mbxnt.c

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 * Accepts: MAIL stream
 *	    old mailbox name
 *	    new mailbox name (or NIL for delete)
 * Returns: T on success, NIL on failure
 */

long mbx_rename (MAILSTREAM *stream,char *old,char *newname)
{
  long ret = LONGT;
  char c,*s,tmp[MAILTMPLEN],file[MAILTMPLEN],lock[MAILTMPLEN];
  int fd,ld;
  struct stat sbuf;
  if (!dummy_file (file,old) ||
      (newname && (!((s = mailboxfile (tmp,newname)) && *s) ||
		   ((s = strrchr (tmp,'\\')) && !s[1])))) {
    sprintf (tmp,newname ?
	     "Can't rename mailbox %.80s to %.80s: invalid name" :
	     "Can't delete mailbox %.80s: invalid name",
	     old,newname);
    mm_log (tmp,ERROR);
    return NIL;
  }
  else if ((fd = open (file,O_RDWR|O_BINARY,NIL)) < 0) {
    sprintf (tmp,"Can't open mailbox %.80s: %s",old,strerror (errno));
    mm_log (tmp,ERROR);
    return NIL;
  }
				/* get parse/append permission */
  if ((ld = lockname (lock,file,LOCK_EX)) < 0) {
    mm_log ("Unable to lock rename mailbox",ERROR);
    return NIL;
  }
				/* lock out other users */
  if (flock (fd,LOCK_EX|LOCK_NB)) {
    close (fd);			/* couldn't lock, give up on it then */
    sprintf (tmp,"Mailbox %.80s is in use by another process",old);
    mm_log (tmp,ERROR);
    unlockfd (ld,lock);		/* release exclusive parse/append permission */
    return NIL;
  }

  if (newname) {		/* want rename? */
				/* found superior to destination name? */
    if ((s = strrchr (tmp,'\\')) && (s != tmp) &&
	((tmp[1] != ':') || (s != tmp + 2))) {
      c = s[1];			/* remember character after delimiter */
      *s = s[1] = '\0';		/* tie off name at delimiter */
				/* name doesn't exist, create it */
      if (stat (tmp,&sbuf) || ((sbuf.st_mode & S_IFMT) != S_IFDIR)) {
	*s = '\\';		/* restore delimiter */
	if (!dummy_create (stream,tmp)) ret = NIL;
      }
      else *s = '\\';		/* restore delimiter */
      s[1] = c;			/* restore character after delimiter */
    }
    flock (fd,LOCK_UN);		/* release lock on the file */
    close (fd);			/* pacify NTFS */
				/* rename the file */
    if (ret && rename (file,tmp)) {
      sprintf (tmp,"Can't rename mailbox %.80s to %.80s: %s",old,newname,
	       strerror (errno));
      mm_log (tmp,ERROR);
      ret = NIL;		/* set failure */
    }
  }
  else {
    flock (fd,LOCK_UN);		/* release lock on the file */
    close (fd);			/* pacify NTFS */
    if (unlink (file)) {
      sprintf (tmp,"Can't delete mailbox %.80s: %s",old,strerror (errno));
      mm_log (tmp,ERROR);
      ret = NIL;		/* set failure */
    }
  }
  unlockfd (ld,lock);		/* release exclusive parse/append permission */
				/* recreate file if renamed INBOX */
  if (ret && !compare_cstring (old,"INBOX")) mbx_create (NIL,"INBOX");
  return ret;			/* return success */
}

/* MBX mail open
 * Accepts: stream to open
 * Returns: stream on success, NIL on failure
 */

MAILSTREAM *mbx_open (MAILSTREAM *stream)
{
  int fd,ld;
  short silent;
  char tmp[MAILTMPLEN];
  if (!stream) return &mbxproto;/* return prototype for OP_PROTOTYPE call */
  if (stream->local) fatal ("mbx recycle stream");
				/* canonicalize the mailbox name */
  if (!dummy_file (tmp,stream->mailbox)) {
    sprintf (tmp,"Can't open - invalid name: %.80s",stream->mailbox);
    mm_log (tmp,ERROR);
  }
  if (stream->rdonly ||
      (fd = open (tmp,O_RDWR|O_BINARY,NIL)) < 0) {
    if ((fd = open (tmp,O_RDONLY|O_BINARY,NIL)) < 0) {
      sprintf (tmp,"Can't open mailbox: %s",strerror (errno));
      mm_log (tmp,ERROR);
      return NIL;
    }
    else if (!stream->rdonly) {	/* got it, but readonly */
      mm_log ("Can't get write access to mailbox, access is readonly",WARN);
      stream->rdonly = T;
    }
  }

  stream->local = memset (fs_get (sizeof (MBXLOCAL)),NIL,sizeof (MBXLOCAL));
  LOCAL->fd = fd;		/* bind the file */
  LOCAL->ld = -1;		/* no flaglock */
  LOCAL->buf = (char *) fs_get (CHUNKSIZE);
  LOCAL->buflen = CHUNKSIZE - 1;
				/* note if an INBOX or not */
  stream->inbox = !compare_cstring (stream->mailbox,"INBOX");
  fs_give ((void **) &stream->mailbox);
  stream->mailbox = cpystr (tmp);
				/* get parse/append permission */
  if ((ld = lockname (tmp,stream->mailbox,LOCK_EX)) < 0) {
    mm_log ("Unable to lock open mailbox",ERROR);
    return NIL;
  }
  flock (LOCAL->fd,LOCK_SH);	/* lock the file */
  unlockfd (ld,tmp);		/* release shared parse permission */
  LOCAL->filesize = HDRSIZE;	/* initialize parsed file size */
  LOCAL->filetime = 0;		/* time not set up yet */
  LOCAL->expok = LOCAL->flagcheck = NIL;
  stream->sequence++;		/* bump sequence number */
				/* parse mailbox */
  stream->nmsgs = stream->recent = 0;
  silent = stream->silent;	/* defer events */
  stream->silent = T;
  if (mbx_ping (stream) && !stream->nmsgs)
    mm_log ("Mailbox is empty",(long) NIL);
  stream->silent = silent;	/* now notify upper level */
  mail_exists (stream,stream->nmsgs);
  mail_recent (stream,stream->recent);
  if (!LOCAL) return NIL;	/* failure if stream died */
  stream->perm_seen = stream->perm_deleted = stream->perm_flagged =
    stream->perm_answered = stream->perm_draft = stream->rdonly ? NIL : T;
  stream->perm_user_flags = stream->rdonly ? NIL : 0xffffffff;
  stream->kwd_create = (stream->user_flags[NUSERFLAGS-1] || stream->rdonly) ?
    NIL : T;			/* can we create new user flags? */
  return stream;		/* return stream to caller */
}

/* MBX mail close
 * Accepts: MAIL stream
 *	    close options
 */

void mbx_close (MAILSTREAM *stream,long options)
{
  if (stream && LOCAL) {	/* only if a file is open */
    int silent = stream->silent;
    stream->silent = T;		/* note this stream is dying */
				/* do an expunge if requested */
    if (options & CL_EXPUNGE) mbx_expunge (stream,NIL,NIL);
    else {			/* otherwise do a checkpoint to purge */
      LOCAL->expok = T;		/*  possible expunged messages */
      mbx_ping (stream);
    }
    stream->silent = silent;	/* restore previous status */
    mbx_abort (stream);
  }
}


/* MBX mail abort stream
 * Accepts: MAIL stream
 */

void mbx_abort (MAILSTREAM *stream)
{
  if (stream && LOCAL) {	/* only if a file is open */
    flock (LOCAL->fd,LOCK_UN);	/* unlock local file */
    close (LOCAL->fd);		/* close the local file */
				/* free local text buffer */
    if (LOCAL->buf) fs_give ((void **) &LOCAL->buf);
				/* nuke the local data */
    fs_give ((void **) &stream->local);
    stream->dtb = NIL;		/* log out the DTB */
  }
}


/* MBX mail fetch flags
 * Accepts: MAIL stream
 *	    sequence
 *	    option flags
 * Sniffs at file to see if some other process changed the flags
 */

void mbx_flags (MAILSTREAM *stream,char *sequence,long flags)
{
  MESSAGECACHE *elt;
  unsigned long i;
  if (mbx_ping (stream) &&	/* ping mailbox, get new status for messages */
      ((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)
	mbx_elt (stream,i,NIL);
}

/* MBX mail fetch message header
 * Accepts: MAIL stream
 *	    message # to fetch
 *	    pointer to returned header text length
 *	    option flags
 * Returns: message header in RFC822 format
 */

char *mbx_header (MAILSTREAM *stream,unsigned long msgno,unsigned long *length,
		  long flags)
{
  unsigned long i;
  char *s;
  *length = 0;			/* default to empty */
  if (flags & FT_UID) return "";/* UID call "impossible" */
				/* get header position, possibly header */
  i = mbx_hdrpos (stream,msgno,length,&s);
  if (!s) {			/* mbx_hdrpos() returned header? */
    lseek (LOCAL->fd,i,L_SET);	/* no, get to header position */
				/* is buffer big enough? */
    if (*length > LOCAL->buflen) {
      fs_give ((void **) &LOCAL->buf);
      LOCAL->buf = (char *) fs_get ((LOCAL->buflen = *length) + 1);
    }
				/* slurp the data */
    read (LOCAL->fd,s = LOCAL->buf,*length);
  }
  s[*length] = '\0';		/* tie off string */
  return s;
}

/* MBX mail fetch message text (body only)
 * Accepts: MAIL stream
 *	    message # to fetch
 *	    pointer to returned header text length
 *	    option flags
 * Returns: T on success, NIL on failure
 */

long mbx_text (MAILSTREAM *stream,unsigned long msgno,STRING *bs,long flags)
{
  FDDATA d;
  unsigned long i,j;
  MESSAGECACHE *elt;
				/* UID call "impossible" */
  if (flags & FT_UID) return NIL;
				/* get message status */
  elt = mbx_elt (stream,msgno,NIL);
				/* if message not seen */
  if (!(flags & FT_PEEK) && !elt->seen && mbx_flaglock (stream)) {
    elt->seen = T;		/* mark message as seen */
				/* recalculate status */
    mbx_update_status (stream,msgno,NIL);
    mm_flags (stream,msgno);
				/* update flags */
    mbx_flag (stream,NIL,NIL,NIL);
  }
  if (!LOCAL) return NIL;	/* mbx_flaglock() could have aborted */
				/* find header position */
  i = mbx_hdrpos (stream,msgno,&j,NIL);
  d.fd = LOCAL->fd;		/* set up file descriptor */
  d.pos = i + j;
  d.chunk = LOCAL->buf;	/* initial buffer chunk */
  d.chunksize = CHUNKSIZE;
  INIT (bs,fd_string,&d,elt->rfc822_size - j);
  return LONGT;			/* success */
}

/* MBX mail modify flags
 * Accepts: MAIL stream
 *	    sequence
 *	    flag(s)
 *	    option flags
 * Unlocks flag lock
 */

void mbx_flag (MAILSTREAM *stream,char *sequence,char *flag,long flags)
{
  struct utimbuf times;
  struct stat sbuf;
				/* make sure the update takes */
  if (!stream->rdonly && LOCAL && (LOCAL->fd >= 0) && (LOCAL->ld >= 0)) {
    fsync (LOCAL->fd);
    fstat (LOCAL->fd,&sbuf);	/* get current write time */
    times.modtime = LOCAL->filetime = sbuf.st_mtime;
				/* update header */
    if ((LOCAL->ffuserflag < NUSERFLAGS) &&
	stream->user_flags[LOCAL->ffuserflag]) mbx_update_header (stream);
    times.actime = time (0);	/* make sure read comes after all that */
    utime (stream->mailbox,&times);
  }
  if (LOCAL->ld >= 0) {		/* unlock now */
    unlockfd (LOCAL->ld,LOCAL->lock);
    LOCAL->ld = -1;
  }
}


/* MBX mail per-message modify flags
 * Accepts: MAIL stream
 *	    message cache element
 */

void mbx_flagmsg (MAILSTREAM *stream,MESSAGECACHE *elt)
{
  if (mbx_flaglock (stream)) mbx_update_status (stream,elt->msgno,NIL);
}

/* MBX mail ping mailbox
 * Accepts: MAIL stream
 * Returns: T if stream still alive, NIL if not
 */

long mbx_ping (MAILSTREAM *stream)
{
  unsigned long i,pos;
  long ret = NIL;
  int ld;
  char lock[MAILTMPLEN];
  MESSAGECACHE *elt;
  struct stat sbuf;
  if (stream && LOCAL) {	/* only if stream already open */
    ret = LONGT;		/* assume OK */
    fstat (LOCAL->fd,&sbuf);	/* get current file poop */
				/* allow expunge if permitted at ping */
    if (mail_parameters (NIL,GET_EXPUNGEATPING,NIL)) LOCAL->expok = T;
				/* if external modification */
    if (LOCAL->filetime && (LOCAL->filetime < sbuf.st_mtime))
      LOCAL->flagcheck = T;	/* upgrade to flag checking */
				/* new mail or flagcheck handling needed? */
    if (((sbuf.st_size - LOCAL->filesize) || LOCAL->flagcheck ||
	 !stream->nmsgs) &&
	((ld = lockname (lock,stream->mailbox,LOCK_EX)) >= 0)) {
      if (!LOCAL->flagcheck) ret = mbx_parse (stream);
				/* sweep mailbox for changed message status */
      else if (ret = mbx_parse (stream)) {
	unsigned long recent = 0;
	LOCAL->filetime = sbuf.st_mtime;
	for (i = 1; i <= stream->nmsgs; )
	  if (elt = mbx_elt (stream,i,LOCAL->expok)) {
	    if (elt->recent) ++recent;
	    ++i;
	  }
	mail_recent (stream,recent);
	LOCAL->flagcheck = NIL;	/* got all the updates */
      }
      unlockfd (ld,lock);	/* release shared parse/append permission */
    }
    if (ret) {			/* must still be alive */
      if (!LOCAL->expunged)	/* look for holes if none known yet */
	for (i = 1, pos = HDRSIZE;
	     !LOCAL->expunged && (i <= stream->nmsgs);
	     i++, pos += elt->private.special.text.size + elt->rfc822_size)
	  if ((elt = mail_elt (stream,i))->private.special.offset != pos)
	    LOCAL->expunged = T;/* found a hole */
				/* burp any holes */
      if (LOCAL->expunged && !stream->rdonly) {
	if (mbx_rewrite (stream,&i,NIL)) fatal ("expunge on check");
	if (i) {		/* any space reclaimed? */
	  LOCAL->expunged = NIL;/* no more pending expunge */
	  sprintf (LOCAL->buf,"Reclaimed %lu bytes of expunged space",i);
	  mm_log (LOCAL->buf,(long) NIL);
	}
      }
      LOCAL->expok = NIL;	/* no more expok */
    }
  }
  return ret;			/* return result of the parse */
}

/* MBX mail check mailbox (reparses status too)
 * Accepts: MAIL stream
 */

void mbx_check (MAILSTREAM *stream)
{
  if (LOCAL) LOCAL->expok = T;	/* mark that a check is desired */
  if (mbx_ping (stream)) mm_log ("Check completed",(long) NIL);
}


/* MBX mail expunge mailbox
 * Accepts: MAIL stream
 *	    sequence to expunge if non-NIL
 *	    expunge options
 * Returns: T if success, NIL if failure
 */

long mbx_expunge (MAILSTREAM *stream,char *sequence,long options)
{
  long ret;
  unsigned long nexp,reclaimed;
  if (ret = sequence ? ((options & EX_UID) ?
			mail_uid_sequence (stream,sequence) :
			mail_sequence (stream,sequence)) : LONGT) {
    if (!mbx_ping (stream));	/* do nothing if stream dead */
    else if (stream->rdonly)	/* won't do on readonly files! */
      mm_log ("Expunge ignored on readonly mailbox",WARN);
				/* if expunged any messages */
    else if (nexp = mbx_rewrite (stream,&reclaimed,sequence ? -1 : 1)) {
      sprintf (LOCAL->buf,"Expunged %lu messages",nexp);
      mm_log (LOCAL->buf,(long) NIL);
    }
    else if (reclaimed) {	 /* or if any prior expunged space reclaimed */
      sprintf (LOCAL->buf,"Reclaimed %lu bytes of expunged space",reclaimed);
      mm_log (LOCAL->buf,(long) NIL);
    }
    else mm_log ("No messages deleted, so no update needed",(long) NIL);
  }
  return ret;
}

/* MBX mail copy message(s)
 * Accepts: MAIL stream
 *	    sequence
 *	    destination mailbox
 *	    copy options