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#include <sys/time.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "../common/log.h"
#include "../common/utils.h"
#include "smtpap.h"
#include "io.h"
/* connection timeout */
extern struct timeval *conn_toutp;
/* printf-like function used to send messages to a socket */
int sendmessage(int s, char *buf, size_t buflen, const char *format, ...)
{
int retval = 0;
va_list ap;
if (!buf)
return -1;
va_start(ap,format);
retval = vsnprintf(buf,buflen, format, ap);
va_end(ap);
if (retval < 0)
{
log(LOG_DEBUG,"sendmessage() : could not print to buffer");
return -1;
}
log(LOG_DEBUG,"sendmessage() : printed this to buffer : %s",buf);
retval = write_tout(s,buf,(size_t)retval, conn_toutp);
if (retval < 0)
{
log(LOG_DEBUG,"sendmessage() : could not send");
return -1;
}
return retval;
}
/* receive a response from the recipient SMTP server into *op_in
* Can handle multi-line responses. */
int receive(int s, char **inbuf,size_t *inbuflen, int flags)
{
int inputlen = 0; /* running total length of the input */
int inputerror = 0; /* has an error occured? */
int retval = 0; /* used for saving function return values */
/* for processing multi-line responses */
int i=0;
/* storing old values of *inbuf and *inbuflen */
char *inbuf_old = NULL;
size_t inbuflen_old=0;
if ((!inbuf) || (!*inbuf) || (!inbuflen))
return -1;
/* saving old values in case we need to restore them */
inbuf_old = *inbuf;
inbuflen_old = *inbuflen;
do
{
if (inputlen == *inbuflen-1) /* we need to increase the buffer size */
{
/* increase the size of the buffer */
*inbuflen += 512;
*inbuf = (char *)realloc(*inbuf,(size_t)*inbuflen);
if (!*inbuf)
{
log(LOG_ERR,"Could not allocate memory.");
*inbuf = inbuf_old;
*inbuflen = inbuflen_old;
inputerror = 1;
break;
}
}
retval=read_tout(s,*inbuf+inputlen,(size_t)(*inbuflen-inputlen-1),flags, conn_toutp); /* subtract 1 from inbuflen to leave space for \0 */
if (retval <= 0)
{
log(LOG_ERR,"Error occured while receiving data.");
inputerror = 1;
break;
}
else
{
inputerror = 0;
inputlen += retval;
/* exit clause if we have received CRLF, otherwise we need to keep reading*/
/* also keep on reading if it's a multi-line response */
if (inputlen >= SMTPAP_CRLF_LEN)
{
if (!strncmp(*inbuf+inputlen-SMTPAP_CRLF_LEN,SMTPAP_CRLF,SMTPAP_CRLF_LEN)) /* entire line received */
{
/* now check wether we should expect more lines */
/* find the <CRLF> sequence which occurs one before last */
for(i=inputlen-SMTPAP_CRLF_LEN-1; i > 0; i--) /* move backwards, start just before the final CRLF */
{
if ((*inbuf)[i] == SMTPAP_LF) /* got a LF */
{
/* check for a CR preceding it */
if ((*inbuf)[i-1] == SMTPAP_CR) /* got a CR */
break;
}
}
if (i==0) /* correct the offset if no CRLF found */
i=-1;
/* check the 4th character after the <CRLF> to see if it is - or <SP> */
if ((*inbuf)[i+4] != '-') /* no more lines */
break;
}
}
}
} while(1);
if (!inputerror)
{
(*inbuf)[inputlen]=0; /* add the terminating NULL character */
return inputlen;
}
return -1;
}
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