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 // See port_example.h for documentation for the following types/functions.
6
7 #ifndef STORAGE_LEVELDB_PORT_PORT_POSIX_H_
8 #define STORAGE_LEVELDB_PORT_PORT_POSIX_H_
9
10 #undef PLATFORM_IS_LITTLE_ENDIAN
11 #if defined(OS_MACOSX)
12 #include <machine/endian.h>
13 #if defined(__DARWIN_LITTLE_ENDIAN) && defined(__DARWIN_BYTE_ORDER)
14 #define PLATFORM_IS_LITTLE_ENDIAN \
15 (__DARWIN_BYTE_ORDER == __DARWIN_LITTLE_ENDIAN)
16 #endif
17 #elif defined(OS_SOLARIS)
18 #include <sys/isa_defs.h>
19 #ifdef _LITTLE_ENDIAN
20 #define PLATFORM_IS_LITTLE_ENDIAN true
21 #else
22 #define PLATFORM_IS_LITTLE_ENDIAN false
23 #endif
24 #elif defined(OS_FREEBSD)
25 #include <sys/types.h>
26 #include <sys/endian.h>
27 #define PLATFORM_IS_LITTLE_ENDIAN (_BYTE_ORDER == _LITTLE_ENDIAN)
28 #elif defined(OS_OPENBSD) || defined(OS_NETBSD) ||\
29 defined(OS_DRAGONFLYBSD)
30 #include <sys/types.h>
31 #include <sys/endian.h>
32 #elif defined(OS_HPUX)
33 #define PLATFORM_IS_LITTLE_ENDIAN false
34 #elif defined(OS_ANDROID)
35 // Due to a bug in the NDK x86 <sys/endian.h> definition,
36 // _BYTE_ORDER must be used instead of __BYTE_ORDER on Android.
37 // See http://code.google.com/p/android/issues/detail?id=39824
38 #include <endian.h>
39 #define PLATFORM_IS_LITTLE_ENDIAN (_BYTE_ORDER == _LITTLE_ENDIAN)
40 #else
41 #include <endian.h>
42 #endif
43
44 #include <pthread.h>
45 #ifdef SNAPPY
46 #include <snappy.h>
47 #endif
48 #include <stdint.h>
49 #include <string>
50 #include "port/atomic_pointer.h"
51
52 #ifndef PLATFORM_IS_LITTLE_ENDIAN
53 #define PLATFORM_IS_LITTLE_ENDIAN (__BYTE_ORDER == __LITTLE_ENDIAN)
54 #endif
55
56 #if defined(OS_MACOSX) || defined(OS_SOLARIS) || defined(OS_FREEBSD) ||\
57 defined(OS_NETBSD) || defined(OS_OPENBSD) || defined(OS_DRAGONFLYBSD) ||\
58 defined(OS_ANDROID) || defined(OS_HPUX)
59 // Use fread/fwrite/fflush on platforms without _unlocked variants
60 #define fread_unlocked fread
61 #define fwrite_unlocked fwrite
62 #define fflush_unlocked fflush
63 #endif
64
65 #if defined(OS_MACOSX) || defined(OS_FREEBSD) ||\
66 defined(OS_OPENBSD) || defined(OS_DRAGONFLYBSD)
67 // Use fsync() on platforms without fdatasync()
68 #define fdatasync fsync
69 #endif
70
71 #if defined(OS_ANDROID) && __ANDROID_API__ < 9
72 // fdatasync() was only introduced in API level 9 on Android. Use fsync()
73 // when targetting older platforms.
74 #define fdatasync fsync
75 #endif
76
77 namespace leveldb {
78 namespace port {
79
80 static const bool kLittleEndian = PLATFORM_IS_LITTLE_ENDIAN;
81 #undef PLATFORM_IS_LITTLE_ENDIAN
82
83 class CondVar;
84
85 class Mutex {
86 public:
87 Mutex();
88 ~Mutex();
89
90 void Lock();
91 void Unlock();
AssertHeld()92 void AssertHeld() { }
93
94 private:
95 friend class CondVar;
96 pthread_mutex_t mu_;
97
98 // No copying
99 Mutex(const Mutex&);
100 void operator=(const Mutex&);
101 };
102
103 class CondVar {
104 public:
105 explicit CondVar(Mutex* mu);
106 ~CondVar();
107 void Wait();
108 void Signal();
109 void SignalAll();
110 private:
111 pthread_cond_t cv_;
112 Mutex* mu_;
113 };
114
115 typedef pthread_once_t OnceType;
116 #define LEVELDB_ONCE_INIT PTHREAD_ONCE_INIT
117 extern void InitOnce(OnceType* once, void (*initializer)());
118
Snappy_Compress(const char * input,size_t length,::std::string * output)119 inline bool Snappy_Compress(const char* input, size_t length,
120 ::std::string* output) {
121 #ifdef SNAPPY
122 output->resize(snappy::MaxCompressedLength(length));
123 size_t outlen;
124 snappy::RawCompress(input, length, &(*output)[0], &outlen);
125 output->resize(outlen);
126 return true;
127 #endif
128
129 return false;
130 }
131
Snappy_GetUncompressedLength(const char * input,size_t length,size_t * result)132 inline bool Snappy_GetUncompressedLength(const char* input, size_t length,
133 size_t* result) {
134 #ifdef SNAPPY
135 return snappy::GetUncompressedLength(input, length, result);
136 #else
137 return false;
138 #endif
139 }
140
Snappy_Uncompress(const char * input,size_t length,char * output)141 inline bool Snappy_Uncompress(const char* input, size_t length,
142 char* output) {
143 #ifdef SNAPPY
144 return snappy::RawUncompress(input, length, output);
145 #else
146 return false;
147 #endif
148 }
149
GetHeapProfile(void (* func)(void *,const char *,int),void * arg)150 inline bool GetHeapProfile(void (*func)(void*, const char*, int), void* arg) {
151 return false;
152 }
153
154 } // namespace port
155 } // namespace leveldb
156
157 #endif // STORAGE_LEVELDB_PORT_PORT_POSIX_H_
158