submodule.c: migrate diff output to use emit_diff_symbol

As the submodule process is no longer attached to the same file pointer
'o->file' as the superprojects process, there is a different result in
color.c::check_auto_color. That is why we need to pass coloring explicitly,
such that the submodule coloring decision will be made by the child process
processing the submodule. Only DIFF_SYMBOL_SUBMODULE_PIPETHROUGH contains
color, the other symbols are for embedding the submodule output into the
superprojects output.

Remove the colors from the function signatures, as all the coloring
decisions will be made either inside the child process or the final
emit_diff_symbol, but not in the functions driving the submodule diff.

Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 37 insertions, 47 deletions

diff --git a/submodule.c b/submodule.c
index da0b805..07a3183 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)