mbx.c

广泛使用的邮件服务器！同时

  SEARCHSET *dst = au ? mail_newsearchset () : NIL;
				/* make sure valid mailbox */
  if ((fd = mbx_isvalid (&dstream,mailbox,file,&ld,lock,
			 au ? MBXISVALIDUID : MBXISVALIDNOUID)) < 0)
    switch (errno) {
    case ENOENT:		/* no such file? */
      if (compare_cstring (mailbox,"INBOX")) {
	MM_NOTIFY (stream,"[TRYCREATE] Must create mailbox before append",NIL);
	return NIL;
      }
				/* can create INBOX here */
      mbx_create (dstream = stream ? stream : user_flags (&mbxproto),"INBOX");
      if ((fd = mbx_isvalid (&dstream,mailbox,file,&ld,lock,
			     au ? MBXISVALIDUID : MBXISVALIDNOUID)) >= 0)
	break;
    case EACCES:		/* file protected */
      sprintf (tmp,"Can't access destination: %.80s",mailbox);
      MM_LOG (tmp,ERROR);
      return NIL;
    case EINVAL:
      sprintf (tmp,"Invalid MBX-format mailbox name: %.80s",mailbox);
      MM_LOG (tmp,ERROR);
      return NIL;
    default:
      sprintf (tmp,"Not a MBX-format mailbox: %.80s",mailbox);
      MM_LOG (tmp,ERROR);
      return NIL;
    }

				/* get first message */
  if (!MM_APPEND (af) (dstream,data,&flags,&date,&message)) close (fd);
  else if (!(df = fdopen (fd,"r+b"))) {
    MM_LOG ("Unable to reopen append mailbox",ERROR);
    close (fd);
  }
  else {
    MM_CRITICAL (dstream);	/* go critical */
    fstat (fd,&sbuf);		/* get current file size */
    fseek (df,sbuf.st_size,SEEK_SET);
    errno = 0;
    for (ret = LONGT; ret && message; ) {
      if (!SIZE (message)) {	/* guard against zero-length */
	MM_LOG ("Append of zero-length message",ERROR);
	ret = NIL;
	break;
      }
      f = mail_parse_flags (dstream,flags,&uf);
      if (date) {		/* parse date if given */
	if (!mail_parse_date (&elt,date)) {
	  sprintf (tmp,"Bad date in append: %.80s",date);
	  MM_LOG (tmp,ERROR);
	  ret = NIL;		/* mark failure */
	  break;
	}
	mail_date (tmp,&elt);	/* write preseved date */
      }
      else internal_date (tmp);	/* get current date in IMAP format */
				/* write header */
      if (fprintf (df,"%s,%lu;%08lx%04lx-%08lx\015\012",tmp,i = SIZE (message),
		   uf,(unsigned long) f,au ? ++dstream->uid_last : 0) < 0)
	ret = NIL;
      else {			/* write message */
	size_t j;
	if (!message->cursize) SETPOS (message,GETPOS (message));
	while (i && (j = fwrite (message->curpos,1,message->cursize,df))) {
	  i -= j;
	  SETPOS (message,GETPOS (message) + j);
	}
				/* get next message */
	if (i || !MM_APPEND (af) (dstream,data,&flags,&date,&message))
	  ret = NIL;
	else if (au) mail_append_set (dst,dstream->uid_last);
      }
    }

				/* if error... */
    if (!ret || (fflush (df) == EOF)) {
				/* revert file */
      ftruncate (fd,sbuf.st_size);
      close (fd);		/* make sure fclose() doesn't corrupt us */
      if (errno) {
	sprintf (tmp,"Message append failed: %s",strerror (errno));
	MM_LOG (tmp,ERROR);
      }
      ret = NIL;
    }
    if (au && ret) {		/* return sets if doing APPENDUID */
      (*au) (mailbox,dstream->uid_validity,dst);
      fseek (df,15,SEEK_SET);	/* update UIDLAST */
      fprintf (df,"%08lx",dstream->uid_last);
    }
    else mail_free_searchset (&dst);
				/* set atime to now-1 if successful copy */
    if (ret) tp[0] = time (0) - 1;
				/* else preserve \Marked status */
    else tp[0] = (sbuf.st_ctime > sbuf.st_atime) ? sbuf.st_atime : time(0);
    tp[1] = sbuf.st_mtime;	/* preserve mtime */
    utime (file,tp);		/* set the times */
    fclose (df);		/* close the file */
    MM_NOCRITICAL (dstream);	/* release critical */
  }
  unlockfd (ld,lock);		/* release exclusive parse/append permission */
  if (dstream != stream) mail_close (dstream);
  return ret;
}

/* Internal routines */


/* MBX mail generate file string
 * Accepts: temporary buffer to write into
 *	    mailbox name string
 * Returns: local file string or NIL if failure
 */

char *mbx_file (char *dst,char *name)
{
  char *s = mailboxfile (dst,name);
  return (s && !*s) ? mailboxfile (dst,"~/INBOX") : s;
}

/* MBX mail parse mailbox
 * Accepts: MAIL stream
 * Returns: T if parse OK
 *	    NIL if failure, stream aborted
 */

long mbx_parse (MAILSTREAM *stream)
{
  struct stat sbuf;
  MESSAGECACHE *elt = NIL;
  unsigned char c,*s,*t,*x;
  char tmp[MAILTMPLEN];
  unsigned long i,j,k,m;
  off_t curpos = LOCAL->filesize;
  unsigned long nmsgs = stream->nmsgs;
  unsigned long recent = stream->recent;
  unsigned long lastuid = 0;
  short dirty = NIL;
  short added = NIL;
  short silent = stream->silent;
  short uidwarn = T;
  fstat (LOCAL->fd,&sbuf);	/* get status */
  if (sbuf.st_size < curpos) {	/* sanity check */
    sprintf (tmp,"Mailbox shrank from %lu to %lu!",
	     (unsigned long) curpos,(unsigned long) sbuf.st_size);
    MM_LOG (tmp,ERROR);
    mbx_abort (stream);
    return NIL;
  }
  lseek (LOCAL->fd,0,L_SET);	/* rewind file */
				/* read internal header */
  read (LOCAL->fd,LOCAL->buf,HDRSIZE);
  LOCAL->buf[HDRSIZE] = '\0';	/* tie off header */
  c = LOCAL->buf[15];		/* save first character of last UID */
  LOCAL->buf[15] = '\0';
				/* parse UID validity */
  stream->uid_validity = strtoul (LOCAL->buf + 7,NIL,16);
  LOCAL->buf[15] = c;		/* restore first character of last UID */
				/* parse last UID */
  i = strtoul (LOCAL->buf + 15,NIL,16);
  stream->uid_last = stream->rdonly ? max (i,stream->uid_last) : i;
				/* parse user flags */
  for (i = 0, s = LOCAL->buf + 25;
       (i < NUSERFLAGS) && (t = strchr (s,'\015')) && (t - s);
       i++, s = t + 2) {
    *t = '\0';			/* tie off flag */
    if (!stream->user_flags[i] && (strlen (s) <= MAXUSERFLAG))
      stream->user_flags[i] = cpystr (s);
  }
  LOCAL->ffuserflag = (int) i;	/* first free user flag */

				/* get current last flag updater PID */
  i = (isxdigit (LOCAL->buf[HDRSIZE-10]) && isxdigit (LOCAL->buf[HDRSIZE-9]) &&
       isxdigit (LOCAL->buf[HDRSIZE-8]) && isxdigit (LOCAL->buf[HDRSIZE-7]) &&
       isxdigit (LOCAL->buf[HDRSIZE-6]) && isxdigit (LOCAL->buf[HDRSIZE-5]) &&
       isxdigit (LOCAL->buf[HDRSIZE-4]) && isxdigit (LOCAL->buf[HDRSIZE-3]) &&
       (LOCAL->buf[HDRSIZE-2] == '\015') && (LOCAL->buf[HDRSIZE-1] == '\012'))?
    strtoul (LOCAL->buf + HDRSIZE - 8,NIL,16) : 0;
				/* set flagcheck if lastpid changed */
  if (LOCAL->lastpid && (LOCAL->lastpid != i)) LOCAL->flagcheck = T;
  LOCAL->lastpid = i;		/* set as last PID */
  stream->silent = T;		/* don't pass up exists events yet */
  while (sbuf.st_size - curpos){/* while there is stuff to parse */
				/* get to that position in the file */
    lseek (LOCAL->fd,curpos,L_SET);
    if ((i = read (LOCAL->fd,LOCAL->buf,64)) <= 0) {
      sprintf (tmp,"Unable to read internal header at %lu, size = %lu: %s",
	       (unsigned long) curpos,(unsigned long) sbuf.st_size,
	       i ? strerror (errno) : "no data read");
      MM_LOG (tmp,ERROR);
      mbx_abort (stream);
      return NIL;
    }
    LOCAL->buf[i] = '\0';	/* tie off buffer just in case */
    if (!((s = strchr (LOCAL->buf,'\015')) && (s[1] == '\012'))) {
      sprintf (tmp,"Unable to find CRLF at %lu in %lu bytes, text: %.80s",
	       (unsigned long) curpos,i,(char *) LOCAL->buf);
      MM_LOG (tmp,ERROR);
      mbx_abort (stream);
      return NIL;
    }
    *s = '\0';			/* tie off header line */
    i = (s + 2) - LOCAL->buf;	/* note start of text offset */
    if (!((s = strchr (LOCAL->buf,',')) && (t = strchr (s+1,';')))) {
      sprintf (tmp,"Unable to parse internal header at %lu: %.80s",
	       (unsigned long) curpos,(char *) LOCAL->buf);
      MM_LOG (tmp,ERROR);
      mbx_abort (stream);
      return NIL;
    }
    if (!(isxdigit (t[1]) && isxdigit (t[2]) && isxdigit (t[3]) &&
	  isxdigit (t[4]) && isxdigit (t[5]) && isxdigit (t[6]) &&
	  isxdigit (t[7]) && isxdigit (t[8]) && isxdigit (t[9]) &&
	  isxdigit (t[10]) && isxdigit (t[11]) && isxdigit (t[12]))) {
      sprintf (tmp,"Unable to parse message flags at %lu: %.80s",
	       (unsigned long) curpos,(char *) LOCAL->buf);
      MM_LOG (tmp,ERROR);
      mbx_abort (stream);
      return NIL;
    }
    if ((t[13] != '-') || t[22] ||
	!(isxdigit (t[14]) && isxdigit (t[15]) && isxdigit (t[16]) &&
	  isxdigit (t[17]) && isxdigit (t[18]) && isxdigit (t[19]) &&
	  isxdigit (t[20]) && isxdigit (t[21]))) {
      sprintf (tmp,"Unable to parse message UID at %lu: %.80s",
	       (unsigned long) curpos,(char *) LOCAL->buf);
      MM_LOG (tmp,ERROR);
      mbx_abort (stream);
      return NIL;
    }

    *s++ = '\0'; *t++ = '\0';	/* break up fields */
				/* get message size */
    if (!(j = strtoul (s,(char **) &x,10)) && (!(x && *x))) {
      sprintf (tmp,"Unable to parse message size at %lu: %.80s,%.80s;%.80s",
	       (unsigned long) curpos,(char *) LOCAL->buf,(char *) s,
	       (char *) t);
      MM_LOG (tmp,ERROR);
      mbx_abort (stream);
      return NIL;
    }
				/* make sure didn't run off end of file */
    if (((off_t) (curpos + i + j)) > sbuf.st_size) {
      sprintf (tmp,"Last message (at %lu) runs past end of file (%lu > %lu)",
	       (unsigned long) curpos,(unsigned long) (curpos + i + j),
	       (unsigned long) sbuf.st_size);
      MM_LOG (tmp,ERROR);
      mbx_abort (stream);
      return NIL;
    }
				/* parse UID */
    if ((m = strtoul (t+13,NIL,16)) &&
	((m <= lastuid) || (m > stream->uid_last))) {
      if (uidwarn) {
	sprintf (tmp,"Invalid UID %08lx in message %lu, rebuilding UIDs",
		 m,nmsgs+1);
	MM_LOG (tmp,WARN);
	uidwarn = NIL;
				/* restart UID validity */
	stream->uid_validity = time (0);
      }
      m = 0;			/* lose this UID */
      dirty = T;		/* mark dirty, set new lastuid */
      stream->uid_last = lastuid;
    }

    t[12] = '\0';		/* parse system flags */
    if ((k = strtoul (t+8,NIL,16)) & fEXPUNGED) {
      if (m) lastuid = m;	/* expunge message, update last UID seen */
      else {			/* no UID assigned? */
	lastuid = ++stream->uid_last;
	dirty = T;
      }
    }
    else {			/* not expunged, swell the cache */
      added = T;		/* note that a new message was added */
      mail_exists (stream,++nmsgs);
				/* instantiate an elt for this message */
      (elt = mail_elt (stream,nmsgs))->valid = T;
				/* parse the date */
      if (!mail_parse_date (elt,LOCAL->buf)) {
	sprintf (tmp,"Unable to parse message date at %lu: %.80s",
		 (unsigned long) curpos,(char *) LOCAL->buf);
	MM_LOG (tmp,ERROR);
	mbx_abort (stream);
	return NIL;
      }
				/* note file offset of header */
      elt->private.special.offset = curpos;
				/* and internal header size */
      elt->private.special.text.size = i;
				/* header size not known yet */
      elt->private.msg.header.text.size = 0;
      elt->rfc822_size = j;	/* note message size */
				/* calculate system flags */
      if (k & fSEEN) elt->seen = T;
      if (k & fDELETED) elt->deleted = T;
      if (k & fFLAGGED) elt->flagged = T;
      if (k & fANSWERED) elt->answered = T;
      if (k & fDRAFT) elt->draft = T;
      t[8] = '\0';		/* get user flags value */
      elt->user_flags = strtoul (t,NIL,16);
				/* UID already assigned? */
      if (!(elt->private.uid = m) || !(k & fOLD)) {
	elt->recent = T;	/* no, mark as recent */
	++recent;		/* count up a new recent message */
	dirty = T;		/* and must rewrite header */
				/* assign new UID */
	if (!elt->private.uid) elt->private.uid = ++stream->uid_last;
	mbx_update_status (stream,elt->msgno,NIL);
      }
				/* update last parsed UID */
      lastuid = elt->private.uid;
    }
    curpos += i + j;		/* update position */
  }

  if (dirty && !stream->rdonly){/* update header */
    mbx_update_header (stream);
    fsync (LOCAL->fd);		/* make sure all the UID updates take */
  }
				/* update parsed file size and time */
  LOCAL->filesize = sbuf.st_size;
  fstat (LOCAL->fd,&sbuf);	/* get status again to ensure time is right */
  LOCAL->filetime = sbuf.st_mtime;
  if (added && !stream->rdonly){/* make sure atime updated */
    time_t tp[2];
    tp[0] = time (0);
    tp[1] = LOCAL->filetime;
    utime (stream->mailbox,tp);
  }
  stream->silent = silent;	/* can pass up events now */
  mail_exists (stream,nmsgs);	/* notify upper level of new mailbox size */
  mail_recent (stream,recent);	/* and of change in recent messages */
  return LONGT;			/* return the winnage */
}

/* MBX get cache element with status updating from file
 * Accepts: MAIL stream
 *	    message number
 *	    expunge OK flag
 * Returns: cache element
 */

MESSAGECACHE *mbx_elt (MAILSTREAM *stream,unsigned long msgno,long expok)
{
  MESSAGECACHE *elt = mail_elt (stream,msgno);
  struct {			/* old flags */
    unsigned int seen : 1;
    unsigned int deleted : 1;
    unsigned int flagged : 1;
    unsigned int answered : 1;
    unsigned int draft : 1;
    unsigned long user_flags;
  } old;
  old.seen = elt->seen; old.deleted = elt->deleted; old.flagged = elt->flagged;
  old.answered = elt->answered; old.draft = elt->draft;
  old.user_flags = elt->user_flags;
				/* get new flags */
  if (mbx_read_flags (stream,elt) && expok) {
    mail_expunged (stream,elt->msgno);
    return NIL;			/* return this message was expunged */
  }
  if ((old.seen != elt->seen) || (old.deleted != elt->deleted) ||
      (old.flagged != elt->flagged) || (old.answered != elt->answered) ||
      (old.draft != elt->draft) || (old.user_flags != elt->user_flags))
    MM_FLAGS (stream,msgno);	/* let top level know */
  return elt;
}

/* MBX read flags from file