root/builtin/worktree.c

DEFINITIONS

1. prune_worktree
2. prune_worktrees
3. prune
4. remove_junk
5. remove_junk_on_signal
6. worktree_basename
7. add_worktree
8. add
9. cmd_worktree

#include "cache.h"
#include "builtin.h"
#include "dir.h"
#include "parse-options.h"
#include "argv-array.h"
#include "branch.h"
#include "refs.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
};

struct add_opts {
        int force;
        int detach;
        const char *new_branch;
        int force_new_branch;
};

static int show_only;
static int verbose;
static unsigned long expire;

static int prune_worktree(const char *id, struct strbuf *reason)
{
        struct stat st;
        char *path;
        int fd, len;

        if (!is_directory(git_path("worktrees/%s", id))) {
                strbuf_addf(reason, _("Removing worktrees/%s: not a valid directory"), id);
                return 1;
        }
        if (file_exists(git_path("worktrees/%s/locked", id)))
                return 0;
        if (stat(git_path("worktrees/%s/gitdir", id), &st)) {
                strbuf_addf(reason, _("Removing worktrees/%s: gitdir file does not exist"), id);
                return 1;
        }
        fd = open(git_path("worktrees/%s/gitdir", id), O_RDONLY);
        if (fd < 0) {
                strbuf_addf(reason, _("Removing worktrees/%s: unable to read gitdir file (%s)"),
                            id, strerror(errno));
                return 1;
        }
        len = st.st_size;
        path = xmalloc(len + 1);
        read_in_full(fd, path, len);
        close(fd);
        while (len && (path[len - 1] == '\n' || path[len - 1] == '\r'))
                len--;
        if (!len) {
                strbuf_addf(reason, _("Removing worktrees/%s: invalid gitdir file"), id);
                free(path);
                return 1;
        }
        path[len] = '\0';
        if (!file_exists(path)) {
                struct stat st_link;
                free(path);
                /*
                 * the repo is moved manually and has not been
                 * accessed since?
                 */
                if (!stat(git_path("worktrees/%s/link", id), &st_link) &&
                    st_link.st_nlink > 1)
                        return 0;
                if (st.st_mtime <= expire) {
                        strbuf_addf(reason, _("Removing worktrees/%s: gitdir file points to non-existent location"), id);
                        return 1;
                } else {
                        return 0;
                }
        }
        free(path);
        return 0;
}

static void prune_worktrees(void)
{
        struct strbuf reason = STRBUF_INIT;
        struct strbuf path = STRBUF_INIT;
        DIR *dir = opendir(git_path("worktrees"));
        struct dirent *d;
        int ret;
        if (!dir)
                return;
        while ((d = readdir(dir)) != NULL) {
                if (!strcmp(d->d_name, ".") || !strcmp(d->d_name, ".."))
                        continue;
                strbuf_reset(&reason);
                if (!prune_worktree(d->d_name, &reason))
                        continue;
                if (show_only || verbose)
                        printf("%s\n", reason.buf);
                if (show_only)
                        continue;
                strbuf_reset(&path);
                strbuf_addstr(&path, git_path("worktrees/%s", d->d_name));
                ret = remove_dir_recursively(&path, 0);
                if (ret < 0 && errno == ENOTDIR)
                        ret = unlink(path.buf);
                if (ret)
                        error(_("failed to remove: %s"), strerror(errno));
        }
        closedir(dir);
        if (!show_only)
                rmdir(git_path("worktrees"));
        strbuf_release(&reason);
        strbuf_release(&path);
}

static int prune(int ac, const char **av, const char *prefix)
{
        struct option options[] = {
                OPT__DRY_RUN(&show_only, N_("do not remove, show only")),
                OPT__VERBOSE(&verbose, N_("report pruned objects")),
                OPT_EXPIRY_DATE(0, "expire", &expire,
                                N_("expire objects older than <time>")),
                OPT_END()
        };

        expire = ULONG_MAX;
        ac = parse_options(ac, av, prefix, options, worktree_usage, 0);
        if (ac)
                usage_with_options(worktree_usage, options);
        prune_worktrees();
        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 *refname,
                        const struct add_opts *opts)
{
        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;
        struct argv_array child_env = ARGV_ARRAY_INIT;
        int counter = 0, len, ret;
        struct strbuf symref = STRBUF_INIT;
        struct commit *commit = NULL;

        if (file_exists(path) && !is_empty_dir(path))
                die(_("'%s' already exists"), path);

        /* is 'refname' a branch or commit? */
        if (opts->force_new_branch) /* definitely a branch */
                ;
        else if (!opts->detach && !strbuf_check_branch_ref(&symref, refname) &&
                 ref_exists(symref.buf)) { /* it's a branch */
                if (!opts->force)
                        die_if_checked_out(symref.buf);
        } else { /* must be a commit */
                commit = lookup_commit_reference_by_name(refname);
                if (!commit)
                        die(_("invalid reference: %s"), refname);
        }

        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, "initializing");

        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, "%s", real_path(sb_git.buf));
        write_file(sb_git.buf, "gitdir: %s/worktrees/%s",
                   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 value which
         * looks like an object ID will do since it will be immediately
         * replaced by the symbolic-ref or update-ref invocation in the new
         * worktree.
         */
        strbuf_reset(&sb);
        strbuf_addf(&sb, "%s/HEAD", sb_repo.buf);
        write_file(sb.buf, "0000000000000000000000000000000000000000");
        strbuf_reset(&sb);
        strbuf_addf(&sb, "%s/commondir", sb_repo.buf);
        write_file(sb.buf, "../..");

        fprintf_ln(stderr, _("Preparing %s (identifier %s)"), path, name);

        argv_array_pushf(&child_env, "%s=%s", GIT_DIR_ENVIRONMENT, sb_git.buf);
        argv_array_pushf(&child_env, "%s=%s", GIT_WORK_TREE_ENVIRONMENT, path);
        memset(&cp, 0, sizeof(cp));
        cp.git_cmd = 1;

        if (commit)
                argv_array_pushl(&cp.args, "update-ref", "HEAD",
                                 sha1_to_hex(commit->object.sha1), NULL);
        else
                argv_array_pushl(&cp.args, "symbolic-ref", "HEAD",
                                 symref.buf, NULL);
        cp.env = child_env.argv;
        ret = run_command(&cp);
        if (ret)
                goto done;

        cp.argv = NULL;
        argv_array_clear(&cp.args);
        argv_array_pushl(&cp.args, "reset", "--hard", NULL);
        cp.env = child_env.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;
        }
done:
        strbuf_reset(&sb);
        strbuf_addf(&sb, "%s/locked", sb_repo.buf);
        unlink_or_warn(sb.buf);
        argv_array_clear(&child_env);
        strbuf_release(&sb);
        strbuf_release(&symref);
        strbuf_release(&sb_repo);
        strbuf_release(&sb_git);
        return ret;
}

static int add(int ac, const char **av, const char *prefix)
{
        struct add_opts opts;
        const char *new_branch_force = NULL;
        const char *path, *branch;
        struct option options[] = {
                OPT__FORCE(&opts.force, N_("checkout <branch> even if already checked out in other worktree")),
                OPT_STRING('b', NULL, &opts.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", &opts.detach, N_("detach HEAD at named commit")),
                OPT_END()
        };

        memset(&opts, 0, sizeof(opts));
        ac = parse_options(ac, av, prefix, options, worktree_usage, 0);
        if (!!opts.detach + !!opts.new_branch + !!new_branch_force > 1)
                die(_("-b, -B, and --detach 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];

        opts.force_new_branch = !!new_branch_force;
        if (opts.force_new_branch)
                opts.new_branch = new_branch_force;

        if (ac < 2 && !opts.new_branch && !opts.detach) {
                int n;
                const char *s = worktree_basename(path, &n);
                opts.new_branch = xstrndup(s, n);
        }

        if (opts.new_branch) {
                struct child_process cp;
                memset(&cp, 0, sizeof(cp));
                cp.git_cmd = 1;
                argv_array_push(&cp.args, "branch");
                if (opts.force_new_branch)
                        argv_array_push(&cp.args, "--force");
                argv_array_push(&cp.args, opts.new_branch);
                argv_array_push(&cp.args, branch);
                if (run_command(&cp))
                        return -1;
                branch = opts.new_branch;
        }

        return add_worktree(path, branch, &opts);
}

int cmd_worktree(int ac, const char **av, const char *prefix)
{
        struct option options[] = {
                OPT_END()
        };

        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);
}