1/*
2 * Copyright (C) 2016 Apple Inc. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR
17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#pragma once
27
28#include <wtf/PrintStream.h>
29#include <wtf/RecursiveLockAdapter.h>
30#include <wtf/WordLock.h>
31
32namespace WTF {
33
34// Makes every call to print() atomic.
35class LockedPrintStream : public PrintStream {
36public:
37 LockedPrintStream(std::unique_ptr<PrintStream> target);
38 virtual ~LockedPrintStream();
39
40 void vprintf(const char* format, va_list) override WTF_ATTRIBUTE_PRINTF(2, 0);
41 void flush() override;
42
43protected:
44 PrintStream& begin() override;
45 void end() override;
46
47private:
48 // This needs to be a recursive lock because a printInternal or dump method could assert,
49 // and that assert might want to log. Better to let it. This needs to be a WordLock so that
50 // LockedPrintStream (i.e. cataLog) can be used to debug ParkingLot and Lock.
51 RecursiveLockAdapter<WordLock> m_lock;
52 std::unique_ptr<PrintStream> m_target;
53};
54
55} // namespace WTF
56
57using WTF::LockedPrintStream;
58
59