reset.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
*/
#include "builtin.h"
#include "tag.h"
#include "object.h"
#include "commit.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"
static const char * const git_reset_usage[] = {
"git reset [--mixed | --soft | --hard | --merge | --keep] [-q] [<commit>]",
"git reset [-q] <commit> [--] <paths>...",
"git reset --patch [<commit>] [--] [<paths>...]",
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"), F_OK);
}
static int reset_index_file(const unsigned char *sha1, int reset_type, int quiet)
{
int nr = 1;
int newfd;
struct tree_desc desc[2];
struct unpack_trees_options opts;
struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
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;
if (!quiet)
opts.verbose_update = 1;
switch (reset_type) {
case KEEP:
case MERGE:
opts.update = 1;
break;
case HARD:
opts.update = 1;
/* fallthrough */
default:
opts.reset = 1;
}
newfd = hold_locked_index(lock, 1);
read_cache_unmerged();
if (reset_type == KEEP) {
unsigned char head_sha1[20];
if (get_sha1("HEAD", head_sha1))
return error(_("You do not have a valid HEAD."));
if (!fill_tree_descriptor(desc, head_sha1))
return error(_("Failed to find tree of HEAD."));
nr++;
opts.fn = twoway_merge;
}
if (!fill_tree_descriptor(desc + nr - 1, sha1))
return error(_("Failed to find tree of %s."), sha1_to_hex(sha1));
if (unpack_trees(nr, desc, &opts))
return -1;
if (write_cache(newfd, active_cache, active_nr) ||
commit_locked_index(lock))
return error(_("Could not write new index file."));
return 0;
}
static void print_new_head_line(struct commit *commit)
{
const char *hex, *body;
hex = find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV);
printf(_("HEAD is now at %s"), hex);
body = strstr(commit->buffer, "\n\n");
if (body) {
const char *eol;
size_t len;
body += 2;
eol = strchr(body, '\n');
len = eol ? eol - body : strlen(body);
printf(" %.*s\n", (int) len, body);
}
else
printf("\n");
}
static int update_index_refresh(int fd, struct lock_file *index_lock, int flags)
{
int result;
if (!index_lock) {
index_lock = xcalloc(1, sizeof(struct lock_file));
fd = hold_locked_index(index_lock, 1);
}
if (read_cache() < 0)
return error(_("Could not read index"));
result = refresh_index(&the_index, (flags), NULL, NULL,
_("Unstaged changes after reset:")) ? 1 : 0;
if (write_cache(fd, active_cache, active_nr) ||
commit_locked_index(index_lock))
return error ("Could not refresh index");
return result;
}
static void update_index_from_diff(struct diff_queue_struct *q,
struct diff_options *opt, void *data)
{
int i;
int *discard_flag = data;
/* do_diff_cache() mangled the index */
discard_cache();
*discard_flag = 1;
read_cache();
for (i = 0; i < q->nr; i++) {
struct diff_filespec *one = q->queue[i]->one;
if (one->mode && !is_null_sha1(one->sha1)) {
struct cache_entry *ce;
ce = make_cache_entry(one->mode, one->sha1, one->path,
0, 0);
if (!ce)
die(_("make_cache_entry failed for path '%s'"),
one->path);
add_cache_entry(ce, ADD_CACHE_OK_TO_ADD |
ADD_CACHE_OK_TO_REPLACE);
} else
remove_file_from_cache(one->path);
}
}
static int interactive_reset(const char *revision, const char **argv,
const char *prefix)
{
const char **pathspec = NULL;
if (*argv)
pathspec = get_pathspec(prefix, argv);
return run_add_interactive(revision, "--patch=reset", pathspec);
}
static int read_from_tree(const char *prefix, const char **argv,
unsigned char *tree_sha1, int refresh_flags)
{
struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
int index_fd, index_was_discarded = 0;
struct diff_options opt;
memset(&opt, 0, sizeof(opt));
diff_tree_setup_paths(get_pathspec(prefix, (const char **)argv), &opt);
opt.output_format = DIFF_FORMAT_CALLBACK;
opt.format_callback = update_index_from_diff;
opt.format_callback_data = &index_was_discarded;
index_fd = hold_locked_index(lock, 1);
index_was_discarded = 0;
read_cache();
if (do_diff_cache(tree_sha1, &opt))
return 1;
diffcore_std(&opt);
diff_flush(&opt);
diff_tree_release_paths(&opt);
if (!index_was_discarded)
/* The index is still clobbered from do_diff_cache() */
discard_cache();
return update_index_refresh(index_fd, lock, refresh_flags);
}
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() || read_cache() < 0 || unmerged_cache())
die(_("Cannot do a %s reset in the middle of a merge."),
_(reset_type_names[reset_type]));
}
int cmd_reset(int argc, const char **argv, const char *prefix)
{
int i = 0, reset_type = NONE, update_ref_status = 0, quiet = 0;
int patch_mode = 0;
const char *rev = "HEAD";
unsigned char sha1[20], *orig = NULL, sha1_orig[20],
*old_orig = NULL, sha1_old_orig[20];
struct commit *commit;
struct strbuf msg = STRBUF_INIT;
const struct option options[] = {
OPT__QUIET(&quiet, "be quiet, only report errors"),
OPT_SET_INT(0, "mixed", &reset_type,
"reset HEAD and index", MIXED),
OPT_SET_INT(0, "soft", &reset_type, "reset only HEAD", SOFT),
OPT_SET_INT(0, "hard", &reset_type,
"reset HEAD, index and working tree", HARD),
OPT_SET_INT(0, "merge", &reset_type,
"reset HEAD, index and working tree", MERGE),
OPT_SET_INT(0, "keep", &reset_type,
"reset HEAD but keep local changes", KEEP),
OPT_BOOLEAN('p', "patch", &patch_mode, "select hunks interactively"),
OPT_END()
};
git_config(git_default_config, NULL);
argc = parse_options(argc, argv, prefix, options, git_reset_usage,
PARSE_OPT_KEEP_DASHDASH);
/*
* Possible arguments are:
*
* git reset [-opts] <rev> <paths>...
* git reset [-opts] <rev> -- <paths>...
* git reset [-opts] -- <paths>...
* git reset [-opts] <paths>...
*
* At this point, argv[i] points immediately after [-opts].
*/
if (i < argc) {
if (!strcmp(argv[i], "--")) {
i++; /* reset to HEAD, possibly with paths */
} else if (i + 1 < argc && !strcmp(argv[i+1], "--")) {
rev = argv[i];
i += 2;
}
/*
* Otherwise, argv[i] could be either <rev> or <paths> and
* has to be unambiguous.
*/
else if (!get_sha1(argv[i], sha1)) {
/*
* Ok, argv[i] looks like a rev; it should not
* be a filename.
*/
verify_non_filename(prefix, argv[i]);
rev = argv[i++];
} else {
/* Otherwise we treat this as a filename */
verify_filename(prefix, argv[i]);
}
}
if (get_sha1(rev, sha1))
die(_("Failed to resolve '%s' as a valid ref."), rev);
commit = lookup_commit_reference(sha1);
if (!commit)
die(_("Could not parse object '%s'."), rev);
hashcpy(sha1, commit->object.sha1);
if (patch_mode) {
if (reset_type != NONE)
die(_("--patch is incompatible with --{hard,mixed,soft}"));
return interactive_reset(rev, argv + i, prefix);
}
/* 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 (i < argc) {
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]));
return read_from_tree(prefix, argv + i, sha1,
quiet ? REFRESH_QUIET : REFRESH_IN_PORCELAIN);
}
if (reset_type == NONE)
reset_type = MIXED; /* by default */
if (reset_type != SOFT && reset_type != MIXED)
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]));
/* 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)
die_if_unmerged_cache(reset_type);
else {
int err;
if (reset_type == KEEP)
die_if_unmerged_cache(reset_type);
err = reset_index_file(sha1, reset_type, quiet);
if (reset_type == KEEP)
err = err || reset_index_file(sha1, MIXED, quiet);
if (err)
die(_("Could not reset index file to revision '%s'."), rev);
}
/* Any resets update HEAD to the head being switched to,
* saving the previous head in ORIG_HEAD before. */
if (!get_sha1("ORIG_HEAD", sha1_old_orig))
old_orig = sha1_old_orig;
if (!get_sha1("HEAD", sha1_orig)) {
orig = sha1_orig;
set_reflog_message(&msg, "updating ORIG_HEAD", NULL);
update_ref(msg.buf, "ORIG_HEAD", orig, old_orig, 0, MSG_ON_ERR);
}
else if (old_orig)
delete_ref("ORIG_HEAD", old_orig, 0);
set_reflog_message(&msg, "updating HEAD", rev);
update_ref_status = update_ref(msg.buf, "HEAD", sha1, orig, 0, MSG_ON_ERR);
switch (reset_type) {
case HARD:
if (!update_ref_status && !quiet)
print_new_head_line(commit);
break;
case SOFT: /* Nothing else to do. */
break;
case MIXED: /* Report what has not been updated. */
update_index_refresh(0, NULL,
quiet ? REFRESH_QUIET : REFRESH_IN_PORCELAIN);
break;
}
remove_branch_state();
strbuf_release(&msg);
return update_ref_status;
}