1 // Copyright (c) 2011 The LevelDB Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file. See the AUTHORS file for names of contributors.
4
5 #include "port/port_chromium.h"
6
7 #include "base/threading/platform_thread.h"
8 #include "util/logging.h"
9
10 #if defined(USE_SNAPPY)
11 # include "third_party/snappy/src/snappy.h"
12 #endif
13
14 namespace leveldb {
15 namespace port {
16
Mutex()17 Mutex::Mutex() {
18 }
19
~Mutex()20 Mutex::~Mutex() {
21 }
22
Lock()23 void Mutex::Lock() {
24 mu_.Acquire();
25 }
26
Unlock()27 void Mutex::Unlock() {
28 mu_.Release();
29 }
30
AssertHeld()31 void Mutex::AssertHeld() {
32 mu_.AssertAcquired();
33 }
34
CondVar(Mutex * mu)35 CondVar::CondVar(Mutex* mu)
36 : cv_(&mu->mu_) {
37 }
38
~CondVar()39 CondVar::~CondVar() { }
40
Wait()41 void CondVar::Wait() {
42 cv_.Wait();
43 }
44
Signal()45 void CondVar::Signal(){
46 cv_.Signal();
47 }
48
SignalAll()49 void CondVar::SignalAll() {
50 cv_.Broadcast();
51 }
52
InitOnceImpl(OnceType * once,void (* initializer)())53 void InitOnceImpl(OnceType* once, void (*initializer)()) {
54 OnceType state = ::base::subtle::Acquire_Load(once);
55 if (state == ONCE_STATE_DONE)
56 return;
57
58 state = ::base::subtle::NoBarrier_CompareAndSwap(
59 once,
60 ONCE_STATE_UNINITIALIZED,
61 ONCE_STATE_EXECUTING_CLOSURE);
62
63 if (state == ONCE_STATE_UNINITIALIZED) {
64 // We are the first thread, we have to call the closure.
65 (*initializer)();
66 ::base::subtle::Release_Store(once, ONCE_STATE_DONE);
67 } else {
68 // Another thread is running the closure, wait until completion.
69 while (state == ONCE_STATE_EXECUTING_CLOSURE) {
70 ::base::PlatformThread::YieldCurrentThread();
71 state = ::base::subtle::Acquire_Load(once);
72 }
73 }
74 }
75
Snappy_Compress(const char * input,size_t input_length,std::string * output)76 bool Snappy_Compress(const char* input, size_t input_length,
77 std::string* output) {
78 #if defined(USE_SNAPPY)
79 output->resize(snappy::MaxCompressedLength(input_length));
80 size_t outlen;
81 snappy::RawCompress(input, input_length, &(*output)[0], &outlen);
82 output->resize(outlen);
83 return true;
84 #else
85 return false;
86 #endif
87 }
88
Snappy_GetUncompressedLength(const char * input_data,size_t input_length,size_t * result)89 bool Snappy_GetUncompressedLength(const char* input_data,
90 size_t input_length,
91 size_t* result) {
92 #if defined(USE_SNAPPY)
93 return snappy::GetUncompressedLength(input_data, input_length, result);
94 #else
95 return false;
96 #endif
97 }
98
Snappy_Uncompress(const char * input_data,size_t input_length,char * output)99 bool Snappy_Uncompress(const char* input_data, size_t input_length,
100 char* output) {
101 #if defined(USE_SNAPPY)
102 return snappy::RawUncompress(input_data, input_length, output);
103 #else
104 return false;
105 #endif
106 }
107
108 }
109 }
110