Merge branch 'lp/maint-diff-three-dash-with-graph'
[gitweb.git] / builtin / clone.c
index 0fb5956b48a77767e650d85f0818790736a4f94d..bbd5c96237fc332e159face6c8678d8ae3b9a3e9 100644 (file)
@@ -37,7 +37,7 @@ static const char * const builtin_clone_usage[] = {
        NULL
 };
 
-static int option_no_checkout, option_bare, option_mirror;
+static int option_no_checkout, option_bare, option_mirror, option_single_branch = -1;
 static int option_local, option_no_hardlinks, option_shared, option_recursive;
 static char *option_template, *option_depth;
 static char *option_origin = NULL;
@@ -92,6 +92,8 @@ static struct option builtin_clone_options[] = {
                   "path to git-upload-pack on the remote"),
        OPT_STRING(0, "depth", &option_depth, "depth",
                    "create a shallow clone of that depth"),
+       OPT_BOOL(0, "single-branch", &option_single_branch,
+                   "clone only one branch, HEAD or --branch"),
        OPT_STRING(0, "separate-git-dir", &real_git_dir, "gitdir",
                   "separate git dir from working tree"),
        OPT_STRING_LIST('c', "config", &option_config, "key=value",
@@ -230,9 +232,6 @@ static int add_one_reference(struct string_list_item *item, void *cb_data)
 {
        char *ref_git;
        struct strbuf alternate = STRBUF_INIT;
-       struct remote *remote;
-       struct transport *transport;
-       const struct ref *extra;
 
        /* Beware: real_path() and mkpath() return static buffer */
        ref_git = xstrdup(real_path(item->string));
@@ -247,14 +246,6 @@ static int add_one_reference(struct string_list_item *item, void *cb_data)
        strbuf_addf(&alternate, "%s/objects", ref_git);
        add_to_alternates_file(alternate.buf);
        strbuf_release(&alternate);
-
-       remote = remote_get(ref_git);
-       transport = transport_get(remote, ref_git);
-       for (extra = transport_get_remote_refs(transport); extra;
-            extra = extra->next)
-               add_extra_ref(extra->name, extra->old_sha1, 0);
-
-       transport_disconnect(transport);
        free(ref_git);
        return 0;
 }
@@ -361,13 +352,8 @@ static void copy_or_link_directory(struct strbuf *src, struct strbuf *dest,
        closedir(dir);
 }
 
-static const struct ref *clone_local(const char *src_repo,
-                                    const char *dest_repo)
+static void clone_local(const char *src_repo, const char *dest_repo)
 {
-       const struct ref *ret;
-       struct remote *remote;
-       struct transport *transport;
-
        if (option_shared) {
                struct strbuf alt = STRBUF_INIT;
                strbuf_addf(&alt, "%s/objects", src_repo);
@@ -383,13 +369,8 @@ static const struct ref *clone_local(const char *src_repo,
                strbuf_release(&dest);
        }
 
-       remote = remote_get(src_repo);
-       transport = transport_get(remote, src_repo);
-       ret = transport_get_remote_refs(transport);
-       transport_disconnect(transport);
        if (0 <= option_verbosity)
                printf(_("done.\n"));
-       return ret;
 }
 
 static const char *junk_work_tree;
@@ -420,6 +401,26 @@ static void remove_junk_on_signal(int signo)
        raise(signo);
 }
 
+static struct ref *find_remote_branch(const struct ref *refs, const char *branch)
+{
+       struct ref *ref;
+       struct strbuf head = STRBUF_INIT;
+       strbuf_addstr(&head, "refs/heads/");
+       strbuf_addstr(&head, branch);
+       ref = find_ref_by_name(refs, head.buf);
+       strbuf_release(&head);
+
+       if (ref)
+               return ref;
+
+       strbuf_addstr(&head, "refs/tags/");
+       strbuf_addstr(&head, branch);
+       ref = find_ref_by_name(refs, head.buf);
+       strbuf_release(&head);
+
+       return ref;
+}
+
 static struct ref *wanted_peer_refs(const struct ref *refs,
                struct refspec *refspec)
 {
@@ -427,8 +428,27 @@ static struct ref *wanted_peer_refs(const struct ref *refs,
        struct ref *local_refs = head;
        struct ref **tail = head ? &head->next : &local_refs;
 
-       get_fetch_map(refs, refspec, &tail, 0);
-       if (!option_mirror)
+       if (option_single_branch) {
+               struct ref *remote_head = NULL;
+
+               if (!option_branch)
+                       remote_head = guess_remote_head(head, refs, 0);
+               else
+                       remote_head = find_remote_branch(refs, option_branch);
+
+               if (!remote_head && option_branch)
+                       warning(_("Could not find remote branch %s to clone."),
+                               option_branch);
+               else {
+                       get_fetch_map(remote_head, refspec, &tail, 0);
+
+                       /* if --branch=tag, pull the requested tag explicitly */
+                       get_fetch_map(remote_head, tag_refspec, &tail, 0);
+               }
+       } else
+               get_fetch_map(refs, refspec, &tail, 0);
+
+       if (!option_mirror && !option_single_branch)
                get_fetch_map(refs, tag_refspec, &tail, 0);
 
        return local_refs;
@@ -441,11 +461,134 @@ static void write_remote_refs(const struct ref *local_refs)
        for (r = local_refs; r; r = r->next) {
                if (!r->peer_ref)
                        continue;
-               add_extra_ref(r->peer_ref->name, r->old_sha1, 0);
+               add_packed_ref(r->peer_ref->name, r->old_sha1);
        }
 
        pack_refs(PACK_REFS_ALL);
-       clear_extra_refs();
+}
+
+static void write_followtags(const struct ref *refs, const char *msg)
+{
+       const struct ref *ref;
+       for (ref = refs; ref; ref = ref->next) {
+               if (prefixcmp(ref->name, "refs/tags/"))
+                       continue;
+               if (!suffixcmp(ref->name, "^{}"))
+                       continue;
+               if (!has_sha1_file(ref->old_sha1))
+                       continue;
+               update_ref(msg, ref->name, ref->old_sha1,
+                          NULL, 0, DIE_ON_ERR);
+       }
+}
+
+static void update_remote_refs(const struct ref *refs,
+                              const struct ref *mapped_refs,
+                              const struct ref *remote_head_points_at,
+                              const char *branch_top,
+                              const char *msg)
+{
+       if (refs) {
+               write_remote_refs(mapped_refs);
+               if (option_single_branch)
+                       write_followtags(refs, msg);
+       }
+
+       if (remote_head_points_at && !option_bare) {
+               struct strbuf head_ref = STRBUF_INIT;
+               strbuf_addstr(&head_ref, branch_top);
+               strbuf_addstr(&head_ref, "HEAD");
+               create_symref(head_ref.buf,
+                             remote_head_points_at->peer_ref->name,
+                             msg);
+       }
+}
+
+static void update_head(const struct ref *our, const struct ref *remote,
+                       const char *msg)
+{
+       if (our && !prefixcmp(our->name, "refs/heads/")) {
+               /* Local default branch link */
+               create_symref("HEAD", our->name, NULL);
+               if (!option_bare) {
+                       const char *head = skip_prefix(our->name, "refs/heads/");
+                       update_ref(msg, "HEAD", our->old_sha1, NULL, 0, DIE_ON_ERR);
+                       install_branch_config(0, head, option_origin, our->name);
+               }
+       } else if (our) {
+               struct commit *c = lookup_commit_reference(our->old_sha1);
+               /* --branch specifies a non-branch (i.e. tags), detach HEAD */
+               update_ref(msg, "HEAD", c->object.sha1,
+                          NULL, REF_NODEREF, DIE_ON_ERR);
+       } else if (remote) {
+               /*
+                * We know remote HEAD points to a non-branch, or
+                * HEAD points to a branch but we don't know which one.
+                * Detach HEAD in all these cases.
+                */
+               update_ref(msg, "HEAD", remote->old_sha1,
+                          NULL, REF_NODEREF, DIE_ON_ERR);
+       }
+}
+
+static int checkout(void)
+{
+       unsigned char sha1[20];
+       char *head;
+       struct lock_file *lock_file;
+       struct unpack_trees_options opts;
+       struct tree *tree;
+       struct tree_desc t;
+       int err = 0, fd;
+
+       if (option_no_checkout)
+               return 0;
+
+       head = resolve_refdup("HEAD", sha1, 1, NULL);
+       if (!head) {
+               warning(_("remote HEAD refers to nonexistent ref, "
+                         "unable to checkout.\n"));
+               return 0;
+       }
+       if (!strcmp(head, "HEAD")) {
+               if (advice_detached_head)
+                       detach_advice(sha1_to_hex(sha1));
+       } else {
+               if (prefixcmp(head, "refs/heads/"))
+                       die(_("HEAD not found below refs/heads!"));
+       }
+       free(head);
+
+       /* We need to be in the new work tree for the checkout */
+       setup_work_tree();
+
+       lock_file = xcalloc(1, sizeof(struct lock_file));
+       fd = hold_locked_index(lock_file, 1);
+
+       memset(&opts, 0, sizeof opts);
+       opts.update = 1;
+       opts.merge = 1;
+       opts.fn = oneway_merge;
+       opts.verbose_update = (option_verbosity > 0);
+       opts.src_index = &the_index;
+       opts.dst_index = &the_index;
+
+       tree = parse_tree_indirect(sha1);
+       parse_tree(tree);
+       init_tree_desc(&t, tree->buffer, tree->size);
+       unpack_trees(1, &t, &opts);
+
+       if (write_cache(fd, active_cache, active_nr) ||
+           commit_locked_index(lock_file))
+               die(_("unable to write new index file"));
+
+       err |= run_hook(NULL, "post-checkout", sha1_to_hex(null_sha1),
+                       sha1_to_hex(sha1), "1", NULL);
+
+       if (!err && option_recursive)
+               err = run_command_v_opt(argv_submodule, RUN_GIT_CMD);
+
+       return err;
 }
 
 static int write_one_config(const char *key, const char *value, void *data)
@@ -475,11 +618,13 @@ int cmd_clone(int argc, const char **argv, const char *prefix)
        const struct ref *remote_head_points_at;
        const struct ref *our_head_points_at;
        struct ref *mapped_refs;
+       const struct ref *ref;
        struct strbuf key = STRBUF_INIT, value = STRBUF_INIT;
        struct strbuf branch_top = STRBUF_INIT, reflog_msg = STRBUF_INIT;
        struct transport *transport = NULL;
-       char *src_ref_prefix = "refs/heads/";
-       int err = 0;
+       const char *src_ref_prefix = "refs/heads/";
+       struct remote *remote;
+       int err = 0, complete_refs_before_fetch = 1;
 
        struct refspec *refspec;
        const char *fetch_pattern;
@@ -498,6 +643,9 @@ int cmd_clone(int argc, const char **argv, const char *prefix)
                usage_msg_opt(_("You must specify a repository to clone."),
                        builtin_clone_usage, builtin_clone_options);
 
+       if (option_single_branch == -1)
+               option_single_branch = option_depth ? 1 : 0;
+
        if (option_mirror)
                option_bare = 1;
 
@@ -630,13 +778,10 @@ int cmd_clone(int argc, const char **argv, const char *prefix)
 
        strbuf_reset(&value);
 
-       if (is_local) {
-               refs = clone_local(path, git_dir);
-               mapped_refs = wanted_peer_refs(refs, refspec);
-       } else {
-               struct remote *remote = remote_get(option_origin);
-               transport = transport_get(remote, remote->url[0]);
+       remote = remote_get(option_origin);
+       transport = transport_get(remote, remote->url[0]);
 
+       if (!is_local) {
                if (!transport->get_refs_list || !transport->fetch)
                        die(_("Don't know how to clone %s"), transport->url);
 
@@ -645,49 +790,57 @@ int cmd_clone(int argc, const char **argv, const char *prefix)
                if (option_depth)
                        transport_set_option(transport, TRANS_OPT_DEPTH,
                                             option_depth);
+               if (option_single_branch)
+                       transport_set_option(transport, TRANS_OPT_FOLLOWTAGS, "1");
 
                transport_set_verbosity(transport, option_verbosity, option_progress);
 
                if (option_upload_pack)
                        transport_set_option(transport, TRANS_OPT_UPLOADPACK,
                                             option_upload_pack);
-
-               refs = transport_get_remote_refs(transport);
-               if (refs) {
-                       mapped_refs = wanted_peer_refs(refs, refspec);
-                       transport_fetch_refs(transport, mapped_refs);
-               }
        }
 
+       refs = transport_get_remote_refs(transport);
+
        if (refs) {
-               clear_extra_refs();
+               mapped_refs = wanted_peer_refs(refs, refspec);
+               /*
+                * transport_get_remote_refs() may return refs with null sha-1
+                * in mapped_refs (see struct transport->get_refs_list
+                * comment). In that case we need fetch it early because
+                * remote_head code below relies on it.
+                *
+                * for normal clones, transport_get_remote_refs() should
+                * return reliable ref set, we can delay cloning until after
+                * remote HEAD check.
+                */
+               for (ref = refs; ref; ref = ref->next)
+                       if (is_null_sha1(ref->old_sha1)) {
+                               complete_refs_before_fetch = 0;
+                               break;
+                       }
 
-               write_remote_refs(mapped_refs);
+               if (!is_local && !complete_refs_before_fetch)
+                       transport_fetch_refs(transport, mapped_refs);
 
                remote_head = find_ref_by_name(refs, "HEAD");
                remote_head_points_at =
                        guess_remote_head(remote_head, mapped_refs, 0);
 
                if (option_branch) {
-                       struct strbuf head = STRBUF_INIT;
-                       strbuf_addstr(&head, src_ref_prefix);
-                       strbuf_addstr(&head, option_branch);
                        our_head_points_at =
-                               find_ref_by_name(mapped_refs, head.buf);
-                       strbuf_release(&head);
-
-                       if (!our_head_points_at) {
-                               warning(_("Remote branch %s not found in "
-                                       "upstream %s, using HEAD instead"),
-                                       option_branch, option_origin);
-                               our_head_points_at = remote_head_points_at;
-                       }
+                               find_remote_branch(mapped_refs, option_branch);
+
+                       if (!our_head_points_at)
+                               die(_("Remote branch %s not found in upstream %s"),
+                                   option_branch, option_origin);
                }
                else
                        our_head_points_at = remote_head_points_at;
        }
        else {
                warning(_("You appear to have cloned an empty repository."));
+               mapped_refs = NULL;
                our_head_points_at = NULL;
                remote_head_points_at = NULL;
                remote_head = NULL;
@@ -697,84 +850,20 @@ int cmd_clone(int argc, const char **argv, const char *prefix)
                                              "refs/heads/master");
        }
 
-       if (remote_head_points_at && !option_bare) {
-               struct strbuf head_ref = STRBUF_INIT;
-               strbuf_addstr(&head_ref, branch_top.buf);
-               strbuf_addstr(&head_ref, "HEAD");
-               create_symref(head_ref.buf,
-                             remote_head_points_at->peer_ref->name,
-                             reflog_msg.buf);
-       }
+       if (is_local)
+               clone_local(path, git_dir);
+       else if (refs && complete_refs_before_fetch)
+               transport_fetch_refs(transport, mapped_refs);
 
-       if (our_head_points_at) {
-               /* Local default branch link */
-               create_symref("HEAD", our_head_points_at->name, NULL);
-               if (!option_bare) {
-                       const char *head = skip_prefix(our_head_points_at->name,
-                                                      "refs/heads/");
-                       update_ref(reflog_msg.buf, "HEAD",
-                                  our_head_points_at->old_sha1,
-                                  NULL, 0, DIE_ON_ERR);
-                       install_branch_config(0, head, option_origin,
-                                             our_head_points_at->name);
-               }
-       } else if (remote_head) {
-               /* Source had detached HEAD pointing somewhere. */
-               if (!option_bare) {
-                       update_ref(reflog_msg.buf, "HEAD",
-                                  remote_head->old_sha1,
-                                  NULL, REF_NODEREF, DIE_ON_ERR);
-                       our_head_points_at = remote_head;
-               }
-       } else {
-               /* Nothing to checkout out */
-               if (!option_no_checkout)
-                       warning(_("remote HEAD refers to nonexistent ref, "
-                               "unable to checkout.\n"));
-               option_no_checkout = 1;
-       }
+       update_remote_refs(refs, mapped_refs, remote_head_points_at,
+                          branch_top.buf, reflog_msg.buf);
 
-       if (transport) {
-               transport_unlock_pack(transport);
-               transport_disconnect(transport);
-       }
+       update_head(our_head_points_at, remote_head, reflog_msg.buf);
 
-       if (!option_no_checkout) {
-               struct lock_file *lock_file = xcalloc(1, sizeof(struct lock_file));
-               struct unpack_trees_options opts;
-               struct tree *tree;
-               struct tree_desc t;
-               int fd;
-
-               /* We need to be in the new work tree for the checkout */
-               setup_work_tree();
-
-               fd = hold_locked_index(lock_file, 1);
-
-               memset(&opts, 0, sizeof opts);
-               opts.update = 1;
-               opts.merge = 1;
-               opts.fn = oneway_merge;
-               opts.verbose_update = (option_verbosity > 0);
-               opts.src_index = &the_index;
-               opts.dst_index = &the_index;
-
-               tree = parse_tree_indirect(our_head_points_at->old_sha1);
-               parse_tree(tree);
-               init_tree_desc(&t, tree->buffer, tree->size);
-               unpack_trees(1, &t, &opts);
-
-               if (write_cache(fd, active_cache, active_nr) ||
-                   commit_locked_index(lock_file))
-                       die(_("unable to write new index file"));
-
-               err |= run_hook(NULL, "post-checkout", sha1_to_hex(null_sha1),
-                               sha1_to_hex(our_head_points_at->old_sha1), "1",
-                               NULL);
-
-               if (!err && option_recursive)
-                       err = run_command_v_opt(argv_submodule, RUN_GIT_CMD);
-       }
+       transport_unlock_pack(transport);
+       transport_disconnect(transport);
+
+       err = checkout();
 
        strbuf_release(&reflog_msg);
        strbuf_release(&branch_top);