newsrc.c

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  unsigned long m = 1,recent = 0,unseen = 0;
  FILE *f = fopen ((char *) mail_parameters (stream,GET_NEWSRC,stream),"rb");
  if (f) do {			/* read newsrc */
    for (s = tmp; (s < (tmp + MAILTMPLEN - 1)) && ((c = getc (f)) != EOF) &&
	 (c != ':') && (c != '!') && (c != '\015') && (c != '\012'); *s++ = c);
    *s = '\0';			/* tie off name */
    if ((c==':') || (c=='!')) {	/* found newsgroup? */
      if (strcmp (tmp,group))	/* group name match? */
	while ((c != '\015') && (c != '\012') && (c != EOF)) c = getc (f);
      else {			/* yes, skip leading whitespace */
	while ((c = getc (f)) == ' ');
				/* only if unprocessed messages */
	if (stream->nmsgs) while (f && (m <= stream->nmsgs)) {
				/* collect a number */
	  if (isdigit (c)) {	/* better have a number */
	    for (i = 0,j = 0; isdigit (c); c = getc (f)) i = i*10 + (c-'0');
	    if (c == '-') for (c = getc (f); isdigit (c); c = getc (f))
	      j = j*10 +(c-'0');/* collect second value if range */
	    if (!unseen && (mail_elt (stream,m)->private.uid < i)) unseen = m;
				/* skip messages before first value */
	    while ((m <= stream->nmsgs) &&
		   ((elt = mail_elt (stream,m))->private.uid < i) && m++)
	      elt->valid = T;
				/* do all messages in range */
	    while ((m <= stream->nmsgs) && (elt = mail_elt (stream,m)) &&
		   (j ? ((elt->private.uid >= i) && (elt->private.uid <= j)) :
		    (elt->private.uid == i)) && m++)
	      elt->valid = elt->deleted = T;
	  }

	  switch (c) {		/* what is the delimiter? */
	  case ',':		/* more to come */
	    c = getc (f);	/* get first character of number */
	    break;
	  default:		/* bogus character */
	    sprintf (tmp,"Bogus character 0x%x in news state",(unsigned int)c);
	    MM_LOG (tmp,ERROR);
	  case EOF: case '\015': case '\012':
	    fclose (f);		/* all done - close the file */
	    f = NIL;
	    break;
	  }
	}
	else {			/* empty newsgroup */
	  while ((c != '\015') && (c != '\012') && (c != EOF)) c = getc (f);
	  fclose (f);		/* all done - close the file */
	  f = NIL;
	}
      }
    }
  } while (f && (c != EOF));	/* until file closed or EOF */
  if (f) {			/* still have file open? */
    sprintf (tmp,"No state for newsgroup %.80s found, reading as new",group);
    MM_LOG (tmp,WARN);
    fclose (f);			/* close the file */
  }
  if (m <= stream->nmsgs) {	/* any messages beyond newsrc range? */
    if (!unseen) unseen = m;	/* then this must be the first unseen one */
    do {
      elt = mail_elt (stream,m++);
      elt->valid = elt->recent = T;
      ++recent;			/* count another recent message */
    }
    while (m <= stream->nmsgs);
  }
  if (unseen) {			/* report first unseen message */
    sprintf (tmp,"[UNSEEN] %lu is first unseen message in %.80s",unseen,group);
    MM_NOTIFY (stream,tmp,(long) NIL);
  }
  return recent;
}

/* Update newsgroup entry in newsrc
 * Accepts: newsgroup name
 *	    MAIL stream
 * Returns: T if successful, NIL otherwise
 */

long newsrc_write (char *group,MAILSTREAM *stream)
{
  long ret = NIL;
  int c = 0,d = EOF;
  char *newsrc = (char *) mail_parameters (stream,GET_NEWSRC,stream);
  char *s,tmp[MAILTMPLEN],backup[MAILTMPLEN],nl[3];
  FILE *f,*bf;
  nl[0] = nl[1] = nl[2] = '\0';	/* no newline known yet */
  if (f = fopen (newsrc,"rb")) {/* have existing newsrc file? */
    if (!(bf = fopen ((strcat (strcpy (backup,newsrc),OLDFILESUFFIX)),"wb"))) {
      fclose (f);		/* punt input file */
      return newsrc_error("Can't create backup news state %.80s",backup,ERROR);
    }
				/* copy to backup file */
    while ((c = getc (f)) != EOF) {
				/* need to know about newlines and found it? */
      if (!nl[0] && ((c == '\015') || (c == '\012')) && ((nl[0]=c) == '\015')){
				/* sniff and see if an LF */
	if ((c = getc (f)) == '\012') nl[1] = c;
	ungetc (c,f);		/* push it back */
      }
				/* write to backup file */
      if ((d = putc (c,bf)) == EOF) {
	fclose (f);		/* punt input file */
	return newsrc_error ("Error writing backup news state %.80s",
			     newsrc,ERROR);
      }
    }
    fclose (f);			/* close existing file */
    if (fclose (bf) == EOF)	/* and backup file */
      return newsrc_error ("Error closing backup news state %.80s",
			   newsrc,ERROR);
    if (d == EOF) {		/* open for write if empty file */
      if (f = newsrc_create (stream,NIL)) bf = NIL;
      else return NIL;
    }
    else if (!nl[0])		/* make sure newlines valid */
      return newsrc_error ("Unknown newline convention in %.80s",newsrc,ERROR);
				/* now read backup file */
    else if (!(bf = fopen (backup,"rb")))
      return newsrc_error ("Error reading backup news state %.80s",
			   backup,ERROR);
				/* open newsrc for writing */
    else if (!(f = fopen (newsrc,"wb"))) {
      fclose (bf);		/* punt backup */
      return newsrc_error ("Can't rewrite news state %.80s",newsrc,ERROR);
    }
  }
  else {			/* create new newsrc file */
    if (f = newsrc_create (stream,T)) bf = NIL;
    else return NIL;		/* can't create newsrc */
  }
  
  while (bf) {			/* read newsrc */
    for (s = tmp; (s < (tmp + MAILTMPLEN - 1)) && ((c = getc (bf)) != EOF) &&
	 (c != ':') && (c != '!') && (c != '\015') && (c != '\012'); *s++ = c);
    *s = '\0';			/* tie off name */
				/* saw correct end of group delimiter? */
    if (tmp[0] && ((c == ':') || (c == '!'))) {
				/* yes, write newsgroup name and delimiter */
      if ((tmp[0] && (fputs (tmp,f) == EOF)) || ((putc (c,f)) == EOF))
	return newsrc_write_error (newsrc,bf,f);
      if (!strcmp (tmp,group)) {/* found correct group? */
				/* yes, write new status */
	if (!newsrc_newmessages (f,stream,nl[0] ? nl : "\n"))
	  return newsrc_write_error (newsrc,bf,f);
				/* skip past old data */
	while (((c = getc (bf)) != EOF) && (c != '\015') && (c != '\012'));
				/* skip past newline */
	while ((c == '\015') || (c == '\012')) c = getc (bf);
	while (c != EOF) {	/* copy remainder of file */
	  if (putc (c,f) == EOF) return newsrc_write_error (newsrc,bf,f);
	  c = getc (bf);	/* get next character */
	}
				/* done with file */
	if (fclose (f) == EOF) return newsrc_write_error (newsrc,bf,NIL);
	f = NIL;
      }
				/* copy remainder of line */
      else while (((c = getc (bf)) != EOF) && (c != '\015') && (c != '\012'))
	if (putc (c,f) == EOF) return newsrc_write_error (newsrc,bf,f);
      if (c == '\015') {	/* write CR if seen */
	if (putc (c,f) == EOF) return newsrc_write_error (newsrc,bf,f);
				/* sniff to see if LF */
	if (((c = getc (bf)) != EOF) && (c != '\012')) ungetc (c,bf);
      }
				/* write LF if seen */
      if ((c == '\012') && (putc (c,f) == EOF))
	return newsrc_write_error (newsrc,bf,f);
    }
    if (c == EOF) {		/* hit end of file? */
      fclose (bf);		/* yup, close the file */
      bf = NIL;
    }
  }
  if (f) {			/* still have newsrc file open? */
    ret = ((fputs (group,f) != EOF) && ((putc (':',f)) != EOF) &&
	   newsrc_newmessages (f,stream,nl[0] ? nl : "\n")) ? LONGT : NIL;
    if (fclose (f) == EOF) ret = newsrc_write_error (newsrc,NIL,NIL);
  }
  else ret = LONGT;
  return ret;
}

/* Get newsgroup state as text stream
 * Accepts: MAIL stream
 *	    newsgroup name
 * Returns: string containing newsgroup state, or NIL if not found
 */

char *newsrc_state (MAILSTREAM *stream,char *group)
{
  int c = 0;
  char *s,tmp[MAILTMPLEN];
  long pos;
  size_t size;
  FILE *f = fopen ((char *) mail_parameters (stream,GET_NEWSRC,stream),"rb");
  if (f) do {			/* read newsrc */
    for (s = tmp; (s < (tmp + MAILTMPLEN - 1)) && ((c = getc (f)) != EOF) &&
	 (c != ':') && (c != '!') && (c != '\015') && (c != '\012'); *s++ = c);
    *s = '\0';			/* tie off name */
    if ((c==':') || (c=='!')) {	/* found newsgroup? */
      if (strcmp (tmp,group))	/* group name match? */
	while ((c != '\015') && (c != '\012') && (c != EOF)) c = getc (f);
      else {			/* yes, skip leading whitespace */
	do pos = ftell (f);
	while ((c = getc (f)) == ' ');
				/* count characters in state */
	for (size = 0; (c != '\015') && (c != '\012') && (c != EOF); size++)
	  c = getc (f);
				/* now copy it */
	s = (char *) fs_get (size + 1);
	fseek (f,pos,SEEK_SET);
	fread (s,(size_t) 1,size,f);
	s[size] = '\0';		/* tie off string */
	fclose (f);		/* all done - close the file */
	return s;
      }
    }
  } while (f && (c != EOF));	/* until file closed or EOF */
  sprintf (tmp,"No state for newsgroup %.80s found",group);
  MM_LOG (tmp,WARN);
  if (f) fclose (f);		/* close the file */
  return NIL;			/* not found return */
}

/* Check UID in newsgroup state
 * Accepts: newsgroup state string
 *	    uid
 *	    returned recent count
 *	    returned unseen count
 */

void newsrc_check_uid (unsigned char *state,unsigned long uid,
		       unsigned long *recent,unsigned long *unseen)
{
  unsigned long i,j;
  while (*state) {		/* until run out of state string */
				/* collect a number */
    for (i = 0; isdigit (*state); i = i*10 + (*state++ - '0'));
    if (*state != '-') j = i;	/* coerce single mesage into range */
    else {			/* have a range */
      for (j = 0; isdigit (*++state); j = j*10 + (*state - '0'));
      if (!j) j = i;		/* guard against -0 */
      if (j < i) return;	/* bogon if end less than start */
    }
    if (*state == ',') state++;	/* skip past comma */
    else if (*state) return;	/* otherwise it's a bogon */
    if (uid <= j) {		/* covered by upper bound? */
      if (uid < i) ++*unseen;	/* unseen if not covered by lower bound */
      return;			/* don't need to look further */
    }
  }
  ++*unseen;			/* not found in any range, message is unseen */
  ++*recent;			/* and recent */
}