From e0737b5ca3d2de56947a5e33f50c54b1277e533b Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Tue, 6 Oct 2009 14:09:26 +0200
Subject: [PATCH] WIP: do --submodule-summary using child_processes

This is super-ugly, and will suck on Windows, but Junio does not trust
my words.

This is _not_ meant for application, but just for quick-n-dirty testing.
For one, it loses coloring, and two, it loses correct determination
of fast-forwards vs non-fast-forwards, and three, it does not make the
SHA-1s being correctly abbreviated.

BUT.  I have no inclination of wasting my time even more, even if
Junio asks for it.  It really sucks that I have to do this.
---
 submodule.c | 92 ++++++++++++++++++++-----------------------------------------
 1 file changed, 30 insertions(+), 62 deletions(-)

diff --git a/submodule.c b/submodule.c
index b441ea1fc4..4e5c1c54cd 100644
--- a/submodule.c
+++ b/submodule.c
@@ -1,9 +1,6 @@
 #include "cache.h"
 #include "submodule.h"
-#include "dir.h"
-#include "diff.h"
-#include "commit.h"
-#include "revision.h"
+#include "run-command.h"
 
 int add_submodule_odb(const char *path)
 {
@@ -37,13 +34,8 @@ void show_submodule_summary(FILE *f, const char *path,
 		unsigned char one[20], unsigned char two[20],
 		const char *del, const char *add, const char *reset)
 {
-	struct rev_info rev;
-	struct commit *commit, *left, *right;
-	struct commit_list *merge_bases, *list;
-	const char *message = NULL;
 	struct strbuf sb = STRBUF_INIT;
-	static const char *format = "    %m %s";
-	int fast_forward = 0, fast_backward = 0;
+	const char *message = NULL;
 
 	if (add_submodule_odb(path))
 		message = "(not checked out)";
@@ -51,61 +43,37 @@ void show_submodule_summary(FILE *f, const char *path,
 		message = "(new submodule)";
 	else if (is_null_sha1(two))
 		message = "(submodule deleted)";
-	else if (!(left = lookup_commit_reference(one)) ||
-			!(right = lookup_commit_reference(two)))
-		message = "(commits not present)";
 
 	if (!message) {
-		init_revisions(&rev, NULL);
-		setup_revisions(0, NULL, &rev, NULL);
-		rev.left_right = 1;
-		left->object.flags |= SYMMETRIC_LEFT;
-		add_pending_object(&rev, &left->object, path);
-		add_pending_object(&rev, &right->object, path);
-		merge_bases = get_merge_bases(left, right, 1);
-		if (merge_bases) {
-			if (merge_bases->item == left)
-				fast_forward = 1;
-			else if (merge_bases->item == right)
-				fast_backward = 1;
-		}
-		for (list = merge_bases; list; list = list->next) {
-			list->item->object.flags |= UNINTERESTING;
-			add_pending_object(&rev, &list->item->object,
-				sha1_to_hex(list->item->object.sha1));
-		}
-		if (prepare_revision_walk(&rev))
-			message = "(revision walker failed)";
-	}
+		struct child_process child;
+		struct strbuf range = STRBUF_INIT;
+		const char* argv[] = {
+			"log", "--pretty=format:  %m %s", "--left-right",
+			NULL, "--", NULL
+		};
 
-	strbuf_addf(&sb, "Submodule %s %s..", path,
-			find_unique_abbrev(one, DEFAULT_ABBREV));
-	if (!fast_backward && !fast_forward)
-		strbuf_addch(&sb, '.');
-	strbuf_addf(&sb, "%s", find_unique_abbrev(two, DEFAULT_ABBREV));
-	if (message)
-		strbuf_addf(&sb, " %s\n", message);
-	else
-		strbuf_addf(&sb, "%s:\n", fast_backward ? " (rewind)" : "");
-	fwrite(sb.buf, sb.len, 1, f);
+		strbuf_addf(&range, "%s...%s",
+				sha1_to_hex(one), sha1_to_hex(two));
+		argv[3] = range.buf;
+		memset(&child, 0, sizeof(child));
+		child.argv = argv;
+		child.dir = path;
+		child.no_stdin = 1;
+		child.out = fileno(f);
+		child.err = fileno(stderr);
+		child.git_cmd = 1;
 
-	if (!message) {
-		while ((commit = get_revision(&rev))) {
-			strbuf_setlen(&sb, 0);
-			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,
-					rev.date_mode);
-			if (reset)
-				strbuf_addstr(&sb, reset);
-			strbuf_addch(&sb, '\n');
-			fprintf(f, "%s", sb.buf);
-		}
-		clear_commit_marks(left, ~0);
-		clear_commit_marks(right, ~0);
+		fprintf(f, "Submodule %s %s:\n", path, range.buf);
+		fflush(f);
+		run_command(&child);
+		strbuf_release(&range);
+		return;
 	}
+
+	strbuf_addf(&sb, "Submodule %s %s...%s %s\n", path,
+			find_unique_abbrev(one, DEFAULT_ABBREV),
+			find_unique_abbrev(two, DEFAULT_ABBREV),
+			message);
+	fprintf(f, "%s", sb.buf);
+	strbuf_release(&sb);
 }
-- 
2.11.4.GIT