struct tree *write_tree_from_memory(struct merge_options *o)
{
struct tree *result = NULL;
if (unmerged_cache()) {
int i;
output(o, 0, "There are unmerged index entries:");
for (i = 0; i < active_nr; i++) {
struct cache_entry *ce = active_cache[i];
if (ce_stage(ce))
output(o, 0, "%d %.*s", ce_stage(ce), ce_namelen(ce), ce->name);
}
return NULL;
}
if (!active_cache_tree)
active_cache_tree = cache_tree();
if (!cache_tree_fully_valid(active_cache_tree) &&
cache_tree_update(active_cache_tree,
active_cache, active_nr, 0, 0) < 0)
die("error building trees");
result = lookup_tree(active_cache_tree->sha1);
return result;
}
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]));
}
struct tree *write_tree_from_memory(struct merge_options *o)
{
struct tree *result = NULL;
if (unmerged_cache()) {
int i;
fprintf(stderr, "BUG: There are unmerged index entries:\n");
for (i = 0; i < active_nr; i++) {
struct cache_entry *ce = active_cache[i];
if (ce_stage(ce))
fprintf(stderr, "BUG: %d %.*s", ce_stage(ce),
(int)ce_namelen(ce), ce->name);
}
die("Bug in merge-recursive.c");
}
if (!active_cache_tree)
active_cache_tree = cache_tree();
if (!cache_tree_fully_valid(active_cache_tree) &&
cache_tree_update(active_cache_tree,
active_cache, active_nr, 0, 0) < 0)
die("error building trees");
result = lookup_tree(active_cache_tree->sha1);
return result;
}
int merge_trees(struct merge_options *o,
struct tree *head,
struct tree *merge,
struct tree *common,
struct tree **result)
{
int code, clean;
if (o->subtree_merge) {
merge = shift_tree_object(head, merge);
common = shift_tree_object(head, common);
}
if (sha_eq(common->object.sha1, merge->object.sha1)) {
output(o, 0, "Already uptodate!");
*result = head;
return 1;
}
code = git_merge_trees(o->call_depth, common, head, merge);
if (code != 0)
die("merging of trees %s and %s failed",
sha1_to_hex(head->object.sha1),
sha1_to_hex(merge->object.sha1));
if (unmerged_cache()) {
struct string_list *entries, *re_head, *re_merge;
int i;
string_list_clear(&o->current_file_set, 1);
string_list_clear(&o->current_directory_set, 1);
get_files_dirs(o, head);
get_files_dirs(o, merge);
entries = get_unmerged();
re_head = get_renames(o, head, common, head, merge, entries);
re_merge = get_renames(o, merge, common, head, merge, entries);
clean = process_renames(o, re_head, re_merge);
for (i = 0; i < entries->nr; i++) {
const char *path = entries->items[i].string;
struct stage_data *e = entries->items[i].util;
if (!e->processed
&& !process_entry(o, path, e))
clean = 0;
}
string_list_clear(re_merge, 0);
string_list_clear(re_head, 0);
string_list_clear(entries, 1);
}
else
clean = 1;
if (o->call_depth)
*result = write_tree_from_memory(o);
return clean;
}
int cmd_reset(int argc, const char **argv, const char *prefix)
{
int i = 0, reset_type = NONE, update_ref_status = 0, quiet = 0;
const char *rev = "HEAD";
unsigned char sha1[20], *orig = NULL, sha1_orig[20],
*old_orig = NULL, sha1_old_orig[20];
struct commit *commit;
char *reflog_action, msg[1024];
const struct option options[] = {
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_BOOLEAN('q', NULL, &quiet,
"disable showing new HEAD in hard reset and progress message"),
OPT_END()
};
git_config(git_default_config, NULL);
argc = parse_options(argc, argv, options, git_reset_usage,
PARSE_OPT_KEEP_DASHDASH);
reflog_action = args_to_str(argv);
setenv("GIT_REFLOG_ACTION", reflog_action, 0);
/*
* 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 unambigous.
*/
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);
/* 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 option is deprecated with paths.");
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_SAY_CHANGED);
}
if (reset_type == NONE)
reset_type = MIXED; /* by default */
if (reset_type == HARD && is_bare_repository())
die("hard reset makes no sense in a bare repository");
/* 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) {
if (is_merge() || read_cache() < 0 || unmerged_cache())
die("Cannot do a soft reset in the middle of a merge.");
}
else if (reset_index_file(sha1, (reset_type == HARD), quiet))
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;
prepend_reflog_action("updating ORIG_HEAD", msg, sizeof(msg));
update_ref(msg, "ORIG_HEAD", orig, old_orig, 0, MSG_ON_ERR);
}
else if (old_orig)
delete_ref("ORIG_HEAD", old_orig);
prepend_reflog_action("updating HEAD", msg, sizeof(msg));
update_ref_status = update_ref(msg, "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_SAY_CHANGED);
break;
}
remove_branch_state();
free(reflog_action);
return update_ref_status;
}
static int merge_working_tree(const struct checkout_opts *opts,
struct branch_info *old_branch_info,
struct branch_info *new_branch_info,
int *writeout_error)
{
int ret;
struct lock_file lock_file = LOCK_INIT;
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(get_commit_tree(new_branch_info->commit),
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_branch_info->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_branch_info->commit ?
&old_branch_info->commit->object.oid :
the_hash_algo->empty_tree);
init_tree_desc(&trees[0], tree->buffer, tree->size);
tree = parse_tree_indirect(&new_branch_info->commit->object.oid);
init_tree_desc(&trees[1], tree->buffer, tree->size);
ret = unpack_trees(2, trees, &topts);
clear_unpack_trees_porcelain(&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_branch_info->commit, the below is the same as
* the two-tree unpack we already tried and failed.
*/
if (!old_branch_info->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, the_repository);
o.verbosity = 0;
work = write_tree_from_memory(&o);
ret = reset_tree(get_commit_tree(new_branch_info->commit),
opts, 1,
writeout_error);
if (ret)
return ret;
o.ancestor = old_branch_info->name;
o.branch1 = new_branch_info->name;
o.branch2 = "local";
ret = merge_trees(&o,
get_commit_tree(new_branch_info->commit),
work,
get_commit_tree(old_branch_info->commit),
&result);
if (ret < 0)
exit(128);
ret = reset_tree(get_commit_tree(new_branch_info->commit),
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_branch_info->commit->object, &opts->diff_options);
return 0;
}
int cmd_merge(int argc, const char **argv, const char *prefix)
{
unsigned char result_tree[20];
struct strbuf buf;
const char *head_arg;
int flag, head_invalid = 0, i;
int best_cnt = -1, merge_was_ok = 0, automerge_was_ok = 0;
struct commit_list *common = NULL;
const char *best_strategy = NULL, *wt_strategy = NULL;
struct commit_list **remotes = &remoteheads;
setup_work_tree();
if (unmerged_cache())
die("You are in the middle of a conflicted merge.");
/*
* Check if we are _not_ on a detached HEAD, i.e. if there is a
* current branch.
*/
branch = resolve_ref("HEAD", head, 0, &flag);
if (branch && !prefixcmp(branch, "refs/heads/"))
branch += 11;
if (is_null_sha1(head))
head_invalid = 1;
git_config(git_merge_config, NULL);
/* for color.ui */
if (diff_use_color_default == -1)
diff_use_color_default = git_use_color_default;
argc = parse_options(argc, argv, builtin_merge_options,
builtin_merge_usage, 0);
if (squash) {
if (!allow_fast_forward)
die("You cannot combine --squash with --no-ff.");
option_commit = 0;
}
if (!argc)
usage_with_options(builtin_merge_usage,
builtin_merge_options);
/*
* This could be traditional "merge <msg> HEAD <commit>..." and
* the way we can tell it is to see if the second token is HEAD,
* but some people might have misused the interface and used a
* committish that is the same as HEAD there instead.
* Traditional format never would have "-m" so it is an
* additional safety measure to check for it.
*/
strbuf_init(&buf, 0);
if (!have_message && is_old_style_invocation(argc, argv)) {
strbuf_addstr(&merge_msg, argv[0]);
head_arg = argv[1];
argv += 2;
argc -= 2;
} else if (head_invalid) {
struct object *remote_head;
/*
* If the merged head is a valid one there is no reason
* to forbid "git merge" into a branch yet to be born.
* We do the same for "git pull".
*/
if (argc != 1)
die("Can merge only exactly one commit into "
"empty head");
remote_head = peel_to_type(argv[0], 0, NULL, OBJ_COMMIT);
if (!remote_head)
die("%s - not something we can merge", argv[0]);
update_ref("initial pull", "HEAD", remote_head->sha1, NULL, 0,
DIE_ON_ERR);
reset_hard(remote_head->sha1, 0);
return 0;
} else {
struct strbuf msg;
/* We are invoked directly as the first-class UI. */
head_arg = "HEAD";
/*
* All the rest are the commits being merged;
* prepare the standard merge summary message to
* be appended to the given message. If remote
* is invalid we will die later in the common
* codepath so we discard the error in this
* loop.
*/
strbuf_init(&msg, 0);
for (i = 0; i < argc; i++)
merge_name(argv[i], &msg);
fmt_merge_msg(option_log, &msg, &merge_msg);
if (merge_msg.len)
strbuf_setlen(&merge_msg, merge_msg.len-1);
}
if (head_invalid || !argc)
usage_with_options(builtin_merge_usage,
builtin_merge_options);
strbuf_addstr(&buf, "merge");
for (i = 0; i < argc; i++)
strbuf_addf(&buf, " %s", argv[i]);
setenv("GIT_REFLOG_ACTION", buf.buf, 0);
strbuf_reset(&buf);
for (i = 0; i < argc; i++) {
struct object *o;
o = peel_to_type(argv[i], 0, NULL, OBJ_COMMIT);
if (!o)
die("%s - not something we can merge", argv[i]);
remotes = &commit_list_insert(lookup_commit(o->sha1),
remotes)->next;
strbuf_addf(&buf, "GITHEAD_%s", sha1_to_hex(o->sha1));
setenv(buf.buf, argv[i], 1);
strbuf_reset(&buf);
}
if (!use_strategies) {
if (!remoteheads->next)
add_strategies(pull_twohead, DEFAULT_TWOHEAD);
else
add_strategies(pull_octopus, DEFAULT_OCTOPUS);
}
for (i = 0; i < use_strategies_nr; i++) {
if (use_strategies[i]->attr & NO_FAST_FORWARD)
allow_fast_forward = 0;
if (use_strategies[i]->attr & NO_TRIVIAL)
allow_trivial = 0;
}
if (!remoteheads->next)
common = get_merge_bases(lookup_commit(head),
remoteheads->item, 1);
else {
struct commit_list *list = remoteheads;
commit_list_insert(lookup_commit(head), &list);
common = get_octopus_merge_bases(list);
free(list);
}
update_ref("updating ORIG_HEAD", "ORIG_HEAD", head, NULL, 0,
DIE_ON_ERR);
if (!common)
; /* No common ancestors found. We need a real merge. */
else if (!remoteheads->next && !common->next &&
common->item == remoteheads->item) {
/*
* If head can reach all the merge then we are up to date.
* but first the most common case of merging one remote.
*/
finish_up_to_date("Already up-to-date.");
return 0;
} else if (allow_fast_forward && !remoteheads->next &&
!common->next &&
!hashcmp(common->item->object.sha1, head)) {
/* Again the most common case of merging one remote. */
struct strbuf msg;
struct object *o;
char hex[41];
strcpy(hex, find_unique_abbrev(head, DEFAULT_ABBREV));
printf("Updating %s..%s\n",
hex,
find_unique_abbrev(remoteheads->item->object.sha1,
DEFAULT_ABBREV));
refresh_cache(REFRESH_QUIET);
strbuf_init(&msg, 0);
strbuf_addstr(&msg, "Fast forward");
if (have_message)
strbuf_addstr(&msg,
" (no commit created; -m option ignored)");
o = peel_to_type(sha1_to_hex(remoteheads->item->object.sha1),
0, NULL, OBJ_COMMIT);
if (!o)
return 1;
if (checkout_fast_forward(head, remoteheads->item->object.sha1))
return 1;
finish(o->sha1, msg.buf);
drop_save();
return 0;
} else if (!remoteheads->next && common->next)
;
/*
* We are not doing octopus and not fast forward. Need
* a real merge.
*/
else if (!remoteheads->next && !common->next && option_commit) {
/*
* We are not doing octopus, not fast forward, and have
* only one common.
*/
refresh_cache(REFRESH_QUIET);
if (allow_trivial) {
/* See if it is really trivial. */
git_committer_info(IDENT_ERROR_ON_NO_NAME);
printf("Trying really trivial in-index merge...\n");
if (!read_tree_trivial(common->item->object.sha1,
head, remoteheads->item->object.sha1))
return merge_trivial();
printf("Nope.\n");
}
} else {
/*
* An octopus. If we can reach all the remote we are up
* to date.
*/
int up_to_date = 1;
struct commit_list *j;
for (j = remoteheads; j; j = j->next) {
struct commit_list *common_one;
/*
* Here we *have* to calculate the individual
* merge_bases again, otherwise "git merge HEAD^
* HEAD^^" would be missed.
*/
common_one = get_merge_bases(lookup_commit(head),
j->item, 1);
if (hashcmp(common_one->item->object.sha1,
j->item->object.sha1)) {
up_to_date = 0;
break;
}
}
if (up_to_date) {
finish_up_to_date("Already up-to-date. Yeeah!");
return 0;
}
}
/* We are going to make a new commit. */
git_committer_info(IDENT_ERROR_ON_NO_NAME);
/*
* At this point, we need a real merge. No matter what strategy
* we use, it would operate on the index, possibly affecting the
* working tree, and when resolved cleanly, have the desired
* tree in the index -- this means that the index must be in
* sync with the head commit. The strategies are responsible
* to ensure this.
*/
if (use_strategies_nr != 1) {
/*
* Stash away the local changes so that we can try more
* than one.
*/
save_state();
} else {
memcpy(stash, null_sha1, 20);
}
for (i = 0; i < use_strategies_nr; i++) {
int ret;
if (i) {
printf("Rewinding the tree to pristine...\n");
restore_state();
}
if (use_strategies_nr != 1)
printf("Trying merge strategy %s...\n",
use_strategies[i]->name);
/*
* Remember which strategy left the state in the working
* tree.
*/
wt_strategy = use_strategies[i]->name;
ret = try_merge_strategy(use_strategies[i]->name,
common, head_arg);
if (!option_commit && !ret) {
merge_was_ok = 1;
/*
* This is necessary here just to avoid writing
* the tree, but later we will *not* exit with
* status code 1 because merge_was_ok is set.
*/
ret = 1;
}
if (ret) {
/*
* The backend exits with 1 when conflicts are
* left to be resolved, with 2 when it does not
* handle the given merge at all.
*/
if (ret == 1) {
int cnt = evaluate_result();
if (best_cnt <= 0 || cnt <= best_cnt) {
best_strategy = use_strategies[i]->name;
best_cnt = cnt;
}
}
if (merge_was_ok)
break;
else
continue;
}
/* Automerge succeeded. */
write_tree_trivial(result_tree);
automerge_was_ok = 1;
break;
}
/*
* If we have a resulting tree, that means the strategy module
* auto resolved the merge cleanly.
*/
if (automerge_was_ok)
return finish_automerge(common, result_tree, wt_strategy);
/*
* Pick the result from the best strategy and have the user fix
* it up.
*/
if (!best_strategy) {
restore_state();
if (use_strategies_nr > 1)
fprintf(stderr,
"No merge strategy handled the merge.\n");
else
fprintf(stderr, "Merge with strategy %s failed.\n",
use_strategies[0]->name);
return 2;
} else if (best_strategy == wt_strategy)
; /* We already have its result in the working tree. */
else {
printf("Rewinding the tree to pristine...\n");
restore_state();
printf("Using the %s to prepare resolving by hand.\n",
best_strategy);
try_merge_strategy(best_strategy, common, head_arg);
}
if (squash)
finish(NULL, NULL);
else {
int fd;
struct commit_list *j;
for (j = remoteheads; j; j = j->next)
strbuf_addf(&buf, "%s\n",
sha1_to_hex(j->item->object.sha1));
fd = open(git_path("MERGE_HEAD"), O_WRONLY | O_CREAT, 0666);
if (fd < 0)
die("Could open %s for writing",
git_path("MERGE_HEAD"));
if (write_in_full(fd, buf.buf, buf.len) != buf.len)
die("Could not write to %s", git_path("MERGE_HEAD"));
close(fd);
strbuf_addch(&merge_msg, '\n');
fd = open(git_path("MERGE_MSG"), O_WRONLY | O_CREAT, 0666);
if (fd < 0)
die("Could open %s for writing", git_path("MERGE_MSG"));
if (write_in_full(fd, merge_msg.buf, merge_msg.len) !=
merge_msg.len)
die("Could not write to %s", git_path("MERGE_MSG"));
close(fd);
}
if (merge_was_ok) {
fprintf(stderr, "Automatic merge went well; "
"stopped before committing as requested\n");
return 0;
} else
return suggest_conflicts();
}