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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>
#ifdef HAVE_MEMORY_H
#include <memory.h>
#endif /* HAVE_MEMORY_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 INET_ATON
#ifndef INADDR_NONE
#ifdef INADDR_BROADCAST
#define INADDR_NONE INADDR_BROADCAST
#else
#define INADDR_NONE -1
#endif
#endif
#endif /* INET_ATON */
int SockOpen(const char *host, int clientPort)
{
int sock;
#ifndef INET_ATON
unsigned long inaddr;
#endif /* INET_ATON */
struct sockaddr_in ad;
struct hostent *hp;
memset(&ad, 0, sizeof(ad));
ad.sin_family = AF_INET;
/* we'll accept a quad address */
#ifndef INET_ATON
inaddr = inet_addr(host);
if (inaddr != INADDR_NONE)
memcpy(&ad.sin_addr, &inaddr, sizeof(inaddr));
else
#else
if (!inet_aton(host, &ad.sin_addr))
#endif /* INET_ATON */
{
hp = gethostbyname(host);
/*
* Add a check to make sure the address has a valid IPv4 or IPv6
* length. This prevents buffer spamming by a broken DNS.
*/
if (hp == NULL || (hp->h_length != 4 && hp->h_length != 8))
return -1;
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 -1;
if (connect(sock, (struct sockaddr *) &ad, sizeof(ad)) < 0)
{
close(sock);
return -1;
}
return(sock);
}
#if defined(HAVE_STDARG_H)
int SockPrintf(int sock, char* format, ...)
{
#else
int SockPrintf(sock,format,va_alist)
int sock;
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
#ifdef HAVE_VSNPRINTF
vsnprintf(buf, sizeof(buf), format, ap);
#else
vsprintf(buf, format, ap);
#endif
va_end(ap);
return SockWrite(sock, buf, strlen(buf));
}
int SockWrite(int sock, char *buf, int len)
{
int n, wrlen = 0;
while (len)
{
n = write(sock, buf, len);
if (n <= 0)
return -1;
len -= n;
wrlen += n;
buf += n;
}
return wrlen;
}
int SockRead(int sock, char *buf, int len)
{
char *newline, *bp = buf;
int n;
if (--len < 1)
return(-1);
do {
/*
* The reason for these gymnastics is that we want two things:
* (1) to read \n-terminated lines,
* (2) to return the true length of data read, even if the
* data coming in has embedded NULS.
*/
if ((n = recv(sock, bp, len, MSG_PEEK)) <= 0)
return(-1);
if ((newline = memchr(bp, '\n', n)) != NULL)
n = newline - bp + 1;
if ((n = read(sock, bp, n)) == -1)
return(-1);
bp += n;
len -= n;
} while
(!newline && len);
*bp = '\0';
return bp - buf;
}
int SockPeek(int sock)
/* peek at the next socket character without actually reading it */
{
int n;
char ch;
if ((n = recv(sock, &ch, 1, MSG_PEEK)) == -1)
return -1;
else
return(ch);
}
#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()
{
int sock = SockOpen("localhost", 19);
char buf[80];
while (SockRead(sock, buf, sizeof(buf)-1))
SockWrite(1, buf, strlen(buf));
}
#endif /* MAIN */
/* socket.c ends here */
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