mx.c

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	}
				/* note uncached */
	LOCAL->cachedtexts -= ((elt->private.msg.header.text.data ?
				elt->private.msg.header.text.size : 0) +
			       (elt->private.msg.text.text.data ?
				elt->private.msg.text.text.size : 0));
	mail_gc_msg (&elt->private.msg,GC_ENV | GC_TEXTS);
	if(elt->recent)--recent;/* if recent, note one less recent message */
	mail_expunged(stream,i);/* notify upper levels */
	n++;			/* count up one more expunged message */
      }
      else i++;			/* otherwise try next message */
    }
    if (n) {			/* output the news if any expunged */
      sprintf (LOCAL->buf,"Expunged %lu messages",n);
      MM_LOG (LOCAL->buf,(long) NIL);
    }
    else MM_LOG ("No messages deleted, so no update needed",(long) NIL);
    MM_NOCRITICAL (stream);	/* release critical */
    mx_unlockindex (stream);	/* finished with index */
				/* notify upper level of new mailbox size */
    mail_exists (stream,stream->nmsgs);
    mail_recent (stream,recent);
  }
  return ret;
}

/* MX mail copy message(s)
 * Accepts: MAIL stream
 *	    sequence
 *	    destination mailbox
 *	    copy options
 * Returns: T if copy successful, else NIL
 */

long mx_copy (MAILSTREAM *stream,char *sequence,char *mailbox,long options)
{
  FDDATA d;
  STRING st;
  MESSAGECACHE *elt;
  MAILSTREAM *astream;
  struct stat sbuf;
  int fd;
  unsigned long i,j,uid,uidv;
  char *t,tmp[MAILTMPLEN];
  long ret;
  mailproxycopy_t pc =
    (mailproxycopy_t) mail_parameters (stream,GET_MAILPROXYCOPY,NIL);
				/* make sure valid mailbox */
  if (!mx_valid (mailbox)) switch (errno) {
  case NIL:			/* no error in stat() */
    if (pc) return (*pc) (stream,sequence,mailbox,options);
    sprintf (LOCAL->buf,"Not a MX-format mailbox: %.80s",mailbox);
    MM_LOG (LOCAL->buf,ERROR);
    return NIL;
  default:			/* some stat() error */
    MM_NOTIFY (stream,"[TRYCREATE] Must create mailbox before copy",NIL);
    return NIL;
  }
				/* copy the messages */
  if (!(ret = ((options & CP_UID) ? mail_uid_sequence (stream,sequence) :
	       mail_sequence (stream,sequence))));
				/* acquire stream to append to */
  else if (!(astream = mail_open (NIL,mailbox,OP_SILENT))) {
    MM_LOG ("Can't open copy mailbox",ERROR);
    ret = NIL;
  }
  else {
    MM_CRITICAL (stream);	/* go critical */
    if (!(ret = mx_lockindex (astream)))
      MM_LOG ("Message copy failed: unable to lock index",ERROR);
    else {

      copyuid_t cu = (copyuid_t) mail_parameters (NIL,GET_COPYUID,NIL);
      SEARCHSET *source = cu ? mail_newsearchset () : NIL;
      SEARCHSET *dest = cu ? mail_newsearchset () : NIL;
      for (i = 1,uid = uidv = 0; ret && (i <= stream->nmsgs); i++) 
      if ((elt = mail_elt (stream,i))->sequence) {
	if (ret = ((fd = open (mx_fast_work (stream,elt),O_RDONLY,NIL))
		   >= 0)) {
	  fstat (fd,&sbuf);	/* get size of message */
	  d.fd = fd;		/* set up file descriptor */
	  d.pos = 0;		/* start of file */
	  d.chunk = LOCAL->buf;
	  d.chunksize = CHUNKSIZE;
	  INIT (&st,fd_string,&d,sbuf.st_size);
				/* init flag string */
	  tmp[0] = tmp[1] = '\0';
	  if (j = elt->user_flags) do
	    if (t = stream->user_flags[find_rightmost_bit (&j)])
	      strcat (strcat (tmp," "),t);
	  while (j);
	  if (elt->seen) strcat (tmp," \\Seen");
	  if (elt->deleted) strcat (tmp," \\Deleted");
	  if (elt->flagged) strcat (tmp," \\Flagged");
	  if (elt->answered) strcat (tmp," \\Answered");
	  if (elt->draft) strcat (tmp," \\Draft");
	  tmp[0] = '(';		/* open list */
	  strcat (tmp,")");	/* close list */
	  if (ret = mx_append_msg (astream,tmp,elt,&st,dest)) {
				/* add to source set if needed */
	    if (source) mail_append_set (source,mail_uid (stream,i));
				/* delete if doing a move */
	    if (options & CP_MOVE) elt->deleted = T;
	  }
	}
      }
				/* return sets if doing COPYUID */
      if (cu && ret) (*cu) (stream,mailbox,astream->uid_validity,source,dest);
      else {			/* flush any sets we may have built */
	mail_free_searchset (&source);
	mail_free_searchset (&dest);
      }
      mx_unlockindex (astream);	/* unlock index */
    }
    MM_NOCRITICAL (stream);
    mail_close (astream);	/* finished with append stream */
  }
  return ret;			/* return success */
}

/* MX mail append message from stringstruct
 * Accepts: MAIL stream
 *	    destination mailbox
 *	    append callback
 *	    data for callback
 * Returns: T if append successful, else NIL
 */

long mx_append (MAILSTREAM *stream,char *mailbox,append_t af,void *data)
{
  MESSAGECACHE elt;
  MAILSTREAM *astream;
  char *flags,*date,tmp[MAILTMPLEN];
  STRING *message;
  long ret = LONGT;
				/* default stream to prototype */
  if (!stream) stream = user_flags (&mxproto);
				/* N.B.: can't use LOCAL->buf for tmp */
				/* make sure valid mailbox */
  if (!mx_isvalid (mailbox,tmp)) switch (errno) {
  case ENOENT:			/* no such file? */
    if (!compare_cstring (mailbox,"INBOX")) mx_create (NIL,"INBOX");
    else {
      MM_NOTIFY (stream,"[TRYCREATE] Must create mailbox before append",NIL);
      return NIL;
    }
				/* falls through */
  case 0:			/* merely empty file? */
    break;
  case EINVAL:
    sprintf (tmp,"Invalid MX-format mailbox name: %.80s",mailbox);
    MM_LOG (tmp,ERROR);
    return NIL;
  default:
    sprintf (tmp,"Not a MX-format mailbox: %.80s",mailbox);
    MM_LOG (tmp,ERROR);
    return NIL;
  }

				/* get first message */
  if (!MM_APPEND (af) (stream,data,&flags,&date,&message)) return NIL;
  if (!(astream = mail_open (NIL,mailbox,OP_SILENT))) {
    MM_LOG ("Can't open append mailbox",ERROR);
    return NIL;
  }
  MM_CRITICAL (astream);	/* go critical */
				/* lock the index */
  if (!(ret = mx_lockindex (astream)))
    MM_LOG ("Message append failed: unable to lock index",ERROR);
  else {
    appenduid_t au = (appenduid_t) mail_parameters (NIL,GET_APPENDUID,NIL);
    SEARCHSET *dst = au ? mail_newsearchset () : NIL;
    do {
				/* guard against zero-length */
      if (!(ret = SIZE (message)))
	MM_LOG ("Append of zero-length message",ERROR);
      else if (date && !(ret = mail_parse_date (&elt,date))) {
	sprintf (tmp,"Bad date in append: %.80s",date);
	MM_LOG (tmp,ERROR);
      }
      else ret = mx_append_msg (astream,flags,date ? &elt : NIL,message,dst)&&
	     MM_APPEND (af) (stream,data,&flags,&date,&message);
    } while (ret && message);
				/* return sets if doing APPENDUID */
    if (au && ret) (*au) (mailbox,astream->uid_validity,dst);
    else mail_free_searchset (&dst);
    mx_unlockindex (astream);	/* unlock index */
  }
  MM_NOCRITICAL (astream);	/* release critical */
  mail_close (astream);
  return ret;
}

/* MX mail append single message
 * Accepts: MAIL stream
 *	    flags for new message if non-NIL
 *	    elt with source date if non-NIL
 *	    stringstruct of message text
 *	    searchset to place UID
 * Returns: T if success, NIL if failure
 */

long mx_append_msg (MAILSTREAM *stream,char *flags,MESSAGECACHE *elt,
		    STRING *st,SEARCHSET *set)
{
  char tmp[MAILTMPLEN];
  int fd;
  unsigned long uf;
  long f = mail_parse_flags (stream,flags,&uf);
				/* make message file name */
  sprintf (tmp,"%s/%lu",stream->mailbox,++stream->uid_last);
  if ((fd = open (tmp,O_WRONLY|O_CREAT|O_EXCL,
		  (long) mail_parameters (NIL,GET_MBXPROTECTION,NIL))) < 0) {
    sprintf (tmp,"Can't create append message: %s",strerror (errno));
    MM_LOG (tmp,ERROR);
    return NIL;
  }
  while (SIZE (st)) {		/* copy the file */
    if (st->cursize && (write (fd,st->curpos,st->cursize) < 0)) {
      unlink (tmp);		/* delete file */
      close (fd);		/* close the file */
      sprintf (tmp,"Message append failed: %s",strerror (errno));
      MM_LOG (tmp,ERROR);
      return NIL;
    }
    SETPOS (st,GETPOS (st) + st->cursize);
  }
  close (fd);			/* close the file */
  if (elt) mx_setdate (tmp,elt);/* set file date */
				/* swell the cache */
  mail_exists (stream,++stream->nmsgs);
				/* copy flags */
  mail_append_set (set,(elt = mail_elt (stream,stream->nmsgs))->private.uid =
		   stream->uid_last);
  if (f&fSEEN) elt->seen = T;
  if (f&fDELETED) elt->deleted = T;
  if (f&fFLAGGED) elt->flagged = T;
  if (f&fANSWERED) elt->answered = T;
  if (f&fDRAFT) elt->draft = T;
  elt->user_flags |= uf;
  return LONGT;
}

/* Internal routines */


/* MX file name selection test
 * Accepts: candidate directory entry
 * Returns: T to use file name, NIL to skip it
 */

int mx_select (struct direct *name)
{
  char c;
  char *s = name->d_name;
  while (c = *s++) if (!isdigit (c)) return NIL;
  return T;
}


/* MX file name comparision
 * Accepts: first candidate directory entry
 *	    second candidate directory entry
 * Returns: negative if d1 < d2, 0 if d1 == d2, postive if d1 > d2
 */

int mx_numsort (const void *d1,const void *d2)
{
  return atoi ((*(struct direct **) d1)->d_name) -
    atoi ((*(struct direct **) d2)->d_name);
}


/* MX mail build file name
 * Accepts: destination string
 *          source
 * Returns: destination
 */

char *mx_file (char *dst,char *name)
{
  char *s;
				/* empty string if mailboxfile fails */
  if (!mailboxfile (dst,name)) *dst = '\0';
				/* driver-selected INBOX  */
  else if (!*dst) mailboxfile (dst,"~/INBOX");
				/* tie off unnecessary trailing / */
  else if ((s = strrchr (dst,'/')) && !s[1]) *s = '\0';
  return dst;
}

/* MX read and lock index
 * Accepts: MAIL stream
 * Returns: T if success, NIL if failure
 */

long mx_lockindex (MAILSTREAM *stream)
{
  unsigned long uf,sf,uid;
  int k = 0;
  unsigned long msgno = 1;
  struct stat sbuf;
  char *s,*t,*idx,tmp[2*MAILTMPLEN];
  MESSAGECACHE *elt;
  blocknotify_t bn = (blocknotify_t) mail_parameters (NIL,GET_BLOCKNOTIFY,NIL);
  if ((LOCAL->fd < 0) &&	/* get index file, no-op if already have it */
      (LOCAL->fd = open (strcat (strcpy (tmp,stream->mailbox),MXINDEXNAME),
			 O_RDWR|O_CREAT,
			 (long) mail_parameters (NIL,GET_MBXPROTECTION,NIL)))
      >= 0) {
    (*bn) (BLOCK_FILELOCK,NIL);
    flock (LOCAL->fd,LOCK_EX);	/* get exclusive lock */
    (*bn) (BLOCK_NONE,NIL);
    fstat (LOCAL->fd,&sbuf);	/* get size of index */
				/* slurp index */
    read (LOCAL->fd,s = idx = (char *) fs_get (sbuf.st_size + 1),sbuf.st_size);
    idx[sbuf.st_size] = '\0';	/* tie off index */
				/* parse index */
    if (sbuf.st_size) while (s && *s) switch (*s) {
    case 'V':			/* UID validity record */
      stream->uid_validity = strtoul (s+1,&s,16);
      break;
    case 'L':			/* UID last record */
      stream->uid_last = strtoul (s+1,&s,16);
      break;
    case 'K':			/* keyword */
				/* find end of keyword */
      if (s = strchr (t = ++s,'\n')) {
	*s++ = '\0';		/* tie off keyword */
				/* copy keyword */
	if ((k < NUSERFLAGS) && !stream->user_flags[k] &&
	    (strlen (t) <= MAXUSERFLAG)) stream->user_flags[k] = cpystr (t);
	k++;			/* one more keyword */
      }
      break;

    case 'M':			/* message status record */
      uid = strtoul (s+1,&s,16);/* get UID for this message */
      if (*s == ';') {		/* get user flags */
	uf = strtoul (s+1,&s,16);
	if (*s == '.') {	/* get system flags */
	  sf = strtoul (s+1,&s,16);
	  while ((msgno <= stream->nmsgs) && (mail_uid (stream,msgno) < uid))
	    msgno++;		/* find message number for this UID */
	  if ((msgno <= stream->nmsgs) && (mail_uid (stream,msgno) == uid)) {
	    (elt = mail_elt (stream,msgno))->valid = T;
	    elt->user_flags=uf; /* set user and system flags in elt */
	    if (sf & fSEEN) elt->seen = T;
	    if (sf & fDELETED) elt->deleted = T;
	    if (sf & fFLAGGED) elt->flagged = T;
	    if (sf & fANSWERED) elt->answered = T;
	    if (sf & fDRAFT) elt->draft = T;
	  }
	  break;
	}
      }
    default:			/* bad news */
      sprintf (tmp,"Error in index: %.80s",s);
      MM_LOG (tmp,ERROR);
      *s = NIL;			/* ignore remainder of index */
    }
    else {			/* new index */
      stream->uid_validity = time (0);
      user_flags (stream);	/* init stream with default user flags */
    }
    fs_give ((void **) &idx);	/* flush index */
  }
  return (LOCAL->fd >= 0) ? T : NIL;
}

/* MX write and unlock index
 * Accepts: MAIL stream
 */

#define MXIXBUFLEN 2048

void mx_unlockindex (MAILSTREAM *stream)
{
  unsigned long i,j;
  off_t size = 0;
  char *s,tmp[MXIXBUFLEN + 64];
  MESSAGECACHE *elt;
  if (LOCAL->fd >= 0) {
    lseek (LOCAL->fd,0,L_SET);	/* rewind file */
				/* write header */
    sprintf (s = tmp,"V%08lxL%08lx",stream->uid_validity,stream->uid_last);
    for (i = 0; (i < NUSERFLAGS) && stream->user_flags[i]; ++i)
      sprintf (s += strlen (s),"K%s\n",stream->user_flags[i]);
				/* write messages */
    for (i = 1; i <= stream->nmsgs; i++) {
				/* filled buffer? */
      if (((s += strlen (s)) - tmp) > MXIXBUFLEN) {
	write (LOCAL->fd,tmp,j = s - tmp);
	size += j;
	*(s = tmp) = '\0';	/* dump out and restart buffer */
      }
      elt = mail_elt (stream,i);
      sprintf(s,"M%08lx;%08lx.%04x",elt->private.uid,elt->user_flags,(unsigned)
	      ((fSEEN * elt->seen) + (fDELETED * elt->deleted) +
	       (fFLAGGED * elt->flagged) + (fANSWERED * elt->answered) +
	       (fDRAFT * elt->draft)));
    }
				/* write tail end of buffer */
    if ((s += strlen (s)) != tmp) {
      write (LOCAL->fd,tmp,j = s - tmp);
      size += j;
    }
    ftruncate (LOCAL->fd,size);
    flock (LOCAL->fd,LOCK_UN);	/* unlock the index */
    close (LOCAL->fd);		/* finished with file */
    LOCAL->fd = -1;		/* no index now */
  }
}

/* Set date for message
 * Accepts: file name
 *	    elt containing date
 */

void mx_setdate (char *file,MESSAGECACHE *elt)
{
  time_t tp[2];
  tp[0] = time (0);		/* atime is now */
  tp[1] = mail_longdate (elt);	/* modification time */
  utime (file,tp);		/* set the times */
}