X-Git-Url: https://git.tokkee.org/?a=blobdiff_plain;f=merge-recursive.c;h=fa320eb6b1a9e257167e7f843fe36cbdfd908726;hb=717d1462ba0ebc430775eccaae65eb9b8234eb32;hp=611cd95cf597b0ccf06cf9b4318eb34a86a4c05a;hpb=284fe4beb6b4835ef6857cd56b34c70c1d12b14d;p=git.git

diff --git a/merge-recursive.c b/merge-recursive.c
index 611cd95cf..fa320eb6b 100644
--- a/merge-recursive.c
+++ b/merge-recursive.c
@@ -3,13 +3,6 @@
  * Fredrik Kuivinen.
  * The thieves were Alex Riesen and Johannes Schindelin, in June/July 2006
  */
-#include <stdarg.h>
-#include <string.h>
-#include <assert.h>
-#include <sys/wait.h>
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <time.h>
 #include "cache.h"
 #include "cache-tree.h"
 #include "commit.h"
@@ -21,6 +14,7 @@
 #include "tag.h"
 #include "unpack-trees.h"
 #include "path-list.h"
+#include "xdiff-interface.h"
 
 /*
  * A virtual commit has
@@ -73,32 +67,80 @@ struct stage_data
 	unsigned processed:1;
 };
 
+struct output_buffer
+{
+	struct output_buffer *next;
+	char *str;
+};
+
 static struct path_list current_file_set = {NULL, 0, 0, 1};
 static struct path_list current_directory_set = {NULL, 0, 0, 1};
 
-static int output_indent = 0;
+static int call_depth = 0;
+static int verbosity = 2;
+static int buffer_output = 1;
+static int do_progress = 1;
+static unsigned last_percent;
+static unsigned merged_cnt;
+static unsigned total_cnt;
+static volatile sig_atomic_t progress_update;
+static struct output_buffer *output_list, *output_end;
+
+static int show (int v)
+{
+	return (!call_depth && verbosity >= v) || verbosity >= 5;
+}
 
-static void output(const char *fmt, ...)
+static void output(int v, const char *fmt, ...)
 {
 	va_list args;
-	int i;
-	for (i = output_indent; i--;)
-		fputs("  ", stdout);
 	va_start(args, fmt);
-	vfprintf(stdout, fmt, args);
+	if (buffer_output && show(v)) {
+		struct output_buffer *b = xmalloc(sizeof(*b));
+		nfvasprintf(&b->str, fmt, args);
+		b->next = NULL;
+		if (output_end)
+			output_end->next = b;
+		else
+			output_list = b;
+		output_end = b;
+	} else if (show(v)) {
+		int i;
+		for (i = call_depth; i--;)
+			fputs("  ", stdout);
+		vfprintf(stdout, fmt, args);
+		fputc('\n', stdout);
+	}
 	va_end(args);
-	fputc('\n', stdout);
+}
+
+static void flush_output()
+{
+	struct output_buffer *b, *n;
+	for (b = output_list; b; b = n) {
+		int i;
+		for (i = call_depth; i--;)
+			fputs("  ", stdout);
+		fputs(b->str, stdout);
+		fputc('\n', stdout);
+		n = b->next;
+		free(b->str);
+		free(b);
+	}
+	output_list = NULL;
+	output_end = NULL;
 }
 
 static void output_commit_title(struct commit *commit)
 {
 	int i;
-	for (i = output_indent; i--;)
+	flush_output();
+	for (i = call_depth; i--;)
 		fputs("  ", stdout);
 	if (commit->util)
 		printf("virtual %s\n", (char *)commit->util);
 	else {
-		printf("%s ", sha1_to_hex(commit->object.sha1));
+		printf("%s ", find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV));
 		if (parse_commit(commit) != 0)
 			printf("(bad commit)\n");
 		else {
@@ -116,33 +158,37 @@ static void output_commit_title(struct commit *commit)
 	}
 }
 
-static const char *current_index_file = NULL;
-static const char *original_index_file;
-static const char *temporary_index_file;
-static int cache_dirty = 0;
+static void progress_interval(int signum)
+{
+	progress_update = 1;
+}
 
-static int flush_cache(void)
+static void setup_progress_signal(void)
 {
-	/* flush temporary index */
-	struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
-	int fd = hold_lock_file_for_update(lock, current_index_file, 1);
-	if (write_cache(fd, active_cache, active_nr) ||
-			close(fd) || commit_lock_file(lock))
-		die ("unable to write %s", current_index_file);
-	discard_cache();
-	cache_dirty = 0;
-	return 0;
+	struct sigaction sa;
+	struct itimerval v;
+
+	memset(&sa, 0, sizeof(sa));
+	sa.sa_handler = progress_interval;
+	sigemptyset(&sa.sa_mask);
+	sa.sa_flags = SA_RESTART;
+	sigaction(SIGALRM, &sa, NULL);
+
+	v.it_interval.tv_sec = 1;
+	v.it_interval.tv_usec = 0;
+	v.it_value = v.it_interval;
+	setitimer(ITIMER_REAL, &v, NULL);
 }
 
-static void setup_index(int temp)
+static void display_progress()
 {
-	current_index_file = temp ? temporary_index_file: original_index_file;
-	if (cache_dirty) {
-		discard_cache();
-		cache_dirty = 0;
+	unsigned percent = total_cnt ? merged_cnt * 100 / total_cnt : 0;
+	if (progress_update || percent != last_percent) {
+		fprintf(stderr, "%4u%% (%u/%u) done\r",
+			percent, merged_cnt, total_cnt);
+		progress_update = 0;
+		last_percent = percent;
 	}
-	unlink(temporary_index_file);
-	discard_cache();
 }
 
 static struct cache_entry *make_cache_entry(unsigned int mode,
@@ -173,9 +219,6 @@ static int add_cacheinfo(unsigned int mode, const unsigned char *sha1,
 		const char *path, int stage, int refresh, int options)
 {
 	struct cache_entry *ce;
-	if (!cache_dirty)
-		read_cache_from(current_index_file);
-	cache_dirty++;
 	ce = make_cache_entry(mode, sha1 ? sha1 : null_sha1, path, stage, refresh);
 	if (!ce)
 		return error("cache_addinfo failed: %s", strerror(cache_errno));
@@ -193,26 +236,6 @@ static int add_cacheinfo(unsigned int mode, const unsigned char *sha1,
  */
 static int index_only = 0;
 
-static int git_read_tree(struct tree *tree)
-{
-	int rc;
-	struct object_list *trees = NULL;
-	struct unpack_trees_options opts;
-
-	if (cache_dirty)
-		die("read-tree with dirty cache");
-
-	memset(&opts, 0, sizeof(opts));
-	object_list_append(&tree->object, &trees);
-	rc = unpack_trees(trees, &opts);
-	cache_tree_free(&active_cache_tree);
-
-	if (rc == 0)
-		cache_dirty = 1;
-
-	return rc;
-}
-
 static int git_merge_trees(int index_only,
 			   struct tree *common,
 			   struct tree *head,
@@ -222,11 +245,6 @@ static int git_merge_trees(int index_only,
 	struct object_list *trees = NULL;
 	struct unpack_trees_options opts;
 
-	if (!cache_dirty) {
-		read_cache_from(current_index_file);
-		cache_dirty = 1;
-	}
-
 	memset(&opts, 0, sizeof(opts));
 	if (index_only)
 		opts.index_only = 1;
@@ -242,39 +260,37 @@ static int git_merge_trees(int index_only,
 
 	rc = unpack_trees(trees, &opts);
 	cache_tree_free(&active_cache_tree);
-
-	cache_dirty = 1;
-
 	return rc;
 }
 
+static int unmerged_index(void)
+{
+	int i;
+	for (i = 0; i < active_nr; i++) {
+		struct cache_entry *ce = active_cache[i];
+		if (ce_stage(ce))
+			return 1;
+	}
+	return 0;
+}
+
 static struct tree *git_write_tree(void)
 {
 	struct tree *result = NULL;
 
-	if (cache_dirty) {
-		unsigned i;
-		for (i = 0; i < active_nr; i++) {
-			struct cache_entry *ce = active_cache[i];
-			if (ce_stage(ce))
-				return NULL;
-		}
-	} else
-		read_cache_from(current_index_file);
+	if (unmerged_index())
+		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)
+	    cache_tree_update(active_cache_tree,
+			      active_cache, active_nr, 0, 0) < 0)
 		die("error building trees");
 
 	result = lookup_tree(active_cache_tree->sha1);
 
-	flush_cache();
-	cache_dirty = 0;
-
 	return result;
 }
 
@@ -337,14 +353,14 @@ static struct path_list *get_unmerged(void)
 	int i;
 
 	unmerged->strdup_paths = 1;
-	if (!cache_dirty) {
-		read_cache_from(current_index_file);
-		cache_dirty++;
-	}
-	for (i = 0; i < active_nr; i++) {
+	total_cnt += active_nr;
+
+	for (i = 0; i < active_nr; i++, merged_cnt++) {
 		struct path_list_item *item;
 		struct stage_data *e;
 		struct cache_entry *ce = active_cache[i];
+		if (do_progress)
+			display_progress();
 		if (!ce_stage(ce))
 			continue;
 
@@ -427,8 +443,9 @@ static struct path_list *get_renames(struct tree *tree,
 	return renames;
 }
 
-int update_stages(const char *path, struct diff_filespec *o,
-		struct diff_filespec *a, struct diff_filespec *b, int clear)
+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)
@@ -468,20 +485,16 @@ static int remove_path(const char *name)
 	return ret;
 }
 
-int remove_file(int clean, const char *path)
+static int remove_file(int clean, const char *path, int no_wd)
 {
 	int update_cache = index_only || clean;
-	int update_working_directory = !index_only;
+	int update_working_directory = !index_only && !no_wd;
 
 	if (update_cache) {
-		if (!cache_dirty)
-			read_cache_from(current_index_file);
-		cache_dirty++;
 		if (remove_file_from_cache(path))
 			return -1;
 	}
-	if (update_working_directory)
-	{
+	if (update_working_directory) {
 		unlink(path);
 		if (errno != ENOENT || errno != EISDIR)
 			return -1;
@@ -523,7 +536,7 @@ static int mkdir_p(const char *path, unsigned long mode)
 static void flush_buffer(int fd, const char *buf, unsigned long size)
 {
 	while (size > 0) {
-		long ret = xwrite(fd, buf, size);
+		long ret = write_in_full(fd, buf, size);
 		if (ret < 0) {
 			/* Ignore epipe */
 			if (errno == EPIPE)
@@ -537,11 +550,11 @@ static void flush_buffer(int fd, const char *buf, unsigned long size)
 	}
 }
 
-void update_file_flags(const unsigned char *sha,
-		       unsigned mode,
-		       const char *path,
-		       int update_cache,
-		       int update_wd)
+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;
@@ -586,10 +599,10 @@ void update_file_flags(const unsigned char *sha,
 		add_cacheinfo(mode, sha, path, 0, update_wd, ADD_CACHE_OK_TO_ADD);
 }
 
-void update_file(int clean,
-		const unsigned char *sha,
-		unsigned mode,
-		const char *path)
+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);
 }
@@ -604,24 +617,21 @@ struct merge_file_info
 		 merge:1;
 };
 
-static char *git_unpack_file(const unsigned char *sha1, char *path)
+static void fill_mm(const unsigned char *sha1, mmfile_t *mm)
 {
-	void *buf;
-	char type[20];
 	unsigned long size;
-	int fd;
+	char type[20];
 
-	buf = read_sha1_file(sha1, type, &size);
-	if (!buf || strcmp(type, blob_type))
-		die("unable to read blob object %s", sha1_to_hex(sha1));
+	if (!hashcmp(sha1, null_sha1)) {
+		mm->ptr = xstrdup("");
+		mm->size = 0;
+		return;
+	}
 
-	strcpy(path, ".merge_file_XXXXXX");
-	fd = mkstemp(path);
-	if (fd < 0)
-		die("unable to create temp-file");
-	flush_buffer(fd, buf, size);
-	close(fd);
-	return path;
+	mm->ptr = read_sha1_file(sha1, type, &size);
+	if (!mm->ptr || strcmp(type, blob_type))
+		die("unable to read blob object %s", sha1_to_hex(sha1));
+	mm->size = size;
 }
 
 static struct merge_file_info merge_file(struct diff_filespec *o,
@@ -652,49 +662,41 @@ static struct merge_file_info merge_file(struct diff_filespec *o,
 		else if (sha_eq(b->sha1, o->sha1))
 			hashcpy(result.sha, a->sha1);
 		else if (S_ISREG(a->mode)) {
-			int code = 1, fd;
-			struct stat st;
-			char orig[PATH_MAX];
-			char src1[PATH_MAX];
-			char src2[PATH_MAX];
-			const char *argv[] = {
-				"merge", "-L", NULL, "-L", NULL, "-L", NULL,
-				NULL, NULL, NULL,
-				NULL
-			};
-			char *la, *lb, *lo;
-
-			git_unpack_file(o->sha1, orig);
-			git_unpack_file(a->sha1, src1);
-			git_unpack_file(b->sha1, src2);
-
-			argv[2] = la = xstrdup(mkpath("%s/%s", branch1, a->path));
-			argv[6] = lb = xstrdup(mkpath("%s/%s", branch2, b->path));
-			argv[4] = lo = xstrdup(mkpath("orig/%s", o->path));
-			argv[7] = src1;
-			argv[8] = orig;
-			argv[9] = src2,
-
-			code = run_command_v(10, argv);
-
-			free(la);
-			free(lb);
-			free(lo);
-			if (code && code < -256) {
-				die("Failed to execute 'merge'. merge(1) is used as the "
-				    "file-level merge tool. Is 'merge' in your path?");
-			}
-			fd = open(src1, O_RDONLY);
-			if (fd < 0 || fstat(fd, &st) < 0 ||
-					index_fd(result.sha, fd, &st, 1,
-						"blob"))
-				die("Unable to add %s to database", src1);
-
-			unlink(orig);
-			unlink(src1);
-			unlink(src2);
-
-			result.clean = WEXITSTATUS(code) == 0;
+			mmfile_t orig, src1, src2;
+			mmbuffer_t result_buf;
+			xpparam_t xpp;
+			char *name1, *name2;
+			int merge_status;
+
+			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);
+
+			memset(&xpp, 0, sizeof(xpp));
+			merge_status = xdl_merge(&orig,
+						 &src1, name1,
+						 &src2, name2,
+						 &xpp, XDL_MERGE_ZEALOUS,
+						 &result_buf);
+			free(name1);
+			free(name2);
+			free(orig.ptr);
+			free(src1.ptr);
+			free(src2.ptr);
+
+			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_ISLNK(a->mode) || S_ISLNK(b->mode)))
 				die("cannot merge modes?");
@@ -722,15 +724,15 @@ static void conflict_rename_rename(struct rename *ren1,
 	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("%s is a directory in %s adding as %s instead",
+		output(1, "%s is a directory in %s added as %s instead",
 		       ren1_dst, branch2, dst_name1);
-		remove_file(0, ren1_dst);
+		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("%s is a directory in %s adding as %s instead",
+		output(1, "%s is a directory in %s added as %s instead",
 		       ren2_dst, branch1, dst_name2);
-		remove_file(0, ren2_dst);
+		remove_file(0, ren2_dst, 0);
 	}
 	update_stages(dst_name1, NULL, ren1->pair->two, NULL, 1);
 	update_stages(dst_name2, NULL, NULL, ren2->pair->two, 1);
@@ -742,8 +744,8 @@ static void conflict_rename_dir(struct rename *ren1,
 				const char *branch1)
 {
 	char *new_path = unique_path(ren1->pair->two->path, branch1);
-	output("Renaming %s to %s instead", ren1->pair->one->path, new_path);
-	remove_file(0, ren1->pair->two->path);
+	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);
 }
@@ -755,10 +757,10 @@ static void conflict_rename_rename_2(struct rename *ren1,
 {
 	char *new_path1 = unique_path(ren1->pair->two->path, branch1);
 	char *new_path2 = unique_path(ren2->pair->two->path, branch2);
-	output("Renaming %s to %s and %s to %s instead",
+	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);
+	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);
@@ -848,7 +850,7 @@ static int process_renames(struct path_list *a_renames,
 			ren2->processed = 1;
 			if (strcmp(ren1_dst, ren2_dst) != 0) {
 				clean_merge = 0;
-				output("CONFLICT (rename/rename): "
+				output(1, "CONFLICT (rename/rename): "
 				       "Rename %s->%s in branch %s "
 				       "rename %s->%s in %s",
 				       src, ren1_dst, branch1,
@@ -856,20 +858,20 @@ static int process_renames(struct path_list *a_renames,
 				conflict_rename_rename(ren1, branch1, ren2, branch2);
 			} else {
 				struct merge_file_info mfi;
-				remove_file(1, ren1_src);
+				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("Renaming %s->%s", src, ren1_dst);
+					output(1, "Renamed %s->%s", src, ren1_dst);
 
 				if (mfi.merge)
-					output("Auto-merging %s", ren1_dst);
+					output(2, "Auto-merged %s", ren1_dst);
 
 				if (!mfi.clean) {
-					output("CONFLICT (content): merge conflict in %s",
+					output(1, "CONFLICT (content): merge conflict in %s",
 					       ren1_dst);
 					clean_merge = 0;
 
@@ -889,7 +891,7 @@ static int process_renames(struct path_list *a_renames,
 			struct diff_filespec src_other, dst_other;
 			int try_merge, stage = a_renames == renames1 ? 3: 2;
 
-			remove_file(1, ren1_src);
+			remove_file(1, ren1_src, index_only);
 
 			hashcpy(src_other.sha1, ren1->src_entry->stages[stage].sha);
 			src_other.mode = ren1->src_entry->stages[stage].mode;
@@ -900,14 +902,14 @@ static int process_renames(struct path_list *a_renames,
 
 			if (path_list_has_path(&current_directory_set, ren1_dst)) {
 				clean_merge = 0;
-				output("CONFLICT (rename/directory): Rename %s->%s in %s "
+				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("CONFLICT (rename/delete): Rename %s->%s in %s "
+				output(1, "CONFLICT (rename/delete): Renamed %s->%s in %s "
 				       "and deleted in %s",
 				       ren1_src, ren1_dst, branch1,
 				       branch2);
@@ -916,19 +918,19 @@ static int process_renames(struct path_list *a_renames,
 				const char *new_path;
 				clean_merge = 0;
 				try_merge = 1;
-				output("CONFLICT (rename/add): Rename %s->%s in %s. "
+				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("Adding as %s instead", new_path);
+				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("CONFLICT (rename/rename): Rename %s->%s in %s. "
-				       "Rename %s->%s in %s",
+				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);
@@ -952,11 +954,11 @@ static int process_renames(struct path_list *a_renames,
 						a_branch, b_branch);
 
 				if (mfi.merge || !mfi.clean)
-					output("Renaming %s => %s", ren1_src, ren1_dst);
+					output(1, "Renamed %s => %s", ren1_src, ren1_dst);
 				if (mfi.merge)
-					output("Auto-merging %s", ren1_dst);
+					output(2, "Auto-merged %s", ren1_dst);
 				if (!mfi.clean) {
-					output("CONFLICT (rename/modify): Merge conflict in %s",
+					output(1, "CONFLICT (rename/modify): Merge conflict in %s",
 					       ren1_dst);
 					clean_merge = 0;
 
@@ -971,8 +973,6 @@ static int process_renames(struct path_list *a_renames,
 	path_list_clear(&a_by_dst, 0);
 	path_list_clear(&b_by_dst, 0);
 
-	if (cache_dirty)
-		flush_cache();
 	return clean_merge;
 }
 
@@ -1006,19 +1006,20 @@ static int process_entry(const char *path, struct stage_data *entry,
 			/* Deleted in both or deleted in one and
 			 * unchanged in the other */
 			if (a_sha)
-				output("Removing %s", path);
-			remove_file(1, path);
+				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("CONFLICT (delete/modify): %s deleted in %s "
+				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("CONFLICT (delete/modify): %s deleted in %s "
+				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);
@@ -1051,48 +1052,27 @@ static int process_entry(const char *path, struct stage_data *entry,
 		if (path_list_has_path(&current_directory_set, path)) {
 			const char *new_path = unique_path(path, add_branch);
 			clean_merge = 0;
-			output("CONFLICT (%s): There is a directory with name %s in %s. "
-			       "Adding %s as %s",
+			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);
+			remove_file(0, path, 0);
 			update_file(0, sha, mode, new_path);
 		} else {
-			output("Adding %s", path);
+			output(2, "Added %s", path);
 			update_file(1, sha, mode, path);
 		}
-	} else if (!o_sha && a_sha && b_sha) {
-		/* Case C: Added in both (check for same permissions). */
-		if (sha_eq(a_sha, b_sha)) {
-			if (a_mode != b_mode) {
-				clean_merge = 0;
-				output("CONFLICT: File %s added identically in both branches, "
-				       "but permissions conflict %06o->%06o",
-				       path, a_mode, b_mode);
-				output("CONFLICT: adding with permission: %06o", a_mode);
-				update_file(0, a_sha, a_mode, path);
-			} else {
-				/* This case is handled by git-read-tree */
-				assert(0 && "This case must be handled by git-read-tree");
-			}
-		} else {
-			const char *new_path1, *new_path2;
-			clean_merge = 0;
-			new_path1 = unique_path(path, branch1);
-			new_path2 = unique_path(path, branch2);
-			output("CONFLICT (add/add): File %s added non-identically "
-			       "in both branches. Adding as %s and %s instead.",
-			       path, new_path1, new_path2);
-			remove_file(0, path);
-			update_file(0, a_sha, a_mode, new_path1);
-			update_file(0, b_sha, b_mode, new_path2);
-		}
-
-	} else if (o_sha && a_sha && b_sha) {
+	} 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;
 
-		output("Auto-merging %s", path);
+		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;
@@ -1108,7 +1088,8 @@ static int process_entry(const char *path, struct stage_data *entry,
 			update_file(1, mfi.sha, mfi.mode, path);
 		else {
 			clean_merge = 0;
-			output("CONFLICT (content): Merge conflict in %s", path);
+			output(1, "CONFLICT (%s): Merge conflict in %s",
+					reason, path);
 
 			if (index_only)
 				update_file(0, mfi.sha, mfi.mode, path);
@@ -1119,9 +1100,6 @@ static int process_entry(const char *path, struct stage_data *entry,
 	} else
 		die("Fatal merge failure, shouldn't happen.");
 
-	if (cache_dirty)
-		flush_cache();
-
 	return clean_merge;
 }
 
@@ -1134,7 +1112,7 @@ static int merge_trees(struct tree *head,
 {
 	int code, clean;
 	if (sha_eq(common->object.sha1, merge->object.sha1)) {
-		output("Already uptodate!");
+		output(0, "Already uptodate!");
 		*result = head;
 		return 1;
 	}
@@ -1146,9 +1124,7 @@ static int merge_trees(struct tree *head,
 		    sha1_to_hex(head->object.sha1),
 		    sha1_to_hex(merge->object.sha1));
 
-	*result = git_write_tree();
-
-	if (!*result) {
+	if (unmerged_index()) {
 		struct path_list *entries, *re_head, *re_merge;
 		int i;
 		path_list_clear(&current_file_set, 1);
@@ -1161,30 +1137,27 @@ static int merge_trees(struct tree *head,
 		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++) {
+		total_cnt += entries->nr;
+		for (i = 0; i < entries->nr; i++, merged_cnt++) {
 			const char *path = entries->items[i].path;
 			struct stage_data *e = entries->items[i].util;
-			if (e->processed)
-				continue;
-			if (!process_entry(path, e, branch1, branch2))
+			if (!e->processed
+				&& !process_entry(path, e, branch1, branch2))
 				clean = 0;
+			if (do_progress)
+				display_progress();
 		}
 
 		path_list_clear(re_merge, 0);
 		path_list_clear(re_head, 0);
 		path_list_clear(entries, 1);
 
-		if (clean || index_only)
-			*result = git_write_tree();
-		else
-			*result = NULL;
-	} else {
-		clean = 1;
-		printf("merging of trees %s and %s resulted in %s\n",
-		       sha1_to_hex(head->object.sha1),
-		       sha1_to_hex(merge->object.sha1),
-		       sha1_to_hex((*result)->object.sha1));
 	}
+	else
+		clean = 1;
+
+	if (index_only)
+		*result = git_write_tree();
 
 	return clean;
 }
@@ -1204,49 +1177,48 @@ static struct commit_list *reverse_commit_list(struct commit_list *list)
  * Merge the commits h1 and h2, return the resulting virtual
  * commit object and a flag indicating the cleaness of the merge.
  */
-static
-int merge(struct commit *h1,
-			  struct commit *h2,
-			  const char *branch1,
-			  const char *branch2,
-			  int call_depth /* =0 */,
-			  struct commit *ancestor /* =None */,
-			  struct commit **result)
+static int merge(struct commit *h1,
+		 struct commit *h2,
+		 const char *branch1,
+		 const char *branch2,
+		 struct commit_list *ca,
+		 struct commit **result)
 {
-	struct commit_list *ca = NULL, *iter;
+	struct commit_list *iter;
 	struct commit *merged_common_ancestors;
 	struct tree *mrtree;
 	int clean;
 
-	output("Merging:");
-	output_commit_title(h1);
-	output_commit_title(h2);
+	if (show(4)) {
+		output(4, "Merging:");
+		output_commit_title(h1);
+		output_commit_title(h2);
+	}
 
-	if (ancestor)
-		commit_list_insert(ancestor, &ca);
-	else
-		ca = reverse_commit_list(get_merge_bases(h1, h2, 1));
+	if (!ca) {
+		ca = get_merge_bases(h1, h2, 1);
+		ca = reverse_commit_list(ca);
+	}
 
-	output("found %u common ancestor(s):", commit_list_count(ca));
-	for (iter = ca; iter; iter = iter->next)
-		output_commit_title(iter->item);
+	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));
-		unsigned char hdr[40];
-		int hdrlen;
 
 		tree->object.parsed = 1;
 		tree->object.type = OBJ_TREE;
-		write_sha1_file_prepare(NULL, 0, tree_type, tree->object.sha1,
-					hdr, &hdrlen);
+		write_sha1_file(NULL, 0, tree_type, tree->object.sha1);
 		merged_common_ancestors = make_virtual_commit(tree, "ancestor");
 	}
 
 	for (iter = ca; iter; iter = iter->next) {
-		output_indent = call_depth + 1;
+		call_depth++;
 		/*
 		 * When the merge fails, the result contains files
 		 * with conflict markers. The cleanness flag is
@@ -1254,40 +1226,58 @@ int merge(struct commit *h1,
 		 * merge_trees has always overwritten it: the commited
 		 * "conflicts" were already resolved.
 		 */
+		discard_cache();
 		merge(merged_common_ancestors, iter->item,
 		      "Temporary merge branch 1",
 		      "Temporary merge branch 2",
-		      call_depth + 1,
 		      NULL,
 		      &merged_common_ancestors);
-		output_indent = call_depth;
+		call_depth--;
 
 		if (!merged_common_ancestors)
 			die("merge returned no commit");
 	}
 
-	if (call_depth == 0) {
-		setup_index(0 /* $GIT_DIR/index */);
+	discard_cache();
+	if (!call_depth) {
+		read_cache();
 		index_only = 0;
-	} else {
-		setup_index(1 /* temporary index */);
-		git_read_tree(h1->tree);
+	} else
 		index_only = 1;
-	}
 
 	clean = merge_trees(h1->tree, h2->tree, merged_common_ancestors->tree,
 			    branch1, branch2, &mrtree);
 
-	if (!ancestor && (clean || index_only)) {
+	if (index_only) {
 		*result = make_virtual_commit(mrtree, "merged tree");
 		commit_list_insert(h1, &(*result)->parents);
 		commit_list_insert(h2, &(*result)->parents->next);
-	} else
-		*result = NULL;
-
+	}
+	if (!call_depth && do_progress) {
+		/* Make sure we end at 100% */
+		if (!total_cnt)
+			total_cnt = 1;
+		merged_cnt = total_cnt;
+		progress_update = 1;
+		display_progress();
+		fputc('\n', stderr);
+	}
+	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];
@@ -1296,6 +1286,9 @@ static struct commit *get_ref(const char *ref)
 	if (get_sha1(ref, sha1))
 		die("Could not resolve ref '%s'", ref);
 	object = deref_tag(parse_object(sha1), ref, strlen(ref));
+	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))
@@ -1303,20 +1296,29 @@ static struct commit *get_ref(const char *ref)
 	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;
+	}
+	return git_default_config(var, value);
+}
+
 int main(int argc, char *argv[])
 {
-	static const char *bases[2];
+	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;
 
-	original_index_file = getenv("GIT_INDEX_FILE");
-
-	if (!original_index_file)
-		original_index_file = xstrdup(git_path("index"));
-
-	temporary_index_file = xstrdup(git_path("mrg-rcrsv-tmp-idx"));
+	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]);
@@ -1329,26 +1331,39 @@ int main(int argc, char *argv[])
 	}
 	if (argc - i != 3) /* "--" "<head>" "<remote>" */
 		die("Not handling anything other than two heads merge.");
+	if (verbosity >= 5) {
+		buffer_output = 0;
+		do_progress = 0;
+	}
+	else
+		do_progress = isatty(1);
 
 	branch1 = argv[++i];
 	branch2 = argv[++i];
-	printf("Merging %s with %s\n", branch1, branch2);
 
 	h1 = get_ref(branch1);
 	h2 = get_ref(branch2);
 
-	if (bases_count == 1) {
-		struct commit *ancestor = get_ref(bases[0]);
-		clean = merge(h1, h2, branch1, branch2, 0, ancestor, &result);
-	} else
-		clean = merge(h1, h2, branch1, branch2, 0, NULL, &result);
+	branch1 = better_branch_name(branch1);
+	branch2 = better_branch_name(branch2);
+
+	if (do_progress)
+		setup_progress_signal();
+	if (show(3))
+		printf("Merging %s with %s\n", branch1, branch2);
 
-	if (cache_dirty)
-		flush_cache();
+	index_fd = hold_lock_file_for_update(lock, get_index_file(), 1);
+
+	for (i = 0; i < bases_count; i++) {
+		struct commit *ancestor = get_ref(bases[i]);
+		ca = commit_list_insert(ancestor, &ca);
+	}
+	clean = merge(h1, h2, branch1, branch2, ca, &result);
+
+	if (active_cache_changed &&
+	    (write_cache(index_fd, active_cache, active_nr) ||
+	     close(index_fd) || commit_lock_file(lock)))
+			die ("unable to write %s", get_index_file());
 
 	return clean ? 0: 1;
 }
-
-/*
-vim: sw=8 noet
-*/