cosmopolitan/libc/calls/dup-nt.c

55 lines
2.9 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/bits/bits.h"
#include "libc/calls/calls.h"
#include "libc/calls/internal.h"
#include "libc/mem/mem.h"
#include "libc/nt/files.h"
#include "libc/nt/runtime.h"
#include "libc/sysv/consts/o.h"
#include "libc/sysv/errfuns.h"
/**
* Implements dup(), dup2(), and dup3() for Windows NT.
*/
textwindows int dup$nt(int oldfd, int newfd, int flags) {
if (!isfdkind(oldfd, kFdFile)) return ebadf();
if (newfd == -1) {
if ((newfd = createfd()) == -1) return -1;
} else if (isfdindex(newfd)) {
if (g_fds.p[newfd].kind != kFdEmpty) {
close(newfd);
}
} else {
do {
if (growfds() == -1) return -1;
} while (newfd >= g_fds.n);
}
if (DuplicateHandle(GetCurrentProcess(), g_fds.p[oldfd].handle,
GetCurrentProcess(), &g_fds.p[newfd].handle, 0,
flags & O_CLOEXEC, kNtDuplicateSameAccess)) {
g_fds.p[newfd].kind = g_fds.p[oldfd].kind;
g_fds.p[newfd].flags = flags;
return newfd;
} else {
return winerr();
}
}