1 files changed, 51 insertions, 51 deletions
diff --git a/diff.c b/diff.c
index 285d6e2d57..9f9a92ec9d 100644
--- a/diff.c
+++ b/diff.c
@@ -4301,35 +4301,34 @@ static void run_external_diff(const char *pgm,
 			      const char *xfrm_msg,
 			      struct diff_options *o)
 {
-	struct strvec argv = STRVEC_INIT;
-	struct strvec env = STRVEC_INIT;
+	struct child_process cmd = CHILD_PROCESS_INIT;
 	struct diff_queue_struct *q = &diff_queued_diff;
 
-	strvec_push(&argv, pgm);
-	strvec_push(&argv, name);
+	strvec_push(&cmd.args, pgm);
+	strvec_push(&cmd.args, name);
 
 	if (one && two) {
-		add_external_diff_name(o->repo, &argv, name, one);
+		add_external_diff_name(o->repo, &cmd.args, name, one);
 		if (!other)
-			add_external_diff_name(o->repo, &argv, name, two);
+			add_external_diff_name(o->repo, &cmd.args, name, two);
 		else {
-			add_external_diff_name(o->repo, &argv, other, two);
-			strvec_push(&argv, other);
-			strvec_push(&argv, xfrm_msg);
+			add_external_diff_name(o->repo, &cmd.args, other, two);
+			strvec_push(&cmd.args, other);
+			strvec_push(&cmd.args, xfrm_msg);
 		}
 	}
 
-	strvec_pushf(&env, "GIT_DIFF_PATH_COUNTER=%d", ++o->diff_path_counter);
-	strvec_pushf(&env, "GIT_DIFF_PATH_TOTAL=%d", q->nr);
+	strvec_pushf(&cmd.env, "GIT_DIFF_PATH_COUNTER=%d",
+		     ++o->diff_path_counter);
+	strvec_pushf(&cmd.env, "GIT_DIFF_PATH_TOTAL=%d", q->nr);
 
 	diff_free_filespec_data(one);
 	diff_free_filespec_data(two);
-	if (run_command_v_opt_cd_env(argv.v, RUN_USING_SHELL, NULL, env.v))
+	cmd.use_shell = 1;
+	if (run_command(&cmd))
 		die(_("external diff died, stopping at %s"), name);
 
 	remove_tempfile();
-	strvec_clear(&argv);
-	strvec_clear(&env);
 }
 
 static int similarity_index(struct diff_filepair *p)
@@ -6229,7 +6228,7 @@ static void patch_id_add_mode(git_hash_ctx *ctx, unsigned mode)
 }
 
 /* returns 0 upon success, and writes result into oid */
-static int diff_get_patch_id(struct diff_options *options, struct object_id *oid, int diff_header_only, int stable)
+static int diff_get_patch_id(struct diff_options *options, struct object_id *oid, int diff_header_only)
 {
 	struct diff_queue_struct *q = &diff_queued_diff;
 	int i;
@@ -6276,61 +6275,62 @@ static int diff_get_patch_id(struct diff_options *options, struct object_id *oid
 		if (p->one->mode == 0) {
 			patch_id_add_string(&ctx, "newfilemode");
 			patch_id_add_mode(&ctx, p->two->mode);
-			patch_id_add_string(&ctx, "---/dev/null");
-			patch_id_add_string(&ctx, "+++b/");
-			the_hash_algo->update_fn(&ctx, p->two->path, len2);
 		} else if (p->two->mode == 0) {
 			patch_id_add_string(&ctx, "deletedfilemode");
 			patch_id_add_mode(&ctx, p->one->mode);
-			patch_id_add_string(&ctx, "---a/");
-			the_hash_algo->update_fn(&ctx, p->one->path, len1);
-			patch_id_add_string(&ctx, "+++/dev/null");
-		} else {
-			patch_id_add_string(&ctx, "---a/");
-			the_hash_algo->update_fn(&ctx, p->one->path, len1);
-			patch_id_add_string(&ctx, "+++b/");
-			the_hash_algo->update_fn(&ctx, p->two->path, len2);
+		} else if (p->one->mode != p->two->mode) {
+			patch_id_add_string(&ctx, "oldmode");
+			patch_id_add_mode(&ctx, p->one->mode);
+			patch_id_add_string(&ctx, "newmode");
+			patch_id_add_mode(&ctx, p->two->mode);
 		}
 
-		if (diff_header_only)
-			continue;
-
-		if (fill_mmfile(options->repo, &mf1, p->one) < 0 ||
-		    fill_mmfile(options->repo, &mf2, p->two) < 0)
-			return error("unable to read files to diff");
-
-		if (diff_filespec_is_binary(options->repo, p->one) ||
+		if (diff_header_only) {
+			/* don't do anything since we're only populating header info */
+		} else if (diff_filespec_is_binary(options->repo, p->one) ||
 		    diff_filespec_is_binary(options->repo, p->two)) {
 			the_hash_algo->update_fn(&ctx, oid_to_hex(&p->one->oid),
 					the_hash_algo->hexsz);
 			the_hash_algo->update_fn(&ctx, oid_to_hex(&p->two->oid),
 					the_hash_algo->hexsz);
-			continue;
-		}
-
-		xpp.flags = 0;
-		xecfg.ctxlen = 3;
-		xecfg.flags = XDL_EMIT_NO_HUNK_HDR;
-		if (xdi_diff_outf(&mf1, &mf2, NULL,
-				  patch_id_consume, &data, &xpp, &xecfg))
-			return error("unable to generate patch-id diff for %s",
-				     p->one->path);
+		} else {
+			if (p->one->mode == 0) {
+				patch_id_add_string(&ctx, "---/dev/null");
+				patch_id_add_string(&ctx, "+++b/");
+				the_hash_algo->update_fn(&ctx, p->two->path, len2);
+			} else if (p->two->mode == 0) {
+				patch_id_add_string(&ctx, "---a/");
+				the_hash_algo->update_fn(&ctx, p->one->path, len1);
+				patch_id_add_string(&ctx, "+++/dev/null");
+			} else {
+				patch_id_add_string(&ctx, "---a/");
+				the_hash_algo->update_fn(&ctx, p->one->path, len1);
+				patch_id_add_string(&ctx, "+++b/");
+				the_hash_algo->update_fn(&ctx, p->two->path, len2);
+			}
 
-		if (stable)
-			flush_one_hunk(oid, &ctx);
+			if (fill_mmfile(options->repo, &mf1, p->one) < 0 ||
+			    fill_mmfile(options->repo, &mf2, p->two) < 0)
+				return error("unable to read files to diff");
+			xpp.flags = 0;
+			xecfg.ctxlen = 3;
+			xecfg.flags = XDL_EMIT_NO_HUNK_HDR;
+			if (xdi_diff_outf(&mf1, &mf2, NULL,
+					  patch_id_consume, &data, &xpp, &xecfg))
+				return error("unable to generate patch-id diff for %s",
+					     p->one->path);
+		}
+		flush_one_hunk(oid, &ctx);
 	}
 
-	if (!stable)
-		the_hash_algo->final_oid_fn(oid, &ctx);
-
 	return 0;
 }
 
-int diff_flush_patch_id(struct diff_options *options, struct object_id *oid, int diff_header_only, int stable)
+int diff_flush_patch_id(struct diff_options *options, struct object_id *oid, int diff_header_only)
 {
 	struct diff_queue_struct *q = &diff_queued_diff;
 	int i;
-	int result = diff_get_patch_id(options, oid, diff_header_only, stable);
+	int result = diff_get_patch_id(options, oid, diff_header_only);
 
 	for (i = 0; i < q->nr; i++)
 		diff_free_filepair(q->queue[i]);