commit: use generations in paint_down_to_common()
[gitweb.git] / builtin / checkout.c
index 899bd8db0b50d8d8a1cb00a9432692d9b898980d..4e803ae0921d78137ae69a04f910e420238fd420 100644 (file)
@@ -1,4 +1,6 @@
 #include "builtin.h"
+#include "config.h"
+#include "checkout.h"
 #include "lockfile.h"
 #include "parse-options.h"
 #include "refs.h"
@@ -52,14 +54,14 @@ struct checkout_opts {
        struct tree *source_tree;
 };
 
-static int post_checkout_hook(struct commit *old, struct commit *new,
+static int post_checkout_hook(struct commit *old_commit, struct commit *new_commit,
                              int changed)
 {
        return run_hook_le(NULL, "post-checkout",
-                          sha1_to_hex(old ? old->object.oid.hash : null_sha1),
-                          sha1_to_hex(new ? new->object.oid.hash : null_sha1),
+                          oid_to_hex(old_commit ? &old_commit->object.oid : &null_oid),
+                          oid_to_hex(new_commit ? &new_commit->object.oid : &null_oid),
                           changed ? "1" : "0", NULL);
-       /* "new" can be NULL when checking out from the index before
+       /* "new_commit" can be NULL when checking out from the index before
           a commit exists. */
 
 }
@@ -76,7 +78,7 @@ static int update_some(const unsigned char *sha1, struct strbuf *base,
 
        len = base->len + strlen(pathname);
        ce = xcalloc(1, cache_entry_size(len));
-       hashcpy(ce->sha1, sha1);
+       hashcpy(ce->oid.hash, sha1);
        memcpy(ce->name, base->buf, base->len);
        memcpy(ce->name + base->len, pathname, len - base->len);
        ce->ce_flags = create_ce_flags(0) | CE_UPDATE;
@@ -92,7 +94,7 @@ static int update_some(const unsigned char *sha1, struct strbuf *base,
        if (pos >= 0) {
                struct cache_entry *old = active_cache[pos];
                if (ce->ce_mode == old->ce_mode &&
-                   !hashcmp(ce->sha1, old->sha1)) {
+                   !oidcmp(&ce->oid, &old->oid)) {
                        old->ce_flags |= CE_UPDATE;
                        free(ce);
                        return 0;
@@ -175,9 +177,9 @@ static int checkout_merged(int pos, const struct checkout *state)
        const char *path = ce->name;
        mmfile_t ancestor, ours, theirs;
        int status;
-       unsigned char sha1[20];
+       struct object_id oid;
        mmbuffer_t result_buf;
-       unsigned char threeway[3][20];
+       struct object_id threeway[3];
        unsigned mode = 0;
 
        memset(threeway, 0, sizeof(threeway));
@@ -186,18 +188,18 @@ static int checkout_merged(int pos, const struct checkout *state)
                stage = ce_stage(ce);
                if (!stage || strcmp(path, ce->name))
                        break;
-               hashcpy(threeway[stage - 1], ce->sha1);
+               oidcpy(&threeway[stage - 1], &ce->oid);
                if (stage == 2)
                        mode = create_ce_mode(ce->ce_mode);
                pos++;
                ce = active_cache[pos];
        }
-       if (is_null_sha1(threeway[1]) || is_null_sha1(threeway[2]))
+       if (is_null_oid(&threeway[1]) || is_null_oid(&threeway[2]))
                return error(_("path '%s' does not have necessary versions"), path);
 
-       read_mmblob(&ancestor, threeway[0]);
-       read_mmblob(&ours, threeway[1]);
-       read_mmblob(&theirs, threeway[2]);
+       read_mmblob(&ancestor, &threeway[0]);
+       read_mmblob(&ours, &threeway[1]);
+       read_mmblob(&theirs, &threeway[2]);
 
        /*
         * NEEDSWORK: re-create conflicts from merges with
@@ -216,22 +218,23 @@ static int checkout_merged(int pos, const struct checkout *state)
        /*
         * NEEDSWORK:
         * There is absolutely no reason to write this as a blob object
-        * and create a phony cache entry just to leak.  This hack is
-        * primarily to get to the write_entry() machinery that massages
-        * the contents to work-tree format and writes out which only
-        * allows it for a cache entry.  The code in write_entry() needs
-        * to be refactored to allow us to feed a <buffer, size, mode>
-        * instead of a cache entry.  Such a refactoring would help
-        * merge_recursive as well (it also writes the merge result to the
-        * object database even when it may contain conflicts).
+        * and create a phony cache entry.  This hack is primarily to get
+        * to the write_entry() machinery that massages the contents to
+        * work-tree format and writes out which only allows it for a
+        * cache entry.  The code in write_entry() needs to be refactored
+        * to allow us to feed a <buffer, size, mode> instead of a cache
+        * entry.  Such a refactoring would help merge_recursive as well
+        * (it also writes the merge result to the object database even
+        * when it may contain conflicts).
         */
-       if (write_sha1_file(result_buf.ptr, result_buf.size,
-                           blob_type, sha1))
+       if (write_object_file(result_buf.ptr, result_buf.size, blob_type, &oid))
                die(_("Unable to add merge result for '%s'"), path);
-       ce = make_cache_entry(mode, sha1, path, 2, 0);
+       free(result_buf.ptr);
+       ce = make_cache_entry(mode, oid.hash, path, 2, 0);
        if (!ce)
                die(_("make_cache_entry failed for path '%s'"), path);
        status = checkout_entry(ce, state, NULL);
+       free(ce);
        return status;
 }
 
@@ -239,12 +242,12 @@ static int checkout_paths(const struct checkout_opts *opts,
                          const char *revision)
 {
        int pos;
-       struct checkout state;
+       struct checkout state = CHECKOUT_INIT;
        static char *ps_matched;
-       unsigned char rev[20];
+       struct object_id rev;
        struct commit *head;
        int errs = 0;
-       struct lock_file *lock_file;
+       struct lock_file lock_file = LOCK_INIT;
 
        if (opts->track != BRANCH_TRACK_UNSPECIFIED)
                die(_("'%s' cannot be used with updating paths"), "--track");
@@ -272,9 +275,7 @@ static int checkout_paths(const struct checkout_opts *opts,
                return run_add_interactive(revision, "--patch=checkout",
                                           &opts->pathspec);
 
-       lock_file = xcalloc(1, sizeof(struct lock_file));
-
-       hold_locked_index(lock_file, 1);
+       hold_locked_index(&lock_file, LOCK_DIE_ON_ERROR);
        if (read_cache_preload(&opts->pathspec) < 0)
                return error(_("index file corrupt"));
 
@@ -352,10 +353,11 @@ static int checkout_paths(const struct checkout_opts *opts,
                return 1;
 
        /* Now we are committed to check them out */
-       memset(&state, 0, sizeof(state));
        state.force = 1;
        state.refresh_cache = 1;
        state.istate = &the_index;
+
+       enable_delayed_checkout(&state);
        for (pos = 0; pos < active_nr; pos++) {
                struct cache_entry *ce = active_cache[pos];
                if (ce->ce_flags & CE_MATCHED) {
@@ -370,12 +372,13 @@ static int checkout_paths(const struct checkout_opts *opts,
                        pos = skip_same_name(ce, pos) - 1;
                }
        }
+       errs |= finish_delayed_checkout(&state);
 
-       if (write_locked_index(&the_index, lock_file, COMMIT_LOCK))
+       if (write_locked_index(&the_index, &lock_file, COMMIT_LOCK))
                die(_("unable to write new index file"));
 
-       read_ref_full("HEAD", 0, rev, NULL);
-       head = lookup_commit_reference_gently(rev, 1);
+       read_ref_full("HEAD", 0, &rev, NULL);
+       head = lookup_commit_reference_gently(&rev, 1);
 
        errs |= post_checkout_hook(head, head, 0);
        return errs;
@@ -397,10 +400,16 @@ static void show_local_changes(struct object *head,
 static void describe_detached_head(const char *msg, struct commit *commit)
 {
        struct strbuf sb = STRBUF_INIT;
+
        if (!parse_commit(commit))
                pp_commit_easy(CMIT_FMT_ONELINE, commit, &sb);
-       fprintf(stderr, "%s %s... %s\n", msg,
-               find_unique_abbrev(commit->object.oid.hash, DEFAULT_ABBREV), sb.buf);
+       if (print_sha1_ellipsis()) {
+               fprintf(stderr, "%s %s... %s\n", msg,
+                       find_unique_abbrev(commit->object.oid.hash, DEFAULT_ABBREV), sb.buf);
+       } else {
+               fprintf(stderr, "%s %s %s\n", msg,
+                       find_unique_abbrev(commit->object.oid.hash, DEFAULT_ABBREV), sb.buf);
+       }
        strbuf_release(&sb);
 }
 
@@ -431,6 +440,7 @@ static int reset_tree(struct tree *tree, const struct checkout_opts *o,
                 * update paths in the work tree, and we cannot revert
                 * them.
                 */
+               /* fallthrough */
        case 0:
                return 0;
        default:
@@ -453,7 +463,7 @@ static void setup_branch_path(struct branch_info *branch)
 {
        struct strbuf buf = STRBUF_INIT;
 
-       strbuf_branchname(&buf, branch->name);
+       strbuf_branchname(&buf, branch->name, INTERPRET_BRANCH_LOCAL);
        if (strcmp(buf.buf, branch->name))
                branch->name = xstrdup(buf.buf);
        strbuf_splice(&buf, 0, 0, "refs/heads/", 11);
@@ -461,20 +471,21 @@ static void setup_branch_path(struct branch_info *branch)
 }
 
 static int merge_working_tree(const struct checkout_opts *opts,
-                             struct branch_info *old,
-                             struct branch_info *new,
+                             struct branch_info *old_branch_info,
+                             struct branch_info *new_branch_info,
                              int *writeout_error)
 {
        int ret;
-       struct lock_file *lock_file = xcalloc(1, sizeof(struct lock_file));
+       struct lock_file lock_file = LOCK_INIT;
 
-       hold_locked_index(lock_file, 1);
+       hold_locked_index(&lock_file, LOCK_DIE_ON_ERROR);
        if (read_cache_preload(NULL) < 0)
                return error(_("index file corrupt"));
 
        resolve_undo_clear();
        if (opts->force) {
-               ret = reset_tree(new->commit->tree, opts, 1, writeout_error);
+               ret = reset_tree(get_commit_tree(new_branch_info->commit),
+                                opts, 1, writeout_error);
                if (ret)
                        return ret;
        } else {
@@ -500,7 +511,7 @@ static int merge_working_tree(const struct checkout_opts *opts,
                topts.initial_checkout = is_cache_unborn();
                topts.update = 1;
                topts.merge = 1;
-               topts.gently = opts->merge && old->commit;
+               topts.gently = opts->merge && old_branch_info->commit;
                topts.verbose_update = opts->show_progress;
                topts.fn = twoway_merge;
                if (opts->overwrite_ignore) {
@@ -508,11 +519,11 @@ static int merge_working_tree(const struct checkout_opts *opts,
                        topts.dir->flags |= DIR_SHOW_IGNORED;
                        setup_standard_excludes(topts.dir);
                }
-               tree = parse_tree_indirect(old->commit ?
-                                          old->commit->object.oid.hash :
-                                          EMPTY_TREE_SHA1_BIN);
+               tree = parse_tree_indirect(old_branch_info->commit ?
+                                          &old_branch_info->commit->object.oid :
+                                          the_hash_algo->empty_tree);
                init_tree_desc(&trees[0], tree->buffer, tree->size);
-               tree = parse_tree_indirect(new->commit->object.oid.hash);
+               tree = parse_tree_indirect(&new_branch_info->commit->object.oid);
                init_tree_desc(&trees[1], tree->buffer, tree->size);
 
                ret = unpack_trees(2, trees, &topts);
@@ -529,10 +540,10 @@ static int merge_working_tree(const struct checkout_opts *opts,
                                return 1;
 
                        /*
-                        * Without old->commit, the below is the same as
+                        * Without old_branch_info->commit, the below is the same as
                         * the two-tree unpack we already tried and failed.
                         */
-                       if (!old->commit)
+                       if (!old_branch_info->commit)
                                return 1;
 
                        /* Do more real merge */
@@ -560,18 +571,23 @@ static int merge_working_tree(const struct checkout_opts *opts,
                        o.verbosity = 0;
                        work = write_tree_from_memory(&o);
 
-                       ret = reset_tree(new->commit->tree, opts, 1,
+                       ret = reset_tree(get_commit_tree(new_branch_info->commit),
+                                        opts, 1,
                                         writeout_error);
                        if (ret)
                                return ret;
-                       o.ancestor = old->name;
-                       o.branch1 = new->name;
+                       o.ancestor = old_branch_info->name;
+                       o.branch1 = new_branch_info->name;
                        o.branch2 = "local";
-                       ret = merge_trees(&o, new->commit->tree, work,
-                               old->commit->tree, &result);
+                       ret = merge_trees(&o,
+                                         get_commit_tree(new_branch_info->commit),
+                                         work,
+                                         get_commit_tree(old_branch_info->commit),
+                                         &result);
                        if (ret < 0)
                                exit(128);
-                       ret = reset_tree(new->commit->tree, opts, 0,
+                       ret = reset_tree(get_commit_tree(new_branch_info->commit),
+                                        opts, 0,
                                         writeout_error);
                        strbuf_release(&o.obuf);
                        if (ret)
@@ -585,19 +601,19 @@ static int merge_working_tree(const struct checkout_opts *opts,
        if (!cache_tree_fully_valid(active_cache_tree))
                cache_tree_update(&the_index, WRITE_TREE_SILENT | WRITE_TREE_REPAIR);
 
-       if (write_locked_index(&the_index, lock_file, COMMIT_LOCK))
+       if (write_locked_index(&the_index, &lock_file, COMMIT_LOCK))
                die(_("unable to write new index file"));
 
        if (!opts->force && !opts->quiet)
-               show_local_changes(&new->commit->object, &opts->diff_options);
+               show_local_changes(&new_branch_info->commit->object, &opts->diff_options);
 
        return 0;
 }
 
-static void report_tracking(struct branch_info *new)
+static void report_tracking(struct branch_info *new_branch_info)
 {
        struct strbuf sb = STRBUF_INIT;
-       struct branch *branch = branch_get(new->name);
+       struct branch *branch = branch_get(new_branch_info->name);
 
        if (!format_tracking_info(branch, &sb))
                return;
@@ -606,101 +622,104 @@ static void report_tracking(struct branch_info *new)
 }
 
 static void update_refs_for_switch(const struct checkout_opts *opts,
-                                  struct branch_info *old,
-                                  struct branch_info *new)
+                                  struct branch_info *old_branch_info,
+                                  struct branch_info *new_branch_info)
 {
        struct strbuf msg = STRBUF_INIT;
        const char *old_desc, *reflog_msg;
        if (opts->new_branch) {
                if (opts->new_orphan_branch) {
-                       if (opts->new_branch_log && !log_all_ref_updates) {
+                       char *refname;
+
+                       refname = mkpathdup("refs/heads/%s", opts->new_orphan_branch);
+                       if (opts->new_branch_log &&
+                           !should_autocreate_reflog(refname)) {
                                int ret;
-                               char *refname;
                                struct strbuf err = STRBUF_INIT;
 
-                               refname = mkpathdup("refs/heads/%s", opts->new_orphan_branch);
                                ret = safe_create_reflog(refname, 1, &err);
-                               free(refname);
                                if (ret) {
                                        fprintf(stderr, _("Can not do reflog for '%s': %s\n"),
                                                opts->new_orphan_branch, err.buf);
                                        strbuf_release(&err);
+                                       free(refname);
                                        return;
                                }
                                strbuf_release(&err);
                        }
+                       free(refname);
                }
                else
-                       create_branch(opts->new_branch, new->name,
+                       create_branch(opts->new_branch, new_branch_info->name,
                                      opts->new_branch_force ? 1 : 0,
-                                     opts->new_branch_log,
                                      opts->new_branch_force ? 1 : 0,
+                                     opts->new_branch_log,
                                      opts->quiet,
                                      opts->track);
-               new->name = opts->new_branch;
-               setup_branch_path(new);
+               new_branch_info->name = opts->new_branch;
+               setup_branch_path(new_branch_info);
        }
 
-       old_desc = old->name;
-       if (!old_desc && old->commit)
-               old_desc = oid_to_hex(&old->commit->object.oid);
+       old_desc = old_branch_info->name;
+       if (!old_desc && old_branch_info->commit)
+               old_desc = oid_to_hex(&old_branch_info->commit->object.oid);
 
        reflog_msg = getenv("GIT_REFLOG_ACTION");
        if (!reflog_msg)
                strbuf_addf(&msg, "checkout: moving from %s to %s",
-                       old_desc ? old_desc : "(invalid)", new->name);
+                       old_desc ? old_desc : "(invalid)", new_branch_info->name);
        else
                strbuf_insert(&msg, 0, reflog_msg, strlen(reflog_msg));
 
-       if (!strcmp(new->name, "HEAD") && !new->path && !opts->force_detach) {
+       if (!strcmp(new_branch_info->name, "HEAD") && !new_branch_info->path && !opts->force_detach) {
                /* Nothing to do. */
-       } else if (opts->force_detach || !new->path) {  /* No longer on any branch. */
-               update_ref(msg.buf, "HEAD", new->commit->object.oid.hash, NULL,
-                          REF_NODEREF, UPDATE_REFS_DIE_ON_ERR);
+       } else if (opts->force_detach || !new_branch_info->path) {      /* No longer on any branch. */
+               update_ref(msg.buf, "HEAD", &new_branch_info->commit->object.oid, NULL,
+                          REF_NO_DEREF, UPDATE_REFS_DIE_ON_ERR);
                if (!opts->quiet) {
-                       if (old->path &&
+                       if (old_branch_info->path &&
                            advice_detached_head && !opts->force_detach)
-                               detach_advice(new->name);
-                       describe_detached_head(_("HEAD is now at"), new->commit);
+                               detach_advice(new_branch_info->name);
+                       describe_detached_head(_("HEAD is now at"), new_branch_info->commit);
                }
-       } else if (new->path) { /* Switch branches. */
-               if (create_symref("HEAD", new->path, msg.buf) < 0)
+       } else if (new_branch_info->path) {     /* Switch branches. */
+               if (create_symref("HEAD", new_branch_info->path, msg.buf) < 0)
                        die(_("unable to update HEAD"));
                if (!opts->quiet) {
-                       if (old->path && !strcmp(new->path, old->path)) {
+                       if (old_branch_info->path && !strcmp(new_branch_info->path, old_branch_info->path)) {
                                if (opts->new_branch_force)
                                        fprintf(stderr, _("Reset branch '%s'\n"),
-                                               new->name);
+                                               new_branch_info->name);
                                else
                                        fprintf(stderr, _("Already on '%s'\n"),
-                                               new->name);
+                                               new_branch_info->name);
                        } else if (opts->new_branch) {
                                if (opts->branch_exists)
-                                       fprintf(stderr, _("Switched to and reset branch '%s'\n"), new->name);
+                                       fprintf(stderr, _("Switched to and reset branch '%s'\n"), new_branch_info->name);
                                else
-                                       fprintf(stderr, _("Switched to a new branch '%s'\n"), new->name);
+                                       fprintf(stderr, _("Switched to a new branch '%s'\n"), new_branch_info->name);
                        } else {
                                fprintf(stderr, _("Switched to branch '%s'\n"),
-                                       new->name);
+                                       new_branch_info->name);
                        }
                }
-               if (old->path && old->name) {
-                       if (!ref_exists(old->path) && reflog_exists(old->path))
-                               delete_reflog(old->path);
+               if (old_branch_info->path && old_branch_info->name) {
+                       if (!ref_exists(old_branch_info->path) && reflog_exists(old_branch_info->path))
+                               delete_reflog(old_branch_info->path);
                }
        }
        remove_branch_state();
        strbuf_release(&msg);
        if (!opts->quiet &&
-           (new->path || (!opts->force_detach && !strcmp(new->name, "HEAD"))))
-               report_tracking(new);
+           (new_branch_info->path || (!opts->force_detach && !strcmp(new_branch_info->name, "HEAD"))))
+               report_tracking(new_branch_info);
 }
 
 static int add_pending_uninteresting_ref(const char *refname,
                                         const struct object_id *oid,
                                         int flags, void *cb_data)
 {
-       add_pending_sha1(cb_data, refname, oid->hash, UNINTERESTING);
+       add_pending_oid(cb_data, refname, oid, UNINTERESTING);
        return 0;
 }
 
@@ -773,11 +792,10 @@ static void suggest_reattach(struct commit *commit, struct rev_info *revs)
  * HEAD.  If it is not reachable from any ref, this is the last chance
  * for the user to do so without resorting to reflog.
  */
-static void orphaned_commit_warning(struct commit *old, struct commit *new)
+static void orphaned_commit_warning(struct commit *old_commit, struct commit *new_commit)
 {
        struct rev_info revs;
-       struct object *object = &old->object;
-       struct object_array refs;
+       struct object *object = &old_commit->object;
 
        init_revisions(&revs, NULL);
        setup_revisions(0, NULL, &revs, NULL);
@@ -786,59 +804,57 @@ static void orphaned_commit_warning(struct commit *old, struct commit *new)
        add_pending_object(&revs, object, oid_to_hex(&object->oid));
 
        for_each_ref(add_pending_uninteresting_ref, &revs);
-       add_pending_sha1(&revs, "HEAD", new->object.oid.hash, UNINTERESTING);
-
-       refs = revs.pending;
-       revs.leak_pending = 1;
+       add_pending_oid(&revs, "HEAD", &new_commit->object.oid, UNINTERESTING);
 
        if (prepare_revision_walk(&revs))
                die(_("internal error in revision walk"));
-       if (!(old->object.flags & UNINTERESTING))
-               suggest_reattach(old, &revs);
+       if (!(old_commit->object.flags & UNINTERESTING))
+               suggest_reattach(old_commit, &revs);
        else
-               describe_detached_head(_("Previous HEAD position was"), old);
+               describe_detached_head(_("Previous HEAD position was"), old_commit);
 
-       clear_commit_marks_for_object_array(&refs, ALL_REV_FLAGS);
-       free(refs.objects);
+       /* Clean up objects used, as they will be reused. */
+       clear_commit_marks_all(ALL_REV_FLAGS);
 }
 
 static int switch_branches(const struct checkout_opts *opts,
-                          struct branch_info *new)
+                          struct branch_info *new_branch_info)
 {
        int ret = 0;
-       struct branch_info old;
+       struct branch_info old_branch_info;
        void *path_to_free;
-       unsigned char rev[20];
+       struct object_id rev;
        int flag, writeout_error = 0;
-       memset(&old, 0, sizeof(old));
-       old.path = path_to_free = resolve_refdup("HEAD", 0, rev, &flag);
-       old.commit = lookup_commit_reference_gently(rev, 1);
+       memset(&old_branch_info, 0, sizeof(old_branch_info));
+       old_branch_info.path = path_to_free = resolve_refdup("HEAD", 0, &rev, &flag);
+       if (old_branch_info.path)
+               old_branch_info.commit = lookup_commit_reference_gently(&rev, 1);
        if (!(flag & REF_ISSYMREF))
-               old.path = NULL;
+               old_branch_info.path = NULL;
 
-       if (old.path)
-               skip_prefix(old.path, "refs/heads/", &old.name);
+       if (old_branch_info.path)
+               skip_prefix(old_branch_info.path, "refs/heads/", &old_branch_info.name);
 
-       if (!new->name) {
-               new->name = "HEAD";
-               new->commit = old.commit;
-               if (!new->commit)
+       if (!new_branch_info->name) {
+               new_branch_info->name = "HEAD";
+               new_branch_info->commit = old_branch_info.commit;
+               if (!new_branch_info->commit)
                        die(_("You are on a branch yet to be born"));
-               parse_commit_or_die(new->commit);
+               parse_commit_or_die(new_branch_info->commit);
        }
 
-       ret = merge_working_tree(opts, &old, new, &writeout_error);
+       ret = merge_working_tree(opts, &old_branch_info, new_branch_info, &writeout_error);
        if (ret) {
                free(path_to_free);
                return ret;
        }
 
-       if (!opts->quiet && !old.path && old.commit && new->commit != old.commit)
-               orphaned_commit_warning(old.commit, new->commit);
+       if (!opts->quiet && !old_branch_info.path && old_branch_info.commit && new_branch_info->commit != old_branch_info.commit)
+               orphaned_commit_warning(old_branch_info.commit, new_branch_info->commit);
 
-       update_refs_for_switch(opts, &old, new);
+       update_refs_for_switch(opts, &old_branch_info, new_branch_info);
 
-       ret = post_checkout_hook(old.commit, new->commit, 1);
+       ret = post_checkout_hook(old_branch_info.commit, new_branch_info->commit, 1);
        free(path_to_free);
        return ret || writeout_error;
 }
@@ -852,62 +868,21 @@ static int git_checkout_config(const char *var, const char *value, void *cb)
        }
 
        if (starts_with(var, "submodule."))
-               return parse_submodule_config_option(var, value);
+               return git_default_submodule_config(var, value, NULL);
 
        return git_xmerge_config(var, value, NULL);
 }
 
-struct tracking_name_data {
-       /* const */ char *src_ref;
-       char *dst_ref;
-       unsigned char *dst_sha1;
-       int unique;
-};
-
-static int check_tracking_name(struct remote *remote, void *cb_data)
-{
-       struct tracking_name_data *cb = cb_data;
-       struct refspec query;
-       memset(&query, 0, sizeof(struct refspec));
-       query.src = cb->src_ref;
-       if (remote_find_tracking(remote, &query) ||
-           get_sha1(query.dst, cb->dst_sha1)) {
-               free(query.dst);
-               return 0;
-       }
-       if (cb->dst_ref) {
-               free(query.dst);
-               cb->unique = 0;
-               return 0;
-       }
-       cb->dst_ref = query.dst;
-       return 0;
-}
-
-static const char *unique_tracking_name(const char *name, unsigned char *sha1)
-{
-       struct tracking_name_data cb_data = { NULL, NULL, NULL, 1 };
-       char src_ref[PATH_MAX];
-       snprintf(src_ref, PATH_MAX, "refs/heads/%s", name);
-       cb_data.src_ref = src_ref;
-       cb_data.dst_sha1 = sha1;
-       for_each_remote(check_tracking_name, &cb_data);
-       if (cb_data.unique)
-               return cb_data.dst_ref;
-       free(cb_data.dst_ref);
-       return NULL;
-}
-
 static int parse_branchname_arg(int argc, const char **argv,
                                int dwim_new_local_branch_ok,
-                               struct branch_info *new,
+                               struct branch_info *new_branch_info,
                                struct checkout_opts *opts,
-                               unsigned char rev[20])
+                               struct object_id *rev)
 {
        struct tree **source_tree = &opts->source_tree;
        const char **new_branch = &opts->new_branch;
        int argcount = 0;
-       unsigned char branch_rev[20];
+       struct object_id branch_rev;
        const char *arg;
        int dash_dash_pos;
        int has_dash_dash = 0;
@@ -973,7 +948,7 @@ static int parse_branchname_arg(int argc, const char **argv,
        if (!strcmp(arg, "-"))
                arg = "@{-1}";
 
-       if (get_sha1_mb(arg, rev)) {
+       if (get_oid_mb(arg, rev)) {
                /*
                 * Either case (3) or (4), with <something> not being
                 * a commit, or an attempt to use case (1) with an
@@ -1018,22 +993,22 @@ static int parse_branchname_arg(int argc, const char **argv,
        argv++;
        argc--;
 
-       new->name = arg;
-       setup_branch_path(new);
+       new_branch_info->name = arg;
+       setup_branch_path(new_branch_info);
 
-       if (!check_refname_format(new->path, 0) &&
-           !read_ref(new->path, branch_rev))
-               hashcpy(rev, branch_rev);
+       if (!check_refname_format(new_branch_info->path, 0) &&
+           !read_ref(new_branch_info->path, &branch_rev))
+               oidcpy(rev, &branch_rev);
        else
-               new->path = NULL; /* not an existing branch */
+               new_branch_info->path = NULL; /* not an existing branch */
 
-       new->commit = lookup_commit_reference_gently(rev, 1);
-       if (!new->commit) {
+       new_branch_info->commit = lookup_commit_reference_gently(rev, 1);
+       if (!new_branch_info->commit) {
                /* not a commit */
                *source_tree = parse_tree_indirect(rev);
        } else {
-               parse_commit_or_die(new->commit);
-               *source_tree = new->commit->tree;
+               parse_commit_or_die(new_branch_info->commit);
+               *source_tree = get_commit_tree(new_branch_info->commit);
        }
 
        if (!*source_tree)                   /* case (1): want a tree */
@@ -1073,7 +1048,7 @@ static int switch_unborn_to_new_branch(const struct checkout_opts *opts)
 }
 
 static int checkout_branch(struct checkout_opts *opts,
-                          struct branch_info *new)
+                          struct branch_info *new_branch_info)
 {
        if (opts->pathspec.nr)
                die(_("paths cannot be used with switching branches"));
@@ -1102,36 +1077,35 @@ static int checkout_branch(struct checkout_opts *opts,
        } else if (opts->track == BRANCH_TRACK_UNSPECIFIED)
                opts->track = git_branch_track;
 
-       if (new->name && !new->commit)
+       if (new_branch_info->name && !new_branch_info->commit)
                die(_("Cannot switch branch to a non-commit '%s'"),
-                   new->name);
+                   new_branch_info->name);
 
-       if (new->path && !opts->force_detach && !opts->new_branch &&
+       if (new_branch_info->path && !opts->force_detach && !opts->new_branch &&
            !opts->ignore_other_worktrees) {
-               unsigned char sha1[20];
                int flag;
-               char *head_ref = resolve_refdup("HEAD", 0, sha1, &flag);
+               char *head_ref = resolve_refdup("HEAD", 0, NULL, &flag);
                if (head_ref &&
-                   (!(flag & REF_ISSYMREF) || strcmp(head_ref, new->path)))
-                       die_if_checked_out(new->path, 1);
+                   (!(flag & REF_ISSYMREF) || strcmp(head_ref, new_branch_info->path)))
+                       die_if_checked_out(new_branch_info->path, 1);
                free(head_ref);
        }
 
-       if (!new->commit && opts->new_branch) {
-               unsigned char rev[20];
+       if (!new_branch_info->commit && opts->new_branch) {
+               struct object_id rev;
                int flag;
 
-               if (!read_ref_full("HEAD", 0, rev, &flag) &&
-                   (flag & REF_ISSYMREF) && is_null_sha1(rev))
+               if (!read_ref_full("HEAD", 0, &rev, &flag) &&
+                   (flag & REF_ISSYMREF) && is_null_oid(&rev))
                        return switch_unborn_to_new_branch(opts);
        }
-       return switch_branches(opts, new);
+       return switch_branches(opts, new_branch_info);
 }
 
 int cmd_checkout(int argc, const char **argv, const char *prefix)
 {
        struct checkout_opts opts;
-       struct branch_info new;
+       struct branch_info new_branch_info;
        char *conflict_style = NULL;
        int dwim_new_local_branch = 1;
        struct option options[] = {
@@ -1161,17 +1135,19 @@ int cmd_checkout(int argc, const char **argv, const char *prefix)
                                N_("second guess 'git checkout <no-such-branch>'")),
                OPT_BOOL(0, "ignore-other-worktrees", &opts.ignore_other_worktrees,
                         N_("do not check if another worktree is holding the given ref")),
+               { OPTION_CALLBACK, 0, "recurse-submodules", NULL,
+                           "checkout", "control recursive updating of submodules",
+                           PARSE_OPT_OPTARG, option_parse_recurse_submodules_worktree_updater },
                OPT_BOOL(0, "progress", &opts.show_progress, N_("force progress reporting")),
                OPT_END(),
        };
 
        memset(&opts, 0, sizeof(opts));
-       memset(&new, 0, sizeof(new));
+       memset(&new_branch_info, 0, sizeof(new_branch_info));
        opts.overwrite_ignore = 1;
        opts.prefix = prefix;
        opts.show_progress = -1;
 
-       gitmodules_config();
        git_config(git_checkout_config, &opts);
 
        opts.track = BRANCH_TRACK_UNSPECIFIED;
@@ -1232,14 +1208,14 @@ int cmd_checkout(int argc, const char **argv, const char *prefix)
         * remote branches, erroring out for invalid or ambiguous cases.
         */
        if (argc) {
-               unsigned char rev[20];
+               struct object_id rev;
                int dwim_ok =
                        !opts.patch_mode &&
                        dwim_new_local_branch &&
                        opts.track == BRANCH_TRACK_UNSPECIFIED &&
                        !opts.new_branch;
                int n = parse_branchname_arg(argc, argv, dwim_ok,
-                                            &new, &opts, rev);
+                                            &new_branch_info, &opts, &rev);
                argv += n;
                argc -= n;
        }
@@ -1257,9 +1233,8 @@ int cmd_checkout(int argc, const char **argv, const char *prefix)
                 * new_branch && argc > 1 will be caught later.
                 */
                if (opts.new_branch && argc == 1)
-                       die(_("Cannot update paths and switch to branch '%s' at the same time.\n"
-                             "Did you intend to checkout '%s' which can not be resolved as commit?"),
-                           opts.new_branch, argv[0]);
+                       die(_("'%s' is not a commit and a branch '%s' cannot be created from it"),
+                               argv[0], opts.new_branch);
 
                if (opts.force_detach)
                        die(_("git checkout: --detach does not take a path argument '%s'"),
@@ -1273,16 +1248,17 @@ int cmd_checkout(int argc, const char **argv, const char *prefix)
        if (opts.new_branch) {
                struct strbuf buf = STRBUF_INIT;
 
-               opts.branch_exists =
-                       validate_new_branchname(opts.new_branch, &buf,
-                                               !!opts.new_branch_force,
-                                               !!opts.new_branch_force);
-
+               if (opts.new_branch_force)
+                       opts.branch_exists = validate_branchname(opts.new_branch, &buf);
+               else
+                       opts.branch_exists =
+                               validate_new_branchname(opts.new_branch, &buf, 0);
                strbuf_release(&buf);
        }
 
+       UNLEAK(opts);
        if (opts.patch_mode || opts.pathspec.nr)
-               return checkout_paths(&opts, new.name);
+               return checkout_paths(&opts, new_branch_info.name);
        else
-               return checkout_branch(&opts, &new);
+               return checkout_branch(&opts, &new_branch_info);
 }