mh.c

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  cp = curdir + strlen (curdir);/* end of directory name */
  np = name + strlen (name);	/* end of MH name */
  if (dp = opendir (curdir)) {	/* open directory */
    while (d = readdir (dp))	/* scan, ignore . and numeric names */
      if ((d->d_name[0] != '.') && !mh_select (d)) {
	strcpy (cp,d->d_name);	/* make directory name */
	if (!stat (curdir,&sbuf) && ((sbuf.st_mode & S_IFMT) == S_IFDIR)) {
	  strcpy (np,d->d_name);/* make mh name of directory name */
				/* yes, an MH name if full match */
	  if (pmatch_full (name,pat,'/')) mm_list (stream,'/',name,NIL);
				/* check if should recurse */
	  if (dmatch (name,pat,'/') &&
	      (level < (long) mail_parameters (NIL,GET_LISTMAXLEVEL,NIL)))
	    mh_list_work (stream,name+4,pat,level+1);
	}
      }
    closedir (dp);		/* all done, flush directory */
  }
}

/* MH mail subscribe to mailbox
 * Accepts: mail stream
 *	    mailbox to add to subscription list
 * Returns: T on success, NIL on failure
 */

long mh_subscribe (MAILSTREAM *stream,char *mailbox)
{
  return sm_subscribe (mailbox);
}


/* MH mail unsubscribe to mailbox
 * Accepts: mail stream
 *	    mailbox to delete from subscription list
 * Returns: T on success, NIL on failure
 */

long mh_unsubscribe (MAILSTREAM *stream,char *mailbox)
{
  return sm_unsubscribe (mailbox);
}

/* MH mail create mailbox
 * Accepts: mail stream
 *	    mailbox name to create
 * Returns: T on success, NIL on failure
 */

long mh_create (MAILSTREAM *stream,char *mailbox)
{
  char tmp[MAILTMPLEN];
  if (!mh_namevalid (mailbox))	/* validate name */
    sprintf (tmp,"Can't create mailbox %.80s: invalid MH-format name",mailbox);
				/* must not already exist */
  else if (mh_isvalid (mailbox,tmp,NIL))
    sprintf (tmp,"Can't create mailbox %.80s: mailbox already exists",mailbox);
  else if (!mh_path (tmp)) return NIL;
				/* try to make it */
  else if (!(mh_file (tmp,mailbox) &&
	     dummy_create_path (stream,strcat (tmp,"/"),
				get_dir_protection (mailbox))))
    sprintf (tmp,"Can't create mailbox %.80s: %s",mailbox,strerror (errno));
  else return LONGT;		/* success */
  mm_log (tmp,ERROR);
  return NIL;
}

/* MH mail delete mailbox
 *	    mailbox name to delete
 * Returns: T on success, NIL on failure
 */

long mh_delete (MAILSTREAM *stream,char *mailbox)
{
  DIR *dirp;
  struct direct *d;
  int i;
  char tmp[MAILTMPLEN];
				/* is mailbox valid? */
  if (!mh_isvalid (mailbox,tmp,NIL)) {
    sprintf (tmp,"Can't delete mailbox %.80s: no such mailbox",mailbox);
    mm_log (tmp,ERROR);
    return NIL;
  }
				/* get name of directory */
  i = strlen (mh_file (tmp,mailbox));
  if (dirp = opendir (tmp)) {	/* open directory */
    tmp[i++] = '/';		/* now apply trailing delimiter */
				/* massacre all mh owned files */
    while (d = readdir (dirp)) if (mh_dirfmttest (d->d_name)) {
      strcpy (tmp + i,d->d_name);
      unlink (tmp);		/* sayonara */
    }
    closedir (dirp);		/* flush directory */
  }
				/* try to remove the directory */
  if (rmdir (mh_file (tmp,mailbox))) {
    sprintf (tmp,"Can't delete mailbox %.80s: %s",mailbox,strerror (errno));
    mm_log (tmp,WARN);
  }
  return T;			/* return success */
}

/* MH mail rename mailbox
 * Accepts: MH mail stream
 *	    old mailbox name
 *	    new mailbox name
 * Returns: T on success, NIL on failure
 */

long mh_rename (MAILSTREAM *stream,char *old,char *newname)
{
  char c,*s,tmp[MAILTMPLEN],tmp1[MAILTMPLEN];
  struct stat sbuf;
				/* old mailbox name must be valid */
  if (!mh_isvalid (old,tmp,NIL))
    sprintf (tmp,"Can't rename mailbox %.80s: no such mailbox",old);
  else if (!mh_namevalid (newname))
    sprintf (tmp,"Can't rename to mailbox %.80s: invalid MH-format name",
	     newname);
				/* new mailbox name must not be valid */
  else if (mh_isvalid (newname,tmp,NIL))
    sprintf (tmp,"Can't rename to mailbox %.80s: destination already exists",
	     newname);
				/* success if can rename the directory */
  else {			/* found superior to destination name? */
    if (s = strrchr (mh_file (tmp1,newname),'/')) {
      c = *++s;			/* remember first character of inferior */
      *s = '\0';		/* tie off to get just superior */
				/* name doesn't exist, create it */
      if ((stat (tmp1,&sbuf) || ((sbuf.st_mode & S_IFMT) != S_IFDIR)) &&
	  !dummy_create_path (stream,tmp1,get_dir_protection (newname)))
	return NIL;
      *s = c;			/* restore full name */
    }
    if (!rename (mh_file (tmp,old),tmp1)) return T;
    sprintf (tmp,"Can't rename mailbox %.80s to %.80s: %s",
	     old,newname,strerror (errno));
  }
  mm_log (tmp,ERROR);		/* something failed */
  return NIL;
}

/* MH mail open
 * Accepts: stream to open
 * Returns: stream on success, NIL on failure
 */

MAILSTREAM *mh_open (MAILSTREAM *stream)
{
  char tmp[MAILTMPLEN];
  if (!stream) return &mhproto;	/* return prototype for OP_PROTOTYPE call */
  if (stream->local) fatal ("mh recycle stream");
  stream->local = fs_get (sizeof (MHLOCAL));
  /* INBOXness is one of the following:
   * #mhinbox (case-independent)
   * #mh/inbox (mh is case-independent, inbox is case-dependent)
   * INBOX (case-independent
   */		
  stream->inbox =		/* note if an INBOX or not */
    (!compare_cstring (stream->mailbox,MHINBOX) ||
     ((stream->mailbox[0] == '#') &&
      ((stream->mailbox[1] == 'm') || (stream->mailbox[1] == 'M')) &&
      ((stream->mailbox[2] == 'h') || (stream->mailbox[2] == 'H')) &&
      (stream->mailbox[3] == '/') && !strcmp (stream->mailbox+4,MHINBOXDIR)) ||
     !compare_cstring (stream->mailbox,"INBOX")) ? T : NIL;
  mh_file (tmp,stream->mailbox);/* get directory name */
  LOCAL->dir = cpystr (tmp);	/* copy directory name for later */
  LOCAL->scantime = 0;		/* not scanned yet */
  LOCAL->cachedtexts = 0;	/* no cached texts */
  stream->sequence++;		/* bump sequence number */
				/* parse mailbox */
  stream->nmsgs = stream->recent = 0;
  if (!mh_ping (stream)) return NIL;
  if (!(stream->nmsgs || stream->silent))
    mm_log ("Mailbox is empty",(long) NIL);
  return stream;		/* return stream to caller */
}

/* MH mail close
 * Accepts: MAIL stream
 *	    close options
 */

void mh_close (MAILSTREAM *stream,long options)
{
  if (LOCAL) {			/* only if a file is open */
    int silent = stream->silent;
    stream->silent = T;		/* note this stream is dying */
    if (options & CL_EXPUNGE) mh_expunge (stream,NIL,NIL);
    if (LOCAL->dir) fs_give ((void **) &LOCAL->dir);
				/* nuke the local data */
    fs_give ((void **) &stream->local);
    stream->dtb = NIL;		/* log out the DTB */
    stream->silent = silent;	/* reset silent state */
  }
}


/* MH mail fetch fast information
 * Accepts: MAIL stream
 *	    sequence
 *	    option flags
 */

void mh_fast (MAILSTREAM *stream,char *sequence,long flags)
{
  MESSAGECACHE *elt;
  unsigned long i;
				/* set up metadata for all messages */
  if (stream && LOCAL && ((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->day && elt->rfc822_size)) mh_load_message (stream,i,NIL);
}

/* MH load message into cache
 * Accepts: MAIL stream
 *	    message #
 *	    option flags
 */

void mh_load_message (MAILSTREAM *stream,unsigned long msgno,long flags)
{
  unsigned long i,j,nlseen;
  int fd;
  unsigned char c,*t;
  struct stat sbuf;
  MESSAGECACHE *elt;
  FDDATA d;
  STRING bs;
  elt = mail_elt (stream,msgno);/* get elt */
				/* build message file name */
  sprintf (LOCAL->buf,"%s/%lu",LOCAL->dir,elt->private.uid);
				/* anything we need not currently cached? */
  if ((!elt->day || !elt->rfc822_size ||
       ((flags & MLM_HEADER) && !elt->private.msg.header.text.data) ||
       ((flags & MLM_TEXT) && !elt->private.msg.text.text.data)) &&
      ((fd = open (LOCAL->buf,O_RDONLY,NIL)) >= 0)) {
    fstat (fd,&sbuf);		/* get file metadata */
    d.fd = fd;			/* set up file descriptor */
    d.pos = 0;			/* start of file */
    d.chunk = LOCAL->buf;
    d.chunksize = CHUNKSIZE;
    INIT (&bs,fd_string,&d,sbuf.st_size);
    if (!elt->day) {		/* set internaldate to file date */
      struct tm *tm = gmtime (&sbuf.st_mtime);
      elt->day = tm->tm_mday; elt->month = tm->tm_mon + 1;
      elt->year = tm->tm_year + 1900 - BASEYEAR;
      elt->hours = tm->tm_hour; elt->minutes = tm->tm_min;
      elt->seconds = tm->tm_sec;
      elt->zhours = 0; elt->zminutes = 0;
    }

    if (!elt->rfc822_size) {	/* know message size yet? */
      for (i = 0, j = SIZE (&bs), nlseen = 0; j--; ) switch (SNX (&bs)) {
      case '\015':		/* unlikely carriage return */
	if (!j || (CHR (&bs) != '\012')) {
	  i++;			/* ugh, raw CR */
	  nlseen = NIL;
	  break;
	}
	SNX (&bs);		/* eat the line feed, drop in */
	--j;
      case '\012':		/* line feed? */
	i += 2;			/* count a CRLF */
				/* header size known yet? */
	if (!elt->private.msg.header.text.size && nlseen) {
				/* note position in file */
	  elt->private.special.text.size = GETPOS (&bs);
				/* and CRLF-adjusted size */
	  elt->private.msg.header.text.size = i;
	}
	nlseen = T;		/* note newline seen */
	break;
      default:			/* ordinary chararacter */
	i++;
	nlseen = NIL;
	break;
      }
      SETPOS (&bs,0);		/* restore old position */
      elt->rfc822_size = i;	/* note that we have size now */
				/* header is entire message if no delimiter */
      if (!elt->private.msg.header.text.size)
	elt->private.msg.header.text.size = elt->rfc822_size;
				/* text is remainder of message */
      elt->private.msg.text.text.size =
	elt->rfc822_size - elt->private.msg.header.text.size;
    }
				/* need to load cache with message data? */
    if (((flags & MLM_HEADER) && !elt->private.msg.header.text.data) ||
	((flags & MLM_TEXT) && !elt->private.msg.text.text.data)) {
				/* purge cache if too big */
      if (LOCAL->cachedtexts > max (stream->nmsgs * 4096,2097152)) {
				/* just can't keep that much */
	mail_gc (stream,GC_TEXTS);
	LOCAL->cachedtexts = 0;
      }

      if ((flags & MLM_HEADER) && !elt->private.msg.header.text.data) {
	t = elt->private.msg.header.text.data =
	  (unsigned char *) fs_get (elt->private.msg.header.text.size + 1);
	LOCAL->cachedtexts += elt->private.msg.header.text.size;
				/* read in message header */
	for (i = 0; i < elt->private.msg.header.text.size; i++)
	  switch (c = SNX (&bs)) {
	  case '\015':		/* unlikely carriage return */
	    *t++ = c;
	    if ((CHR (&bs) == '\012')) {
	      *t++ = SNX (&bs);
	      i++;
	    }
	    break;
	  case '\012':		/* line feed? */
	    *t++ = '\015';
	    i++;
	  default:
	    *t++ = c;
	    break;
	  }
	*t = '\0';		/* tie off string */
	if ((t - elt->private.msg.header.text.data) !=
	    elt->private.msg.header.text.size) fatal ("mh hdr size mismatch");
      }
      if ((flags & MLM_TEXT) && !elt->private.msg.text.text.data) {
	t = elt->private.msg.text.text.data =
	  (unsigned char *) fs_get (elt->private.msg.text.text.size + 1);
	SETPOS (&bs,elt->private.special.text.size);
	LOCAL->cachedtexts += elt->private.msg.text.text.size;
				/* read in message text */
	for (i = 0; i < elt->private.msg.text.text.size; i++)
	  switch (c = SNX (&bs)) {
	  case '\015':		/* unlikely carriage return */
	    *t++ = c;
	    if ((CHR (&bs) == '\012')) {
	      *t++ = SNX (&bs);
	      i++;
	    }
	    break;
	  case '\012':		/* line feed? */
	    *t++ = '\015';
	    i++;
	  default:
	    *t++ = c;
	    break;
	  }
	*t = '\0';		/* tie off string */
	if ((t - elt->private.msg.text.text.data) !=
	    elt->private.msg.text.text.size) fatal ("mh txt size mismatch");
      }
    }
    close (fd);			/* flush message file */
  }
}

/* MH 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 *mh_header (MAILSTREAM *stream,unsigned long msgno,unsigned long *length,
		 long flags)
{
  MESSAGECACHE *elt;
  *length = 0;			/* default to empty */
  if (flags & FT_UID) return "";/* UID call "impossible" */
  elt = mail_elt (stream,msgno);/* get elt */
  if (!elt->private.msg.header.text.data)
    mh_load_message (stream,msgno,MLM_HEADER);
  *length = elt->private.msg.header.text.size;
  return (char *) elt->private.msg.header.text.data;
}


/* MH mail fetch message text (body only)
 * Accepts: MAIL stream
 *	    message # to fetch
 *	    pointer to returned stringstruct
 *	    option flags
 * Returns: T on success, NIL on failure
 */

long mh_text (MAILSTREAM *stream,unsigned long msgno,STRING *bs,long flags)
{
  MESSAGECACHE *elt;
				/* UID call "impossible" */
  if (flags & FT_UID) return NIL;
  elt = mail_elt (stream,msgno);/* get elt */
				/* snarf message if don't have it yet */
  if (!elt->private.msg.text.text.data) {
    mh_load_message (stream,msgno,MLM_TEXT);
    if (!elt->private.msg.text.text.data) return NIL;
  }
  if (!(flags & FT_PEEK)) {	/* mark as seen */
    mail_elt (stream,msgno)->seen = T;
    mm_flags (stream,msgno);
  }
  INIT (bs,mail_string,elt->private.msg.text.text.data,
	elt->private.msg.text.text.size);
  return T;
}

/* MH mail ping mailbox
 * Accepts: MAIL stream
 * Returns: T if stream alive, else NIL
 */

long mh_ping (MAILSTREAM *stream)
{
  MAILSTREAM *sysibx = NIL;
  MESSAGECACHE *elt,*selt;
  struct stat sbuf;
  char *s,tmp[MAILTMPLEN];
  int fd;
  unsigned long i,j,r;
  unsigned long old = stream->uid_last;
  long nmsgs = stream->nmsgs;
  long recent = stream->recent;
  int silent = stream->silent;
  if (stat (LOCAL->dir,&sbuf)) {/* directory exists? */
    if (stream->inbox &&	/* no, create if INBOX */
	dummy_create_path (stream,strcat (mh_file (tmp,MHINBOX),"/"),