Add memrandomize to fuzz/c/fuzzlib
diff --git a/fuzz/c/fuzzlib/fuzzlib.c b/fuzz/c/fuzzlib/fuzzlib.c
index 1fb1861..45178f7 100644
--- a/fuzz/c/fuzzlib/fuzzlib.c
+++ b/fuzz/c/fuzzlib/fuzzlib.c
@@ -44,6 +44,19 @@
return hash;
}
+// memrandomize is like memcpy or memset but it writes pseudo-random values.
+static void* //
+memrandomize(void* dest, uint64_t seed, size_t n) {
+ unsigned short xsubi[3]; // See "man 3 nrand48".
+ xsubi[0] = (seed >> 0) ^ (seed >> 48);
+ xsubi[1] = (seed >> 16);
+ xsubi[2] = (seed >> 32);
+ for (uint8_t* ptr = (uint8_t*)dest; n--;) {
+ *ptr++ = nrand48(xsubi);
+ }
+ return dest;
+}
+
const char* //
fuzz(wuffs_base__io_buffer* src, uint64_t hash);
