lede/package/network/services/shellsync/src/shellsync.c
2018-09-07 12:50:10 +08:00

107 lines
2.6 KiB
C

/*************************************************************************
> File Name: shellsync.c
> Author: GuoGuo
> Mail: gch981213@gmail.com
> Created Time: 2014年11月06日 星期四 19时15分30秒
************************************************************************/
#include<stdio.h>
#include<semaphore.h>
#include<fcntl.h>
#include<stdlib.h>
#include<time.h>
#include<errno.h>
#define SEM_BLOCK_NAME "SYNCSHELL_block"
#define SEM_COUNT_NAME "SYNCSHELL_count"
int wait_timeout;
int sync_wait(int nproc)
{
int flags;
int value;
sem_t *block;
sem_t *count;
struct timespec ts;
if (nproc <= 1) {
printf("sync_wait: number of processes should be larger than 1\n");
return -1;
}
if (clock_gettime(CLOCK_REALTIME, &ts) == -1) {
printf("clock_gettime error\n");
return -1;
}
ts.tv_sec += wait_timeout;
flags = O_RDWR | O_CREAT;
block = sem_open(SEM_BLOCK_NAME, flags, 0644, 0);
count = sem_open(SEM_COUNT_NAME, flags, 0644, 0);
if (block == SEM_FAILED || count == SEM_FAILED) {
printf("sync_wait: sem_open failed\n");
return -1;
}
if (sem_post(count) < 0) {
printf("sync_wait: sem_post failed\n");
return -1;
}
if (sem_getvalue(count, &value) < 0) {
printf("sync_wait: sem_getvalue failed\n");
return -1;
}
printf("%d processes have arrived, waiting for the left %d\n", value, nproc-value);
if (value >= nproc) {
while (nproc-1 > 0) {
if (sem_post(block) < 0) {
printf("sync_wait: sem_post failed\n");
return -1;
}
nproc--;
}
} else {
if (sem_timedwait(block, &ts) < 0) {
if (errno == ETIMEDOUT) {
printf("sync_wait: sem_timewait time out\n");
} else {
printf("sync_wait: sem_timewait error\n");
}
return -1;
}
}
sem_close(count);
sem_close(block);
sem_unlink(SEM_COUNT_NAME);
sem_unlink(SEM_BLOCK_NAME);
return 0;
}
int main(int argc,char *argv[])
{
if(argc!=3)
{
printf("Usage: shellsync <process num> <wait_timeout>\n");
}
else
{
int proc_num;
sscanf(argv[1],"%d",&proc_num);
sscanf(argv[2],"%d",&wait_timeout);
if(sync_wait(proc_num)<0)
{
printf("Processes sync failed.\n");
sem_unlink(SEM_COUNT_NAME);
sem_unlink(SEM_BLOCK_NAME);
return 1;
}
else
{
printf("Processes sync succeed.\n");
return 0;
}
}
}