Fix ThreadCachedInt race condition

[folly.git] / folly / Random.cpp

diff --git a/folly/Random.cpp b/folly/Random.cpp
index dfe9270bf15517109f34a4436d5a09256c9ce2ec..8f5e3128d2036952f31ba8efcc73791a139e333b 100644 (file)
--- a/folly/Random.cpp
+++ b/folly/Random.cpp
@@ -17,16 +17,17 @@
 #include <folly/Random.h>
 
 #include <atomic>
-#include <unistd.h>
-#include <sys/time.h>
 #include <mutex>
 #include <random>
 #include <array>
 
 #include <glog/logging.h>
+#include <folly/CallOnce.h>
 #include <folly/File.h>
 #include <folly/FileUtil.h>
 #include <folly/ThreadLocal.h>
+#include <folly/portability/SysTime.h>
+#include <folly/portability/Unistd.h>
 
 #ifdef _MSC_VER
 # include <wincrypt.h>
@@ -38,11 +39,19 @@ namespace {
 
 void readRandomDevice(void* data, size_t size) {
 #ifdef _MSC_VER
-  static std::once_flag flag;
+  static folly::once_flag flag;
   static HCRYPTPROV cryptoProv;
-  std::call_once(flag, [&] {
-    PCHECK(CryptAcquireContext(&cryptoProv, nullptr, nullptr,
-                               PROV_RSA_FULL, 0));
+  folly::call_once(flag, [&] {
+    if (!CryptAcquireContext(&cryptoProv, nullptr, nullptr, PROV_RSA_FULL, 0)) {
+      if (GetLastError() == NTE_BAD_KEYSET) {
+        // Mostly likely cause of this is that no key container
+        // exists yet, so try to create one.
+        PCHECK(CryptAcquireContext(
+            &cryptoProv, nullptr, nullptr, PROV_RSA_FULL, CRYPT_NEWKEYSET));
+      } else {
+        LOG(FATAL) << "Failed to acquire the default crypto context.";
+      }
+    }
   });
   CHECK(size <= std::numeric_limits<DWORD>::max());
   PCHECK(CryptGenRandom(cryptoProv, (DWORD)size, (BYTE*)data));