From: Dylan Lloyd Date: Wed, 13 Feb 2013 06:01:47 +0000 (-0500) Subject: refactored notify.c for clarity X-Git-Url: https://disinclined.org/git/?a=commitdiff_plain;ds=sidebyside;p=irssi-notify.git refactored notify.c for clarity --- diff --git a/listen.c b/listen.c index fd7ce87..79cff94 100644 --- a/listen.c +++ b/listen.c @@ -21,12 +21,13 @@ void sigchld_handler(int s) while(waitpid(-1, NULL, WNOHANG) > 0); } -// look for an IPv4 host:port in an address structure +// look for an IPv4/6 host:port in an address structure void *get_in_addr(struct sockaddr *sa) { if (sa->sa_family == AF_INET) { return &(((struct sockaddr_in*)sa)->sin_addr); } + return &(((struct sockaddr_in6*)sa)->sin6_addr); } int main(void) diff --git a/notify.c b/notify.c index 0f00e34..89e71e6 100644 --- a/notify.c +++ b/notify.c @@ -10,30 +10,28 @@ #include -#define PORT "3490" // the port client will be connecting to +#define PORT "3490" +#define MAX_MSG_ACCEPT_BYTES 100 -#define MAXDATASIZE 100 // max number of bytes we can get at once - -// get sockaddr, IPv4 or IPv6: +// look for an IPv4/6 host:port in an address structure void *get_in_addr(struct sockaddr *sa) { if (sa->sa_family == AF_INET) { return &(((struct sockaddr_in*)sa)->sin_addr); } - return &(((struct sockaddr_in6*)sa)->sin6_addr); } int main(int argc, char *argv[]) { int sockfd, numbytes; - char buf[MAXDATASIZE]; - struct addrinfo hints, *servinfo, *p; - int rv; + struct addrinfo hints, *servinfo, *port; char s[INET6_ADDRSTRLEN]; + int rv; + char buf[MAX_MSG_ACCEPT_BYTES]; if (argc != 3) { - fprintf(stderr,"usage: client hostname 'message'\n"); + fprintf(stderr, "usage: client hostname 'message'\n"); exit(1); } @@ -41,29 +39,28 @@ int main(int argc, char *argv[]) hints.ai_family = AF_UNSPEC; hints.ai_socktype = SOCK_STREAM; + // look up local address information if ((rv = getaddrinfo(argv[1], PORT, &hints, &servinfo)) != 0) { fprintf(stderr, "getaddrinfo: %s\n", gai_strerror(rv)); return 1; } - // loop through all the results and connect to the first we can - for(p = servinfo; p != NULL; p = p->ai_next) { - if ((sockfd = socket(p->ai_family, p->ai_socktype, - p->ai_protocol)) == -1) { + // loop over available interfaces and try to bind to port + for(port = servinfo; port != NULL; port = port->ai_next) { + if ((sockfd = socket(port->ai_family, port->ai_socktype, + port->ai_protocol)) == -1) { perror("client: socket"); continue; } - - if (connect(sockfd, p->ai_addr, p->ai_addrlen) == -1) { + if (connect(sockfd, port->ai_addr, port->ai_addrlen) == -1) { close(sockfd); perror("client: connect"); continue; } - break; } - if (p == NULL) { + if (port == NULL) { fprintf(stderr, "client: failed to connect\n"); return 2; }