98 lines
3.1 KiB
C
98 lines
3.1 KiB
C
#include <stdio.h>
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#include <time.h>
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#include <pthread.h>
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#include <unistd.h> // For sysconf
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// 随机数更新函数 (与原版相同)
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void GenerateRandomNumber(unsigned int *rand1_h, unsigned int *rand1_l) {
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unsigned long long x = (unsigned long long)*rand1_h;
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x *= 0x6AC690C5;
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x += *rand1_l;
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*rand1_h = (unsigned int)x;
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*rand1_l = (unsigned int)(x >> 32);
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}
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// 定义传递给线程的参数结构体
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typedef struct {
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unsigned int start;
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unsigned int end;
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unsigned int search_val;
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} ThreadArgs;
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// 全局互斥锁，只用于保护printf函数，防止输出混乱
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pthread_mutex_t printf_mutex = PTHREAD_MUTEX_INITIALIZER;
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// 线程执行的函数
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void* search_worker(void* args) {
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ThreadArgs* t_args = (ThreadArgs*)args;
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unsigned int begin_h = t_args->end;
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unsigned int begin_l = t_args->start;
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unsigned int search_val = t_args->search_val;
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// *** 核心改动：不再提前退出，每个线程必须完成自己的任务 ***
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for (unsigned int i = begin_l; i < begin_h; ++i) {
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unsigned int h = i;
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unsigned int l = 0x29A;
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GenerateRandomNumber(&h, &l);
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GenerateRandomNumber(&h, &l);
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if (l == search_val) {
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// 找到结果，锁住互斥锁以安全地打印
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pthread_mutex_lock(&printf_mutex);
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printf("找到啦~! 密码是 %08X (由线程 %lu 找到)\n", i, pthread_self());
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pthread_mutex_unlock(&printf_mutex);
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// *** 核心改动：不再退出，继续搜索本线程范围内的其他可能解 ***
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}
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}
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pthread_exit(NULL);
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}
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int main() {
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time_t begin_time, end_time;
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const unsigned int search_val = 0x39A6FFBB;
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// 注意：原程序的循环条件是 i < 0xFFFFFFFF，所以它本身不会测试 0xFFFFFFFF
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// 为了保持行为一致，我们将总范围设为 0xFFFFFFFF
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const unsigned long long total_range_end = 0xFFFFFFFF;
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long num_threads = sysconf(_SC_NPROCESSORS_ONLN);
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if (num_threads <= 0) {
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num_threads = 4; // 默认值
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}
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printf("这是一个修正后的Pthreads并行搜索程序，将使用 %ld 个线程。\n", num_threads);
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begin_time = time(NULL);
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pthread_t threads[num_threads];
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ThreadArgs thread_args[num_threads];
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// 注意数据类型，防止溢出
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unsigned long long chunk_size = total_range_end / num_threads;
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for (long i = 0; i < num_threads; ++i) {
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thread_args[i].start = i * chunk_size;
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// 最后一个线程负责处理余下的所有范围
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thread_args[i].end = (i == num_threads - 1) ? total_range_end : (i + 1) * chunk_size;
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thread_args[i].search_val = search_val;
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if (pthread_create(&threads[i], NULL, search_worker, &thread_args[i]) != 0) {
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perror("Failed to create thread");
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return 1;
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}
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}
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// 等待所有线程完成
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for (long i = 0; i < num_threads; ++i) {
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if (pthread_join(threads[i], NULL) != 0) {
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perror("Failed to join thread");
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return 2;
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}
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}
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end_time = time(NULL);
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printf("耗时 %ld 秒~~\n", end_time - begin_time);
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return 0;
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}
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