ref: 13524eb51bcdd4ee9316a00b8ad6c1e6ee490ab6
dir: /llt/socket.c/
#include <stdlib.h> #include <stdio.h> #include <string.h> #include <unistd.h> #include <assert.h> #include <errno.h> #include <sys/time.h> #include <sys/select.h> #include <sys/types.h> #include "dtypes.h" #include "socket.h" int mysocket(int domain, int type, int protocol) { int val; int s = socket(domain, type, protocol); if (s < 0) return s; val = 4096; setsockopt(s, SOL_SOCKET, SO_RCVBUF, (char*)&val, sizeof(int)); val = 4096; setsockopt(s, SOL_SOCKET, SO_SNDBUF, (char*)&val, sizeof(int)); return s; } void set_nonblock(int socket, int yes) { int flags; flags = fcntl(socket,F_GETFL,0); assert(flags != -1); if (yes) fcntl(socket, F_SETFL, flags | O_NONBLOCK); else fcntl(socket, F_SETFL, flags & ~O_NONBLOCK); } /* returns a socket on which to accept() connections */ int open_tcp_port(short portno) { int sockfd; struct sockaddr_in serv_addr; sockfd = mysocket(PF_INET, SOCK_STREAM, IPPROTO_TCP); if (sockfd < 0) return -1; bzero(&serv_addr, sizeof(serv_addr)); serv_addr.sin_family = AF_INET; serv_addr.sin_addr.s_addr = htonl(INADDR_ANY); serv_addr.sin_port = htons(portno); if (bind(sockfd, (struct sockaddr*)&serv_addr, sizeof(serv_addr)) < 0) { return -1; } listen(sockfd, 4); return sockfd; } /* returns a socket on which to accept() connections, finding some available port (portno is value-return) */ int open_any_tcp_port(short *portno) { int sockfd; struct sockaddr_in serv_addr; sockfd = mysocket(PF_INET, SOCK_STREAM, IPPROTO_TCP); if (sockfd < 0) return -1; bzero(&serv_addr, sizeof(serv_addr)); serv_addr.sin_family = AF_INET; serv_addr.sin_addr.s_addr = htonl(INADDR_ANY); serv_addr.sin_port = htons(*portno); while (bind(sockfd, (struct sockaddr*)&serv_addr, sizeof(serv_addr)) < 0) { (*portno)++; serv_addr.sin_port = htons(*portno); } listen(sockfd, 4); return sockfd; } /* returns a socket on which to accept() connections, finding some available port (portno is value-return) */ int open_any_udp_port(short *portno) { int sockfd; struct sockaddr_in serv_addr; sockfd = mysocket(PF_INET, SOCK_DGRAM, 0); if (sockfd < 0) return -1; bzero(&serv_addr, sizeof(serv_addr)); serv_addr.sin_family = AF_INET; serv_addr.sin_addr.s_addr = htonl(INADDR_ANY); serv_addr.sin_port = htons(*portno); while (bind(sockfd, (struct sockaddr*)&serv_addr, sizeof(serv_addr)) < 0) { (*portno)++; serv_addr.sin_port = htons(*portno); } return sockfd; } void closesocket(int fd) { close(fd); } /* returns a socket to use to send data to the given address */ int connect_to_host(char *hostname, short portno) { struct hostent *host_info; int sockfd, yes=1; struct sockaddr_in host_addr; host_info = gethostbyname(hostname); if (host_info == NULL) { return -1; } sockfd = mysocket(AF_INET, SOCK_STREAM, IPPROTO_TCP); if (sockfd < 0) { return -1; } (void)setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof(int)); memset((char*)&host_addr, 0, sizeof(host_addr)); host_addr.sin_family = host_info->h_addrtype; memcpy((char*)&host_addr.sin_addr, host_info->h_addr, host_info->h_length); host_addr.sin_port = htons(portno); if (connect(sockfd, (struct sockaddr*)&host_addr, sizeof(struct sockaddr_in)) != 0) { closesocket(sockfd); return -1; } return sockfd; } int connect_to_addr(struct sockaddr_in *host_addr) { int sockfd, yes=1; sockfd = mysocket(AF_INET, SOCK_STREAM, IPPROTO_TCP); if (sockfd < 0) { return -1; } (void)setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof(int)); if (connect(sockfd, (struct sockaddr*)host_addr, sizeof(struct sockaddr_in)) != 0) { closesocket(sockfd); return -1; } return sockfd; } /* repeated send until all of buffer is sent */ int sendall(int sockfd, char *buffer, int bufLen, int flags) { int numBytesToSend=bufLen, length; while (numBytesToSend>0) { length = send(sockfd, (void *) buffer, numBytesToSend, flags); if (length < 0) { return(-1); } numBytesToSend -= length ; buffer += length ; } return(bufLen); } /* repeated read until all of buffer is read */ int readall(int sockfd, char *buffer, int bufLen, int flags) { int numBytesToRead=bufLen, length; while (numBytesToRead>0) { length = recv(sockfd, buffer, numBytesToRead, flags); if (length <= 0) { return(length); } numBytesToRead -= length; buffer += length; } return(bufLen); } int addr_eq(struct sockaddr_in *a, struct sockaddr_in *b) { if (a->sin_port == b->sin_port && a->sin_addr.s_addr == b->sin_addr.s_addr) return 1; return 0; } int socket_ready(int sock) { fd_set fds; struct timeval timeout; timeout.tv_sec = 0; timeout.tv_usec = 1000; FD_ZERO(&fds); FD_SET(sock, &fds); select(sock+1, &fds, NULL, NULL, &timeout); return FD_ISSET(sock, &fds); }