Merge branch 'cc/trailers-corner-case-fix' into maint
[gitweb.git] / builtin / worktree.c
index 2a729c661cd3747ee345c8491dfc8ff540ee9c0f..6a264ee749221cd6c6bf98ce68790bdec3dd82c5 100644 (file)
@@ -2,8 +2,13 @@
 #include "builtin.h"
 #include "dir.h"
 #include "parse-options.h"
+#include "argv-array.h"
+#include "run-command.h"
+#include "sigchain.h"
+#include "refs.h"
 
 static const char * const worktree_usage[] = {
+       N_("git worktree add [<options>] <path> <branch>"),
        N_("git worktree prune [<options>]"),
        NULL
 };
@@ -119,6 +124,198 @@ static int prune(int ac, const char **av, const char *prefix)
        return 0;
 }
 
+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 const char *worktree_basename(const char *path, int *olen)
+{
+       const char *name;
+       int len;
+
+       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;
+               }
+
+       *olen = len;
+       return name;
+}
+
+static int add_worktree(const char *path, const char **child_argv)
+{
+       struct strbuf sb_git = STRBUF_INIT, sb_repo = STRBUF_INIT;
+       struct strbuf sb = STRBUF_INIT;
+       const char *name;
+       struct stat st;
+       struct child_process cp;
+       int counter = 0, len, ret;
+       unsigned char rev[20];
+
+       if (file_exists(path) && !is_empty_dir(path))
+               die(_("'%s' already exists"), path);
+
+       name = worktree_basename(path, &len);
+       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. Moreover, HEAD
+        * in the new worktree must resolve to the same value as HEAD in
+        * the current tree since the command invoked to populate the new
+        * worktree will be handed the branch/ref specified by the user.
+        * For instance, if the user asks for the new worktree to be based
+        * at HEAD~5, then the resolved HEAD~5 in the new worktree must
+        * match the resolved HEAD~5 in the current tree in order to match
+        * the user's expectation.
+        */
+       if (!resolve_ref_unsafe("HEAD", 0, rev, NULL))
+               die(_("unable to resolve HEAD"));
+       strbuf_reset(&sb);
+       strbuf_addf(&sb, "%s/HEAD", sb_repo.buf);
+       write_file(sb.buf, 1, "%s\n", sha1_to_hex(rev));
+       strbuf_reset(&sb);
+       strbuf_addf(&sb, "%s/commondir", sb_repo.buf);
+       write_file(sb.buf, 1, "../..\n");
+
+       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 = child_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 add(int ac, const char **av, const char *prefix)
+{
+       int force = 0, detach = 0;
+       const char *new_branch = NULL, *new_branch_force = NULL;
+       const char *path, *branch;
+       struct argv_array cmd = ARGV_ARRAY_INIT;
+       struct option options[] = {
+               OPT__FORCE(&force, N_("checkout <branch> even if already checked out in other worktree")),
+               OPT_STRING('b', NULL, &new_branch, N_("branch"),
+                          N_("create a new branch")),
+               OPT_STRING('B', NULL, &new_branch_force, N_("branch"),
+                          N_("create or reset a branch")),
+               OPT_BOOL(0, "detach", &detach, N_("detach HEAD at named commit")),
+               OPT_END()
+       };
+
+       ac = parse_options(ac, av, prefix, options, worktree_usage, 0);
+       if (new_branch && new_branch_force)
+               die(_("-b and -B are mutually exclusive"));
+       if (ac < 1 || ac > 2)
+               usage_with_options(worktree_usage, options);
+
+       path = prefix ? prefix_filename(prefix, strlen(prefix), av[0]) : av[0];
+       branch = ac < 2 ? "HEAD" : av[1];
+
+       if (ac < 2 && !new_branch && !new_branch_force) {
+               int n;
+               const char *s = worktree_basename(path, &n);
+               new_branch = xstrndup(s, n);
+       }
+
+       argv_array_push(&cmd, "checkout");
+       if (force)
+               argv_array_push(&cmd, "--ignore-other-worktrees");
+       if (new_branch)
+               argv_array_pushl(&cmd, "-b", new_branch, NULL);
+       if (new_branch_force)
+               argv_array_pushl(&cmd, "-B", new_branch_force, NULL);
+       if (detach)
+               argv_array_push(&cmd, "--detach");
+       argv_array_push(&cmd, branch);
+
+       return add_worktree(path, cmd.argv);
+}
+
 int cmd_worktree(int ac, const char **av, const char *prefix)
 {
        struct option options[] = {
@@ -127,6 +324,8 @@ int cmd_worktree(int ac, const char **av, const char *prefix)
 
        if (ac < 2)
                usage_with_options(worktree_usage, options);
+       if (!strcmp(av[1], "add"))
+               return add(ac - 1, av + 1, prefix);
        if (!strcmp(av[1], "prune"))
                return prune(ac - 1, av + 1, prefix);
        usage_with_options(worktree_usage, options);