1 files changed, 210 insertions, 12 deletions

diff --git a/update-index.c b/update-index.c
index 1efac27c6b..3d7e02db2c 100644
--- a/update-index.c
+++ b/update-index.c
@@ -6,6 +6,7 @@
 #include "cache.h"
 #include "strbuf.h"
 #include "quote.h"
+#include "tree-walk.h"
 
 /*
  * Default to not allowing changes to the list of files. The
@@ -328,7 +329,7 @@ static int add_cacheinfo(unsigned int mode, const unsigned char *sha1,
 	return 0;
 }
 
-static int chmod_path(int flip, const char *path)
+static void chmod_path(int flip, const char *path)
 {
 	int pos;
 	struct cache_entry *ce;
@@ -336,21 +337,24 @@ static int chmod_path(int flip, const char *path)
 
 	pos = cache_name_pos(path, strlen(path));
 	if (pos < 0)
-		return -1;
+		goto fail;
 	ce = active_cache[pos];
 	mode = ntohl(ce->ce_mode);
 	if (!S_ISREG(mode))
-		return -1;
+		goto fail;
 	switch (flip) {
 	case '+':
 		ce->ce_mode |= htonl(0111); break;
 	case '-':
 		ce->ce_mode &= htonl(~0111); break;
 	default:
-		return -1;
+		goto fail;
 	}
 	active_cache_changed = 1;
-	return 0;
+	report("chmod %cx '%s'", flip, path);
+	return;
+ fail:
+	die("git-update-index: cannot chmod %cx '%s'", flip, path);
 }
 
 static struct cache_file cache_file;
@@ -360,23 +364,26 @@ static void update_one(const char *path, const char *prefix, int prefix_length)
 	const char *p = prefix_path(prefix, prefix_length, path);
 	if (!verify_path(p)) {
 		fprintf(stderr, "Ignoring path %s\n", path);
-		return;
+		goto free_return;
 	}
 	if (mark_valid_only) {
 		if (mark_valid(p))
 			die("Unable to mark file %s", path);
-		return;
+		goto free_return;
 	}
 
 	if (force_remove) {
 		if (remove_file_from_cache(p))
 			die("git-update-index: unable to remove %s", path);
 		report("remove '%s'", path);
-		return;
+		goto free_return;
 	}
 	if (add_file_to_cache(p))
 		die("Unable to process file %s", path);
 	report("add '%s'", path);
+ free_return:
+	if (p < path || p > path + strlen(path))
+		free((char*)p);
 }
 
 static void read_index_info(int line_termination)
@@ -469,7 +476,174 @@ static void read_index_info(int line_termination)
 }
 
 static const char update_index_usage[] =
-"git-update-index [-q] [--add] [--replace] [--remove] [--unmerged] [--refresh] [--cacheinfo] [--chmod=(+|-)x] [--info-only] [--force-remove] [--stdin] [--index-info] [--ignore-missing] [-z] [--verbose] [--] <file>...";
+"git-update-index [-q] [--add] [--replace] [--remove] [--unmerged] [--refresh] [--really-refresh] [--cacheinfo] [--chmod=(+|-)x] [--assume-unchanged] [--info-only] [--force-remove] [--stdin] [--index-info] [--unresolve] [--again] [--ignore-missing] [-z] [--verbose] [--] <file>...";
+
+static unsigned char head_sha1[20];
+static unsigned char merge_head_sha1[20];
+
+static struct cache_entry *read_one_ent(const char *which,
+					unsigned char *ent, const char *path,
+					int namelen, int stage)
+{
+	unsigned mode;
+	unsigned char sha1[20];
+	int size;
+	struct cache_entry *ce;
+
+	if (get_tree_entry(ent, path, sha1, &mode)) {
+		if (which)
+			error("%s: not in %s branch.", path, which);
+		return NULL;
+	}
+	if (mode == S_IFDIR) {
+		if (which)
+			error("%s: not a blob in %s branch.", path, which);
+		return NULL;
+	}
+	size = cache_entry_size(namelen);
+	ce = xcalloc(1, size);
+
+	memcpy(ce->sha1, sha1, 20);
+	memcpy(ce->name, path, namelen);
+	ce->ce_flags = create_ce_flags(namelen, stage);
+	ce->ce_mode = create_ce_mode(mode);
+	return ce;
+}
+
+static int unresolve_one(const char *path)
+{
+	int namelen = strlen(path);
+	int pos;
+	int ret = 0;
+	struct cache_entry *ce_2 = NULL, *ce_3 = NULL;
+
+	/* See if there is such entry in the index. */
+	pos = cache_name_pos(path, namelen);
+	if (pos < 0) {
+		/* If there isn't, either it is unmerged, or
+		 * resolved as "removed" by mistake.  We do not
+		 * want to do anything in the former case.
+		 */
+		pos = -pos-1;
+		if (pos < active_nr) {
+			struct cache_entry *ce = active_cache[pos];
+			if (ce_namelen(ce) == namelen &&
+			    !memcmp(ce->name, path, namelen)) {
+				fprintf(stderr,
+					"%s: skipping still unmerged path.\n",
+					path);
+				goto free_return;
+			}
+		}
+	}
+
+	/* Grab blobs from given path from HEAD and MERGE_HEAD,
+	 * stuff HEAD version in stage #2,
+	 * stuff MERGE_HEAD version in stage #3.
+	 */
+	ce_2 = read_one_ent("our", head_sha1, path, namelen, 2);
+	ce_3 = read_one_ent("their", merge_head_sha1, path, namelen, 3);
+
+	if (!ce_2 || !ce_3) {
+		ret = -1;
+		goto free_return;
+	}
+	if (!memcmp(ce_2->sha1, ce_3->sha1, 20) &&
+	    ce_2->ce_mode == ce_3->ce_mode) {
+		fprintf(stderr, "%s: identical in both, skipping.\n",
+			path);
+		goto free_return;
+	}
+
+	remove_file_from_cache(path);
+	if (add_cache_entry(ce_2, ADD_CACHE_OK_TO_ADD)) {
+		error("%s: cannot add our version to the index.", path);
+		ret = -1;
+		goto free_return;
+	}
+	if (!add_cache_entry(ce_3, ADD_CACHE_OK_TO_ADD))
+		return 0;
+	error("%s: cannot add their version to the index.", path);
+	ret = -1;
+ free_return:
+	free(ce_2);
+	free(ce_3);
+	return ret;
+}
+
+static void read_head_pointers(void)
+{
+	if (read_ref(git_path("HEAD"), head_sha1))
+		die("No HEAD -- no initial commit yet?\n");
+	if (read_ref(git_path("MERGE_HEAD"), merge_head_sha1)) {
+		fprintf(stderr, "Not in the middle of a merge.\n");
+		exit(0);
+	}
+}
+
+static int do_unresolve(int ac, const char **av,
+			const char *prefix, int prefix_length)
+{
+	int i;
+	int err = 0;
+
+	/* Read HEAD and MERGE_HEAD; if MERGE_HEAD does not exist, we
+	 * are not doing a merge, so exit with success status.
+	 */
+	read_head_pointers();
+
+	for (i = 1; i < ac; i++) {
+		const char *arg = av[i];
+		const char *p = prefix_path(prefix, prefix_length, arg);
+		err |= unresolve_one(p);
+		if (p < arg || p > arg + strlen(arg))
+			free((char*)p);
+	}
+	return err;
+}
+
+static int do_reupdate(int ac, const char **av,
+		       const char *prefix, int prefix_length)
+{
+	/* Read HEAD and run update-index on paths that are
+	 * merged and already different between index and HEAD.
+	 */
+	int pos;
+	int has_head = 1;
+	const char **pathspec = get_pathspec(prefix, av + 1);
+
+	if (read_ref(git_path("HEAD"), head_sha1))
+		/* If there is no HEAD, that means it is an initial
+		 * commit.  Update everything in the index.
+		 */
+		has_head = 0;
+ redo:
+	for (pos = 0; pos < active_nr; pos++) {
+		struct cache_entry *ce = active_cache[pos];
+		struct cache_entry *old = NULL;
+		int save_nr;
+
+		if (ce_stage(ce) || !ce_path_match(ce, pathspec))
+			continue;
+		if (has_head)
+			old = read_one_ent(NULL, head_sha1,
+					   ce->name, ce_namelen(ce), 0);
+		if (old && ce->ce_mode == old->ce_mode &&
+		    !memcmp(ce->sha1, old->sha1, 20)) {
+			free(old);
+			continue; /* unchanged */
+		}
+		/* Be careful.  The working tree may not have the
+		 * path anymore, in which case, under 'allow_remove',
+		 * or worse yet 'allow_replace', active_nr may decrease.
+		 */
+		save_nr = active_nr;
+		update_one(ce->name + prefix_length, prefix, prefix_length);
+		if (save_nr != active_nr)
+			goto redo;
+	}
+	return 0;
+}
 
 int main(int argc, const char **argv)
 {
@@ -478,6 +652,7 @@ int main(int argc, const char **argv)
 	int read_from_stdin = 0;
 	const char *prefix = setup_git_directory();
 	int prefix_length = prefix ? strlen(prefix) : 0;
+	char set_executable_bit = 0;
 
 	git_config(git_default_config);
 
@@ -544,8 +719,7 @@ int main(int argc, const char **argv)
 			    !strcmp(path, "--chmod=+x")) {
 				if (argc <= i+1)
 					die("git-update-index: %s <path>", path);
-				if (chmod_path(path[8], argv[++i]))
-					die("git-update-index: %s cannot chmod %s", path, argv[i]);
+				set_executable_bit = path[8];
 				continue;
 			}
 			if (!strcmp(path, "--assume-unchanged")) {
@@ -581,6 +755,20 @@ int main(int argc, const char **argv)
 				read_index_info(line_termination);
 				break;
 			}
+			if (!strcmp(path, "--unresolve")) {
+				has_errors = do_unresolve(argc - i, argv + i,
+							  prefix, prefix_length);
+				if (has_errors)
+					active_cache_changed = 0;
+				goto finish;
+			}
+			if (!strcmp(path, "--again")) {
+				has_errors = do_reupdate(argc - i, argv + i,
+							 prefix, prefix_length);
+				if (has_errors)
+					active_cache_changed = 0;
+				goto finish;
+			}
 			if (!strcmp(path, "--ignore-missing")) {
 				not_new = 1;
 				continue;
@@ -594,12 +782,15 @@ int main(int argc, const char **argv)
 			die("unknown option %s", path);
 		}
 		update_one(path, prefix, prefix_length);
+		if (set_executable_bit)
+			chmod_path(set_executable_bit, path);
 	}
 	if (read_from_stdin) {
 		struct strbuf buf;
 		strbuf_init(&buf);
 		while (1) {
 			char *path_name;
+			const char *p;
 			read_line(&buf, stdin, line_termination);
 			if (buf.eof)
 				break;
@@ -607,11 +798,18 @@ int main(int argc, const char **argv)
 				path_name = unquote_c_style(buf.buf, NULL);
 			else
 				path_name = buf.buf;
-			update_one(path_name, prefix, prefix_length);
+			p = prefix_path(prefix, prefix_length, path_name);
+			update_one(p, NULL, 0);
+			if (set_executable_bit)
+				chmod_path(set_executable_bit, p);
+			if (p < path_name || p > path_name + strlen(path_name))
+				free((char*) p);
 			if (path_name != buf.buf)
 				free(path_name);
 		}
 	}
+
+ finish:
 	if (active_cache_changed) {
 		if (write_cache(newfd, active_cache, active_nr) ||
 		    commit_index_file(&cache_file))