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/* Sgets.c
*
* Syntax : Sgets(buf,maxbuf,skt)
* Returns: buf if it worked, a NULL pointer otherwise
*
* buf[maxbuf]
*/
#include <stdio.h>
#include "sockets.h"
/* ---------------------------------------------------------------------------
* Local Definitions:
*/
/* ---------------------------------------------------------------------------
* Function Declarations:
*/
/* ---------------------------------------------------------------------------
* Source Code:
*/
/* Sgets:
* Gets a null-byte terminated string from the specified Socket.
* Note that the maxbuf *must be* >= 2 (one byte needed for the
* null byte termination, and one byte for a minimal amount of data).
* This function blocks and will fill the buffer "buf" with up
* to maxbuf characters. The output from this function will
* be null byte terminated when successful, even on a full buffer condition.
*
* Returns: buf : on success
* null ptr: on failure
*/
#ifdef __PROTOTYPE__
char *Sgets(
char *buf, /* holds null-byte terminated string from Socket */
int maxbuf, /* maximum size of string allowed in buf */
Socket *skt) /* Socket from which data is to be read */
#else
char *Sgets(
buf,
maxbuf,
skt)
char *buf;
int maxbuf;
Socket *skt;
#endif
{
int buflen;
int mesglen;
char *b = NULL;
#ifndef SSLNOPEEK
char *nb = NULL;
#endif
/* error or whatever, until the buffer actually gets something its empty */
buf[0]= '\0';
/* sanity check */
if(!skt) {
return (char *) NULL;
}
#ifdef SSLNOPEEK /* stupid, so it receives one byte at a time */
for(b= buf, buflen= maxbuf-1; buflen; --buflen, ++b) {
if(recv(skt->skt,b,(unsigned) 1,0) <= 0) {
return (char *) NULL;
}
if(*b == '\0') break;
}
#else
/* receive bytes until a nullbyte is received */
buflen = maxbuf - 2; /* leave space for trailing null byte */
buf[buflen+1]= '\0'; /* so strchr will find a null byte somewhere */
for(b= buf, mesglen= 0; buflen > 0; b+= mesglen, buflen-= mesglen) {
/* block until something shows up on the Socket */
if(!Swait(skt)) { /* null == error - should be at least 1 null byte */
return (char *) NULL;
}
/* peek at contents of socket queue */
mesglen= recv(skt->skt,b,buflen,MSG_PEEK);
if(mesglen <= 0) { /* socket error - bad receive */
return (char *) NULL;
}
else if(mesglen > 0) { /* check if null byte received yet */
nb= strchr(b,'\0'); /* find null byte in buffer */
if(nb < b + mesglen) { /* null byte inside peeked-at message */
mesglen= nb - b + 1; /* read up to and including null byte */
if(Sreadbytes(skt,b,mesglen) <= 0) {
return buf;
}
break;
}
else if(mesglen >= buflen) { /* whoops - full buffer */
if(Sreadbytes(skt,b,buflen) <= 0) {
return buf;
}
b[buflen]= '\0'; /* end-of-buffer termination */
break;
}
else if(Sreadbytes(skt,b,mesglen) <= 0) { /* partial read */
return buf;
}
}
}
#endif /* #ifdef SSLNOPEEK ... #else ... #endif */
/* return message */
return buf;
}
/* ---------------------------------------------------------------------
* vim: ts=4
*/
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