mirror of
https://github.com/riba2534/TCP-IP-NetworkNote.git
synced 2026-02-03 18:13:22 +08:00
83 lines
2.2 KiB
C
83 lines
2.2 KiB
C
#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include <unistd.h>
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#include <arpa/inet.h>
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#include <sys/socket.h>
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#define BUF_SIZE 1024
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#define OPSZ 4
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void error_handling(char *message);
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int calculate(int opnum, int opnds[], char oprator);
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int main(int argc, char *argv[])
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{
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int serv_sock, clnt_sock;
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char opinfo[BUF_SIZE];
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int result, opnd_cnt, i;
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int recv_cnt, recv_len;
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struct sockaddr_in serv_adr, clnt_adr;
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socklen_t clnt_adr_sz;
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if (argc != 2)
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{
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printf("Usage : %s <port>\n", argv[0]);
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exit(1);
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}
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serv_sock = socket(PF_INET, SOCK_STREAM, 0);
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if (serv_sock == -1)
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error_handling("socket() error");
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memset(&serv_adr, 0, sizeof(serv_adr));
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serv_adr.sin_family = AF_INET;
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serv_adr.sin_addr.s_addr = htonl(INADDR_ANY);
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serv_adr.sin_port = htons(atoi(argv[1]));
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if (bind(serv_sock, (struct sockaddr *)&serv_adr, sizeof(serv_adr)) == -1)
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error_handling("bind() error");
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if (listen(serv_sock, 5) == -1)
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error_handling("listen() error");
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clnt_adr_sz = sizeof(clnt_adr);
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for (int i = 0; i < 5; i++)
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{
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opnd_cnt = 0;
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clnt_sock = accept(serv_sock, (struct sockaddr *)&clnt_adr, &clnt_adr_sz);
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read(clnt_sock, &opnd_cnt, 1);
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recv_len = 0;
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while ((opnd_cnt * OPSZ + 1) > recv_len)
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{
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recv_cnt = read(clnt_sock, &opinfo[recv_len], BUF_SIZE - 1);
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recv_len += recv_cnt;
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}
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result = calculate(opnd_cnt, (int *)opinfo, opinfo[recv_len - 1]);
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write(clnt_sock, (char *)&result, sizeof(result));
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close(clnt_sock);
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}
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close(serv_sock);
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return 0;
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}
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int calculate(int opnum, int opnds[], char op)
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{
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int result = opnds[0], i;
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switch (op)
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{
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case '+':
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for (i = 1; i < opnum; i++)
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result += opnds[i];
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break;
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case '-':
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for (i = 1; i < opnum; i++)
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result -= opnds[i];
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break;
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case '*':
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for (i = 1; i < opnum; i++)
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result *= opnds[i];
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break;
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}
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return result;
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}
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void error_handling(char *message)
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{
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fputs(message, stderr);
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fputc('\n', stderr);
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exit(1);
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} |