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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
/*
* 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
FILE *sockopen(char *host, int clientPort)
{
int sock;
unsigned long inaddr;
struct sockaddr_in ad;
struct hostent *hp;
FILE *fp;
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;
}
fp = fdopen(sock, "r+");
#ifdef __SETVBUF_WORKS_OK__
/*
* For unknown reasons, this results in horrible lossage under Linux.
* To see this, condition in this line, generate a test pattern
* of 8K, fetch it, and watch it garble the test pattern.
* I think there's a bug in Linux stdio lurking here.
*/
{
static char sbuf[INTERNAL_BUFSIZE];
setvbuf(fp, sbuf, _IOLBF, INTERNAL_BUFSIZE);
}
#endif /* __SETVBUF_WORKS_OK__ */
#if !defined(__SETVBUF_WORKS_OK__) && defined(HAVE_SETLINEBUF)
/* this on the other hand works OK under Linux */
setlinebuf(fp);
#endif
return(fp);
}
#ifdef MAIN
/*
* Use the chargen service to test buffering directly.
*/
main()
{
FILE *fp = sockopen("localhost", 19);
char buf[80];
while (fgets(buf, sizeof(buf)-1, fp))
fputs(buf, stdout);
}
#endif /* MAIN */
/* socket.c ends here */
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