mirror of
https://github.com/ioacademy-jikim/debugging
synced 2025-06-08 08:26:14 +00:00
104 lines
1.9 KiB
C
104 lines
1.9 KiB
C
#define _GNU_SOURCE
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#include <config.h>
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#include <errno.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <sys/ipc.h>
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#include <sys/sem.h>
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#include <time.h>
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#include <unistd.h>
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int main(int argc, char **argv)
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{
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int semid;
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struct sembuf sop;
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#ifdef HAVE_SEMTIMEDOP
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struct timespec ts;
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#endif
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if ((semid = semget(IPC_PRIVATE, 1, 0600)) < 0)
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{
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perror("semget");
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exit(1);
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}
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sop.sem_num = 0;
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sop.sem_op = 1;
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sop.sem_flg = 0;
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if (semop(semid, &sop, 1) < 0)
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{
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perror("semop");
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semctl(semid, 0, IPC_RMID);
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exit(1);
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}
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if (semctl(semid, 0, GETVAL) != 1)
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{
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perror("semctl GETVAL");
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semctl(semid, 0, IPC_RMID);
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exit(1);
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}
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if (semctl(semid, 0, GETPID) != getpid())
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{
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perror("semctl GETPID");
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semctl(semid, 0, IPC_RMID);
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exit(1);
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}
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/* The next call to semtimedop causes the program to hang on
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ppc32-linux (Yellow Dog 4.0). I don't know why. Hence the
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extended ifdef. */
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#if defined(HAVE_SEMTIMEDOP) && !defined(__powerpc__)
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sop.sem_num = 0;
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sop.sem_op = 0;
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sop.sem_flg = 0;
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ts.tv_sec = 0;
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ts.tv_nsec = 1000000;
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if (semtimedop(semid, &sop, 1, &ts) < 0 && errno != EAGAIN)
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{
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perror("semtimedop");
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semctl(semid, 0, IPC_RMID);
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exit(1);
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}
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#endif
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sop.sem_num = 0;
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sop.sem_op = -1;
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sop.sem_flg = 0;
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if (semop(semid, &sop, 1) < 0)
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{
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perror("semop");
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semctl(semid, 0, IPC_RMID);
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exit(1);
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}
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#ifdef HAVE_SEMTIMEDOP
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sop.sem_num = 0;
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sop.sem_op = 0;
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sop.sem_flg = 0;
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ts.tv_sec = 0;
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ts.tv_nsec = 1000;
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if (semtimedop(semid, &sop, 1, &ts) < 0)
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{
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perror("semtimedop");
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semctl(semid, 0, IPC_RMID);
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exit(1);
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}
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#endif
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if (semctl(semid, 0, IPC_RMID) < 0)
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{
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perror("semctl(IPC_RMID)");
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exit(1);
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}
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exit(0);
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}
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