git/builtin/reset.c
Elijah Newren 480d3d6bf9 Change unpack_trees' 'reset' flag into an enum
Traditionally, unpack_trees_options->reset was used to signal that it
was okay to delete any untracked files in the way.  This was used by
`git read-tree --reset`, but then started appearing in other places as
well.  However, many of the other uses should not be deleting untracked
files in the way.  Change this value to an enum so that a value of 1
(i.e. "true") can be split into two:
   UNPACK_RESET_PROTECT_UNTRACKED,
   UNPACK_RESET_OVERWRITE_UNTRACKED
In order to catch accidental misuses (i.e. where folks call it the way
they traditionally used to), define the special enum value of
   UNPACK_RESET_INVALID = 1
which will trigger a BUG().

Modify existing callers so that
   read-tree --reset
   reset --hard
   checkout --force
continue using the UNPACK_RESET_OVERWRITE_UNTRACKED logic, while other
callers, including
   am
   checkout without --force
   stash  (though currently dead code; reset always had a value of 0)
   numerous callers from rebase/sequencer to reset_head()
will use the new UNPACK_RESET_PROTECT_UNTRACKED value.

Also, note that it has been reported that 'git checkout <treeish>
<pathspec>' currently also allows overwriting untracked files[1].  That
case should also be fixed, but it does not use unpack_trees() and thus
is outside the scope of the current changes.

[1] https://lore.kernel.org/git/15dad590-087e-5a48-9238-5d2826950506@gmail.com/

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-27 13:38:37 -07:00

460 lines
13 KiB
C

/*
* "git reset" builtin command
*
* Copyright (c) 2007 Carlos Rica
*
* Based on git-reset.sh, which is
*
* Copyright (c) 2005, 2006 Linus Torvalds and Junio C Hamano
*/
#define USE_THE_INDEX_COMPATIBILITY_MACROS
#include "builtin.h"
#include "config.h"
#include "lockfile.h"
#include "tag.h"
#include "object.h"
#include "pretty.h"
#include "run-command.h"
#include "refs.h"
#include "diff.h"
#include "diffcore.h"
#include "tree.h"
#include "branch.h"
#include "parse-options.h"
#include "unpack-trees.h"
#include "cache-tree.h"
#include "submodule.h"
#include "submodule-config.h"
#define REFRESH_INDEX_DELAY_WARNING_IN_MS (2 * 1000)
static const char * const git_reset_usage[] = {
N_("git reset [--mixed | --soft | --hard | --merge | --keep] [-q] [<commit>]"),
N_("git reset [-q] [<tree-ish>] [--] <pathspec>..."),
N_("git reset [-q] [--pathspec-from-file [--pathspec-file-nul]] [<tree-ish>]"),
N_("git reset --patch [<tree-ish>] [--] [<pathspec>...]"),
NULL
};
enum reset_type { MIXED, SOFT, HARD, MERGE, KEEP, NONE };
static const char *reset_type_names[] = {
N_("mixed"), N_("soft"), N_("hard"), N_("merge"), N_("keep"), NULL
};
static inline int is_merge(void)
{
return !access(git_path_merge_head(the_repository), F_OK);
}
static int reset_index(const char *ref, const struct object_id *oid, int reset_type, int quiet)
{
int i, nr = 0;
struct tree_desc desc[2];
struct tree *tree;
struct unpack_trees_options opts;
int ret = -1;
memset(&opts, 0, sizeof(opts));
opts.head_idx = 1;
opts.src_index = &the_index;
opts.dst_index = &the_index;
opts.fn = oneway_merge;
opts.merge = 1;
init_checkout_metadata(&opts.meta, ref, oid, NULL);
if (!quiet)
opts.verbose_update = 1;
switch (reset_type) {
case KEEP:
case MERGE:
opts.update = 1;
opts.preserve_ignored = 0; /* FIXME: !overwrite_ignore */
break;
case HARD:
opts.update = 1;
opts.reset = UNPACK_RESET_OVERWRITE_UNTRACKED;
break;
case MIXED:
opts.reset = UNPACK_RESET_PROTECT_UNTRACKED;
/* but opts.update=0, so working tree not updated */
break;
default:
BUG("invalid reset_type passed to reset_index");
}
read_cache_unmerged();
if (reset_type == KEEP) {
struct object_id head_oid;
if (get_oid("HEAD", &head_oid))
return error(_("You do not have a valid HEAD."));
if (!fill_tree_descriptor(the_repository, desc + nr, &head_oid))
return error(_("Failed to find tree of HEAD."));
nr++;
opts.fn = twoway_merge;
}
if (!fill_tree_descriptor(the_repository, desc + nr, oid)) {
error(_("Failed to find tree of %s."), oid_to_hex(oid));
goto out;
}
nr++;
if (unpack_trees(nr, desc, &opts))
goto out;
if (reset_type == MIXED || reset_type == HARD) {
tree = parse_tree_indirect(oid);
prime_cache_tree(the_repository, the_repository->index, tree);
}
ret = 0;
out:
for (i = 0; i < nr; i++)
free((void *)desc[i].buffer);
return ret;
}
static void print_new_head_line(struct commit *commit)
{
struct strbuf buf = STRBUF_INIT;
printf(_("HEAD is now at %s"),
find_unique_abbrev(&commit->object.oid, DEFAULT_ABBREV));
pp_commit_easy(CMIT_FMT_ONELINE, commit, &buf);
if (buf.len > 0)
printf(" %s", buf.buf);
putchar('\n');
strbuf_release(&buf);
}
static void update_index_from_diff(struct diff_queue_struct *q,
struct diff_options *opt, void *data)
{
int i;
int intent_to_add = *(int *)data;
for (i = 0; i < q->nr; i++) {
struct diff_filespec *one = q->queue[i]->one;
int is_missing = !(one->mode && !is_null_oid(&one->oid));
struct cache_entry *ce;
if (is_missing && !intent_to_add) {
remove_file_from_cache(one->path);
continue;
}
ce = make_cache_entry(&the_index, one->mode, &one->oid, one->path,
0, 0);
if (!ce)
die(_("make_cache_entry failed for path '%s'"),
one->path);
if (is_missing) {
ce->ce_flags |= CE_INTENT_TO_ADD;
set_object_name_for_intent_to_add_entry(ce);
}
add_cache_entry(ce, ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE);
}
}
static int read_from_tree(const struct pathspec *pathspec,
struct object_id *tree_oid,
int intent_to_add)
{
struct diff_options opt;
memset(&opt, 0, sizeof(opt));
copy_pathspec(&opt.pathspec, pathspec);
opt.output_format = DIFF_FORMAT_CALLBACK;
opt.format_callback = update_index_from_diff;
opt.format_callback_data = &intent_to_add;
opt.flags.override_submodule_config = 1;
opt.repo = the_repository;
if (do_diff_cache(tree_oid, &opt))
return 1;
diffcore_std(&opt);
diff_flush(&opt);
clear_pathspec(&opt.pathspec);
return 0;
}
static void set_reflog_message(struct strbuf *sb, const char *action,
const char *rev)
{
const char *rla = getenv("GIT_REFLOG_ACTION");
strbuf_reset(sb);
if (rla)
strbuf_addf(sb, "%s: %s", rla, action);
else if (rev)
strbuf_addf(sb, "reset: moving to %s", rev);
else
strbuf_addf(sb, "reset: %s", action);
}
static void die_if_unmerged_cache(int reset_type)
{
if (is_merge() || unmerged_cache())
die(_("Cannot do a %s reset in the middle of a merge."),
_(reset_type_names[reset_type]));
}
static void parse_args(struct pathspec *pathspec,
const char **argv, const char *prefix,
int patch_mode,
const char **rev_ret)
{
const char *rev = "HEAD";
struct object_id unused;
/*
* Possible arguments are:
*
* git reset [-opts] [<rev>]
* git reset [-opts] <tree> [<paths>...]
* git reset [-opts] <tree> -- [<paths>...]
* git reset [-opts] -- [<paths>...]
* git reset [-opts] <paths>...
*
* At this point, argv points immediately after [-opts].
*/
if (argv[0]) {
if (!strcmp(argv[0], "--")) {
argv++; /* reset to HEAD, possibly with paths */
} else if (argv[1] && !strcmp(argv[1], "--")) {
rev = argv[0];
argv += 2;
}
/*
* Otherwise, argv[0] could be either <rev> or <paths> and
* has to be unambiguous. If there is a single argument, it
* can not be a tree
*/
else if ((!argv[1] && !get_oid_committish(argv[0], &unused)) ||
(argv[1] && !get_oid_treeish(argv[0], &unused))) {
/*
* Ok, argv[0] looks like a commit/tree; it should not
* be a filename.
*/
verify_non_filename(prefix, argv[0]);
rev = *argv++;
} else {
/* Otherwise we treat this as a filename */
verify_filename(prefix, argv[0], 1);
}
}
*rev_ret = rev;
if (read_cache() < 0)
die(_("index file corrupt"));
parse_pathspec(pathspec, 0,
PATHSPEC_PREFER_FULL |
(patch_mode ? PATHSPEC_PREFIX_ORIGIN : 0),
prefix, argv);
}
static int reset_refs(const char *rev, const struct object_id *oid)
{
int update_ref_status;
struct strbuf msg = STRBUF_INIT;
struct object_id *orig = NULL, oid_orig,
*old_orig = NULL, oid_old_orig;
if (!get_oid("ORIG_HEAD", &oid_old_orig))
old_orig = &oid_old_orig;
if (!get_oid("HEAD", &oid_orig)) {
orig = &oid_orig;
set_reflog_message(&msg, "updating ORIG_HEAD", NULL);
update_ref(msg.buf, "ORIG_HEAD", orig, old_orig, 0,
UPDATE_REFS_MSG_ON_ERR);
} else if (old_orig)
delete_ref(NULL, "ORIG_HEAD", old_orig, 0);
set_reflog_message(&msg, "updating HEAD", rev);
update_ref_status = update_ref(msg.buf, "HEAD", oid, orig, 0,
UPDATE_REFS_MSG_ON_ERR);
strbuf_release(&msg);
return update_ref_status;
}
static int git_reset_config(const char *var, const char *value, void *cb)
{
if (!strcmp(var, "submodule.recurse"))
return git_default_submodule_config(var, value, cb);
return git_default_config(var, value, cb);
}
int cmd_reset(int argc, const char **argv, const char *prefix)
{
int reset_type = NONE, update_ref_status = 0, quiet = 0;
int patch_mode = 0, pathspec_file_nul = 0, unborn;
const char *rev, *pathspec_from_file = NULL;
struct object_id oid;
struct pathspec pathspec;
int intent_to_add = 0;
const struct option options[] = {
OPT__QUIET(&quiet, N_("be quiet, only report errors")),
OPT_SET_INT(0, "mixed", &reset_type,
N_("reset HEAD and index"), MIXED),
OPT_SET_INT(0, "soft", &reset_type, N_("reset only HEAD"), SOFT),
OPT_SET_INT(0, "hard", &reset_type,
N_("reset HEAD, index and working tree"), HARD),
OPT_SET_INT(0, "merge", &reset_type,
N_("reset HEAD, index and working tree"), MERGE),
OPT_SET_INT(0, "keep", &reset_type,
N_("reset HEAD but keep local changes"), KEEP),
OPT_CALLBACK_F(0, "recurse-submodules", NULL,
"reset", "control recursive updating of submodules",
PARSE_OPT_OPTARG, option_parse_recurse_submodules_worktree_updater),
OPT_BOOL('p', "patch", &patch_mode, N_("select hunks interactively")),
OPT_BOOL('N', "intent-to-add", &intent_to_add,
N_("record only the fact that removed paths will be added later")),
OPT_PATHSPEC_FROM_FILE(&pathspec_from_file),
OPT_PATHSPEC_FILE_NUL(&pathspec_file_nul),
OPT_END()
};
git_config(git_reset_config, NULL);
git_config_get_bool("reset.quiet", &quiet);
argc = parse_options(argc, argv, prefix, options, git_reset_usage,
PARSE_OPT_KEEP_DASHDASH);
parse_args(&pathspec, argv, prefix, patch_mode, &rev);
if (pathspec_from_file) {
if (patch_mode)
die(_("--pathspec-from-file is incompatible with --patch"));
if (pathspec.nr)
die(_("--pathspec-from-file is incompatible with pathspec arguments"));
parse_pathspec_file(&pathspec, 0,
PATHSPEC_PREFER_FULL,
prefix, pathspec_from_file, pathspec_file_nul);
} else if (pathspec_file_nul) {
die(_("--pathspec-file-nul requires --pathspec-from-file"));
}
unborn = !strcmp(rev, "HEAD") && get_oid("HEAD", &oid);
if (unborn) {
/* reset on unborn branch: treat as reset to empty tree */
oidcpy(&oid, the_hash_algo->empty_tree);
} else if (!pathspec.nr && !patch_mode) {
struct commit *commit;
if (get_oid_committish(rev, &oid))
die(_("Failed to resolve '%s' as a valid revision."), rev);
commit = lookup_commit_reference(the_repository, &oid);
if (!commit)
die(_("Could not parse object '%s'."), rev);
oidcpy(&oid, &commit->object.oid);
} else {
struct tree *tree;
if (get_oid_treeish(rev, &oid))
die(_("Failed to resolve '%s' as a valid tree."), rev);
tree = parse_tree_indirect(&oid);
if (!tree)
die(_("Could not parse object '%s'."), rev);
oidcpy(&oid, &tree->object.oid);
}
if (patch_mode) {
if (reset_type != NONE)
die(_("--patch is incompatible with --{hard,mixed,soft}"));
trace2_cmd_mode("patch-interactive");
return run_add_interactive(rev, "--patch=reset", &pathspec);
}
/* git reset tree [--] paths... can be used to
* load chosen paths from the tree into the index without
* affecting the working tree nor HEAD. */
if (pathspec.nr) {
if (reset_type == MIXED)
warning(_("--mixed with paths is deprecated; use 'git reset -- <paths>' instead."));
else if (reset_type != NONE)
die(_("Cannot do %s reset with paths."),
_(reset_type_names[reset_type]));
}
if (reset_type == NONE)
reset_type = MIXED; /* by default */
if (pathspec.nr)
trace2_cmd_mode("path");
else
trace2_cmd_mode(reset_type_names[reset_type]);
if (reset_type != SOFT && (reset_type != MIXED || get_git_work_tree()))
setup_work_tree();
if (reset_type == MIXED && is_bare_repository())
die(_("%s reset is not allowed in a bare repository"),
_(reset_type_names[reset_type]));
if (intent_to_add && reset_type != MIXED)
die(_("-N can only be used with --mixed"));
/* Soft reset does not touch the index file nor the working tree
* at all, but requires them in a good order. Other resets reset
* the index file to the tree object we are switching to. */
if (reset_type == SOFT || reset_type == KEEP)
die_if_unmerged_cache(reset_type);
if (reset_type != SOFT) {
struct lock_file lock = LOCK_INIT;
hold_locked_index(&lock, LOCK_DIE_ON_ERROR);
if (reset_type == MIXED) {
int flags = quiet ? REFRESH_QUIET : REFRESH_IN_PORCELAIN;
if (read_from_tree(&pathspec, &oid, intent_to_add))
return 1;
the_index.updated_skipworktree = 1;
if (!quiet && get_git_work_tree()) {
uint64_t t_begin, t_delta_in_ms;
t_begin = getnanotime();
refresh_index(&the_index, flags, NULL, NULL,
_("Unstaged changes after reset:"));
t_delta_in_ms = (getnanotime() - t_begin) / 1000000;
if (advice_enabled(ADVICE_RESET_QUIET_WARNING) && t_delta_in_ms > REFRESH_INDEX_DELAY_WARNING_IN_MS) {
printf(_("\nIt took %.2f seconds to enumerate unstaged changes after reset. You can\n"
"use '--quiet' to avoid this. Set the config setting reset.quiet to true\n"
"to make this the default.\n"), t_delta_in_ms / 1000.0);
}
}
} else {
struct object_id dummy;
char *ref = NULL;
int err;
dwim_ref(rev, strlen(rev), &dummy, &ref, 0);
if (ref && !starts_with(ref, "refs/"))
FREE_AND_NULL(ref);
err = reset_index(ref, &oid, reset_type, quiet);
if (reset_type == KEEP && !err)
err = reset_index(ref, &oid, MIXED, quiet);
if (err)
die(_("Could not reset index file to revision '%s'."), rev);
free(ref);
}
if (write_locked_index(&the_index, &lock, COMMIT_LOCK))
die(_("Could not write new index file."));
}
if (!pathspec.nr && !unborn) {
/* Any resets without paths update HEAD to the head being
* switched to, saving the previous head in ORIG_HEAD before. */
update_ref_status = reset_refs(rev, &oid);
if (reset_type == HARD && !update_ref_status && !quiet)
print_new_head_line(lookup_commit_reference(the_repository, &oid));
}
if (!pathspec.nr)
remove_branch_state(the_repository, 0);
return update_ref_status;
}