Merge branch 'sb/diff-orderfile-config'

Allow "git diff -O<file>" to be configured with a new configuration
variable.

* sb/diff-orderfile-config:
  diff: add diff.orderfile configuration variable
  diff: let "git diff -O" read orderfile from any file and fail properly
  t4056: add new tests for "git diff -O"

1 files changed, 8 insertions, 15 deletions

diff --git a/diffcore-order.c b/diffcore-order.c
index 50c089bb2b..fe7f1f4647 100644
--- a/diffcore-order.c
+++ b/diffcore-order.c
@@ -10,28 +10,21 @@ static int order_cnt;
 
 static void prepare_order(const char *orderfile)
 {
-	int fd, cnt, pass;
+	int cnt, pass;
+	struct strbuf sb = STRBUF_INIT;
 	void *map;
 	char *cp, *endp;
-	struct stat st;
-	size_t sz;
+	ssize_t sz;
 
 	if (order)
 		return;
 
-	fd = open(orderfile, O_RDONLY);
-	if (fd < 0)
-		return;
-	if (fstat(fd, &st)) {
-		close(fd);
-		return;
-	}
-	sz = xsize_t(st.st_size);
-	map = mmap(NULL, sz, PROT_READ|PROT_WRITE, MAP_PRIVATE, fd, 0);
-	close(fd);
-	if (map == MAP_FAILED)
-		return;
+	sz = strbuf_read_file(&sb, orderfile, 0);
+	if (sz < 0)
+		die_errno(_("failed to read orderfile '%s'"), orderfile);
+	map = strbuf_detach(&sb, NULL);
 	endp = (char *) map + sz;
+
 	for (pass = 0; pass < 2; pass++) {
 		cnt = 0;
 		cp = map;