unix.c

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				/* only after finishing */
  if (elt->valid) elt->private.dirty = LOCAL->dirty = T;
}


/* UNIX mail ping mailbox
 * Accepts: MAIL stream
 * Returns: T if stream alive, else NIL
 */

long unix_ping (MAILSTREAM *stream)
{
  DOTLOCK lock;
  struct stat sbuf;
  long reparse;
				/* big no-op if not readwrite */
  if (LOCAL && (LOCAL->ld >= 0) && !stream->lock) {
    if (stream->rdonly) {	/* does he want to give up readwrite? */
				/* checkpoint if we changed something */
      if (LOCAL->dirty) unix_check (stream);
      flock (LOCAL->ld,LOCK_UN);/* release readwrite lock */
      close (LOCAL->ld);	/* close the readwrite lock file */
      LOCAL->ld = -1;		/* no more readwrite lock fd */
      unlink (LOCAL->lname);	/* delete the readwrite lock file */
    }
    else {			/* see if need to reparse */
      if (!(reparse = (long) mail_parameters (NIL,GET_NETFSSTATBUG,NIL))) {
				/* get current mailbox size */
	if (LOCAL->fd >= 0) fstat (LOCAL->fd,&sbuf);
	else if (stat (stream->mailbox,&sbuf)) {
	  sprintf (LOCAL->buf,"Mailbox stat failed, aborted: %s",
		   strerror (errno));
	  MM_LOG (LOCAL->buf,ERROR);
	  unix_abort (stream);
	  return NIL;
	}
	reparse = (sbuf.st_size != LOCAL->filesize);
      }
				/* parse if mailbox changed */
      if ((LOCAL->ddirty || reparse) && unix_parse (stream,&lock,LOCK_EX)) {
				/* force checkpoint if double-dirty */
	if (LOCAL->ddirty) unix_rewrite (stream,NIL,&lock,NIL);
				/* unlock mailbox */
	else unix_unlock (LOCAL->fd,stream,&lock);
	mail_unlock (stream);	/* and stream */
	MM_NOCRITICAL (stream);	/* done with critical */
      }
    }
  }
  return LOCAL ? LONGT : NIL;	/* return if still alive */
}

/* UNIX mail check mailbox
 * Accepts: MAIL stream
 */

void unix_check (MAILSTREAM *stream)
{
  DOTLOCK lock;
				/* parse and lock mailbox */
  if (LOCAL && (LOCAL->ld >= 0) && !stream->lock &&
      unix_parse (stream,&lock,LOCK_EX)) {
				/* any unsaved changes? */
    if (LOCAL->dirty && unix_rewrite (stream,NIL,&lock,NIL)) {
      if (!stream->silent) MM_LOG ("Checkpoint completed",NIL);
    }
				/* no checkpoint needed, just unlock */
    else unix_unlock (LOCAL->fd,stream,&lock);
    mail_unlock (stream);	/* unlock the stream */
    MM_NOCRITICAL (stream);	/* done with critical */
  }
}


/* UNIX mail expunge mailbox
 * Accepts: MAIL stream
 *	    sequence to expunge if non-NIL
 *	    expunge options
 * Returns: T, always
 */

long unix_expunge (MAILSTREAM *stream,char *sequence,long options)
{
  long ret;
  unsigned long i;
  DOTLOCK lock;
  char *msg = NIL;
				/* parse and lock mailbox */
  if (ret = (sequence ? ((options & EX_UID) ?
			 mail_uid_sequence (stream,sequence) :
			 mail_sequence (stream,sequence)) : LONGT) &&
      LOCAL && (LOCAL->ld >= 0) && !stream->lock &&
      unix_parse (stream,&lock,LOCK_EX)) {
				/* check expunged messages if not dirty */
    for (i = 1; !LOCAL->dirty && (i <= stream->nmsgs); i++) {
      MESSAGECACHE *elt = mail_elt (stream,i);
      if (mail_elt (stream,i)->deleted) LOCAL->dirty = T;
    }
    if (!LOCAL->dirty) {	/* not dirty and no expunged messages */
      unix_unlock (LOCAL->fd,stream,&lock);
      msg = "No messages deleted, so no update needed";
    }
    else if (unix_rewrite (stream,&i,&lock,sequence ? LONGT : NIL)) {
      if (i) sprintf (msg = LOCAL->buf,"Expunged %lu messages",i);
      else msg = "Mailbox checkpointed, but no messages expunged";
    }
				/* rewrite failed */
    else unix_unlock (LOCAL->fd,stream,&lock);
    mail_unlock (stream);	/* unlock the stream */
    MM_NOCRITICAL (stream);	/* done with critical */
    if (msg && !stream->silent) MM_LOG (msg,NIL);
  }
  else if (!stream->silent) MM_LOG("Expunge ignored on readonly mailbox",WARN);
  return ret;
}

/* UNIX mail copy message(s)
 * Accepts: MAIL stream
 *	    sequence
 *	    destination mailbox
 *	    copy options
 * Returns: T if copy successful, else NIL
 */

long unix_copy (MAILSTREAM *stream,char *sequence,char *mailbox,long options)
{
  struct stat sbuf;
  int fd;
  char *s,file[MAILTMPLEN];
  DOTLOCK lock;
  time_t tp[2];
  unsigned long i,j;
  MESSAGECACHE *elt;
  long ret = T;
  mailproxycopy_t pc =
    (mailproxycopy_t) mail_parameters (stream,GET_MAILPROXYCOPY,NIL);
  copyuid_t cu = (copyuid_t) (mail_parameters (NIL,GET_USERHASNOLIFE,NIL) ?
			      NIL : mail_parameters (NIL,GET_COPYUID,NIL));
  SEARCHSET *source = cu ? mail_newsearchset () : NIL;
  SEARCHSET *dest = cu ? mail_newsearchset () : NIL;
  MAILSTREAM *tstream = NIL;
  DRIVER *d;
  for (d = (DRIVER *) mail_parameters (NIL,GET_DRIVERS,NIL);
       (d && strcmp (d->name,"mbox") && !(d->flags & DR_DISABLE));
       d = d->next);		/* see if mbox driver active */
  if (!((options & CP_UID) ? mail_uid_sequence (stream,sequence) :
	mail_sequence (stream,sequence))) return NIL;
				/* make sure destination is valid */
  if (!((d && mbox_valid (mailbox) && (mailbox = "mbox")) ||
	unix_valid (mailbox) || !errno))
    switch (errno) {
    case ENOENT:		/* no such file? */
      if (compare_cstring (mailbox,"INBOX")) {
	MM_NOTIFY (stream,"[TRYCREATE] Must create mailbox before copy",NIL);
	return NIL;
      }
      if (pc) return (*pc) (stream,sequence,mailbox,options);
      unix_create (NIL,"INBOX");/* create empty INBOX */
    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 UNIX-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 UNIX-format mailbox: %.80s",mailbox);
      MM_LOG (LOCAL->buf,ERROR);
      return NIL;
    }

				/* try to open rewrite for UIDPLUS */
  if ((tstream = mail_open_work (&unixdriver,NIL,mailbox,
				 OP_SILENT|OP_NOKOD)) && tstream->rdonly)
    tstream = mail_close (tstream);
  if (cu && !tstream) {		/* wanted a COPYUID? */
    sprintf (LOCAL->buf,"Unable to write-open mailbox for COPYUID: %.80s",
	     mailbox);
    MM_LOG (LOCAL->buf,WARN);
    cu = NIL;			/* don't try to do COPYUID */
  }
  LOCAL->buf[0] = '\0';
  MM_CRITICAL (stream);		/* go critical */
  if ((fd = unix_lock (dummy_file (file,mailbox),O_WRONLY|O_APPEND,
		       (long) mail_parameters (NIL,GET_MBXPROTECTION,NIL),
		       &lock,LOCK_EX)) < 0) {
    MM_NOCRITICAL (stream);	/* done with critical */
    sprintf (LOCAL->buf,"Can't open destination mailbox: %s",strerror (errno));
    MM_LOG (LOCAL->buf,ERROR);/* log the error */
    return NIL;			/* failed */
  }
  fstat (fd,&sbuf);		/* get current file size */
				/* write all requested messages to mailbox */
  for (i = 1; ret && (i <= stream->nmsgs); i++)
    if ((elt = mail_elt (stream,i))->sequence) {
      lseek (LOCAL->fd,elt->private.special.offset,L_SET);
      read (LOCAL->fd,LOCAL->buf,elt->private.special.text.size);
      if (write (fd,LOCAL->buf,elt->private.special.text.size) < 0) ret = NIL;
      else {			/* internal header succeeded */
	s = unix_header (stream,i,&j,FT_INTERNAL);
				/* header size, sans trailing newline */
	if (j && (s[j - 2] == '\n')) j--;
	if (write (fd,s,j) < 0) ret = NIL;
	else {			/* message header succeeded */
	  j = tstream ?		/* write UIDPLUS data if have readwrite */
	    unix_xstatus (stream,LOCAL->buf,elt,++(tstream->uid_last),LONGT) :
	    unix_xstatus (stream,LOCAL->buf,elt,NIL,NIL);
	  if (write (fd,LOCAL->buf,j) < 0) ret = NIL;
	  else {		/* message status succeeded */
	    s = unix_text_work (stream,elt,&j,FT_INTERNAL);
	    if ((write (fd,s,j) < 0) || (write (fd,"\n",1) < 0)) ret = NIL;
	    else if (cu) {	/* need to pass back new UID? */
	      mail_append_set (source,mail_uid (stream,i));
	      mail_append_set (dest,tstream->uid_last);
	    }
	  }
	}
      }
    }

  if (!ret || fsync (fd)) {	/* force out the update */
    sprintf (LOCAL->buf,"Message copy failed: %s",strerror (errno));
    ftruncate (fd,sbuf.st_size);
    ret = NIL;
  }
				/* force UIDVALIDITY assignment now */
  if (tstream && !tstream->uid_validity) tstream->uid_validity = time (0);
				/* return sets if doing COPYUID */
  if (cu && ret) (*cu) (stream,mailbox,tstream->uid_validity,source,dest);
  else {			/* flush any sets we may have built */
    mail_free_searchset (&source);
    mail_free_searchset (&dest);
  }
  tp[1] = time (0);		/* set mtime to now */
  if (ret) tp[0] = tp[1] - 1;	/* set atime to now-1 if successful copy */
  else tp[0] =			/* else preserve \Marked status */
	 ((sbuf.st_ctime > sbuf.st_atime) || (sbuf.st_mtime > sbuf.st_atime)) ?
	 sbuf.st_atime : tp[1];
  utime (file,tp);		/* set the times */
  unix_unlock (fd,NIL,&lock);	/* unlock and close mailbox */
  if (tstream) {		/* update last UID if we can */
    UNIXLOCAL *local = (UNIXLOCAL *) tstream->local;
    local->dirty = T;		/* do a rewrite */
    local->appending = T;	/* but not at the cost of marking as old */
    tstream = mail_close (tstream);
  }
				/* log the error */
  if (!ret) MM_LOG (LOCAL->buf,ERROR);
				/* delete if requested message */
  else if (options & CP_MOVE) for (i = 1; i <= stream->nmsgs; i++)
    if ((elt = mail_elt (stream,i))->sequence)
      elt->deleted = elt->private.dirty = LOCAL->dirty = T;
  MM_NOCRITICAL (stream);	/* release critical */
  return ret;
}

/* UNIX mail append message from stringstruct
 * Accepts: MAIL stream
 *	    destination mailbox
 *	    append callback
 *	    data for callback
 * Returns: T if append successful, else NIL
 */

#define BUFLEN 8*MAILTMPLEN

long unix_append (MAILSTREAM *stream,char *mailbox,append_t af,void *data)
{
  struct stat sbuf;
  int fd;
  unsigned long i;
  char *flags,*date,buf[BUFLEN],tmp[MAILTMPLEN],file[MAILTMPLEN];
  time_t tp[2];
  FILE *sf,*df;
  MESSAGECACHE elt;
  DOTLOCK lock;
  STRING *message;
  unsigned long uidlocation = 0;
  appenduid_t au = (appenduid_t)
    (mail_parameters (NIL,GET_USERHASNOLIFE,NIL) ? NIL :
     mail_parameters (NIL,GET_APPENDUID,NIL));
  SEARCHSET *dst = au ? mail_newsearchset () : NIL;
  long ret = LONGT;
  MAILSTREAM *tstream = NIL;
  if (!stream) {		/* stream specified? */
    stream = &unixproto;	/* no, default stream to prototype */
    for (i = 0; i < NUSERFLAGS && stream->user_flags[i]; ++i)
      fs_give ((void **) &stream->user_flags[i]);
  }
  if (!unix_valid (mailbox)) switch (errno) {
  case ENOENT:			/* no such file? */
    if (compare_cstring (mailbox,"INBOX")) {
      MM_NOTIFY (stream,"[TRYCREATE] Must create mailbox before append",NIL);
      return NIL;
    }
    unix_create (NIL,"INBOX");	/* create empty INBOX */
  case 0:			/* merely empty file? */
    tstream = stream;
    break;
  case EACCES:			/* file protected */
    sprintf (tmp,"Can't access destination: %.80s",mailbox);
    MM_LOG (tmp,ERROR);
    return NIL;
  case EINVAL:
    sprintf (tmp,"Invalid UNIX-format mailbox name: %.80s",mailbox);
    MM_LOG (tmp,ERROR);
    return NIL;
  default:
    sprintf (tmp,"Not a UNIX-format mailbox: %.80s",mailbox);
    MM_LOG (tmp,ERROR);
    return NIL;
  }
				/* get sniffing stream for keywords */
  else if (!(tstream = mail_open (NIL,mailbox,
				  OP_READONLY|OP_SILENT|OP_NOKOD|OP_SNIFF))) {
    sprintf (tmp,"Unable to examine mailbox for APPEND: %.80s",mailbox);
    MM_LOG (tmp,ERROR);
    return NIL;
  }

				/* get first message */
  if (!MM_APPEND (af) (tstream,data,&flags,&date,&message)) return NIL;
  if (!(sf = tmpfile ())) {	/* must have scratch file */
    sprintf (tmp,".%lx.%lx",(unsigned long) time (0),(unsigned long)getpid ());
    if (!stat (tmp,&sbuf) || !(sf = fopen (tmp,"wb+"))) {
      sprintf (tmp,"Unable to create scratch file: %.80s",strerror (errno));
      MM_LOG (tmp,ERROR);
      return NIL;
    }
    unlink (tmp);
  }
  do {				/* parse date */
    if (!date) rfc822_date (date = tmp);
    if (!mail_parse_date (&elt,date)) {
      sprintf (tmp,"Bad date in append: %.80s",date);
      MM_LOG (tmp,ERROR);
    }
    else {			/* user wants to suppress time zones? */
      if (mail_parameters (NIL,GET_NOTIMEZONES,NIL)) {
	time_t when = mail_longdate (&elt);
	date = ctime (&when);	/* use traditional date */
      }
				/* use POSIX-style date */
      else date = mail_cdate (tmp,&elt);
      if (!SIZE (message)) MM_LOG ("Append of zero-length message",ERROR);
      else if (!unix_collect_msg (tstream,sf,flags,date,message)) {
	sprintf (tmp,"Error writing scratch file: %.80s",strerror (errno));
	MM_LOG (tmp,ERROR);
      }
				/* get next message */
      else if (MM_APPEND (af) (tstream,data,&flags,&date,&message)) continue;
    }
    fclose (sf);		/* punt scratch file */
    return NIL;			/* give up */
  } while (message);		/* until no more messages */
  if (fflush (sf)) {
    sprintf (tmp,"Error finishing scratch file: %.80s",strerror (errno));
    MM_LOG (tmp,ERROR);
    fclose (sf);		/* punt scratch file */
    return NIL;			/* give up */
  }
  i = ftell (sf);		/* size of scratch file */
				/* close sniffing stream */
  if (tstream != stream) tstream = mail_close (tstream);

  MM_CRITICAL (stream);		/* go critical */
				/* try to open readwrite for UIDPLUS */
  if ((tstream = mail_open_work (&unixdriver,NIL,mailbox,
				 OP_SILENT|OP_NOKOD)) && tstream->rdonly)
    tstream = mail_close (tstream);
  if (au && !tstream) {		/* wanted an APPENDUID? */
    sprintf (tmp,"Unable to re-open mailbox for APPENDUID: %.80s",mailbox);
    MM_LOG (tmp,WARN);
    au = NIL;
  }