unix.c

Vovida 社区开源的 SIP 协议源码

    unix_abort (stream);
    mail_unlock (stream);
    mm_nocritical (stream);	/* done with critical */
    return NIL;
  }

				/* new data? */
  else if (i = sbuf.st_size - LOCAL->filesize) {
    d.fd = LOCAL->fd;		/* yes, set up file descriptor */
    d.pos = LOCAL->filesize;	/* get to that position in the file */
    d.chunk = LOCAL->buf;	/* initial buffer chunk */
    d.chunksize = CHUNK;	/* file chunk size */
    INIT (&bs,fd_string,&d,i);	/* initialize stringstruct */
				/* skip leading whitespace for broken MTAs */
    while (((c = CHR (&bs)) == '\n') || (c == '\r') ||
	   (c == ' ') || (c == '\t')) SNX (&bs);
    if (SIZE (&bs)) {		/* read new data */
				/* remember internal header position */
      j = LOCAL->filesize + GETPOS (&bs);
      s = unix_mbxline (stream,&bs,&i);
      t = NIL,zn = 0;
      if (i) VALID (s,t,ti,zn);	/* see if valid From line */
      if (!ti) {		/* someone pulled the rug from under us */
	sprintf(tmp,"Unexpected changes to mailbox (try restarting): %.20s",s);
	mm_log (tmp,ERROR);
	unix_unlock (LOCAL->fd,stream,lock);
	unix_abort (stream);
	mail_unlock (stream);
	mm_nocritical (stream);	/* done with critical */
	return NIL;
      }
      stream->silent = T;	/* quell main program new message events */
      do {			/* found a message */
				/* instantiate first new message */
	mail_exists (stream,++nmsgs);
	(elt = mail_elt (stream,nmsgs))->valid = T;
	recent++;		/* assume recent by default */
	elt->recent = T;
				/* note position/size of internal header */
	elt->private.special.offset = j;
	elt->private.msg.header.offset = elt->private.special.text.size = i;

				/* generate plausible IMAPish date string */
	date[2] = date[6] = date[20] = '-'; date[11] = ' ';
	date[14] = date[17] = ':';
				/* dd */
	date[0] = t[ti - 2]; date[1] = t[ti - 1];
				/* mmm */
	date[3] = t[ti - 6]; date[4] = t[ti - 5]; date[5] = t[ti - 4];
				/* hh */
	date[12] = t[ti + 1]; date[13] = t[ti + 2];
				/* mm */
	date[15] = t[ti + 4]; date[16] = t[ti + 5];
	if (t[ti += 6] == ':') {/* ss */
	  date[18] = t[++ti]; date[19] = t[++ti];
	  ti++;			/* move to space */
	}
	else date[18] = date[19] = '0';
				/* yy -- advance over timezone if necessary */
	if (zn == ti) ti += (((t[zn+1] == '+') || (t[zn+1] == '-')) ? 6 : 4);
	date[7] = t[ti + 1]; date[8] = t[ti + 2];
	date[9] = t[ti + 3]; date[10] = t[ti + 4];
				/* zzz */
	t = zn ? (t + zn + 1) : "LCL";
	date[21] = *t++; date[22] = *t++; date[23] = *t++;
	if ((date[21] != '+') && (date[21] != '-')) date[24] = '\0';
	else {			/* numeric time zone */
	  date[24] = *t++; date[25] = *t++;
	  date[26] = '\0'; date[20] = ' ';
	}
				/* set internal date */
	if (!mail_parse_date (elt,date)) {
	  sprintf (tmp,"Unable to parse internal date: %s",date);
	  mm_log (tmp,WARN);
	}

	do {			/* look for message body */
	  s = t = unix_mbxline (stream,&bs,&i);
	  if (i) switch (*s) {	/* check header lines */
	  case 'X':		/* possible X-???: line */
	    if (s[1] == '-') {	/* must be immediately followed by hyphen */
				/* X-Status: becomes Status: in S case */
	      if (s[2] == 'S' && s[3] == 't' && s[4] == 'a' && s[5] == 't' &&
		  s[6] == 'u' && s[7] == 's' && s[8] == ':') s += 2;
				/* possible X-Keywords */
	      else if (s[2] == 'K' && s[3] == 'e' && s[4] == 'y' &&
		       s[5] == 'w' && s[6] == 'o' && s[7] == 'r' &&
		       s[8] == 'd' && s[9] == 's' && s[10] == ':') {
		char uf[MAILTMPLEN];
		retain = NIL;	/* don't retain continuation */
		s += 11;	/* flush leading whitespace */
		while (*s && (*s != '\n') && ((*s != '\r') || (s[1] != '\n'))){
		  while (*s == ' ') s++;
				/* find end of keyword */
		  if (!(u = strpbrk (s," \n\r"))) u = s + strlen (s);
				/* got a keyword? */
		  if ((k = (u - s)) && (k < MAXUSERFLAG)) {
				/* copy keyword */
		    strncpy (uf,s,k);
		    uf[k] = '\0';/* make sure tied off */
		    ucase (uf);	/* coerce upper case */
		    for (j = 0; (j<NUSERFLAGS) && stream->user_flags[j]; ++j)
		      if (!strcmp(uf,
				  ucase (strcpy(tmp,stream->user_flags[j])))) {
			elt->user_flags |= ((long) 1) << j;
			break;
		      }
 		  }
		  s = u;	/* advance to next keyword */
		}
		break;
	      }

				/* possible X-IMAP */
	      else if ((s[2] == 'I') && (s[3] == 'M') && (s[4] == 'A') &&
		       (s[5] == 'P') && ((m = (s[6] == ':')) ||
					 ((s[6] == 'b') && (s[7] == 'a') &&
					  (s[8] == 's') && (s[9] == 'e') &&
					  (s[10] == ':')))) {
		retain = NIL;	/* don't retain continuation */
		if ((nmsgs == 1) && !stream->uid_validity) {
				/* advance to data */
		  s += m ? 7 : 11;
				/* flush whitespace */
		  while (*s == ' ') s++;
		  j = 0;	/* slurp UID validity */
				/* found a digit? */
		  while (isdigit (*s)) {
		    j *= 10;	/* yes, add it in */
		    j += *s++ - '0';
		  }
				/* flush whitespace */
		  while (*s == ' ') s++;
				/* must have valid UID validity and UID last */
		  if (j && isdigit (*s)) {
				/* pseudo-header seen if X-IMAP */
		    if (m) pseudoseen = LOCAL->pseudo = T;
				/* save UID validity */
		    stream->uid_validity = j;
		    j = 0;	/* slurp UID last */
		    while (isdigit (*s)) {
		      j *= 10;	/* yes, add it in */
		      j += *s++ - '0';
		    }
				/* save UID last */
		    stream->uid_last = j;
				/* process keywords */
		    for (j = 0; (*s != '\n') && ((*s != '\r')||(s[1] != '\n'));
			 s = u,j++) {
				/* flush leading whitespace */
		      while (*s == ' ') s++;
		      u = strpbrk (s," \n\r");
				/* got a keyword? */
		      if ((k = (u - s)) && j < NUSERFLAGS) {
			if (stream->user_flags[j])
			  fs_give ((void **) &stream->user_flags[j]);
			stream->user_flags[j] = (char *) fs_get (k + 1);
			strncpy (stream->user_flags[j],s,k);
			stream->user_flags[j][k] = '\0';
		      }
		    }
		  }
		}
		break;
	      }

				/* possible X-UID */
	      else if (s[2] == 'U' && s[3] == 'I' && s[4] == 'D' &&
		       s[5] == ':') {
		retain = NIL;	/* don't retain continuation */
				/* only believe if have a UID validity */
		if (stream->uid_validity && ((nmsgs > 1) || !pseudoseen)) {
		  s += 6;	/* advance to UID value */
				/* flush whitespace */
		  while (*s == ' ') s++;
		  j = 0;
				/* found a digit? */
		  while (isdigit (*s)) {
		    j *= 10;	/* yes, add it in */
		    j += *s++ - '0';
		  }
				/* flush remainder of line */
		  while (*s != '\n') s++;
				/* make sure not duplicated */
		  if (elt->private.uid)
		    sprintf (tmp,"Message %lu UID %lu already has UID %lu",
			     pseudoseen ? elt->msgno - 1 : elt->msgno,
			     j,elt->private.uid);
				/* make sure UID doesn't go backwards */
		  else if (j <= prevuid)
		    sprintf (tmp,"Message %lu UID %lu less than %lu",
			     pseudoseen ? elt->msgno - 1 : elt->msgno,
			     j,prevuid + 1);
				/* or skip by mailbox's recorded last */
		  else if (j > stream->uid_last)
		    sprintf (tmp,"Message %lu UID %lu greater than last %lu",
			     pseudoseen ? elt->msgno - 1 : elt->msgno,
			     j,stream->uid_last);
		  else {	/* normal UID case */
		    prevuid = elt->private.uid = j;
		    break;	/* exit this cruft */
		  }
		  mm_log (tmp,WARN);
				/* invalidate UID validity */
		  stream->uid_validity = 0;
		  elt->private.uid = 0;
		}
		break;
	      }
	    }
				/* otherwise fall into S case */

	  case 'S':		/* possible Status: line */
	    if (s[0] == 'S' && s[1] == 't' && s[2] == 'a' && s[3] == 't' &&
		s[4] == 'u' && s[5] == 's' && s[6] == ':') {
	      retain = NIL;	/* don't retain continuation */
	      s += 6;		/* advance to status flags */
	      do switch (*s++) {/* parse flags */
	      case 'R':		/* message read */
		elt->seen = T;
		break;
	      case 'O':		/* message old */
		if (elt->recent) {
		  elt->recent = NIL;
		  recent--;	/* it really wasn't recent */
		}
		break;
	      case 'D':		/* message deleted */
		elt->deleted = T;
		break;
	      case 'F':		/* message flagged */
		elt->flagged = T;
		break;
	      case 'A':		/* message answered */
		elt->answered = T;
		break;
	      case 'T':		/* message is a draft */
		elt->draft = T;
		break;
	      default:		/* some other crap */
		break;
	      } while (*s && (*s != '\n') && ((*s != '\r') || (s[1] != '\n')));
	      break;		/* all done */
	    }
				/* otherwise fall into default case */

	  default:		/* ordinary header line */
	    if ((*s == 'S') || (*s == 's') ||
		(((*s == 'X') || (*s == 'x')) && (s[1] == '-'))) {
	      char *e,*v;
				/* must match what mail_filter() does */
	      for (u = s,v = tmp,e = u + min (i,MAILTMPLEN - 1);
		   (u < e) && ((c = *u) != ':') &&
		   ((c > ' ') || ((c != ' ') && (c != '\t') &&
				  (c != '\015') && (c != '\012')));
		   *v++ = *u++);
	      *v = '\0';	/* tie off */
				/* matches internal header? */
	      if (!strcmp (ucase (tmp),"STATUS") || !strcmp (tmp,"X-STATUS") ||
		  !strcmp (tmp,"X-KEYWORDS") || !strcmp (tmp,"X-UID") ||
		  !strcmp (tmp,"X-IMAP") || !strcmp (tmp,"X-IMAPBASE")) {
		char err[MAILTMPLEN];
		sprintf (err,"Discarding bogus %s header in message %lu",
			 tmp,elt->msgno);
		mm_log (err,WARN);
		retain = NIL;	/* don't retain continuation */
		break;		/* different case or something */
	      }
	    }
				/* retain or non-continuation? */
	    if (retain || ((*s != ' ') && (*s != '\t'))) {
	      retain = T;	/* retaining continuation now */
				/* line length in LF format newline */
	      k = i - (((i >= 2) && (s[i - 2] == '\r')) ? 1 : 0);
				/* "internal" header size */
	      elt->private.data += k;
				/* message size */
	      elt->rfc822_size += k + 1;
	    }
	    else {
	      char err[MAILTMPLEN];
	      sprintf (err,"Discarding bogus continuation in message %lu: ",
		       elt->msgno);
	      u = strncpy (err + strlen (err),s,(size_t) max (i,80));
	      u[80] = '\0';	/* make sure tired off */
	      if (u = strpbrk (u,"\r\n")) *u = '\0';
	      mm_log (err,WARN);
	      break;		/* different case or something */
	    }
	    break;
	  }
	} while (i && (*t != '\n') && ((*t != '\r') || (t[1] != '\n')));
				/* "internal" header sans trailing newline */
	if (i) elt->private.data--;
				/* assign a UID if none found */
	if (((nmsgs > 1) || !pseudoseen) && !elt->private.uid) {
	  prevuid = elt->private.uid = ++stream->uid_last;
	  elt->private.dirty = T;
	}
	else elt->private.dirty = elt->recent;

				/* note size of header, location of text */
	elt->private.msg.header.text.size = 
	  (elt->private.msg.text.offset =
	   (LOCAL->filesize + GETPOS (&bs)) - elt->private.special.offset) -
	     elt->private.special.text.size;
	k = m = 0;		/* no previous line size yet */
				/* note current position */
	j = LOCAL->filesize + GETPOS (&bs);
	if (i) do {		/* look for next message */
	  s = unix_mbxline (stream,&bs,&i);
	  if (i) {		/* got new data? */
	    VALID (s,t,ti,zn);	/* yes, parse line */
	    if (!ti) {		/* not a header line, add it to message */
	      elt->rfc822_size += 
		k = i + (m = (((i < 2) || s[i - 2] != '\r') ? 1 : 0));
				/* update current position */
	      j = LOCAL->filesize + GETPOS (&bs);
	    }
	  }
	} while (i && !ti);	/* until found a header */
	elt->private.msg.text.text.size = j -
	  (elt->private.special.offset + elt->private.msg.text.offset);
	if (k == 2) {		/* last line was blank? */
	  elt->private.msg.text.text.size -= (m ? 1 : 2);
	  elt->rfc822_size -= 2;
	}
      } while (i);		/* until end of buffer */
      if (pseudoseen) {		/* flush pseudo-message if present */
				/* decrement recent count */
	if (mail_elt (stream,1)->recent) recent--;
				/* and the exists count */
	mail_exists (stream,nmsgs--);
	mail_expunged(stream,1);/* fake an expunge of that message */
      }
				/* need to start a new UID validity? */
      if (!stream->uid_validity) {
	stream->uid_validity = time (0);
				/* in case a whiner with no life */
	if (mail_parameters (NIL,GET_USERHASNOLIFE,NIL))
	  stream->uid_nosticky = T;
	else if (nmsgs) {	/* don't bother if empty file */
	  LOCAL->dirty = T;	/* make dirty to restart UID epoch */
				/* need to rewrite msg 1 if not pseudo */
	  if (!LOCAL->pseudo) mail_elt (stream,1)->private.dirty = T;
	  mm_log ("Assigning new unique identifiers to all messages",NIL);
	}
      }
      stream->nmsgs = oldnmsgs;	/* whack it back down */
      stream->silent = silent;	/* restore old silent setting */
				/* notify upper level of new mailbox sizes */
      mail_exists (stream,nmsgs);
      mail_recent (stream,recent);
				/* mark dirty so O flags are set */
      if (recent) LOCAL->dirty = T;
    }
  }
				/* no change, don't babble if never got time */
  else if (LOCAL->filetime && LOCAL->filetime != sbuf.st_mtime)
    mm_log ("New mailbox modification time but apparently no changes",WARN);
				/* update parsed file size and time */
  LOCAL->filesize = sbuf.st_size;
  LOCAL->filetime = sbuf.st_mtime;
  return T;			/* return the winnage */
}

/* UNIX read line from mailbox
 * Accepts: mail stream
 *	    stringstruct
 *	    pointer to line size
 * Returns: pointer to input line
 */

char *unix_mbxline (MAILSTREAM *stream,STRING *bs,unsigned long *size)
{