2020/06/09

[C] Simple state machine with pthread support 


  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
#include <stdio.h>
#include <time.h>
#include <stdlib.h>
#include <signal.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <string.h>
#include <arpa/inet.h>
#include <fcntl.h>
#include <unistd.h>
#include <pthread.h>
#include <sys/types.h>
#include <sys/ipc.h>
#include <sys/msg.h>

#if 1
#define DPRINTF(format, ...) do { \
	printf(format, ## __VA_ARGS__); \
	} while(0)
#else
#define DPRINTF(format, ...) do {} while(0)
#endif

#define SM_CONTINUE	1
#define SM_STOP		0
#define MAX_THREAD	10

enum STATE {
	ST_NULL=0,
	ST_1,
	ST_2,
	ST_MAX,
};

struct STATE_INFO {
	int threadIndex;
	enum STATE state;
	char wait;
};

struct STATE_MACHINE {
	enum STATE state;
	int (*stFunc) (struct STATE_INFO *sInfo);
};

int st1 (struct STATE_INFO *sInfo);
int st2 (struct STATE_INFO *sInfo);

struct STATE_MACHINE statemachineList[ST_MAX] = {
	{ST_1,		st1},
	{ST_2,		st2},
};

pthread_t tid[MAX_THREAD]={0};

void threadWaitReady(struct STATE_INFO *sInfo) {
	while (sInfo->wait) {
		usleep(100);
	}
}

int statemachineFindIndexByState(enum STATE state)
{
	int i, index=-1;
	int stCount = sizeof(statemachineList)/sizeof(struct STATE_MACHINE);
	
	for(i=0; i<stCount; i++) {
		if (statemachineList[i].state == state) {
			index = i;
			i = stCount;
		}
	}
	return index;
}

void * statemachineMain(void *arg)
{
	struct STATE_INFO sInfo, *ssInfo;
	int stateIndex;
	char resume=SM_CONTINUE;

	pthread_detach(pthread_self());
	memcpy(&sInfo, arg, sizeof(sInfo));
	ssInfo = arg;
	ssInfo->wait = 0;
	DPRINTF("t[%d] [%s] start statemachine with state %d\n", sInfo.threadIndex, __func__, sInfo.state);
	while (resume != SM_STOP) {
		stateIndex = statemachineFindIndexByState(sInfo.state);
		if (-1 == stateIndex) {
			resume = SM_STOP;
		} else {
			if (statemachineList[stateIndex].stFunc)
			{
				resume = statemachineList[stateIndex].stFunc(&sInfo);
			} else {
				resume = SM_STOP;
				DPRINTF("t[%d] [%s] state %d without callback function\n", sInfo.threadIndex, __func__, sInfo.state);
			}
		}
	}
	tid[sInfo.threadIndex] = 0;
	pthread_exit(NULL);
}

int threadFindFree (void)
{
	int i, retval=-1;
	for (i=0; i<MAX_THREAD; i++) {
		if (0 == tid[i]) {
			retval = i;
			break;
		}
	}
	return retval;
}

int main(int argc, char *argv[])
{
	struct STATE_INFO sInfo;
	int i, tIndex;
	
	i=0;
	while(1) {
		bzero(&sInfo, sizeof(sInfo));
		sInfo.threadIndex = threadFindFree();
		if (-1 != sInfo.threadIndex) {
			++i;
			i %= ST_MAX;
			sInfo.state = i;
			sInfo.wait = 1;
			if(pthread_create(&tid[sInfo.threadIndex], NULL, statemachineMain, (void*) &sInfo) != 0 ) {
				tid[sInfo.threadIndex] = 0;
				DPRINTF("t[%d] [%s] Failed to create thread\n", sInfo.threadIndex , __func__);
			} else {
				threadWaitReady(&sInfo);
			}
		}
		usleep(1234567);
	}
}

int st1 (struct STATE_INFO *sInfo)
{
	DPRINTF("t[%d] [%s]\n", sInfo->threadIndex, __func__);
	sInfo->state = ST_2;
	usleep(1000000);
	return SM_CONTINUE;
}

int st2 (struct STATE_INFO *sInfo)
{
	DPRINTF("t[%d] [%s]\n", sInfo->threadIndex, __func__);
	sInfo->state = ST_1;
	usleep(2000000);
	return SM_CONTINUE;
}

on 沒有留言:
標籤：
訂閱： 文章 (Atom)