/* * socket.c -- socket library functions * * For license terms, see the file COPYING in this directory. */ #include #include #include #include #include #include #include #include #if defined(STDC_HEADERS) #include #endif #if defined(HAVE_UNISTD_H) #include #endif #if defined(HAVE_STDARG_H) #include #else #include #endif #include "socket.h" #ifndef INADDR_NONE #ifdef INADDR_BROADCAST #define INADDR_NONE INADDR_BROADCAST #else #define INADDR_NONE -1 #endif #endif /* * There are, in effect, two different implementations here. One * uses read(2) and write(2) directly with no buffering, the other * uses stdio with line buffering (for better throughput). Both * are known to work under Linux. */ /* #define USE_STDIO */ #ifdef USE_STDIO /* * Size of buffer for internal buffering read function * don't increase beyond the maximum atomic read/write size for * your sockets, or you'll take a potentially huge performance hit */ #define INTERNAL_BUFSIZE 2048 #endif /* USE_STDIO */ FILE *SockOpen(char *host, int clientPort) { int sock; unsigned long inaddr; struct sockaddr_in ad; struct hostent *hp; #ifdef USE_STDIO FILE *fp; #endif /* USE_STDIO */ memset(&ad, 0, sizeof(ad)); ad.sin_family = AF_INET; inaddr = inet_addr(host); if (inaddr != INADDR_NONE) memcpy(&ad.sin_addr, &inaddr, sizeof(inaddr)); else { hp = gethostbyname(host); if (hp == NULL) return (FILE *)NULL; memcpy(&ad.sin_addr, hp->h_addr, hp->h_length); } ad.sin_port = htons(clientPort); sock = socket(AF_INET, SOCK_STREAM, 0); if (sock < 0) return (FILE *)NULL; if (connect(sock, (struct sockaddr *) &ad, sizeof(ad)) < 0) { close(sock); return (FILE *)NULL; } #ifndef USE_STDIO return fdopen(sock, "r+"); #else fp = fdopen(sock, "r+"); setvbuf(fp, NULL, _IOLBF, INTERNAL_BUFSIZE); return(fp); #endif /* USE_STDIO */ } #if defined(HAVE_STDARG_H) int SockPrintf(FILE *sockfp, char* format, ...) { #else int SockPrintf(sockfp,format,va_alist) FILE *sockfp; char *format; va_dcl { #endif va_list ap; char buf[8192]; #if defined(HAVE_STDARG_H) va_start(ap, format) ; #else va_start(ap); #endif vsprintf(buf, format, ap); va_end(ap); return SockWrite(buf, 1, strlen(buf), sockfp); } #ifndef USE_STDIO int SockWrite(char *buf, int size, int len, FILE *sockfp) { int n, wrlen = 0; len *= size; while (len) { n = write(fileno(sockfp), buf, len); if (n <= 0) return -1; len -= n; wrlen += n; buf += n; } return wrlen; } char *SockGets(char *buf, int len, FILE *sockfp) { int rdlen = 0; char *cp = buf; while (--len) { if (read(fileno(sockfp), cp, 1) != 1) return((char *)NULL); else rdlen++; if (*cp++ == '\n') break; } *cp = 0; return buf; } #else int SockWrite(char *buf, int size, int len, FILE *sockfp) { return(fwrite(buf, size, len, sockfp)); } char *SockGets(char *buf, int len, FILE *sockfp) { return(fgets(buf, len, sockfp)); } #endif #ifdef MAIN /* * Use the chargen service to test buffering directly. */ main() { FILE *fp = SockOpen("localhost", 19); char buf[80]; while (SockGets(buf, sizeof(buf)-1, fp)) SockWrite(buf, 1, strlen(buf), stdout); } #endif /* MAIN */ /* socket.c ends here */