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-rw-r--r--t/helper/test-genrandom.c33
1 files changed, 33 insertions, 0 deletions
diff --git a/t/helper/test-genrandom.c b/t/helper/test-genrandom.c
new file mode 100644
index 0000000000..8d11d22d98
--- /dev/null
+++ b/t/helper/test-genrandom.c
@@ -0,0 +1,33 @@
+/*
+ * 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 "git-compat-util.h"
+
+int cmd_main(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;
+}