minor fixes for Windows

[openssl.git] / crypto / threads_win.c

diff --git a/crypto/threads_win.c b/crypto/threads_win.c
index ff4aae4f32fdf2d2729aee850a55909556f851f0..d8fdfb74f5b7b093ed3b926eb005c10c4f3df681 100644 (file)
--- a/crypto/threads_win.c
+++ b/crypto/threads_win.c
@@ -1,5 +1,5 @@
 /*
- * Copyright 2016 The OpenSSL Project Authors. All Rights Reserved.
+ * Copyright 2016-2018 The OpenSSL Project Authors. All Rights Reserved.
  *
  * Licensed under the OpenSSL license (the "License").  You may not use
  * this file except in compliance with the License.  You can obtain a copy
@@ -7,15 +7,22 @@
  * https://www.openssl.org/source/license.html
  */
 
+#if defined(_WIN32)
+# include <windows.h>
+#endif
+
 #include <openssl/crypto.h>
 
 #if defined(OPENSSL_THREADS) && !defined(CRYPTO_TDEBUG) && defined(OPENSSL_SYS_WINDOWS)
 
 CRYPTO_RWLOCK *CRYPTO_THREAD_lock_new(void)
 {
-    CRYPTO_RWLOCK *lock = OPENSSL_zalloc(sizeof(CRITICAL_SECTION));
-    if (lock == NULL)
+    CRYPTO_RWLOCK *lock;
+
+    if ((lock = OPENSSL_zalloc(sizeof(CRITICAL_SECTION))) == NULL) {
+        /* Don't set error, to avoid recursion blowup. */
         return NULL;
+    }
 
     /* 0x400 is the spin count value suggested in the documentation */
     if (!InitializeCriticalSectionAndSpinCount(lock, 0x400)) {
@@ -55,12 +62,14 @@ void CRYPTO_THREAD_lock_free(CRYPTO_RWLOCK *lock)
     return;
 }
 
-# if _WIN32_WINNT < 0x0600
-
 #  define ONCE_UNINITED     0
 #  define ONCE_ININIT       1
 #  define ONCE_DONE         2
 
+/*
+ * We don't use InitOnceExecuteOnce because that isn't available in WinXP which
+ * we still have to support.
+ */
 int CRYPTO_THREAD_run_once(CRYPTO_ONCE *once, void (*init)(void))
 {
     LONG volatile *lock = (LONG *)once;
@@ -81,27 +90,6 @@ int CRYPTO_THREAD_run_once(CRYPTO_ONCE *once, void (*init)(void))
     return (*lock == ONCE_DONE);
 }
 
-# else
-
-BOOL CALLBACK once_cb(PINIT_ONCE once, PVOID p, PVOID *pp)
-{
-    void (*init)(void) = p;
-
-    init();
-
-    return TRUE;
-}
-
-int CRYPTO_THREAD_run_once(CRYPTO_ONCE *once, void (*init)(void))
-{
-    if (InitOnceExecuteOnce(once, once_cb, init, NULL))
-        return 1;
-
-    return 0;
-}
-
-# endif
-
 int CRYPTO_THREAD_init_local(CRYPTO_THREAD_LOCAL *key, void (*cleanup)(void *))
 {
     *key = TlsAlloc();
@@ -113,7 +101,26 @@ int CRYPTO_THREAD_init_local(CRYPTO_THREAD_LOCAL *key, void (*cleanup)(void *))
 
 void *CRYPTO_THREAD_get_local(CRYPTO_THREAD_LOCAL *key)
 {
-    return TlsGetValue(*key);
+    DWORD last_error;
+    void *ret;
+
+    /*
+     * TlsGetValue clears the last error even on success, so that callers may
+     * distinguish it successfully returning NULL or failing. It is documented
+     * to never fail if the argument is a valid index from TlsAlloc, so we do
+     * not need to handle this.
+     *
+     * However, this error-mangling behavior interferes with the caller's use of
+     * GetLastError. In particular SSL_get_error queries the error queue to
+     * determine whether the caller should look at the OS's errors. To avoid
+     * destroying state, save and restore the Windows error.
+     *
+     * https://msdn.microsoft.com/en-us/library/windows/desktop/ms686812(v=vs.85).aspx
+     */
+    last_error = GetLastError();
+    ret = TlsGetValue(*key);
+    SetLastError(last_error);
+    return ret;
 }
 
 int CRYPTO_THREAD_set_local(CRYPTO_THREAD_LOCAL *key, void *val)
@@ -148,4 +155,9 @@ int CRYPTO_atomic_add(int *val, int amount, int *ret, CRYPTO_RWLOCK *lock)
     return 1;
 }
 
+int openssl_init_fork_handlers(void)
+{
+    return 0;
+}
+
 #endif