[thirdparty/git.git] / builtin / rebase.c

/*
 * "git rebase" builtin command
 *
 * Copyright (c) 2018 Pratik Karki
 */

#include "builtin.h"
#include "run-command.h"
#include "exec-cmd.h"
#include "argv-array.h"
#include "dir.h"
#include "packfile.h"
#include "refs.h"
#include "quote.h"
#include "config.h"
#include "cache-tree.h"
#include "unpack-trees.h"
#include "lockfile.h"
#include "parse-options.h"
#include "commit.h"
#include "diff.h"
#include "wt-status.h"

static char const * const builtin_rebase_usage[] = {
	N_("git rebase [-i] [options] [--exec <cmd>] [--onto <newbase>] "
		"[<upstream>] [<branch>]"),
	N_("git rebase [-i] [options] [--exec <cmd>] [--onto <newbase>] "
		"--root [<branch>]"),
	N_("git rebase --continue | --abort | --skip | --edit-todo"),
	NULL
};

static GIT_PATH_FUNC(apply_dir, "rebase-apply")
static GIT_PATH_FUNC(merge_dir, "rebase-merge")

enum rebase_type {
	REBASE_UNSPECIFIED = -1,
	REBASE_AM,
	REBASE_MERGE,
	REBASE_INTERACTIVE,
	REBASE_PRESERVE_MERGES
};

static int use_builtin_rebase(void)
{
	struct child_process cp = CHILD_PROCESS_INIT;
	struct strbuf out = STRBUF_INIT;
	int ret;

	argv_array_pushl(&cp.args,
			 "config", "--bool", "rebase.usebuiltin", NULL);
	cp.git_cmd = 1;
	if (capture_command(&cp, &out, 6)) {
		strbuf_release(&out);
		return 0;
	}

	strbuf_trim(&out);
	ret = !strcmp("true", out.buf);
	strbuf_release(&out);
	return ret;
}

static int apply_autostash(void)
{
	warning("TODO");
	return 0;
}

struct rebase_options {
	enum rebase_type type;
	const char *state_dir;
	struct commit *upstream;
	const char *upstream_name;
	const char *upstream_arg;
	char *head_name;
	struct object_id orig_head;
	struct commit *onto;
	const char *onto_name;
	const char *revisions;
	int root;
	struct commit *restrict_revision;
	int dont_finish_rebase;
	enum {
		REBASE_NO_QUIET = 1<<0,
		REBASE_VERBOSE = 1<<1,
		REBASE_DIFFSTAT = 1<<2,
	} flags;
	struct strbuf git_am_opt;
};

/* Returns the filename prefixed by the state_dir */
static const char *state_dir_path(const char *filename, struct rebase_options *opts)
{
	static struct strbuf path = STRBUF_INIT;
	static size_t prefix_len;

	if (!prefix_len) {
		strbuf_addf(&path, "%s/", opts->state_dir);
		prefix_len = path.len;
	}

	strbuf_setlen(&path, prefix_len);
	strbuf_addstr(&path, filename);
	return path.buf;
}

static int finish_rebase(struct rebase_options *opts)
{
	struct strbuf dir = STRBUF_INIT;
	const char *argv_gc_auto[] = { "gc", "--auto", NULL };

	delete_ref(NULL, "REBASE_HEAD", NULL, REF_NO_DEREF);
	apply_autostash();
	close_all_packs(the_repository->objects);
	/*
	 * We ignore errors in 'gc --auto', since the
	 * user should see them.
	 */
	run_command_v_opt(argv_gc_auto, RUN_GIT_CMD);
	strbuf_addstr(&dir, opts->state_dir);
	remove_dir_recursively(&dir, 0);
	strbuf_release(&dir);

	return 0;
}

static struct commit *peel_committish(const char *name)
{
	struct object *obj;
	struct object_id oid;

	if (get_oid(name, &oid))
		return NULL;
	obj = parse_object(the_repository, &oid);
	return (struct commit *)peel_to_type(name, 0, obj, OBJ_COMMIT);
}

static void add_var(struct strbuf *buf, const char *name, const char *value)
{
	if (!value)
		strbuf_addf(buf, "unset %s; ", name);
	else {
		strbuf_addf(buf, "%s=", name);
		sq_quote_buf(buf, value);
		strbuf_addstr(buf, "; ");
	}
}

static int run_specific_rebase(struct rebase_options *opts)
{
	const char *argv[] = { NULL, NULL };
	struct strbuf script_snippet = STRBUF_INIT;
	int status;
	const char *backend, *backend_func;

	add_var(&script_snippet, "GIT_DIR", absolute_path(get_git_dir()));
	add_var(&script_snippet, "state_dir", opts->state_dir);

	add_var(&script_snippet, "upstream_name", opts->upstream_name);
	add_var(&script_snippet, "upstream",
				 oid_to_hex(&opts->upstream->object.oid));
	add_var(&script_snippet, "head_name", opts->head_name);
	add_var(&script_snippet, "orig_head", oid_to_hex(&opts->orig_head));
	add_var(&script_snippet, "onto", oid_to_hex(&opts->onto->object.oid));
	add_var(&script_snippet, "onto_name", opts->onto_name);
	add_var(&script_snippet, "revisions", opts->revisions);
	add_var(&script_snippet, "restrict_revision", opts->restrict_revision ?
		oid_to_hex(&opts->restrict_revision->object.oid) : NULL);
	add_var(&script_snippet, "GIT_QUIET",
		opts->flags & REBASE_NO_QUIET ? "" : "t");
	add_var(&script_snippet, "git_am_opt", opts->git_am_opt.buf);
	add_var(&script_snippet, "verbose",
		opts->flags & REBASE_VERBOSE ? "t" : "");
	add_var(&script_snippet, "diffstat",
		opts->flags & REBASE_DIFFSTAT ? "t" : "");

	switch (opts->type) {
	case REBASE_AM:
		backend = "git-rebase--am";
		backend_func = "git_rebase__am";
		break;
	case REBASE_INTERACTIVE:
		backend = "git-rebase--interactive";
		backend_func = "git_rebase__interactive";
		break;
	case REBASE_MERGE:
		backend = "git-rebase--merge";
		backend_func = "git_rebase__merge";
		break;
	case REBASE_PRESERVE_MERGES:
		backend = "git-rebase--preserve-merges";
		backend_func = "git_rebase__preserve_merges";
		break;
	default:
		BUG("Unhandled rebase type %d", opts->type);
		break;
	}

	strbuf_addf(&script_snippet,
		    ". git-sh-setup && . git-rebase--common &&"
		    " . %s && %s", backend, backend_func);
	argv[0] = script_snippet.buf;

	status = run_command_v_opt(argv, RUN_USING_SHELL);
	if (opts->dont_finish_rebase)
		; /* do nothing */
	else if (status == 0) {
		if (!file_exists(state_dir_path("stopped-sha", opts)))
			finish_rebase(opts);
	} else if (status == 2) {
		struct strbuf dir = STRBUF_INIT;

		apply_autostash();
		strbuf_addstr(&dir, opts->state_dir);
		remove_dir_recursively(&dir, 0);
		strbuf_release(&dir);
		die("Nothing to do");
	}

	strbuf_release(&script_snippet);

	return status ? -1 : 0;
}

#define GIT_REFLOG_ACTION_ENVIRONMENT "GIT_REFLOG_ACTION"

static int reset_head(struct object_id *oid, const char *action,
		      const char *switch_to_branch, int detach_head)
{
	struct object_id head_oid;
	struct tree_desc desc;
	struct lock_file lock = LOCK_INIT;
	struct unpack_trees_options unpack_tree_opts;
	struct tree *tree;
	const char *reflog_action;
	struct strbuf msg = STRBUF_INIT;
	size_t prefix_len;
	struct object_id *orig = NULL, oid_orig,
		*old_orig = NULL, oid_old_orig;
	int ret = 0;

	if (hold_locked_index(&lock, LOCK_REPORT_ON_ERROR) < 0)
		return -1;

	if (!oid) {
		if (get_oid("HEAD", &head_oid)) {
			rollback_lock_file(&lock);
			return error(_("could not determine HEAD revision"));
		}
		oid = &head_oid;
	}

	memset(&unpack_tree_opts, 0, sizeof(unpack_tree_opts));
	setup_unpack_trees_porcelain(&unpack_tree_opts, action);
	unpack_tree_opts.head_idx = 1;
	unpack_tree_opts.src_index = the_repository->index;
	unpack_tree_opts.dst_index = the_repository->index;
	unpack_tree_opts.fn = oneway_merge;
	unpack_tree_opts.update = 1;
	unpack_tree_opts.merge = 1;
	if (!detach_head)
		unpack_tree_opts.reset = 1;

	if (read_index_unmerged(the_repository->index) < 0) {
		rollback_lock_file(&lock);
		return error(_("could not read index"));
	}

	if (!fill_tree_descriptor(&desc, oid)) {
		error(_("failed to find tree of %s"), oid_to_hex(oid));
		rollback_lock_file(&lock);
		free((void *)desc.buffer);
		return -1;
	}

	if (unpack_trees(1, &desc, &unpack_tree_opts)) {
		rollback_lock_file(&lock);
		free((void *)desc.buffer);
		return -1;
	}

	tree = parse_tree_indirect(oid);
	prime_cache_tree(the_repository->index, tree);

	if (write_locked_index(the_repository->index, &lock, COMMIT_LOCK) < 0)
		ret = error(_("could not write index"));
	free((void *)desc.buffer);

	if (ret)
		return ret;

	reflog_action = getenv(GIT_REFLOG_ACTION_ENVIRONMENT);
	strbuf_addf(&msg, "%s: ", reflog_action ? reflog_action : "rebase");
	prefix_len = msg.len;

	if (!get_oid("ORIG_HEAD", &oid_old_orig))
		old_orig = &oid_old_orig;
	if (!get_oid("HEAD", &oid_orig)) {
		orig = &oid_orig;
		strbuf_addstr(&msg, "updating ORIG_HEAD");
		update_ref(msg.buf, "ORIG_HEAD", orig, old_orig, 0,
			   UPDATE_REFS_MSG_ON_ERR);
	} else if (old_orig)
		delete_ref(NULL, "ORIG_HEAD", old_orig, 0);
	strbuf_setlen(&msg, prefix_len);
	strbuf_addstr(&msg, "updating HEAD");
	if (!switch_to_branch)
		ret = update_ref(msg.buf, "HEAD", oid, orig, REF_NO_DEREF,
				 UPDATE_REFS_MSG_ON_ERR);
	else {
		ret = create_symref("HEAD", switch_to_branch, msg.buf);
		if (!ret)
			ret = update_ref(msg.buf, "HEAD", oid, NULL, 0,
					 UPDATE_REFS_MSG_ON_ERR);
	}

	strbuf_release(&msg);
	return ret;
}

static int rebase_config(const char *var, const char *value, void *data)
{
	struct rebase_options *opts = data;

	if (!strcmp(var, "rebase.stat")) {
		if (git_config_bool(var, value))
			opts->flags |= REBASE_DIFFSTAT;
		else
			opts->flags &= !REBASE_DIFFSTAT;
		return 0;
	}

	return git_default_config(var, value, data);
}

int cmd_rebase(int argc, const char **argv, const char *prefix)
{
	struct rebase_options options = {
		.type = REBASE_UNSPECIFIED,
		.flags = REBASE_NO_QUIET,
		.git_am_opt = STRBUF_INIT,
	};
	const char *branch_name;
	int ret, flags;
	int ok_to_skip_pre_rebase = 0;
	struct strbuf msg = STRBUF_INIT;
	struct strbuf revisions = STRBUF_INIT;
	struct object_id merge_base;
	struct option builtin_rebase_options[] = {
		OPT_STRING(0, "onto", &options.onto_name,
			   N_("revision"),
			   N_("rebase onto given branch instead of upstream")),
		OPT_BOOL(0, "no-verify", &ok_to_skip_pre_rebase,
			 N_("allow pre-rebase hook to run")),
		OPT_NEGBIT('q', "quiet", &options.flags,
			   N_("be quiet. implies --no-stat"),
			   REBASE_NO_QUIET| REBASE_VERBOSE | REBASE_DIFFSTAT),
		OPT_BIT('v', "verbose", &options.flags,
			N_("display a diffstat of what changed upstream"),
			REBASE_NO_QUIET | REBASE_VERBOSE | REBASE_DIFFSTAT),
		{OPTION_NEGBIT, 'n', "no-stat", &options.flags, NULL,
			N_("do not show diffstat of what changed upstream"),
			PARSE_OPT_NOARG, NULL, REBASE_DIFFSTAT },
		OPT_END(),
	};

	/*
	 * NEEDSWORK: Once the builtin rebase has been tested enough
	 * and git-legacy-rebase.sh is retired to contrib/, this preamble
	 * can be removed.
	 */

	if (!use_builtin_rebase()) {
		const char *path = mkpath("%s/git-legacy-rebase",
					  git_exec_path());

		if (sane_execvp(path, (char **)argv) < 0)
			die_errno(_("could not exec %s"), path);
		else
			BUG("sane_execvp() returned???");
	}

	if (argc == 2 && !strcmp(argv[1], "-h"))
		usage_with_options(builtin_rebase_usage,
				   builtin_rebase_options);

	prefix = setup_git_directory();
	trace_repo_setup(prefix);
	setup_work_tree();

	git_config(rebase_config, &options);

	argc = parse_options(argc, argv, prefix,
			     builtin_rebase_options,
			     builtin_rebase_usage, 0);

	if (argc > 2)
		usage_with_options(builtin_rebase_usage,
				   builtin_rebase_options);

	if (!(options.flags & REBASE_NO_QUIET))
		strbuf_addstr(&options.git_am_opt, " -q");

	switch (options.type) {
	case REBASE_MERGE:
	case REBASE_INTERACTIVE:
	case REBASE_PRESERVE_MERGES:
		options.state_dir = merge_dir();
		break;
	case REBASE_AM:
		options.state_dir = apply_dir();
		break;
	default:
		/* the default rebase backend is `--am` */
		options.type = REBASE_AM;
		options.state_dir = apply_dir();
		break;
	}

	if (!options.root) {
		if (argc < 1)
			die("TODO: handle @{upstream}");
		else {
			options.upstream_name = argv[0];
			argc--;
			argv++;
			if (!strcmp(options.upstream_name, "-"))
				options.upstream_name = "@{-1}";
		}
		options.upstream = peel_committish(options.upstream_name);
		if (!options.upstream)
			die(_("invalid upstream '%s'"), options.upstream_name);
		options.upstream_arg = options.upstream_name;
	} else
		die("TODO: upstream for --root");

	/* Make sure the branch to rebase onto is valid. */
	if (!options.onto_name)
		options.onto_name = options.upstream_name;
	if (strstr(options.onto_name, "...")) {
		if (get_oid_mb(options.onto_name, &merge_base) < 0)
			die(_("'%s': need exactly one merge base"),
			    options.onto_name);
		options.onto = lookup_commit_or_die(&merge_base,
						    options.onto_name);
	} else {
		options.onto = peel_committish(options.onto_name);
		if (!options.onto)
			die(_("Does not point to a valid commit '%s'"),
				options.onto_name);
	}

	/*
	 * If the branch to rebase is given, that is the branch we will rebase
	 * branch_name -- branch/commit being rebased, or
	 * 		  HEAD (already detached)
	 * orig_head -- commit object name of tip of the branch before rebasing
	 * head_name -- refs/heads/<that-branch> or "detached HEAD"
	 */
	if (argc > 0)
		 die("TODO: handle switch_to");
	else {
		/* Do not need to switch branches, we are already on it. */
		options.head_name =
			xstrdup_or_null(resolve_ref_unsafe("HEAD", 0, NULL,
					 &flags));
		if (!options.head_name)
			die(_("No such ref: %s"), "HEAD");
		if (flags & REF_ISSYMREF) {
			if (!skip_prefix(options.head_name,
					 "refs/heads/", &branch_name))
				branch_name = options.head_name;

		} else {
			options.head_name = xstrdup("detached HEAD");
			branch_name = "HEAD";
		}
		if (get_oid("HEAD", &options.orig_head))
			die(_("Could not resolve HEAD to a revision"));
	}

	if (read_index(the_repository->index) < 0)
		die(_("could not read index"));

	if (require_clean_work_tree("rebase",
				    _("Please commit or stash them."), 1, 1)) {
		ret = 1;
		goto cleanup;
	}

	/* If a hook exists, give it a chance to interrupt*/
	if (!ok_to_skip_pre_rebase &&
	    run_hook_le(NULL, "pre-rebase", options.upstream_arg,
			argc ? argv[0] : NULL, NULL))
		die(_("The pre-rebase hook refused to rebase."));

	if (options.flags & REBASE_DIFFSTAT) {
		struct diff_options opts;

		if (options.flags & REBASE_VERBOSE)
			printf(_("Changes from %s to %s:\n"),
				oid_to_hex(&merge_base),
				oid_to_hex(&options.onto->object.oid));

		/* We want color (if set), but no pager */
		diff_setup(&opts);
		opts.stat_width = -1; /* use full terminal width */
		opts.stat_graph_width = -1; /* respect statGraphWidth config */
		opts.output_format |=
			DIFF_FORMAT_SUMMARY | DIFF_FORMAT_DIFFSTAT;
		opts.detect_rename = DIFF_DETECT_RENAME;
		diff_setup_done(&opts);
		diff_tree_oid(&merge_base, &options.onto->object.oid,
			      "", &opts);
		diffcore_std(&opts);
		diff_flush(&opts);
	}

	/* Detach HEAD and reset the tree */
	if (options.flags & REBASE_NO_QUIET)
		printf(_("First, rewinding head to replay your work on top of "
			 "it...\n"));

	strbuf_addf(&msg, "rebase: checkout %s", options.onto_name);
	if (reset_head(&options.onto->object.oid, "checkout", NULL, 1))
		die(_("Could not detach HEAD"));
	strbuf_release(&msg);

	strbuf_addf(&revisions, "%s..%s",
		    options.root ? oid_to_hex(&options.onto->object.oid) :
		    (options.restrict_revision ?
		     oid_to_hex(&options.restrict_revision->object.oid) :
		     oid_to_hex(&options.upstream->object.oid)),
		    oid_to_hex(&options.orig_head));

	options.revisions = revisions.buf;

	ret = !!run_specific_rebase(&options);

cleanup:
	strbuf_release(&revisions);
	free(options.head_name);
	return ret;
}
Commit	Line	Data
55071ea2 PK	1	/*
	2	* "git rebase" builtin command
	3	*
	4	* Copyright (c) 2018 Pratik Karki
	5	*/
	6
	7	#include "builtin.h"
	8	#include "run-command.h"
	9	#include "exec-cmd.h"
	10	#include "argv-array.h"
	11	#include "dir.h"
ac7f467f PK	12	#include "packfile.h"
	13	#include "refs.h"
	14	#include "quote.h"
	15	#include "config.h"
	16	#include "cache-tree.h"
	17	#include "unpack-trees.h"
	18	#include "lockfile.h"
f28d40d3	19	#include "parse-options.h"
075bc852	20	#include "commit.h"
bff014da	21	#include "diff.h"
e0333e5c	22	#include "wt-status.h"
f28d40d3 PK	23
	24	static char const * const builtin_rebase_usage[] = {
	25	N_("git rebase [-i] [options] [--exec <cmd>] [--onto <newbase>] "
	26	"[<upstream>] [<branch>]"),
	27	N_("git rebase [-i] [options] [--exec <cmd>] [--onto <newbase>] "
	28	"--root [<branch>]"),
	29	N_("git rebase --continue \| --abort \| --skip \| --edit-todo"),
	30	NULL
	31	};
ac7f467f PK	32
	33	static GIT_PATH_FUNC(apply_dir, "rebase-apply")
	34	static GIT_PATH_FUNC(merge_dir, "rebase-merge")
	35
	36	enum rebase_type {
	37	REBASE_UNSPECIFIED = -1,
	38	REBASE_AM,
	39	REBASE_MERGE,
	40	REBASE_INTERACTIVE,
	41	REBASE_PRESERVE_MERGES
	42	};
55071ea2 PK	43
	44	static int use_builtin_rebase(void)
	45	{
	46	struct child_process cp = CHILD_PROCESS_INIT;
	47	struct strbuf out = STRBUF_INIT;
	48	int ret;
	49
	50	argv_array_pushl(&cp.args,
	51	"config", "--bool", "rebase.usebuiltin", NULL);
	52	cp.git_cmd = 1;
	53	if (capture_command(&cp, &out, 6)) {
	54	strbuf_release(&out);
	55	return 0;
	56	}
	57
	58	strbuf_trim(&out);
	59	ret = !strcmp("true", out.buf);
	60	strbuf_release(&out);
	61	return ret;
	62	}
	63
ac7f467f PK	64	static int apply_autostash(void)
	65	{
	66	warning("TODO");
	67	return 0;
	68	}
	69
	70	struct rebase_options {
	71	enum rebase_type type;
	72	const char *state_dir;
	73	struct commit *upstream;
	74	const char *upstream_name;
06e4775a	75	const char *upstream_arg;
ac7f467f PK	76	char *head_name;
	77	struct object_id orig_head;
	78	struct commit *onto;
	79	const char *onto_name;
	80	const char *revisions;
	81	int root;
	82	struct commit *restrict_revision;
	83	int dont_finish_rebase;
b4c8eb02 PK	84	enum {
b4c8eb02 PK	85	REBASE_NO_QUIET = 1<<0,
bff014da PK	86	REBASE_VERBOSE = 1<<1,
bff014da PK	87	REBASE_DIFFSTAT = 1<<2,
b4c8eb02 PK	88	} flags;
b4c8eb02 PK	89	struct strbuf git_am_opt;
ac7f467f PK	90	};
	91
	92	/* Returns the filename prefixed by the state_dir */
	93	static const char state_dir_path(const char filename, struct rebase_options *opts)
	94	{
	95	static struct strbuf path = STRBUF_INIT;
	96	static size_t prefix_len;
	97
	98	if (!prefix_len) {
	99	strbuf_addf(&path, "%s/", opts->state_dir);
	100	prefix_len = path.len;
	101	}
	102
	103	strbuf_setlen(&path, prefix_len);
	104	strbuf_addstr(&path, filename);
	105	return path.buf;
	106	}
	107
	108	static int finish_rebase(struct rebase_options *opts)
	109	{
	110	struct strbuf dir = STRBUF_INIT;
	111	const char *argv_gc_auto[] = { "gc", "--auto", NULL };
	112
	113	delete_ref(NULL, "REBASE_HEAD", NULL, REF_NO_DEREF);
	114	apply_autostash();
	115	close_all_packs(the_repository->objects);
	116	/*
	117	* We ignore errors in 'gc --auto', since the
	118	* user should see them.
	119	*/
	120	run_command_v_opt(argv_gc_auto, RUN_GIT_CMD);
	121	strbuf_addstr(&dir, opts->state_dir);
	122	remove_dir_recursively(&dir, 0);
	123	strbuf_release(&dir);
	124
	125	return 0;
	126	}
	127
	128	static struct commit peel_committish(const char name)
	129	{
	130	struct object *obj;
	131	struct object_id oid;
	132
	133	if (get_oid(name, &oid))
	134	return NULL;
	135	obj = parse_object(the_repository, &oid);
	136	return (struct commit *)peel_to_type(name, 0, obj, OBJ_COMMIT);
	137	}
	138
	139	static void add_var(struct strbuf buf, const char name, const char *value)
	140	{
	141	if (!value)
	142	strbuf_addf(buf, "unset %s; ", name);
	143	else {
	144	strbuf_addf(buf, "%s=", name);
	145	sq_quote_buf(buf, value);
	146	strbuf_addstr(buf, "; ");
	147	}
	148	}
	149
	150	static int run_specific_rebase(struct rebase_options *opts)
	151	{
	152	const char *argv[] = { NULL, NULL };
	153	struct strbuf script_snippet = STRBUF_INIT;
154	int status;
155	const char backend, backend_func;
156
157	add_var(&script_snippet, "GIT_DIR", absolute_path(get_git_dir()));
158	add_var(&script_snippet, "state_dir", opts->state_dir);
159
160	add_var(&script_snippet, "upstream_name", opts->upstream_name);
161	add_var(&script_snippet, "upstream",
162	oid_to_hex(&opts->upstream->object.oid));
163	add_var(&script_snippet, "head_name", opts->head_name);
164	add_var(&script_snippet, "orig_head", oid_to_hex(&opts->orig_head));
165	add_var(&script_snippet, "onto", oid_to_hex(&opts->onto->object.oid));
166	add_var(&script_snippet, "onto_name", opts->onto_name);
167	add_var(&script_snippet, "revisions", opts->revisions);
168	add_var(&script_snippet, "restrict_revision", opts->restrict_revision ?
169	oid_to_hex(&opts->restrict_revision->object.oid) : NULL);
b4c8eb02 PK	170	add_var(&script_snippet, "GIT_QUIET",
	171	opts->flags & REBASE_NO_QUIET ? "" : "t");
	172	add_var(&script_snippet, "git_am_opt", opts->git_am_opt.buf);
bff014da PK	173	add_var(&script_snippet, "verbose",
	174	opts->flags & REBASE_VERBOSE ? "t" : "");
	175	add_var(&script_snippet, "diffstat",
	176	opts->flags & REBASE_DIFFSTAT ? "t" : "");
ac7f467f PK	177
	178	switch (opts->type) {
	179	case REBASE_AM:
	180	backend = "git-rebase--am";
	181	backend_func = "git_rebase__am";
	182	break;
	183	case REBASE_INTERACTIVE:
	184	backend = "git-rebase--interactive";
	185	backend_func = "git_rebase__interactive";
	186	break;
	187	case REBASE_MERGE:
	188	backend = "git-rebase--merge";
	189	backend_func = "git_rebase__merge";
	190	break;
	191	case REBASE_PRESERVE_MERGES:
	192	backend = "git-rebase--preserve-merges";
	193	backend_func = "git_rebase__preserve_merges";
	194	break;
	195	default:
	196	BUG("Unhandled rebase type %d", opts->type);
	197	break;
	198	}
	199
	200	strbuf_addf(&script_snippet,
	201	". git-sh-setup && . git-rebase--common &&"
	202	" . %s && %s", backend, backend_func);
	203	argv[0] = script_snippet.buf;
	204
	205	status = run_command_v_opt(argv, RUN_USING_SHELL);
	206	if (opts->dont_finish_rebase)
	207	; /* do nothing */
	208	else if (status == 0) {
	209	if (!file_exists(state_dir_path("stopped-sha", opts)))
	210	finish_rebase(opts);
	211	} else if (status == 2) {
	212	struct strbuf dir = STRBUF_INIT;
	213
	214	apply_autostash();
	215	strbuf_addstr(&dir, opts->state_dir);
	216	remove_dir_recursively(&dir, 0);
	217	strbuf_release(&dir);
	218	die("Nothing to do");
	219	}
	220
	221	strbuf_release(&script_snippet);
	222
	223	return status ? -1 : 0;
	224	}
	225
	226	#define GIT_REFLOG_ACTION_ENVIRONMENT "GIT_REFLOG_ACTION"
	227
	228	static int reset_head(struct object_id oid, const char action,
	229	const char *switch_to_branch, int detach_head)
	230	{
	231	struct object_id head_oid;
	232	struct tree_desc desc;
	233	struct lock_file lock = LOCK_INIT;
	234	struct unpack_trees_options unpack_tree_opts;
	235	struct tree *tree;
	236	const char *reflog_action;
	237	struct strbuf msg = STRBUF_INIT;
	238	size_t prefix_len;
	239	struct object_id *orig = NULL, oid_orig,
	240	*old_orig = NULL, oid_old_orig;
241	int ret = 0;
242
243	if (hold_locked_index(&lock, LOCK_REPORT_ON_ERROR) < 0)
244	return -1;
245
246	if (!oid) {
247	if (get_oid("HEAD", &head_oid)) {
248	rollback_lock_file(&lock);
249	return error(_("could not determine HEAD revision"));
250	}
251	oid = &head_oid;
252	}
253
254	memset(&unpack_tree_opts, 0, sizeof(unpack_tree_opts));
255	setup_unpack_trees_porcelain(&unpack_tree_opts, action);
256	unpack_tree_opts.head_idx = 1;
257	unpack_tree_opts.src_index = the_repository->index;
258	unpack_tree_opts.dst_index = the_repository->index;
259	unpack_tree_opts.fn = oneway_merge;
260	unpack_tree_opts.update = 1;
261	unpack_tree_opts.merge = 1;
262	if (!detach_head)
263	unpack_tree_opts.reset = 1;
264
265	if (read_index_unmerged(the_repository->index) < 0) {
266	rollback_lock_file(&lock);
267	return error(_("could not read index"));
268	}
269
270	if (!fill_tree_descriptor(&desc, oid)) {
271	error(_("failed to find tree of %s"), oid_to_hex(oid));
272	rollback_lock_file(&lock);
273	free((void *)desc.buffer);
274	return -1;
275	}
276
277	if (unpack_trees(1, &desc, &unpack_tree_opts)) {
278	rollback_lock_file(&lock);
279	free((void *)desc.buffer);
280	return -1;
281	}
282
283	tree = parse_tree_indirect(oid);
284	prime_cache_tree(the_repository->index, tree);
285
286	if (write_locked_index(the_repository->index, &lock, COMMIT_LOCK) < 0)
287	ret = error(_("could not write index"));
288	free((void *)desc.buffer);
289
290	if (ret)
291	return ret;
292
293	reflog_action = getenv(GIT_REFLOG_ACTION_ENVIRONMENT);
294	strbuf_addf(&msg, "%s: ", reflog_action ? reflog_action : "rebase");
295	prefix_len = msg.len;
296
297	if (!get_oid("ORIG_HEAD", &oid_old_orig))
298	old_orig = &oid_old_orig;
299	if (!get_oid("HEAD", &oid_orig)) {
300	orig = &oid_orig;
301	strbuf_addstr(&msg, "updating ORIG_HEAD");
302	update_ref(msg.buf, "ORIG_HEAD", orig, old_orig, 0,
303	UPDATE_REFS_MSG_ON_ERR);
304	} else if (old_orig)
305	delete_ref(NULL, "ORIG_HEAD", old_orig, 0);
306	strbuf_setlen(&msg, prefix_len);
307	strbuf_addstr(&msg, "updating HEAD");
308	if (!switch_to_branch)
309	ret = update_ref(msg.buf, "HEAD", oid, orig, REF_NO_DEREF,
310	UPDATE_REFS_MSG_ON_ERR);
311	else {
312	ret = create_symref("HEAD", switch_to_branch, msg.buf);
313	if (!ret)
314	ret = update_ref(msg.buf, "HEAD", oid, NULL, 0,
315	UPDATE_REFS_MSG_ON_ERR);
316	}
317
318	strbuf_release(&msg);
319	return ret;
320	}
321
bff014da PK	322	static int rebase_config(const char var, const char value, void *data)
	323	{
	324	struct rebase_options *opts = data;
	325
	326	if (!strcmp(var, "rebase.stat")) {
	327	if (git_config_bool(var, value))
	328	opts->flags \|= REBASE_DIFFSTAT;
	329	else
	330	opts->flags &= !REBASE_DIFFSTAT;
	331	return 0;
	332	}
	333
	334	return git_default_config(var, value, data);
	335	}
	336
55071ea2 PK	337	int cmd_rebase(int argc, const char *argv, const char prefix)
55071ea2 PK	338	{
ac7f467f PK	339	struct rebase_options options = {
ac7f467f PK	340	.type = REBASE_UNSPECIFIED,
b4c8eb02 PK	341	.flags = REBASE_NO_QUIET,
b4c8eb02 PK	342	.git_am_opt = STRBUF_INIT,
ac7f467f PK	343	};
	344	const char *branch_name;
	345	int ret, flags;
06e4775a	346	int ok_to_skip_pre_rebase = 0;
ac7f467f PK	347	struct strbuf msg = STRBUF_INIT;
ac7f467f PK	348	struct strbuf revisions = STRBUF_INIT;
075bc852	349	struct object_id merge_base;
f28d40d3 PK	350	struct option builtin_rebase_options[] = {
	351	OPT_STRING(0, "onto", &options.onto_name,
	352	N_("revision"),
	353	N_("rebase onto given branch instead of upstream")),
06e4775a PK	354	OPT_BOOL(0, "no-verify", &ok_to_skip_pre_rebase,
06e4775a PK	355	N_("allow pre-rebase hook to run")),
b4c8eb02 PK	356	OPT_NEGBIT('q', "quiet", &options.flags,
b4c8eb02 PK	357	N_("be quiet. implies --no-stat"),
bff014da PK	358	REBASE_NO_QUIET\| REBASE_VERBOSE \| REBASE_DIFFSTAT),
	359	OPT_BIT('v', "verbose", &options.flags,
	360	N_("display a diffstat of what changed upstream"),
	361	REBASE_NO_QUIET \| REBASE_VERBOSE \| REBASE_DIFFSTAT),
	362	{OPTION_NEGBIT, 'n', "no-stat", &options.flags, NULL,
	363	N_("do not show diffstat of what changed upstream"),
	364	PARSE_OPT_NOARG, NULL, REBASE_DIFFSTAT },
f28d40d3 PK	365	OPT_END(),
f28d40d3 PK	366	};
ac7f467f	367
55071ea2 PK	368	/*
	369	* NEEDSWORK: Once the builtin rebase has been tested enough
	370	* and git-legacy-rebase.sh is retired to contrib/, this preamble
	371	* can be removed.
	372	*/
	373
	374	if (!use_builtin_rebase()) {
	375	const char *path = mkpath("%s/git-legacy-rebase",
	376	git_exec_path());
	377
	378	if (sane_execvp(path, (char **)argv) < 0)
	379	die_errno(_("could not exec %s"), path);
	380	else
	381	BUG("sane_execvp() returned???");
	382	}
	383
f28d40d3 PK	384	if (argc == 2 && !strcmp(argv[1], "-h"))
	385	usage_with_options(builtin_rebase_usage,
	386	builtin_rebase_options);
	387
55071ea2 PK	388	prefix = setup_git_directory();
	389	trace_repo_setup(prefix);
	390	setup_work_tree();
	391
bff014da PK	392	git_config(rebase_config, &options);
bff014da PK	393
f28d40d3 PK	394	argc = parse_options(argc, argv, prefix,
	395	builtin_rebase_options,
	396	builtin_rebase_usage, 0);
	397
	398	if (argc > 2)
	399	usage_with_options(builtin_rebase_usage,
	400	builtin_rebase_options);
ac7f467f	401
b4c8eb02 PK	402	if (!(options.flags & REBASE_NO_QUIET))
	403	strbuf_addstr(&options.git_am_opt, " -q");
	404
ac7f467f PK	405	switch (options.type) {
	406	case REBASE_MERGE:
	407	case REBASE_INTERACTIVE:
	408	case REBASE_PRESERVE_MERGES:
	409	options.state_dir = merge_dir();
	410	break;
	411	case REBASE_AM:
	412	options.state_dir = apply_dir();
	413	break;
	414	default:
	415	/* the default rebase backend is `--am` */
	416	options.type = REBASE_AM;
	417	options.state_dir = apply_dir();
	418	break;
	419	}
	420
	421	if (!options.root) {
f28d40d3	422	if (argc < 1)
ac7f467f PK	423	die("TODO: handle @{upstream}");
ac7f467f PK	424	else {
f28d40d3	425	options.upstream_name = argv[0];
ac7f467f PK	426	argc--;
	427	argv++;
	428	if (!strcmp(options.upstream_name, "-"))
	429	options.upstream_name = "@{-1}";
	430	}
	431	options.upstream = peel_committish(options.upstream_name);
	432	if (!options.upstream)
	433	die(_("invalid upstream '%s'"), options.upstream_name);
06e4775a	434	options.upstream_arg = options.upstream_name;
ac7f467f PK	435	} else
	436	die("TODO: upstream for --root");
	437
	438	/* Make sure the branch to rebase onto is valid. */
	439	if (!options.onto_name)
	440	options.onto_name = options.upstream_name;
	441	if (strstr(options.onto_name, "...")) {
075bc852 PK	442	if (get_oid_mb(options.onto_name, &merge_base) < 0)
	443	die(_("'%s': need exactly one merge base"),
	444	options.onto_name);
	445	options.onto = lookup_commit_or_die(&merge_base,
	446	options.onto_name);
ac7f467f PK	447	} else {
	448	options.onto = peel_committish(options.onto_name);
	449	if (!options.onto)
	450	die(_("Does not point to a valid commit '%s'"),
	451	options.onto_name);
	452	}
	453
	454	/*
	455	* If the branch to rebase is given, that is the branch we will rebase
	456	* branch_name -- branch/commit being rebased, or
	457	* HEAD (already detached)
	458	* orig_head -- commit object name of tip of the branch before rebasing
	459	* head_name -- refs/heads/<that-branch> or "detached HEAD"
	460	*/
f28d40d3	461	if (argc > 0)
ac7f467f PK	462	die("TODO: handle switch_to");
	463	else {
	464	/* Do not need to switch branches, we are already on it. */
	465	options.head_name =
	466	xstrdup_or_null(resolve_ref_unsafe("HEAD", 0, NULL,
	467	&flags));
	468	if (!options.head_name)
	469	die(_("No such ref: %s"), "HEAD");
	470	if (flags & REF_ISSYMREF) {
	471	if (!skip_prefix(options.head_name,
	472	"refs/heads/", &branch_name))
	473	branch_name = options.head_name;
	474
	475	} else {
	476	options.head_name = xstrdup("detached HEAD");
	477	branch_name = "HEAD";
	478	}
	479	if (get_oid("HEAD", &options.orig_head))
	480	die(_("Could not resolve HEAD to a revision"));
	481	}
	482
e0333e5c PK	483	if (read_index(the_repository->index) < 0)
	484	die(_("could not read index"));
	485
	486	if (require_clean_work_tree("rebase",
	487	_("Please commit or stash them."), 1, 1)) {
	488	ret = 1;
	489	goto cleanup;
	490	}
	491
06e4775a PK	492	/* If a hook exists, give it a chance to interrupt*/
	493	if (!ok_to_skip_pre_rebase &&
	494	run_hook_le(NULL, "pre-rebase", options.upstream_arg,
	495	argc ? argv[0] : NULL, NULL))
	496	die(_("The pre-rebase hook refused to rebase."));
	497
bff014da PK	498	if (options.flags & REBASE_DIFFSTAT) {
	499	struct diff_options opts;
	500
	501	if (options.flags & REBASE_VERBOSE)
	502	printf(_("Changes from %s to %s:\n"),
	503	oid_to_hex(&merge_base),
	504	oid_to_hex(&options.onto->object.oid));
	505
	506	/* We want color (if set), but no pager */
	507	diff_setup(&opts);
	508	opts.stat_width = -1; /* use full terminal width */
	509	opts.stat_graph_width = -1; /* respect statGraphWidth config */
	510	opts.output_format \|=
	511	DIFF_FORMAT_SUMMARY \| DIFF_FORMAT_DIFFSTAT;
	512	opts.detect_rename = DIFF_DETECT_RENAME;
	513	diff_setup_done(&opts);
	514	diff_tree_oid(&merge_base, &options.onto->object.oid,
	515	"", &opts);
	516	diffcore_std(&opts);
	517	diff_flush(&opts);
	518	}
	519
	520	/* Detach HEAD and reset the tree */
	521	if (options.flags & REBASE_NO_QUIET)
	522	printf(_("First, rewinding head to replay your work on top of "
	523	"it...\n"));
	524
ac7f467f PK	525	strbuf_addf(&msg, "rebase: checkout %s", options.onto_name);
	526	if (reset_head(&options.onto->object.oid, "checkout", NULL, 1))
	527	die(_("Could not detach HEAD"));
	528	strbuf_release(&msg);
	529
	530	strbuf_addf(&revisions, "%s..%s",
	531	options.root ? oid_to_hex(&options.onto->object.oid) :
	532	(options.restrict_revision ?
	533	oid_to_hex(&options.restrict_revision->object.oid) :
	534	oid_to_hex(&options.upstream->object.oid)),
	535	oid_to_hex(&options.orig_head));
	536
	537	options.revisions = revisions.buf;
	538
	539	ret = !!run_specific_rebase(&options);
	540
e0333e5c	541	cleanup:
ac7f467f PK	542	strbuf_release(&revisions);
	543	free(options.head_name);
	544	return ret;
55071ea2	545	}