nntp.c

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      (f = netmsg_slurp (LOCAL->nntpstream->netstream,&k,NIL))) {
    fread (LOCAL->over_fmt = (char *) fs_get ((size_t) k + 3),
	   (size_t) 1,(size_t) k,f);
    LOCAL->over_fmt[k] = '\0';
    fclose (f);			/* flush temp file */
  }
  if (nmsgs) {			/* if any messages exist */
    short silent = stream->silent;
    stream->silent = T;		/* don't notify main program yet */
    mail_exists (stream,nmsgs);	/* silently set the cache to the guesstimate */
				/* get UID/sequence map, nuke holes */
    if (nntp_getmap (stream,mbx,i,j,rnmsgs,nmsgs,tmp)) {
      for (nmsgs = 0;		/* calculate true count */
	   (s = net_getline (nstream->netstream)) && strcmp (s,"."); ) {
	if ((k = atol (s)) > j){/* discard too high article numbers */
	  sprintf (tmp,"NNTP SERVER BUG (out of range article ID): %lu > %lu",
		   k,j);
	  mm_notify (stream,tmp,NIL);
	  stream->unhealthy = T;
	}
	else if (k >= i) {	/* silently ignore too-low article numbers */
				/* guard against server returning extra msgs */
	  if (nmsgs == stream->nmsgs) mail_exists (stream,nmsgs+1);
				/* create elt for this message, set UID */
	  mail_elt (stream,++nmsgs)->private.uid = k;
	}
	fs_give ((void **) &s);
      }
      if (s) fs_give ((void **) &s);
    }
				/* assume c-client/NNTP map is entire range */
    else for (k = 1; k <= nmsgs; k++) mail_elt (stream,k)->private.uid = i++;
    stream->unhealthy = NIL;	/* set healthy */
    stream->nmsgs = 0;		/* whack it back down */
    stream->silent = silent;	/* restore old silent setting */
    mail_exists (stream,nmsgs);	/* notify upper level that messages exist */
				/* read .newsrc entries */
    mail_recent (stream,newsrc_read (mbx,stream));
  }
  else {			/* empty newsgroup or halfopen */
    if (!(stream->silent || stream->halfopen)) {
      sprintf (tmp,"Newsgroup %s is empty",mbx);
      mm_log (tmp,WARN);
    }
    mail_exists (stream,(long) 0);
    mail_recent (stream,(long) 0);
  }
  return stream;		/* return stream to caller */
}

/* NNTP close
 * Accepts: MAIL stream
 *	    option flags
 */

void nntp_mclose (MAILSTREAM *stream,long options)
{
  unsigned long i;
  MESSAGECACHE *elt;
  if (LOCAL) {			/* only if a file is open */
    nntp_check (stream);	/* dump final checkpoint */
    if (LOCAL->over_fmt) fs_give ((void **) &LOCAL->over_fmt);
    if (LOCAL->name) fs_give ((void **) &LOCAL->name);
    if (LOCAL->user) fs_give ((void **) &LOCAL->user);
    if (LOCAL->newsrc) fs_give ((void **) &LOCAL->newsrc);
    if (LOCAL->txt) fclose (LOCAL->txt);
				/* close NNTP connection */
    if (LOCAL->nntpstream) nntp_close (LOCAL->nntpstream);
    for (i = 1; i <= stream->nmsgs; i++)
      if ((elt = mail_elt (stream,i))->private.spare.ptr)
	fs_give ((void **) &elt->private.spare.ptr);
				/* nuke the local data */
    fs_give ((void **) &stream->local);
    stream->dtb = NIL;		/* log out the DTB */
  }
}

/* NNTP fetch fast information
 * Accepts: MAIL stream
 *	    sequence
 *	    option flags
 * This is ugly and slow
 */

void nntp_fetchfast (MAILSTREAM *stream,char *sequence,long flags)
{
  unsigned long i;
  MESSAGECACHE *elt;
				/* get sequence */
  if (stream && LOCAL && ((flags & FT_UID) ?
			  mail_uid_sequence (stream,sequence) :
			  mail_sequence (stream,sequence)))
    for (i = 1; i <= stream->nmsgs; i++) {
      if ((elt = mail_elt (stream,i))->sequence && (elt->valid = T) &&
	  !(elt->day && elt->rfc822_size)) {
	ENVELOPE **env = NIL;
	ENVELOPE *e = NIL;
	if (!stream->scache) env = &elt->private.msg.env;
	else if (stream->msgno == i) env = &stream->env;
	else env = &e;
	if (!*env || !elt->rfc822_size) {
	  STRING bs;
	  unsigned long hs;
	  char *ht = (*stream->dtb->header) (stream,i,&hs,NIL);
				/* need to make an envelope? */
	  if (!*env) rfc822_parse_msg (env,NIL,ht,hs,NIL,BADHOST,
				       stream->dtb->flags);
				/* need message size too, ugh */
	  if (!elt->rfc822_size) {
	    (*stream->dtb->text) (stream,i,&bs,FT_PEEK);
	    elt->rfc822_size = hs + SIZE (&bs) - GETPOS (&bs);
	  }
	}
				/* if need date, have date in envelope? */
	if (!elt->day && *env && (*env)->date)
	  mail_parse_date (elt,(*env)->date);
				/* sigh, fill in bogus default */
	if (!elt->day) elt->day = elt->month = 1;
	mail_free_envelope (&e);
      }
    }
}

/* NNTP fetch flags
 * Accepts: MAIL stream
 *	    sequence
 *	    option flags
 */

void nntp_flags (MAILSTREAM *stream,char *sequence,long flags)
{
  unsigned long i;
  if ((flags & FT_UID) ?	/* validate all elts */
      mail_uid_sequence (stream,sequence) : mail_sequence (stream,sequence))
    for (i = 1; i <= stream->nmsgs; i++) mail_elt (stream,i)->valid = T;
}

/* NNTP fetch overview
 * Accepts: MAIL stream, sequence bits set
 *	    overview return function
 * Returns: T if successful, NIL otherwise
 */

long nntp_overview (MAILSTREAM *stream,overview_t ofn)
{
  unsigned long i,j,k,uid;
  char c,*s,*t,*v,tmp[MAILTMPLEN];
  MESSAGECACHE *elt;
  OVERVIEW ov;
  if (!LOCAL->nntpstream->netstream) return NIL;
				/* scan sequence to load cache */
  for (i = 1; i <= stream->nmsgs; i++)
				/* have cached overview yet? */
    if ((elt = mail_elt (stream,i))->sequence && !elt->private.spare.ptr) {
      for (j = i + 1;		/* no, find end of cache gap range */
	   (j <= stream->nmsgs) && (elt = mail_elt (stream,j))->sequence &&
	   !elt->private.spare.ptr; j++);
				/* make NNTP range */
      sprintf (tmp,(i == (j - 1)) ? "%lu" : "%lu-%lu",mail_uid (stream,i),
	       mail_uid (stream,j - 1));
      i = j;			/* advance beyond gap */
				/* ask server for overview data to cache */
      if (nntp_over (stream,tmp)) {
	while ((s = net_getline (LOCAL->nntpstream->netstream)) &&
	       strcmp (s,".")) {
				/* death to embedded newlines */
	  for (t = v = s; c = *v++;)
	    if ((c != '\012') && (c != '\015')) *t++ = c;
	  *t++ = '\0';		/* tie off string in case it was shortened */
				/* cache the overview if found its sequence */
	  if ((uid = atol (s)) && (k = mail_msgno (stream,uid)) &&
	      (t = strchr (s,'\t'))) {
	    if ((elt = mail_elt (stream,k))->private.spare.ptr)
	      fs_give ((void **) &elt->private.spare.ptr);
	    elt->private.spare.ptr = cpystr (t + 1);
	  }
	  else {		/* shouldn't happen, snarl if it does */
	    sprintf (tmp,"Server returned data for unknown UID %lu",uid);
	    mm_notify (stream,tmp,WARN);
	    stream->unhealthy = T;
	  }
				/* flush the overview */
	  fs_give ((void **) &s);
	}
	stream->unhealthy = NIL;/* set healthy */
				/* flush the terminating dot */
	if (s) fs_give ((void **) &s);
      }
      else i = stream->nmsgs;	/* OVER failed, punt cache load */
    }

				/* now scan sequence to return overviews */
  if (ofn) for (i = 1; i <= stream->nmsgs; i++)
    if ((elt = mail_elt (stream,i))->sequence) {
      uid = mail_uid (stream,i);/* UID for this message */
				/* parse cached overview */
      if (nntp_parse_overview (&ov,s = (char *) elt->private.spare.ptr,elt))
	(*ofn) (stream,uid,&ov,i);
      else {			/* parse failed */
	(*ofn) (stream,uid,NIL,i);
	if (s && *s) {		/* unusable cached entry? */
	  sprintf (tmp,"Unable to parse overview for UID %lu: %.500s",uid,s);
	  mm_notify (stream,tmp,WARN);
	  stream->unhealthy = T;
				/* erase it from the cache */
	  fs_give ((void **) &s);
	}
	stream->unhealthy = NIL;/* set healthy */
				/* insert empty cached text as necessary */
	if (!s) elt->private.spare.ptr = cpystr ("");
      }
				/* clean up overview data */
      if (ov.from) mail_free_address (&ov.from);
      if (ov.subject) fs_give ((void **) &ov.subject);
    }
  return T;
}

/* Send OVER to NNTP server
 * Accepts: mail stream
 *	    sequence to send
 * Returns: T if success and overviews will follow, else NIL
 */

long nntp_over (MAILSTREAM *stream,char *sequence)
{
  unsigned char *s;
				/* test for Netscape Collabra server */
  if (EXTENSION.over && LOCAL->xover &&
      nntp_send (LOCAL->nntpstream,"OVER","0") == NNTPOVER) {
    /* "Netscape-Collabra/3.52 03615 NNTP" responds to the OVER command with
     * a bogus "Subject:From:Date:Bytes:Lines" response followed by overviews
     * which lack the Message-ID and References:.  This violates the draft
     * NNTP specification (draft-ietf-nntpext-base-18.txt as of this writing).
     * XOVER works fine.
     */
    while ((s = net_getline (LOCAL->nntpstream->netstream)) && strcmp (s,".")){
      if (!isdigit (*s)) {	/* is it that fetid piece of reptile dung? */
	EXTENSION.over = NIL;	/* sure smells like it */
	mm_log ("Working around Netscape Collabra bug",WARN);
      }
      fs_give ((void **) &s);	/* flush the overview */
    }
    if (s) fs_give ((void **) &s);
				/* don't do this test again */
    if (EXTENSION.over) LOCAL->xover = NIL;
  }
  if (EXTENSION.over)		/* have OVER extension? */
    return (nntp_send (LOCAL->nntpstream,"OVER",sequence) == NNTPOVER) ?
      LONGT : NIL;
  if (LOCAL->xover)		/* try the experiment extension then */
    switch ((int) nntp_send (LOCAL->nntpstream,"XOVER",sequence)) {
    case NNTPOVER:		/* got an overview? */
      return LONGT;
    case NNTPBADCMD:		/* unknown command? */
      LOCAL->xover = NIL;	/* disable future XOVER attempts */
    }
  return NIL;
}

/* Parse OVERVIEW struct from cached NNTP OVER response
 * Accepts: struct to load
 *	    cached OVER response
 *	    internaldate
 * Returns: T if success, NIL if fail
 */

long nntp_parse_overview (OVERVIEW *ov,char *text,MESSAGECACHE *elt)
{
  char *t;
				/* nothing in overview yet */
  memset ((void *) ov,0,sizeof (OVERVIEW));
				/* no cached data */
  if (!(text && *text)) return NIL;
  ov->subject = cpystr (text);	/* make hackable copy of overview */
				/* find end of Subject */
  if (t = strchr (ov->subject,'\t')) {
    *t++ = '\0';		/* tie off Subject, point to From */
				/* find end of From */
    if (ov->date = strchr (t,'\t')) {
      *ov->date++ = '\0';	/* tie off From, point to Date */
				/* load internaldate too */
      if (!elt->day) mail_parse_date (elt,ov->date);
				/* parse From */
      rfc822_parse_adrlist (&ov->from,t,BADHOST);
				/* find end of Date */
      if (ov->message_id = strchr (ov->date,'\t')) {
				/* tie off Date, point to Message-ID */
	*ov->message_id++ = '\0';
				/* find end of Message-ID */
	if (ov->references = strchr (ov->message_id,'\t')) {
				/* tie off Message-ID, point to References */
	  *ov->references++ = '\0';
				/* fine end of References */
	  if (t = strchr (ov->references,'\t')) {
	    *t++ = '\0';	/* tie off References, point to octet size */
				/* parse size of message in octets */
	    ov->optional.octets = atol (t);
				/* find end of size */
	    if (t = strchr (t,'\t')) {
				/* parse size of message in lines */
	      ov->optional.lines = atol (++t);
				/* find Xref */
	      if (ov->optional.xref = strchr (t,'\t'))
		*ov->optional.xref++ = '\0';
	    }
	  }
	}
      }
    }
  }
  return ov->references ? T : NIL;
}

/* NNTP fetch header as text
 * Accepts: mail stream
 *	    message number
 *	    pointer to return size
 *	    flags
 * Returns: header text
 */

char *nntp_header (MAILSTREAM *stream,unsigned long msgno,unsigned long *size,
		   long flags)
{
  char tmp[MAILTMPLEN];
  MESSAGECACHE *elt;
  FILE *f;
  *size = 0;
  if ((flags & FT_UID) && !(msgno = mail_msgno (stream,msgno))) return "";
				/* have header text? */
  if (!(elt = mail_elt (stream,msgno))->private.msg.header.text.data) {
    sprintf (tmp,"%lu",mail_uid (stream,msgno));
				/* get header text */
    switch (nntp_send (LOCAL->nntpstream,"HEAD",tmp)) {
    case NNTPHEAD:
      if (f = netmsg_slurp (LOCAL->nntpstream->netstream,size,NIL)) {
	fread (elt->private.msg.header.text.data =
	       (unsigned char *) fs_get ((size_t) *size + 3),
	       (size_t) 1,(size_t) *size,f);
	fclose (f);		/* flush temp file */
				/* tie off header with extra CRLF and NUL */
	elt->private.msg.header.text.data[*size] = '\015';
	elt->private.msg.header.text.data[++*size] = '\012';
	elt->private.msg.header.text.data[++*size] = '\0';
	elt->private.msg.header.text.size = *size;
	elt->valid = T;		/* make elt valid now */
	break;
      }
				/* fall into default case */
    default:			/* failed, mark as deleted and empty */
      elt->valid = elt->deleted = T;
    case NNTPSOFTFATAL:		/* don't mark deleted if stream dead */
      *size = elt->private.msg.header.text.size = 0;
      break;
    }
  }
				/* just return size of text */
  else *size = elt->private.msg.header.text.size;
  return elt->private.msg.header.text.data ?
    (char *) elt->private.msg.header.text.data : "";
}

/* NNTP fetch body
 * Accepts: mail stream
 *	    message number
 *	    pointer to stringstruct to initialize
 *	    flags
 * Returns: T if successful, else NIL
 */

long nntp_text (MAILSTREAM *stream,unsigned long msgno,STRING *bs,long flags)
{
  char tmp[MAILTMPLEN];
  MESSAGECACHE *elt;
  INIT (bs,mail_string,(void *) "",0);
  if ((flags & FT_UID) && !(msgno = mail_msgno (stream,msgno))) return NIL;
  elt = mail_elt (stream,msgno);
				/* different message, flush cache */
  if (LOCAL->txt && (LOCAL->msgno != msgno)) {
    fclose (LOCAL->txt);