fix build on _WIN32

rand.c

@@ -22,7 +22,11 @@
  */
 
 #include <stdio.h>
+#ifdef _WIN32
+#include <time.h>
+#else
 #include <assert.h>
+#endif
 
 #include "rand.h"
 
@@ -30,14 +34,22 @@ static FILE *frand = NULL;
 
 int finalize_rand(void)
 {
+#ifdef _WIN32
+	return 0;
+#else
 	if (!frand) return 0;
 	int err = fclose(frand);
 	frand = NULL;
 	return err;
+#endif
 }
 
 uint32_t random32(void)
 {
+#ifdef _WIN32
+	srand((unsigned)time(NULL));
+	return ((rand() % 0xFF) | ((rand() % 0xFF) << 8) | ((rand() % 0xFF) << 16) | ((rand() % 0xFF) << 24));
+#else
 	uint32_t r;
 	size_t len = sizeof(r);
 	if (!frand) {
@@ -47,6 +59,7 @@ uint32_t random32(void)
 	(void)len_read;
 	assert(len_read == len);
 	return r;
+#endif
 }
 
 uint32_t random_uniform(uint32_t n)
@@ -58,12 +71,20 @@ uint32_t random_uniform(uint32_t n)
 
 void random_buffer(uint8_t *buf, size_t len)
 {
+#ifdef _WIN32
+	srand((unsigned)time(NULL));
+	size_t i;
+	for (i = 0; i < len; i++) {
+		buf[i] = rand() % 0xFF;
+	}
+#else
 	if (!frand) {
 		frand = fopen("/dev/urandom", "r");
 	}
 	size_t len_read = fread(buf, 1, len, frand);
 	(void)len_read;
 	assert(len_read == len);
+#endif
 }
 
 void random_permute(char *str, size_t len)