From: Junio C Hamano <gitster@pobox.com>
Date: Tue, 11 Mar 2008 09:05:12 +0000 (-0700)
Subject: Merge branch 'jc/cherry-pick' (early part)
X-Git-Tag: v1.5.5-rc0~27
X-Git-Url: https://git.tokkee.org/?a=commitdiff_plain;h=5d921e2931e5041884d8f86fdccc9004a7b071cc;p=git.git

Merge branch 'jc/cherry-pick' (early part)

* 'jc/cherry-pick' (early part):
  expose a helper function peel_to_type().
  merge-recursive: split low-level merge functions out.

Conflicts:

	Makefile
	builtin-merge-recursive.c
	sha1_name.c
---

5d921e2931e5041884d8f86fdccc9004a7b071cc
diff --cc Makefile
index 7fbb81578,64f67afb8..514738046
--- a/Makefile
+++ b/Makefile
@@@ -308,8 -301,7 +308,8 @@@ LIB_H = 
  	run-command.h strbuf.h tag.h tree.h git-compat-util.h revision.h \
  	tree-walk.h log-tree.h dir.h path-list.h unpack-trees.h builtin.h \
  	utf8.h reflog-walk.h patch-ids.h attr.h decorate.h progress.h \
- 	mailmap.h remote.h parse-options.h transport.h diffcore.h hash.h fsck.h \
 -	mailmap.h remote.h parse-options.h transport.h diffcore.h hash.h ll-merge.h
++	mailmap.h remote.h parse-options.h transport.h diffcore.h hash.h ll-merge.h fsck.h \
 +	pack-revindex.h
  
  DIFF_OBJS = \
  	diff.o diff-lib.o diffcore-break.o diffcore-order.o \
@@@ -332,8 -324,7 +332,8 @@@ LIB_OBJS = 
  	alloc.o merge-file.o path-list.o help.o unpack-trees.o $(DIFF_OBJS) \
  	color.o wt-status.o archive-zip.o archive-tar.o shallow.o utf8.o \
  	convert.o attr.o decorate.o progress.o mailmap.o symlinks.o remote.o \
 -	transport.o bundle.o walker.o parse-options.o ws.o archive.o ll-merge.o
 +	transport.o bundle.o walker.o parse-options.o ws.o archive.o branch.o \
- 	alias.o fsck.o pack-revindex.o
++	ll-merge.o alias.o fsck.o pack-revindex.o
  
  BUILTIN_OBJS = \
  	builtin-add.o \
diff --cc builtin-merge-recursive.c
index 6fe4102c0,000000000..5a0a7b529
mode 100644,000000..100644
--- a/builtin-merge-recursive.c
+++ b/builtin-merge-recursive.c
@@@ -1,1754 -1,0 +1,1401 @@@
 +/*
 + * Recursive Merge algorithm stolen from git-merge-recursive.py by
 + * Fredrik Kuivinen.
 + * The thieves were Alex Riesen and Johannes Schindelin, in June/July 2006
 + */
 +#include "cache.h"
 +#include "cache-tree.h"
 +#include "commit.h"
 +#include "blob.h"
 +#include "builtin.h"
 +#include "tree-walk.h"
 +#include "diff.h"
 +#include "diffcore.h"
- #include "run-command.h"
 +#include "tag.h"
 +#include "unpack-trees.h"
 +#include "path-list.h"
 +#include "xdiff-interface.h"
++#include "ll-merge.h"
 +#include "interpolate.h"
 +#include "attr.h"
 +#include "merge-recursive.h"
 +
 +static int subtree_merge;
 +
 +static struct tree *shift_tree_object(struct tree *one, struct tree *two)
 +{
 +	unsigned char shifted[20];
 +
 +	/*
 +	 * NEEDSWORK: this limits the recursion depth to hardcoded
 +	 * value '2' to avoid excessive overhead.
 +	 */
 +	shift_tree(one->object.sha1, two->object.sha1, shifted, 2);
 +	if (!hashcmp(two->object.sha1, shifted))
 +		return two;
 +	return lookup_tree(shifted);
 +}
 +
 +/*
 + * A virtual commit has
 + * - (const char *)commit->util set to the name, and
 + * - *(int *)commit->object.sha1 set to the virtual id.
 + */
 +
 +static unsigned commit_list_count(const struct commit_list *l)
 +{
 +	unsigned c = 0;
 +	for (; l; l = l->next )
 +		c++;
 +	return c;
 +}
 +
 +static struct commit *make_virtual_commit(struct tree *tree, const char *comment)
 +{
 +	struct commit *commit = xcalloc(1, sizeof(struct commit));
 +	static unsigned virtual_id = 1;
 +	commit->tree = tree;
 +	commit->util = (void*)comment;
 +	*(int*)commit->object.sha1 = virtual_id++;
 +	/* avoid warnings */
 +	commit->object.parsed = 1;
 +	return commit;
 +}
 +
 +/*
 + * Since we use get_tree_entry(), which does not put the read object into
 + * the object pool, we cannot rely on a == b.
 + */
 +static int sha_eq(const unsigned char *a, const unsigned char *b)
 +{
 +	if (!a && !b)
 +		return 2;
 +	return a && b && hashcmp(a, b) == 0;
 +}
 +
 +/*
 + * Since we want to write the index eventually, we cannot reuse the index
 + * for these (temporary) data.
 + */
 +struct stage_data
 +{
 +	struct
 +	{
 +		unsigned mode;
 +		unsigned char sha[20];
 +	} stages[4];
 +	unsigned processed:1;
 +};
 +
 +static struct path_list current_file_set = {NULL, 0, 0, 1};
 +static struct path_list current_directory_set = {NULL, 0, 0, 1};
 +
 +static int call_depth = 0;
 +static int verbosity = 2;
 +static int rename_limit = -1;
 +static int buffer_output = 1;
 +static struct strbuf obuf = STRBUF_INIT;
 +
 +static int show(int v)
 +{
 +	return (!call_depth && verbosity >= v) || verbosity >= 5;
 +}
 +
 +static void flush_output(void)
 +{
 +	if (obuf.len) {
 +		fputs(obuf.buf, stdout);
 +		strbuf_reset(&obuf);
 +	}
 +}
 +
 +static void output(int v, const char *fmt, ...)
 +{
 +	int len;
 +	va_list ap;
 +
 +	if (!show(v))
 +		return;
 +
 +	strbuf_grow(&obuf, call_depth * 2 + 2);
 +	memset(obuf.buf + obuf.len, ' ', call_depth * 2);
 +	strbuf_setlen(&obuf, obuf.len + call_depth * 2);
 +
 +	va_start(ap, fmt);
 +	len = vsnprintf(obuf.buf + obuf.len, strbuf_avail(&obuf), fmt, ap);
 +	va_end(ap);
 +
 +	if (len < 0)
 +		len = 0;
 +	if (len >= strbuf_avail(&obuf)) {
 +		strbuf_grow(&obuf, len + 2);
 +		va_start(ap, fmt);
 +		len = vsnprintf(obuf.buf + obuf.len, strbuf_avail(&obuf), fmt, ap);
 +		va_end(ap);
 +		if (len >= strbuf_avail(&obuf)) {
 +			die("this should not happen, your snprintf is broken");
 +		}
 +	}
 +	strbuf_setlen(&obuf, obuf.len + len);
 +	strbuf_add(&obuf, "\n", 1);
 +	if (!buffer_output)
 +		flush_output();
 +}
 +
 +static void output_commit_title(struct commit *commit)
 +{
 +	int i;
 +	flush_output();
 +	for (i = call_depth; i--;)
 +		fputs("  ", stdout);
 +	if (commit->util)
 +		printf("virtual %s\n", (char *)commit->util);
 +	else {
 +		printf("%s ", find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV));
 +		if (parse_commit(commit) != 0)
 +			printf("(bad commit)\n");
 +		else {
 +			const char *s;
 +			int len;
 +			for (s = commit->buffer; *s; s++)
 +				if (*s == '\n' && s[1] == '\n') {
 +					s += 2;
 +					break;
 +				}
 +			for (len = 0; s[len] && '\n' != s[len]; len++)
 +				; /* do nothing */
 +			printf("%.*s\n", len, s);
 +		}
 +	}
 +}
 +
 +static int add_cacheinfo(unsigned int mode, const unsigned char *sha1,
 +		const char *path, int stage, int refresh, int options)
 +{
 +	struct cache_entry *ce;
 +	ce = make_cache_entry(mode, sha1 ? sha1 : null_sha1, path, stage, refresh);
 +	if (!ce)
 +		return error("addinfo_cache failed for path '%s'", path);
 +	return add_cache_entry(ce, options);
 +}
 +
 +/*
 + * This is a global variable which is used in a number of places but
 + * only written to in the 'merge' function.
 + *
 + * index_only == 1    => Don't leave any non-stage 0 entries in the cache and
 + *                       don't update the working directory.
 + *               0    => Leave unmerged entries in the cache and update
 + *                       the working directory.
 + */
 +static int index_only = 0;
 +
 +static void init_tree_desc_from_tree(struct tree_desc *desc, struct tree *tree)
 +{
 +	parse_tree(tree);
 +	init_tree_desc(desc, tree->buffer, tree->size);
 +}
 +
 +static int git_merge_trees(int index_only,
 +			   struct tree *common,
 +			   struct tree *head,
 +			   struct tree *merge)
 +{
 +	int rc;
 +	struct tree_desc t[3];
 +	struct unpack_trees_options opts;
 +
 +	memset(&opts, 0, sizeof(opts));
 +	if (index_only)
 +		opts.index_only = 1;
 +	else
 +		opts.update = 1;
 +	opts.merge = 1;
 +	opts.head_idx = 2;
 +	opts.fn = threeway_merge;
 +
 +	init_tree_desc_from_tree(t+0, common);
 +	init_tree_desc_from_tree(t+1, head);
 +	init_tree_desc_from_tree(t+2, merge);
 +
 +	rc = unpack_trees(3, t, &opts);
 +	cache_tree_free(&active_cache_tree);
 +	return rc;
 +}
 +
 +struct tree *write_tree_from_memory(void)
 +{
 +	struct tree *result = NULL;
 +
 +	if (unmerged_cache()) {
 +		int i;
 +		output(0, "There are unmerged index entries:");
 +		for (i = 0; i < active_nr; i++) {
 +			struct cache_entry *ce = active_cache[i];
 +			if (ce_stage(ce))
 +				output(0, "%d %.*s", ce_stage(ce), ce_namelen(ce), ce->name);
 +		}
 +		return NULL;
 +	}
 +
 +	if (!active_cache_tree)
 +		active_cache_tree = cache_tree();
 +
 +	if (!cache_tree_fully_valid(active_cache_tree) &&
 +	    cache_tree_update(active_cache_tree,
 +			      active_cache, active_nr, 0, 0) < 0)
 +		die("error building trees");
 +
 +	result = lookup_tree(active_cache_tree->sha1);
 +
 +	return result;
 +}
 +
 +static int save_files_dirs(const unsigned char *sha1,
 +		const char *base, int baselen, const char *path,
 +		unsigned int mode, int stage)
 +{
 +	int len = strlen(path);
 +	char *newpath = xmalloc(baselen + len + 1);
 +	memcpy(newpath, base, baselen);
 +	memcpy(newpath + baselen, path, len);
 +	newpath[baselen + len] = '\0';
 +
 +	if (S_ISDIR(mode))
 +		path_list_insert(newpath, &current_directory_set);
 +	else
 +		path_list_insert(newpath, &current_file_set);
 +	free(newpath);
 +
 +	return READ_TREE_RECURSIVE;
 +}
 +
 +static int get_files_dirs(struct tree *tree)
 +{
 +	int n;
 +	if (read_tree_recursive(tree, "", 0, 0, NULL, save_files_dirs) != 0)
 +		return 0;
 +	n = current_file_set.nr + current_directory_set.nr;
 +	return n;
 +}
 +
 +/*
 + * Returns an index_entry instance which doesn't have to correspond to
 + * a real cache entry in Git's index.
 + */
 +static struct stage_data *insert_stage_data(const char *path,
 +		struct tree *o, struct tree *a, struct tree *b,
 +		struct path_list *entries)
 +{
 +	struct path_list_item *item;
 +	struct stage_data *e = xcalloc(1, sizeof(struct stage_data));
 +	get_tree_entry(o->object.sha1, path,
 +			e->stages[1].sha, &e->stages[1].mode);
 +	get_tree_entry(a->object.sha1, path,
 +			e->stages[2].sha, &e->stages[2].mode);
 +	get_tree_entry(b->object.sha1, path,
 +			e->stages[3].sha, &e->stages[3].mode);
 +	item = path_list_insert(path, entries);
 +	item->util = e;
 +	return e;
 +}
 +
 +/*
 + * Create a dictionary mapping file names to stage_data objects. The
 + * dictionary contains one entry for every path with a non-zero stage entry.
 + */
 +static struct path_list *get_unmerged(void)
 +{
 +	struct path_list *unmerged = xcalloc(1, sizeof(struct path_list));
 +	int i;
 +
 +	unmerged->strdup_paths = 1;
 +
 +	for (i = 0; i < active_nr; i++) {
 +		struct path_list_item *item;
 +		struct stage_data *e;
 +		struct cache_entry *ce = active_cache[i];
 +		if (!ce_stage(ce))
 +			continue;
 +
 +		item = path_list_lookup(ce->name, unmerged);
 +		if (!item) {
 +			item = path_list_insert(ce->name, unmerged);
 +			item->util = xcalloc(1, sizeof(struct stage_data));
 +		}
 +		e = item->util;
 +		e->stages[ce_stage(ce)].mode = ce->ce_mode;
 +		hashcpy(e->stages[ce_stage(ce)].sha, ce->sha1);
 +	}
 +
 +	return unmerged;
 +}
 +
 +struct rename
 +{
 +	struct diff_filepair *pair;
 +	struct stage_data *src_entry;
 +	struct stage_data *dst_entry;
 +	unsigned processed:1;
 +};
 +
 +/*
 + * Get information of all renames which occurred between 'o_tree' and
 + * 'tree'. We need the three trees in the merge ('o_tree', 'a_tree' and
 + * 'b_tree') to be able to associate the correct cache entries with
 + * the rename information. 'tree' is always equal to either a_tree or b_tree.
 + */
 +static struct path_list *get_renames(struct tree *tree,
 +					struct tree *o_tree,
 +					struct tree *a_tree,
 +					struct tree *b_tree,
 +					struct path_list *entries)
 +{
 +	int i;
 +	struct path_list *renames;
 +	struct diff_options opts;
 +
 +	renames = xcalloc(1, sizeof(struct path_list));
 +	diff_setup(&opts);
 +	DIFF_OPT_SET(&opts, RECURSIVE);
 +	opts.detect_rename = DIFF_DETECT_RENAME;
 +	opts.rename_limit = rename_limit;
 +	opts.output_format = DIFF_FORMAT_NO_OUTPUT;
 +	if (diff_setup_done(&opts) < 0)
 +		die("diff setup failed");
 +	diff_tree_sha1(o_tree->object.sha1, tree->object.sha1, "", &opts);
 +	diffcore_std(&opts);
 +	for (i = 0; i < diff_queued_diff.nr; ++i) {
 +		struct path_list_item *item;
 +		struct rename *re;
 +		struct diff_filepair *pair = diff_queued_diff.queue[i];
 +		if (pair->status != 'R') {
 +			diff_free_filepair(pair);
 +			continue;
 +		}
 +		re = xmalloc(sizeof(*re));
 +		re->processed = 0;
 +		re->pair = pair;
 +		item = path_list_lookup(re->pair->one->path, entries);
 +		if (!item)
 +			re->src_entry = insert_stage_data(re->pair->one->path,
 +					o_tree, a_tree, b_tree, entries);
 +		else
 +			re->src_entry = item->util;
 +
 +		item = path_list_lookup(re->pair->two->path, entries);
 +		if (!item)
 +			re->dst_entry = insert_stage_data(re->pair->two->path,
 +					o_tree, a_tree, b_tree, entries);
 +		else
 +			re->dst_entry = item->util;
 +		item = path_list_insert(pair->one->path, renames);
 +		item->util = re;
 +	}
 +	opts.output_format = DIFF_FORMAT_NO_OUTPUT;
 +	diff_queued_diff.nr = 0;
 +	diff_flush(&opts);
 +	return renames;
 +}
 +
 +static int update_stages(const char *path, struct diff_filespec *o,
 +			 struct diff_filespec *a, struct diff_filespec *b,
 +			 int clear)
 +{
 +	int options = ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE;
 +	if (clear)
 +		if (remove_file_from_cache(path))
 +			return -1;
 +	if (o)
 +		if (add_cacheinfo(o->mode, o->sha1, path, 1, 0, options))
 +			return -1;
 +	if (a)
 +		if (add_cacheinfo(a->mode, a->sha1, path, 2, 0, options))
 +			return -1;
 +	if (b)
 +		if (add_cacheinfo(b->mode, b->sha1, path, 3, 0, options))
 +			return -1;
 +	return 0;
 +}
 +
 +static int remove_path(const char *name)
 +{
 +	int ret;
 +	char *slash, *dirs;
 +
 +	ret = unlink(name);
 +	if (ret)
 +		return ret;
 +	dirs = xstrdup(name);
 +	while ((slash = strrchr(name, '/'))) {
 +		*slash = '\0';
 +		if (rmdir(name) != 0)
 +			break;
 +	}
 +	free(dirs);
 +	return ret;
 +}
 +
 +static int remove_file(int clean, const char *path, int no_wd)
 +{
 +	int update_cache = index_only || clean;
 +	int update_working_directory = !index_only && !no_wd;
 +
 +	if (update_cache) {
 +		if (remove_file_from_cache(path))
 +			return -1;
 +	}
 +	if (update_working_directory) {
 +		unlink(path);
 +		if (errno != ENOENT || errno != EISDIR)
 +			return -1;
 +		remove_path(path);
 +	}
 +	return 0;
 +}
 +
 +static char *unique_path(const char *path, const char *branch)
 +{
 +	char *newpath = xmalloc(strlen(path) + 1 + strlen(branch) + 8 + 1);
 +	int suffix = 0;
 +	struct stat st;
 +	char *p = newpath + strlen(path);
 +	strcpy(newpath, path);
 +	*(p++) = '~';
 +	strcpy(p, branch);
 +	for (; *p; ++p)
 +		if ('/' == *p)
 +			*p = '_';
 +	while (path_list_has_path(&current_file_set, newpath) ||
 +	       path_list_has_path(&current_directory_set, newpath) ||
 +	       lstat(newpath, &st) == 0)
 +		sprintf(p, "_%d", suffix++);
 +
 +	path_list_insert(newpath, &current_file_set);
 +	return newpath;
 +}
 +
 +static int mkdir_p(const char *path, unsigned long mode)
 +{
 +	/* path points to cache entries, so xstrdup before messing with it */
 +	char *buf = xstrdup(path);
 +	int result = safe_create_leading_directories(buf);
 +	free(buf);
 +	return result;
 +}
 +
 +static void flush_buffer(int fd, const char *buf, unsigned long size)
 +{
 +	while (size > 0) {
 +		long ret = write_in_full(fd, buf, size);
 +		if (ret < 0) {
 +			/* Ignore epipe */
 +			if (errno == EPIPE)
 +				break;
 +			die("merge-recursive: %s", strerror(errno));
 +		} else if (!ret) {
 +			die("merge-recursive: disk full?");
 +		}
 +		size -= ret;
 +		buf += ret;
 +	}
 +}
 +
 +static int make_room_for_path(const char *path)
 +{
 +	int status;
 +	const char *msg = "failed to create path '%s'%s";
 +
 +	status = mkdir_p(path, 0777);
 +	if (status) {
 +		if (status == -3) {
 +			/* something else exists */
 +			error(msg, path, ": perhaps a D/F conflict?");
 +			return -1;
 +		}
 +		die(msg, path, "");
 +	}
 +
 +	/* Successful unlink is good.. */
 +	if (!unlink(path))
 +		return 0;
 +	/* .. and so is no existing file */
 +	if (errno == ENOENT)
 +		return 0;
 +	/* .. but not some other error (who really cares what?) */
 +	return error(msg, path, ": perhaps a D/F conflict?");
 +}
 +
 +static void update_file_flags(const unsigned char *sha,
 +			      unsigned mode,
 +			      const char *path,
 +			      int update_cache,
 +			      int update_wd)
 +{
 +	if (index_only)
 +		update_wd = 0;
 +
 +	if (update_wd) {
 +		enum object_type type;
 +		void *buf;
 +		unsigned long size;
 +
 +		if (S_ISGITLINK(mode))
 +			die("cannot read object %s '%s': It is a submodule!",
 +			    sha1_to_hex(sha), path);
 +
 +		buf = read_sha1_file(sha, &type, &size);
 +		if (!buf)
 +			die("cannot read object %s '%s'", sha1_to_hex(sha), path);
 +		if (type != OBJ_BLOB)
 +			die("blob expected for %s '%s'", sha1_to_hex(sha), path);
 +
 +		if (make_room_for_path(path) < 0) {
 +			update_wd = 0;
 +			goto update_index;
 +		}
 +		if (S_ISREG(mode) || (!has_symlinks && S_ISLNK(mode))) {
 +			int fd;
 +			if (mode & 0100)
 +				mode = 0777;
 +			else
 +				mode = 0666;
 +			fd = open(path, O_WRONLY | O_TRUNC | O_CREAT, mode);
 +			if (fd < 0)
 +				die("failed to open %s: %s", path, strerror(errno));
 +			flush_buffer(fd, buf, size);
 +			close(fd);
 +		} else if (S_ISLNK(mode)) {
 +			char *lnk = xmemdupz(buf, size);
 +			mkdir_p(path, 0777);
 +			unlink(path);
 +			symlink(lnk, path);
 +			free(lnk);
 +		} else
 +			die("do not know what to do with %06o %s '%s'",
 +			    mode, sha1_to_hex(sha), path);
 +	}
 + update_index:
 +	if (update_cache)
 +		add_cacheinfo(mode, sha, path, 0, update_wd, ADD_CACHE_OK_TO_ADD);
 +}
 +
 +static void update_file(int clean,
 +			const unsigned char *sha,
 +			unsigned mode,
 +			const char *path)
 +{
 +	update_file_flags(sha, mode, path, index_only || clean, !index_only);
 +}
 +
 +/* Low level file merging, update and removal */
 +
 +struct merge_file_info
 +{
 +	unsigned char sha[20];
 +	unsigned mode;
 +	unsigned clean:1,
 +		 merge:1;
 +};
 +
 +static void fill_mm(const unsigned char *sha1, mmfile_t *mm)
 +{
 +	unsigned long size;
 +	enum object_type type;
 +
 +	if (!hashcmp(sha1, null_sha1)) {
 +		mm->ptr = xstrdup("");
 +		mm->size = 0;
 +		return;
 +	}
 +
 +	mm->ptr = read_sha1_file(sha1, &type, &size);
 +	if (!mm->ptr || type != OBJ_BLOB)
 +		die("unable to read blob object %s", sha1_to_hex(sha1));
 +	mm->size = size;
 +}
 +
- /*
-  * Customizable low-level merge drivers support.
-  */
- 
- struct ll_merge_driver;
- typedef int (*ll_merge_fn)(const struct ll_merge_driver *,
- 			   const char *path,
- 			   mmfile_t *orig,
- 			   mmfile_t *src1, const char *name1,
- 			   mmfile_t *src2, const char *name2,
- 			   mmbuffer_t *result);
- 
- 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,
- 			   const char *path_unused,
- 			   mmfile_t *orig,
- 			   mmfile_t *src1, const char *name1,
- 			   mmfile_t *src2, const char *name2,
- 			   mmbuffer_t *result)
- {
- 	/*
- 	 * 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 = index_only ? 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,
- 			const char *path_unused,
- 			mmfile_t *orig,
- 			mmfile_t *src1, const char *name1,
- 			mmfile_t *src2, const char *name2,
- 			mmbuffer_t *result)
- {
- 	xpparam_t xpp;
- 
- 	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 vs. %s\n",
- 			name1, name2);
- 		return ll_binary_merge(drv_unused, path_unused,
- 				       orig, src1, name1,
- 				       src2, name2,
- 				       result);
- 	}
- 
- 	memset(&xpp, 0, sizeof(xpp));
- 	return xdl_merge(orig,
- 			 src1, name1,
- 			 src2, name2,
- 			 &xpp, XDL_MERGE_ZEALOUS,
- 			 result);
- }
- 
- static int ll_union_merge(const struct ll_merge_driver *drv_unused,
- 			  const char *path_unused,
- 			  mmfile_t *orig,
- 			  mmfile_t *src1, const char *name1,
- 			  mmfile_t *src2, const char *name2,
- 			  mmbuffer_t *result)
- {
- 	char *src, *dst;
- 	long size;
- 	const int marker_size = 7;
- 
- 	int status = ll_xdl_merge(drv_unused, path_unused,
- 				  orig, src1, NULL, src2, NULL, result);
- 	if (status <= 0)
- 		return status;
- 	size = result->size;
- 	src = dst = result->ptr;
- 	while (size) {
- 		char ch;
- 		if ((marker_size < size) &&
- 		    (*src == '<' || *src == '=' || *src == '>')) {
- 			int i;
- 			ch = *src;
- 			for (i = 0; i < marker_size; i++)
- 				if (src[i] != ch)
- 					goto not_a_marker;
- 			if (src[marker_size] != '\n')
- 				goto not_a_marker;
- 			src += marker_size + 1;
- 			size -= marker_size + 1;
- 			continue;
- 		}
- 	not_a_marker:
- 		do {
- 			ch = *src++;
- 			*dst++ = ch;
- 			size--;
- 		} while (ch != '\n' && size);
- 	}
- 	result->size = dst - result->ptr;
- 	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("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,
- 			const char *path,
- 			mmfile_t *orig,
- 			mmfile_t *src1, const char *name1,
- 			mmfile_t *src2, const char *name2,
- 			mmbuffer_t *result)
- {
- 	char temp[3][50];
- 	char cmdbuf[2048];
- 	struct interp table[] = {
- 		{ "%O" },
- 		{ "%A" },
- 		{ "%B" },
- 	};
- 	struct child_process child;
- 	const char *args[20];
- 	int status, fd, i;
- 	struct stat st;
- 
- 	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]);
- 
- 	interp_set_entry(table, 0, temp[0]);
- 	interp_set_entry(table, 1, temp[1]);
- 	interp_set_entry(table, 2, temp[2]);
- 
- 	output(1, "merging %s using %s", path,
- 	       fn->description ? fn->description : fn->name);
- 
- 	interpolate(cmdbuf, sizeof(cmdbuf), fn->cmdline, table, 3);
- 
- 	memset(&child, 0, sizeof(child));
- 	child.argv = args;
- 	args[0] = "sh";
- 	args[1] = "-c";
- 	args[2] = cmdbuf;
- 	args[3] = NULL;
- 
- 	status = run_command(&child);
- 	if (status < -ERR_RUN_COMMAND_FORK)
- 		; /* failure in run-command */
- 	else
- 		status = -status;
- 	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(temp[i]);
- 	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)
- {
- 	struct ll_merge_driver *fn;
- 	const char *ep, *name;
- 	int namelen;
- 
- 	if (!strcmp(var, "merge.default")) {
- 		if (!value)
- 			return config_error_nonbool(var);
- 		default_ll_merge = strdup(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 config_error_nonbool(var);
- 		fn->description = strdup(value);
- 		return 0;
- 	}
- 
- 	if (!strcmp("driver", ep)) {
- 		if (!value)
- 			return config_error_nonbool(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.
- 		 *
- 		 * 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 = strdup(value);
- 		return 0;
- 	}
- 
- 	if (!strcmp("recursive", ep)) {
- 		if (!value)
- 			return config_error_nonbool(var);
- 		fn->recursive = strdup(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);
- }
- 
- 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 const char *git_path_check_merge(const char *path)
- {
- 	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;
- }
- 
- static int ll_merge(mmbuffer_t *result_buf,
- 		    struct diff_filespec *o,
- 		    struct diff_filespec *a,
- 		    struct diff_filespec *b,
- 		    const char *branch1,
- 		    const char *branch2)
++static int merge_3way(mmbuffer_t *result_buf,
++		      struct diff_filespec *o,
++		      struct diff_filespec *a,
++		      struct diff_filespec *b,
++		      const char *branch1,
++		      const char *branch2)
 +{
 +	mmfile_t orig, src1, src2;
 +	char *name1, *name2;
 +	int merge_status;
- 	const char *ll_driver_name;
- 	const struct ll_merge_driver *driver;
 +
 +	name1 = xstrdup(mkpath("%s:%s", branch1, a->path));
 +	name2 = xstrdup(mkpath("%s:%s", branch2, b->path));
 +
 +	fill_mm(o->sha1, &orig);
 +	fill_mm(a->sha1, &src1);
 +	fill_mm(b->sha1, &src2);
 +
- 	ll_driver_name = git_path_check_merge(a->path);
- 	driver = find_ll_merge_driver(ll_driver_name);
- 
- 	if (index_only && driver->recursive)
- 		driver = find_ll_merge_driver(driver->recursive);
- 	merge_status = driver->fn(driver, a->path,
- 				  &orig, &src1, name1, &src2, name2,
- 				  result_buf);
++	merge_status = ll_merge(result_buf, a->path, &orig,
++				&src1, name1, &src2, name2,
++				index_only);
 +
 +	free(name1);
 +	free(name2);
 +	free(orig.ptr);
 +	free(src1.ptr);
 +	free(src2.ptr);
 +	return merge_status;
 +}
 +
 +static struct merge_file_info merge_file(struct diff_filespec *o,
 +		struct diff_filespec *a, struct diff_filespec *b,
 +		const char *branch1, const char *branch2)
 +{
 +	struct merge_file_info result;
 +	result.merge = 0;
 +	result.clean = 1;
 +
 +	if ((S_IFMT & a->mode) != (S_IFMT & b->mode)) {
 +		result.clean = 0;
 +		if (S_ISREG(a->mode)) {
 +			result.mode = a->mode;
 +			hashcpy(result.sha, a->sha1);
 +		} else {
 +			result.mode = b->mode;
 +			hashcpy(result.sha, b->sha1);
 +		}
 +	} else {
 +		if (!sha_eq(a->sha1, o->sha1) && !sha_eq(b->sha1, o->sha1))
 +			result.merge = 1;
 +
 +		result.mode = a->mode == o->mode ? b->mode: a->mode;
 +
 +		if (sha_eq(a->sha1, o->sha1))
 +			hashcpy(result.sha, b->sha1);
 +		else if (sha_eq(b->sha1, o->sha1))
 +			hashcpy(result.sha, a->sha1);
 +		else if (S_ISREG(a->mode)) {
 +			mmbuffer_t result_buf;
 +			int merge_status;
 +
- 			merge_status = ll_merge(&result_buf, o, a, b,
- 						branch1, branch2);
++			merge_status = merge_3way(&result_buf, o, a, b,
++						  branch1, branch2);
 +
 +			if ((merge_status < 0) || !result_buf.ptr)
 +				die("Failed to execute internal merge");
 +
 +			if (write_sha1_file(result_buf.ptr, result_buf.size,
 +					    blob_type, result.sha))
 +				die("Unable to add %s to database",
 +				    a->path);
 +
 +			free(result_buf.ptr);
 +			result.clean = (merge_status == 0);
 +		} else if (S_ISGITLINK(a->mode)) {
 +			result.clean = 0;
 +			hashcpy(result.sha, a->sha1);
 +		} else if (S_ISLNK(a->mode)) {
 +			hashcpy(result.sha, a->sha1);
 +
 +			if (!sha_eq(a->sha1, b->sha1))
 +				result.clean = 0;
 +		} else {
 +			die("unsupported object type in the tree");
 +		}
 +	}
 +
 +	return result;
 +}
 +
 +static void conflict_rename_rename(struct rename *ren1,
 +				   const char *branch1,
 +				   struct rename *ren2,
 +				   const char *branch2)
 +{
 +	char *del[2];
 +	int delp = 0;
 +	const char *ren1_dst = ren1->pair->two->path;
 +	const char *ren2_dst = ren2->pair->two->path;
 +	const char *dst_name1 = ren1_dst;
 +	const char *dst_name2 = ren2_dst;
 +	if (path_list_has_path(&current_directory_set, ren1_dst)) {
 +		dst_name1 = del[delp++] = unique_path(ren1_dst, branch1);
 +		output(1, "%s is a directory in %s added as %s instead",
 +		       ren1_dst, branch2, dst_name1);
 +		remove_file(0, ren1_dst, 0);
 +	}
 +	if (path_list_has_path(&current_directory_set, ren2_dst)) {
 +		dst_name2 = del[delp++] = unique_path(ren2_dst, branch2);
 +		output(1, "%s is a directory in %s added as %s instead",
 +		       ren2_dst, branch1, dst_name2);
 +		remove_file(0, ren2_dst, 0);
 +	}
 +	if (index_only) {
 +		remove_file_from_cache(dst_name1);
 +		remove_file_from_cache(dst_name2);
 +		/*
 +		 * Uncomment to leave the conflicting names in the resulting tree
 +		 *
 +		 * update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, dst_name1);
 +		 * update_file(0, ren2->pair->two->sha1, ren2->pair->two->mode, dst_name2);
 +		 */
 +	} else {
 +		update_stages(dst_name1, NULL, ren1->pair->two, NULL, 1);
 +		update_stages(dst_name2, NULL, NULL, ren2->pair->two, 1);
 +	}
 +	while (delp--)
 +		free(del[delp]);
 +}
 +
 +static void conflict_rename_dir(struct rename *ren1,
 +				const char *branch1)
 +{
 +	char *new_path = unique_path(ren1->pair->two->path, branch1);
 +	output(1, "Renamed %s to %s instead", ren1->pair->one->path, new_path);
 +	remove_file(0, ren1->pair->two->path, 0);
 +	update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path);
 +	free(new_path);
 +}
 +
 +static void conflict_rename_rename_2(struct rename *ren1,
 +				     const char *branch1,
 +				     struct rename *ren2,
 +				     const char *branch2)
 +{
 +	char *new_path1 = unique_path(ren1->pair->two->path, branch1);
 +	char *new_path2 = unique_path(ren2->pair->two->path, branch2);
 +	output(1, "Renamed %s to %s and %s to %s instead",
 +	       ren1->pair->one->path, new_path1,
 +	       ren2->pair->one->path, new_path2);
 +	remove_file(0, ren1->pair->two->path, 0);
 +	update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path1);
 +	update_file(0, ren2->pair->two->sha1, ren2->pair->two->mode, new_path2);
 +	free(new_path2);
 +	free(new_path1);
 +}
 +
 +static int process_renames(struct path_list *a_renames,
 +			   struct path_list *b_renames,
 +			   const char *a_branch,
 +			   const char *b_branch)
 +{
 +	int clean_merge = 1, i, j;
 +	struct path_list a_by_dst = {NULL, 0, 0, 0}, b_by_dst = {NULL, 0, 0, 0};
 +	const struct rename *sre;
 +
 +	for (i = 0; i < a_renames->nr; i++) {
 +		sre = a_renames->items[i].util;
 +		path_list_insert(sre->pair->two->path, &a_by_dst)->util
 +			= sre->dst_entry;
 +	}
 +	for (i = 0; i < b_renames->nr; i++) {
 +		sre = b_renames->items[i].util;
 +		path_list_insert(sre->pair->two->path, &b_by_dst)->util
 +			= sre->dst_entry;
 +	}
 +
 +	for (i = 0, j = 0; i < a_renames->nr || j < b_renames->nr;) {
 +		int compare;
 +		char *src;
 +		struct path_list *renames1, *renames2, *renames2Dst;
 +		struct rename *ren1 = NULL, *ren2 = NULL;
 +		const char *branch1, *branch2;
 +		const char *ren1_src, *ren1_dst;
 +
 +		if (i >= a_renames->nr) {
 +			compare = 1;
 +			ren2 = b_renames->items[j++].util;
 +		} else if (j >= b_renames->nr) {
 +			compare = -1;
 +			ren1 = a_renames->items[i++].util;
 +		} else {
 +			compare = strcmp(a_renames->items[i].path,
 +					b_renames->items[j].path);
 +			if (compare <= 0)
 +				ren1 = a_renames->items[i++].util;
 +			if (compare >= 0)
 +				ren2 = b_renames->items[j++].util;
 +		}
 +
 +		/* TODO: refactor, so that 1/2 are not needed */
 +		if (ren1) {
 +			renames1 = a_renames;
 +			renames2 = b_renames;
 +			renames2Dst = &b_by_dst;
 +			branch1 = a_branch;
 +			branch2 = b_branch;
 +		} else {
 +			struct rename *tmp;
 +			renames1 = b_renames;
 +			renames2 = a_renames;
 +			renames2Dst = &a_by_dst;
 +			branch1 = b_branch;
 +			branch2 = a_branch;
 +			tmp = ren2;
 +			ren2 = ren1;
 +			ren1 = tmp;
 +		}
 +		src = ren1->pair->one->path;
 +
 +		ren1->dst_entry->processed = 1;
 +		ren1->src_entry->processed = 1;
 +
 +		if (ren1->processed)
 +			continue;
 +		ren1->processed = 1;
 +
 +		ren1_src = ren1->pair->one->path;
 +		ren1_dst = ren1->pair->two->path;
 +
 +		if (ren2) {
 +			const char *ren2_src = ren2->pair->one->path;
 +			const char *ren2_dst = ren2->pair->two->path;
 +			/* Renamed in 1 and renamed in 2 */
 +			if (strcmp(ren1_src, ren2_src) != 0)
 +				die("ren1.src != ren2.src");
 +			ren2->dst_entry->processed = 1;
 +			ren2->processed = 1;
 +			if (strcmp(ren1_dst, ren2_dst) != 0) {
 +				clean_merge = 0;
 +				output(1, "CONFLICT (rename/rename): "
 +				       "Rename \"%s\"->\"%s\" in branch \"%s\" "
 +				       "rename \"%s\"->\"%s\" in \"%s\"%s",
 +				       src, ren1_dst, branch1,
 +				       src, ren2_dst, branch2,
 +				       index_only ? " (left unresolved)": "");
 +				if (index_only) {
 +					remove_file_from_cache(src);
 +					update_file(0, ren1->pair->one->sha1,
 +						    ren1->pair->one->mode, src);
 +				}
 +				conflict_rename_rename(ren1, branch1, ren2, branch2);
 +			} else {
 +				struct merge_file_info mfi;
 +				remove_file(1, ren1_src, 1);
 +				mfi = merge_file(ren1->pair->one,
 +						 ren1->pair->two,
 +						 ren2->pair->two,
 +						 branch1,
 +						 branch2);
 +				if (mfi.merge || !mfi.clean)
 +					output(1, "Renamed %s->%s", src, ren1_dst);
 +
 +				if (mfi.merge)
 +					output(2, "Auto-merged %s", ren1_dst);
 +
 +				if (!mfi.clean) {
 +					output(1, "CONFLICT (content): merge conflict in %s",
 +					       ren1_dst);
 +					clean_merge = 0;
 +
 +					if (!index_only)
 +						update_stages(ren1_dst,
 +							      ren1->pair->one,
 +							      ren1->pair->two,
 +							      ren2->pair->two,
 +							      1 /* clear */);
 +				}
 +				update_file(mfi.clean, mfi.sha, mfi.mode, ren1_dst);
 +			}
 +		} else {
 +			/* Renamed in 1, maybe changed in 2 */
 +			struct path_list_item *item;
 +			/* we only use sha1 and mode of these */
 +			struct diff_filespec src_other, dst_other;
 +			int try_merge, stage = a_renames == renames1 ? 3: 2;
 +
 +			remove_file(1, ren1_src, index_only || stage == 3);
 +
 +			hashcpy(src_other.sha1, ren1->src_entry->stages[stage].sha);
 +			src_other.mode = ren1->src_entry->stages[stage].mode;
 +			hashcpy(dst_other.sha1, ren1->dst_entry->stages[stage].sha);
 +			dst_other.mode = ren1->dst_entry->stages[stage].mode;
 +
 +			try_merge = 0;
 +
 +			if (path_list_has_path(&current_directory_set, ren1_dst)) {
 +				clean_merge = 0;
 +				output(1, "CONFLICT (rename/directory): Renamed %s->%s in %s "
 +				       " directory %s added in %s",
 +				       ren1_src, ren1_dst, branch1,
 +				       ren1_dst, branch2);
 +				conflict_rename_dir(ren1, branch1);
 +			} else if (sha_eq(src_other.sha1, null_sha1)) {
 +				clean_merge = 0;
 +				output(1, "CONFLICT (rename/delete): Renamed %s->%s in %s "
 +				       "and deleted in %s",
 +				       ren1_src, ren1_dst, branch1,
 +				       branch2);
 +				update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, ren1_dst);
 +			} else if (!sha_eq(dst_other.sha1, null_sha1)) {
 +				const char *new_path;
 +				clean_merge = 0;
 +				try_merge = 1;
 +				output(1, "CONFLICT (rename/add): Renamed %s->%s in %s. "
 +				       "%s added in %s",
 +				       ren1_src, ren1_dst, branch1,
 +				       ren1_dst, branch2);
 +				new_path = unique_path(ren1_dst, branch2);
 +				output(1, "Added as %s instead", new_path);
 +				update_file(0, dst_other.sha1, dst_other.mode, new_path);
 +			} else if ((item = path_list_lookup(ren1_dst, renames2Dst))) {
 +				ren2 = item->util;
 +				clean_merge = 0;
 +				ren2->processed = 1;
 +				output(1, "CONFLICT (rename/rename): Renamed %s->%s in %s. "
 +				       "Renamed %s->%s in %s",
 +				       ren1_src, ren1_dst, branch1,
 +				       ren2->pair->one->path, ren2->pair->two->path, branch2);
 +				conflict_rename_rename_2(ren1, branch1, ren2, branch2);
 +			} else
 +				try_merge = 1;
 +
 +			if (try_merge) {
 +				struct diff_filespec *o, *a, *b;
 +				struct merge_file_info mfi;
 +				src_other.path = (char *)ren1_src;
 +
 +				o = ren1->pair->one;
 +				if (a_renames == renames1) {
 +					a = ren1->pair->two;
 +					b = &src_other;
 +				} else {
 +					b = ren1->pair->two;
 +					a = &src_other;
 +				}
 +				mfi = merge_file(o, a, b,
 +						a_branch, b_branch);
 +
 +				if (mfi.clean &&
 +				    sha_eq(mfi.sha, ren1->pair->two->sha1) &&
 +				    mfi.mode == ren1->pair->two->mode)
 +					/*
 +					 * This messaged is part of
 +					 * t6022 test. If you change
 +					 * it update the test too.
 +					 */
 +					output(3, "Skipped %s (merged same as existing)", ren1_dst);
 +				else {
 +					if (mfi.merge || !mfi.clean)
 +						output(1, "Renamed %s => %s", ren1_src, ren1_dst);
 +					if (mfi.merge)
 +						output(2, "Auto-merged %s", ren1_dst);
 +					if (!mfi.clean) {
 +						output(1, "CONFLICT (rename/modify): Merge conflict in %s",
 +						       ren1_dst);
 +						clean_merge = 0;
 +
 +						if (!index_only)
 +							update_stages(ren1_dst,
 +								      o, a, b, 1);
 +					}
 +					update_file(mfi.clean, mfi.sha, mfi.mode, ren1_dst);
 +				}
 +			}
 +		}
 +	}
 +	path_list_clear(&a_by_dst, 0);
 +	path_list_clear(&b_by_dst, 0);
 +
 +	return clean_merge;
 +}
 +
 +static unsigned char *stage_sha(const unsigned char *sha, unsigned mode)
 +{
 +	return (is_null_sha1(sha) || mode == 0) ? NULL: (unsigned char *)sha;
 +}
 +
 +/* Per entry merge function */
 +static int process_entry(const char *path, struct stage_data *entry,
 +			 const char *branch1,
 +			 const char *branch2)
 +{
 +	/*
 +	printf("processing entry, clean cache: %s\n", index_only ? "yes": "no");
 +	print_index_entry("\tpath: ", entry);
 +	*/
 +	int clean_merge = 1;
 +	unsigned o_mode = entry->stages[1].mode;
 +	unsigned a_mode = entry->stages[2].mode;
 +	unsigned b_mode = entry->stages[3].mode;
 +	unsigned char *o_sha = stage_sha(entry->stages[1].sha, o_mode);
 +	unsigned char *a_sha = stage_sha(entry->stages[2].sha, a_mode);
 +	unsigned char *b_sha = stage_sha(entry->stages[3].sha, b_mode);
 +
 +	if (o_sha && (!a_sha || !b_sha)) {
 +		/* Case A: Deleted in one */
 +		if ((!a_sha && !b_sha) ||
 +		    (sha_eq(a_sha, o_sha) && !b_sha) ||
 +		    (!a_sha && sha_eq(b_sha, o_sha))) {
 +			/* Deleted in both or deleted in one and
 +			 * unchanged in the other */
 +			if (a_sha)
 +				output(2, "Removed %s", path);
 +			/* do not touch working file if it did not exist */
 +			remove_file(1, path, !a_sha);
 +		} else {
 +			/* Deleted in one and changed in the other */
 +			clean_merge = 0;
 +			if (!a_sha) {
 +				output(1, "CONFLICT (delete/modify): %s deleted in %s "
 +				       "and modified in %s. Version %s of %s left in tree.",
 +				       path, branch1,
 +				       branch2, branch2, path);
 +				update_file(0, b_sha, b_mode, path);
 +			} else {
 +				output(1, "CONFLICT (delete/modify): %s deleted in %s "
 +				       "and modified in %s. Version %s of %s left in tree.",
 +				       path, branch2,
 +				       branch1, branch1, path);
 +				update_file(0, a_sha, a_mode, path);
 +			}
 +		}
 +
 +	} else if ((!o_sha && a_sha && !b_sha) ||
 +		   (!o_sha && !a_sha && b_sha)) {
 +		/* Case B: Added in one. */
 +		const char *add_branch;
 +		const char *other_branch;
 +		unsigned mode;
 +		const unsigned char *sha;
 +		const char *conf;
 +
 +		if (a_sha) {
 +			add_branch = branch1;
 +			other_branch = branch2;
 +			mode = a_mode;
 +			sha = a_sha;
 +			conf = "file/directory";
 +		} else {
 +			add_branch = branch2;
 +			other_branch = branch1;
 +			mode = b_mode;
 +			sha = b_sha;
 +			conf = "directory/file";
 +		}
 +		if (path_list_has_path(&current_directory_set, path)) {
 +			const char *new_path = unique_path(path, add_branch);
 +			clean_merge = 0;
 +			output(1, "CONFLICT (%s): There is a directory with name %s in %s. "
 +			       "Added %s as %s",
 +			       conf, path, other_branch, path, new_path);
 +			remove_file(0, path, 0);
 +			update_file(0, sha, mode, new_path);
 +		} else {
 +			output(2, "Added %s", path);
 +			update_file(1, sha, mode, path);
 +		}
 +	} else if (a_sha && b_sha) {
 +		/* Case C: Added in both (check for same permissions) and */
 +		/* case D: Modified in both, but differently. */
 +		const char *reason = "content";
 +		struct merge_file_info mfi;
 +		struct diff_filespec o, a, b;
 +
 +		if (!o_sha) {
 +			reason = "add/add";
 +			o_sha = (unsigned char *)null_sha1;
 +		}
 +		output(2, "Auto-merged %s", path);
 +		o.path = a.path = b.path = (char *)path;
 +		hashcpy(o.sha1, o_sha);
 +		o.mode = o_mode;
 +		hashcpy(a.sha1, a_sha);
 +		a.mode = a_mode;
 +		hashcpy(b.sha1, b_sha);
 +		b.mode = b_mode;
 +
 +		mfi = merge_file(&o, &a, &b,
 +				 branch1, branch2);
 +
 +		clean_merge = mfi.clean;
 +		if (mfi.clean)
 +			update_file(1, mfi.sha, mfi.mode, path);
 +		else if (S_ISGITLINK(mfi.mode))
 +			output(1, "CONFLICT (submodule): Merge conflict in %s "
 +			       "- needs %s", path, sha1_to_hex(b.sha1));
 +		else {
 +			output(1, "CONFLICT (%s): Merge conflict in %s",
 +					reason, path);
 +
 +			if (index_only)
 +				update_file(0, mfi.sha, mfi.mode, path);
 +			else
 +				update_file_flags(mfi.sha, mfi.mode, path,
 +					      0 /* update_cache */, 1 /* update_working_directory */);
 +		}
 +	} else if (!o_sha && !a_sha && !b_sha) {
 +		/*
 +		 * this entry was deleted altogether. a_mode == 0 means
 +		 * we had that path and want to actively remove it.
 +		 */
 +		remove_file(1, path, !a_mode);
 +	} else
 +		die("Fatal merge failure, shouldn't happen.");
 +
 +	return clean_merge;
 +}
 +
 +int merge_trees(struct tree *head,
 +		struct tree *merge,
 +		struct tree *common,
 +		const char *branch1,
 +		const char *branch2,
 +		struct tree **result)
 +{
 +	int code, clean;
 +
 +	if (subtree_merge) {
 +		merge = shift_tree_object(head, merge);
 +		common = shift_tree_object(head, common);
 +	}
 +
 +	if (sha_eq(common->object.sha1, merge->object.sha1)) {
 +		output(0, "Already uptodate!");
 +		*result = head;
 +		return 1;
 +	}
 +
 +	code = git_merge_trees(index_only, common, head, merge);
 +
 +	if (code != 0)
 +		die("merging of trees %s and %s failed",
 +		    sha1_to_hex(head->object.sha1),
 +		    sha1_to_hex(merge->object.sha1));
 +
 +	if (unmerged_cache()) {
 +		struct path_list *entries, *re_head, *re_merge;
 +		int i;
 +		path_list_clear(&current_file_set, 1);
 +		path_list_clear(&current_directory_set, 1);
 +		get_files_dirs(head);
 +		get_files_dirs(merge);
 +
 +		entries = get_unmerged();
 +		re_head  = get_renames(head, common, head, merge, entries);
 +		re_merge = get_renames(merge, common, head, merge, entries);
 +		clean = process_renames(re_head, re_merge,
 +				branch1, branch2);
 +		for (i = 0; i < entries->nr; i++) {
 +			const char *path = entries->items[i].path;
 +			struct stage_data *e = entries->items[i].util;
 +			if (!e->processed
 +				&& !process_entry(path, e, branch1, branch2))
 +				clean = 0;
 +		}
 +
 +		path_list_clear(re_merge, 0);
 +		path_list_clear(re_head, 0);
 +		path_list_clear(entries, 1);
 +
 +	}
 +	else
 +		clean = 1;
 +
 +	if (index_only)
 +		*result = write_tree_from_memory();
 +
 +	return clean;
 +}
 +
 +static struct commit_list *reverse_commit_list(struct commit_list *list)
 +{
 +	struct commit_list *next = NULL, *current, *backup;
 +	for (current = list; current; current = backup) {
 +		backup = current->next;
 +		current->next = next;
 +		next = current;
 +	}
 +	return next;
 +}
 +
 +/*
 + * Merge the commits h1 and h2, return the resulting virtual
 + * commit object and a flag indicating the cleanness of the merge.
 + */
 +int merge_recursive(struct commit *h1,
 +		    struct commit *h2,
 +		    const char *branch1,
 +		    const char *branch2,
 +		    struct commit_list *ca,
 +		    struct commit **result)
 +{
 +	struct commit_list *iter;
 +	struct commit *merged_common_ancestors;
 +	struct tree *mrtree = mrtree;
 +	int clean;
 +
 +	if (show(4)) {
 +		output(4, "Merging:");
 +		output_commit_title(h1);
 +		output_commit_title(h2);
 +	}
 +
 +	if (!ca) {
 +		ca = get_merge_bases(h1, h2, 1);
 +		ca = reverse_commit_list(ca);
 +	}
 +
 +	if (show(5)) {
 +		output(5, "found %u common ancestor(s):", commit_list_count(ca));
 +		for (iter = ca; iter; iter = iter->next)
 +			output_commit_title(iter->item);
 +	}
 +
 +	merged_common_ancestors = pop_commit(&ca);
 +	if (merged_common_ancestors == NULL) {
 +		/* if there is no common ancestor, make an empty tree */
 +		struct tree *tree = xcalloc(1, sizeof(struct tree));
 +
 +		tree->object.parsed = 1;
 +		tree->object.type = OBJ_TREE;
 +		pretend_sha1_file(NULL, 0, OBJ_TREE, tree->object.sha1);
 +		merged_common_ancestors = make_virtual_commit(tree, "ancestor");
 +	}
 +
 +	for (iter = ca; iter; iter = iter->next) {
 +		call_depth++;
 +		/*
 +		 * When the merge fails, the result contains files
 +		 * with conflict markers. The cleanness flag is
 +		 * ignored, it was never actually used, as result of
 +		 * merge_trees has always overwritten it: the committed
 +		 * "conflicts" were already resolved.
 +		 */
 +		discard_cache();
 +		merge_recursive(merged_common_ancestors, iter->item,
 +				"Temporary merge branch 1",
 +				"Temporary merge branch 2",
 +				NULL,
 +				&merged_common_ancestors);
 +		call_depth--;
 +
 +		if (!merged_common_ancestors)
 +			die("merge returned no commit");
 +	}
 +
 +	discard_cache();
 +	if (!call_depth) {
 +		read_cache();
 +		index_only = 0;
 +	} else
 +		index_only = 1;
 +
 +	clean = merge_trees(h1->tree, h2->tree, merged_common_ancestors->tree,
 +			    branch1, branch2, &mrtree);
 +
 +	if (index_only) {
 +		*result = make_virtual_commit(mrtree, "merged tree");
 +		commit_list_insert(h1, &(*result)->parents);
 +		commit_list_insert(h2, &(*result)->parents->next);
 +	}
 +	flush_output();
 +	return clean;
 +}
 +
 +static const char *better_branch_name(const char *branch)
 +{
 +	static char githead_env[8 + 40 + 1];
 +	char *name;
 +
 +	if (strlen(branch) != 40)
 +		return branch;
 +	sprintf(githead_env, "GITHEAD_%s", branch);
 +	name = getenv(githead_env);
 +	return name ? name : branch;
 +}
 +
 +static struct commit *get_ref(const char *ref)
 +{
 +	unsigned char sha1[20];
 +	struct object *object;
 +
 +	if (get_sha1(ref, sha1))
 +		die("Could not resolve ref '%s'", ref);
 +	object = deref_tag(parse_object(sha1), ref, strlen(ref));
 +	if (!object)
 +		return NULL;
 +	if (object->type == OBJ_TREE)
 +		return make_virtual_commit((struct tree*)object,
 +			better_branch_name(ref));
 +	if (object->type != OBJ_COMMIT)
 +		return NULL;
 +	if (parse_commit((struct commit *)object))
 +		die("Could not parse commit '%s'", sha1_to_hex(object->sha1));
 +	return (struct commit *)object;
 +}
 +
 +static int merge_config(const char *var, const char *value)
 +{
 +	if (!strcasecmp(var, "merge.verbosity")) {
 +		verbosity = git_config_int(var, value);
 +		return 0;
 +	}
 +	if (!strcasecmp(var, "diff.renamelimit")) {
 +		rename_limit = git_config_int(var, value);
 +		return 0;
 +	}
 +	return git_default_config(var, value);
 +}
 +
 +int cmd_merge_recursive(int argc, const char **argv, const char *prefix)
 +{
 +	static const char *bases[20];
 +	static unsigned bases_count = 0;
 +	int i, clean;
 +	const char *branch1, *branch2;
 +	struct commit *result, *h1, *h2;
 +	struct commit_list *ca = NULL;
 +	struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
 +	int index_fd;
 +
 +	if (argv[0]) {
 +		int namelen = strlen(argv[0]);
 +		if (8 < namelen &&
 +		    !strcmp(argv[0] + namelen - 8, "-subtree"))
 +			subtree_merge = 1;
 +	}
 +
 +	git_config(merge_config);
 +	if (getenv("GIT_MERGE_VERBOSITY"))
 +		verbosity = strtol(getenv("GIT_MERGE_VERBOSITY"), NULL, 10);
 +
 +	if (argc < 4)
 +		die("Usage: %s <base>... -- <head> <remote> ...\n", argv[0]);
 +
 +	for (i = 1; i < argc; ++i) {
 +		if (!strcmp(argv[i], "--"))
 +			break;
 +		if (bases_count < sizeof(bases)/sizeof(*bases))
 +			bases[bases_count++] = argv[i];
 +	}
 +	if (argc - i != 3) /* "--" "<head>" "<remote>" */
 +		die("Not handling anything other than two heads merge.");
 +	if (verbosity >= 5)
 +		buffer_output = 0;
 +
 +	branch1 = argv[++i];
 +	branch2 = argv[++i];
 +
 +	h1 = get_ref(branch1);
 +	h2 = get_ref(branch2);
 +
 +	branch1 = better_branch_name(branch1);
 +	branch2 = better_branch_name(branch2);
 +
 +	if (show(3))
 +		printf("Merging %s with %s\n", branch1, branch2);
 +
 +	index_fd = hold_locked_index(lock, 1);
 +
 +	for (i = 0; i < bases_count; i++) {
 +		struct commit *ancestor = get_ref(bases[i]);
 +		ca = commit_list_insert(ancestor, &ca);
 +	}
 +	clean = merge_recursive(h1, h2, branch1, branch2, ca, &result);
 +
 +	if (active_cache_changed &&
 +	    (write_cache(index_fd, active_cache, active_nr) ||
 +	     commit_locked_index(lock)))
 +			die ("unable to write %s", get_index_file());
 +
 +	return clean ? 0: 1;
 +}