("more than one uploadpack given, using the first");
+       } else if (!strcmp(subkey, ".tagopt")) {
+               if (!strcmp(value, "--no-tags"))
+                       remote->fetch_tags = -1;
+       } else if (!strcmp(subkey, ".proxy")) {
+               remote->http_proxy = xstrdup(value);
        }
        return 0;
 }
@@ -195,12 +296,50 @@ static void read_config(void)
        head_ref = resolve_ref("HEAD", sha1, 0, &flag);
        if (head_ref && (flag & REF_ISSYMREF) &&
            !prefixcmp(head_ref, "refs/heads/")) {
-               current_branch = head_ref + strlen("refs/heads/");
-               current_branch_len = strlen(current_branch);
+               current_branch =
+                       make_branch(head_ref + strlen("refs/heads/"), 0);
        }
        git_config(handle_config);
 }
 
+struct refspec *parse_ref_spec(int nr_refspec, const char **refspec)
+{
+       int i;
+       struct refspec *rs = xcalloc(sizeof(*rs), nr_refspec);
+       for (i = 0; i < nr_refspec; i++) {
+               const char *sp, *ep, *gp;
+               sp = refspec[i];
+               if (*sp == '+') {
+                       rs[i].force = 1;
+                       sp++;
+               }
+               gp = strchr(sp, '*');
+               ep = strchr(sp, ':');
+               if (gp && ep && gp > ep)
+                       gp = NULL;
+               if (ep) {
+                       if (ep[1]) {
+                               const char *glob = strchr(ep + 1, '*');
+                               if (!glob)
+                                       gp = NULL;
+                               if (gp)
+                                       rs[i].dst = xstrndup(ep + 1,
+                                                            glob - ep - 1);
+                               else
+                                       rs[i].dst = xstrdup(ep + 1);
+                       }
+               } else {
+                       ep = sp + strlen(sp);
+               }
+               if (gp) {
+                       rs[i].pattern = 1;
+                       ep = gp;
+               }
+               rs[i].src = xstrndup(sp, ep - sp);
+       }
+       return rs;
+}
+
 struct remote *remote_get(const char *name)
 {
        struct remote *ret;
@@ -210,14 +349,563 @@ struct remote *remote_get(const char *name)
                name = default_remote_name;
        ret = make_remote(name, 0);
        if (name[0] != '/') {
-               if (!ret->uri)
+               if (!ret->url)
                        read_remotes_file(ret);
-               if (!ret->uri)
+               if (!ret->url)
                        read_branches_file(ret);
        }
-       if (!ret->uri)
-               add_uri(ret, name);
-       if (!ret->uri)
+       if (!ret->url)
+               add_url(ret, name);
+       if (!ret->url)
+               return NULL;
+       ret->fetch = parse_ref_spec(ret->fetch_refspec_nr, ret->fetch_refspec);
+       ret->push = parse_ref_spec(ret->push_refspec_nr, ret->push_refspec);
+       return ret;
+}
+
+int for_each_remote(each_remote_fn fn, void *priv)
+{
+       int i, result = 0;
+       read_config();
+       for (i = 0; i < allocated_remotes && !result; i++) {
+               struct remote *r = remotes[i];
+               if (!r)
+                       continue;
+               if (!r->fetch)
+                       r->fetch = parse_ref_spec(r->fetch_refspec_nr,
+                                       r->fetch_refspec);
+               if (!r->push)
+                       r->push = parse_ref_spec(r->push_refspec_nr,
+                                       r->push_refspec);
+               result = fn(r, priv);
+       }
+       return result;
+}
+
+void ref_remove_duplicates(struct ref *ref_map)
+{
+       struct ref **posn;
+       struct ref *next;
+       for (; ref_map; ref_map = 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;
+                       }
+               }
+       }
+}
+
+int remote_has_url(struct remote *remote, const char *url)
+{
+       int i;
+       for (i = 0; i < remote->url_nr; i++) {
+               if (!strcmp(remote->url[i], url))
+                       return 1;
+       }
+       return 0;
+}
+
+int remote_find_tracking(struct remote *remote, struct refspec *refspec)
+{
+       int find_src = refspec->src == NULL;
+       char *needle, **result;
+       int i;
+
+       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;
+       }
+
+       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)
+                       continue;
+               if (fetch->pattern) {
+                       if (!prefixcmp(needle, key)) {
+                               *result = xmalloc(strlen(value) +
+                                                 strlen(needle) -
+                                                 strlen(key) + 1);
+                               strcpy(*result, value);
+                               strcpy(*result + strlen(value),
+                                      needle + strlen(key));
+                               refspec->force = fetch->force;
+                               return 0;
+                       }
+               } else if (!strcmp(needle, key)) {
+                       *result = xstrdup(value);
+                       refspec->force = fetch->force;
+                       return 0;
+               }
+       }
+       return -1;
+}
+
+struct ref *alloc_ref(unsigned namelen)
+{
+       struct ref *ret = xmalloc(sizeof(struct ref) + namelen);
+       memset(ret, 0, sizeof(struct ref) + namelen);
+       return ret;
+}
+
+static struct ref *copy_ref(const struct ref *ref)
+{
+       struct ref *ret = xmalloc(sizeof(struct ref) + strlen(ref->name) + 1);
+       memcpy(ret, ref, sizeof(struct ref) + strlen(ref->name) + 1);
+       ret->next = NULL;
+       return ret;
+}
+
+struct ref *copy_ref_list(const struct ref *ref)
+{
+       struct ref *ret = NULL;
+       struct ref **tail = &ret;
+       while (ref) {
+               *tail = copy_ref(ref);
+               ref = ref->next;
+               tail = &((*tail)->next);
+       }
+       return ret;
+}
+
+void free_refs(struct ref *ref)
+{
+       struct ref *next;
+       while (ref) {
+               next = ref->next;
+               if (ref->peer_ref)
+                       free(ref->peer_ref);
+               free(ref);
+               ref = next;
+       }
+}
+
+static int count_refspec_match(const char *pattern,
+                              struct ref *refs,
+                              struct ref **matched_ref)
+{
+       int patlen = strlen(pattern);
+       struct ref *matched_weak = NULL;
+       struct ref *matched = NULL;
+       int weak_match = 0;
+       int match = 0;
+
+       for (weak_match = match = 0; refs; refs = refs->next) {
+               char *name = refs->name;
+               int namelen = strlen(name);
+
+               if (!refname_match(pattern, name, ref_rev_parse_rules))
+                       continue;
+
+               /* A match is "weak" if it is with refs outside
+                * heads or tags, and did not specify the pattern
+                * in full (e.g. "refs/remotes/origin/master") or at
+                * least from the toplevel (e.g. "remotes/origin/master");
+                * otherwise "git push $URL master" would result in
+                * ambiguity between remotes/origin/master and heads/master
+                * at the remote site.
+                */
+               if (namelen != patlen &&
+                   patlen != namelen - 5 &&
+                   prefixcmp(name, "refs/heads/") &&
+                   prefixcmp(name, "refs/tags/")) {
+                       /* We want to catch the case where only weak
+                        * matches are found and there are multiple
+                        * matches, and where more than one strong
+                        * matches are found, as ambiguous.  One
+                        * strong match with zero or more weak matches
+                        * are acceptable as a unique match.
+                        */
+                       matched_weak = refs;
+                       weak_match++;
+               }
+               else {
+                       matched = refs;
+                       match++;
+               }
+       }
+       if (!matched) {
+               *matched_ref = matched_weak;
+               return weak_match;
+       }
+       else {
+               *matched_ref = matched;
+               return match;
+       }
+}
+
+static void tail_link_ref(struct ref *ref, struct ref ***tail)
+{
+       **tail = ref;
+       while (ref->next)
+               ref = ref->next;
+       *tail = &ref->next;
+}
+
+static struct ref *try_explicit_object_name(const char *name)
+{
+       unsigned char sha1[20];
+       struct ref *ref;
+       int len;
+
+       if (!*name) {
+               ref = alloc_ref(20);
+               strcpy(ref->name, "(delete)");
+               hashclr(ref->new_sha1);
+               return ref;
+       }
+       if (get_sha1(name, sha1))
                return NULL;
+       len = strlen(name) + 1;
+       ref = alloc_ref(len);
+       memcpy(ref->name, name, len);
+       hashcpy(ref->new_sha1, sha1);
+       return ref;
+}
+
+static struct ref *make_linked_ref(const char *name, struct ref ***tail)
+{
+       struct ref *ret;
+       size_t len;
+
+       len = strlen(name) + 1;
+       ret = alloc_ref(len);
+       memcpy(ret->name, name, len);
+       tail_link_ref(ret, tail);
        return ret;
 }
+
+static int match_explicit(struct ref *src, struct ref *dst,
+                         struct ref ***dst_tail,
+                         struct refspec *rs,
+                         int errs)
+{
+       struct ref *matched_src, *matched_dst;
+
+       const char *dst_value = rs->dst;
+
+       if (rs->pattern)
+               return errs;
+
+       matched_src = matched_dst = NULL;
+       switch (count_refspec_match(rs->src, src, &matched_src)) {
+       case 1:
+               break;
+       case 0:
+               /* The source could be in the get_sha1() format
+                * not a reference name.  :refs/other is a
+                * way to delete 'other' ref at the remote end.
+                */
+               matched_src = try_explicit_object_name(rs->src);
+               if (!matched_src)
+                       error("src refspec %s does not match any.", rs->src);
+               break;
+       default:
+               matched_src = NULL;
+               error("src refspec %s matches more than one.", rs->src);
+               break;
+       }
+
+       if (!matched_src)
+               errs = 1;
+
+       if (!dst_value) {
+               if (!matched_src)
+                       return errs;
+               dst_value = matched_src->name;
+       }
+
+       switch (count_refspec_match(dst_value, dst, &matched_dst)) {
+       case 1:
+               break;
+       case 0:
+               if (!memcmp(dst_value, "refs/", 5))
+                       matched_dst = make_linked_ref(dst_value, dst_tail);
+               else
+                       error("dst refspec %s does not match any "
+                             "existing ref on the remote and does "
+                             "not start with refs/.", dst_value);
+               break;
+       default:
+               matched_dst = NULL;
+               error("dst refspec %s matches more than one.",
+                     dst_value);
+               break;
+       }
+       if (errs || !matched_dst)
+               return 1;
+       if (matched_dst->peer_ref) {
+               errs = 1;
+               error("dst ref %s receives from more than one src.",
+                     matched_dst->name);
+       }
+       else {
+               matched_dst->peer_ref = matched_src;
+               matched_dst->force = rs->force;
+       }
+       return errs;
+}
+
+static int match_explicit_refs(struct ref *src, struct ref *dst,
+                              struct ref ***dst_tail, struct refspec *rs,
+                              int rs_nr)
+{
+       int i, errs;
+       for (i = errs = 0; i < rs_nr; i++)
+               errs |= match_explicit(src, dst, dst_tail, &rs[i], errs);
+       return -errs;
+}
+
+static const struct refspec *check_pattern_match(const struct refspec *rs,
+                                                int rs_nr,
+                                                const struct ref *src)
+{
+       int i;
+       for (i = 0; i < rs_nr; i++) {
+               if (rs[i].pattern && !prefixcmp(src->name, rs[i].src))
+                       return rs + i;
+       }
+       return NULL;
+}
+
+/*
+ * 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.
+ */
+int match_refs(struct ref *src, struct ref *dst, struct ref ***dst_tail,
+              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;
+
+       /* pick the remainder */
+       for ( ; src; src = src->next) {
+               struct ref *dst_peer;
+               const struct refspec *pat = NULL;
+               char *dst_name;
+               if (src->peer_ref)
+                       continue;
+               if (nr_refspec) {
+                       pat = check_pattern_match(rs, nr_refspec, src);
+                       if (!pat)
+                               continue;
+               }
+               else if (!send_mirror && prefixcmp(src->name, "refs/heads/"))
+                       /*
+                        * "matching refs"; traditionally we pushed everything
+                        * including refs outside refs/heads/ hierarchy, but
+                        * that does not make much sense these days.
+                        */
+                       continue;
+
+               if (pat) {
+                       const char *dst_side = pat->dst ? pat->dst : pat->src;
+                       dst_name = xmalloc(strlen(dst_side) +
+                                          strlen(src->name) -
+                                          strlen(pat->src) + 2);
+                       strcpy(dst_name, dst_side);
+                       strcat(dst_name, src->name + strlen(pat->src));
+               } else
+                       dst_name = xstrdup(src->name);
+               dst_peer = find_ref_by_name(dst, dst_name);
+               if (dst_peer && dst_peer->peer_ref)
+                       /* We're already sending something to this ref. */
+                       goto free_name;
+
+               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 nor --mirror.
+                        */
+                       goto free_name;
+               if (!dst_peer) {
+                       /* Create a new one and link it */
+                       dst_peer = make_linked_ref(dst_name, dst_tail);
+                       hashcpy(dst_peer->new_sha1, src->new_sha1);
+               }
+               dst_peer->peer_ref = src;
+               if (pat)
+                       dst_peer->force = pat->force;
+       free_name:
+               free(dst_name);
+       }
+       return 0;
+}
+
+struct branch *branch_get(const char *name)
+{
+       struct branch *ret;
+
+       read_config();
+       if (!name || !*name || !strcmp(name, "HEAD"))
+               ret = current_branch;
+       else
+               ret = make_branch(name, 0);
+       if (ret && ret->remote_name) {
+               ret->remote = remote_get(ret->remote_name);
+               if (ret->merge_nr) {
+                       int i;
+                       ret->merge = xcalloc(sizeof(*ret->merge),
+                                            ret->merge_nr);
+                       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]);
+                               remote_find_tracking(ret->remote,
+                                                    ret->merge[i]);
+                       }
+               }
+       }
+       return ret;
+}
+
+int branch_has_merge_config(struct branch *branch)
+{
+       return branch && !!branch->merge;
+}
+
+int branch_merge_matches(struct branch *branch,
+                                int i,
+                                const char *refname)
+{
+       if (!branch || i < 0 || i >= branch->merge_nr)
+               return 0;
+       return refname_match(branch->merge[i]->src, refname, ref_fetch_rules);
+}
+
+static struct ref *get_expanded_map(const struct ref *remote_refs,
+                                   const struct refspec *refspec)
+{
+       const struct ref *ref;
+       struct ref *ret = NULL;
+       struct ref **tail = &ret;
+
+       int remote_prefix_len = strlen(refspec->src);
+       int local_prefix_len = strlen(refspec->dst);
+
+       for (ref = remote_refs; ref; ref = ref->next) {
+               if (strchr(ref->name, '^'))
+                       continue; /* a dereference item */
+               if (!prefixcmp(ref->name, refspec->src)) {
+                       const char *match;
+                       struct ref *cpy = copy_ref(ref);
+                       match = ref->name + remote_prefix_len;
+
+                       cpy->peer_ref = alloc_ref(local_prefix_len +
+                                                 strlen(match) + 1);
+                       sprintf(cpy->peer_ref->name, "%s%s",
+                               refspec->dst, match);
+                       if (refspec->force)
+                               cpy->peer_ref->force = 1;
+                       *tail = cpy;
+                       tail = &cpy->next;
+               }
+       }
+
+       return ret;
+}
+
+static const struct ref *find_ref_by_name_abbrev(const struct ref *refs, const char *name)
+{
+       const struct ref *ref;
+       for (ref = refs; ref; ref = ref->next) {
+               if (refname_match(name, ref->name, ref_fetch_rules))
+                       return ref;
+       }
+       return NULL;
+}
+
+struct ref *get_remote_ref(const struct ref *remote_refs, const char *name)
+{
+       const struct ref *ref = find_ref_by_name_abbrev(remote_refs, name);
+
+       if (!ref)
+               return NULL;
+
+       return copy_ref(ref);
+}
+
+static struct ref *get_local_ref(const char *name)
+{
+       struct ref *ret;
+       if (!name)
+               return NULL;
+
+       if (!prefixcmp(name, "refs/")) {
+               ret = alloc_ref(strlen(name) + 1);
+               strcpy(ret->name, name);
+               return ret;
+       }
+
+       if (!prefixcmp(name, "heads/") ||
+           !prefixcmp(name, "tags/") ||
+           !prefixcmp(name, "remotes/")) {
+               ret = alloc_ref(strlen(name) + 6);
+               sprintf(ret->name, "refs/%s", name);
+               return ret;
+       }
+
+       ret = alloc_ref(strlen(name) + 12);
+       sprintf(ret->name, "refs/heads/%s", name);
+       return ret;
+}
+
+int get_fetch_map(const struct ref *remote_refs,
+                 const struct refspec *refspec,
+                 struct ref ***tail,
+                 int missing_ok)
+{
+       struct ref *ref_map, *rm;
+
+       if (refspec->pattern) {
+               ref_map = get_expanded_map(remote_refs, refspec);
+       } else {
+               const char *name = refspec->src[0] ? refspec->src : "HEAD";
+
+               ref_map = get_remote_ref(remote_refs, name);
+               if (!missing_ok && !ref_map)
+                       die("Couldn't find remote ref %s", name);
+               if (ref_map) {
+                       ref_map->peer_ref = get_local_ref(refspec->dst);
+                       if (ref_map->peer_ref && refspec->force)
+                               ref_map->peer_ref->force = 1;
+               }
+       }
+
+       for (rm = ref_map; rm; rm = rm->next) {
+               if (rm->peer_ref && check_ref_format(rm->peer_ref->name + 5))
+                       die("* refusing to create funny ref '%s' locally",
+                           rm->peer_ref->name);
+       }
+
+       if (ref_map)
+               tail_link_ref(ref_map, tail);
+
+       return 0;
+}