1 files changed, 34 insertions, 0 deletions
diff --git a/t/helper/test-genrandom.c b/t/helper/test-genrandom.c
new file mode 100644
index 000000000000..99b8dc1e2d9c
--- /dev/null
+++ b/t/helper/test-genrandom.c
@@ -0,0 +1,34 @@
+/*
+ * Simple random data generator used to create reproducible test files.
+ * This is inspired from POSIX.1-2001 implementation example for rand().
+ * Copyright (C) 2007 by Nicolas Pitre, licensed under the GPL version 2.
+ */
+
+#include "test-tool.h"
+#include "git-compat-util.h"
+
+int cmd__genrandom(int argc, const char **argv)
+{
+	unsigned long count, next = 0;
+	unsigned char *c;
+
+	if (argc < 2 || argc > 3) {
+		fprintf(stderr, "usage: %s <seed_string> [<size>]\n", argv[0]);
+		return 1;
+	}
+
+	c = (unsigned char *) argv[1];
+	do {
+		next = next * 11 + *c;
+	} while (*c++);
+
+	count = (argc == 3) ? strtoul(argv[2], NULL, 0) : -1L;
+
+	while (count--) {
+		next = next * 1103515245 + 12345;
+		if (putchar((next >> 16) & 0xff) == EOF)
+			return -1;
+	}
+
+	return 0;
+}