void protect_range(void *start, unsigned long len, unsigned long prot)
{
uintptr_t curr = (uintptr_t)start & PAGE_MASK;
len &= PAGE_MASK;
for (; len; len -= PAGE_SIZE, curr += PAGE_SIZE)
protect_page((void *)curr, prot);
}
void* mmap(void* addr, size_t len, int prot, int flags, int fildes, oft__ off)
{
#ifdef _MSC_VER
#pragma warning(push)
#pragma warning(disable: 4293)
#endif
const DWORD access = protect_file(prot);
const DWORD protect = protect_page(prot);
const oft__ max = off + (oft__)len;
const DWORD max_lo = large ? (DWORD)((max) & MAXDWORD) : (DWORD)max;
const DWORD max_hi = large ? (DWORD)((max >> 32) & MAXDWORD) : (DWORD)0;
const DWORD file_lo = large ? (DWORD)((off) & MAXDWORD) : (DWORD)off;
const DWORD file_hi = large ? (DWORD)((off >> 32) & MAXDWORD) : (DWORD)0;
#ifdef _MSC_VER
#pragma warning(pop)
#endif
if (len == 0 || (flags & MAP_FIXED) != 0 || prot == PROT_EXEC)
{
errno = EINVAL;
return MAP_FAILED;
}
const HANDLE handle = ((flags & MAP_ANONYMOUS) == 0) ?
(HANDLE)_get_osfhandle(fildes) : INVALID_HANDLE_VALUE;
if ((flags & MAP_ANONYMOUS) == 0 && handle == INVALID_HANDLE_VALUE)
{
errno = EBADF;
return MAP_FAILED;
}
const HANDLE mapping = CreateFileMappingW(handle, NULL, protect, max_hi,
max_lo, NULL);
if (mapping == NULL)
{
errno = last_error(EPERM);
return MAP_FAILED;
}
const LPVOID map = MapViewOfFile(mapping, access, file_hi, file_lo, len);
/* TODO: verify mapping handle may be closed here and then use the map. */
if (map == NULL || CloseHandle(mapping) == FALSE)
{
errno = last_error(EPERM);
return MAP_FAILED;
}
errno = 0;
return map;
}
int mprotect(void* addr, size_t len, int prot)
{
DWORD old_protect = 0;
const DWORD new_protect = protect_page(prot);
if (VirtualProtect(addr, len, new_protect, &old_protect) != FALSE)
{
errno = 0;
return 0;
}
errno = last_error(EPERM);
return -1;
}
