git/builtin/checkout.c
Junio C Hamano b3e83cc752 hold_locked_index(): align error handling with hold_lockfile_for_update()
Callers of the hold_locked_index() function pass 0 when they want to
prepare to write a new version of the index file without wishing to
die or emit an error message when the request fails (e.g. somebody
else already held the lock), and pass 1 when they want the call to
die upon failure.

This option is called LOCK_DIE_ON_ERROR by the underlying lockfile
API, and the hold_locked_index() function translates the paramter to
LOCK_DIE_ON_ERROR when calling the hold_lock_file_for_update().

Replace these hardcoded '1' with LOCK_DIE_ON_ERROR and stop
translating.  Callers other than the ones that are replaced with
this change pass '0' to the function; no behaviour change is
intended with this patch.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
---

Among the callers of hold_locked_index() that passes 0:

 - diff.c::refresh_index_quietly() at the end of "git diff" is an
   opportunistic update; it leaks the lockfile structure but it is
   just before the program exits and nobody should care.

 - builtin/describe.c::cmd_describe(),
   builtin/commit.c::cmd_status(),
   sequencer.c::read_and_refresh_cache() are all opportunistic
   updates and they are OK.

 - builtin/update-index.c::cmd_update_index() takes a lock upfront
   but we may end up not needing to update the index (i.e. the
   entries may be fully up-to-date), in which case we do not need to
   issue an error upon failure to acquire the lock.  We do diagnose
   and die if we indeed need to update, so it is OK.

 - wt-status.c::require_clean_work_tree() IS BUGGY.  It asks
   silence, does not check the returned value.  Compare with
   callsites like cmd_describe() and cmd_status() to notice that it
   is wrong to call update_index_if_able() unconditionally.
2016-12-07 11:31:59 -08:00

1288 lines
36 KiB
C

#include "builtin.h"
#include "lockfile.h"
#include "parse-options.h"
#include "refs.h"
#include "commit.h"
#include "tree.h"
#include "tree-walk.h"
#include "cache-tree.h"
#include "unpack-trees.h"
#include "dir.h"
#include "run-command.h"
#include "merge-recursive.h"
#include "branch.h"
#include "diff.h"
#include "revision.h"
#include "remote.h"
#include "blob.h"
#include "xdiff-interface.h"
#include "ll-merge.h"
#include "resolve-undo.h"
#include "submodule-config.h"
#include "submodule.h"
static const char * const checkout_usage[] = {
N_("git checkout [<options>] <branch>"),
N_("git checkout [<options>] [<branch>] -- <file>..."),
NULL,
};
struct checkout_opts {
int patch_mode;
int quiet;
int merge;
int force;
int force_detach;
int writeout_stage;
int overwrite_ignore;
int ignore_skipworktree;
int ignore_other_worktrees;
int show_progress;
const char *new_branch;
const char *new_branch_force;
const char *new_orphan_branch;
int new_branch_log;
enum branch_track track;
struct diff_options diff_options;
int branch_exists;
const char *prefix;
struct pathspec pathspec;
struct tree *source_tree;
};
static int post_checkout_hook(struct commit *old, struct commit *new,
int changed)
{
return run_hook_le(NULL, "post-checkout",
sha1_to_hex(old ? old->object.oid.hash : null_sha1),
sha1_to_hex(new ? new->object.oid.hash : null_sha1),
changed ? "1" : "0", NULL);
/* "new" can be NULL when checking out from the index before
a commit exists. */
}
static int update_some(const unsigned char *sha1, struct strbuf *base,
const char *pathname, unsigned mode, int stage, void *context)
{
int len;
struct cache_entry *ce;
int pos;
if (S_ISDIR(mode))
return READ_TREE_RECURSIVE;
len = base->len + strlen(pathname);
ce = xcalloc(1, cache_entry_size(len));
hashcpy(ce->oid.hash, sha1);
memcpy(ce->name, base->buf, base->len);
memcpy(ce->name + base->len, pathname, len - base->len);
ce->ce_flags = create_ce_flags(0) | CE_UPDATE;
ce->ce_namelen = len;
ce->ce_mode = create_ce_mode(mode);
/*
* If the entry is the same as the current index, we can leave the old
* entry in place. Whether it is UPTODATE or not, checkout_entry will
* do the right thing.
*/
pos = cache_name_pos(ce->name, ce->ce_namelen);
if (pos >= 0) {
struct cache_entry *old = active_cache[pos];
if (ce->ce_mode == old->ce_mode &&
!oidcmp(&ce->oid, &old->oid)) {
old->ce_flags |= CE_UPDATE;
free(ce);
return 0;
}
}
add_cache_entry(ce, ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE);
return 0;
}
static int read_tree_some(struct tree *tree, const struct pathspec *pathspec)
{
read_tree_recursive(tree, "", 0, 0, pathspec, update_some, NULL);
/* update the index with the given tree's info
* for all args, expanding wildcards, and exit
* with any non-zero return code.
*/
return 0;
}
static int skip_same_name(const struct cache_entry *ce, int pos)
{
while (++pos < active_nr &&
!strcmp(active_cache[pos]->name, ce->name))
; /* skip */
return pos;
}
static int check_stage(int stage, const struct cache_entry *ce, int pos)
{
while (pos < active_nr &&
!strcmp(active_cache[pos]->name, ce->name)) {
if (ce_stage(active_cache[pos]) == stage)
return 0;
pos++;
}
if (stage == 2)
return error(_("path '%s' does not have our version"), ce->name);
else
return error(_("path '%s' does not have their version"), ce->name);
}
static int check_stages(unsigned stages, const struct cache_entry *ce, int pos)
{
unsigned seen = 0;
const char *name = ce->name;
while (pos < active_nr) {
ce = active_cache[pos];
if (strcmp(name, ce->name))
break;
seen |= (1 << ce_stage(ce));
pos++;
}
if ((stages & seen) != stages)
return error(_("path '%s' does not have all necessary versions"),
name);
return 0;
}
static int checkout_stage(int stage, const struct cache_entry *ce, int pos,
const struct checkout *state)
{
while (pos < active_nr &&
!strcmp(active_cache[pos]->name, ce->name)) {
if (ce_stage(active_cache[pos]) == stage)
return checkout_entry(active_cache[pos], state, NULL);
pos++;
}
if (stage == 2)
return error(_("path '%s' does not have our version"), ce->name);
else
return error(_("path '%s' does not have their version"), ce->name);
}
static int checkout_merged(int pos, const struct checkout *state)
{
struct cache_entry *ce = active_cache[pos];
const char *path = ce->name;
mmfile_t ancestor, ours, theirs;
int status;
struct object_id oid;
mmbuffer_t result_buf;
struct object_id threeway[3];
unsigned mode = 0;
memset(threeway, 0, sizeof(threeway));
while (pos < active_nr) {
int stage;
stage = ce_stage(ce);
if (!stage || strcmp(path, ce->name))
break;
oidcpy(&threeway[stage - 1], &ce->oid);
if (stage == 2)
mode = create_ce_mode(ce->ce_mode);
pos++;
ce = active_cache[pos];
}
if (is_null_oid(&threeway[1]) || is_null_oid(&threeway[2]))
return error(_("path '%s' does not have necessary versions"), path);
read_mmblob(&ancestor, &threeway[0]);
read_mmblob(&ours, &threeway[1]);
read_mmblob(&theirs, &threeway[2]);
/*
* NEEDSWORK: re-create conflicts from merges with
* merge.renormalize set, too
*/
status = ll_merge(&result_buf, path, &ancestor, "base",
&ours, "ours", &theirs, "theirs", NULL);
free(ancestor.ptr);
free(ours.ptr);
free(theirs.ptr);
if (status < 0 || !result_buf.ptr) {
free(result_buf.ptr);
return error(_("path '%s': cannot merge"), path);
}
/*
* NEEDSWORK:
* There is absolutely no reason to write this as a blob object
* and create a phony cache entry just to leak. This hack is
* primarily to get to the write_entry() machinery that massages
* the contents to work-tree format and writes out which only
* allows it for a cache entry. The code in write_entry() needs
* to be refactored to allow us to feed a <buffer, size, mode>
* instead of a cache entry. Such a refactoring would help
* merge_recursive as well (it also writes the merge result to the
* object database even when it may contain conflicts).
*/
if (write_sha1_file(result_buf.ptr, result_buf.size,
blob_type, oid.hash))
die(_("Unable to add merge result for '%s'"), path);
ce = make_cache_entry(mode, oid.hash, path, 2, 0);
if (!ce)
die(_("make_cache_entry failed for path '%s'"), path);
status = checkout_entry(ce, state, NULL);
return status;
}
static int checkout_paths(const struct checkout_opts *opts,
const char *revision)
{
int pos;
struct checkout state = CHECKOUT_INIT;
static char *ps_matched;
struct object_id rev;
struct commit *head;
int errs = 0;
struct lock_file *lock_file;
if (opts->track != BRANCH_TRACK_UNSPECIFIED)
die(_("'%s' cannot be used with updating paths"), "--track");
if (opts->new_branch_log)
die(_("'%s' cannot be used with updating paths"), "-l");
if (opts->force && opts->patch_mode)
die(_("'%s' cannot be used with updating paths"), "-f");
if (opts->force_detach)
die(_("'%s' cannot be used with updating paths"), "--detach");
if (opts->merge && opts->patch_mode)
die(_("'%s' cannot be used with %s"), "--merge", "--patch");
if (opts->force && opts->merge)
die(_("'%s' cannot be used with %s"), "-f", "-m");
if (opts->new_branch)
die(_("Cannot update paths and switch to branch '%s' at the same time."),
opts->new_branch);
if (opts->patch_mode)
return run_add_interactive(revision, "--patch=checkout",
&opts->pathspec);
lock_file = xcalloc(1, sizeof(struct lock_file));
hold_locked_index(lock_file, LOCK_DIE_ON_ERROR);
if (read_cache_preload(&opts->pathspec) < 0)
return error(_("index file corrupt"));
if (opts->source_tree)
read_tree_some(opts->source_tree, &opts->pathspec);
ps_matched = xcalloc(opts->pathspec.nr, 1);
/*
* Make sure all pathspecs participated in locating the paths
* to be checked out.
*/
for (pos = 0; pos < active_nr; pos++) {
struct cache_entry *ce = active_cache[pos];
ce->ce_flags &= ~CE_MATCHED;
if (!opts->ignore_skipworktree && ce_skip_worktree(ce))
continue;
if (opts->source_tree && !(ce->ce_flags & CE_UPDATE))
/*
* "git checkout tree-ish -- path", but this entry
* is in the original index; it will not be checked
* out to the working tree and it does not matter
* if pathspec matched this entry. We will not do
* anything to this entry at all.
*/
continue;
/*
* Either this entry came from the tree-ish we are
* checking the paths out of, or we are checking out
* of the index.
*
* If it comes from the tree-ish, we already know it
* matches the pathspec and could just stamp
* CE_MATCHED to it from update_some(). But we still
* need ps_matched and read_tree_recursive (and
* eventually tree_entry_interesting) cannot fill
* ps_matched yet. Once it can, we can avoid calling
* match_pathspec() for _all_ entries when
* opts->source_tree != NULL.
*/
if (ce_path_match(ce, &opts->pathspec, ps_matched))
ce->ce_flags |= CE_MATCHED;
}
if (report_path_error(ps_matched, &opts->pathspec, opts->prefix)) {
free(ps_matched);
return 1;
}
free(ps_matched);
/* "checkout -m path" to recreate conflicted state */
if (opts->merge)
unmerge_marked_index(&the_index);
/* Any unmerged paths? */
for (pos = 0; pos < active_nr; pos++) {
const struct cache_entry *ce = active_cache[pos];
if (ce->ce_flags & CE_MATCHED) {
if (!ce_stage(ce))
continue;
if (opts->force) {
warning(_("path '%s' is unmerged"), ce->name);
} else if (opts->writeout_stage) {
errs |= check_stage(opts->writeout_stage, ce, pos);
} else if (opts->merge) {
errs |= check_stages((1<<2) | (1<<3), ce, pos);
} else {
errs = 1;
error(_("path '%s' is unmerged"), ce->name);
}
pos = skip_same_name(ce, pos) - 1;
}
}
if (errs)
return 1;
/* Now we are committed to check them out */
state.force = 1;
state.refresh_cache = 1;
state.istate = &the_index;
for (pos = 0; pos < active_nr; pos++) {
struct cache_entry *ce = active_cache[pos];
if (ce->ce_flags & CE_MATCHED) {
if (!ce_stage(ce)) {
errs |= checkout_entry(ce, &state, NULL);
continue;
}
if (opts->writeout_stage)
errs |= checkout_stage(opts->writeout_stage, ce, pos, &state);
else if (opts->merge)
errs |= checkout_merged(pos, &state);
pos = skip_same_name(ce, pos) - 1;
}
}
if (write_locked_index(&the_index, lock_file, COMMIT_LOCK))
die(_("unable to write new index file"));
read_ref_full("HEAD", 0, rev.hash, NULL);
head = lookup_commit_reference_gently(rev.hash, 1);
errs |= post_checkout_hook(head, head, 0);
return errs;
}
static void show_local_changes(struct object *head,
const struct diff_options *opts)
{
struct rev_info rev;
/* I think we want full paths, even if we're in a subdirectory. */
init_revisions(&rev, NULL);
rev.diffopt.flags = opts->flags;
rev.diffopt.output_format |= DIFF_FORMAT_NAME_STATUS;
diff_setup_done(&rev.diffopt);
add_pending_object(&rev, head, NULL);
run_diff_index(&rev, 0);
}
static void describe_detached_head(const char *msg, struct commit *commit)
{
struct strbuf sb = STRBUF_INIT;
if (!parse_commit(commit))
pp_commit_easy(CMIT_FMT_ONELINE, commit, &sb);
fprintf(stderr, "%s %s... %s\n", msg,
find_unique_abbrev(commit->object.oid.hash, DEFAULT_ABBREV), sb.buf);
strbuf_release(&sb);
}
static int reset_tree(struct tree *tree, const struct checkout_opts *o,
int worktree, int *writeout_error)
{
struct unpack_trees_options opts;
struct tree_desc tree_desc;
memset(&opts, 0, sizeof(opts));
opts.head_idx = -1;
opts.update = worktree;
opts.skip_unmerged = !worktree;
opts.reset = 1;
opts.merge = 1;
opts.fn = oneway_merge;
opts.verbose_update = o->show_progress;
opts.src_index = &the_index;
opts.dst_index = &the_index;
parse_tree(tree);
init_tree_desc(&tree_desc, tree->buffer, tree->size);
switch (unpack_trees(1, &tree_desc, &opts)) {
case -2:
*writeout_error = 1;
/*
* We return 0 nevertheless, as the index is all right
* and more importantly we have made best efforts to
* update paths in the work tree, and we cannot revert
* them.
*/
case 0:
return 0;
default:
return 128;
}
}
struct branch_info {
const char *name; /* The short name used */
const char *path; /* The full name of a real branch */
struct commit *commit; /* The named commit */
/*
* if not null the branch is detached because it's already
* checked out in this checkout
*/
char *checkout;
};
static void setup_branch_path(struct branch_info *branch)
{
struct strbuf buf = STRBUF_INIT;
strbuf_branchname(&buf, branch->name);
if (strcmp(buf.buf, branch->name))
branch->name = xstrdup(buf.buf);
strbuf_splice(&buf, 0, 0, "refs/heads/", 11);
branch->path = strbuf_detach(&buf, NULL);
}
static int merge_working_tree(const struct checkout_opts *opts,
struct branch_info *old,
struct branch_info *new,
int *writeout_error)
{
int ret;
struct lock_file *lock_file = xcalloc(1, sizeof(struct lock_file));
hold_locked_index(lock_file, LOCK_DIE_ON_ERROR);
if (read_cache_preload(NULL) < 0)
return error(_("index file corrupt"));
resolve_undo_clear();
if (opts->force) {
ret = reset_tree(new->commit->tree, opts, 1, writeout_error);
if (ret)
return ret;
} else {
struct tree_desc trees[2];
struct tree *tree;
struct unpack_trees_options topts;
memset(&topts, 0, sizeof(topts));
topts.head_idx = -1;
topts.src_index = &the_index;
topts.dst_index = &the_index;
setup_unpack_trees_porcelain(&topts, "checkout");
refresh_cache(REFRESH_QUIET);
if (unmerged_cache()) {
error(_("you need to resolve your current index first"));
return 1;
}
/* 2-way merge to the new branch */
topts.initial_checkout = is_cache_unborn();
topts.update = 1;
topts.merge = 1;
topts.gently = opts->merge && old->commit;
topts.verbose_update = opts->show_progress;
topts.fn = twoway_merge;
if (opts->overwrite_ignore) {
topts.dir = xcalloc(1, sizeof(*topts.dir));
topts.dir->flags |= DIR_SHOW_IGNORED;
setup_standard_excludes(topts.dir);
}
tree = parse_tree_indirect(old->commit ?
old->commit->object.oid.hash :
EMPTY_TREE_SHA1_BIN);
init_tree_desc(&trees[0], tree->buffer, tree->size);
tree = parse_tree_indirect(new->commit->object.oid.hash);
init_tree_desc(&trees[1], tree->buffer, tree->size);
ret = unpack_trees(2, trees, &topts);
if (ret == -1) {
/*
* Unpack couldn't do a trivial merge; either
* give up or do a real merge, depending on
* whether the merge flag was used.
*/
struct tree *result;
struct tree *work;
struct merge_options o;
if (!opts->merge)
return 1;
/*
* Without old->commit, the below is the same as
* the two-tree unpack we already tried and failed.
*/
if (!old->commit)
return 1;
/* Do more real merge */
/*
* We update the index fully, then write the
* tree from the index, then merge the new
* branch with the current tree, with the old
* branch as the base. Then we reset the index
* (but not the working tree) to the new
* branch, leaving the working tree as the
* merged version, but skipping unmerged
* entries in the index.
*/
add_files_to_cache(NULL, NULL, 0);
/*
* NEEDSWORK: carrying over local changes
* when branches have different end-of-line
* normalization (or clean+smudge rules) is
* a pain; plumb in an option to set
* o.renormalize?
*/
init_merge_options(&o);
o.verbosity = 0;
work = write_tree_from_memory(&o);
ret = reset_tree(new->commit->tree, opts, 1,
writeout_error);
if (ret)
return ret;
o.ancestor = old->name;
o.branch1 = new->name;
o.branch2 = "local";
ret = merge_trees(&o, new->commit->tree, work,
old->commit->tree, &result);
if (ret < 0)
exit(128);
ret = reset_tree(new->commit->tree, opts, 0,
writeout_error);
strbuf_release(&o.obuf);
if (ret)
return ret;
}
}
if (!active_cache_tree)
active_cache_tree = cache_tree();
if (!cache_tree_fully_valid(active_cache_tree))
cache_tree_update(&the_index, WRITE_TREE_SILENT | WRITE_TREE_REPAIR);
if (write_locked_index(&the_index, lock_file, COMMIT_LOCK))
die(_("unable to write new index file"));
if (!opts->force && !opts->quiet)
show_local_changes(&new->commit->object, &opts->diff_options);
return 0;
}
static void report_tracking(struct branch_info *new)
{
struct strbuf sb = STRBUF_INIT;
struct branch *branch = branch_get(new->name);
if (!format_tracking_info(branch, &sb))
return;
fputs(sb.buf, stdout);
strbuf_release(&sb);
}
static void update_refs_for_switch(const struct checkout_opts *opts,
struct branch_info *old,
struct branch_info *new)
{
struct strbuf msg = STRBUF_INIT;
const char *old_desc, *reflog_msg;
if (opts->new_branch) {
if (opts->new_orphan_branch) {
if (opts->new_branch_log && !log_all_ref_updates) {
int ret;
char *refname;
struct strbuf err = STRBUF_INIT;
refname = mkpathdup("refs/heads/%s", opts->new_orphan_branch);
ret = safe_create_reflog(refname, 1, &err);
free(refname);
if (ret) {
fprintf(stderr, _("Can not do reflog for '%s': %s\n"),
opts->new_orphan_branch, err.buf);
strbuf_release(&err);
return;
}
strbuf_release(&err);
}
}
else
create_branch(opts->new_branch, new->name,
opts->new_branch_force ? 1 : 0,
opts->new_branch_log,
opts->new_branch_force ? 1 : 0,
opts->quiet,
opts->track);
new->name = opts->new_branch;
setup_branch_path(new);
}
old_desc = old->name;
if (!old_desc && old->commit)
old_desc = oid_to_hex(&old->commit->object.oid);
reflog_msg = getenv("GIT_REFLOG_ACTION");
if (!reflog_msg)
strbuf_addf(&msg, "checkout: moving from %s to %s",
old_desc ? old_desc : "(invalid)", new->name);
else
strbuf_insert(&msg, 0, reflog_msg, strlen(reflog_msg));
if (!strcmp(new->name, "HEAD") && !new->path && !opts->force_detach) {
/* Nothing to do. */
} else if (opts->force_detach || !new->path) { /* No longer on any branch. */
update_ref(msg.buf, "HEAD", new->commit->object.oid.hash, NULL,
REF_NODEREF, UPDATE_REFS_DIE_ON_ERR);
if (!opts->quiet) {
if (old->path &&
advice_detached_head && !opts->force_detach)
detach_advice(new->name);
describe_detached_head(_("HEAD is now at"), new->commit);
}
} else if (new->path) { /* Switch branches. */
if (create_symref("HEAD", new->path, msg.buf) < 0)
die(_("unable to update HEAD"));
if (!opts->quiet) {
if (old->path && !strcmp(new->path, old->path)) {
if (opts->new_branch_force)
fprintf(stderr, _("Reset branch '%s'\n"),
new->name);
else
fprintf(stderr, _("Already on '%s'\n"),
new->name);
} else if (opts->new_branch) {
if (opts->branch_exists)
fprintf(stderr, _("Switched to and reset branch '%s'\n"), new->name);
else
fprintf(stderr, _("Switched to a new branch '%s'\n"), new->name);
} else {
fprintf(stderr, _("Switched to branch '%s'\n"),
new->name);
}
}
if (old->path && old->name) {
if (!ref_exists(old->path) && reflog_exists(old->path))
delete_reflog(old->path);
}
}
remove_branch_state();
strbuf_release(&msg);
if (!opts->quiet &&
(new->path || (!opts->force_detach && !strcmp(new->name, "HEAD"))))
report_tracking(new);
}
static int add_pending_uninteresting_ref(const char *refname,
const struct object_id *oid,
int flags, void *cb_data)
{
add_pending_sha1(cb_data, refname, oid->hash, UNINTERESTING);
return 0;
}
static void describe_one_orphan(struct strbuf *sb, struct commit *commit)
{
strbuf_addstr(sb, " ");
strbuf_add_unique_abbrev(sb, commit->object.oid.hash, DEFAULT_ABBREV);
strbuf_addch(sb, ' ');
if (!parse_commit(commit))
pp_commit_easy(CMIT_FMT_ONELINE, commit, sb);
strbuf_addch(sb, '\n');
}
#define ORPHAN_CUTOFF 4
static void suggest_reattach(struct commit *commit, struct rev_info *revs)
{
struct commit *c, *last = NULL;
struct strbuf sb = STRBUF_INIT;
int lost = 0;
while ((c = get_revision(revs)) != NULL) {
if (lost < ORPHAN_CUTOFF)
describe_one_orphan(&sb, c);
last = c;
lost++;
}
if (ORPHAN_CUTOFF < lost) {
int more = lost - ORPHAN_CUTOFF;
if (more == 1)
describe_one_orphan(&sb, last);
else
strbuf_addf(&sb, _(" ... and %d more.\n"), more);
}
fprintf(stderr,
Q_(
/* The singular version */
"Warning: you are leaving %d commit behind, "
"not connected to\n"
"any of your branches:\n\n"
"%s\n",
/* The plural version */
"Warning: you are leaving %d commits behind, "
"not connected to\n"
"any of your branches:\n\n"
"%s\n",
/* Give ngettext() the count */
lost),
lost,
sb.buf);
strbuf_release(&sb);
if (advice_detached_head)
fprintf(stderr,
Q_(
/* The singular version */
"If you want to keep it by creating a new branch, "
"this may be a good time\nto do so with:\n\n"
" git branch <new-branch-name> %s\n\n",
/* The plural version */
"If you want to keep them by creating a new branch, "
"this may be a good time\nto do so with:\n\n"
" git branch <new-branch-name> %s\n\n",
/* Give ngettext() the count */
lost),
find_unique_abbrev(commit->object.oid.hash, DEFAULT_ABBREV));
}
/*
* We are about to leave commit that was at the tip of a detached
* HEAD. If it is not reachable from any ref, this is the last chance
* for the user to do so without resorting to reflog.
*/
static void orphaned_commit_warning(struct commit *old, struct commit *new)
{
struct rev_info revs;
struct object *object = &old->object;
struct object_array refs;
init_revisions(&revs, NULL);
setup_revisions(0, NULL, &revs, NULL);
object->flags &= ~UNINTERESTING;
add_pending_object(&revs, object, oid_to_hex(&object->oid));
for_each_ref(add_pending_uninteresting_ref, &revs);
add_pending_sha1(&revs, "HEAD", new->object.oid.hash, UNINTERESTING);
refs = revs.pending;
revs.leak_pending = 1;
if (prepare_revision_walk(&revs))
die(_("internal error in revision walk"));
if (!(old->object.flags & UNINTERESTING))
suggest_reattach(old, &revs);
else
describe_detached_head(_("Previous HEAD position was"), old);
clear_commit_marks_for_object_array(&refs, ALL_REV_FLAGS);
free(refs.objects);
}
static int switch_branches(const struct checkout_opts *opts,
struct branch_info *new)
{
int ret = 0;
struct branch_info old;
void *path_to_free;
struct object_id rev;
int flag, writeout_error = 0;
memset(&old, 0, sizeof(old));
old.path = path_to_free = resolve_refdup("HEAD", 0, rev.hash, &flag);
old.commit = lookup_commit_reference_gently(rev.hash, 1);
if (!(flag & REF_ISSYMREF))
old.path = NULL;
if (old.path)
skip_prefix(old.path, "refs/heads/", &old.name);
if (!new->name) {
new->name = "HEAD";
new->commit = old.commit;
if (!new->commit)
die(_("You are on a branch yet to be born"));
parse_commit_or_die(new->commit);
}
ret = merge_working_tree(opts, &old, new, &writeout_error);
if (ret) {
free(path_to_free);
return ret;
}
if (!opts->quiet && !old.path && old.commit && new->commit != old.commit)
orphaned_commit_warning(old.commit, new->commit);
update_refs_for_switch(opts, &old, new);
ret = post_checkout_hook(old.commit, new->commit, 1);
free(path_to_free);
return ret || writeout_error;
}
static int git_checkout_config(const char *var, const char *value, void *cb)
{
if (!strcmp(var, "diff.ignoresubmodules")) {
struct checkout_opts *opts = cb;
handle_ignore_submodules_arg(&opts->diff_options, value);
return 0;
}
if (starts_with(var, "submodule."))
return parse_submodule_config_option(var, value);
return git_xmerge_config(var, value, NULL);
}
struct tracking_name_data {
/* const */ char *src_ref;
char *dst_ref;
struct object_id *dst_oid;
int unique;
};
static int check_tracking_name(struct remote *remote, void *cb_data)
{
struct tracking_name_data *cb = cb_data;
struct refspec query;
memset(&query, 0, sizeof(struct refspec));
query.src = cb->src_ref;
if (remote_find_tracking(remote, &query) ||
get_oid(query.dst, cb->dst_oid)) {
free(query.dst);
return 0;
}
if (cb->dst_ref) {
free(query.dst);
cb->unique = 0;
return 0;
}
cb->dst_ref = query.dst;
return 0;
}
static const char *unique_tracking_name(const char *name, struct object_id *oid)
{
struct tracking_name_data cb_data = { NULL, NULL, NULL, 1 };
char src_ref[PATH_MAX];
snprintf(src_ref, PATH_MAX, "refs/heads/%s", name);
cb_data.src_ref = src_ref;
cb_data.dst_oid = oid;
for_each_remote(check_tracking_name, &cb_data);
if (cb_data.unique)
return cb_data.dst_ref;
free(cb_data.dst_ref);
return NULL;
}
static int parse_branchname_arg(int argc, const char **argv,
int dwim_new_local_branch_ok,
struct branch_info *new,
struct checkout_opts *opts,
struct object_id *rev)
{
struct tree **source_tree = &opts->source_tree;
const char **new_branch = &opts->new_branch;
int argcount = 0;
struct object_id branch_rev;
const char *arg;
int dash_dash_pos;
int has_dash_dash = 0;
int i;
/*
* case 1: git checkout <ref> -- [<paths>]
*
* <ref> must be a valid tree, everything after the '--' must be
* a path.
*
* case 2: git checkout -- [<paths>]
*
* everything after the '--' must be paths.
*
* case 3: git checkout <something> [--]
*
* (a) If <something> is a commit, that is to
* switch to the branch or detach HEAD at it. As a special case,
* if <something> is A...B (missing A or B means HEAD but you can
* omit at most one side), and if there is a unique merge base
* between A and B, A...B names that merge base.
*
* (b) If <something> is _not_ a commit, either "--" is present
* or <something> is not a path, no -t or -b was given, and
* and there is a tracking branch whose name is <something>
* in one and only one remote, then this is a short-hand to
* fork local <something> from that remote-tracking branch.
*
* (c) Otherwise, if "--" is present, treat it like case (1).
*
* (d) Otherwise :
* - if it's a reference, treat it like case (1)
* - else if it's a path, treat it like case (2)
* - else: fail.
*
* case 4: git checkout <something> <paths>
*
* The first argument must not be ambiguous.
* - If it's *only* a reference, treat it like case (1).
* - If it's only a path, treat it like case (2).
* - else: fail.
*
*/
if (!argc)
return 0;
arg = argv[0];
dash_dash_pos = -1;
for (i = 0; i < argc; i++) {
if (!strcmp(argv[i], "--")) {
dash_dash_pos = i;
break;
}
}
if (dash_dash_pos == 0)
return 1; /* case (2) */
else if (dash_dash_pos == 1)
has_dash_dash = 1; /* case (3) or (1) */
else if (dash_dash_pos >= 2)
die(_("only one reference expected, %d given."), dash_dash_pos);
if (!strcmp(arg, "-"))
arg = "@{-1}";
if (get_oid_mb(arg, rev)) {
/*
* Either case (3) or (4), with <something> not being
* a commit, or an attempt to use case (1) with an
* invalid ref.
*
* It's likely an error, but we need to find out if
* we should auto-create the branch, case (3).(b).
*/
int recover_with_dwim = dwim_new_local_branch_ok;
if (!has_dash_dash &&
(check_filename(opts->prefix, arg) || !no_wildcard(arg)))
recover_with_dwim = 0;
/*
* Accept "git checkout foo" and "git checkout foo --"
* as candidates for dwim.
*/
if (!(argc == 1 && !has_dash_dash) &&
!(argc == 2 && has_dash_dash))
recover_with_dwim = 0;
if (recover_with_dwim) {
const char *remote = unique_tracking_name(arg, rev);
if (remote) {
*new_branch = arg;
arg = remote;
/* DWIMmed to create local branch, case (3).(b) */
} else {
recover_with_dwim = 0;
}
}
if (!recover_with_dwim) {
if (has_dash_dash)
die(_("invalid reference: %s"), arg);
return argcount;
}
}
/* we can't end up being in (2) anymore, eat the argument */
argcount++;
argv++;
argc--;
new->name = arg;
setup_branch_path(new);
if (!check_refname_format(new->path, 0) &&
!read_ref(new->path, branch_rev.hash))
oidcpy(rev, &branch_rev);
else
new->path = NULL; /* not an existing branch */
new->commit = lookup_commit_reference_gently(rev->hash, 1);
if (!new->commit) {
/* not a commit */
*source_tree = parse_tree_indirect(rev->hash);
} else {
parse_commit_or_die(new->commit);
*source_tree = new->commit->tree;
}
if (!*source_tree) /* case (1): want a tree */
die(_("reference is not a tree: %s"), arg);
if (!has_dash_dash) { /* case (3).(d) -> (1) */
/*
* Do not complain the most common case
* git checkout branch
* even if there happen to be a file called 'branch';
* it would be extremely annoying.
*/
if (argc)
verify_non_filename(opts->prefix, arg);
} else {
argcount++;
argv++;
argc--;
}
return argcount;
}
static int switch_unborn_to_new_branch(const struct checkout_opts *opts)
{
int status;
struct strbuf branch_ref = STRBUF_INIT;
if (!opts->new_branch)
die(_("You are on a branch yet to be born"));
strbuf_addf(&branch_ref, "refs/heads/%s", opts->new_branch);
status = create_symref("HEAD", branch_ref.buf, "checkout -b");
strbuf_release(&branch_ref);
if (!opts->quiet)
fprintf(stderr, _("Switched to a new branch '%s'\n"),
opts->new_branch);
return status;
}
static int checkout_branch(struct checkout_opts *opts,
struct branch_info *new)
{
if (opts->pathspec.nr)
die(_("paths cannot be used with switching branches"));
if (opts->patch_mode)
die(_("'%s' cannot be used with switching branches"),
"--patch");
if (opts->writeout_stage)
die(_("'%s' cannot be used with switching branches"),
"--ours/--theirs");
if (opts->force && opts->merge)
die(_("'%s' cannot be used with '%s'"), "-f", "-m");
if (opts->force_detach && opts->new_branch)
die(_("'%s' cannot be used with '%s'"),
"--detach", "-b/-B/--orphan");
if (opts->new_orphan_branch) {
if (opts->track != BRANCH_TRACK_UNSPECIFIED)
die(_("'%s' cannot be used with '%s'"), "--orphan", "-t");
} else if (opts->force_detach) {
if (opts->track != BRANCH_TRACK_UNSPECIFIED)
die(_("'%s' cannot be used with '%s'"), "--detach", "-t");
} else if (opts->track == BRANCH_TRACK_UNSPECIFIED)
opts->track = git_branch_track;
if (new->name && !new->commit)
die(_("Cannot switch branch to a non-commit '%s'"),
new->name);
if (new->path && !opts->force_detach && !opts->new_branch &&
!opts->ignore_other_worktrees) {
struct object_id oid;
int flag;
char *head_ref = resolve_refdup("HEAD", 0, oid.hash, &flag);
if (head_ref &&
(!(flag & REF_ISSYMREF) || strcmp(head_ref, new->path)))
die_if_checked_out(new->path, 1);
free(head_ref);
}
if (!new->commit && opts->new_branch) {
struct object_id rev;
int flag;
if (!read_ref_full("HEAD", 0, rev.hash, &flag) &&
(flag & REF_ISSYMREF) && is_null_oid(&rev))
return switch_unborn_to_new_branch(opts);
}
return switch_branches(opts, new);
}
int cmd_checkout(int argc, const char **argv, const char *prefix)
{
struct checkout_opts opts;
struct branch_info new;
char *conflict_style = NULL;
int dwim_new_local_branch = 1;
struct option options[] = {
OPT__QUIET(&opts.quiet, N_("suppress progress reporting")),
OPT_STRING('b', NULL, &opts.new_branch, N_("branch"),
N_("create and checkout a new branch")),
OPT_STRING('B', NULL, &opts.new_branch_force, N_("branch"),
N_("create/reset and checkout a branch")),
OPT_BOOL('l', NULL, &opts.new_branch_log, N_("create reflog for new branch")),
OPT_BOOL(0, "detach", &opts.force_detach, N_("detach HEAD at named commit")),
OPT_SET_INT('t', "track", &opts.track, N_("set upstream info for new branch"),
BRANCH_TRACK_EXPLICIT),
OPT_STRING(0, "orphan", &opts.new_orphan_branch, N_("new-branch"), N_("new unparented branch")),
OPT_SET_INT('2', "ours", &opts.writeout_stage, N_("checkout our version for unmerged files"),
2),
OPT_SET_INT('3', "theirs", &opts.writeout_stage, N_("checkout their version for unmerged files"),
3),
OPT__FORCE(&opts.force, N_("force checkout (throw away local modifications)")),
OPT_BOOL('m', "merge", &opts.merge, N_("perform a 3-way merge with the new branch")),
OPT_BOOL(0, "overwrite-ignore", &opts.overwrite_ignore, N_("update ignored files (default)")),
OPT_STRING(0, "conflict", &conflict_style, N_("style"),
N_("conflict style (merge or diff3)")),
OPT_BOOL('p', "patch", &opts.patch_mode, N_("select hunks interactively")),
OPT_BOOL(0, "ignore-skip-worktree-bits", &opts.ignore_skipworktree,
N_("do not limit pathspecs to sparse entries only")),
OPT_HIDDEN_BOOL(0, "guess", &dwim_new_local_branch,
N_("second guess 'git checkout <no-such-branch>'")),
OPT_BOOL(0, "ignore-other-worktrees", &opts.ignore_other_worktrees,
N_("do not check if another worktree is holding the given ref")),
OPT_BOOL(0, "progress", &opts.show_progress, N_("force progress reporting")),
OPT_END(),
};
memset(&opts, 0, sizeof(opts));
memset(&new, 0, sizeof(new));
opts.overwrite_ignore = 1;
opts.prefix = prefix;
opts.show_progress = -1;
gitmodules_config();
git_config(git_checkout_config, &opts);
opts.track = BRANCH_TRACK_UNSPECIFIED;
argc = parse_options(argc, argv, prefix, options, checkout_usage,
PARSE_OPT_KEEP_DASHDASH);
if (opts.show_progress < 0) {
if (opts.quiet)
opts.show_progress = 0;
else
opts.show_progress = isatty(2);
}
if (conflict_style) {
opts.merge = 1; /* implied */
git_xmerge_config("merge.conflictstyle", conflict_style, NULL);
}
if ((!!opts.new_branch + !!opts.new_branch_force + !!opts.new_orphan_branch) > 1)
die(_("-b, -B and --orphan are mutually exclusive"));
/*
* From here on, new_branch will contain the branch to be checked out,
* and new_branch_force and new_orphan_branch will tell us which one of
* -b/-B/--orphan is being used.
*/
if (opts.new_branch_force)
opts.new_branch = opts.new_branch_force;
if (opts.new_orphan_branch)
opts.new_branch = opts.new_orphan_branch;
/* --track without -b/-B/--orphan should DWIM */
if (opts.track != BRANCH_TRACK_UNSPECIFIED && !opts.new_branch) {
const char *argv0 = argv[0];
if (!argc || !strcmp(argv0, "--"))
die (_("--track needs a branch name"));
skip_prefix(argv0, "refs/", &argv0);
skip_prefix(argv0, "remotes/", &argv0);
argv0 = strchr(argv0, '/');
if (!argv0 || !argv0[1])
die (_("Missing branch name; try -b"));
opts.new_branch = argv0 + 1;
}
/*
* Extract branch name from command line arguments, so
* all that is left is pathspecs.
*
* Handle
*
* 1) git checkout <tree> -- [<paths>]
* 2) git checkout -- [<paths>]
* 3) git checkout <something> [<paths>]
*
* including "last branch" syntax and DWIM-ery for names of
* remote branches, erroring out for invalid or ambiguous cases.
*/
if (argc) {
struct object_id rev;
int dwim_ok =
!opts.patch_mode &&
dwim_new_local_branch &&
opts.track == BRANCH_TRACK_UNSPECIFIED &&
!opts.new_branch;
int n = parse_branchname_arg(argc, argv, dwim_ok,
&new, &opts, &rev);
argv += n;
argc -= n;
}
if (argc) {
parse_pathspec(&opts.pathspec, 0,
opts.patch_mode ? PATHSPEC_PREFIX_ORIGIN : 0,
prefix, argv);
if (!opts.pathspec.nr)
die(_("invalid path specification"));
/*
* Try to give more helpful suggestion.
* new_branch && argc > 1 will be caught later.
*/
if (opts.new_branch && argc == 1)
die(_("Cannot update paths and switch to branch '%s' at the same time.\n"
"Did you intend to checkout '%s' which can not be resolved as commit?"),
opts.new_branch, argv[0]);
if (opts.force_detach)
die(_("git checkout: --detach does not take a path argument '%s'"),
argv[0]);
if (1 < !!opts.writeout_stage + !!opts.force + !!opts.merge)
die(_("git checkout: --ours/--theirs, --force and --merge are incompatible when\n"
"checking out of the index."));
}
if (opts.new_branch) {
struct strbuf buf = STRBUF_INIT;
opts.branch_exists =
validate_new_branchname(opts.new_branch, &buf,
!!opts.new_branch_force,
!!opts.new_branch_force);
strbuf_release(&buf);
}
if (opts.patch_mode || opts.pathspec.nr)
return checkout_paths(&opts, new.name);
else
return checkout_branch(&opts, &new);
}