builtin/worktree.c

   1 #include "cache.h"
   2 #include "builtin.h"
   3 #include "dir.h"
   4 #include "parse-options.h"
   5 #include "argv-array.h"
   6 #include "run-command.h"
   7 #include "sigchain.h"
   8
   9 static const char * const worktree_usage[] = {
  10         N_("git worktree add [<options>] <path> <branch>"),
  11         N_("git worktree prune [<options>]"),
  12         NULL
  13 };
  14
  15 struct add_opts {
  16         int force;
  17         int detach;
  18         const char *new_branch;
  19         int force_new_branch;
  20 };
  21
  22 static int show_only;
  23 static int verbose;
  24 static unsigned long expire;
  25
  26 static int prune_worktree(const char *id, struct strbuf *reason)
  27 {
  28         struct stat st;
  29         char *path;
  30         int fd, len;
  31
  32         if (!is_directory(git_path("worktrees/%s", id))) {
  33                 strbuf_addf(reason, _("Removing worktrees/%s: not a valid directory"), id);
  34                 return 1;
  35         }
  36         if (file_exists(git_path("worktrees/%s/locked", id)))
  37                 return 0;
  38         if (stat(git_path("worktrees/%s/gitdir", id), &st)) {
  39                 strbuf_addf(reason, _("Removing worktrees/%s: gitdir file does not exist"), id);
  40                 return 1;
  41         }
  42         fd = open(git_path("worktrees/%s/gitdir", id), O_RDONLY);
  43         if (fd < 0) {
  44                 strbuf_addf(reason, _("Removing worktrees/%s: unable to read gitdir file (%s)"),
  45                             id, strerror(errno));
  46                 return 1;
  47         }
  48         len = st.st_size;
  49         path = xmalloc(len + 1);
  50         read_in_full(fd, path, len);
  51         close(fd);
  52         while (len && (path[len - 1] == '\n' || path[len - 1] == '\r'))
  53                 len--;
  54         if (!len) {
  55                 strbuf_addf(reason, _("Removing worktrees/%s: invalid gitdir file"), id);
  56                 free(path);
  57                 return 1;
  58         }
  59         path[len] = '\0';
  60         if (!file_exists(path)) {
  61                 struct stat st_link;
  62                 free(path);
  63                 /*
  64                  * the repo is moved manually and has not been
  65                  * accessed since?
  66                  */
  67                 if (!stat(git_path("worktrees/%s/link", id), &st_link) &&
  68                     st_link.st_nlink > 1)
  69                         return 0;
  70                 if (st.st_mtime <= expire) {
  71                         strbuf_addf(reason, _("Removing worktrees/%s: gitdir file points to non-existent location"), id);
  72                         return 1;
  73                 } else {
  74                         return 0;
  75                 }
  76         }
  77         free(path);
  78         return 0;
  79 }
  80
  81 static void prune_worktrees(void)
  82 {
  83         struct strbuf reason = STRBUF_INIT;
  84         struct strbuf path = STRBUF_INIT;
  85         DIR *dir = opendir(git_path("worktrees"));
  86         struct dirent *d;
  87         int ret;
  88         if (!dir)
  89                 return;
  90         while ((d = readdir(dir)) != NULL) {
  91                 if (!strcmp(d->d_name, ".") || !strcmp(d->d_name, ".."))
  92                         continue;
  93                 strbuf_reset(&reason);
  94                 if (!prune_worktree(d->d_name, &reason))
  95                         continue;
  96                 if (show_only || verbose)
  97                         printf("%s\n", reason.buf);
  98                 if (show_only)
  99                         continue;
 100                 strbuf_reset(&path);
 101                 strbuf_addstr(&path, git_path("worktrees/%s", d->d_name));
 102                 ret = remove_dir_recursively(&path, 0);
 103                 if (ret < 0 && errno == ENOTDIR)
 104                         ret = unlink(path.buf);
 105                 if (ret)
 106                         error(_("failed to remove: %s"), strerror(errno));
 107         }
 108         closedir(dir);
 109         if (!show_only)
 110                 rmdir(git_path("worktrees"));
 111         strbuf_release(&reason);
 112         strbuf_release(&path);
 113 }
 114
 115 static int prune(int ac, const char **av, const char *prefix)
 116 {
 117         struct option options[] = {
 118                 OPT__DRY_RUN(&show_only, N_("do not remove, show only")),
 119                 OPT__VERBOSE(&verbose, N_("report pruned objects")),
 120                 OPT_EXPIRY_DATE(0, "expire", &expire,
 121                                 N_("expire objects older than <time>")),
 122                 OPT_END()
 123         };
 124
 125         expire = ULONG_MAX;
 126         ac = parse_options(ac, av, prefix, options, worktree_usage, 0);
 127         if (ac)
 128                 usage_with_options(worktree_usage, options);
 129         prune_worktrees();
 130         return 0;
 131 }
 132
 133 static char *junk_work_tree;
 134 static char *junk_git_dir;
 135 static int is_junk;
 136 static pid_t junk_pid;
 137
 138 static void remove_junk(void)
 139 {
 140         struct strbuf sb = STRBUF_INIT;
 141         if (!is_junk || getpid() != junk_pid)
 142                 return;
 143         if (junk_git_dir) {
 144                 strbuf_addstr(&sb, junk_git_dir);
 145                 remove_dir_recursively(&sb, 0);
 146                 strbuf_reset(&sb);
 147         }
 148         if (junk_work_tree) {
 149                 strbuf_addstr(&sb, junk_work_tree);
 150                 remove_dir_recursively(&sb, 0);
 151         }
 152         strbuf_release(&sb);
 153 }
 154
 155 static void remove_junk_on_signal(int signo)
 156 {
 157         remove_junk();
 158         sigchain_pop(signo);
 159         raise(signo);
 160 }
 161
 162 static const char *worktree_basename(const char *path, int *olen)
 163 {
 164         const char *name;
 165         int len;
 166
 167         len = strlen(path);
 168         while (len && is_dir_sep(path[len - 1]))
 169                 len--;
 170
 171         for (name = path + len - 1; name > path; name--)
 172                 if (is_dir_sep(*name)) {
 173                         name++;
 174                         break;
 175                 }
 176
 177         *olen = len;
 178         return name;
 179 }
 180
 181 static int add_worktree(const char *path, const char **child_argv,
 182                         const struct add_opts *opts)
 183 {
 184         struct strbuf sb_git = STRBUF_INIT, sb_repo = STRBUF_INIT;
 185         struct strbuf sb = STRBUF_INIT;
 186         const char *name;
 187         struct stat st;
 188         struct child_process cp;
 189         int counter = 0, len, ret;
 190         unsigned char rev[20];
 191
 192         if (file_exists(path) && !is_empty_dir(path))
 193                 die(_("'%s' already exists"), path);
 194
 195         name = worktree_basename(path, &len);
 196         strbuf_addstr(&sb_repo,
 197                       git_path("worktrees/%.*s", (int)(path + len - name), name));
 198         len = sb_repo.len;
 199         if (safe_create_leading_directories_const(sb_repo.buf))
 200                 die_errno(_("could not create leading directories of '%s'"),
 201                           sb_repo.buf);
 202         while (!stat(sb_repo.buf, &st)) {
 203                 counter++;
 204                 strbuf_setlen(&sb_repo, len);
 205                 strbuf_addf(&sb_repo, "%d", counter);
 206         }
 207         name = strrchr(sb_repo.buf, '/') + 1;
 208
 209         junk_pid = getpid();
 210         atexit(remove_junk);
 211         sigchain_push_common(remove_junk_on_signal);
 212
 213         if (mkdir(sb_repo.buf, 0777))
 214                 die_errno(_("could not create directory of '%s'"), sb_repo.buf);
 215         junk_git_dir = xstrdup(sb_repo.buf);
 216         is_junk = 1;
 217
 218         /*
 219          * lock the incomplete repo so prune won't delete it, unlock
 220          * after the preparation is over.
 221          */
 222         strbuf_addf(&sb, "%s/locked", sb_repo.buf);
 223         write_file(sb.buf, 1, "initializing\n");
 224
 225         strbuf_addf(&sb_git, "%s/.git", path);
 226         if (safe_create_leading_directories_const(sb_git.buf))
 227                 die_errno(_("could not create leading directories of '%s'"),
 228                           sb_git.buf);
 229         junk_work_tree = xstrdup(path);
 230
 231         strbuf_reset(&sb);
 232         strbuf_addf(&sb, "%s/gitdir", sb_repo.buf);
 233         write_file(sb.buf, 1, "%s\n", real_path(sb_git.buf));
 234         write_file(sb_git.buf, 1, "gitdir: %s/worktrees/%s\n",
 235                    real_path(get_git_common_dir()), name);
 236         /*
 237          * This is to keep resolve_ref() happy. We need a valid HEAD
 238          * or is_git_directory() will reject the directory. Moreover, HEAD
 239          * in the new worktree must resolve to the same value as HEAD in
 240          * the current tree since the command invoked to populate the new
 241          * worktree will be handed the branch/ref specified by the user.
 242          * For instance, if the user asks for the new worktree to be based
 243          * at HEAD~5, then the resolved HEAD~5 in the new worktree must
 244          * match the resolved HEAD~5 in the current tree in order to match
 245          * the user's expectation.
 246          */
 247         if (!resolve_ref_unsafe("HEAD", 0, rev, NULL))
 248                 die(_("unable to resolve HEAD"));
 249         strbuf_reset(&sb);
 250         strbuf_addf(&sb, "%s/HEAD", sb_repo.buf);
 251         write_file(sb.buf, 1, "%s\n", sha1_to_hex(rev));
 252         strbuf_reset(&sb);
 253         strbuf_addf(&sb, "%s/commondir", sb_repo.buf);
 254         write_file(sb.buf, 1, "../..\n");
 255
 256         fprintf_ln(stderr, _("Preparing %s (identifier %s)"), path, name);
 257
 258         setenv("GIT_CHECKOUT_NEW_WORKTREE", "1", 1);
 259         setenv(GIT_DIR_ENVIRONMENT, sb_git.buf, 1);
 260         setenv(GIT_WORK_TREE_ENVIRONMENT, path, 1);
 261         memset(&cp, 0, sizeof(cp));
 262         cp.git_cmd = 1;
 263         cp.argv = child_argv;
 264         ret = run_command(&cp);
 265         if (!ret) {
 266                 is_junk = 0;
 267                 free(junk_work_tree);
 268                 free(junk_git_dir);
 269                 junk_work_tree = NULL;
 270                 junk_git_dir = NULL;
 271         }
 272         strbuf_reset(&sb);
 273         strbuf_addf(&sb, "%s/locked", sb_repo.buf);
 274         unlink_or_warn(sb.buf);
 275         strbuf_release(&sb);
 276         strbuf_release(&sb_repo);
 277         strbuf_release(&sb_git);
 278         return ret;
 279 }
 280
 281 static int add(int ac, const char **av, const char *prefix)
 282 {
 283         struct add_opts opts;
 284         const char *new_branch_force = NULL;
 285         const char *path, *branch;
 286         struct argv_array cmd = ARGV_ARRAY_INIT;
 287         struct option options[] = {
 288                 OPT__FORCE(&opts.force, N_("checkout <branch> even if already checked out in other worktree")),
 289                 OPT_STRING('b', NULL, &opts.new_branch, N_("branch"),
 290                            N_("create a new branch")),
 291                 OPT_STRING('B', NULL, &new_branch_force, N_("branch"),
 292                            N_("create or reset a branch")),
 293                 OPT_BOOL(0, "detach", &opts.detach, N_("detach HEAD at named commit")),
 294                 OPT_END()
 295         };
 296
 297         memset(&opts, 0, sizeof(opts));
 298         ac = parse_options(ac, av, prefix, options, worktree_usage, 0);
 299         if (!!opts.detach + !!opts.new_branch + !!new_branch_force > 1)
 300                 die(_("-b, -B, and --detach are mutually exclusive"));
 301         if (ac < 1 || ac > 2)
 302                 usage_with_options(worktree_usage, options);
 303
 304         path = prefix ? prefix_filename(prefix, strlen(prefix), av[0]) : av[0];
 305         branch = ac < 2 ? "HEAD" : av[1];
 306
 307         opts.force_new_branch = !!new_branch_force;
 308         if (opts.force_new_branch)
 309                 opts.new_branch = new_branch_force;
 310
 311         if (ac < 2 && !opts.new_branch && !opts.detach) {
 312                 int n;
 313                 const char *s = worktree_basename(path, &n);
 314                 opts.new_branch = xstrndup(s, n);
 315         }
 316
 317         argv_array_push(&cmd, "checkout");
 318         if (opts.force)
 319                 argv_array_push(&cmd, "--ignore-other-worktrees");
 320         if (opts.new_branch)
 321                 argv_array_pushl(&cmd, opts.force_new_branch ? "-B" : "-b",
 322                                  opts.new_branch, NULL);
 323         if (opts.detach)
 324                 argv_array_push(&cmd, "--detach");
 325         argv_array_push(&cmd, branch);
 326
 327         return add_worktree(path, cmd.argv, &opts);
 328 }
 329
 330 int cmd_worktree(int ac, const char **av, const char *prefix)
 331 {
 332         struct option options[] = {
 333                 OPT_END()
 334         };
 335
 336         if (ac < 2)
 337                 usage_with_options(worktree_usage, options);
 338         if (!strcmp(av[1], "add"))
 339                 return add(ac - 1, av + 1, prefix);
 340         if (!strcmp(av[1], "prune"))
 341                 return prune(ac - 1, av + 1, prefix);
 342         usage_with_options(worktree_usage, options);
 343 }