Merge branch 'tb/complete-sequencing'
[gitweb.git] / builtin / checkout.c
index 3e141fc1491949a2dbb47c59d7d156ae6fe4eb47..9b49f0e413ba03ebfee924d514a175d8f74fe1d3 100644 (file)
@@ -20,6 +20,7 @@
 #include "resolve-undo.h"
 #include "submodule.h"
 #include "argv-array.h"
+#include "sigchain.h"
 
 static const char * const checkout_usage[] = {
        N_("git checkout [<options>] <branch>"),
@@ -36,6 +37,7 @@ struct checkout_opts {
        int writeout_stage;
        int overwrite_ignore;
        int ignore_skipworktree;
+       int ignore_other_worktrees;
 
        const char *new_branch;
        const char *new_branch_force;
@@ -48,6 +50,10 @@ struct checkout_opts {
        const char *prefix;
        struct pathspec pathspec;
        struct tree *source_tree;
+
+       const char *new_worktree;
+       const char **saved_argv;
+       int new_worktree_mode;
 };
 
 static int post_checkout_hook(struct commit *old, struct commit *new,
@@ -267,6 +273,9 @@ static int checkout_paths(const struct checkout_opts *opts,
                die(_("Cannot update paths and switch to branch '%s' at the same time."),
                    opts->new_branch);
 
+       if (opts->new_worktree)
+               die(_("'%s' cannot be used with updating paths"), "--to");
+
        if (opts->patch_mode)
                return run_add_interactive(revision, "--patch=checkout",
                                           &opts->pathspec);
@@ -441,6 +450,11 @@ struct branch_info {
        const char *name; /* The short name used */
        const char *path; /* The full name of a real branch */
        struct commit *commit; /* The named commit */
+       /*
+        * if not null the branch is detached because it's already
+        * checked out in this checkout
+        */
+       char *checkout;
 };
 
 static void setup_branch_path(struct branch_info *branch)
@@ -502,7 +516,7 @@ 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 ?
+               tree = parse_tree_indirect(old->commit && !opts->new_worktree_mode ?
                                           old->commit->object.sha1 :
                                           EMPTY_TREE_SHA1_BIN);
                init_tree_desc(&trees[0], tree->buffer, tree->size);
@@ -606,18 +620,21 @@ static void update_refs_for_switch(const struct checkout_opts *opts,
                if (opts->new_orphan_branch) {
                        if (opts->new_branch_log && !log_all_ref_updates) {
                                int temp;
-                               char log_file[PATH_MAX];
-                               char *ref_name = mkpath("refs/heads/%s", opts->new_orphan_branch);
+                               struct strbuf log_file = STRBUF_INIT;
+                               int ret;
+                               const char *ref_name;
 
+                               ref_name = mkpath("refs/heads/%s", opts->new_orphan_branch);
                                temp = log_all_ref_updates;
                                log_all_ref_updates = 1;
-                               if (log_ref_setup(ref_name, log_file, sizeof(log_file))) {
+                               ret = log_ref_setup(ref_name, &log_file);
+                               log_all_ref_updates = temp;
+                               strbuf_release(&log_file);
+                               if (ret) {
                                        fprintf(stderr, _("Can not do reflog for '%s'\n"),
                                            opts->new_orphan_branch);
-                                       log_all_ref_updates = temp;
                                        return;
                                }
-                               log_all_ref_updates = temp;
                        }
                }
                else
@@ -685,10 +702,10 @@ static void update_refs_for_switch(const struct checkout_opts *opts,
 }
 
 static int add_pending_uninteresting_ref(const char *refname,
-                                        const unsigned char *sha1,
+                                        const struct object_id *oid,
                                         int flags, void *cb_data)
 {
-       add_pending_sha1(cb_data, refname, sha1, UNINTERESTING);
+       add_pending_sha1(cb_data, refname, oid->hash, UNINTERESTING);
        return 0;
 }
 
@@ -743,10 +760,17 @@ static void suggest_reattach(struct commit *commit, struct rev_info *revs)
 
        if (advice_detached_head)
                fprintf(stderr,
-                       _(
+                       Q_(
+                       /* The singular version */
+                       "If you want to keep it by creating a new branch, "
+                       "this may be a good time\nto do so with:\n\n"
+                       " git branch <new-branch-name> %s\n\n",
+                       /* The plural version */
                        "If you want to keep them by creating a new branch, "
                        "this may be a good time\nto do so with:\n\n"
-                       " git branch <new-branch-name> %s\n\n"),
+                       " git branch <new-branch-name> %s\n\n",
+                       /* Give ngettext() the count */
+                       lost),
                        find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV));
 }
 
@@ -815,7 +839,8 @@ static int switch_branches(const struct checkout_opts *opts,
                return ret;
        }
 
-       if (!opts->quiet && !old.path && old.commit && new->commit != old.commit)
+       if (!opts->quiet && !old.path && old.commit &&
+           new->commit != old.commit && !opts->new_worktree_mode)
                orphaned_commit_warning(old.commit, new->commit);
 
        update_refs_for_switch(opts, &old, new);
@@ -825,6 +850,138 @@ static int switch_branches(const struct checkout_opts *opts,
        return ret || writeout_error;
 }
 
+static char *junk_work_tree;
+static char *junk_git_dir;
+static int is_junk;
+static pid_t junk_pid;
+
+static void remove_junk(void)
+{
+       struct strbuf sb = STRBUF_INIT;
+       if (!is_junk || getpid() != junk_pid)
+               return;
+       if (junk_git_dir) {
+               strbuf_addstr(&sb, junk_git_dir);
+               remove_dir_recursively(&sb, 0);
+               strbuf_reset(&sb);
+       }
+       if (junk_work_tree) {
+               strbuf_addstr(&sb, junk_work_tree);
+               remove_dir_recursively(&sb, 0);
+       }
+       strbuf_release(&sb);
+}
+
+static void remove_junk_on_signal(int signo)
+{
+       remove_junk();
+       sigchain_pop(signo);
+       raise(signo);
+}
+
+static int prepare_linked_checkout(const struct checkout_opts *opts,
+                                  struct branch_info *new)
+{
+       struct strbuf sb_git = STRBUF_INIT, sb_repo = STRBUF_INIT;
+       struct strbuf sb = STRBUF_INIT;
+       const char *path = opts->new_worktree, *name;
+       struct stat st;
+       struct child_process cp;
+       int counter = 0, len, ret;
+
+       if (!new->commit)
+               die(_("no branch specified"));
+       if (file_exists(path) && !is_empty_dir(path))
+               die(_("'%s' already exists"), path);
+
+       len = strlen(path);
+       while (len && is_dir_sep(path[len - 1]))
+               len--;
+
+       for (name = path + len - 1; name > path; name--)
+               if (is_dir_sep(*name)) {
+                       name++;
+                       break;
+               }
+       strbuf_addstr(&sb_repo,
+                     git_path("worktrees/%.*s", (int)(path + len - name), name));
+       len = sb_repo.len;
+       if (safe_create_leading_directories_const(sb_repo.buf))
+               die_errno(_("could not create leading directories of '%s'"),
+                         sb_repo.buf);
+       while (!stat(sb_repo.buf, &st)) {
+               counter++;
+               strbuf_setlen(&sb_repo, len);
+               strbuf_addf(&sb_repo, "%d", counter);
+       }
+       name = strrchr(sb_repo.buf, '/') + 1;
+
+       junk_pid = getpid();
+       atexit(remove_junk);
+       sigchain_push_common(remove_junk_on_signal);
+
+       if (mkdir(sb_repo.buf, 0777))
+               die_errno(_("could not create directory of '%s'"), sb_repo.buf);
+       junk_git_dir = xstrdup(sb_repo.buf);
+       is_junk = 1;
+
+       /*
+        * lock the incomplete repo so prune won't delete it, unlock
+        * after the preparation is over.
+        */
+       strbuf_addf(&sb, "%s/locked", sb_repo.buf);
+       write_file(sb.buf, 1, "initializing\n");
+
+       strbuf_addf(&sb_git, "%s/.git", path);
+       if (safe_create_leading_directories_const(sb_git.buf))
+               die_errno(_("could not create leading directories of '%s'"),
+                         sb_git.buf);
+       junk_work_tree = xstrdup(path);
+
+       strbuf_reset(&sb);
+       strbuf_addf(&sb, "%s/gitdir", sb_repo.buf);
+       write_file(sb.buf, 1, "%s\n", real_path(sb_git.buf));
+       write_file(sb_git.buf, 1, "gitdir: %s/worktrees/%s\n",
+                  real_path(get_git_common_dir()), name);
+       /*
+        * This is to keep resolve_ref() happy. We need a valid HEAD
+        * or is_git_directory() will reject the directory. Any valid
+        * value would do because this value will be ignored and
+        * replaced at the next (real) checkout.
+        */
+       strbuf_reset(&sb);
+       strbuf_addf(&sb, "%s/HEAD", sb_repo.buf);
+       write_file(sb.buf, 1, "%s\n", sha1_to_hex(new->commit->object.sha1));
+       strbuf_reset(&sb);
+       strbuf_addf(&sb, "%s/commondir", sb_repo.buf);
+       write_file(sb.buf, 1, "../..\n");
+
+       if (!opts->quiet)
+               fprintf_ln(stderr, _("Enter %s (identifier %s)"), path, name);
+
+       setenv("GIT_CHECKOUT_NEW_WORKTREE", "1", 1);
+       setenv(GIT_DIR_ENVIRONMENT, sb_git.buf, 1);
+       setenv(GIT_WORK_TREE_ENVIRONMENT, path, 1);
+       memset(&cp, 0, sizeof(cp));
+       cp.git_cmd = 1;
+       cp.argv = opts->saved_argv;
+       ret = run_command(&cp);
+       if (!ret) {
+               is_junk = 0;
+               free(junk_work_tree);
+               free(junk_git_dir);
+               junk_work_tree = NULL;
+               junk_git_dir = NULL;
+       }
+       strbuf_reset(&sb);
+       strbuf_addf(&sb, "%s/locked", sb_repo.buf);
+       unlink_or_warn(sb.buf);
+       strbuf_release(&sb);
+       strbuf_release(&sb_repo);
+       strbuf_release(&sb_git);
+       return ret;
+}
+
 static int git_checkout_config(const char *var, const char *value, void *cb)
 {
        if (!strcmp(var, "diff.ignoresubmodules")) {
@@ -880,13 +1037,80 @@ static const char *unique_tracking_name(const char *name, unsigned char *sha1)
        return NULL;
 }
 
+static void check_linked_checkout(struct branch_info *new, const char *id)
+{
+       struct strbuf sb = STRBUF_INIT;
+       struct strbuf path = STRBUF_INIT;
+       struct strbuf gitdir = STRBUF_INIT;
+       const char *start, *end;
+
+       if (id)
+               strbuf_addf(&path, "%s/worktrees/%s/HEAD", get_git_common_dir(), id);
+       else
+               strbuf_addf(&path, "%s/HEAD", get_git_common_dir());
+
+       if (strbuf_read_file(&sb, path.buf, 0) < 0 ||
+           !skip_prefix(sb.buf, "ref:", &start))
+               goto done;
+       while (isspace(*start))
+               start++;
+       end = start;
+       while (*end && !isspace(*end))
+               end++;
+       if (strncmp(start, new->path, end - start) || new->path[end - start] != '\0')
+               goto done;
+       if (id) {
+               strbuf_reset(&path);
+               strbuf_addf(&path, "%s/worktrees/%s/gitdir", get_git_common_dir(), id);
+               if (strbuf_read_file(&gitdir, path.buf, 0) <= 0)
+                       goto done;
+               strbuf_rtrim(&gitdir);
+       } else
+               strbuf_addstr(&gitdir, get_git_common_dir());
+       die(_("'%s' is already checked out at '%s'"), new->name, gitdir.buf);
+done:
+       strbuf_release(&path);
+       strbuf_release(&sb);
+       strbuf_release(&gitdir);
+}
+
+static void check_linked_checkouts(struct branch_info *new)
+{
+       struct strbuf path = STRBUF_INIT;
+       DIR *dir;
+       struct dirent *d;
+
+       strbuf_addf(&path, "%s/worktrees", get_git_common_dir());
+       if ((dir = opendir(path.buf)) == NULL) {
+               strbuf_release(&path);
+               return;
+       }
+
+       /*
+        * $GIT_COMMON_DIR/HEAD is practically outside
+        * $GIT_DIR so resolve_ref_unsafe() won't work (it
+        * uses git_path). Parse the ref ourselves.
+        */
+       check_linked_checkout(new, NULL);
+
+       while ((d = readdir(dir)) != NULL) {
+               if (!strcmp(d->d_name, ".") || !strcmp(d->d_name, ".."))
+                       continue;
+               check_linked_checkout(new, d->d_name);
+       }
+       strbuf_release(&path);
+       closedir(dir);
+}
+
 static int parse_branchname_arg(int argc, const char **argv,
                                int dwim_new_local_branch_ok,
                                struct branch_info *new,
-                               struct tree **source_tree,
-                               unsigned char rev[20],
-                               const char **new_branch)
+                               struct checkout_opts *opts,
+                               unsigned char rev[20])
 {
+       struct tree **source_tree = &opts->source_tree;
+       const char **new_branch = &opts->new_branch;
+       int force_detach = opts->force_detach;
        int argcount = 0;
        unsigned char branch_rev[20];
        const char *arg;
@@ -1007,6 +1231,17 @@ static int parse_branchname_arg(int argc, const char **argv,
        else
                new->path = NULL; /* not an existing branch */
 
+       if (new->path && !force_detach && !*new_branch) {
+               unsigned char sha1[20];
+               int flag;
+               char *head_ref = resolve_refdup("HEAD", 0, sha1, &flag);
+               if (head_ref &&
+                   (!(flag & REF_ISSYMREF) || strcmp(head_ref, new->path)) &&
+                   !opts->ignore_other_worktrees)
+                       check_linked_checkouts(new);
+               free(head_ref);
+       }
+
        new->commit = lookup_commit_reference_gently(rev, 1);
        if (!new->commit) {
                /* not a commit */
@@ -1086,6 +1321,9 @@ static int checkout_branch(struct checkout_opts *opts,
                die(_("Cannot switch branch to a non-commit '%s'"),
                    new->name);
 
+       if (opts->new_worktree)
+               return prepare_linked_checkout(opts, new);
+
        if (!new->commit && opts->new_branch) {
                unsigned char rev[20];
                int flag;
@@ -1128,6 +1366,10 @@ int cmd_checkout(int argc, const char **argv, const char *prefix)
                         N_("do not limit pathspecs to sparse entries only")),
                OPT_HIDDEN_BOOL(0, "guess", &dwim_new_local_branch,
                                N_("second guess 'git checkout <no-such-branch>'")),
+               OPT_FILENAME(0, "to", &opts.new_worktree,
+                          N_("check a branch out in a separate working directory")),
+               OPT_BOOL(0, "ignore-other-worktrees", &opts.ignore_other_worktrees,
+                        N_("do not check if another worktree is holding the given ref")),
                OPT_END(),
        };
 
@@ -1136,6 +1378,9 @@ int cmd_checkout(int argc, const char **argv, const char *prefix)
        opts.overwrite_ignore = 1;
        opts.prefix = prefix;
 
+       opts.saved_argv = xmalloc(sizeof(const char *) * (argc + 2));
+       memcpy(opts.saved_argv, argv, sizeof(const char *) * (argc + 1));
+
        gitmodules_config();
        git_config(git_checkout_config, &opts);
 
@@ -1144,6 +1389,14 @@ int cmd_checkout(int argc, const char **argv, const char *prefix)
        argc = parse_options(argc, argv, prefix, options, checkout_usage,
                             PARSE_OPT_KEEP_DASHDASH);
 
+       /* recursive execution from checkout_new_worktree() */
+       opts.new_worktree_mode = getenv("GIT_CHECKOUT_NEW_WORKTREE") != NULL;
+       if (opts.new_worktree_mode)
+               opts.new_worktree = NULL;
+
+       if (!opts.new_worktree)
+               setup_work_tree();
+
        if (conflict_style) {
                opts.merge = 1; /* implied */
                git_xmerge_config("merge.conflictstyle", conflict_style, NULL);
@@ -1197,8 +1450,7 @@ int cmd_checkout(int argc, const char **argv, const char *prefix)
                        opts.track == BRANCH_TRACK_UNSPECIFIED &&
                        !opts.new_branch;
                int n = parse_branchname_arg(argc, argv, dwim_ok,
-                                            &new, &opts.source_tree,
-                                            rev, &opts.new_branch);
+                                            &new, &opts, rev);
                argv += n;
                argc -= n;
        }