/* like any C program, program's execution begins in main */
int
main(int argc, char* argv[])
{
int i; /* loop counter */
int thr_id1; /* thread ID for the first new thread */
int thr_id2; /* thread ID for the second new thread */
pthread_t p_thread1; /* first thread's structure */
pthread_t p_thread2; /* second thread's structure */
int num1 = 1; /* thread 1 employee number */
int num2 = 2; /* thread 2 employee number */
struct employee eotd; /* local copy of 'employee of the day'. */
struct employee* worker; /* pointer to currently checked employee */
/* initialize employee of the day to first 1. */
copy_employee(&employees[0], &employee_of_the_day);
/* create a new thread that will execute 'do_loop()' with '1' */
thr_id1 = pthread_create(&p_thread1, NULL, do_loop, (void*)&num1);
/* create a second thread that will execute 'do_loop()' with '2' */
thr_id2 = pthread_create(&p_thread2, NULL, do_loop, (void*)&num2);
/* run a loop that verifies integrity of 'employee of the day' many */
/* many many times..... */
for (i=0; i<60000; i++) {
/* save contents of 'employee of the day' to local 'worker'. */
copy_employee(&employee_of_the_day, &eotd);
worker = &employees[eotd.number-1];
/* compare employees */
if (eotd.id != worker->id) {
printf("mismatching 'id' , %d != %d (loop '%d')\n",
eotd.id, worker->id, i);
exit(0);
}
if (strcmp(eotd.first_name, worker->first_name) != 0) {
printf("mismatching 'first_name' , %s != %s (loop '%d')\n",
eotd.first_name, worker->first_name, i);
exit(0);
}
if (strcmp(eotd.last_name, worker->last_name) != 0) {
printf("mismatching 'last_name' , %s != %s (loop '%d')\n",
eotd.last_name, worker->last_name, i);
exit(0);
}
if (strcmp(eotd.department, worker->department) != 0) {
printf("mismatching 'department' , %s != %s (loop '%d')\n",
eotd.department, worker->department, i);
exit(0);
}
if (eotd.room_number != worker->room_number) {
printf("mismatching 'room_number' , %d != %d (loop '%d')\n",
eotd.room_number, worker->room_number, i);
exit(0);
}
}
printf("Glory, employees contents was always consistent\n");
return 0;
}
/* function to be executed by the variable setting threads thread */
void*
do_loop(void* data)
{
int my_num = *((int*)data); /* thread identifying number */
while (1) {
/* set employee of the day to be the one with number 'my_num'. */
copy_employee(&employees[my_num-1], &employee_of_the_day);
}
}
/* 设置本日雇员的函数 */
void*
do_loop(void* data)
{
int my_num = *((int*)data); /* 线程的雇员编号 */
while (1) {
/* 设置本日雇员为编号 my_num 的雇员 */
copy_employee(&employees[my_num-1], &employee_of_the_day);
}
}
/* 主程序，或主线程 */
int
main(int argc, char* argv[])
{
int i; /* 循环计数器 */
int ret1;
int ret2;
pthread_t p_thread1; /* 第一个线程结构 */
pthread_t p_thread2; /* 第二个线程结构 */
int num1 = 1; /* 第一个线程的雇员编号 */
int num2 = 2; /* 第二个线程的雇员编号 */
struct employee eotd; /* 本日雇员的本地拷贝 */
struct employee* worker; /* 指向正在检查的雇员 */
/* 初始化本日雇员为第一个雇员 */
copy_employee(&employees[0], &employee_of_the_day);
/* 创建一个新线程，以数据 1 执行 do_loop()，即设置 1 号雇员为本日雇员 */
ret1 = pthread_create(&p_thread1, NULL, do_loop, (void*)&num1);
/* 创建第二个新线程，以数据 2 执行 do_loop()，即设置 2 号雇员为本日雇员 */
ret2 = pthread_create(&p_thread2, NULL, do_loop, (void*)&num2);
/* 创建一个循环，检查本日雇员的数据是否一致，即是否属于同一位雇员 */
for (i=0; i<60000; i++) {
/* 保存本日雇员内容 */
copy_employee(&employee_of_the_day, &eotd);
/* 取出本日雇员的原始数据*/
worker = &employees[eotd.number-1];
/* 比较数据 */
if (eotd.id != worker->id) {
printf("mismatching 'id' , %d != %d (loop '%d')\n",
eotd.id, worker->id, i);
exit(0);
}
if (strcmp(eotd.first_name, worker->first_name) != 0) {
printf("mismatching 'first_name' , %s != %s (loop '%d')\n",
eotd.first_name, worker->first_name, i);
exit(0);
}
if (strcmp(eotd.last_name, worker->last_name) != 0) {
printf("mismatching 'last_name' , %s != %s (loop '%d')\n",
eotd.last_name, worker->last_name, i);
exit(0);
}
if (strcmp(eotd.department, worker->department) != 0) {
printf("mismatching 'department' , %s != %s (loop '%d')\n",
eotd.department, worker->department, i);
exit(0);
}
if (eotd.room_number != worker->room_number) {
printf("mismatching 'room_number' , %d != %d (loop '%d')\n",
eotd.room_number, worker->room_number, i);
exit(0);
}
}
/* 全部数据都一致 */
printf("Glory, employees contents was always consistent\n");
return 0;
}