cosmopolitan/libc/calls/flock-nt.c

45 lines
2.7 KiB
C

/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi│
╞══════════════════════════════════════════════════════════════════════════════╡
│ Copyright 2020 Justine Alexandra Roberts Tunney │
│ │
│ This program is free software; you can redistribute it and/or modify │
│ it under the terms of the GNU General Public License as published by │
│ the Free Software Foundation; version 2 of the License. │
│ │
│ This program is distributed in the hope that it will be useful, but │
│ WITHOUT ANY WARRANTY; without even the implied warranty of │
│ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU │
│ General Public License for more details. │
│ │
│ You should have received a copy of the GNU General Public License │
│ along with this program; if not, write to the Free Software │
│ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA │
│ 02110-1301 USA │
╚─────────────────────────────────────────────────────────────────────────────*/
#include "libc/calls/internal.h"
#include "libc/nt/files.h"
#include "libc/nt/runtime.h"
#include "libc/nt/struct/byhandlefileinformation.h"
#include "libc/nt/struct/overlapped.h"
#include "libc/str/str.h"
#include "libc/sysv/consts/lock.h"
#include "libc/sysv/errfuns.h"
textwindows int flock$nt(int fd, int op) {
struct NtOverlapped ov;
struct NtByHandleFileInformation info;
if (!__isfdkind(fd, kFdFile)) return ebadf();
memset(&ov, 0, sizeof(ov));
if (GetFileInformationByHandle(g_fds.p[fd].handle, &info) &&
((!(op & LOCK_UN) &&
LockFileEx(g_fds.p[fd].handle, op, 0, info.nFileSizeLow,
info.nFileSizeHigh, &ov)) ||
((op & LOCK_UN) && UnlockFileEx(g_fds.p[fd].handle, 0, info.nFileSizeLow,
info.nFileSizeHigh, &ov)))) {
return 0;
} else {
return __winerr();
}
}