1 files changed, 78 insertions, 0 deletions
diff --git a/t/helper/test-delta.c b/t/helper/test-delta.c
new file mode 100644
index 0000000000..59937dc1be
--- /dev/null
+++ b/t/helper/test-delta.c
@@ -0,0 +1,78 @@
+/*
+ * test-delta.c: test code to exercise diff-delta.c and patch-delta.c
+ *
+ * (C) 2005 Nicolas Pitre <nico@fluxnic.net>
+ *
+ * This code is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include "git-compat-util.h"
+#include "delta.h"
+#include "cache.h"
+
+static const char usage_str[] =
+	"test-delta (-d|-p) <from_file> <data_file> <out_file>";
+
+int cmd_main(int argc, const char **argv)
+{
+	int fd;
+	struct stat st;
+	void *from_buf, *data_buf, *out_buf;
+	unsigned long from_size, data_size, out_size;
+
+	if (argc != 5 || (strcmp(argv[1], "-d") && strcmp(argv[1], "-p"))) {
+		fprintf(stderr, "usage: %s\n", usage_str);
+		return 1;
+	}
+
+	fd = open(argv[2], O_RDONLY);
+	if (fd < 0 || fstat(fd, &st)) {
+		perror(argv[2]);
+		return 1;
+	}
+	from_size = st.st_size;
+	from_buf = mmap(NULL, from_size, PROT_READ, MAP_PRIVATE, fd, 0);
+	if (from_buf == MAP_FAILED) {
+		perror(argv[2]);
+		close(fd);
+		return 1;
+	}
+	close(fd);
+
+	fd = open(argv[3], O_RDONLY);
+	if (fd < 0 || fstat(fd, &st)) {
+		perror(argv[3]);
+		return 1;
+	}
+	data_size = st.st_size;
+	data_buf = mmap(NULL, data_size, PROT_READ, MAP_PRIVATE, fd, 0);
+	if (data_buf == MAP_FAILED) {
+		perror(argv[3]);
+		close(fd);
+		return 1;
+	}
+	close(fd);
+
+	if (argv[1][1] == 'd')
+		out_buf = diff_delta(from_buf, from_size,
+				     data_buf, data_size,
+				     &out_size, 0);
+	else
+		out_buf = patch_delta(from_buf, from_size,
+				      data_buf, data_size,
+				      &out_size);
+	if (!out_buf) {
+		fprintf(stderr, "delta operation failed (returned NULL)\n");
+		return 1;
+	}
+
+	fd = open (argv[4], O_WRONLY|O_CREAT|O_TRUNC, 0666);
+	if (fd < 0 || write_in_full(fd, out_buf, out_size) != out_size) {
+		perror(argv[4]);
+		return 1;
+	}
+
+	return 0;
+}