dgclibcast5.lc

unix网络编程卷1：套接口API的全书源码

#include    "unp.h"##  1 ##src/bcast/dgclibcast5.c##
#include    <setjmp.h>##  2 ##src/bcast/dgclibcast5.c##

static void recvfrom_alarm(int);##  3 ##src/bcast/dgclibcast5.c##
static sigjmp_buf jmpbuf;##  4 ##src/bcast/dgclibcast5.c##

void##  5 ##src/bcast/dgclibcast5.c##
dg_cli(FILE *fp, int sockfd, const SA *pservaddr, socklen_t servlen)##  6 ##src/bcast/dgclibcast5.c##
{##  7 ##src/bcast/dgclibcast5.c##
    int     n;##  8 ##src/bcast/dgclibcast5.c##
    const int on = 1;##  9 ##src/bcast/dgclibcast5.c##
    char    sendline[MAXLINE], recvline[MAXLINE + 1];## 10 ##src/bcast/dgclibcast5.c##
    socklen_t len;## 11 ##src/bcast/dgclibcast5.c##
    struct sockaddr *preply_addr;## 12 ##src/bcast/dgclibcast5.c##

    preply_addr = Malloc(servlen);## 13 ##src/bcast/dgclibcast5.c##

    Setsockopt(sockfd, SOL_SOCKET, SO_BROADCAST, &on, sizeof(on));## 14 ##src/bcast/dgclibcast5.c##

    Signal(SIGALRM, recvfrom_alarm);## 15 ##src/bcast/dgclibcast5.c##

    while (Fgets(sendline, MAXLINE, fp) != NULL) {## 16 ##src/bcast/dgclibcast5.c##

        Sendto(sockfd, sendline, strlen(sendline), 0, pservaddr, servlen);## 17 ##src/bcast/dgclibcast5.c##

        alarm(5);## 18 ##src/bcast/dgclibcast5.c##
        for (;;) {## 19 ##src/bcast/dgclibcast5.c##
            if (sigsetjmp(jmpbuf, 1) != 0)## 20 ##src/bcast/dgclibcast5.c##
                break;## 21 ##src/bcast/dgclibcast5.c##
            len = servlen;## 22 ##src/bcast/dgclibcast5.c##
            n = Recvfrom(sockfd, recvline, MAXLINE, 0, preply_addr, &len);## 23 ##src/bcast/dgclibcast5.c##
            recvline[n] = 0;    /* null terminate */## 24 ##src/bcast/dgclibcast5.c##
            printf("from %s: %s",## 25 ##src/bcast/dgclibcast5.c##
                   Sock_ntop_host(preply_addr, len), recvline);## 26 ##src/bcast/dgclibcast5.c##
        }## 27 ##src/bcast/dgclibcast5.c##
    }## 28 ##src/bcast/dgclibcast5.c##
}## 29 ##src/bcast/dgclibcast5.c##

static void## 30 ##src/bcast/dgclibcast5.c##
recvfrom_alarm(int signo)## 31 ##src/bcast/dgclibcast5.c##
{## 32 ##src/bcast/dgclibcast5.c##
    siglongjmp(jmpbuf, 1);## 33 ##src/bcast/dgclibcast5.c##
}## 34 ##src/bcast/dgclibcast5.c##