[thirdparty/git.git] / ll-merge.c

/*
 * Low level 3-way in-core file merge.
 *
 * Copyright (c) 2007 Junio C Hamano
 */

#include "cache.h"
#include "attr.h"
#include "xdiff-interface.h"
#include "run-command.h"
#include "ll-merge.h"

struct ll_merge_driver;

typedef int (*ll_merge_fn)(const struct ll_merge_driver *,
			   mmbuffer_t *result,
			   const char *path,
			   mmfile_t *orig, const char *orig_name,
			   mmfile_t *src1, const char *name1,
			   mmfile_t *src2, const char *name2,
			   int flag,
			   int marker_size);

struct ll_merge_driver {
	const char *name;
	const char *description;
	ll_merge_fn fn;
	const char *recursive;
	struct ll_merge_driver *next;
	char *cmdline;
};

/*
 * Built-in low-levels
 */
static int ll_binary_merge(const struct ll_merge_driver *drv_unused,
			   mmbuffer_t *result,
			   const char *path_unused,
			   mmfile_t *orig, const char *orig_name,
			   mmfile_t *src1, const char *name1,
			   mmfile_t *src2, const char *name2,
			   int flag, int marker_size)
{
	/*
	 * The tentative merge result is "ours" for the final round,
	 * or common ancestor for an internal merge.  Still return
	 * "conflicted merge" status.
	 */
	mmfile_t *stolen = (flag & LL_OPT_VIRTUAL_ANCESTOR) ? orig : src1;

	result->ptr = stolen->ptr;
	result->size = stolen->size;
	stolen->ptr = NULL;
	return 1;
}

static int ll_xdl_merge(const struct ll_merge_driver *drv_unused,
			mmbuffer_t *result,
			const char *path,
			mmfile_t *orig, const char *orig_name,
			mmfile_t *src1, const char *name1,
			mmfile_t *src2, const char *name2,
			int flag, int marker_size)
{
	xmparam_t xmp;

	if (buffer_is_binary(orig->ptr, orig->size) ||
	    buffer_is_binary(src1->ptr, src1->size) ||
	    buffer_is_binary(src2->ptr, src2->size)) {
		warning("Cannot merge binary files: %s (%s vs. %s)\n",
			path, name1, name2);
		return ll_binary_merge(drv_unused, result,
				       path,
				       orig, orig_name,
				       src1, name1,
				       src2, name2,
				       flag, marker_size);
	}

	memset(&xmp, 0, sizeof(xmp));
	xmp.level = XDL_MERGE_ZEALOUS;
	xmp.favor = ll_opt_favor(flag);
	if (git_xmerge_style >= 0)
		xmp.style = git_xmerge_style;
	if (marker_size > 0)
		xmp.marker_size = marker_size;
	xmp.ancestor = orig_name;
	xmp.file1 = name1;
	xmp.file2 = name2;
	return xdl_merge(orig, src1, src2, &xmp, result);
}

static int ll_union_merge(const struct ll_merge_driver *drv_unused,
			  mmbuffer_t *result,
			  const char *path_unused,
			  mmfile_t *orig, const char *orig_name,
			  mmfile_t *src1, const char *name1,
			  mmfile_t *src2, const char *name2,
			  int flag, int marker_size)
{
	/* Use union favor */
	flag &= ~LL_OPT_FAVOR_MASK;
	flag |= create_ll_flag(XDL_MERGE_FAVOR_UNION);
	return ll_xdl_merge(drv_unused, result, path_unused,
			    orig, NULL, src1, NULL, src2, NULL,
			    flag, marker_size);
	return 0;
}

#define LL_BINARY_MERGE 0
#define LL_TEXT_MERGE 1
#define LL_UNION_MERGE 2
static struct ll_merge_driver ll_merge_drv[] = {
	{ "binary", "built-in binary merge", ll_binary_merge },
	{ "text", "built-in 3-way text merge", ll_xdl_merge },
	{ "union", "built-in union merge", ll_union_merge },
};

static void create_temp(mmfile_t *src, char *path)
{
	int fd;

	strcpy(path, ".merge_file_XXXXXX");
	fd = xmkstemp(path);
	if (write_in_full(fd, src->ptr, src->size) != src->size)
		die_errno("unable to write temp-file");
	close(fd);
}

/*
 * User defined low-level merge driver support.
 */
static int ll_ext_merge(const struct ll_merge_driver *fn,
			mmbuffer_t *result,
			const char *path,
			mmfile_t *orig, const char *orig_name,
			mmfile_t *src1, const char *name1,
			mmfile_t *src2, const char *name2,
			int flag, int marker_size)
{
	char temp[4][50];
	struct strbuf cmd = STRBUF_INIT;
	struct strbuf_expand_dict_entry dict[5];
	const char *args[] = { NULL, NULL };
	int status, fd, i;
	struct stat st;

	dict[0].placeholder = "O"; dict[0].value = temp[0];
	dict[1].placeholder = "A"; dict[1].value = temp[1];
	dict[2].placeholder = "B"; dict[2].value = temp[2];
	dict[3].placeholder = "L"; dict[3].value = temp[3];
	dict[4].placeholder = NULL; dict[4].value = NULL;

	if (fn->cmdline == NULL)
		die("custom merge driver %s lacks command line.", fn->name);

	result->ptr = NULL;
	result->size = 0;
	create_temp(orig, temp[0]);
	create_temp(src1, temp[1]);
	create_temp(src2, temp[2]);
	sprintf(temp[3], "%d", marker_size);

	strbuf_expand(&cmd, fn->cmdline, strbuf_expand_dict_cb, &dict);

	args[0] = cmd.buf;
	status = run_command_v_opt(args, RUN_USING_SHELL);
	fd = open(temp[1], O_RDONLY);
	if (fd < 0)
		goto bad;
	if (fstat(fd, &st))
		goto close_bad;
	result->size = st.st_size;
	result->ptr = xmalloc(result->size + 1);
	if (read_in_full(fd, result->ptr, result->size) != result->size) {
		free(result->ptr);
		result->ptr = NULL;
		result->size = 0;
	}
 close_bad:
	close(fd);
 bad:
	for (i = 0; i < 3; i++)
		unlink_or_warn(temp[i]);
	strbuf_release(&cmd);
	return status;
}

/*
 * merge.default and merge.driver configuration items
 */
static struct ll_merge_driver *ll_user_merge, **ll_user_merge_tail;
static const char *default_ll_merge;

static int read_merge_config(const char *var, const char *value, void *cb)
{
	struct ll_merge_driver *fn;
	const char *ep, *name;
	int namelen;

	if (!strcmp(var, "merge.default")) {
		if (value)
			default_ll_merge = xstrdup(value);
		return 0;
	}

	/*
	 * We are not interested in anything but "merge.<name>.variable";
	 * especially, we do not want to look at variables such as
	 * "merge.summary", "merge.tool", and "merge.verbosity".
	 */
	if (prefixcmp(var, "merge.") || (ep = strrchr(var, '.')) == var + 5)
		return 0;

	/*
	 * Find existing one as we might be processing merge.<name>.var2
	 * after seeing merge.<name>.var1.
	 */
	name = var + 6;
	namelen = ep - name;
	for (fn = ll_user_merge; fn; fn = fn->next)
		if (!strncmp(fn->name, name, namelen) && !fn->name[namelen])
			break;
	if (!fn) {
		fn = xcalloc(1, sizeof(struct ll_merge_driver));
		fn->name = xmemdupz(name, namelen);
		fn->fn = ll_ext_merge;
		*ll_user_merge_tail = fn;
		ll_user_merge_tail = &(fn->next);
	}

	ep++;

	if (!strcmp("name", ep)) {
		if (!value)
			return error("%s: lacks value", var);
		fn->description = xstrdup(value);
		return 0;
	}

	if (!strcmp("driver", ep)) {
		if (!value)
			return error("%s: lacks value", var);
		/*
		 * merge.<name>.driver specifies the command line:
		 *
		 *	command-line
		 *
		 * The command-line will be interpolated with the following
		 * tokens and is given to the shell:
		 *
		 *    %O - temporary file name for the merge base.
		 *    %A - temporary file name for our version.
		 *    %B - temporary file name for the other branches' version.
		 *    %L - conflict marker length
		 *
		 * The external merge driver should write the results in the
		 * file named by %A, and signal that it has done with zero exit
		 * status.
		 */
		fn->cmdline = xstrdup(value);
		return 0;
	}

	if (!strcmp("recursive", ep)) {
		if (!value)
			return error("%s: lacks value", var);
		fn->recursive = xstrdup(value);
		return 0;
	}

	return 0;
}

static void initialize_ll_merge(void)
{
	if (ll_user_merge_tail)
		return;
	ll_user_merge_tail = &ll_user_merge;
	git_config(read_merge_config, NULL);
}

static const struct ll_merge_driver *find_ll_merge_driver(const char *merge_attr)
{
	struct ll_merge_driver *fn;
	const char *name;
	int i;

	initialize_ll_merge();

	if (ATTR_TRUE(merge_attr))
		return &ll_merge_drv[LL_TEXT_MERGE];
	else if (ATTR_FALSE(merge_attr))
		return &ll_merge_drv[LL_BINARY_MERGE];
	else if (ATTR_UNSET(merge_attr)) {
		if (!default_ll_merge)
			return &ll_merge_drv[LL_TEXT_MERGE];
		else
			name = default_ll_merge;
	}
	else
		name = merge_attr;

	for (fn = ll_user_merge; fn; fn = fn->next)
		if (!strcmp(fn->name, name))
			return fn;

	for (i = 0; i < ARRAY_SIZE(ll_merge_drv); i++)
		if (!strcmp(ll_merge_drv[i].name, name))
			return &ll_merge_drv[i];

	/* default to the 3-way */
	return &ll_merge_drv[LL_TEXT_MERGE];
}

static int git_path_check_merge(const char *path, struct git_attr_check check[2])
{
	if (!check[0].attr) {
		check[0].attr = git_attr("merge");
		check[1].attr = git_attr("conflict-marker-size");
	}
	return git_checkattr(path, 2, check);
}

static void normalize_file(mmfile_t *mm, const char *path)
{
	struct strbuf strbuf = STRBUF_INIT;
	if (renormalize_buffer(path, mm->ptr, mm->size, &strbuf)) {
		free(mm->ptr);
		mm->size = strbuf.len;
		mm->ptr = strbuf_detach(&strbuf, NULL);
	}
}

int ll_merge(mmbuffer_t *result_buf,
	     const char *path,
	     mmfile_t *ancestor, const char *ancestor_label,
	     mmfile_t *ours, const char *our_label,
	     mmfile_t *theirs, const char *their_label,
	     int flag)
{
	static struct git_attr_check check[2];
	const char *ll_driver_name = NULL;
	int marker_size = DEFAULT_CONFLICT_MARKER_SIZE;
	const struct ll_merge_driver *driver;
	int virtual_ancestor = flag & LL_OPT_VIRTUAL_ANCESTOR;

	if (flag & LL_OPT_RENORMALIZE) {
		normalize_file(ancestor, path);
		normalize_file(ours, path);
		normalize_file(theirs, path);
	}
	if (!git_path_check_merge(path, check)) {
		ll_driver_name = check[0].value;
		if (check[1].value) {
			marker_size = atoi(check[1].value);
			if (marker_size <= 0)
				marker_size = DEFAULT_CONFLICT_MARKER_SIZE;
		}
	}
	driver = find_ll_merge_driver(ll_driver_name);
	if (virtual_ancestor && driver->recursive)
		driver = find_ll_merge_driver(driver->recursive);
	return driver->fn(driver, result_buf, path, ancestor, ancestor_label,
			  ours, our_label, theirs, their_label,
			  flag, marker_size);
}

int ll_merge_marker_size(const char *path)
{
	static struct git_attr_check check;
	int marker_size = DEFAULT_CONFLICT_MARKER_SIZE;

	if (!check.attr)
		check.attr = git_attr("conflict-marker-size");
	if (!git_checkattr(path, 1, &check) && check.value) {
		marker_size = atoi(check.value);
		if (marker_size <= 0)
			marker_size = DEFAULT_CONFLICT_MARKER_SIZE;
	}
	return marker_size;
}
Commit	Line	Data
525ab639 JH	1	/*
	2	* Low level 3-way in-core file merge.
	3	*
	4	* Copyright (c) 2007 Junio C Hamano
	5	*/
	6
	7	#include "cache.h"
	8	#include "attr.h"
	9	#include "xdiff-interface.h"
	10	#include "run-command.h"
525ab639 JH	11	#include "ll-merge.h"
	12
	13	struct ll_merge_driver;
	14
	15	typedef int (ll_merge_fn)(const struct ll_merge_driver ,
	16	mmbuffer_t *result,
	17	const char *path,
f01de62e	18	mmfile_t orig, const char orig_name,
525ab639 JH	19	mmfile_t src1, const char name1,
525ab639 JH	20	mmfile_t src2, const char name2,
06dbc1ea	21	int flag,
23a64c9e	22	int marker_size);
525ab639 JH	23
	24	struct ll_merge_driver {
	25	const char *name;
	26	const char *description;
	27	ll_merge_fn fn;
	28	const char *recursive;
	29	struct ll_merge_driver *next;
	30	char *cmdline;
	31	};
	32
	33	/*
	34	* Built-in low-levels
	35	*/
	36	static int ll_binary_merge(const struct ll_merge_driver *drv_unused,
	37	mmbuffer_t *result,
	38	const char *path_unused,
f01de62e	39	mmfile_t orig, const char orig_name,
525ab639 JH	40	mmfile_t src1, const char name1,
525ab639 JH	41	mmfile_t src2, const char name2,
06dbc1ea	42	int flag, int marker_size)
525ab639 JH	43	{
	44	/*
	45	* The tentative merge result is "ours" for the final round,
	46	* or common ancestor for an internal merge. Still return
	47	* "conflicted merge" status.
	48	*/
73cf7f71	49	mmfile_t *stolen = (flag & LL_OPT_VIRTUAL_ANCESTOR) ? orig : src1;
525ab639 JH	50
	51	result->ptr = stolen->ptr;
	52	result->size = stolen->size;
	53	stolen->ptr = NULL;
	54	return 1;
	55	}
	56
	57	static int ll_xdl_merge(const struct ll_merge_driver *drv_unused,
	58	mmbuffer_t *result,
606475f3	59	const char *path,
f01de62e	60	mmfile_t orig, const char orig_name,
525ab639 JH	61	mmfile_t src1, const char name1,
525ab639 JH	62	mmfile_t src2, const char name2,
06dbc1ea	63	int flag, int marker_size)
525ab639	64	{
00f8f97d	65	xmparam_t xmp;
525ab639 JH	66
	67	if (buffer_is_binary(orig->ptr, orig->size) \|\|
	68	buffer_is_binary(src1->ptr, src1->size) \|\|
	69	buffer_is_binary(src2->ptr, src2->size)) {
606475f3 MR	70	warning("Cannot merge binary files: %s (%s vs. %s)\n",
606475f3 MR	71	path, name1, name2);
525ab639	72	return ll_binary_merge(drv_unused, result,
606475f3	73	path,
f01de62e JN	74	orig, orig_name,
f01de62e JN	75	src1, name1,
525ab639	76	src2, name2,
06dbc1ea	77	flag, marker_size);
525ab639 JH	78	}
525ab639 JH	79
00f8f97d	80	memset(&xmp, 0, sizeof(xmp));
560119b9	81	xmp.level = XDL_MERGE_ZEALOUS;
73cf7f71	82	xmp.favor = ll_opt_favor(flag);
c236bcd0	83	if (git_xmerge_style >= 0)
560119b9	84	xmp.style = git_xmerge_style;
23a64c9e JH	85	if (marker_size > 0)
23a64c9e JH	86	xmp.marker_size = marker_size;
f01de62e	87	xmp.ancestor = orig_name;
a4b5e91c JN	88	xmp.file1 = name1;
	89	xmp.file2 = name2;
	90	return xdl_merge(orig, src1, src2, &xmp, result);
525ab639 JH	91	}
	92
	93	static int ll_union_merge(const struct ll_merge_driver *drv_unused,
	94	mmbuffer_t *result,
	95	const char *path_unused,
f01de62e	96	mmfile_t orig, const char orig_name,
525ab639 JH	97	mmfile_t src1, const char name1,
525ab639 JH	98	mmfile_t src2, const char name2,
06dbc1ea	99	int flag, int marker_size)
525ab639	100	{
cd1d61c4	101	/* Use union favor */
18b037a5 JN	102	flag &= ~LL_OPT_FAVOR_MASK;
18b037a5 JN	103	flag \|= create_ll_flag(XDL_MERGE_FAVOR_UNION);
cd1d61c4	104	return ll_xdl_merge(drv_unused, result, path_unused,
f01de62e	105	orig, NULL, src1, NULL, src2, NULL,
cd1d61c4	106	flag, marker_size);
525ab639 JH	107	return 0;
	108	}
	109
	110	#define LL_BINARY_MERGE 0
	111	#define LL_TEXT_MERGE 1
	112	#define LL_UNION_MERGE 2
	113	static struct ll_merge_driver ll_merge_drv[] = {
	114	{ "binary", "built-in binary merge", ll_binary_merge },
	115	{ "text", "built-in 3-way text merge", ll_xdl_merge },
	116	{ "union", "built-in union merge", ll_union_merge },
	117	};
	118
	119	static void create_temp(mmfile_t src, char path)
	120	{
	121	int fd;
	122
	123	strcpy(path, ".merge_file_XXXXXX");
	124	fd = xmkstemp(path);
	125	if (write_in_full(fd, src->ptr, src->size) != src->size)
0721c314	126	die_errno("unable to write temp-file");
525ab639 JH	127	close(fd);
	128	}
	129
	130	/*
	131	* User defined low-level merge driver support.
	132	*/
	133	static int ll_ext_merge(const struct ll_merge_driver *fn,
	134	mmbuffer_t *result,
	135	const char *path,
f01de62e	136	mmfile_t orig, const char orig_name,
525ab639 JH	137	mmfile_t src1, const char name1,
525ab639 JH	138	mmfile_t src2, const char name2,
06dbc1ea	139	int flag, int marker_size)
525ab639	140	{
23a64c9e	141	char temp[4][50];
ced621b2	142	struct strbuf cmd = STRBUF_INIT;
66dbfd55	143	struct strbuf_expand_dict_entry dict[5];
ac0ba18d	144	const char *args[] = { NULL, NULL };
525ab639 JH	145	int status, fd, i;
	146	struct stat st;
	147
66dbfd55 GV	148	dict[0].placeholder = "O"; dict[0].value = temp[0];
	149	dict[1].placeholder = "A"; dict[1].value = temp[1];
	150	dict[2].placeholder = "B"; dict[2].value = temp[2];
	151	dict[3].placeholder = "L"; dict[3].value = temp[3];
	152	dict[4].placeholder = NULL; dict[4].value = NULL;
	153
525ab639 JH	154	if (fn->cmdline == NULL)
	155	die("custom merge driver %s lacks command line.", fn->name);
	156
	157	result->ptr = NULL;
	158	result->size = 0;
	159	create_temp(orig, temp[0]);
	160	create_temp(src1, temp[1]);
	161	create_temp(src2, temp[2]);
23a64c9e	162	sprintf(temp[3], "%d", marker_size);
525ab639	163
ced621b2	164	strbuf_expand(&cmd, fn->cmdline, strbuf_expand_dict_cb, &dict);
525ab639	165
ac0ba18d JK	166	args[0] = cmd.buf;
ac0ba18d JK	167	status = run_command_v_opt(args, RUN_USING_SHELL);
525ab639 JH	168	fd = open(temp[1], O_RDONLY);
	169	if (fd < 0)
	170	goto bad;
	171	if (fstat(fd, &st))
	172	goto close_bad;
	173	result->size = st.st_size;
	174	result->ptr = xmalloc(result->size + 1);
	175	if (read_in_full(fd, result->ptr, result->size) != result->size) {
	176	free(result->ptr);
	177	result->ptr = NULL;
	178	result->size = 0;
	179	}
	180	close_bad:
	181	close(fd);
	182	bad:
	183	for (i = 0; i < 3; i++)
691f1a28	184	unlink_or_warn(temp[i]);
ced621b2	185	strbuf_release(&cmd);
525ab639 JH	186	return status;
	187	}
	188
	189	/*
	190	* merge.default and merge.driver configuration items
	191	*/
	192	static struct ll_merge_driver ll_user_merge, *ll_user_merge_tail;
	193	static const char *default_ll_merge;
	194
ef90d6d4	195	static int read_merge_config(const char var, const char value, void *cb)
525ab639 JH	196	{
	197	struct ll_merge_driver *fn;
	198	const char ep, name;
	199	int namelen;
	200
	201	if (!strcmp(var, "merge.default")) {
	202	if (value)
90dce515	203	default_ll_merge = xstrdup(value);
525ab639 JH	204	return 0;
	205	}
	206
	207	/*
	208	* We are not interested in anything but "merge.<name>.variable";
	209	* especially, we do not want to look at variables such as
	210	* "merge.summary", "merge.tool", and "merge.verbosity".
	211	*/
	212	if (prefixcmp(var, "merge.") \|\| (ep = strrchr(var, '.')) == var + 5)
	213	return 0;
	214
	215	/*
	216	* Find existing one as we might be processing merge.<name>.var2
	217	* after seeing merge.<name>.var1.
	218	*/
	219	name = var + 6;
	220	namelen = ep - name;
	221	for (fn = ll_user_merge; fn; fn = fn->next)
	222	if (!strncmp(fn->name, name, namelen) && !fn->name[namelen])
	223	break;
	224	if (!fn) {
	225	fn = xcalloc(1, sizeof(struct ll_merge_driver));
	226	fn->name = xmemdupz(name, namelen);
	227	fn->fn = ll_ext_merge;
	228	*ll_user_merge_tail = fn;
	229	ll_user_merge_tail = &(fn->next);
	230	}
	231
	232	ep++;
	233
	234	if (!strcmp("name", ep)) {
	235	if (!value)
	236	return error("%s: lacks value", var);
90dce515	237	fn->description = xstrdup(value);
525ab639 JH	238	return 0;
	239	}
	240
	241	if (!strcmp("driver", ep)) {
	242	if (!value)
	243	return error("%s: lacks value", var);
	244	/*
	245	* merge.<name>.driver specifies the command line:
	246	*
	247	* command-line
	248	*
	249	* The command-line will be interpolated with the following
	250	* tokens and is given to the shell:
	251	*
	252	* %O - temporary file name for the merge base.
	253	* %A - temporary file name for our version.
	254	* %B - temporary file name for the other branches' version.
23a64c9e	255	* %L - conflict marker length
525ab639 JH	256	*
	257	* The external merge driver should write the results in the
	258	* file named by %A, and signal that it has done with zero exit
	259	* status.
	260	*/
90dce515	261	fn->cmdline = xstrdup(value);
525ab639 JH	262	return 0;
	263	}
	264
	265	if (!strcmp("recursive", ep)) {
	266	if (!value)
	267	return error("%s: lacks value", var);
90dce515	268	fn->recursive = xstrdup(value);
525ab639 JH	269	return 0;
	270	}
	271
	272	return 0;
	273	}
	274
	275	static void initialize_ll_merge(void)
	276	{
	277	if (ll_user_merge_tail)
	278	return;
	279	ll_user_merge_tail = &ll_user_merge;
ef90d6d4	280	git_config(read_merge_config, NULL);
525ab639 JH	281	}
	282
	283	static const struct ll_merge_driver find_ll_merge_driver(const char merge_attr)
	284	{
	285	struct ll_merge_driver *fn;
	286	const char *name;
	287	int i;
	288
	289	initialize_ll_merge();
	290
	291	if (ATTR_TRUE(merge_attr))
	292	return &ll_merge_drv[LL_TEXT_MERGE];
	293	else if (ATTR_FALSE(merge_attr))
	294	return &ll_merge_drv[LL_BINARY_MERGE];
	295	else if (ATTR_UNSET(merge_attr)) {
	296	if (!default_ll_merge)
	297	return &ll_merge_drv[LL_TEXT_MERGE];
	298	else
	299	name = default_ll_merge;
	300	}
	301	else
	302	name = merge_attr;
	303
	304	for (fn = ll_user_merge; fn; fn = fn->next)
	305	if (!strcmp(fn->name, name))
	306	return fn;
	307
	308	for (i = 0; i < ARRAY_SIZE(ll_merge_drv); i++)
	309	if (!strcmp(ll_merge_drv[i].name, name))
	310	return &ll_merge_drv[i];
	311
	312	/* default to the 3-way */
	313	return &ll_merge_drv[LL_TEXT_MERGE];
	314	}
	315
23a64c9e	316	static int git_path_check_merge(const char *path, struct git_attr_check check[2])
525ab639	317	{
23a64c9e JH	318	if (!check[0].attr) {
	319	check[0].attr = git_attr("merge");
	320	check[1].attr = git_attr("conflict-marker-size");
	321	}
	322	return git_checkattr(path, 2, check);
525ab639 JH	323	}
525ab639 JH	324
f217f0e8 EB	325	static void normalize_file(mmfile_t mm, const char path)
	326	{
	327	struct strbuf strbuf = STRBUF_INIT;
	328	if (renormalize_buffer(path, mm->ptr, mm->size, &strbuf)) {
	329	free(mm->ptr);
	330	mm->size = strbuf.len;
	331	mm->ptr = strbuf_detach(&strbuf, NULL);
	332	}
	333	}
	334
525ab639 JH	335	int ll_merge(mmbuffer_t *result_buf,
525ab639 JH	336	const char *path,
f01de62e	337	mmfile_t ancestor, const char ancestor_label,
525ab639 JH	338	mmfile_t ours, const char our_label,
525ab639 JH	339	mmfile_t theirs, const char their_label,
8cc5b290	340	int flag)
525ab639	341	{
23a64c9e JH	342	static struct git_attr_check check[2];
	343	const char *ll_driver_name = NULL;
	344	int marker_size = DEFAULT_CONFLICT_MARKER_SIZE;
525ab639	345	const struct ll_merge_driver *driver;
73cf7f71	346	int virtual_ancestor = flag & LL_OPT_VIRTUAL_ANCESTOR;
525ab639	347
18b037a5	348	if (flag & LL_OPT_RENORMALIZE) {
f217f0e8 EB	349	normalize_file(ancestor, path);
	350	normalize_file(ours, path);
	351	normalize_file(theirs, path);
	352	}
23a64c9e JH	353	if (!git_path_check_merge(path, check)) {
	354	ll_driver_name = check[0].value;
	355	if (check[1].value) {
	356	marker_size = atoi(check[1].value);
	357	if (marker_size <= 0)
	358	marker_size = DEFAULT_CONFLICT_MARKER_SIZE;
	359	}
	360	}
525ab639	361	driver = find_ll_merge_driver(ll_driver_name);
525ab639 JH	362	if (virtual_ancestor && driver->recursive)
525ab639 JH	363	driver = find_ll_merge_driver(driver->recursive);
f01de62e	364	return driver->fn(driver, result_buf, path, ancestor, ancestor_label,
23a64c9e	365	ours, our_label, theirs, their_label,
06dbc1ea	366	flag, marker_size);
525ab639	367	}
8588567c JH	368
	369	int ll_merge_marker_size(const char *path)
	370	{
	371	static struct git_attr_check check;
	372	int marker_size = DEFAULT_CONFLICT_MARKER_SIZE;
	373
	374	if (!check.attr)
	375	check.attr = git_attr("conflict-marker-size");
	376	if (!git_checkattr(path, 1, &check) && check.value) {
	377	marker_size = atoi(check.value);
	378	if (marker_size <= 0)
	379	marker_size = DEFAULT_CONFLICT_MARKER_SIZE;
	380	}
	381	return marker_size;
525ab639	382	}