[runtime] Ensure mono-rand is opened once and only once

diff --git a/mono/utils/mono-rand.c b/mono/utils/mono-rand.c
index e8d193357592867831ae6602c8537f814aec04b8..71be40b92bf7fc5abc22553512baf33f3c7c835a 100644 (file)
--- a/mono/utils/mono-rand.c
+++ b/mono/utils/mono-rand.c
@@ -16,7 +16,9 @@
 #include <glib.h>
 #include <config.h>
 
+#include "atomic.h"
 #include "mono-rand.h"
+#include "mono-threads.h"
 #include "metadata/exception.h"
 #include "metadata/object.h"
 
@@ -188,8 +190,12 @@ get_entropy_from_egd (const char *path, guchar *buffer, int buffer_size)
 gboolean
 mono_rand_open (void)
 {
-       if (use_egd || (file >= 0))
+       static gint32 status = 0;
+       if (status != 0 || InterlockedCompareExchange (&status, 1, 0) != 0) {
+               while (status != 2)
+                       mono_thread_info_yield ();
                return TRUE;
+       }
 
 #ifdef NAME_DEV_URANDOM
        file = open (NAME_DEV_URANDOM, O_RDONLY);
@@ -201,6 +207,8 @@ mono_rand_open (void)
        if (file < 0)
                use_egd = g_getenv("MONO_EGD_SOCKET") != NULL;
 
+       status = 2;
+
        return TRUE;
 }
 
@@ -257,7 +265,17 @@ mono_rand_close (gpointer provider)
 gboolean
 mono_rand_open (void)
 {
+       static gint32 status = 0;
+       if (status != 0 || InterlockedCompareExchange (&status, 1, 0) != 0) {
+               while (status != 2)
+                       mono_thread_info_yield ();
+               return TRUE;
+       }
+
        srand (time (NULL));
+
+       status = 2;
+
        return TRUE;
 }