| /* 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 |
| */ |
| |
| #include <io.h> |
| #include <windows.h> |
| #include <sys/types.h> |
| |
| #define PROT_READ 0x1 |
| #define PROT_WRITE 0x2 |
| /* This flag is only available in WinXP+ */ |
| #ifdef FILE_MAP_EXECUTE |
| #define PROT_EXEC 0x4 |
| #else |
| #define PROT_EXEC 0x0 |
| #define FILE_MAP_EXECUTE 0 |
| #endif |
| |
| #define MAP_SHARED 0x01 |
| #define MAP_PRIVATE 0x02 |
| #define MAP_ANONYMOUS 0x20 |
| #define MAP_ANON MAP_ANONYMOUS |
| #define MAP_FAILED ((void *) -1) |
| |
| #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 |
| |
| static 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; |
| } |
| |
| static void munmap(void *addr, size_t length) |
| { |
| UnmapViewOfFile(addr); |
| /* ruh-ro, we leaked handle from CreateFileMapping() ... */ |
| } |
| |
| #undef DWORD_HI |
| #undef DWORD_LO |