static int finish_automerge(struct commit *head,
int head_subsumed,
struct commit_list *common,
struct commit_list *remoteheads,
unsigned char *result_tree,
const char *wt_strategy)
{
struct commit_list *parents = NULL;
struct strbuf buf = STRBUF_INIT;
unsigned char result_commit[20];
free_commit_list(common);
parents = remoteheads;
if (!head_subsumed || !allow_fast_forward)
commit_list_insert(head, &parents);
strbuf_addch(&merge_msg, '\n');
prepare_to_commit(remoteheads);
if (commit_tree(&merge_msg, result_tree, parents, result_commit,
NULL, sign_commit))
die(_("failed to write commit object"));
strbuf_addf(&buf, "Merge made by the '%s' strategy.", wt_strategy);
finish(head, remoteheads, result_commit, buf.buf);
strbuf_release(&buf);
drop_save();
return 0;
}
static int finish_automerge(struct commit_list *common,
unsigned char *result_tree,
const char *wt_strategy)
{
struct commit_list *parents = NULL, *j;
struct strbuf buf = STRBUF_INIT;
unsigned char result_commit[20];
free_commit_list(common);
if (allow_fast_forward) {
parents = remoteheads;
commit_list_insert(lookup_commit(head), &parents);
parents = reduce_heads(parents);
} else {
struct commit_list **pptr = &parents;
pptr = &commit_list_insert(lookup_commit(head),
pptr)->next;
for (j = remoteheads; j; j = j->next)
pptr = &commit_list_insert(j->item, pptr)->next;
}
free_commit_list(remoteheads);
strbuf_addch(&merge_msg, '\n');
run_prepare_commit_msg();
commit_tree(merge_msg.buf, result_tree, parents, result_commit, NULL);
strbuf_addf(&buf, "Merge made by %s.", wt_strategy);
finish(result_commit, buf.buf);
strbuf_release(&buf);
drop_save();
return 0;
}
static int finish_automerge(struct commit *head,
struct commit_list *common,
unsigned char *result_tree,
const char *wt_strategy)
{
struct commit_list *parents = NULL, *j;
struct strbuf buf = STRBUF_INIT;
unsigned char result_commit[20];
free_commit_list(common);
if (allow_fast_forward) {
parents = remoteheads;
commit_list_insert(head, &parents);
parents = reduce_heads(parents);
} else {
struct commit_list **pptr = &parents;
pptr = &commit_list_insert(head,
pptr)->next;
for (j = remoteheads; j; j = j->next)
pptr = &commit_list_insert(j->item, pptr)->next;
}
strbuf_addch(&merge_msg, '\n');
prepare_to_commit();
free_commit_list(remoteheads);
if (commit_tree(&merge_msg, result_tree, parents, result_commit,
NULL, sign_commit))
die(_("failed to write commit object"));
strbuf_addf(&buf, "Merge made by the '%s' strategy.", wt_strategy);
finish(head, result_commit, buf.buf);
strbuf_release(&buf);
drop_save();
return 0;
}
static int merge_trivial(struct commit *head, struct commit_list *remoteheads)
{
unsigned char result_tree[20], result_commit[20];
struct commit_list *parents, **pptr = &parents;
static struct lock_file lock;
hold_locked_index(&lock, 1);
refresh_cache(REFRESH_QUIET);
if (active_cache_changed &&
write_locked_index(&the_index, &lock, COMMIT_LOCK))
return error(_("Unable to write index."));
rollback_lock_file(&lock);
write_tree_trivial(result_tree);
printf(_("Wonderful.\n"));
pptr = commit_list_append(head, pptr);
pptr = commit_list_append(remoteheads->item, pptr);
prepare_to_commit(remoteheads);
if (commit_tree(merge_msg.buf, merge_msg.len, result_tree, parents,
result_commit, NULL, sign_commit))
die(_("failed to write commit object"));
finish(head, remoteheads, result_commit, "In-index merge");
drop_save();
return 0;
}
static int merge_trivial(void)
{
unsigned char result_tree[20], result_commit[20];
struct commit_list parent;
write_tree_trivial(result_tree);
printf("Wonderful.\n");
parent.item = remoteheads->item;
parent.next = NULL;
commit_tree(merge_msg.buf, result_tree, &parent, result_commit);
finish(result_commit, "In-index merge");
drop_save();
return 0;
}
static int merge_trivial(void)
{
unsigned char result_tree[20], result_commit[20];
struct commit_list *parent = xmalloc(sizeof(*parent));
write_tree_trivial(result_tree);
printf("Wonderful.\n");
parent->item = lookup_commit(head);
parent->next = xmalloc(sizeof(*parent->next));
parent->next->item = remoteheads->item;
parent->next->next = NULL;
commit_tree(merge_msg.buf, result_tree, parent, result_commit, NULL);
finish(result_commit, "In-index merge");
drop_save();
return 0;
}
static int merge_trivial(struct commit *head, struct commit_list *remoteheads)
{
unsigned char result_tree[20], result_commit[20];
struct commit_list *parents, **pptr = &parents;
write_tree_trivial(result_tree);
printf(_("Wonderful.\n"));
pptr = commit_list_append(head, pptr);
pptr = commit_list_append(remoteheads->item, pptr);
prepare_to_commit(remoteheads);
if (commit_tree(merge_msg.buf, merge_msg.len, result_tree, parents,
result_commit, NULL, sign_commit))
die(_("failed to write commit object"));
finish(head, remoteheads, result_commit, "In-index merge");
drop_save();
return 0;
}
static int merge_trivial(struct commit *head, struct commit_list *remoteheads)
{
unsigned char result_tree[20], result_commit[20];
struct commit_list *parent = xmalloc(sizeof(*parent));
write_tree_trivial(result_tree);
printf(_("Wonderful.\n"));
parent->item = head;
parent->next = xmalloc(sizeof(*parent->next));
parent->next->item = remoteheads->item;
parent->next->next = NULL;
prepare_to_commit(remoteheads);
if (commit_tree(&merge_msg, result_tree, parent, result_commit, NULL,
sign_commit))
die(_("failed to write commit object"));
finish(head, remoteheads, result_commit, "In-index merge");
drop_save();
return 0;
}
/* This is called when no merge was necessary. */
static void finish_up_to_date(const char *msg)
{
if (verbosity >= 0)
printf("%s%s\n", squash ? _(" (nothing to squash)") : "", msg);
drop_save();
}
int cmd_merge(int argc, const char **argv, const char *prefix)
{
unsigned char result_tree[20];
unsigned char stash[20];
unsigned char head_sha1[20];
struct commit *head_commit;
struct strbuf buf = STRBUF_INIT;
const char *head_arg;
int flag, i, ret = 0, head_subsumed;
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 *remoteheads, *p;
void *branch_to_free;
if (argc == 2 && !strcmp(argv[1], "-h"))
usage_with_options(builtin_merge_usage, builtin_merge_options);
/*
* Check if we are _not_ on a detached HEAD, i.e. if there is a
* current branch.
*/
branch = branch_to_free = resolve_refdup("HEAD", head_sha1, 0, &flag);
if (branch && !prefixcmp(branch, "refs/heads/"))
branch += 11;
if (!branch || is_null_sha1(head_sha1))
head_commit = NULL;
else
head_commit = lookup_commit_or_die(head_sha1, "HEAD");
git_config(git_merge_config, NULL);
if (branch_mergeoptions)
parse_branch_merge_options(branch_mergeoptions);
argc = parse_options(argc, argv, prefix, builtin_merge_options,
builtin_merge_usage, 0);
if (shortlog_len < 0)
shortlog_len = (merge_log_config > 0) ? merge_log_config : 0;
if (verbosity < 0 && show_progress == -1)
show_progress = 0;
if (abort_current_merge) {
int nargc = 2;
const char *nargv[] = {"reset", "--merge", NULL};
if (!file_exists(git_path("MERGE_HEAD")))
die(_("There is no merge to abort (MERGE_HEAD missing)."));
/* Invoke 'git reset --merge' */
ret = cmd_reset(nargc, nargv, prefix);
goto done;
}
if (read_cache_unmerged())
die_resolve_conflict("merge");
if (file_exists(git_path("MERGE_HEAD"))) {
/*
* There is no unmerged entry, don't advise 'git
* add/rm <file>', just 'git commit'.
*/
if (advice_resolve_conflict)
die(_("You have not concluded your merge (MERGE_HEAD exists).\n"
"Please, commit your changes before you can merge."));
else
die(_("You have not concluded your merge (MERGE_HEAD exists)."));
}
if (file_exists(git_path("CHERRY_PICK_HEAD"))) {
if (advice_resolve_conflict)
die(_("You have not concluded your cherry-pick (CHERRY_PICK_HEAD exists).\n"
"Please, commit your changes before you can merge."));
else
die(_("You have not concluded your cherry-pick (CHERRY_PICK_HEAD exists)."));
}
resolve_undo_clear();
if (verbosity < 0)
show_diffstat = 0;
if (squash) {
if (!allow_fast_forward)
die(_("You cannot combine --squash with --no-ff."));
option_commit = 0;
}
if (!allow_fast_forward && fast_forward_only)
die(_("You cannot combine --no-ff with --ff-only."));
if (!abort_current_merge) {
if (!argc) {
if (default_to_upstream)
argc = setup_with_upstream(&argv);
else
die(_("No commit specified and merge.defaultToUpstream not set."));
} else if (argc == 1 && !strcmp(argv[0], "-"))
argv[0] = "@{-1}";
}
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.
*/
if (!have_message && head_commit &&
is_old_style_invocation(argc, argv, head_commit->object.sha1)) {
strbuf_addstr(&merge_msg, argv[0]);
head_arg = argv[1];
argv += 2;
argc -= 2;
remoteheads = collect_parents(head_commit, &head_subsumed, argc, argv);
} else if (!head_commit) {
struct commit *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"));
if (squash)
die(_("Squash commit into empty head not supported yet"));
if (!allow_fast_forward)
die(_("Non-fast-forward commit does not make sense into "
"an empty head"));
remoteheads = collect_parents(head_commit, &head_subsumed, argc, argv);
remote_head = remoteheads->item;
if (!remote_head)
die(_("%s - not something we can merge"), argv[0]);
read_empty(remote_head->object.sha1, 0);
update_ref("initial pull", "HEAD", remote_head->object.sha1,
NULL, 0, DIE_ON_ERR);
goto done;
} else {
struct strbuf merge_names = STRBUF_INIT;
/* 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.
*/
remoteheads = collect_parents(head_commit, &head_subsumed, argc, argv);
for (p = remoteheads; p; p = p->next)
merge_name(merge_remote_util(p->item)->name, &merge_names);
if (!have_message || shortlog_len) {
struct fmt_merge_msg_opts opts;
memset(&opts, 0, sizeof(opts));
opts.add_title = !have_message;
opts.shortlog_len = shortlog_len;
fmt_merge_msg(&merge_names, &merge_msg, &opts);
if (merge_msg.len)
strbuf_setlen(&merge_msg, merge_msg.len - 1);
}
}
if (!head_commit || !argc)
usage_with_options(builtin_merge_usage,
builtin_merge_options);
strbuf_addstr(&buf, "merge");
for (p = remoteheads; p; p = p->next)
strbuf_addf(&buf, " %s", merge_remote_util(p->item)->name);
setenv("GIT_REFLOG_ACTION", buf.buf, 0);
strbuf_reset(&buf);
for (p = remoteheads; p; p = p->next) {
struct commit *commit = p->item;
strbuf_addf(&buf, "GITHEAD_%s",
sha1_to_hex(commit->object.sha1));
setenv(buf.buf, merge_remote_util(commit)->name, 1);
strbuf_reset(&buf);
if (!fast_forward_only &&
merge_remote_util(commit) &&
merge_remote_util(commit)->obj &&
merge_remote_util(commit)->obj->type == OBJ_TAG)
allow_fast_forward = 0;
}
if (option_edit < 0)
option_edit = default_edit_option();
if (!use_strategies) {
if (!remoteheads)
; /* already up-to-date */
else 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)
; /* already up-to-date */
else if (!remoteheads->next)
common = get_merge_bases(head_commit, remoteheads->item, 1);
else {
struct commit_list *list = remoteheads;
commit_list_insert(head_commit, &list);
common = get_octopus_merge_bases(list);
free(list);
}
update_ref("updating ORIG_HEAD", "ORIG_HEAD", head_commit->object.sha1,
NULL, 0, DIE_ON_ERR);
if (remoteheads && !common)
; /* No common ancestors found. We need a real merge. */
else if (!remoteheads ||
(!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.");
goto done;
} else if (allow_fast_forward && !remoteheads->next &&
!common->next &&
!hashcmp(common->item->object.sha1, head_commit->object.sha1)) {
/* Again the most common case of merging one remote. */
struct strbuf msg = STRBUF_INIT;
struct commit *commit;
char hex[41];
strcpy(hex, find_unique_abbrev(head_commit->object.sha1, DEFAULT_ABBREV));
if (verbosity >= 0)
printf(_("Updating %s..%s\n"),
hex,
find_unique_abbrev(remoteheads->item->object.sha1,
DEFAULT_ABBREV));
strbuf_addstr(&msg, "Fast-forward");
if (have_message)
strbuf_addstr(&msg,
" (no commit created; -m option ignored)");
commit = remoteheads->item;
if (!commit) {
ret = 1;
goto done;
}
if (checkout_fast_forward(head_commit->object.sha1,
commit->object.sha1,
overwrite_ignore)) {
ret = 1;
goto done;
}
finish(head_commit, remoteheads, commit->object.sha1, msg.buf);
drop_save();
goto done;
} 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 && !fast_forward_only) {
/* See if it is really trivial. */
git_committer_info(IDENT_STRICT);
printf(_("Trying really trivial in-index merge...\n"));
if (!read_tree_trivial(common->item->object.sha1,
head_commit->object.sha1,
remoteheads->item->object.sha1)) {
ret = merge_trivial(head_commit, remoteheads);
goto done;
}
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(head_commit, 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!");
goto done;
}
}
if (fast_forward_only)
die(_("Not possible to fast-forward, aborting."));
/* We are going to make a new commit. */
git_committer_info(IDENT_STRICT);
/*
* 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(stash))
hashcpy(stash, null_sha1);
for (i = 0; i < use_strategies_nr; i++) {
int ret;
if (i) {
printf(_("Rewinding the tree to pristine...\n"));
restore_state(head_commit->object.sha1, stash);
}
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, remoteheads,
head_commit, 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) {
ret = finish_automerge(head_commit, head_subsumed,
common, remoteheads,
result_tree, wt_strategy);
goto done;
}
/*
* Pick the result from the best strategy and have the user fix
* it up.
*/
if (!best_strategy) {
restore_state(head_commit->object.sha1, stash);
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);
ret = 2;
goto done;
} 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(head_commit->object.sha1, stash);
printf(_("Using the %s to prepare resolving by hand.\n"),
best_strategy);
try_merge_strategy(best_strategy, common, remoteheads,
head_commit, head_arg);
}
if (squash)
finish(head_commit, remoteheads, NULL, NULL);
else
write_merge_state(remoteheads);
if (merge_was_ok)
fprintf(stderr, _("Automatic merge went well; "
"stopped before committing as requested\n"));
else
ret = suggest_conflicts(option_renormalize);
done:
free(branch_to_free);
return ret;
}
int cmd_merge(int argc, const char **argv, const char *prefix)
{
unsigned char result_tree[20];
struct strbuf buf = STRBUF_INIT;
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;
if (file_exists(git_path("MERGE_HEAD")))
die("You have not concluded your merge. (MERGE_HEAD exists)");
if (read_cache_unmerged())
die("You are in the middle of a conflicted merge."
" (index unmerged)");
/*
* 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, prefix, builtin_merge_options,
builtin_merge_usage, 0);
if (verbosity < 0)
show_diffstat = 0;
if (squash) {
if (!allow_fast_forward)
die("You cannot combine --squash with --no-ff.");
option_commit = 0;
}
if (!allow_fast_forward && fast_forward_only)
die("You cannot combine --no-ff with --ff-only.");
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.
*/
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");
if (squash)
die("Squash commit into empty head not supported yet");
if (!allow_fast_forward)
die("Non-fast-forward commit does not make sense into "
"an 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 = STRBUF_INIT;
/* 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.
*/
if (!have_message) {
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;
struct commit *commit;
o = peel_to_type(argv[i], 0, NULL, OBJ_COMMIT);
if (!o)
die("%s - not something we can merge", argv[i]);
commit = lookup_commit(o->sha1);
commit->util = (void *)argv[i];
remotes = &commit_list_insert(commit, 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 = STRBUF_INIT;
struct object *o;
char hex[41];
strcpy(hex, find_unique_abbrev(head, DEFAULT_ABBREV));
if (verbosity >= 0)
printf("Updating %s..%s\n",
hex,
find_unique_abbrev(remoteheads->item->object.sha1,
DEFAULT_ABBREV));
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 && !fast_forward_only) {
/* 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;
}
}
if (fast_forward_only)
die("Not possible to fast-forward, aborting.");
/* 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_errno("Could not open '%s' for writing",
git_path("MERGE_HEAD"));
if (write_in_full(fd, buf.buf, buf.len) != buf.len)
die_errno("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_errno("Could not open '%s' for writing",
git_path("MERGE_MSG"));
if (write_in_full(fd, merge_msg.buf, merge_msg.len) !=
merge_msg.len)
die_errno("Could not write to '%s'", git_path("MERGE_MSG"));
close(fd);
fd = open(git_path("MERGE_MODE"), O_WRONLY | O_CREAT | O_TRUNC, 0666);
if (fd < 0)
die_errno("Could not open '%s' for writing",
git_path("MERGE_MODE"));
strbuf_reset(&buf);
if (!allow_fast_forward)
strbuf_addf(&buf, "no-ff");
if (write_in_full(fd, buf.buf, buf.len) != buf.len)
die_errno("Could not write to '%s'", git_path("MERGE_MODE"));
close(fd);
}
if (merge_was_ok) {
fprintf(stderr, "Automatic merge went well; "
"stopped before committing as requested\n");
return 0;
} else
return suggest_conflicts();
}
/* This is called when no merge was necessary. */
static void finish_up_to_date(const char *msg)
{
printf("%s%s\n", squash ? " (nothing to squash)" : "", msg);
drop_save();
}