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???????????????????????????????????????gcc main.c -o main -lpthread -lrt????
1 #include <stdio.h>
2 #include <stdlib.h>
3 #include <unistd.h>
4 #include <string.h>
5 #include <errno.h>
6 #include <time.h>
7 #include <pthread.h>
8
9 typedef struct condition
10 {
11     pthread_mutex_t pmutex;
12     pthread_cond_t pcond;
13 }condition_t;
14
15 typedef struct task
16 {
17     void *(*run)(void *arg);
18     void *arg;
19     struct task *next;
20 }task_t;
21
22 typedef struct threadpool
23 {
24     condition_t ready;
25     task_t *first;
26     task_t *last;
27     int counter;
28     int idle;
29     int max_threads;
30     int quit;
31 }threadpool_t;
32
33
34 int condition_init(condition_t *cond)
35 {
36     int status;
37     if((status = pthread_mutex_init(&cond->pmutex??NULL)))//????0???????????
38         return status;
39     if((status = pthread_cond_init(&cond->pcond??NULL)))
40         return status;
41     return 0;
42 }
43 int condition_lock(condition_t *cond)
44 {
45     return pthread_mutex_lock(&cond -> pmutex);
46 }
47 int condition_unlock(condition_t *cond)
48 {
49     return pthread_mutex_unlock(&cond -> pmutex);
50 }
51 int condition_wait(condition_t *cond)
52 {
53     return pthread_cond_wait(&cond -> pcond??&cond -> pmutex);
54 }
55 int condition_timewait(condition_t *cond??const struct timespec *abstime)
56 {
57     return pthread_cond_timedwait(&cond->pcond??&cond->pmutex??abstime);
58 }
59 int condition_signal(condition_t *cond)
60 {
61     return pthread_cond_signal(&cond->pcond);
62 }
63 int condition_broadcast(condition_t *cond)
64 {
65     return pthread_cond_broadcast(&cond -> pcond);
66 }
67 int condition_destory(condition_t *cond)
68 {
69     int status;
70     if((status = pthread_mutex_destroy(&cond -> pmutex)))
71         return status;
72     if((status = pthread_cond_destroy(&cond -> pcond)))
73         return status;
74     return 0;
75 }
76
77
78 void *thread_routine(void *arg)
79 {
80     struct timespec abstime;
81     int timeout;
82     printf("thread 0x%0x is starting "??(int)pthread_self());
83     threadpool_t *pool = (threadpool_t *)arg;
84     while(1)
85     {
86         timeout = 0;
87         condition_lock(&pool -> ready);
88         pool -> idle++;
89         //??????????????????????????????
90         while(pool -> first == NULL && !pool -> quit)
91         {
92             printf("thread 0x%0x is waiting "??(int)pthread_self());
93             clock_gettime(CLOCK_REALTIME??&abstime);
94             abstime.tv_sec += 2;
95             int status=condition_timewait(&pool -> ready??&abstime);
96             if(status == ETIMEDOUT)
97             {
98                 printf("thread 0x%0x is wait timed out "??(int)pthread_self());
99                 timeout = 1;
100                 break;
101             }
102
103         }
104         //????????????????????
105         pool -> idle--;
106
107         if(pool -> first != NULL)
108         {
109             task_t *t = pool -> first;
110             pool -> first = t -> next;
111             //????????????????????????????????????????????????
112             condition_unlock(&pool -> ready);
113             t -> run(t->arg);
114             free(t);
115             condition_lock(&pool -> ready);
116         }
117         //??????????????
118         if(pool -> quit && pool ->first == NULL)
119         {
120             pool -> counter--;
121             if(pool->counter == 0)
122             {
123                 condition_signal(&pool -> ready);
124             }
125             condition_unlock(&pool->ready);
126             //????????????y???
127             break;
128         }
129
130         if(timeout &&pool -> first ==NULL)
131         {
132             pool -> counter--;
133             condition_unlock(&pool->ready);
134             //????????????y???
135             break;
136         }
137         condition_unlock(&pool -> ready);
138     }
139
140     printf("thread 0x%0x is exiting "??(int)pthread_self());
141     return NULL;
142 }
143
144 //?????
145 void threadpool_init(threadpool_t *pool?? int threads)
146 {
147     condition_init(&pool -> ready);
148     pool -> first = NULL;
149     pool -> last = NULL;
150     pool -> counter = 0;
151     pool -> idle = 0;
152     pool -> max_threads = threads;
153     pool -> quit = 0;
154 }
155
156 //??????
157 void threadpool_add_task(threadpool_t *pool?? void *(*run)(void *arg)??void *arg)
158 {
159     task_t *newstask = (task_t *)malloc(sizeof(task_t));
160     newstask->run = run;
161     newstask->arg = arg;
162     newstask -> next = NULL;
163
164     condition_lock(&pool -> ready);
165     //????????????????
166     if(pool -> first ==NULL)
167     {
168         pool -> first = newstask;
169     }
170     else
171         pool -> last -> next = newstask;
172     pool -> last = newstask;
173     //????е?????????????????
174     if(pool -> idle > 0)
175     {
176         condition_signal(&pool -> ready);
177     }
178     else if(pool -> counter < pool -> max_threads)
179     {
180         pthread_t tid;
181         pthread_create(&tid??NULL??thread_routine??pool);
182         pool -> counter++;
183     }
184     condition_unlock(&pool -> ready);
185 }
186 //????????
187 void  threadpool_destory(threadpool_t *pool)
188 {
189
190     if(pool -> quit)
191     {
192         return;
193     }
194     condition_lock(&pool -> ready);
195     pool->quit = 1;
196     if(pool -> counter > 0)
197     {
198         if(pool -> idle > 0)
199             condition_broadcast(&pool->ready);
200
201         while(pool -> counter > 0)
202         {
203             condition_wait(&pool->ready);
204         }
205     }
206     condition_unlock(&pool->ready);
207     condition_destory(&pool -> ready);
208 }
209
210
211 void *mytask(void *arg)
212 {
213     printf("thread 0x%0x is working on task %d "??(int)pthread_self()??*(int*)arg);
214     sleep(1);
215     free(arg);
216     return NULL;
217 }
218 int main()
219 {
220     threadpool_t pool;
221     threadpool_init(&pool??3);
222
223     int i ;
224     for(i = 0; i < 10; i++)
225     {
226         int *arg = (int *)malloc(sizeof(int));
227         *arg = i;
228         threadpool_add_task(&pool??mytask??arg);
229     }
230
231     sleep(15);//??????????????? ???????????pthread_join????
232     threadpool_destory(&pool);
233     return 0;
234 }