45 lines
2.6 KiB
C
45 lines
2.6 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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│ Permission to use, copy, modify, and/or distribute this software for │
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│ any purpose with or without fee is hereby granted, provided that the │
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│ above copyright notice and this permission notice appear in all copies. │
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│ │
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│ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL │
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│ WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED │
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│ WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE │
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│ AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL │
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│ DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR │
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│ PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER │
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│ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR │
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│ PERFORMANCE OF THIS SOFTWARE. │
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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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