46 lines
2.6 KiB
C
46 lines
2.6 KiB
C
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/*-*- 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/errno.h"
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/**
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* Flushes subset of file to disk.
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*
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* @param offset is page rounded
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* @param bytes is page rounded; 0 means until EOF
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* @param flags can have SYNC_FILE_RANGE_{WAIT_BEFORE,WRITE,WAIT_AFTER}
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* @note Linux documentation says this call is "dangerous"; for highest
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* assurance of data recovery after crash, consider fsync() on both
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* file and directory
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* @see fsync(), fdatasync(), PAGESIZE
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*/
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int sync_file_range(int fd, int64_t offset, int64_t bytes, unsigned flags) {
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int rc, olderr;
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olderr = errno;
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if ((rc = sync_file_range$sysv(fd, offset, bytes, flags)) != -1 ||
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errno != ENOSYS) {
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return rc;
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} else {
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errno = olderr;
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return fdatasync(fd);
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}
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}
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