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60 lines
1.7 KiB
C
60 lines
1.7 KiB
C
/*
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* Created on Fri Aug 07 2020
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*
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* This file is a part of Skytable
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* Skytable (formerly known as TerrabaseDB or Skybase) is a free and open-source
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* NoSQL database written by Sayan Nandan ("the Author") with the
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* vision to provide flexibility in data modelling without compromising
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* on performance, queryability or scalability.
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*
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* Copyright (c) 2020, Sayan Nandan <ohsayan@outlook.com>
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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 Affero General Public License as published by
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* the Free Software Foundation, either version 3 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU Affero General Public License for more details.
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*
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* You should have received a copy of the GNU Affero General Public License
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* along with this program. If not, see <https://www.gnu.org/licenses/>.
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*
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*/
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#include <errno.h>
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#include <sys/file.h>
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/* Acquire an exclusive lock for a file with the given descriptor */
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int lock_exclusive(int descriptor) {
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if (descriptor < 0) {
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return EBADF;
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}
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if (flock(descriptor, LOCK_EX) == -1) {
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return errno;
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}
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return 0;
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}
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int try_lock_exclusive(int descriptor) {
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if (descriptor < 0) {
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return EBADF;
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}
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if (flock(descriptor, LOCK_EX | LOCK_NB) == -1) {
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return errno;
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}
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return 0;
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}
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/* Unlock a file with the given descriptor */
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int unlock(int descriptor) {
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if (descriptor < 0) {
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return EBADF;
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}
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if (flock(descriptor, LOCK_UN) == -1) {
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return errno;
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}
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return 0;
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} |