【操作系统 实验十】----串行查找和并行查找（生产者消费者问题变形）

• • 1. 串行查找 job10/sfind.c
    • 题目
    • 测试
    • 代码
  • 2. 并行查找 job10/pfind.c
    • 题目
    • 测试
    • 代码

程序 sfind 在文件或者目录中查找指定的字符串，并打印包含该字符串的行，示例如下：

1. 在文件 file.c 中查找字符串 main

• 找到包含字符串 main 的行
• 打印文件名和该行

1. 在目录 test 中查找字符串 main

• 假设目录 test 下存在文件
  test/hello/hello.c
  test/world/world.c

• 对目录 test下的所有文件进行查找

• 找到包含字符串 main 的行 打印文件名和该行

cp sfind.c file.c
cp sfind.c test/world/world.c
cp sfind.c test/hello/hello.c

#include 
#include 
#include 
#include 
#include 
#include 

void find_file(char *path,char *target)
{
	FILE *file = fopen(path,"r");

	char line[256];
	while (fgets(line,sizeof(line),file)){
		if(strstr(line,target))
			printf("%s: %s",path,line);
	}

	fclose(file);
}

void find_dir(char *path,char *target)
{
	DIR *dir = opendir(path);
	struct dirent *entry;
	while(entry = readdir(dir)){
		if(strcmp(entry->d_name,".") == 0)
			continue;
		if(strcmp(entry->d_name,"..") == 0)
			continue;
		if(entry->d_type == DT_DIR)
		{
			//printf("dir %sn",entry->d_name);
			char base[80];
			memset(base,'',sizeof(base));
			strcpy(base,path);
			strcat(base,"/");	
			strcat(base,entry->d_name);
			//printf("base %sn",base);
			find_dir(base,target);		


		}
		if(entry->d_type == DT_REG)
		{
			//printf("file %sn",entry->d_name);
			char base[80];
			memset(base,'',sizeof(base));
			strcpy(base,path);
			strcat(base,"/");
			strcat(base,entry->d_name);
			find_file(base,target);
		}
	}
	closedir(dir);
}

int main(int argc,char *argv[])
{
	if(argc!=3)
	{
		puts("usage: sfind file string");
		return 0;
	}
	char *path = argv[1];
	char *string = argv[2];

	struct stat info;
	stat(path,&info);

	if(S_ISDIR(info.st_mode))
		find_dir(path,string);
	else
		find_file(path,string);
	return 0;
}

功能

• 功能与 sfind 相同
• 要求使用多线程完成

1. 主线程创建若干个子线程
   主线程负责遍历目录中的文件
   遍历到目录中的叶子节点时
   将叶子节点发送给子线程进行处理
2. 两者之间使用生产者消费者模型通信
   主线程生成数据
   子线程读取数据
   

#include
#include
#include
#include
#include
#include
#include


#define WORKER_NUMBER 4
#define CAPACITY 40


struct task{
	int is_end;
	char path[128];
	char string[128];
};

struct task buffer[100];


int in=0;
int out=0;
int buffer_is_empty()
{
	return in == out;
}
int buffer_is_full()
{
	return (in + 1)%CAPACITY == out;
}

pthread_mutex_t mutex;
pthread_cond_t wait_empty_buffer;
pthread_cond_t wait_full_buffer;


struct task get_item()
{
	struct task item;
	pthread_mutex_lock(&mutex);
	while(buffer_is_empty())
	{
		printf("wait_fulln");
		pthread_cond_wait(&wait_full_buffer,&mutex);
	}
	item = buffer[out];
	out = (out+1)% CAPACITY;
	pthread_cond_signal(&wait_empty_buffer);
	pthread_mutex_unlock(&mutex);
	return item;
}

void put_item(struct task item)
{
	pthread_mutex_lock(&mutex);
	while(buffer_is_full())
	{
		pthread_cond_wait(&wait_empty_buffer,&mutex);
	}
	buffer[in]=item;
	in = (in+1)%CAPACITY;
	pthread_cond_signal(&wait_full_buffer);
	pthread_mutex_unlock(&mutex);
}

void find_file(char *path,char *target)
{
	FILE *file = fopen(path,"r");

	char line[256];
	while (fgets(line,sizeof(line),file)){
		if(strstr(line,target))
			printf("%s: %s",path,line);
	}

	fclose(file);
}

void *worker_entry(void *arg)
{
	while(1){
		struct task task;
//		printf("in=%d,out=%dn",in,out);
		task=get_item();
		if(task.is_end)
		{	
//			printf("in = %d,out = %dn",in,out);
			struct task tm;
			tm.is_end=1;
			put_item(tm);
			break;
		}
		find_file(task.path,task.string);
	}
}

void find_dir(char *path,char *target)
{
	DIR *dir = opendir(path);
	struct dirent *entry;
	struct task buffer;
	while(entry = readdir(dir)){
		if(strcmp(entry->d_name,".") == 0)
			continue;
		if(strcmp(entry->d_name,"..") == 0)
			continue;
		if(entry->d_type == DT_DIR)
		{
			char base[80];
			memset(base,'',sizeof(base));
			strcpy(base,path);
			strcat(base,"/");	
			strcat(base,entry->d_name);
//			printf("base:%sn",base);
			find_dir(base,target);		
			
		}
		if(entry->d_type == DT_REG)
		{
			char base[80];
			memset(base,'',sizeof(base));
			strcpy(base,path);
			strcat(base,"/");
			strcat(base,entry->d_name);
			//join array
//			printf("file:%sn",base);
			buffer.is_end=0;
			strcpy(buffer.path,base);
			strcpy(buffer.string,target);
			put_item(buffer);
//			printf("put_itemn");
			break;
		}
	}
	closedir(dir);

}

int isfile(char *path)
{
	struct stat buf;
	int result;
	result = stat(path,&buf);
	if(S_IFDIR & buf.st_mode){
		return 0;
	}else if(S_IFREG & buf.st_mode){
		return 1;
	}
	return -1;
}
int main(int argc,char *argv[])
{
	char *path = argv[1];
	char *string = argv[2];

	if(isfile(path))
	{
		find_file(path,string);
		return 0;
	}
	pthread_t consumer_tid[WORKER_NUMBER];
//	printf("llln");
	find_dir(path,string);
//	printf("hhhn");
	struct task buf;
	buf.is_end=1;
	put_item(buf);
	
	//create
	for(int i=0;i