57 lines
1.2 KiB
C
57 lines
1.2 KiB
C
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/* ==== file.c ============================================================
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* Copyright (c) 1993 by Chris Provenzano, proven@athena.mit.edu
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*
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* Description : All the new stdio functions.
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*
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* 1.00 93/09/04 proven
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* -Started coding this file.
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*/
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#include <pthread/copyright.h>
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#include "pthread.h"
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#include <stdio.h> /* Remove this when the stdio library is done. */
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/* ==========================================================================
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* flockfile()
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*/
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void flockfile(FILE *fp)
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{
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semaphore *lock;
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int fd;
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fd = fileno(fp);
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lock = &(fd_table[fd]->lock);
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while (SEMAPHORE_TEST_AND_SET(lock)) {
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pthread_yield();
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}
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if (fd_table[fd]->r_owner != pthread_run) {
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fd_basic_lock(fd, FD_RDWR, lock);
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}
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fd_table[fd]->lockcount++;
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SEMAPHORE_RESET(lock);
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}
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/* ==========================================================================
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* funlockfile()
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*/
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void funlockfile(FILE *fp)
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{
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semaphore *lock;
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int fd;
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fd = fileno(fp);
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lock = &(fd_table[fd]->lock);
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while (SEMAPHORE_TEST_AND_SET(lock)) {
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pthread_yield();
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}
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if (fd_table[fd]->r_owner == pthread_run) {
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if (--fd_table[fd]->lockcount == 0) {
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fd_basic_unlock(fd, FD_RDWR);
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}
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}
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SEMAPHORE_RESET(lock);
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}
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