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/*
* socket.c -- socket library functions
*
* For license terms, see the file COPYING in this directory.
*/
#include <config.h>
#include <stdio.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>
#if defined(STDC_HEADERS)
#include <stdlib.h>
#endif
#if defined(HAVE_UNISTD_H)
#include <unistd.h>
#endif
#if defined(HAVE_STDARG_H)
#include <stdarg.h>
#else
#include <varargs.h>
#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. You get the former by configuring
* with --disable-stdio, the latter by configuring with --enable-stdio
* or by default.
*/
#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)
{
int n = fwrite(buf, size, len, sockfp);
fseek(sockfp, 0L, SEEK_CUR); /* required by POSIX */
return(n);
}
char *SockGets(char *buf, int len, FILE *sockfp)
{
char *in = fgets(buf, len, sockfp);
#ifndef linux
/*
* Weirdly, this actually wedges under Linux (2.0.27 with libc 5.3.12-8).
* It's apparently good under NEXTSTEP.
*/
fseek(sockfp, 0L, SEEK_CUR); /* required by POSIX */
#endif /* linux */
return(in);
}
#endif
#ifdef MAIN
/*
* Use the chargen service to test input beuffering directly.
* You may have to uncomment the `chargen' service description in your
* inetd.conf (and then SIGHUP inetd) for this to work.
*/
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 */
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