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
|
/*
* This code is derived from uClibc (original license follows).
* https://git.uclibc.org/uClibc/tree/utils/mmap-windows.c
*/
/* mmap() replacement for Windows
*
* Author: Mike Frysinger <vapier@gentoo.org>
* Placed into the public domain
*/
/* References:
* CreateFileMapping: http://msdn.microsoft.com/en-us/library/aa366537(VS.85).aspx
* CloseHandle: http://msdn.microsoft.com/en-us/library/ms724211(VS.85).aspx
* MapViewOfFile: http://msdn.microsoft.com/en-us/library/aa366761(VS.85).aspx
* UnmapViewOfFile: http://msdn.microsoft.com/en-us/library/aa366882(VS.85).aspx
*/
#if defined(_WIN32)
#include "WindowsMMap.h"
#define WIN32_LEAN_AND_MEAN
#include <windows.h>
#include "InstrProfiling.h"
#ifdef __USE_FILE_OFFSET64
# define DWORD_HI(x) (x >> 32)
# define DWORD_LO(x) ((x) & 0xffffffff)
#else
# define DWORD_HI(x) (0)
# define DWORD_LO(x) (x)
#endif
COMPILER_RT_VISIBILITY
void *mmap(void *start, size_t length, int prot, int flags, int fd, off_t offset)
{
if (prot & ~(PROT_READ | PROT_WRITE | PROT_EXEC))
return MAP_FAILED;
if (fd == -1) {
if (!(flags & MAP_ANON) || offset)
return MAP_FAILED;
} else if (flags & MAP_ANON)
return MAP_FAILED;
DWORD flProtect;
if (prot & PROT_WRITE) {
if (prot & PROT_EXEC)
flProtect = PAGE_EXECUTE_READWRITE;
else
flProtect = PAGE_READWRITE;
} else if (prot & PROT_EXEC) {
if (prot & PROT_READ)
flProtect = PAGE_EXECUTE_READ;
else if (prot & PROT_EXEC)
flProtect = PAGE_EXECUTE;
} else
flProtect = PAGE_READONLY;
off_t end = length + offset;
HANDLE mmap_fd, h;
if (fd == -1)
mmap_fd = INVALID_HANDLE_VALUE;
else
mmap_fd = (HANDLE)_get_osfhandle(fd);
h = CreateFileMapping(mmap_fd, NULL, flProtect, DWORD_HI(end), DWORD_LO(end), NULL);
if (h == NULL)
return MAP_FAILED;
DWORD dwDesiredAccess;
if (prot & PROT_WRITE)
dwDesiredAccess = FILE_MAP_WRITE;
else
dwDesiredAccess = FILE_MAP_READ;
if (prot & PROT_EXEC)
dwDesiredAccess |= FILE_MAP_EXECUTE;
if (flags & MAP_PRIVATE)
dwDesiredAccess |= FILE_MAP_COPY;
void *ret = MapViewOfFile(h, dwDesiredAccess, DWORD_HI(offset), DWORD_LO(offset), length);
if (ret == NULL) {
CloseHandle(h);
ret = MAP_FAILED;
}
return ret;
}
COMPILER_RT_VISIBILITY
void munmap(void *addr, size_t length)
{
UnmapViewOfFile(addr);
/* ruh-ro, we leaked handle from CreateFileMapping() ... */
}
COMPILER_RT_VISIBILITY
int msync(void *addr, size_t length, int flags)
{
if (flags & MS_INVALIDATE)
return -1; /* Not supported. */
/* Exactly one of MS_ASYNC or MS_SYNC must be specified. */
switch (flags & (MS_ASYNC | MS_SYNC)) {
case MS_SYNC:
case MS_ASYNC:
break;
default:
return -1;
}
if (!FlushViewOfFile(addr, length))
return -1;
if (flags & MS_SYNC) {
/* FIXME: No longer have access to handle from CreateFileMapping(). */
/*
* if (!FlushFileBuffers(h))
* return -1;
*/
}
return 0;
}
COMPILER_RT_VISIBILITY
int lock(HANDLE handle, DWORD lockType, BOOL blocking) {
DWORD flags = lockType;
if (!blocking)
flags |= LOCKFILE_FAIL_IMMEDIATELY;
OVERLAPPED overlapped;
ZeroMemory(&overlapped, sizeof(OVERLAPPED));
overlapped.hEvent = CreateEvent(NULL, FALSE, FALSE, NULL);
BOOL result = LockFileEx(handle, flags, 0, MAXDWORD, MAXDWORD, &overlapped);
if (!result) {
DWORD dw = GetLastError();
// In non-blocking mode, return an error if the file is locked.
if (!blocking && dw == ERROR_LOCK_VIOLATION)
return -1; // EWOULDBLOCK
// If the error is ERROR_IO_PENDING, we need to wait until the operation
// finishes. Otherwise, we return an error.
if (dw != ERROR_IO_PENDING)
return -1;
DWORD dwNumBytes;
if (!GetOverlappedResult(handle, &overlapped, &dwNumBytes, TRUE))
return -1;
}
return 0;
}
COMPILER_RT_VISIBILITY
int flock(int fd, int operation) {
HANDLE handle = (HANDLE)_get_osfhandle(fd);
if (handle == INVALID_HANDLE_VALUE)
return -1;
BOOL blocking = (operation & LOCK_NB) == 0;
int op = operation & ~LOCK_NB;
switch (op) {
case LOCK_EX:
return lock(handle, LOCKFILE_EXCLUSIVE_LOCK, blocking);
case LOCK_SH:
return lock(handle, 0, blocking);
case LOCK_UN:
if (!UnlockFile(handle, 0, 0, MAXDWORD, MAXDWORD))
return -1;
break;
default:
return -1;
}
return 0;
}
#undef DWORD_HI
#undef DWORD_LO
#endif /* _WIN32 */
|
