cosmopolitan/libc/calls/dup-nt.c

54 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 │
│ │
│ Permission to use, copy, modify, and/or distribute this software for │
│ any purpose with or without fee is hereby granted, provided that the │
│ above copyright notice and this permission notice appear in all copies. │
│ │
│ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL │
│ WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED │
│ WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE │
│ AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL │
│ DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR │
│ PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER │
│ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR │
│ PERFORMANCE OF THIS SOFTWARE. │
╚─────────────────────────────────────────────────────────────────────────────*/
#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 = __getemptyfd()) == -1) {
return -1;
}
} else if (__ensurefds(newfd) != -1) {
if (g_fds.p[newfd].kind != kFdEmpty) {
close(newfd);
}
} else {
return -1;
}
if (DuplicateHandle(GetCurrentProcess(), g_fds.p[oldfd].handle,
GetCurrentProcess(), &g_fds.p[newfd].handle, 0, true,
kNtDuplicateSameAccess)) {
g_fds.p[newfd].kind = g_fds.p[oldfd].kind;
g_fds.p[newfd].flags = flags;
return newfd;
} else {
return __winerr();
}
}