92 lines
3.1 KiB
C
92 lines
3.1 KiB
C
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/*---
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This software is copyrighted by the Regents of the University of
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California, and other parties. The following terms apply to all files
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associated with the software unless explicitly disclaimed in
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individual files.
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The authors hereby grant permission to use, copy, modify, distribute,
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and license this software and its documentation for any purpose,
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provided that existing copyright notices are retained in all copies
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and that this notice is included verbatim in any distributions. No
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written agreement, license, or royalty fee is required for any of the
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authorized uses. Modifications to this software may be copyrighted by
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their authors and need not follow the licensing terms described here,
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provided that the new terms are clearly indicated on the first page of
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each file where they apply.
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IN NO EVENT SHALL THE AUTHORS OR DISTRIBUTORS BE LIABLE TO ANY PARTY
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FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
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ARISING OUT OF THE USE OF THIS SOFTWARE, ITS DOCUMENTATION, OR ANY
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DERIVATIVES THEREOF, EVEN IF THE AUTHORS HAVE BEEN ADVISED OF THE
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POSSIBILITY OF SUCH DAMAGE.
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THE AUTHORS AND DISTRIBUTORS SPECIFICALLY DISCLAIM ANY WARRANTIES,
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INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
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MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, AND
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NON-INFRINGEMENT. THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, AND
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THE AUTHORS AND DISTRIBUTORS HAVE NO OBLIGATION TO PROVIDE
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MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
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GOVERNMENT USE: If you are acquiring this software on behalf of the
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U.S. government, the Government shall have only "Restricted Rights" in
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the software and related documentation as defined in the Federal
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Acquisition Regulations (FARs) in Clause 52.227.19 (c) (2). If you are
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acquiring the software on behalf of the Department of Defense, the
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software shall be classified as "Commercial Computer Software" and the
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Government shall have only "Restricted Rights" as defined in Clause
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252.227-7013 (c) (1) of DFARs. Notwithstanding the foregoing, the
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authors grant the U.S. Government and others acting in its behalf
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permission to use and distribute the software in accordance with the
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terms specified in this license.
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---*/
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/*
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* File : rw.c
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*
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* Title : Demo Readers/Writer.
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*
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* Short : A solution to the multi-reader's, one writer problem.
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*
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* Long :
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*
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* Author : Andrae Muys
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*
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* Date : 18 September 1997
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*
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* Revised : 4-7-04 Shamelessly stolen and adapted by Rusty Sears.
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* Found the code at this url:
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* http://www.cs.nmsu.edu/~jcook/Tools/pthreads/rw.c
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*/
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#include <stdlib.h>
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#include <pthread.h>
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#include <stdio.h>
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#include <unistd.h>
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typedef struct {
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pthread_mutex_t *mut;
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int writers;
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int readers;
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int waiting;
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pthread_cond_t *writeOK, *readOK;
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} rwl;
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rwl *initlock (void);
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void readlock (rwl *lock, int d);
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void writelock (rwl *lock, int d);
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void readunlock (rwl *lock);
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void writeunlock (rwl *lock);
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void deletelock (rwl *lock);
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/*
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typedef struct {
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rwl *lock;
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int id;
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long delay;
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} rwargs;
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rwargs *newRWargs (rwl *l, int i, long d);
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void *reader (void *args);
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void *writer (void *args);
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*/
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