Merge branch 'jk/clone-allow-bare-and-o-together'

[thirdparty/git.git] / builtin / stash.c

#define USE_THE_INDEX_COMPATIBILITY_MACROS
#include "builtin.h"
#include "config.h"
#include "parse-options.h"
#include "refs.h"
#include "lockfile.h"
#include "cache-tree.h"
#include "unpack-trees.h"
#include "merge-recursive.h"
#include "merge-ort-wrappers.h"
#include "strvec.h"
#include "run-command.h"
#include "dir.h"
#include "entry.h"
#include "rerere.h"
#include "revision.h"
#include "log-tree.h"
#include "diffcore.h"
#include "exec-cmd.h"
#include "reflog.h"

#define INCLUDE_ALL_FILES 2

static const char * const git_stash_usage[] = {
        N_("git stash list [<options>]"),
        N_("git stash show [<options>] [<stash>]"),
        N_("git stash drop [-q|--quiet] [<stash>]"),
        N_("git stash ( pop | apply ) [--index] [-q|--quiet] [<stash>]"),
        N_("git stash branch <branchname> [<stash>]"),
        "git stash clear",
        N_("git stash [push [-p|--patch] [-S|--staged] [-k|--[no-]keep-index] [-q|--quiet]\n"
           "          [-u|--include-untracked] [-a|--all] [-m|--message <message>]\n"
           "          [--pathspec-from-file=<file> [--pathspec-file-nul]]\n"
           "          [--] [<pathspec>...]]"),
        N_("git stash save [-p|--patch] [-S|--staged] [-k|--[no-]keep-index] [-q|--quiet]\n"
           "          [-u|--include-untracked] [-a|--all] [<message>]"),
        NULL
};

static const char * const git_stash_list_usage[] = {
        N_("git stash list [<options>]"),
        NULL
};

static const char * const git_stash_show_usage[] = {
        N_("git stash show [<options>] [<stash>]"),
        NULL
};

static const char * const git_stash_drop_usage[] = {
        N_("git stash drop [-q|--quiet] [<stash>]"),
        NULL
};

static const char * const git_stash_pop_usage[] = {
        N_("git stash pop [--index] [-q|--quiet] [<stash>]"),
        NULL
};

static const char * const git_stash_apply_usage[] = {
        N_("git stash apply [--index] [-q|--quiet] [<stash>]"),
        NULL
};

static const char * const git_stash_branch_usage[] = {
        N_("git stash branch <branchname> [<stash>]"),
        NULL
};

static const char * const git_stash_clear_usage[] = {
        "git stash clear",
        NULL
};

static const char * const git_stash_store_usage[] = {
        N_("git stash store [-m|--message <message>] [-q|--quiet] <commit>"),
        NULL
};

static const char * const git_stash_push_usage[] = {
        N_("git stash [push [-p|--patch] [-k|--[no-]keep-index] [-q|--quiet]\n"
           "          [-u|--include-untracked] [-a|--all] [-m|--message <message>]\n"
           "          [--] [<pathspec>...]]"),
        NULL
};

static const char * const git_stash_save_usage[] = {
        N_("git stash save [-p|--patch] [-k|--[no-]keep-index] [-q|--quiet]\n"
           "               [-u|--include-untracked] [-a|--all] [<message>]"),
        NULL
};

static const char ref_stash[] = "refs/stash";
static struct strbuf stash_index_path = STRBUF_INIT;

/*
 * w_commit is set to the commit containing the working tree
 * b_commit is set to the base commit
 * i_commit is set to the commit containing the index tree
 * u_commit is set to the commit containing the untracked files tree
 * w_tree is set to the working tree
 * b_tree is set to the base tree
 * i_tree is set to the index tree
 * u_tree is set to the untracked files tree
 */
struct stash_info {
        struct object_id w_commit;
        struct object_id b_commit;
        struct object_id i_commit;
        struct object_id u_commit;
        struct object_id w_tree;
        struct object_id b_tree;
        struct object_id i_tree;
        struct object_id u_tree;
        struct strbuf revision;
        int is_stash_ref;
        int has_u;
};

#define STASH_INFO_INIT { \
        .revision = STRBUF_INIT, \
}

static void free_stash_info(struct stash_info *info)
{
        strbuf_release(&info->revision);
}

static void assert_stash_like(struct stash_info *info, const char *revision)
{
        if (get_oidf(&info->b_commit, "%s^1", revision) ||
            get_oidf(&info->w_tree, "%s:", revision) ||
            get_oidf(&info->b_tree, "%s^1:", revision) ||
            get_oidf(&info->i_tree, "%s^2:", revision))
                die(_("'%s' is not a stash-like commit"), revision);
}

static int get_stash_info(struct stash_info *info, int argc, const char **argv)
{
        int ret;
        char *end_of_rev;
        char *expanded_ref;
        const char *revision;
        const char *commit = NULL;
        struct object_id dummy;
        struct strbuf symbolic = STRBUF_INIT;

        if (argc > 1) {
                int i;
                struct strbuf refs_msg = STRBUF_INIT;

                for (i = 0; i < argc; i++)
                        strbuf_addf(&refs_msg, " '%s'", argv[i]);

                fprintf_ln(stderr, _("Too many revisions specified:%s"),
                           refs_msg.buf);
                strbuf_release(&refs_msg);

                return -1;
        }

        if (argc == 1)
                commit = argv[0];

        if (!commit) {
                if (!ref_exists(ref_stash)) {
                        fprintf_ln(stderr, _("No stash entries found."));
                        return -1;
                }

                strbuf_addf(&info->revision, "%s@{0}", ref_stash);
        } else if (strspn(commit, "0123456789") == strlen(commit)) {
                strbuf_addf(&info->revision, "%s@{%s}", ref_stash, commit);
        } else {
                strbuf_addstr(&info->revision, commit);
        }

        revision = info->revision.buf;

        if (get_oid(revision, &info->w_commit))
                return error(_("%s is not a valid reference"), revision);

        assert_stash_like(info, revision);

        info->has_u = !get_oidf(&info->u_tree, "%s^3:", revision);

        end_of_rev = strchrnul(revision, '@');
        strbuf_add(&symbolic, revision, end_of_rev - revision);

        ret = dwim_ref(symbolic.buf, symbolic.len, &dummy, &expanded_ref, 0);
        strbuf_release(&symbolic);
        switch (ret) {
        case 0: /* Not found, but valid ref */
                info->is_stash_ref = 0;
                break;
        case 1:
                info->is_stash_ref = !strcmp(expanded_ref, ref_stash);
                break;
        default: /* Invalid or ambiguous */
                break;
        }

        free(expanded_ref);
        return !(ret == 0 || ret == 1);
}

static int do_clear_stash(void)
{
        struct object_id obj;
        if (get_oid(ref_stash, &obj))
                return 0;

        return delete_ref(NULL, ref_stash, &obj, 0);
}

static int clear_stash(int argc, const char **argv, const char *prefix)
{
        struct option options[] = {
                OPT_END()
        };

        argc = parse_options(argc, argv, prefix, options,
                             git_stash_clear_usage,
                             PARSE_OPT_STOP_AT_NON_OPTION);

        if (argc)
                return error(_("git stash clear with arguments is "
                               "unimplemented"));

        return do_clear_stash();
}

static int reset_tree(struct object_id *i_tree, int update, int reset)
{
        int nr_trees = 1;
        struct unpack_trees_options opts;
        struct tree_desc t[MAX_UNPACK_TREES];
        struct tree *tree;
        struct lock_file lock_file = LOCK_INIT;

        read_cache_preload(NULL);
        if (refresh_cache(REFRESH_QUIET))
                return -1;

        hold_locked_index(&lock_file, LOCK_DIE_ON_ERROR);

        memset(&opts, 0, sizeof(opts));

        tree = parse_tree_indirect(i_tree);
        if (parse_tree(tree))
                return -1;

        init_tree_desc(t, tree->buffer, tree->size);

        opts.head_idx = 1;
        opts.src_index = &the_index;
        opts.dst_index = &the_index;
        opts.merge = 1;
        opts.reset = reset ? UNPACK_RESET_PROTECT_UNTRACKED : 0;
        opts.update = update;
        if (update)
                opts.preserve_ignored = 0; /* FIXME: !overwrite_ignore */
        opts.fn = oneway_merge;

        if (unpack_trees(nr_trees, t, &opts))
                return -1;

        if (write_locked_index(&the_index, &lock_file, COMMIT_LOCK))
                return error(_("unable to write new index file"));

        return 0;
}

static int diff_tree_binary(struct strbuf *out, struct object_id *w_commit)
{
        struct child_process cp = CHILD_PROCESS_INIT;
        const char *w_commit_hex = oid_to_hex(w_commit);

        /*
         * Diff-tree would not be very hard to replace with a native function,
         * however it should be done together with apply_cached.
         */
        cp.git_cmd = 1;
        strvec_pushl(&cp.args, "diff-tree", "--binary", NULL);
        strvec_pushf(&cp.args, "%s^2^..%s^2", w_commit_hex, w_commit_hex);

        return pipe_command(&cp, NULL, 0, out, 0, NULL, 0);
}

static int apply_cached(struct strbuf *out)
{
        struct child_process cp = CHILD_PROCESS_INIT;

        /*
         * Apply currently only reads either from stdin or a file, thus
         * apply_all_patches would have to be updated to optionally take a
         * buffer.
         */
        cp.git_cmd = 1;
        strvec_pushl(&cp.args, "apply", "--cached", NULL);
        return pipe_command(&cp, out->buf, out->len, NULL, 0, NULL, 0);
}

static int reset_head(void)
{
        struct child_process cp = CHILD_PROCESS_INIT;

        /*
         * Reset is overall quite simple, however there is no current public
         * API for resetting.
         */
        cp.git_cmd = 1;
        strvec_pushl(&cp.args, "reset", "--quiet", "--refresh", NULL);

        return run_command(&cp);
}

static int is_path_a_directory(const char *path)
{
        /*
         * This function differs from abspath.c:is_directory() in that
         * here we use lstat() instead of stat(); we do not want to
         * follow symbolic links here.
         */
        struct stat st;
        return (!lstat(path, &st) && S_ISDIR(st.st_mode));
}

static void add_diff_to_buf(struct diff_queue_struct *q,
                            struct diff_options *options,
                            void *data)
{
        int i;

        for (i = 0; i < q->nr; i++) {
                if (is_path_a_directory(q->queue[i]->one->path))
                        continue;

                strbuf_addstr(data, q->queue[i]->one->path);

                /* NUL-terminate: will be fed to update-index -z */
                strbuf_addch(data, '\0');
        }
}

static int restore_untracked(struct object_id *u_tree)
{
        int res;
        struct child_process cp = CHILD_PROCESS_INIT;

        /*
         * We need to run restore files from a given index, but without
         * affecting the current index, so we use GIT_INDEX_FILE with
         * run_command to fork processes that will not interfere.
         */
        cp.git_cmd = 1;
        strvec_push(&cp.args, "read-tree");
        strvec_push(&cp.args, oid_to_hex(u_tree));
        strvec_pushf(&cp.env, "GIT_INDEX_FILE=%s",
                     stash_index_path.buf);
        if (run_command(&cp)) {
                remove_path(stash_index_path.buf);
                return -1;
        }

        child_process_init(&cp);
        cp.git_cmd = 1;
        strvec_pushl(&cp.args, "checkout-index", "--all", NULL);
        strvec_pushf(&cp.env, "GIT_INDEX_FILE=%s",
                     stash_index_path.buf);

        res = run_command(&cp);
        remove_path(stash_index_path.buf);
        return res;
}

static void unstage_changes_unless_new(struct object_id *orig_tree)
{
        /*
         * When we enter this function, there has been a clean merge of
         * relevant trees, and the merge logic always stages whatever merges
         * cleanly.  We want to unstage those changes, unless it corresponds
         * to a file that didn't exist as of orig_tree.
         *
         * However, if any SKIP_WORKTREE path is modified relative to
         * orig_tree, then we want to clear the SKIP_WORKTREE bit and write
         * it to the worktree before unstaging.
         */

        struct checkout state = CHECKOUT_INIT;
        struct diff_options diff_opts;
        struct lock_file lock = LOCK_INIT;
        int i;

        /* If any entries have skip_worktree set, we'll have to check 'em out */
        state.force = 1;
        state.quiet = 1;
        state.refresh_cache = 1;
        state.istate = &the_index;

        /*
         * Step 1: get a difference between orig_tree (which corresponding
         * to the index before a merge was run) and the current index
         * (reflecting the changes brought in by the merge).
         */
        diff_setup(&diff_opts);
        diff_opts.flags.recursive = 1;
        diff_opts.detect_rename = 0;
        diff_opts.output_format = DIFF_FORMAT_NO_OUTPUT;
        diff_setup_done(&diff_opts);

        do_diff_cache(orig_tree, &diff_opts);
        diffcore_std(&diff_opts);

        /* Iterate over the paths that changed due to the merge... */
        for (i = 0; i < diff_queued_diff.nr; i++) {
                struct diff_filepair *p;
                struct cache_entry *ce;
                int pos;

                /* Look up the path's position in the current index. */
                p = diff_queued_diff.queue[i];
                pos = index_name_pos(&the_index, p->two->path,
                                     strlen(p->two->path));

                /*
                 * Step 2: Place changes in the working tree
                 *
                 * Stash is about restoring changes *to the working tree*.
                 * So if the merge successfully got a new version of some
                 * path, but left it out of the working tree, then clear the
                 * SKIP_WORKTREE bit and write it to the working tree.
                 */
                if (pos >= 0 && ce_skip_worktree(active_cache[pos])) {
                        struct stat st;

                        ce = active_cache[pos];
                        if (!lstat(ce->name, &st)) {
                                /* Conflicting path present; relocate it */
                                struct strbuf new_path = STRBUF_INIT;
                                int fd;

                                strbuf_addf(&new_path,
                                            "%s.stash.XXXXXX", ce->name);
                                fd = xmkstemp(new_path.buf);
                                close(fd);
                                printf(_("WARNING: Untracked file in way of "
                                         "tracked file!  Renaming\n "
                                         "           %s -> %s\n"
                                         "         to make room.\n"),
                                       ce->name, new_path.buf);
                                if (rename(ce->name, new_path.buf))
                                        die("Failed to move %s to %s\n",
                                            ce->name, new_path.buf);
                                strbuf_release(&new_path);
                        }
                        checkout_entry(ce, &state, NULL, NULL);
                        ce->ce_flags &= ~CE_SKIP_WORKTREE;
                }

                /*
                 * Step 3: "unstage" changes, as long as they are still tracked
                 */
                if (p->one->oid_valid) {
                        /*
                         * Path existed in orig_tree; restore index entry
                         * from that tree in order to "unstage" the changes.
                         */
                        int option = ADD_CACHE_OK_TO_REPLACE;
                        if (pos < 0)
                                option = ADD_CACHE_OK_TO_ADD;

                        ce = make_cache_entry(&the_index,
                                              p->one->mode,
                                              &p->one->oid,
                                              p->one->path,
                                              0, 0);
                        add_index_entry(&the_index, ce, option);
                }
        }
        diff_flush(&diff_opts);

        /*
         * Step 4: write the new index to disk
         */
        repo_hold_locked_index(the_repository, &lock, LOCK_DIE_ON_ERROR);
        if (write_locked_index(&the_index, &lock,
                               COMMIT_LOCK | SKIP_IF_UNCHANGED))
                die(_("Unable to write index."));
}

static int do_apply_stash(const char *prefix, struct stash_info *info,
                          int index, int quiet)
{
        int clean, ret;
        int has_index = index;
        struct merge_options o;
        struct object_id c_tree;
        struct object_id index_tree;
        struct tree *head, *merge, *merge_base;
        struct lock_file lock = LOCK_INIT;

        read_cache_preload(NULL);
        if (refresh_and_write_cache(REFRESH_QUIET, 0, 0))
                return -1;

        if (write_cache_as_tree(&c_tree, 0, NULL))
                return error(_("cannot apply a stash in the middle of a merge"));

        if (index) {
                if (oideq(&info->b_tree, &info->i_tree) ||
                    oideq(&c_tree, &info->i_tree)) {
                        has_index = 0;
                } else {
                        struct strbuf out = STRBUF_INIT;

                        if (diff_tree_binary(&out, &info->w_commit)) {
                                strbuf_release(&out);
                                return error(_("could not generate diff %s^!."),
                                             oid_to_hex(&info->w_commit));
                        }

                        ret = apply_cached(&out);
                        strbuf_release(&out);
                        if (ret)
                                return error(_("conflicts in index. "
                                               "Try without --index."));

                        discard_cache();
                        read_cache();
                        if (write_cache_as_tree(&index_tree, 0, NULL))
                                return error(_("could not save index tree"));

                        reset_head();
                        discard_cache();
                        read_cache();
                }
        }

        init_merge_options(&o, the_repository);

        o.branch1 = "Updated upstream";
        o.branch2 = "Stashed changes";
        o.ancestor = "Stash base";

        if (oideq(&info->b_tree, &c_tree))
                o.branch1 = "Version stash was based on";

        if (quiet)
                o.verbosity = 0;

        if (o.verbosity >= 3)
                printf_ln(_("Merging %s with %s"), o.branch1, o.branch2);

        head = lookup_tree(o.repo, &c_tree);
        merge = lookup_tree(o.repo, &info->w_tree);
        merge_base = lookup_tree(o.repo, &info->b_tree);

        repo_hold_locked_index(o.repo, &lock, LOCK_DIE_ON_ERROR);
        clean = merge_ort_nonrecursive(&o, head, merge, merge_base);

        /*
         * If 'clean' >= 0, reverse the value for 'ret' so 'ret' is 0 when the
         * merge was clean, and nonzero if the merge was unclean or encountered
         * an error.
         */
        ret = clean >= 0 ? !clean : clean;

        if (ret < 0)
                rollback_lock_file(&lock);
        else if (write_locked_index(o.repo->index, &lock,
                                      COMMIT_LOCK | SKIP_IF_UNCHANGED))
                ret = error(_("could not write index"));

        if (ret) {
                rerere(0);

                if (index)
                        fprintf_ln(stderr, _("Index was not unstashed."));

                goto restore_untracked;
        }

        if (has_index) {
                if (reset_tree(&index_tree, 0, 0))
                        ret = -1;
        } else {
                unstage_changes_unless_new(&c_tree);
        }

restore_untracked:
        if (info->has_u && restore_untracked(&info->u_tree))
                ret = error(_("could not restore untracked files from stash"));

        if (!quiet) {
                struct child_process cp = CHILD_PROCESS_INIT;

                /*
                 * Status is quite simple and could be replaced with calls to
                 * wt_status in the future, but it adds complexities which may
                 * require more tests.
                 */
                cp.git_cmd = 1;
                cp.dir = prefix;
                strvec_pushf(&cp.env, GIT_WORK_TREE_ENVIRONMENT"=%s",
                             absolute_path(get_git_work_tree()));
                strvec_pushf(&cp.env, GIT_DIR_ENVIRONMENT"=%s",
                             absolute_path(get_git_dir()));
                strvec_push(&cp.args, "status");
                run_command(&cp);
        }

        return ret;
}

static int apply_stash(int argc, const char **argv, const char *prefix)
{
        int ret = -1;
        int quiet = 0;
        int index = 0;
        struct stash_info info = STASH_INFO_INIT;
        struct option options[] = {
                OPT__QUIET(&quiet, N_("be quiet, only report errors")),
                OPT_BOOL(0, "index", &index,
                         N_("attempt to recreate the index")),
                OPT_END()
        };

        argc = parse_options(argc, argv, prefix, options,
                             git_stash_apply_usage, 0);

        if (get_stash_info(&info, argc, argv))
                goto cleanup;

        ret = do_apply_stash(prefix, &info, index, quiet);
cleanup:
        free_stash_info(&info);
        return ret;
}

static int reject_reflog_ent(struct object_id *ooid UNUSED,
                             struct object_id *noid UNUSED,
                             const char *email UNUSED,
                             timestamp_t timestamp UNUSED,
                             int tz UNUSED, const char *message UNUSED,
                             void *cb_data UNUSED)
{
        return 1;
}

static int reflog_is_empty(const char *refname)
{
        return !for_each_reflog_ent(refname, reject_reflog_ent, NULL);
}

static int do_drop_stash(struct stash_info *info, int quiet)
{
        if (!reflog_delete(info->revision.buf,
                           EXPIRE_REFLOGS_REWRITE | EXPIRE_REFLOGS_UPDATE_REF,
                           0)) {
                if (!quiet)
                        printf_ln(_("Dropped %s (%s)"), info->revision.buf,
                                  oid_to_hex(&info->w_commit));
        } else {
                return error(_("%s: Could not drop stash entry"),
                             info->revision.buf);
        }

        if (reflog_is_empty(ref_stash))
                do_clear_stash();

        return 0;
}

static int get_stash_info_assert(struct stash_info *info, int argc,
                                 const char **argv)
{
        int ret = get_stash_info(info, argc, argv);

        if (ret < 0)
                return ret;

        if (!info->is_stash_ref)
                return error(_("'%s' is not a stash reference"), info->revision.buf);

        return 0;
}

static int drop_stash(int argc, const char **argv, const char *prefix)
{
        int ret = -1;
        int quiet = 0;
        struct stash_info info = STASH_INFO_INIT;
        struct option options[] = {
                OPT__QUIET(&quiet, N_("be quiet, only report errors")),
                OPT_END()
        };

        argc = parse_options(argc, argv, prefix, options,
                             git_stash_drop_usage, 0);

        if (get_stash_info_assert(&info, argc, argv))
                goto cleanup;

        ret = do_drop_stash(&info, quiet);
cleanup:
        free_stash_info(&info);
        return ret;
}

static int pop_stash(int argc, const char **argv, const char *prefix)
{
        int ret = -1;
        int index = 0;
        int quiet = 0;
        struct stash_info info = STASH_INFO_INIT;
        struct option options[] = {
                OPT__QUIET(&quiet, N_("be quiet, only report errors")),
                OPT_BOOL(0, "index", &index,
                         N_("attempt to recreate the index")),
                OPT_END()
        };

        argc = parse_options(argc, argv, prefix, options,
                             git_stash_pop_usage, 0);

        if (get_stash_info_assert(&info, argc, argv))
                goto cleanup;

        if ((ret = do_apply_stash(prefix, &info, index, quiet)))
                printf_ln(_("The stash entry is kept in case "
                            "you need it again."));
        else
                ret = do_drop_stash(&info, quiet);

cleanup:
        free_stash_info(&info);
        return ret;
}

static int branch_stash(int argc, const char **argv, const char *prefix)
{
        int ret = -1;
        const char *branch = NULL;
        struct stash_info info = STASH_INFO_INIT;
        struct child_process cp = CHILD_PROCESS_INIT;
        struct option options[] = {
                OPT_END()
        };

        argc = parse_options(argc, argv, prefix, options,
                             git_stash_branch_usage, 0);

        if (!argc) {
                fprintf_ln(stderr, _("No branch name specified"));
                return -1;
        }

        branch = argv[0];

        if (get_stash_info(&info, argc - 1, argv + 1))
                goto cleanup;

        cp.git_cmd = 1;
        strvec_pushl(&cp.args, "checkout", "-b", NULL);
        strvec_push(&cp.args, branch);
        strvec_push(&cp.args, oid_to_hex(&info.b_commit));
        ret = run_command(&cp);
        if (!ret)
                ret = do_apply_stash(prefix, &info, 1, 0);
        if (!ret && info.is_stash_ref)
                ret = do_drop_stash(&info, 0);

cleanup:
        free_stash_info(&info);
        return ret;
}

static int list_stash(int argc, const char **argv, const char *prefix)
{
        struct child_process cp = CHILD_PROCESS_INIT;
        struct option options[] = {
                OPT_END()
        };

        argc = parse_options(argc, argv, prefix, options,
                             git_stash_list_usage,
                             PARSE_OPT_KEEP_UNKNOWN_OPT);

        if (!ref_exists(ref_stash))
                return 0;

        cp.git_cmd = 1;
        strvec_pushl(&cp.args, "log", "--format=%gd: %gs", "-g",
                     "--first-parent", NULL);
        strvec_pushv(&cp.args, argv);
        strvec_push(&cp.args, ref_stash);
        strvec_push(&cp.args, "--");
        return run_command(&cp);
}

static int show_stat = 1;
static int show_patch;
static int show_include_untracked;

static int git_stash_config(const char *var, const char *value, void *cb)
{
        if (!strcmp(var, "stash.showstat")) {
                show_stat = git_config_bool(var, value);
                return 0;
        }
        if (!strcmp(var, "stash.showpatch")) {
                show_patch = git_config_bool(var, value);
                return 0;
        }
        if (!strcmp(var, "stash.showincludeuntracked")) {
                show_include_untracked = git_config_bool(var, value);
                return 0;
        }
        return git_diff_basic_config(var, value, cb);
}

static void diff_include_untracked(const struct stash_info *info, struct diff_options *diff_opt)
{
        const struct object_id *oid[] = { &info->w_commit, &info->u_tree };
        struct tree *tree[ARRAY_SIZE(oid)];
        struct tree_desc tree_desc[ARRAY_SIZE(oid)];
        struct unpack_trees_options unpack_tree_opt = { 0 };
        int i;

        for (i = 0; i < ARRAY_SIZE(oid); i++) {
                tree[i] = parse_tree_indirect(oid[i]);
                if (parse_tree(tree[i]) < 0)
                        die(_("failed to parse tree"));
                init_tree_desc(&tree_desc[i], tree[i]->buffer, tree[i]->size);
        }

        unpack_tree_opt.head_idx = -1;
        unpack_tree_opt.src_index = &the_index;
        unpack_tree_opt.dst_index = &the_index;
        unpack_tree_opt.merge = 1;
        unpack_tree_opt.fn = stash_worktree_untracked_merge;

        if (unpack_trees(ARRAY_SIZE(tree_desc), tree_desc, &unpack_tree_opt))
                die(_("failed to unpack trees"));

        do_diff_cache(&info->b_commit, diff_opt);
}

static int show_stash(int argc, const char **argv, const char *prefix)
{
        int i;
        int ret = -1;
        struct stash_info info = STASH_INFO_INIT;
        struct rev_info rev;
        struct strvec stash_args = STRVEC_INIT;
        struct strvec revision_args = STRVEC_INIT;
        enum {
                UNTRACKED_NONE,
                UNTRACKED_INCLUDE,
                UNTRACKED_ONLY
        } show_untracked = show_include_untracked ? UNTRACKED_INCLUDE : UNTRACKED_NONE;
        struct option options[] = {
                OPT_SET_INT('u', "include-untracked", &show_untracked,
                            N_("include untracked files in the stash"),
                            UNTRACKED_INCLUDE),
                OPT_SET_INT_F(0, "only-untracked", &show_untracked,
                              N_("only show untracked files in the stash"),
                              UNTRACKED_ONLY, PARSE_OPT_NONEG),
                OPT_END()
        };
        int do_usage = 0;

        init_diff_ui_defaults();
        git_config(git_diff_ui_config, NULL);
        init_revisions(&rev, prefix);

        argc = parse_options(argc, argv, prefix, options, git_stash_show_usage,
                             PARSE_OPT_KEEP_ARGV0 | PARSE_OPT_KEEP_UNKNOWN_OPT |
                             PARSE_OPT_KEEP_DASHDASH);

        strvec_push(&revision_args, argv[0]);
        for (i = 1; i < argc; i++) {
                if (argv[i][0] != '-')
                        strvec_push(&stash_args, argv[i]);
                else
                        strvec_push(&revision_args, argv[i]);
        }

        if (get_stash_info(&info, stash_args.nr, stash_args.v))
                goto cleanup;

        /*
         * The config settings are applied only if there are not passed
         * any options.
         */
        if (revision_args.nr == 1) {
                if (show_stat)
                        rev.diffopt.output_format = DIFF_FORMAT_DIFFSTAT;

                if (show_patch)
                        rev.diffopt.output_format |= DIFF_FORMAT_PATCH;

                if (!show_stat && !show_patch) {
                        ret = 0;
                        goto cleanup;
                }
        }

        argc = setup_revisions(revision_args.nr, revision_args.v, &rev, NULL);
        if (argc > 1)
                goto usage;
        if (!rev.diffopt.output_format) {
                rev.diffopt.output_format = DIFF_FORMAT_PATCH;
                diff_setup_done(&rev.diffopt);
        }

        rev.diffopt.flags.recursive = 1;
        setup_diff_pager(&rev.diffopt);
        switch (show_untracked) {
        case UNTRACKED_NONE:
                diff_tree_oid(&info.b_commit, &info.w_commit, "", &rev.diffopt);
                break;
        case UNTRACKED_ONLY:
                if (info.has_u)
                        diff_root_tree_oid(&info.u_tree, "", &rev.diffopt);
                break;
        case UNTRACKED_INCLUDE:
                if (info.has_u)
                        diff_include_untracked(&info, &rev.diffopt);
                else
                        diff_tree_oid(&info.b_commit, &info.w_commit, "", &rev.diffopt);
                break;
        }
        log_tree_diff_flush(&rev);

        ret = diff_result_code(&rev.diffopt, 0);
cleanup:
        strvec_clear(&stash_args);
        free_stash_info(&info);
        release_revisions(&rev);
        if (do_usage)
                usage_with_options(git_stash_show_usage, options);
        return ret;
usage:
        do_usage = 1;
        goto cleanup;
}

static int do_store_stash(const struct object_id *w_commit, const char *stash_msg,
                          int quiet)
{
        if (!stash_msg)
                stash_msg = "Created via \"git stash store\".";

        if (update_ref(stash_msg, ref_stash, w_commit, NULL,
                       REF_FORCE_CREATE_REFLOG,
                       quiet ? UPDATE_REFS_QUIET_ON_ERR :
                       UPDATE_REFS_MSG_ON_ERR)) {
                if (!quiet) {
                        fprintf_ln(stderr, _("Cannot update %s with %s"),
                                   ref_stash, oid_to_hex(w_commit));
                }
                return -1;
        }

        return 0;
}

static int store_stash(int argc, const char **argv, const char *prefix)
{
        int quiet = 0;
        const char *stash_msg = NULL;
        struct object_id obj;
        struct object_context dummy;
        struct option options[] = {
                OPT__QUIET(&quiet, N_("be quiet")),
                OPT_STRING('m', "message", &stash_msg, "message",
                           N_("stash message")),
                OPT_END()
        };

        argc = parse_options(argc, argv, prefix, options,
                             git_stash_store_usage,
                             PARSE_OPT_KEEP_UNKNOWN_OPT);

        if (argc != 1) {
                if (!quiet)
                        fprintf_ln(stderr, _("\"git stash store\" requires one "
                                             "<commit> argument"));
                return -1;
        }

        if (get_oid_with_context(the_repository,
                                 argv[0], quiet ? GET_OID_QUIETLY : 0, &obj,
                                 &dummy)) {
                if (!quiet)
                        fprintf_ln(stderr, _("Cannot update %s with %s"),
                                             ref_stash, argv[0]);
                return -1;
        }

        return do_store_stash(&obj, stash_msg, quiet);
}

static void add_pathspecs(struct strvec *args,
                          const struct pathspec *ps) {
        int i;

        for (i = 0; i < ps->nr; i++)
                strvec_push(args, ps->items[i].original);
}

/*
 * `untracked_files` will be filled with the names of untracked files.
 * The return value is:
 *
 * = 0 if there are not any untracked files
 * > 0 if there are untracked files
 */
static int get_untracked_files(const struct pathspec *ps, int include_untracked,
                               struct strbuf *untracked_files)
{
        int i;
        int found = 0;
        struct dir_struct dir = DIR_INIT;

        if (include_untracked != INCLUDE_ALL_FILES)
                setup_standard_excludes(&dir);

        fill_directory(&dir, the_repository->index, ps);
        for (i = 0; i < dir.nr; i++) {
                struct dir_entry *ent = dir.entries[i];
                found++;
                strbuf_addstr(untracked_files, ent->name);
                /* NUL-terminate: will be fed to update-index -z */
                strbuf_addch(untracked_files, '\0');
        }

        dir_clear(&dir);
        return found;
}

/*
 * The return value of `check_changes_tracked_files()` can be:
 *
 * < 0 if there was an error
 * = 0 if there are no changes.
 * > 0 if there are changes.
 */
static int check_changes_tracked_files(const struct pathspec *ps)
{
        int result;
        struct rev_info rev;
        struct object_id dummy;
        int ret = 0;

        /* No initial commit. */
        if (get_oid("HEAD", &dummy))
                return -1;

        if (read_cache() < 0)
                return -1;

        init_revisions(&rev, NULL);
        copy_pathspec(&rev.prune_data, ps);

        rev.diffopt.flags.quick = 1;
        rev.diffopt.flags.ignore_submodules = 1;
        rev.abbrev = 0;

        add_head_to_pending(&rev);
        diff_setup_done(&rev.diffopt);

        result = run_diff_index(&rev, 1);
        if (diff_result_code(&rev.diffopt, result)) {
                ret = 1;
                goto done;
        }

        result = run_diff_files(&rev, 0);
        if (diff_result_code(&rev.diffopt, result)) {
                ret = 1;
                goto done;
        }

done:
        release_revisions(&rev);
        return ret;
}

/*
 * The function will fill `untracked_files` with the names of untracked files
 * It will return 1 if there were any changes and 0 if there were not.
 */
static int check_changes(const struct pathspec *ps, int include_untracked,
                         struct strbuf *untracked_files)
{
        int ret = 0;
        if (check_changes_tracked_files(ps))
                ret = 1;

        if (include_untracked && get_untracked_files(ps, include_untracked,
                                                     untracked_files))
                ret = 1;

        return ret;
}

static int save_untracked_files(struct stash_info *info, struct strbuf *msg,
                                struct strbuf files)
{
        int ret = 0;
        struct strbuf untracked_msg = STRBUF_INIT;
        struct child_process cp_upd_index = CHILD_PROCESS_INIT;
        struct index_state istate = { NULL };

        cp_upd_index.git_cmd = 1;
        strvec_pushl(&cp_upd_index.args, "update-index", "-z", "--add",
                     "--remove", "--stdin", NULL);
        strvec_pushf(&cp_upd_index.env, "GIT_INDEX_FILE=%s",
                         stash_index_path.buf);

        strbuf_addf(&untracked_msg, "untracked files on %s\n", msg->buf);
        if (pipe_command(&cp_upd_index, files.buf, files.len, NULL, 0,
                         NULL, 0)) {
                ret = -1;
                goto done;
        }

        if (write_index_as_tree(&info->u_tree, &istate, stash_index_path.buf, 0,
                                NULL)) {
                ret = -1;
                goto done;
        }

        if (commit_tree(untracked_msg.buf, untracked_msg.len,
                        &info->u_tree, NULL, &info->u_commit, NULL, NULL)) {
                ret = -1;
                goto done;
        }

done:
        discard_index(&istate);
        strbuf_release(&untracked_msg);
        remove_path(stash_index_path.buf);
        return ret;
}

static int stash_staged(struct stash_info *info, struct strbuf *out_patch,
                        int quiet)
{
        int ret = 0;
        struct child_process cp_diff_tree = CHILD_PROCESS_INIT;
        struct index_state istate = { NULL };

        if (write_index_as_tree(&info->w_tree, &istate, the_repository->index_file,
                                0, NULL)) {
                ret = -1;
                goto done;
        }

        cp_diff_tree.git_cmd = 1;
        strvec_pushl(&cp_diff_tree.args, "diff-tree", "-p", "-U1", "HEAD",
                     oid_to_hex(&info->w_tree), "--", NULL);
        if (pipe_command(&cp_diff_tree, NULL, 0, out_patch, 0, NULL, 0)) {
                ret = -1;
                goto done;
        }

        if (!out_patch->len) {
                if (!quiet)
                        fprintf_ln(stderr, _("No staged changes"));
                ret = 1;
        }

done:
        discard_index(&istate);
        return ret;
}

static int stash_patch(struct stash_info *info, const struct pathspec *ps,
                       struct strbuf *out_patch, int quiet)
{
        int ret = 0;
        struct child_process cp_read_tree = CHILD_PROCESS_INIT;
        struct child_process cp_diff_tree = CHILD_PROCESS_INIT;
        struct index_state istate = { NULL };
        char *old_index_env = NULL, *old_repo_index_file;

        remove_path(stash_index_path.buf);

        cp_read_tree.git_cmd = 1;
        strvec_pushl(&cp_read_tree.args, "read-tree", "HEAD", NULL);
        strvec_pushf(&cp_read_tree.env, "GIT_INDEX_FILE=%s",
                     stash_index_path.buf);
        if (run_command(&cp_read_tree)) {
                ret = -1;
                goto done;
        }

        /* Find out what the user wants. */
        old_repo_index_file = the_repository->index_file;
        the_repository->index_file = stash_index_path.buf;
        old_index_env = xstrdup_or_null(getenv(INDEX_ENVIRONMENT));
        setenv(INDEX_ENVIRONMENT, the_repository->index_file, 1);

        ret = run_add_interactive(NULL, "--patch=stash", ps);

        the_repository->index_file = old_repo_index_file;
        if (old_index_env && *old_index_env)
                setenv(INDEX_ENVIRONMENT, old_index_env, 1);
        else
                unsetenv(INDEX_ENVIRONMENT);
        FREE_AND_NULL(old_index_env);

        /* State of the working tree. */
        if (write_index_as_tree(&info->w_tree, &istate, stash_index_path.buf, 0,
                                NULL)) {
                ret = -1;
                goto done;
        }

        cp_diff_tree.git_cmd = 1;
        strvec_pushl(&cp_diff_tree.args, "diff-tree", "-p", "-U1", "HEAD",
                     oid_to_hex(&info->w_tree), "--", NULL);
        if (pipe_command(&cp_diff_tree, NULL, 0, out_patch, 0, NULL, 0)) {
                ret = -1;
                goto done;
        }

        if (!out_patch->len) {
                if (!quiet)
                        fprintf_ln(stderr, _("No changes selected"));
                ret = 1;
        }

done:
        discard_index(&istate);
        remove_path(stash_index_path.buf);
        return ret;
}

static int stash_working_tree(struct stash_info *info, const struct pathspec *ps)
{
        int ret = 0;
        struct rev_info rev;
        struct child_process cp_upd_index = CHILD_PROCESS_INIT;
        struct strbuf diff_output = STRBUF_INIT;
        struct index_state istate = { NULL };

        init_revisions(&rev, NULL);
        copy_pathspec(&rev.prune_data, ps);

        set_alternate_index_output(stash_index_path.buf);
        if (reset_tree(&info->i_tree, 0, 0)) {
                ret = -1;
                goto done;
        }
        set_alternate_index_output(NULL);

        rev.diffopt.output_format = DIFF_FORMAT_CALLBACK;
        rev.diffopt.format_callback = add_diff_to_buf;
        rev.diffopt.format_callback_data = &diff_output;

        if (read_cache_preload(&rev.diffopt.pathspec) < 0) {
                ret = -1;
                goto done;
        }

        add_pending_object(&rev, parse_object(the_repository, &info->b_commit),
                           "");
        if (run_diff_index(&rev, 0)) {
                ret = -1;
                goto done;
        }

        cp_upd_index.git_cmd = 1;
        strvec_pushl(&cp_upd_index.args, "update-index",
                     "--ignore-skip-worktree-entries",
                     "-z", "--add", "--remove", "--stdin", NULL);
        strvec_pushf(&cp_upd_index.env, "GIT_INDEX_FILE=%s",
                     stash_index_path.buf);

        if (pipe_command(&cp_upd_index, diff_output.buf, diff_output.len,
                         NULL, 0, NULL, 0)) {
                ret = -1;
                goto done;
        }

        if (write_index_as_tree(&info->w_tree, &istate, stash_index_path.buf, 0,
                                NULL)) {
                ret = -1;
                goto done;
        }

done:
        discard_index(&istate);
        release_revisions(&rev);
        strbuf_release(&diff_output);
        remove_path(stash_index_path.buf);
        return ret;
}

static int do_create_stash(const struct pathspec *ps, struct strbuf *stash_msg_buf,
                           int include_untracked, int patch_mode, int only_staged,
                           struct stash_info *info, struct strbuf *patch,
                           int quiet)
{
        int ret = 0;
        int flags = 0;
        int untracked_commit_option = 0;
        const char *head_short_sha1 = NULL;
        const char *branch_ref = NULL;
        const char *branch_name = "(no branch)";
        struct commit *head_commit = NULL;
        struct commit_list *parents = NULL;
        struct strbuf msg = STRBUF_INIT;
        struct strbuf commit_tree_label = STRBUF_INIT;
        struct strbuf untracked_files = STRBUF_INIT;

        prepare_fallback_ident("git stash", "git@stash");

        read_cache_preload(NULL);
        if (refresh_and_write_cache(REFRESH_QUIET, 0, 0) < 0) {
                ret = -1;
                goto done;
        }

        if (get_oid("HEAD", &info->b_commit)) {
                if (!quiet)
                        fprintf_ln(stderr, _("You do not have "
                                             "the initial commit yet"));
                ret = -1;
                goto done;
        } else {
                head_commit = lookup_commit(the_repository, &info->b_commit);
        }

        if (!check_changes(ps, include_untracked, &untracked_files)) {
                ret = 1;
                goto done;
        }

        branch_ref = resolve_ref_unsafe("HEAD", 0, NULL, &flags);
        if (flags & REF_ISSYMREF)
                skip_prefix(branch_ref, "refs/heads/", &branch_name);
        head_short_sha1 = find_unique_abbrev(&head_commit->object.oid,
                                             DEFAULT_ABBREV);
        strbuf_addf(&msg, "%s: %s ", branch_name, head_short_sha1);
        pp_commit_easy(CMIT_FMT_ONELINE, head_commit, &msg);

        strbuf_addf(&commit_tree_label, "index on %s\n", msg.buf);
        commit_list_insert(head_commit, &parents);
        if (write_cache_as_tree(&info->i_tree, 0, NULL) ||
            commit_tree(commit_tree_label.buf, commit_tree_label.len,
                        &info->i_tree, parents, &info->i_commit, NULL, NULL)) {
                if (!quiet)
                        fprintf_ln(stderr, _("Cannot save the current "
                                             "index state"));
                ret = -1;
                goto done;
        }

        if (include_untracked) {
                if (save_untracked_files(info, &msg, untracked_files)) {
                        if (!quiet)
                                fprintf_ln(stderr, _("Cannot save "
                                                     "the untracked files"));
                        ret = -1;
                        goto done;
                }
                untracked_commit_option = 1;
        }
        if (patch_mode) {
                ret = stash_patch(info, ps, patch, quiet);
                if (ret < 0) {
                        if (!quiet)
                                fprintf_ln(stderr, _("Cannot save the current "
                                                     "worktree state"));
                        goto done;
                } else if (ret > 0) {
                        goto done;
                }
        } else if (only_staged) {
                ret = stash_staged(info, patch, quiet);
                if (ret < 0) {
                        if (!quiet)
                                fprintf_ln(stderr, _("Cannot save the current "
                                                     "staged state"));
                        goto done;
                } else if (ret > 0) {
                        goto done;
                }
        } else {
                if (stash_working_tree(info, ps)) {
                        if (!quiet)
                                fprintf_ln(stderr, _("Cannot save the current "
                                                     "worktree state"));
                        ret = -1;
                        goto done;
                }
        }

        if (!stash_msg_buf->len)
                strbuf_addf(stash_msg_buf, "WIP on %s", msg.buf);
        else
                strbuf_insertf(stash_msg_buf, 0, "On %s: ", branch_name);

        /*
         * `parents` will be empty after calling `commit_tree()`, so there is
         * no need to call `free_commit_list()`
         */
        parents = NULL;
        if (untracked_commit_option)
                commit_list_insert(lookup_commit(the_repository,
                                                 &info->u_commit),
                                   &parents);
        commit_list_insert(lookup_commit(the_repository, &info->i_commit),
                           &parents);
        commit_list_insert(head_commit, &parents);

        if (commit_tree(stash_msg_buf->buf, stash_msg_buf->len, &info->w_tree,
                        parents, &info->w_commit, NULL, NULL)) {
                if (!quiet)
                        fprintf_ln(stderr, _("Cannot record "
                                             "working tree state"));
                ret = -1;
                goto done;
        }

done:
        strbuf_release(&commit_tree_label);
        strbuf_release(&msg);
        strbuf_release(&untracked_files);
        return ret;
}

static int create_stash(int argc, const char **argv, const char *prefix)
{
        int ret;
        struct strbuf stash_msg_buf = STRBUF_INIT;
        struct stash_info info = STASH_INFO_INIT;
        struct pathspec ps;

        /* Starting with argv[1], since argv[0] is "create" */
        strbuf_join_argv(&stash_msg_buf, argc - 1, ++argv, ' ');

        memset(&ps, 0, sizeof(ps));
        if (!check_changes_tracked_files(&ps))
                return 0;

        ret = do_create_stash(&ps, &stash_msg_buf, 0, 0, 0, &info,
                              NULL, 0);
        if (!ret)
                printf_ln("%s", oid_to_hex(&info.w_commit));

        free_stash_info(&info);
        strbuf_release(&stash_msg_buf);
        return ret;
}

static int do_push_stash(const struct pathspec *ps, const char *stash_msg, int quiet,
                         int keep_index, int patch_mode, int include_untracked, int only_staged)
{
        int ret = 0;
        struct stash_info info = STASH_INFO_INIT;
        struct strbuf patch = STRBUF_INIT;
        struct strbuf stash_msg_buf = STRBUF_INIT;
        struct strbuf untracked_files = STRBUF_INIT;

        if (patch_mode && keep_index == -1)
                keep_index = 1;

        if (patch_mode && include_untracked) {
                fprintf_ln(stderr, _("Can't use --patch and --include-untracked"
                                     " or --all at the same time"));
                ret = -1;
                goto done;
        }

        /* --patch overrides --staged */
        if (patch_mode)
                only_staged = 0;

        if (only_staged && include_untracked) {
                fprintf_ln(stderr, _("Can't use --staged and --include-untracked"
                                     " or --all at the same time"));
                ret = -1;
                goto done;
        }

        read_cache_preload(NULL);
        if (!include_untracked && ps->nr) {
                int i;
                char *ps_matched = xcalloc(ps->nr, 1);

                /* TODO: audit for interaction with sparse-index. */
                ensure_full_index(&the_index);
                for (i = 0; i < active_nr; i++)
                        ce_path_match(&the_index, active_cache[i], ps,
                                      ps_matched);

                if (report_path_error(ps_matched, ps)) {
                        fprintf_ln(stderr, _("Did you forget to 'git add'?"));
                        ret = -1;
                        free(ps_matched);
                        goto done;
                }
                free(ps_matched);
        }

        if (refresh_and_write_cache(REFRESH_QUIET, 0, 0)) {
                ret = -1;
                goto done;
        }

        if (!check_changes(ps, include_untracked, &untracked_files)) {
                if (!quiet)
                        printf_ln(_("No local changes to save"));
                goto done;
        }

        if (!reflog_exists(ref_stash) && do_clear_stash()) {
                ret = -1;
                if (!quiet)
                        fprintf_ln(stderr, _("Cannot initialize stash"));
                goto done;
        }

        if (stash_msg)
                strbuf_addstr(&stash_msg_buf, stash_msg);
        if (do_create_stash(ps, &stash_msg_buf, include_untracked, patch_mode, only_staged,
                            &info, &patch, quiet)) {
                ret = -1;
                goto done;
        }

        if (do_store_stash(&info.w_commit, stash_msg_buf.buf, 1)) {
                ret = -1;
                if (!quiet)
                        fprintf_ln(stderr, _("Cannot save the current status"));
                goto done;
        }

        if (!quiet)
                printf_ln(_("Saved working directory and index state %s"),
                          stash_msg_buf.buf);

        if (!(patch_mode || only_staged)) {
                if (include_untracked && !ps->nr) {
                        struct child_process cp = CHILD_PROCESS_INIT;

                        cp.git_cmd = 1;
                        if (startup_info->original_cwd) {
                                cp.dir = startup_info->original_cwd;
                                strvec_pushf(&cp.env, "%s=%s",
                                             GIT_WORK_TREE_ENVIRONMENT,
                                             the_repository->worktree);
                        }
                        strvec_pushl(&cp.args, "clean", "--force",
                                     "--quiet", "-d", ":/", NULL);
                        if (include_untracked == INCLUDE_ALL_FILES)
                                strvec_push(&cp.args, "-x");
                        if (run_command(&cp)) {
                                ret = -1;
                                goto done;
                        }
                }
                discard_cache();
                if (ps->nr) {
                        struct child_process cp_add = CHILD_PROCESS_INIT;
                        struct child_process cp_diff = CHILD_PROCESS_INIT;
                        struct child_process cp_apply = CHILD_PROCESS_INIT;
                        struct strbuf out = STRBUF_INIT;

                        cp_add.git_cmd = 1;
                        strvec_push(&cp_add.args, "add");
                        if (!include_untracked)
                                strvec_push(&cp_add.args, "-u");
                        if (include_untracked == INCLUDE_ALL_FILES)
                                strvec_push(&cp_add.args, "--force");
                        strvec_push(&cp_add.args, "--");
                        add_pathspecs(&cp_add.args, ps);
                        if (run_command(&cp_add)) {
                                ret = -1;
                                goto done;
                        }

                        cp_diff.git_cmd = 1;
                        strvec_pushl(&cp_diff.args, "diff-index", "-p",
                                     "--cached", "--binary", "HEAD", "--",
                                     NULL);
                        add_pathspecs(&cp_diff.args, ps);
                        if (pipe_command(&cp_diff, NULL, 0, &out, 0, NULL, 0)) {
                                ret = -1;
                                goto done;
                        }

                        cp_apply.git_cmd = 1;
                        strvec_pushl(&cp_apply.args, "apply", "--index",
                                     "-R", NULL);
                        if (pipe_command(&cp_apply, out.buf, out.len, NULL, 0,
                                         NULL, 0)) {
                                ret = -1;
                                goto done;
                        }
                } else {
                        struct child_process cp = CHILD_PROCESS_INIT;
                        cp.git_cmd = 1;
                        /* BUG: this nukes untracked files in the way */
                        strvec_pushl(&cp.args, "reset", "--hard", "-q",
                                     "--no-recurse-submodules", NULL);
                        if (run_command(&cp)) {
                                ret = -1;
                                goto done;
                        }
                }

                if (keep_index == 1 && !is_null_oid(&info.i_tree)) {
                        struct child_process cp = CHILD_PROCESS_INIT;

                        cp.git_cmd = 1;
                        strvec_pushl(&cp.args, "checkout", "--no-overlay",
                                     oid_to_hex(&info.i_tree), "--", NULL);
                        if (!ps->nr)
                                strvec_push(&cp.args, ":/");
                        else
                                add_pathspecs(&cp.args, ps);
                        if (run_command(&cp)) {
                                ret = -1;
                                goto done;
                        }
                }
                goto done;
        } else {
                struct child_process cp = CHILD_PROCESS_INIT;

                cp.git_cmd = 1;
                strvec_pushl(&cp.args, "apply", "-R", NULL);

                if (pipe_command(&cp, patch.buf, patch.len, NULL, 0, NULL, 0)) {
                        if (!quiet)
                                fprintf_ln(stderr, _("Cannot remove "
                                                     "worktree changes"));
                        ret = -1;
                        goto done;
                }

                if (keep_index < 1) {
                        struct child_process cp = CHILD_PROCESS_INIT;

                        cp.git_cmd = 1;
                        strvec_pushl(&cp.args, "reset", "-q", "--refresh", "--",
                                     NULL);
                        add_pathspecs(&cp.args, ps);
                        if (run_command(&cp)) {
                                ret = -1;
                                goto done;
                        }
                }
                goto done;
        }

done:
        free_stash_info(&info);
        strbuf_release(&stash_msg_buf);
        return ret;
}

static int push_stash(int argc, const char **argv, const char *prefix,
                      int push_assumed)
{
        int force_assume = 0;
        int keep_index = -1;
        int only_staged = 0;
        int patch_mode = 0;
        int include_untracked = 0;
        int quiet = 0;
        int pathspec_file_nul = 0;
        const char *stash_msg = NULL;
        const char *pathspec_from_file = NULL;
        struct pathspec ps;
        struct option options[] = {
                OPT_BOOL('k', "keep-index", &keep_index,
                         N_("keep index")),
                OPT_BOOL('S', "staged", &only_staged,
                         N_("stash staged changes only")),
                OPT_BOOL('p', "patch", &patch_mode,
                         N_("stash in patch mode")),
                OPT__QUIET(&quiet, N_("quiet mode")),
                OPT_BOOL('u', "include-untracked", &include_untracked,
                         N_("include untracked files in stash")),
                OPT_SET_INT('a', "all", &include_untracked,
                            N_("include ignore files"), 2),
                OPT_STRING('m', "message", &stash_msg, N_("message"),
                           N_("stash message")),
                OPT_PATHSPEC_FROM_FILE(&pathspec_from_file),
                OPT_PATHSPEC_FILE_NUL(&pathspec_file_nul),
                OPT_END()
        };

        if (argc) {
                force_assume = !strcmp(argv[0], "-p");
                argc = parse_options(argc, argv, prefix, options,
                                     push_assumed ? git_stash_usage :
                                     git_stash_push_usage,
                                     PARSE_OPT_KEEP_DASHDASH);
        }

        if (argc) {
                if (!strcmp(argv[0], "--")) {
                        argc--;
                        argv++;
                } else if (push_assumed && !force_assume) {
                        die("subcommand wasn't specified; 'push' can't be assumed due to unexpected token '%s'",
                            argv[0]);
                }
        }

        parse_pathspec(&ps, 0, PATHSPEC_PREFER_FULL | PATHSPEC_PREFIX_ORIGIN,
                       prefix, argv);

        if (pathspec_from_file) {
                if (patch_mode)
                        die(_("options '%s' and '%s' cannot be used together"), "--pathspec-from-file", "--patch");

                if (only_staged)
                        die(_("options '%s' and '%s' cannot be used together"), "--pathspec-from-file", "--staged");

                if (ps.nr)
                        die(_("'%s' and pathspec arguments cannot be used together"), "--pathspec-from-file");

                parse_pathspec_file(&ps, 0,
                                    PATHSPEC_PREFER_FULL | PATHSPEC_PREFIX_ORIGIN,
                                    prefix, pathspec_from_file, pathspec_file_nul);
        } else if (pathspec_file_nul) {
                die(_("the option '%s' requires '%s'"), "--pathspec-file-nul", "--pathspec-from-file");
        }

        return do_push_stash(&ps, stash_msg, quiet, keep_index, patch_mode,
                             include_untracked, only_staged);
}

static int push_stash_unassumed(int argc, const char **argv, const char *prefix)
{
        return push_stash(argc, argv, prefix, 0);
}

static int save_stash(int argc, const char **argv, const char *prefix)
{
        int keep_index = -1;
        int only_staged = 0;
        int patch_mode = 0;
        int include_untracked = 0;
        int quiet = 0;
        int ret = 0;
        const char *stash_msg = NULL;
        struct pathspec ps;
        struct strbuf stash_msg_buf = STRBUF_INIT;
        struct option options[] = {
                OPT_BOOL('k', "keep-index", &keep_index,
                         N_("keep index")),
                OPT_BOOL('S', "staged", &only_staged,
                         N_("stash staged changes only")),
                OPT_BOOL('p', "patch", &patch_mode,
                         N_("stash in patch mode")),
                OPT__QUIET(&quiet, N_("quiet mode")),
                OPT_BOOL('u', "include-untracked", &include_untracked,
                         N_("include untracked files in stash")),
                OPT_SET_INT('a', "all", &include_untracked,
                            N_("include ignore files"), 2),
                OPT_STRING('m', "message", &stash_msg, "message",
                           N_("stash message")),
                OPT_END()
        };

        argc = parse_options(argc, argv, prefix, options,
                             git_stash_save_usage,
                             PARSE_OPT_KEEP_DASHDASH);

        if (argc)
                stash_msg = strbuf_join_argv(&stash_msg_buf, argc, argv, ' ');

        memset(&ps, 0, sizeof(ps));
        ret = do_push_stash(&ps, stash_msg, quiet, keep_index,
                            patch_mode, include_untracked, only_staged);

        strbuf_release(&stash_msg_buf);
        return ret;
}

int cmd_stash(int argc, const char **argv, const char *prefix)
{
        pid_t pid = getpid();
        const char *index_file;
        struct strvec args = STRVEC_INIT;
        parse_opt_subcommand_fn *fn = NULL;
        struct option options[] = {
                OPT_SUBCOMMAND("apply", &fn, apply_stash),
                OPT_SUBCOMMAND("clear", &fn, clear_stash),
                OPT_SUBCOMMAND("drop", &fn, drop_stash),
                OPT_SUBCOMMAND("pop", &fn, pop_stash),
                OPT_SUBCOMMAND("branch", &fn, branch_stash),
                OPT_SUBCOMMAND("list", &fn, list_stash),
                OPT_SUBCOMMAND("show", &fn, show_stash),
                OPT_SUBCOMMAND("store", &fn, store_stash),
                OPT_SUBCOMMAND("create", &fn, create_stash),
                OPT_SUBCOMMAND("push", &fn, push_stash_unassumed),
                OPT_SUBCOMMAND_F("save", &fn, save_stash, PARSE_OPT_NOCOMPLETE),
                OPT_END()
        };

        git_config(git_stash_config, NULL);

        argc = parse_options(argc, argv, prefix, options, git_stash_usage,
                             PARSE_OPT_SUBCOMMAND_OPTIONAL |
                             PARSE_OPT_KEEP_UNKNOWN_OPT |
                             PARSE_OPT_KEEP_DASHDASH);

        prepare_repo_settings(the_repository);
        the_repository->settings.command_requires_full_index = 0;

        index_file = get_index_file();
        strbuf_addf(&stash_index_path, "%s.stash.%" PRIuMAX, index_file,
                    (uintmax_t)pid);

        if (fn)
                return !!fn(argc, argv, prefix);
        else if (!argc)
                return !!push_stash_unassumed(0, NULL, prefix);

        /* Assume 'stash push' */
        strvec_push(&args, "push");
        strvec_pushv(&args, argv);
        return !!push_stash(args.nr, args.v, prefix, 1);
}