mbxnt.c

广泛使用的邮件服务器！同时

 * Returns: T if success, NIL if failed
 */

long mbx_copy (MAILSTREAM *stream,char *sequence,char *mailbox,long options)
{
  struct stat sbuf;
  struct utimbuf times;
  MESSAGECACHE *elt;
  unsigned long i,j,k,m;
  long ret = LONGT;
  int fd,ld;
  char *s,*t,file[MAILTMPLEN],lock[MAILTMPLEN];
  mailproxycopy_t pc =
    (mailproxycopy_t) mail_parameters (stream,GET_MAILPROXYCOPY,NIL);
  copyuid_t cu = (copyuid_t) mail_parameters (NIL,GET_COPYUID,NIL);
  SEARCHSET *source = cu ? mail_newsearchset () : NIL;
  SEARCHSET *dest = cu ? mail_newsearchset () : NIL;
  MAILSTREAM *dstream = NIL;
  if (!((options & CP_UID) ? mail_uid_sequence (stream,sequence) :
	mail_sequence (stream,sequence))) return NIL;
				/* make sure valid mailbox */
  if ((fd = mbx_isvalid (&dstream,mailbox,file,&ld,lock,
			 cu ? MBXISVALIDUID : MBXISVALIDNOUID)) < 0)
    switch (errno) {
    case ENOENT:		/* no such file? */
      mm_notify (stream,"[TRYCREATE] Must create mailbox before copy",NIL);
      return NIL;
    case EACCES:		/* file protected */
      sprintf (LOCAL->buf,"Can't access destination: %.80s",mailbox);
      MM_LOG (LOCAL->buf,ERROR);
      return NIL;
    case EINVAL:
      if (pc) return (*pc) (stream,sequence,mailbox,options);
      sprintf (LOCAL->buf,"Invalid MBX-format mailbox name: %.80s",mailbox);
      mm_log (LOCAL->buf,ERROR);
      return NIL;
    default:
      if (pc) return (*pc) (stream,sequence,mailbox,options);
      sprintf (LOCAL->buf,"Not a MBX-format mailbox: %.80s",mailbox);
      mm_log (LOCAL->buf,ERROR);
      return NIL;
    }
				/* got file? */  
  if ((fd = open (dummy_file (file,mailbox),O_RDWR|O_CREAT|O_BINARY,
		  S_IREAD|S_IWRITE)) < 0) {
    sprintf (LOCAL->buf,"Unable to open copy mailbox: %s",strerror (errno));
    mm_log (LOCAL->buf,ERROR);
    return NIL;
  }
  mm_critical (stream);		/* go critical */
  fstat (fd,&sbuf);		/* get current file size */
  lseek (fd,sbuf.st_size,L_SET);/* move to end of file */

				/* for each requested message */
  for (i = 1; ret && (i <= stream->nmsgs); i++) 
    if ((elt = mail_elt (stream,i))->sequence) {
      lseek (LOCAL->fd,elt->private.special.offset +
	     elt->private.special.text.size,L_SET);
      mail_date(LOCAL->buf,elt);/* build target header */
				/* get target keyword mask */
      for (j = elt->user_flags, k = 0; j; )
	if (s = stream->user_flags[find_rightmost_bit (&j)])
	  for (m = 0; (m < NUSERFLAGS) && (t = dstream->user_flags[m]); m++)
	    if (!compare_cstring (s,t) && (k |= 1 << m)) break;
      sprintf (LOCAL->buf+strlen(LOCAL->buf),",%lu;%08lx%04x-%08lx\015\012",
	       elt->rfc822_size,k,(unsigned)
	       ((fSEEN * elt->seen) + (fDELETED * elt->deleted) +
		(fFLAGGED * elt->flagged) + (fANSWERED * elt->answered) +
		(fDRAFT * elt->draft)),cu ? ++dstream->uid_last : 0);
				/* write target header */
      if (ret = (write (fd,LOCAL->buf,strlen (LOCAL->buf)) > 0)) {
	for (k = elt->rfc822_size; ret && (j = min (k,LOCAL->buflen)); k -= j){
	  read (LOCAL->fd,LOCAL->buf,j);
	  ret = write (fd,LOCAL->buf,j) >= 0;
	}
	if (cu) {		/* need to pass back new UID? */
	  mail_append_set (source,mail_uid (stream,i));
	  mail_append_set (dest,dstream->uid_last);
	}
      }
    }

				/* make sure all the updates take */
  if (!(ret && (ret = !fsync (fd)))) {
    sprintf (LOCAL->buf,"Unable to write message: %s",strerror (errno));
    mm_log (LOCAL->buf,ERROR);
    ftruncate (fd,sbuf.st_size);
  }
  if (cu && ret) {		/* return sets if doing COPYUID */
    (*cu) (stream,mailbox,dstream->uid_validity,source,dest);
    lseek (fd,15,L_SET);	/* update UIDLAST */
    sprintf (LOCAL->buf,"%08lx",dstream->uid_last);
    write (fd,LOCAL->buf,8);
  }
  else {			/* flush any sets we may have built */
    mail_free_searchset (&source);
    mail_free_searchset (&dest);
  }
				/* set atime to now-1 if successful copy */
  if (ret) times.actime = time (0) - 1;
				/* else preserved \Marked status */
  else times.actime = (sbuf.st_ctime > sbuf.st_atime) ?
	 sbuf.st_atime : time (0);
  times.modtime = sbuf.st_mtime;/* preserve mtime */
  utime (file,&times);		/* set the times */
  close (fd);			/* close the file */
  mm_nocritical (stream);	/* release critical */
  unlockfd (ld,lock);		/* release exclusive parse/append permission */
				/* delete all requested messages */
  if (ret && (options & CP_MOVE) && mbx_flaglock (stream)) {
    for (i = 1; i <= stream->nmsgs; i++) if (mail_elt (stream,i)->sequence) {
				/* mark message deleted */
      mbx_elt (stream,i,NIL)->deleted = T;
				/* recalculate status */
      mbx_update_status (stream,i,NIL);
    }
				/* update flags */
    mbx_flag (stream,NIL,NIL,NIL);
  }
  if (dstream != stream) mail_close (dstream);
  return ret;
}

/* MBX mail append message from stringstruct
 * Accepts: MAIL stream
 *	    destination mailbox
 *	    append callback
 *	    data for callback
 * Returns: T if append successful, else NIL
 */

long mbx_append (MAILSTREAM *stream,char *mailbox,append_t af,void *data)
{
  struct stat sbuf;
  int fd,ld;
  char *flags,*date,tmp[MAILTMPLEN],file[MAILTMPLEN],lock[MAILTMPLEN];
  struct utimbuf times;
  FILE *df;
  MESSAGECACHE elt;
  long f;
  unsigned long i,uf;
  STRING *message;
  long ret = NIL;
  MAILSTREAM *dstream = NIL;
  appenduid_t au = (appenduid_t) mail_parameters (NIL,GET_APPENDUID,NIL);
  SEARCHSET *dst = au ? mail_newsearchset () : NIL;
				/* make sure valid mailbox */
				/* 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 : &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 (!(*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 || !(*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);
    if (ret) times.actime = time (0) - 1;
				/* else preserve \Marked status */
    else times.actime = (sbuf.st_ctime > sbuf.st_atime) ?
	   sbuf.st_atime : time (0);
				/* preserve mtime */
    times.modtime = sbuf.st_mtime;
    utime (file,&times);	/* 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 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 */

  stream->silent = T;		/* don't pass up mm_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 = (unsigned long) 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;