diff options
| -rw-r--r-- | compat/win32mmap.c | 31 |
1 files changed, 18 insertions, 13 deletions
diff --git a/compat/win32mmap.c b/compat/win32mmap.c index 80a8c9af4f..519d51f2b6 100644 --- a/compat/win32mmap.c +++ b/compat/win32mmap.c @@ -2,37 +2,42 @@ void *git_mmap(void *start, size_t length, int prot, int flags, int fd, off_t offset) { - HANDLE hmap; + HANDLE osfhandle, hmap; void *temp; - off_t len; - struct stat st; + LARGE_INTEGER len; uint64_t o = offset; uint32_t l = o & 0xFFFFFFFF; uint32_t h = (o >> 32) & 0xFFFFFFFF; - if (!fstat(fd, &st)) - len = st.st_size; - else + osfhandle = (HANDLE)_get_osfhandle(fd); + if (!GetFileSizeEx(osfhandle, &len)) die("mmap: could not determine filesize"); - if ((length + offset) > len) - length = xsize_t(len - offset); + if ((length + offset) > len.QuadPart) + length = xsize_t(len.QuadPart - offset); if (!(flags & MAP_PRIVATE)) die("Invalid usage of mmap when built with USE_WIN32_MMAP"); - hmap = CreateFileMapping((HANDLE)_get_osfhandle(fd), NULL, - PAGE_WRITECOPY, 0, 0, NULL); + hmap = CreateFileMapping(osfhandle, NULL, + prot == PROT_READ ? PAGE_READONLY : PAGE_WRITECOPY, 0, 0, NULL); - if (!hmap) + if (!hmap) { + errno = EINVAL; return MAP_FAILED; + } - temp = MapViewOfFileEx(hmap, FILE_MAP_COPY, h, l, length, start); + temp = MapViewOfFileEx(hmap, prot == PROT_READ ? + FILE_MAP_READ : FILE_MAP_COPY, h, l, length, start); if (!CloseHandle(hmap)) warning("unable to close file mapping handle"); - return temp ? temp : MAP_FAILED; + if (temp) + return temp; + + errno = GetLastError() == ERROR_COMMITMENT_LIMIT ? EFBIG : EINVAL; + return MAP_FAILED; } int git_munmap(void *start, size_t length) |