/*

 * Copyright 2016-2020 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

 * in the file LICENSE in the source distribution or at

 * 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;

    if ((lock = OPENSSL_zalloc(sizeof(CRITICAL_SECTION))) == NULL) {

        /* Don't set error, to avoid recursion blowup. */

        return NULL;

    }

# if !defined(_WIN32_WCE)

    /* 0x400 is the spin count value suggested in the documentation */

    if (!InitializeCriticalSectionAndSpinCount(lock, 0x400)) {

        OPENSSL_free(lock);

        return NULL;

    }

# else

    InitializeCriticalSection(lock);

# endif

    return lock;

}

int CRYPTO_THREAD_read_lock(CRYPTO_RWLOCK *lock)

{

    EnterCriticalSection(lock);

    return 1;

}

int CRYPTO_THREAD_write_lock(CRYPTO_RWLOCK *lock)

{

    EnterCriticalSection(lock);

    return 1;

}

int CRYPTO_THREAD_unlock(CRYPTO_RWLOCK *lock)

{

    LeaveCriticalSection(lock);

    return 1;

}

void CRYPTO_THREAD_lock_free(CRYPTO_RWLOCK *lock)

{

    if (lock == NULL)

        return;

    DeleteCriticalSection(lock);

    OPENSSL_free(lock);

    return;

}

#  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;

    LONG result;

    if (*lock == ONCE_DONE)

        return 1;

    do {

        result = InterlockedCompareExchange(lock, ONCE_ININIT, ONCE_UNINITED);

        if (result == ONCE_UNINITED) {

            init();

            *lock = ONCE_DONE;

            return 1;

        }

    } while (result == ONCE_ININIT);

    return (*lock == ONCE_DONE);

}

int CRYPTO_THREAD_init_local(CRYPTO_THREAD_LOCAL *key, void (*cleanup)(void *))

{

    *key = TlsAlloc();

    if (*key == TLS_OUT_OF_INDEXES)

        return 0;

    return 1;

}

void *CRYPTO_THREAD_get_local(CRYPTO_THREAD_LOCAL *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)

{

    if (TlsSetValue(*key, val) == 0)

        return 0;

    return 1;

}

int CRYPTO_THREAD_cleanup_local(CRYPTO_THREAD_LOCAL *key)

{

    if (TlsFree(*key) == 0)

        return 0;

    return 1;

}

CRYPTO_THREAD_ID CRYPTO_THREAD_get_current_id(void)

{

    return GetCurrentThreadId();

}

int CRYPTO_THREAD_compare_id(CRYPTO_THREAD_ID a, CRYPTO_THREAD_ID b)

{

    return (a == b);

}

int CRYPTO_atomic_add(int *val, int amount, int *ret, CRYPTO_RWLOCK *lock)

{

    *ret = (int)InterlockedExchangeAdd((long volatile *)val, (long)amount) + amount;

    return 1;

}

int openssl_init_fork_handlers(void)

{

    return 0;

}

int openssl_get_fork_id(void)

{

    return 0;

}

#endif