client.c

Linux下网络编程

#include <sys/socket.h>
#include <netdb.h>
#include <stdio.h>
#include <string.h>
#include <time.h>
#include <malloc.h>
#include <pthread.h>

#define SERVER_PORT 8080 /*端口*/
#define MAX_SIZE 5/*滑动窗口的大小*/
#define PACKET_SIZE 1400 /*每次读取的大小*/
#define FILE_SIZE 1024*1024*10+4

typedef struct packet
{
	int number; /*包的编号，编号为0表示准备发送数据，编号为-1表示数据发送完毕*/
	int length;
	/*包的数据的大小*/
	char buffer[PACKET_SIZE]; /*每次读取1024个字节*/
}packet_t;

typedef struct packet_control_block
{
	packet_t *pt;/*包的指针，每次用malloc进行产生，成功发送后释放*/
	/*int state;*//*包的状态---省略，在成功能发送就将其从Packet_State中删除即可*/
	clock_t start;/*发送的起始时间，用以判断是否超时*/
	int count; /*已被发送的次数，用以判断网络是否故障*/
}PCB_t;

typedef struct thread_parameter
{
	int i;
	FILE **fp;
	int sockfd;
	pthread_mutex_t *mutex;
	time_t start;
	struct sockaddr *addr_server;
}paras_t;

void recv_data(void *ps);

PCB_t Packet_State[MAX_SIZE] = {0}; /*构建一PCB控制块，包含5个元素，即滑动窗口的大小*/
int Wrtie_State = 0;/*当前文件的发送状态，是否发送完毕，以接受下一个请求*/
int Current_Packet = 1;


int main()
{
	int sockfd;
	if ((sockfd = socket(AF_INET, SOCK_DGRAM, 0)) == -1)
	{
		printf("socket error!!!\n");
		return 1;
	}
	struct sockaddr_in addr_server;
	addr_server.sin_family = AF_INET;
	addr_server.sin_port = htons(SERVER_PORT);
	addr_server.sin_addr.s_addr = inet_addr("10.10.32.22");

	FILE *fp = NULL;
	char buf_request[32] = {0};
	time_t start = time(NULL);
	sendto(sockfd, "GET /test", sizeof("GET /test"), 0, (struct sockaddr*)&addr_server, sizeof(struct sockaddr));

	paras_t **ps = (paras_t **)malloc(sizeof(paras_t *));
	int count = MAX_SIZE;
	pthread_mutex_t mutex;
	pthread_mutex_init(&mutex, NULL);
	int i = 0;
	for (;i < MAX_SIZE;i++)
	{
		ps[i] = (paras_t*)malloc(sizeof(paras_t));
		ps[i]->i = i;
		ps[i]->fp = &fp;
		ps[i]->start = start;
		ps[i]->mutex = &mutex;
		ps[i]->sockfd = sockfd;
		ps[i]->addr_server = (struct sockaddr*) & addr_server;
		pthread_t pt;
		pthread_create(&pt, NULL, (void *)recv_data, (void *)ps[i]);
		pthread_detach(pt);
	}
	while (1)
	{
		i = 0;
		char ch;
		memset(buf_request, '\0', 32);
		for (;(ch = getchar()) != '\n';i++)
		{
			buf_request[i] = ch;
		}
		sendto(sockfd, buf_request, strlen(buf_request), 0, (struct sockaddr*)&addr_server, sizeof(struct sockaddr));
	}
	
	for (i = 0;i < MAX_SIZE;i++)
	{
		free(ps[i]);
	}
	free(ps);
	return 0;
}


void recv_data(void *ps)
{
	int i = ((paras_t *)ps)->i;
	FILE **fp = ((paras_t *)ps)->fp;
	int sockfd = ((paras_t *)ps)->sockfd;
	pthread_mutex_t *mutex = ((paras_t *)ps)->mutex;
	time_t start = ((paras_t *)ps)->start;
	struct sockaddr addr_server = *(((paras_t *)ps)->addr_server);

	packet_t *pt = (packet_t *)malloc(sizeof(packet_t));/*每次重写入数据后不进行free*/

	while (1)
	{
		if (recvfrom(sockfd, pt, sizeof(packet_t), 0, NULL, NULL) <= 0)
		{
			printf("recvfrom error!!!\n");
			return;
		}

		if (Wrtie_State && pt->number != -1)
		{
			//pthread_mutex_lock(mutex);
			/*int offset = (pt->number - 1) * PACKET_SIZE;
			if (fseek(*fp, offset, SEEK_SET))
			{
				printf("fseek error!!!\n");
				return;
			}*/
			int length = fwrite(pt->buffer, 1, pt->length, *fp);
			//pthread_mutex_unlock(mutex);

			printf("the %d block has been received!!!", pt->number);
			printf("the length is %d!!!\n\n", length);
			char ack[16] = {0};
			sprintf(ack, "ACK %d", pt->number);
			sendto(sockfd, ack, sizeof(ack), 0, &addr_server, sizeof(struct sockaddr));

			time_t end = time(NULL);
			printf("have yongshi %d\n", (end - start));
		}
		else
		{
			if (pt->number == 0)
			{
				char buf_filename[32] = {0};
				memcpy(buf_filename, "./file_write", strlen("./file_write"));
				memcpy(buf_filename + strlen("./file_write"), "/test", sizeof("/test"));
				if ((*fp = fopen(buf_filename, "wb")) == NULL)
				{
					printf("fopen error!!!\n");
					return;
				}
				/*printf("please wait...\n");
				for (i = 0 ; i < FILE_SIZE; i++)
				{
					fwrite(&i, 4, 1, *fp);
				}*/
				Wrtie_State = 1;
			}
			else if (pt->number == -1)
			{
				fclose(*fp);
				pt = NULL;
				Wrtie_State = 0;
				break;
			}
		}
	}
	free(pt);
	pt = NULL;
}