46 lines
2.5 KiB
C
46 lines
2.5 KiB
C
/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
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│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi│
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╞══════════════════════════════════════════════════════════════════════════════╡
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│ Copyright 2020 Justine Alexandra Roberts Tunney │
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│ │
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│ This program is free software; you can redistribute it and/or modify │
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│ it under the terms of the GNU General Public License as published by │
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│ the Free Software Foundation; version 2 of the License. │
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│ │
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│ This program is distributed in the hope that it will be useful, but │
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│ WITHOUT ANY WARRANTY; without even the implied warranty of │
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│ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU │
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│ General Public License for more details. │
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│ │
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│ You should have received a copy of the GNU General Public License │
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│ along with this program; if not, write to the Free Software │
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│ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA │
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│ 02110-1301 USA │
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╚─────────────────────────────────────────────────────────────────────────────*/
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#include "libc/calls/calls.h"
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#include "libc/calls/internal.h"
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#include "libc/calls/struct/iovec.h"
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#include "libc/errno.h"
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/**
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* Transfers memory to pipe.
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*
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* @param flags can have SPLICE_F_{MOVE,NONBLOCK,MORE,GIFT}
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* @return number of bytes actually transferred, or -1 w/ errno
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*/
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ssize_t vmsplice(int fd, const struct iovec *chunks, int64_t count,
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uint32_t flags) {
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int olderr;
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ssize_t wrote;
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olderr = errno;
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if ((wrote = vmsplice$sysv(fd, chunks, count, flags)) == -1) {
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errno = olderr;
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if (count) {
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wrote = write(fd, chunks[0].iov_base, chunks[0].iov_len);
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} else {
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wrote = write(fd, NULL, 0);
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}
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}
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return wrote;
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}
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