aboutsummaryrefslogtreecommitdiffstats
path: root/util/system/shmat.cpp
blob: 52cf01f6e0a978931f1555f029404e60c4cf7dcc (plain) (blame)
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
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
#include "shmat.h"
 
#include <util/generic/guid.h>
 
#if defined(_win_) 
    #include <stdio.h> 
    #include "winint.h" 
#elif defined(_bionic_) 
    #include <sys/types.h> 
    #include <sys/ipc.h> 
    #include <sys/syscall.h> 
#elif defined(_unix_) 
    #include <sys/types.h> 
    #include <sys/ipc.h> 
    #include <sys/shm.h> 
#endif 
 
#if defined(_cygwin_) 
    #define WINAPI __stdcall 
    #define FILE_MAP_ALL_ACCESS ((long)983071) 
    #define PAGE_READWRITE 4 
    #define FALSE 0 
 
extern "C" { 
    using HANDLE = OS_HANDLE; 
    using BOOL = int; 
    using DWORD = ui32; 
    using LPCTSTR = const char*; 
    using LPVOID = void*; 
    using LPCVOID = void const*; 
    using SIZE_T = size_t; 
 
    BOOL WINAPI CloseHandle(HANDLE hObject); 
    HANDLE WINAPI OpenFileMappingA(DWORD dwDesiredAccess, BOOL bInheritHandle, LPCTSTR lpName); 
    LPVOID WINAPI MapViewOfFile(HANDLE hFileMappingObject, DWORD DesiredAccess, DWORD FileOffsetHigh, DWORD FileOffsetLow, SIZE_T NumberOfBytesToMap); 
    HANDLE WINAPI CreateFileMappingA(HANDLE hFile, LPVOID lpAttributes, DWORD flProtect, DWORD MaximumSizeHigh, DWORD MaximumSizeLow, LPCTSTR lpName); 
    BOOL WINAPI UnmapViewOfFile(LPCVOID lpBaseAddress); 
    DWORD WINAPI GetLastError(void); 
} 
#endif

#if defined(_bionic_) 
namespace { 
    #if !defined(__i386__) 
    static int shmget(key_t key, size_t size, int flag) { 
        if (size > PTRDIFF_MAX) { 
            size = SIZE_MAX; 
        } 
 
        return syscall(__NR_shmget, key, size, flag); 
    } 
 
    static void* shmat(int id, const void* addr, int flag) { 
        return (void*)syscall(__NR_shmat, id, addr, flag); 
    } 
 
    static int shmctl(int id, int cmd, void* buf) { 
        return syscall(__NR_shmctl, id, cmd | IPC_64, buf); 
    } 
 
    static int shmdt(const void* addr) { 
        return syscall(__NR_shmdt, addr); 
    } 

    #else 
        #define IPCOP_shmat 21 
        #define IPCOP_shmdt 22 
        #define IPCOP_shmget 23 
        #define IPCOP_shmctl 24 

    static int shmget(key_t key, size_t size, int flag) {
        return syscall(__NR_ipc, IPCOP_shmget, key, size, flag, 0);
    }

    static void* shmat(int id, const void* addr, int flag) {
        void* retval;
        long res = syscall(__NR_ipc, IPCOP_shmat, id, flag, (long)&retval, addr);
        return (res >= 0) ? retval : (void*)-1; 
    }

    static int shmctl(int id, int cmd, void* buf) {
        return syscall(__NR_ipc, IPCOP_shmctl, id, cmd | IPC_64, 0, buf);
    }

    static int shmdt(const void* addr) {
        return syscall(__NR_ipc, IPCOP_shmdt, 0, 0, 0, addr);
    }
    #endif 
} 
#endif 
 
TSharedMemory::TSharedMemory()
    : Handle(INVALID_FHANDLE) 
    , Data(nullptr)
    , Size(0)
{
}

#if defined(_win_) 
static void FormatName(char* buf, const TGUID& id) { 
    sprintf(buf, "Global\\shmat-%s", GetGuidAsString(id).c_str());
}

bool TSharedMemory::Open(const TGUID& id, int size) { 
    //Y_ASSERT(Data == 0);
    Id = id;
    Size = size;

    char name[100];
    FormatName(name, Id);
    Handle = OpenFileMappingA(FILE_MAP_ALL_ACCESS, FALSE, name); 
 
    if (Handle == 0) { 
        return false;
    } 

    Data = MapViewOfFile(Handle, FILE_MAP_ALL_ACCESS, 0, 0, size); 
 
    if (Data == 0) {
        //Y_ASSERT(0);
        CloseHandle(Handle); 
        Handle = INVALID_OS_HANDLE; 
 
        return false;
    }
 
    return true;
}

bool TSharedMemory::Create(int size) { 
    //Y_ASSERT(Data == 0);
    Size = size;

    CreateGuid(&Id);

    char name[100];
    FormatName(name, Id);
    Handle = CreateFileMappingA(INVALID_OS_HANDLE, nullptr, PAGE_READWRITE, 0, size, name); 
 
    if (Handle == 0) { 
        //Y_ASSERT(0);
        return false;
    }

    Data = MapViewOfFile(Handle, FILE_MAP_ALL_ACCESS, 0, 0, size); 
 
    if (Data == 0) {
        //Y_ASSERT(0);
        CloseHandle(Handle); 
        Handle = INVALID_OS_HANDLE; 
 
        return false;
    }
 
    return true;
}

TSharedMemory::~TSharedMemory() { 
    if (Data) { 
        UnmapViewOfFile(Handle); 
    } 
 
    CloseHandle(Handle); 
}
#else
static key_t GetKey(const TGUID& id) { 
    i64 id64 = (ui64)(((ui64)id.dw[0] + (ui64)id.dw[2]) << 32) + (ui64)id.dw[1] + (ui64)id.dw[3]; 
 
    return id64;
}

bool TSharedMemory::Open(const TGUID& id, int size) { 
    Y_VERIFY(id, "invalid shared memory guid: %s", GetGuidAsString(id).data());

    //Y_ASSERT(Data == 0);
    Size = size;

    key_t k = GetKey(id);
    int shmId = shmget(k, Size, 0777); // do not fill Handle, since IPC_RMID should be called by owner 
 
    if (shmId < 0) { 
        return false;
    } 

    Data = shmat(shmId, nullptr, 0);
 
    if (Data == nullptr) {
        //Y_ASSERT(0);
        return false;
    }
 
    return true;
}

bool TSharedMemory::Create(int size) { 
    //Y_ASSERT(Data == 0);
    Size = size;

    CreateGuid(&Id);

    key_t k = GetKey(Id);
    Handle = shmget(k, Size, IPC_CREAT | IPC_EXCL | 0777); 
 
    if (Handle < 0) { 
        //Y_ASSERT(0);
        return false;
    }

    Data = shmat(Handle, nullptr, 0); 
 
    if (Data == (void*)-1) { 
        //Y_ASSERT(0);
        shmctl(Handle, IPC_RMID, nullptr); 
        Handle = -1; 
 
        return false;
    }
 
    return true;
}

TSharedMemory::~TSharedMemory() { 
    if (Data) { 
        shmdt(Data);
    } 
 
    if (Handle >= 0) { 
        shmctl(Handle, IPC_RMID, nullptr); 
    } 
}
#endif