1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
|
/* Copyright (c) 2013 Stanislaw Halik <sthalik@misaki.pl>
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*/
#include "shm.h"
#if defined _WIN32
#include <cstring>
#include <stdio.h>
#include <accctrl.h>
#include <aclapi.h>
#if !defined __WINE__
# include <QDebug>
# define warn(str, ...) (qDebug() << "shm:" str ": " << __VA_ARGS__)
#else
# define warn(str, ...) (void)0
#endif
shm_wrapper::shm_wrapper(const char* shm_name, const char* mutex_name, int map_size)
{
if (mutex_name == nullptr)
mutex = nullptr;
else
{
mutex = CreateMutexA(nullptr, false, mutex_name);
if (!mutex)
{
warn("CreateMutexA", (int) GetLastError());
return;
}
}
mapped_file = CreateFileMappingA(
INVALID_HANDLE_VALUE,
nullptr,
PAGE_READWRITE,
0,
map_size,
shm_name);
if (!mapped_file)
{
warn("CreateFileMappingA", (int) GetLastError());
return;
}
mem = MapViewOfFile(mapped_file,
FILE_MAP_WRITE,
0,
0,
map_size);
if (!mem)
warn("MapViewOfFile:", (int) GetLastError());
}
shm_wrapper::~shm_wrapper()
{
if (mem && !UnmapViewOfFile(mem))
goto fail;
if (mapped_file && !CloseHandle(mapped_file))
goto fail;
if (mutex && !CloseHandle(mutex))
goto fail;
return;
fail:
warn("failed to close mapping", (int) GetLastError());
}
bool shm_wrapper::lock()
{
if (mutex)
return WaitForSingleObject(mutex, INFINITE) == WAIT_OBJECT_0;
else
return false;
}
bool shm_wrapper::unlock()
{
if (mutex)
return ReleaseMutex(mutex);
else
return false;
}
#else
#include <limits.h>
#pragma GCC diagnostic ignored "-Wunused-result"
shm_wrapper::shm_wrapper(const char *shm_name, const char* /*mutex_name*/, int map_size) : size(map_size)
{
char filename[PATH_MAX+2] {};
strcpy(filename, "/");
strcat(filename, shm_name);
fd = shm_open(filename, O_RDWR | O_CREAT, 0600);
(void) ftruncate(fd, map_size);
mem = mmap(NULL, map_size, PROT_READ|PROT_WRITE, MAP_SHARED, fd, (off_t)0);
}
shm_wrapper::~shm_wrapper()
{
(void) munmap(mem, size);
(void) close(fd);
}
bool shm_wrapper::lock()
{
return flock(fd, LOCK_EX) == 0;
}
bool shm_wrapper::unlock()
{
return flock(fd, LOCK_UN) == 0;
}
#endif
bool shm_wrapper::success()
{
#ifndef _WIN32
return mem != (void*) -1;
#else
return mem != NULL;
#endif
}
|
