merge: teach -Xours/-Xtheirs to binary ll-merge driver

The (discouraged) -Xours/-Xtheirs modes of merge are supposed to
give a quick and dirty way to come up with a random mixture of
cleanly merged parts and punted conflict resolution to take contents
from one side in conflicting parts.  These options however were only
passed down to the low level merge driver for text.

Teach the built-in binary merge driver to notice them as well.

Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 20 insertions, 5 deletions

diff --git a/ll-merge.c b/ll-merge.c
index da59738c9..8535e2d4a 100644
--- a/ll-merge.c
+++ b/ll-merge.c
@@ -46,16 +46,31 @@ static int ll_binary_merge(const struct ll_merge_driver *drv_unused,
 	assert(opts);
 
 	/*
-	 * The tentative merge result is "ours" for the final round,
-	 * or common ancestor for an internal merge.  Still return
-	 * "conflicted merge" status.
+	 * The tentative merge result is the or common ancestor for an internal merge.
 	 */
-	stolen = opts->virtual_ancestor ? orig : src1;
+	if (opts->virtual_ancestor) {
+		stolen = orig;
+	} else {
+		switch (opts->variant) {
+		default:
+		case XDL_MERGE_FAVOR_OURS:
+			stolen = src1;
+			break;
+		case XDL_MERGE_FAVOR_THEIRS:
+			stolen = src2;
+			break;
+		}
+	}
 
 	result->ptr = stolen->ptr;
 	result->size = stolen->size;
 	stolen->ptr = NULL;
-	return 1;
+
+	/*
+	 * With -Xtheirs or -Xours, we have cleanly merged;
+	 * otherwise we got a conflict.
+	 */
+	return (opts->variant ? 0 : 1);
 }
 
 static int ll_xdl_merge(const struct ll_merge_driver *drv_unused,