diff options
-rw-r--r-- | evutil_rand.c | 16 |
1 files changed, 14 insertions, 2 deletions
diff --git a/evutil_rand.c b/evutil_rand.c index 3cc163d3..e2bf605f 100644 --- a/evutil_rand.c +++ b/evutil_rand.c @@ -58,10 +58,22 @@ evutil_secure_rng_global_setup_locks_(const int enable_locks) static void ev_arc4random_buf(void *buf, size_t n) { -#ifdef _EVENT_HAVE_ARC4RANDOM_BUF + unsigned char *b = buf; +#if defined(_EVENT_HAVE_ARC4RANDOM_BUF) && !defined(__APPLE__) return arc4random_buf(buf, n); #else - unsigned char *b = buf; + +#if defined(_EVENT_HAVE_ARC4RANDOM_BUF) + /* OSX 10.7 introducd arc4random_buf, so if you build your program + * there, you'll get surprised when older versions of OSX fail to run. + * To solve this, we can check whether the function pointer is set, + * and fall back otherwise. (OSX does this using some linker + * trickery.) + */ + if (arc4random_buf) { + return arc4random_buf(buf, n); + } +#endif /* Make sure that we start out with b at a 4-byte alignment; plenty * of CPUs care about this for 32-bit access. */ if (n >= 4 && ((ev_uintptr_t)b) & 3) { |