+ if (size < old_size.QuadPart)
+ {
+ /* Reduce the size. */
+ LONG size_hi = (LONG) (size >> 32);
+ if (SetFilePointer (tmph, (LONG) size, &size_hi, FILE_BEGIN)
+ == INVALID_SET_FILE_POINTER
+ && GetLastError() != NO_ERROR)
+ {
+ CloseHandle (tmph);
+ return FALSE;
+ }
+ if (!SetEndOfFile (tmph))
+ {
+ CloseHandle (tmph);
+ return FALSE;
+ }
+ }
+ else
+ {
+ /* Increase the size by adding zero bytes at the end. */
+ static char zero_bytes[1024];
+ LONG pos_hi = 0;
+ LONG pos_lo = SetFilePointer (tmph, (LONG) 0, &pos_hi, FILE_END);
+ LONGLONG pos;
+ if (pos_lo == INVALID_SET_FILE_POINTER
+ && GetLastError() != NO_ERROR)
+ {
+ CloseHandle (tmph);
+ return FALSE;
+ }
+ pos = ((LONGLONG) pos_hi << 32) | (ULONGLONG) (ULONG) pos_lo;
+ while (pos < size)
+ {
+ DWORD written;
+ LONGLONG count = size - pos;
+ if (count > sizeof (zero_bytes))
+ count = sizeof (zero_bytes);
+ if (!WriteFile (tmph, zero_bytes, (DWORD) count, &written, NULL)
+ || written == 0)
+ {
+ CloseHandle (tmph);
+ return FALSE;
+ }
+ pos += (ULONGLONG) (ULONG) written;
+ }
+ }
+ /* Close the handle. */
+ CloseHandle (tmph);
+ }
+ return TRUE;
+}
+
+int
+ftruncate (int fd, off_t length)
+{
+ HANDLE handle = (HANDLE) _get_osfhandle (fd);
+
+ if (handle == INVALID_HANDLE_VALUE)
+ {
+ errno = EBADF;
+ return -1;
+ }
+ if (length < 0)
+ {
+ errno = EINVAL;
+ return -1;
+ }
+ if (!SetFileSize (handle, length))
+ {
+ switch (GetLastError ())
+ {
+ case ERROR_ACCESS_DENIED:
+ errno = EACCES;
+ break;
+ case ERROR_HANDLE_DISK_FULL:
+ case ERROR_DISK_FULL:
+ case ERROR_DISK_TOO_FRAGMENTED:
+ errno = ENOSPC;
+ break;
+ default:
+ errno = EIO;
+ break;
+ }
+ return -1;
+ }
+ return 0;
+}
+
+# else
+
+# include <io.h>
+
+# if HAVE_MSVC_INVALID_PARAMETER_HANDLER
+# include "msvc-inval.h"
+static int
+chsize_nothrow (int fd, long length)
+{
+ int result;
+
+ TRY_MSVC_INVAL
+ {
+ result = chsize (fd, length);
+ }
+ CATCH_MSVC_INVAL
+ {
+ result = -1;
+ errno = EBADF;
+ }
+ DONE_MSVC_INVAL;
+
+ return result;
+}
+# define chsize chsize_nothrow
+# endif