Merge branch 'jc/conflict-marker-size'

* jc/conflict-marker-size:
  rerere: honor conflict-marker-size attribute
  rerere: prepare for customizable conflict marker length
  conflict-marker-size: new attribute
  rerere: use ll_merge() instead of using xdl_merge()
  merge-tree: use ll_merge() not xdl_merge()
  xdl_merge(): allow passing down marker_size in xmparam_t
  xdl_merge(): introduce xmparam_t for merge specific parameters
  git_attr(): fix function signature

Conflicts:
	builtin-merge-file.c
	ll-merge.c
	xdiff/xdiff.h
	xdiff/xmerge.c

16 files changed, 155 insertions, 78 deletions

diff --git a/archive.c b/archive.c
index 5b88507374..d700af3b62 100644
--- a/archive.c
+++ b/archive.c
@@ -87,8 +87,8 @@ static void setup_archive_check(struct git_attr_check *check)
 	static struct git_attr *attr_export_subst;
 
 	if (!attr_export_ignore) {
-		attr_export_ignore = git_attr("export-ignore", 13);
-		attr_export_subst = git_attr("export-subst", 12);
+		attr_export_ignore = git_attr("export-ignore");
+		attr_export_subst = git_attr("export-subst");
 	}
 	check[0].attr = attr_export_ignore;
 	check[1].attr = attr_export_subst;
diff --git a/attr.c b/attr.c
index 55bdb7cdeb..f5346ed32a 100644
--- a/attr.c
+++ b/attr.c
@@ -65,7 +65,7 @@ static int invalid_attr_name(const char *name, int namelen)
 	return 0;
 }
 
-struct git_attr *git_attr(const char *name, int len)
+static struct git_attr *git_attr_internal(const char *name, int len)
 {
 	unsigned hval = hash_name(name, len);
 	unsigned pos = hval % HASHSIZE;
@@ -95,6 +95,11 @@ struct git_attr *git_attr(const char *name, int len)
 	return a;
 }
 
+struct git_attr *git_attr(const char *name)
+{
+	return git_attr_internal(name, strlen(name));
+}
+
 /*
  * .gitattributes file is one line per record, each of which is
  *
@@ -162,7 +167,7 @@ static const char *parse_attr(const char *src, int lineno, const char *cp,
 		else {
 			e->setto = xmemdupz(equals + 1, ep - equals - 1);
 		}
-		e->attr = git_attr(cp, len);
+		e->attr = git_attr_internal(cp, len);
 	}
 	(*num_attr)++;
 	return ep + strspn(ep, blank);
@@ -221,7 +226,7 @@ static struct match_attr *parse_attr_line(const char *line, const char *src,
 			      sizeof(struct attr_state) * num_attr +
 			      (is_macro ? 0 : namelen + 1));
 		if (is_macro)
-			res->u.attr = git_attr(name, namelen);
+			res->u.attr = git_attr_internal(name, namelen);
 		else {
 			res->u.pattern = (char *)&(res->state[num_attr]);
 			memcpy(res->u.pattern, name, namelen);
diff --git a/attr.h b/attr.h
index 69b5767ebc..450f49d648 100644
--- a/attr.h
+++ b/attr.h
@@ -8,7 +8,7 @@ struct git_attr;
  * Given a string, return the gitattribute object that
  * corresponds to it.
  */
-struct git_attr *git_attr(const char *, int);
+struct git_attr *git_attr(const char *);
 
 /* Internal use */
 extern const char git_attr__true[];
diff --git a/builtin-check-attr.c b/builtin-check-attr.c
index 8bd0430098..3016d29caa 100644
--- a/builtin-check-attr.c
+++ b/builtin-check-attr.c
@@ -106,7 +106,7 @@ int cmd_check_attr(int argc, const char **argv, const char *prefix)
 		const char *name;
 		struct git_attr *a;
 		name = argv[i];
-		a = git_attr(name, strlen(name));
+		a = git_attr(name);
 		if (!a)
 			return error("%s: not a valid attribute name", name);
 		check[i].attr = a;
diff --git a/builtin-merge-file.c b/builtin-merge-file.c
index 1efc4e09bc..1e70073a7e 100644
--- a/builtin-merge-file.c
+++ b/builtin-merge-file.c
@@ -25,7 +25,7 @@ int cmd_merge_file(int argc, const char **argv, const char *prefix)
 	const char *names[3] = { NULL, NULL, NULL };
 	mmfile_t mmfs[3];
 	mmbuffer_t result = {NULL, 0};
-	xpparam_t xpp = {XDF_NEED_MINIMAL};
+	xmparam_t xmp = {{XDF_NEED_MINIMAL}};
 	int ret = 0, i = 0, to_stdout = 0;
 	int level = XDL_MERGE_ZEALOUS_ALNUM;
 	int style = 0, quiet = 0;
@@ -73,7 +73,7 @@ int cmd_merge_file(int argc, const char **argv, const char *prefix)
 	}
 
 	ret = xdl_merge(mmfs + 1, mmfs + 0, names[0], mmfs + 2, names[2],
-			&xpp, XDL_MERGE_FLAGS(level, style, favor), &result);
+			&xmp, XDL_MERGE_FLAGS(level, style, favor), &result);
 
 	for (i = 0; i < 3; i++)
 		free(mmfs[i].ptr);
diff --git a/builtin-pack-objects.c b/builtin-pack-objects.c
index 890f45cf20..59b07fe491 100644
--- a/builtin-pack-objects.c
+++ b/builtin-pack-objects.c
@@ -673,7 +673,7 @@ static void setup_delta_attr_check(struct git_attr_check *check)
 	static struct git_attr *attr_delta;
 
 	if (!attr_delta)
-		attr_delta = git_attr("delta", 5);
+		attr_delta = git_attr("delta");
 
 	check[0].attr = attr_delta;
 }
diff --git a/convert.c b/convert.c
index 950b1f9840..27acce58bc 100644
--- a/convert.c
+++ b/convert.c
@@ -378,9 +378,9 @@ static void setup_convert_check(struct git_attr_check *check)
 	static struct git_attr *attr_filter;
 
 	if (!attr_crlf) {
-		attr_crlf = git_attr("crlf", 4);
-		attr_ident = git_attr("ident", 5);
-		attr_filter = git_attr("filter", 6);
+		attr_crlf = git_attr("crlf");
+		attr_ident = git_attr("ident");
+		attr_filter = git_attr("filter");
 		user_convert_tail = &user_convert;
 		git_config(read_convert_config, NULL);
 	}
diff --git a/ll-merge.c b/ll-merge.c
index 070d66dd40..4c7f11ba84 100644
--- a/ll-merge.c
+++ b/ll-merge.c
@@ -18,7 +18,8 @@ typedef int (*ll_merge_fn)(const struct ll_merge_driver *,
 			   mmfile_t *orig,
 			   mmfile_t *src1, const char *name1,
 			   mmfile_t *src2, const char *name2,
-			   int flag);
+			   int flag,
+			   int marker_size);
 
 struct ll_merge_driver {
 	const char *name;
@@ -38,7 +39,7 @@ static int ll_binary_merge(const struct ll_merge_driver *drv_unused,
 			   mmfile_t *orig,
 			   mmfile_t *src1, const char *name1,
 			   mmfile_t *src2, const char *name2,
-			   int flag)
+			   int flag, int marker_size)
 {
 	/*
 	 * The tentative merge result is "ours" for the final round,
@@ -59,9 +60,9 @@ static int ll_xdl_merge(const struct ll_merge_driver *drv_unused,
 			mmfile_t *orig,
 			mmfile_t *src1, const char *name1,
 			mmfile_t *src2, const char *name2,
-			int flag)
+			int flag, int marker_size)
 {
-	xpparam_t xpp;
+	xmparam_t xmp;
 	int style = 0;
 	int favor = (flag >> 1) & 03;
 
@@ -73,16 +74,19 @@ static int ll_xdl_merge(const struct ll_merge_driver *drv_unused,
 		return ll_binary_merge(drv_unused, result,
 				       path,
 				       orig, src1, name1,
-				       src2, name2, flag);
+				       src2, name2,
+				       flag, marker_size);
 	}
 
-	memset(&xpp, 0, sizeof(xpp));
+	memset(&xmp, 0, sizeof(xmp));
 	if (git_xmerge_style >= 0)
 		style = git_xmerge_style;
+	if (marker_size > 0)
+		xmp.marker_size = marker_size;
 	return xdl_merge(orig,
 			 src1, name1,
 			 src2, name2,
-			 &xpp, XDL_MERGE_FLAGS(XDL_MERGE_ZEALOUS, style, favor),
+			 &xmp, XDL_MERGE_FLAGS(XDL_MERGE_ZEALOUS, style, favor),
 			 result);
 }
 
@@ -92,11 +96,10 @@ static int ll_union_merge(const struct ll_merge_driver *drv_unused,
 			  mmfile_t *orig,
 			  mmfile_t *src1, const char *name1,
 			  mmfile_t *src2, const char *name2,
-			  int flag)
+			  int flag, int marker_size)
 {
 	char *src, *dst;
 	long size;
-	const int marker_size = 7;
 	int status, saved_style;
 
 	/* We have to force the RCS "merge" style */
@@ -104,7 +107,7 @@ static int ll_union_merge(const struct ll_merge_driver *drv_unused,
 	git_xmerge_style = 0;
 	status = ll_xdl_merge(drv_unused, result, path_unused,
 			      orig, src1, NULL, src2, NULL,
-			      flag);
+			      flag, marker_size);
 	git_xmerge_style = saved_style;
 	if (status <= 0)
 		return status;
@@ -165,14 +168,15 @@ static int ll_ext_merge(const struct ll_merge_driver *fn,
 			mmfile_t *orig,
 			mmfile_t *src1, const char *name1,
 			mmfile_t *src2, const char *name2,
-			int flag)
+			int flag, int marker_size)
 {
-	char temp[3][50];
+	char temp[4][50];
 	struct strbuf cmd = STRBUF_INIT;
 	struct strbuf_expand_dict_entry dict[] = {
 		{ "O", temp[0] },
 		{ "A", temp[1] },
 		{ "B", temp[2] },
+		{ "L", temp[3] },
 		{ NULL }
 	};
 	const char *args[] = { NULL, NULL };
@@ -187,6 +191,7 @@ static int ll_ext_merge(const struct ll_merge_driver *fn,
 	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);
 
@@ -279,6 +284,7 @@ static int read_merge_config(const char *var, const char *value, void *cb)
 		 *    %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
@@ -339,16 +345,13 @@ static const struct ll_merge_driver *find_ll_merge_driver(const char *merge_attr
 	return &ll_merge_drv[LL_TEXT_MERGE];
 }
 
-static const char *git_path_check_merge(const char *path)
+static int git_path_check_merge(const char *path, struct git_attr_check check[2])
 {
-	static struct git_attr_check attr_merge_check;
-
-	if (!attr_merge_check.attr)
-		attr_merge_check.attr = git_attr("merge", 5);
-
-	if (git_checkattr(path, 1, &attr_merge_check))
-		return NULL;
-	return attr_merge_check.value;
+	if (!check[0].attr) {
+		check[0].attr = git_attr("merge");
+		check[1].attr = git_attr("conflict-marker-size");
+	}
+	return git_checkattr(path, 2, check);
 }
 
 int ll_merge(mmbuffer_t *result_buf,
@@ -358,17 +361,39 @@ int ll_merge(mmbuffer_t *result_buf,
 	     mmfile_t *theirs, const char *their_label,
 	     int flag)
 {
-	const char *ll_driver_name;
+	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 & 01;
 
-	ll_driver_name = git_path_check_merge(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,
-			  ours, our_label,
-			  theirs, their_label, flag);
+	return driver->fn(driver, result_buf, path, ancestor,
+			  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;
 }
diff --git a/ll-merge.h b/ll-merge.h
index aaed46dec9..57889227b1 100644
--- a/ll-merge.h
+++ b/ll-merge.h
@@ -12,4 +12,6 @@ int ll_merge(mmbuffer_t *result_buf,
 	     mmfile_t *theirs, const char *their_label,
 	     int flag);
 
+int ll_merge_marker_size(const char *path);
+
 #endif
diff --git a/merge-file.c b/merge-file.c
index 3120a95f78..fd34d76e15 100644
--- a/merge-file.c
+++ b/merge-file.c
@@ -1,6 +1,7 @@
 #include "cache.h"
 #include "run-command.h"
 #include "xdiff-interface.h"
+#include "ll-merge.h"
 #include "blob.h"
 
 static int fill_mmfile_blob(mmfile_t *f, struct blob *obj)
@@ -24,16 +25,13 @@ static void free_mmfile(mmfile_t *f)
 	free(f->ptr);
 }
 
-static void *three_way_filemerge(mmfile_t *base, mmfile_t *our, mmfile_t *their, unsigned long *size)
+static void *three_way_filemerge(const char *path, mmfile_t *base, mmfile_t *our, mmfile_t *their, unsigned long *size)
 {
-	mmbuffer_t res;
-	xpparam_t xpp;
 	int merge_status;
+	mmbuffer_t res;
 
-	memset(&xpp, 0, sizeof(xpp));
-	merge_status = xdl_merge(base, our, ".our", their, ".their",
-		&xpp, XDL_MERGE_ZEALOUS, &res);
-
+	merge_status = ll_merge(&res, path, base,
+				our, ".our", their, ".their", 0);
 	if (merge_status < 0)
 		return NULL;
 
@@ -75,7 +73,7 @@ static int generate_common_file(mmfile_t *res, mmfile_t *f1, mmfile_t *f2)
 	return xdi_diff(f1, f2, &xpp, &xecfg, &ecb);
 }
 
-void *merge_file(struct blob *base, struct blob *our, struct blob *their, unsigned long *size)
+void *merge_file(const char *path, struct blob *base, struct blob *our, struct blob *their, unsigned long *size)
 {
 	void *res = NULL;
 	mmfile_t f1, f2, common;
@@ -108,7 +106,7 @@ void *merge_file(struct blob *base, struct blob *our, struct blob *their, unsign
 		if (generate_common_file(&common, &f1, &f2) < 0)
 			goto out_free_f2_f1;
 	}
-	res = three_way_filemerge(&common, &f1, &f2, size);
+	res = three_way_filemerge(path, &common, &f1, &f2, size);
 	free_mmfile(&common);
 out_free_f2_f1:
 	free_mmfile(&f2);
diff --git a/merge-tree.c b/merge-tree.c
index f01e7c81ae..37b94d976c 100644
--- a/merge-tree.c
+++ b/merge-tree.c
@@ -54,7 +54,7 @@ static const char *explanation(struct merge_list *entry)
 	return "removed in remote";
 }
 
-extern void *merge_file(struct blob *, struct blob *, struct blob *, unsigned long *);
+extern void *merge_file(const char *, struct blob *, struct blob *, struct blob *, unsigned long *);
 
 static void *result(struct merge_list *entry, unsigned long *size)
 {
@@ -76,7 +76,7 @@ static void *result(struct merge_list *entry, unsigned long *size)
 	their = NULL;
 	if (entry)
 		their = entry->blob;
-	return merge_file(base, our, their, size);
+	return merge_file(entry->path, base, our, their, size);
 }
 
 static void *origin(struct merge_list *entry, unsigned long *size)
diff --git a/rerere.c b/rerere.c
index 70d0f7afff..a86d73d9dc 100644
--- a/rerere.c
+++ b/rerere.c
@@ -1,11 +1,11 @@
 #include "cache.h"
 #include "string-list.h"
 #include "rerere.h"
-#include "xdiff/xdiff.h"
 #include "xdiff-interface.h"
 #include "dir.h"
 #include "resolve-undo.h"
 #include "ll-merge.h"
+#include "attr.h"
 
 /* if rerere_enabled == -1, fall back to detection of .git/rr-cache */
 static int rerere_enabled = -1;
@@ -99,6 +99,28 @@ static void rerere_io_putstr(const char *str, struct rerere_io *io)
 		ferr_puts(str, io->output, &io->wrerror);
 }
 
+static void rerere_io_putconflict(int ch, int size, struct rerere_io *io)
+{
+	char buf[64];
+
+	while (size) {
+		if (size < sizeof(buf) - 2) {
+			memset(buf, ch, size);
+			buf[size] = '\n';
+			buf[size + 1] = '\0';
+			size = 0;
+		} else {
+			int sz = sizeof(buf) - 1;
+			if (size <= sz)
+				sz -= (sz - size) + 1;
+			memset(buf, ch, sz);
+			buf[sz] = '\0';
+			size -= sz;
+		}
+		rerere_io_putstr(buf, io);
+	}
+}
+
 static void rerere_io_putmem(const char *mem, size_t sz, struct rerere_io *io)
 {
 	if (io->output)
@@ -116,7 +138,17 @@ static int rerere_file_getline(struct strbuf *sb, struct rerere_io *io_)
 	return strbuf_getwholeline(sb, io->input, '\n');
 }
 
-static int handle_path(unsigned char *sha1, struct rerere_io *io)
+static int is_cmarker(char *buf, int marker_char, int marker_size, int want_sp)
+{
+	while (marker_size--)
+		if (*buf++ != marker_char)
+			return 0;
+	if (want_sp && *buf != ' ')
+		return 0;
+	return isspace(*buf);
+}
+
+static int handle_path(unsigned char *sha1, struct rerere_io *io, int marker_size)
 {
 	git_SHA_CTX ctx;
 	int hunk_no = 0;
@@ -130,30 +162,30 @@ static int handle_path(unsigned char *sha1, struct rerere_io *io)
 		git_SHA1_Init(&ctx);
 
 	while (!io->getline(&buf, io)) {
-		if (!prefixcmp(buf.buf, "<<<<<<< ")) {
+		if (is_cmarker(buf.buf, '<', marker_size, 1)) {
 			if (hunk != RR_CONTEXT)
 				goto bad;
 			hunk = RR_SIDE_1;
-		} else if (!prefixcmp(buf.buf, "|||||||") && isspace(buf.buf[7])) {
+		} else if (is_cmarker(buf.buf, '|', marker_size, 0)) {
 			if (hunk != RR_SIDE_1)
 				goto bad;
 			hunk = RR_ORIGINAL;
-		} else if (!prefixcmp(buf.buf, "=======") && isspace(buf.buf[7])) {
+		} else if (is_cmarker(buf.buf, '=', marker_size, 0)) {
 			if (hunk != RR_SIDE_1 && hunk != RR_ORIGINAL)
 				goto bad;
 			hunk = RR_SIDE_2;
-		} else if (!prefixcmp(buf.buf, ">>>>>>> ")) {
+		} else if (is_cmarker(buf.buf, '>', marker_size, 1)) {
 			if (hunk != RR_SIDE_2)
 				goto bad;
 			if (strbuf_cmp(&one, &two) > 0)
 				strbuf_swap(&one, &two);
 			hunk_no++;
 			hunk = RR_CONTEXT;
-			rerere_io_putstr("<<<<<<<\n", io);
+			rerere_io_putconflict('<', marker_size, io);
 			rerere_io_putmem(one.buf, one.len, io);
-			rerere_io_putstr("=======\n", io);
+			rerere_io_putconflict('=', marker_size, io);
 			rerere_io_putmem(two.buf, two.len, io);
-			rerere_io_putstr(">>>>>>>\n", io);
+			rerere_io_putconflict('>', marker_size, io);
 			if (sha1) {
 				git_SHA1_Update(&ctx, one.buf ? one.buf : "",
 					    one.len + 1);
@@ -190,6 +222,7 @@ static int handle_file(const char *path, unsigned char *sha1, const char *output
 {
 	int hunk_no = 0;
 	struct rerere_io_file io;
+	int marker_size = ll_merge_marker_size(path);
 
 	memset(&io, 0, sizeof(io));
 	io.io.getline = rerere_file_getline;
@@ -206,7 +239,7 @@ static int handle_file(const char *path, unsigned char *sha1, const char *output
 		}
 	}
 
-	hunk_no = handle_path(sha1, (struct rerere_io *)&io);
+	hunk_no = handle_path(sha1, (struct rerere_io *)&io, marker_size);
 
 	fclose(io.input);
 	if (io.io.wrerror)
@@ -256,6 +289,7 @@ static int handle_cache(const char *path, unsigned char *sha1, const char *outpu
 	struct cache_entry *ce;
 	int pos, len, i, hunk_no;
 	struct rerere_io_mem io;
+	int marker_size = ll_merge_marker_size(path);
 
 	/*
 	 * Reproduce the conflicted merge in-core
@@ -300,7 +334,7 @@ static int handle_cache(const char *path, unsigned char *sha1, const char *outpu
 	strbuf_init(&io.input, 0);
 	strbuf_attach(&io.input, result.ptr, result.size, result.size);
 
-	hunk_no = handle_path(sha1, (struct rerere_io *)&io);
+	hunk_no = handle_path(sha1, (struct rerere_io *)&io, marker_size);
 	strbuf_release(&io.input);
 	if (io.io.output)
 		fclose(io.io.output);
@@ -332,7 +366,6 @@ static int merge(const char *name, const char *path)
 	int ret;
 	mmfile_t cur, base, other;
 	mmbuffer_t result = {NULL, 0};
-	xpparam_t xpp = {XDF_NEED_MINIMAL};
 
 	if (handle_file(path, NULL, rerere_path(name, "thisimage")) < 0)
 		return 1;
@@ -341,8 +374,7 @@ static int merge(const char *name, const char *path)
 			read_mmfile(&base, rerere_path(name, "preimage")) ||
 			read_mmfile(&other, rerere_path(name, "postimage")))
 		return 1;
-	ret = xdl_merge(&base, &cur, "", &other, "",
-			&xpp, XDL_MERGE_ZEALOUS, &result);
+	ret = ll_merge(&result, path, &base, &cur, "", &other, "", 0);
 	if (!ret) {
 		FILE *f = fopen(path, "w");
 		if (!f)
diff --git a/userdiff.c b/userdiff.c
index 57529ae63d..df992490d5 100644
--- a/userdiff.c
+++ b/userdiff.c
@@ -198,7 +198,7 @@ struct userdiff_driver *userdiff_find_by_path(const char *path)
 	struct git_attr_check check;
 
 	if (!attr)
-		attr = git_attr("diff", 4);
+		attr = git_attr("diff");
 	check.attr = attr;
 
 	if (!path)
diff --git a/ws.c b/ws.c
index 760b5743fa..c0893386e6 100644
--- a/ws.c
+++ b/ws.c
@@ -64,7 +64,7 @@ static void setup_whitespace_attr_check(struct git_attr_check *check)
 	static struct git_attr *attr_whitespace;
 
 	if (!attr_whitespace)
-		attr_whitespace = git_attr("whitespace", 10);
+		attr_whitespace = git_attr("whitespace");
 	check[0].attr = attr_whitespace;
 }
 
diff --git a/xdiff/xdiff.h b/xdiff/xdiff.h
index 8a0efed313..3f6229edbe 100644
--- a/xdiff/xdiff.h
+++ b/xdiff/xdiff.h
@@ -114,9 +114,16 @@ long xdl_mmfile_size(mmfile_t *mmf);
 int xdl_diff(mmfile_t *mf1, mmfile_t *mf2, xpparam_t const *xpp,
 	     xdemitconf_t const *xecfg, xdemitcb_t *ecb);
 
+typedef struct s_xmparam {
+	xpparam_t xpp;
+	int marker_size;
+} xmparam_t;
+
+#define DEFAULT_CONFLICT_MARKER_SIZE 7
+
 int xdl_merge(mmfile_t *orig, mmfile_t *mf1, const char *name1,
 		mmfile_t *mf2, const char *name2,
-		xpparam_t const *xpp, int flags, mmbuffer_t *result);
+		xmparam_t const *xmp, int flags, mmbuffer_t *result);
 
 #ifdef __cplusplus
 }
diff --git a/xdiff/xmerge.c b/xdiff/xmerge.c
index b2ddc75376..8cbe45e675 100644
--- a/xdiff/xmerge.c
+++ b/xdiff/xmerge.c
@@ -145,13 +145,15 @@ static int xdl_orig_copy(xdfenv_t *xe, int i, int count, int add_nl, char *dest)
 static int fill_conflict_hunk(xdfenv_t *xe1, const char *name1,
 			      xdfenv_t *xe2, const char *name2,
 			      int size, int i, int style,
-			      xdmerge_t *m, char *dest)
+			      xdmerge_t *m, char *dest, int marker_size)
 {
-	const int marker_size = 7;
 	int marker1_size = (name1 ? strlen(name1) + 1 : 0);
 	int marker2_size = (name2 ? strlen(name2) + 1 : 0);
 	int j;
 
+	if (marker_size <= 0)
+		marker_size = DEFAULT_CONFLICT_MARKER_SIZE;
+
 	/* Before conflicting part */
 	size += xdl_recs_copy(xe1, i, m->i1 - i, 0,
 			      dest ? dest + size : NULL);
@@ -215,7 +217,8 @@ static int fill_conflict_hunk(xdfenv_t *xe1, const char *name1,
 static int xdl_fill_merge_buffer(xdfenv_t *xe1, const char *name1,
 				 xdfenv_t *xe2, const char *name2,
 				 int favor,
-				 xdmerge_t *m, char *dest, int style)
+				 xdmerge_t *m, char *dest, int style,
+				 int marker_size)
 {
 	int size, i;
 
@@ -225,7 +228,8 @@ static int xdl_fill_merge_buffer(xdfenv_t *xe1, const char *name1,
 
 		if (m->mode == 0)
 			size = fill_conflict_hunk(xe1, name1, xe2, name2,
-						  size, i, style, m, dest);
+						  size, i, style, m, dest,
+						  marker_size);
 		else if (m->mode == 1)
 			size += xdl_recs_copy(xe1, i, m->i1 + m->chg1 - i, 0,
 					      dest ? dest + size : NULL);
@@ -390,8 +394,9 @@ static int xdl_simplify_non_conflicts(xdfenv_t *xe1, xdmerge_t *m,
  */
 static int xdl_do_merge(xdfenv_t *xe1, xdchange_t *xscr1, const char *name1,
 		xdfenv_t *xe2, xdchange_t *xscr2, const char *name2,
-		int flags, xpparam_t const *xpp, mmbuffer_t *result) {
+		int flags, xmparam_t const *xmp, mmbuffer_t *result) {
 	xdmerge_t *changes, *c;
+	xpparam_t const *xpp = &xmp->xpp;
 	int i0, i1, i2, chg0, chg1, chg2;
 	int level = flags & XDL_MERGE_LEVEL_MASK;
 	int style = flags & XDL_MERGE_STYLE_MASK;
@@ -527,8 +532,10 @@ static int xdl_do_merge(xdfenv_t *xe1, xdchange_t *xscr1, const char *name1,
 	}
 	/* output */
 	if (result) {
+		int marker_size = xmp->marker_size;
 		int size = xdl_fill_merge_buffer(xe1, name1, xe2, name2,
-			favor, changes, NULL, style);
+						 favor, changes, NULL, style,
+						 marker_size);
 		result->ptr = xdl_malloc(size);
 		if (!result->ptr) {
 			xdl_cleanup_merge(changes);
@@ -536,17 +543,18 @@ static int xdl_do_merge(xdfenv_t *xe1, xdchange_t *xscr1, const char *name1,
 		}
 		result->size = size;
 		xdl_fill_merge_buffer(xe1, name1, xe2, name2, favor, changes,
-				      result->ptr, style);
+				      result->ptr, style, marker_size);
 	}
 	return xdl_cleanup_merge(changes);
 }
 
 int xdl_merge(mmfile_t *orig, mmfile_t *mf1, const char *name1,
 		mmfile_t *mf2, const char *name2,
-		xpparam_t const *xpp, int flags, mmbuffer_t *result) {
+		xmparam_t const *xmp, int flags, mmbuffer_t *result) {
 	xdchange_t *xscr1, *xscr2;
 	xdfenv_t xe1, xe2;
 	int status;
+	xpparam_t const *xpp = &xmp->xpp;
 
 	result->ptr = NULL;
 	result->size = 0;
@@ -579,7 +587,7 @@ int xdl_merge(mmfile_t *orig, mmfile_t *mf1, const char *name1,
 	} else {
 		status = xdl_do_merge(&xe1, xscr1, name1,
 				      &xe2, xscr2, name2,
-				      flags, xpp, result);
+				      flags, xmp, result);
 	}
 	xdl_free_script(xscr1);
 	xdl_free_script(xscr2);