4 files changed, 121 insertions, 68 deletions
diff --git a/diff.c b/diff.c
index 5c428e02b6..48f719fb07 100644
--- a/diff.c
+++ b/diff.c
@@ -561,6 +561,13 @@ static void emit_line(struct diff_options *o, const char *set, const char *reset
 }
 
 enum diff_symbol {
+	DIFF_SYMBOL_SUBMODULE_ADD,
+	DIFF_SYMBOL_SUBMODULE_DEL,
+	DIFF_SYMBOL_SUBMODULE_UNTRACKED,
+	DIFF_SYMBOL_SUBMODULE_MODIFIED,
+	DIFF_SYMBOL_SUBMODULE_HEADER,
+	DIFF_SYMBOL_SUBMODULE_ERROR,
+	DIFF_SYMBOL_SUBMODULE_PIPETHROUGH,
 	DIFF_SYMBOL_REWRITE_DIFF,
 	DIFF_SYMBOL_BINARY_FILES,
 	DIFF_SYMBOL_HEADER,
@@ -625,6 +632,9 @@ static void emit_diff_symbol(struct diff_options *o, enum diff_symbol s,
 		emit_line_0(o, context, reset, '\\',
 			    nneof, strlen(nneof));
 		break;
+	case DIFF_SYMBOL_SUBMODULE_HEADER:
+	case DIFF_SYMBOL_SUBMODULE_ERROR:
+	case DIFF_SYMBOL_SUBMODULE_PIPETHROUGH:
 	case DIFF_SYMBOL_CONTEXT_FRAGINFO:
 		emit_line(o, "", "", line, len);
 		break;
@@ -701,11 +711,68 @@ static void emit_diff_symbol(struct diff_options *o, enum diff_symbol s,
 		reset = diff_get_color_opt(o, DIFF_RESET);
 		emit_line(o, fraginfo, reset, line, len);
 		break;
+	case DIFF_SYMBOL_SUBMODULE_ADD:
+		set = diff_get_color_opt(o, DIFF_FILE_NEW);
+		reset = diff_get_color_opt(o, DIFF_RESET);
+		emit_line(o, set, reset, line, len);
+		break;
+	case DIFF_SYMBOL_SUBMODULE_DEL:
+		set = diff_get_color_opt(o, DIFF_FILE_OLD);
+		reset = diff_get_color_opt(o, DIFF_RESET);
+		emit_line(o, set, reset, line, len);
+		break;
+	case DIFF_SYMBOL_SUBMODULE_UNTRACKED:
+		fprintf(o->file, "%sSubmodule %s contains untracked content\n",
+			diff_line_prefix(o), line);
+		break;
+	case DIFF_SYMBOL_SUBMODULE_MODIFIED:
+		fprintf(o->file, "%sSubmodule %s contains modified content\n",
+			diff_line_prefix(o), line);
+		break;
 	default:
 		die("BUG: unknown diff symbol");
 	}
 }
 
+void diff_emit_submodule_del(struct diff_options *o, const char *line)
+{
+	emit_diff_symbol(o, DIFF_SYMBOL_SUBMODULE_DEL, line, strlen(line), 0);
+}
+
+void diff_emit_submodule_add(struct diff_options *o, const char *line)
+{
+	emit_diff_symbol(o, DIFF_SYMBOL_SUBMODULE_ADD, line, strlen(line), 0);
+}
+
+void diff_emit_submodule_untracked(struct diff_options *o, const char *path)
+{
+	emit_diff_symbol(o, DIFF_SYMBOL_SUBMODULE_UNTRACKED,
+			 path, strlen(path), 0);
+}
+
+void diff_emit_submodule_modified(struct diff_options *o, const char *path)
+{
+	emit_diff_symbol(o, DIFF_SYMBOL_SUBMODULE_MODIFIED,
+			 path, strlen(path), 0);
+}
+
+void diff_emit_submodule_header(struct diff_options *o, const char *header)
+{
+	emit_diff_symbol(o, DIFF_SYMBOL_SUBMODULE_HEADER,
+			 header, strlen(header), 0);
+}
+
+void diff_emit_submodule_error(struct diff_options *o, const char *err)
+{
+	emit_diff_symbol(o, DIFF_SYMBOL_SUBMODULE_ERROR, err, strlen(err), 0);
+}
+
+void diff_emit_submodule_pipethrough(struct diff_options *o,
+				     const char *line, int len)
+{
+	emit_diff_symbol(o, DIFF_SYMBOL_SUBMODULE_PIPETHROUGH, line, len, 0);
+}
+
 static int new_blank_line_at_eof(struct emit_callback *ecbdata, const char *line, int len)
 {
 	if (!((ecbdata->ws_rule & WS_BLANK_AT_EOF) &&
@@ -2467,24 +2534,16 @@ static void builtin_diff(const char *name_a,
 	if (o->submodule_format == DIFF_SUBMODULE_LOG &&
 	    (!one->mode || S_ISGITLINK(one->mode)) &&
 	    (!two->mode || S_ISGITLINK(two->mode))) {
-		const char *del = diff_get_color_opt(o, DIFF_FILE_OLD);
-		const char *add = diff_get_color_opt(o, DIFF_FILE_NEW);
-		show_submodule_summary(o->file, one->path ? one->path : two->path,
-				line_prefix,
+		show_submodule_summary(o, one->path ? one->path : two->path,
 				&one->oid, &two->oid,
-				two->dirty_submodule,
-				meta, del, add, reset);
+				two->dirty_submodule);
 		return;
 	} else if (o->submodule_format == DIFF_SUBMODULE_INLINE_DIFF &&
 		   (!one->mode || S_ISGITLINK(one->mode)) &&
 		   (!two->mode || S_ISGITLINK(two->mode))) {
-		const char *del = diff_get_color_opt(o, DIFF_FILE_OLD);
-		const char *add = diff_get_color_opt(o, DIFF_FILE_NEW);
-		show_submodule_inline_diff(o->file, one->path ? one->path : two->path,
-				line_prefix,
+		show_submodule_inline_diff(o, one->path ? one->path : two->path,
 				&one->oid, &two->oid,
-				two->dirty_submodule,
-				meta, del, add, reset, o);
+				two->dirty_submodule);
 		return;
 	}
 
diff --git a/diff.h b/diff.h
index ea66168454..ae40bac7a9 100644
--- a/diff.h
+++ b/diff.h
@@ -188,6 +188,15 @@ struct diff_options {
 	int diff_path_counter;
 };
 
+void diff_emit_submodule_del(struct diff_options *o, const char *line);
+void diff_emit_submodule_add(struct diff_options *o, const char *line);
+void diff_emit_submodule_untracked(struct diff_options *o, const char *path);
+void diff_emit_submodule_modified(struct diff_options *o, const char *path);
+void diff_emit_submodule_header(struct diff_options *o, const char *header);
+void diff_emit_submodule_error(struct diff_options *o, const char *err);
+void diff_emit_submodule_pipethrough(struct diff_options *o,
+				     const char *line, int len);
+
 enum color_diff {
 	DIFF_RESET = 0,
 	DIFF_CONTEXT = 1,
diff --git a/submodule.c b/submodule.c
index da0b805493..07a3183150 100644
--- a/submodule.c
+++ b/submodule.c
@@ -479,9 +479,7 @@ static int prepare_submodule_summary(struct rev_info *rev, const char *path,
 	return prepare_revision_walk(rev);
 }
 
-static void print_submodule_summary(struct rev_info *rev, FILE *f,
-		const char *line_prefix,
-		const char *del, const char *add, const char *reset)
+static void print_submodule_summary(struct rev_info *rev, struct diff_options *o)
 {
 	static const char format[] = "  %m %s";
 	struct strbuf sb = STRBUF_INIT;
@@ -492,18 +490,12 @@ static void print_submodule_summary(struct rev_info *rev, FILE *f,
 		ctx.date_mode = rev->date_mode;
 		ctx.output_encoding = get_log_output_encoding();
 		strbuf_setlen(&sb, 0);
-		strbuf_addstr(&sb, line_prefix);
-		if (commit->object.flags & SYMMETRIC_LEFT) {
-			if (del)
-				strbuf_addstr(&sb, del);
-		}
-		else if (add)
-			strbuf_addstr(&sb, add);
 		format_commit_message(commit, format, &sb, &ctx);
-		if (reset)
-			strbuf_addstr(&sb, reset);
 		strbuf_addch(&sb, '\n');
-		fprintf(f, "%s", sb.buf);
+		if (commit->object.flags & SYMMETRIC_LEFT)
+			diff_emit_submodule_del(o, sb.buf);
+		else
+			diff_emit_submodule_add(o, sb.buf);
 	}
 	strbuf_release(&sb);
 }
@@ -530,11 +522,9 @@ void prepare_submodule_repo_env(struct argv_array *out)
  * attempt to lookup both the left and right commits and put them into the
  * left and right pointers.
  */
-static void show_submodule_header(FILE *f, const char *path,
-		const char *line_prefix,
+static void show_submodule_header(struct diff_options *o, const char *path,
 		struct object_id *one, struct object_id *two,
-		unsigned dirty_submodule, const char *meta,
-		const char *reset,
+		unsigned dirty_submodule,
 		struct commit **left, struct commit **right,
 		struct commit_list **merge_bases)
 {
@@ -543,11 +533,10 @@ static void show_submodule_header(FILE *f, const char *path,
 	int fast_forward = 0, fast_backward = 0;
 
 	if (dirty_submodule & DIRTY_SUBMODULE_UNTRACKED)
-		fprintf(f, "%sSubmodule %s contains untracked content\n",
-			line_prefix, path);
+		diff_emit_submodule_untracked(o, path);
+
 	if (dirty_submodule & DIRTY_SUBMODULE_MODIFIED)
-		fprintf(f, "%sSubmodule %s contains modified content\n",
-			line_prefix, path);
+		diff_emit_submodule_modified(o, path);
 
 	if (is_null_oid(one))
 		message = "(new submodule)";
@@ -589,31 +578,29 @@ static void show_submodule_header(FILE *f, const char *path,
 	}
 
 output_header:
-	strbuf_addf(&sb, "%s%sSubmodule %s ", line_prefix, meta, path);
+	strbuf_addf(&sb, "Submodule %s ", path);
 	strbuf_add_unique_abbrev(&sb, one->hash, DEFAULT_ABBREV);
 	strbuf_addstr(&sb, (fast_backward || fast_forward) ? ".." : "...");
 	strbuf_add_unique_abbrev(&sb, two->hash, DEFAULT_ABBREV);
 	if (message)
-		strbuf_addf(&sb, " %s%s\n", message, reset);
+		strbuf_addf(&sb, " %s\n", message);
 	else
-		strbuf_addf(&sb, "%s:%s\n", fast_backward ? " (rewind)" : "", reset);
-	fwrite(sb.buf, sb.len, 1, f);
+		strbuf_addf(&sb, "%s:\n", fast_backward ? " (rewind)" : "");
+	diff_emit_submodule_header(o, sb.buf);
 
 	strbuf_release(&sb);
 }
 
-void show_submodule_summary(FILE *f, const char *path,
-		const char *line_prefix,
+void show_submodule_summary(struct diff_options *o, const char *path,
 		struct object_id *one, struct object_id *two,
-		unsigned dirty_submodule, const char *meta,
-		const char *del, const char *add, const char *reset)
+		unsigned dirty_submodule)
 {
 	struct rev_info rev;
 	struct commit *left = NULL, *right = NULL;
 	struct commit_list *merge_bases = NULL;
 
-	show_submodule_header(f, path, line_prefix, one, two, dirty_submodule,
-			      meta, reset, &left, &right, &merge_bases);
+	show_submodule_header(o, path, one, two, dirty_submodule,
+			      &left, &right, &merge_bases);
 
 	/*
 	 * If we don't have both a left and a right pointer, there is no
@@ -625,11 +612,11 @@ void show_submodule_summary(FILE *f, const char *path,
 
 	/* Treat revision walker failure the same as missing commits */
 	if (prepare_submodule_summary(&rev, path, left, right, merge_bases)) {
-		fprintf(f, "%s(revision walker failed)\n", line_prefix);
+		diff_emit_submodule_error(o, "(revision walker failed)\n");
 		goto out;
 	}
 
-	print_submodule_summary(&rev, f, line_prefix, del, add, reset);
+	print_submodule_summary(&rev, o);
 
 out:
 	if (merge_bases)
@@ -638,21 +625,18 @@ out:
 	clear_commit_marks(right, ~0);
 }
 
-void show_submodule_inline_diff(FILE *f, const char *path,
-		const char *line_prefix,
+void show_submodule_inline_diff(struct diff_options *o, const char *path,
 		struct object_id *one, struct object_id *two,
-		unsigned dirty_submodule, const char *meta,
-		const char *del, const char *add, const char *reset,
-		const struct diff_options *o)
+		unsigned dirty_submodule)
 {
 	const struct object_id *old = &empty_tree_oid, *new = &empty_tree_oid;
 	struct commit *left = NULL, *right = NULL;
 	struct commit_list *merge_bases = NULL;
-	struct strbuf submodule_dir = STRBUF_INIT;
 	struct child_process cp = CHILD_PROCESS_INIT;
+	struct strbuf sb = STRBUF_INIT;
 
-	show_submodule_header(f, path, line_prefix, one, two, dirty_submodule,
-			      meta, reset, &left, &right, &merge_bases);
+	show_submodule_header(o, path, one, two, dirty_submodule,
+			      &left, &right, &merge_bases);
 
 	/* We need a valid left and right commit to display a difference */
 	if (!(left || is_null_oid(one)) ||
@@ -664,16 +648,16 @@ void show_submodule_inline_diff(FILE *f, const char *path,
 	if (right)
 		new = two;
 
-	fflush(f);
 	cp.git_cmd = 1;
 	cp.dir = path;
-	cp.out = dup(fileno(f));
+	cp.out = -1;
 	cp.no_stdin = 1;
 
 	/* TODO: other options may need to be passed here. */
 	argv_array_pushl(&cp.args, "diff", "--submodule=diff", NULL);
+	argv_array_pushf(&cp.args, "--color=%s", want_color(o->use_color) ?
+			 "always" : "never");
 
-	argv_array_pushf(&cp.args, "--line-prefix=%s", line_prefix);
 	if (DIFF_OPT_TST(o, REVERSE_DIFF)) {
 		argv_array_pushf(&cp.args, "--src-prefix=%s%s/",
 				 o->b_prefix, path);
@@ -696,11 +680,17 @@ void show_submodule_inline_diff(FILE *f, const char *path,
 		argv_array_push(&cp.args, oid_to_hex(new));
 
 	prepare_submodule_repo_env(&cp.env_array);
-	if (run_command(&cp))
-		fprintf(f, "(diff failed)\n");
+	if (start_command(&cp))
+		diff_emit_submodule_error(o, "(diff failed)\n");
+
+	while (strbuf_getwholeline_fd(&sb, cp.out, '\n') != EOF)
+		diff_emit_submodule_pipethrough(o, sb.buf, sb.len);
+
+	if (finish_command(&cp))
+		diff_emit_submodule_error(o, "(diff failed)\n");
 
 done:
-	strbuf_release(&submodule_dir);
+	strbuf_release(&sb);
 	if (merge_bases)
 		free_commit_list(merge_bases);
 	if (left)
diff --git a/submodule.h b/submodule.h
index cbe5c1726f..829d975585 100644
--- a/submodule.h
+++ b/submodule.h
@@ -63,17 +63,12 @@ extern int parse_submodule_update_strategy(const char *value,
 		struct submodule_update_strategy *dst);
 extern const char *submodule_strategy_to_string(const struct submodule_update_strategy *s);
 extern void handle_ignore_submodules_arg(struct diff_options *, const char *);
-extern void show_submodule_summary(FILE *f, const char *path,
-		const char *line_prefix,
+extern void show_submodule_summary(struct diff_options *o, const char *path,
 		struct object_id *one, struct object_id *two,
-		unsigned dirty_submodule, const char *meta,
-		const char *del, const char *add, const char *reset);
-extern void show_submodule_inline_diff(FILE *f, const char *path,
-		const char *line_prefix,
+		unsigned dirty_submodule);
+extern void show_submodule_inline_diff(struct diff_options *o, const char *path,
 		struct object_id *one, struct object_id *two,
-		unsigned dirty_submodule, const char *meta,
-		const char *del, const char *add, const char *reset,
-		const struct diff_options *opt);
+		unsigned dirty_submodule);
 extern void set_config_fetch_recurse_submodules(int value);
 /* Check if we want to update any submodule.*/
 extern int should_update_submodules(void);