unixnt.c

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    break;
  }
  if (fputs ("\r\n",sf) == EOF) return NIL;
  while (uf)			/* write user flags */    
    if ((s = stream->user_flags[find_rightmost_bit (&uf)]) &&
	(fprintf (sf," %s",s) < 0)) return NIL;
  if (fputs ("\r\n",sf) == EOF) return NIL;
  while (SIZE (msg)) {		/* copy text to scratch file */
    for (s = (unsigned char *) msg->curpos, t = s + msg->cursize; s < t; ++s)
      if (!*s) *s = 0x80;	/* disallow NUL */
				/* write buffered text */
    if (fwrite (msg->curpos,1,msg->cursize,sf) == msg->cursize)
      SETPOS (msg,GETPOS (msg) + msg->cursize);
    else return NIL;		/* failed */
  }
				/* write trailing CRLF and return */
  return (fputs ("\r\n",sf) == EOF) ? NIL : T;
}

/* Append messages from scratch file to mailbox
 * Accepts: MAIL stream
 *	    source file
 *	    destination file
 *	    uidset to update if non-NIL
 * Returns: T if success, NIL if failure
 */

int unix_append_msgs (MAILSTREAM *stream,FILE *sf,FILE *df,SEARCHSET *set)
{
  int ti,zn,c;
  long f;
  unsigned long i,j;
  char *x,tmp[MAILTMPLEN];
  int hdrp = T;
				/* get message metadata line */
  while (fgets (tmp,MAILTMPLEN,sf)) {
    if (!(isdigit (tmp[0]) && strchr (tmp,'\n'))) return NIL;
    f = strtol (tmp,&x,10);	/* get flags */
    if (!((*x++ == ' ') && isdigit (*x))) return NIL;
    i = strtoul (x,&x,10);	/* get message size */
    if ((*x++ != ' ') ||	/* build initial header */
	(fprintf (df,"From %s@%s %sStatus: ",myusername(),mylocalhost(),x)<0)||
	(f&fSEEN && (putc ('R',df) == EOF)) ||
	(fputs ("\r\nX-Status: ",df) == EOF) ||
	(f&fDELETED && (putc ('D',df) == EOF)) ||
	(f&fFLAGGED && (putc ('F',df) == EOF)) ||
	(f&fANSWERED && (putc ('A',df) == EOF)) ||
	(f&fDRAFT && (putc ('T',df) == EOF)) ||
	(fputs ("\r\nX-Keywords:",df) == EOF)) return NIL;
				/* copy keywords */
    while ((c = getc (sf)) != '\n') switch (c) {
    case EOF:
      return NIL;
    default:
      if (putc (c,df) == EOF) return NIL;
    }
    if ((putc ('\n',df) == EOF) ||
	(set && (fprintf (df,"X-UID: %lu\r\n",++(stream->uid_last)) < 0)))
      return NIL;

    for (c = '\n'; i && fgets (tmp,MAILTMPLEN,sf); c = tmp[j-1]) {
				/* get read line length */
      if (i < (j = strlen (tmp))) fatal ("unix_append_msgs overrun");
      i -= j;			/* number of bytes left */
      if (!j) continue;		/* do nothing if line emptied */
				/* complete line? */
      if ((c == '\n')) switch (tmp[0]) {
      case 'F':			/* possible "From " (case counts here) */
	if ((j > 4) && (tmp[0] == 'F') && (tmp[1] == 'r') && (tmp[2] == 'o') &&
	    (tmp[3] == 'm') && (tmp[4] == ' ')) {
	  if (!unix_fromwidget) {
	    VALID (tmp,x,ti,zn);/* conditional, only write widget if */
	    if (!ti) break;	/*  it looks like a valid header */
	  }			/* write the widget */
	  if (putc ('>',df) == EOF) return NIL;
	}
	break;
      case 'S': case 's':	/* possible "Status:" */
	if (hdrp && (j > 6) && ((tmp[1] == 't') || (tmp[1] == 'T')) &&
	    ((tmp[2] == 'a') || (tmp[2] == 'A')) &&
	    ((tmp[3] == 't') || (tmp[3] == 'T')) &&
	    ((tmp[4] == 'u') || (tmp[4] == 'U')) &&
	    ((tmp[5] == 's') || (tmp[5] == 'S')) && (tmp[6] == ':') &&
	    (fputs ("X-Original-",df) == EOF)) return NIL;
	break;
      case 'X': case 'x':	/* possible X-??? header */
	if (hdrp && (tmp[1] == '-') &&
				/* possible X-UID: */
	    (((j > 5) && ((tmp[2] == 'U') || (tmp[2] == 'u')) &&
	      ((tmp[3] == 'I') || (tmp[3] == 'i')) &&
	      ((tmp[4] == 'D') || (tmp[4] == 'd')) && (tmp[5] == ':')) ||
				/* possible X-IMAP: */
	     ((j > 6) && ((tmp[2] == 'I') || (tmp[2] == 'i')) &&
	      ((tmp[3] == 'M') || (tmp[3] == 'm')) &&
	      ((tmp[4] == 'A') || (tmp[4] == 'a')) &&
	      ((tmp[5] == 'P') || (tmp[5] == 'p')) &&
	      ((tmp[6] == ':') ||
				/* or X-IMAPbase: */
	       ((j > 10) && ((tmp[6] == 'b') || (tmp[6] == 'B')) &&
		((tmp[7] == 'a') || (tmp[7] == 'A')) &&
		((tmp[8] == 's') || (tmp[8] == 'S')) &&
		((tmp[9] == 'e') || (tmp[9] == 'E')) && (tmp[10] == ':')))) ||
				/* possible X-Status: */
	     ((j > 8) && ((tmp[2] == 'S') || (tmp[2] == 's')) &&
	      ((tmp[3] == 't') || (tmp[3] == 'T')) &&
	      ((tmp[4] == 'a') || (tmp[4] == 'A')) &&
	      ((tmp[5] == 't') || (tmp[5] == 'T')) &&
	      ((tmp[6] == 'u') || (tmp[6] == 'U')) &&
	      ((tmp[7] == 's') || (tmp[7] == 'S')) && (tmp[8] == ':')) ||
				/* possible X-Keywords: */
	     ((j > 10) && ((tmp[2] == 'K') || (tmp[2] == 'k')) &&
	      ((tmp[3] == 'e') || (tmp[3] == 'E')) &&
	      ((tmp[4] == 'y') || (tmp[4] == 'Y')) &&
	      ((tmp[5] == 'w') || (tmp[5] == 'W')) &&
	      ((tmp[6] == 'o') || (tmp[6] == 'O')) &&
	      ((tmp[7] == 'r') || (tmp[7] == 'R')) &&
	      ((tmp[8] == 'd') || (tmp[8] == 'D')) &&
	      ((tmp[9] == 's') || (tmp[9] == 'S')) && (tmp[10] == ':'))) &&
	    (fputs ("X-Original-",df) == EOF)) return NIL;
	break;
      case '\n':		/* blank line */
	hdrp = NIL;
	break;
      default:			/* nothing to do */
	break;
      }
				/* just write the line */
      if (fwrite (tmp,1,j,df) != j) return NIL;
    }
    if (i) return NIL;		/* didn't read entire message */
				/* update set */
    if (stream) mail_append_set (set,stream->uid_last);
  }
  return T;
}

/* Internal routines */


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

void unix_abort (MAILSTREAM *stream)
{
  if (LOCAL) {			/* only if a file is open */
    if (LOCAL->fd >= 0) close (LOCAL->fd);
    if (LOCAL->ld >= 0) {	/* have a mailbox lock? */
      flock (LOCAL->ld,LOCK_UN);/* yes, release the lock */
      close (LOCAL->ld);	/* close the lock file */
      unlink (LOCAL->lname);	/* and delete it */
    }
    if (LOCAL->lname) fs_give ((void **) &LOCAL->lname);
				/* free local text buffers */
    if (LOCAL->buf) fs_give ((void **) &LOCAL->buf);
    if (LOCAL->text.data) fs_give ((void **) &LOCAL->text.data);
    if (LOCAL->linebuf) fs_give ((void **) &LOCAL->linebuf);
    if (LOCAL->line) fs_give ((void **) &LOCAL->line);
				/* nuke the local data */
    fs_give ((void **) &stream->local);
    stream->dtb = NIL;		/* log out the DTB */
  }
}

/* UNIX open and lock mailbox
 * Accepts: file name to open/lock
 *	    file open mode
 *	    destination buffer for lock file name
 *	    type of locking operation (LOCK_SH or LOCK_EX)
 */

int unix_lock (char *file,int flags,int mode,char *lock,int op)
{
  int fd,ld,j;
  int i = LOCKTIMEOUT * 60 - 1;
  char tmp[MAILTMPLEN];
  time_t t;
  struct stat sb;
  sprintf (lock,"%s.lock",file);/* build lock filename */
  do {				/* until OK or out of tries */
    t = time (0);		/* get the time now */
				/* try to get the lock */
    if ((ld = open(lock,O_BINARY|O_WRONLY|O_CREAT|O_EXCL,S_IREAD|S_IWRITE))>=0)
      close (ld);		/* got it, close the lock file! */
    else if (errno != EEXIST) {	/* miscellaneous error */
      sprintf (tmp,"Error creating %.80s: %s",lock,strerror (errno));
      if (!(i%15)) mm_log (tmp,WARN);
    }
				/* lock exists, still active? */
    else if (!stat (lock,&sb) && (t > sb.st_ctime + LOCKTIMEOUT * 60) &&
	     ((ld = open(lock,O_BINARY|O_WRONLY|O_CREAT,S_IREAD|S_IWRITE))>=0))
      close (ld);		/* got timed-out lock file */
    else {			/* active lock, try again */
      if (!(i%15)) {
	sprintf (tmp,"Mailbox %.80s is locked, will override in %d seconds...",
		 file,i);
	mm_log (tmp,WARN);
      }
      sleep (1);		/* wait a second before next retry */
    }
  } while (*lock && ld < 0 && i--);
				/* open file */
  if ((fd = open (file,flags,mode)) >= 0) flock (fd,op);
  else {			/* open failed */
    j = errno;			/* preserve error code */
    if (*lock) unlink (lock);	/* flush the lock file if any */
    errno = j;			/* restore error code */
  }
  return fd;
}

/* UNIX unlock and close mailbox
 * Accepts: file descriptor
 *	    (optional) mailbox stream to check atime/mtime
 *	    (optional) lock file name
 */

void unix_unlock (int fd,MAILSTREAM *stream,char *lock)
{
  if (stream) {			/* need to muck with times? */
    struct stat sbuf;
    struct utimbuf times;
    time_t now = time (0);
    fstat (fd,&sbuf);		/* get file times */
    if (LOCAL->ld >= 0) {	/* yes, readwrite session? */
      times.actime = now;	/* set atime to now */
				/* set mtime to (now - 1) if necessary */
      times.modtime = (now > sbuf.st_mtime) ? sbuf.st_mtime : now - 1;
    }
    else if (stream->recent) {	/* readonly with recent messages */
      if ((sbuf.st_atime >= sbuf.st_mtime) ||
	  (sbuf.st_atime >= sbuf.st_ctime))
				/* keep past mtime, whack back atime */
	times.actime = (times.modtime = (sbuf.st_mtime < now) ?
			sbuf.st_mtime : now) - 1;
      else now = 0;		/* no time change needed */
    }
				/* readonly with no recent messages */
    else if ((sbuf.st_atime < sbuf.st_mtime) ||
	     (sbuf.st_atime < sbuf.st_ctime)) {
      times.actime = now;	/* set atime to now */
				/* set mtime to (now - 1) if necessary */
      times.modtime = (now > sbuf.st_mtime) ? sbuf.st_mtime : now - 1;
    }
    else now = 0;		/* no time change needed */
				/* set the times, note change */
    if (now && !utime (stream->mailbox,&times))
      LOCAL->filetime = times.modtime;
  }
  flock (fd,LOCK_UN);		/* release flock'ers */
  if (!stream) close (fd);	/* close the file if no stream */
				/* flush the lock file if any */
  if (lock && *lock) unlink (lock);
}

/* UNIX mail parse and lock mailbox
 * Accepts: MAIL stream
 *	    space to write lock file name
 *	    type of locking operation
 * Returns: T if parse OK, critical & mailbox is locked shared; NIL if failure
 */

int unix_parse (MAILSTREAM *stream,char *lock,int op)
{
  int zn;
  unsigned long i,j,k,m;
  unsigned char c,*s,*t,*u,tmp[MAILTMPLEN],date[30];
  int ti = 0,retain = T;
  unsigned long nmsgs = stream->nmsgs;
  unsigned long prevuid = nmsgs ? mail_elt (stream,nmsgs)->private.uid : 0;
  unsigned long recent = stream->recent;
  unsigned long oldnmsgs = stream->nmsgs;
  short silent = stream->silent;
  short pseudoseen = NIL;
  struct stat sbuf;
  STRING bs;
  FDDATA d;
  MESSAGECACHE *elt;
  mail_lock (stream);		/* guard against recursion or pingers */
				/* toss out previous descriptor */
  if (LOCAL->fd >= 0) close (LOCAL->fd);
  mm_critical (stream);		/* open and lock mailbox (shared OK) */
  if ((LOCAL->fd = unix_lock (stream->mailbox,
			      O_BINARY + ((LOCAL->ld >= 0) ? O_RDWR:O_RDONLY),
			      NIL,lock,op)) < 0) {
    sprintf (tmp,"Mailbox open failed, aborted: %s",strerror (errno));
    mm_log (tmp,ERROR);
    unix_abort (stream);
    mail_unlock (stream);
    mm_nocritical (stream);	/* done with critical */
    return NIL;
  }
  fstat (LOCAL->fd,&sbuf);	/* get status */
				/* validate change in size */
  if (sbuf.st_size < LOCAL->filesize) {
    sprintf (tmp,"Mailbox shrank from %lu to %lu bytes, aborted",
	     (unsigned long) LOCAL->filesize,(unsigned long) sbuf.st_size);
    mm_log (tmp,ERROR);		/* this is pretty bad */
    unix_unlock (LOCAL->fd,stream,lock);
    unix_abort (stream);
    mail_unlock (stream);
    mm_nocritical (stream);	/* done with critical */
    return NIL;
  }

				/* new data? */
  else if (i = sbuf.st_size - LOCAL->filesize) {
    d.fd = LOCAL->fd;		/* yes, set up file descriptor */
    d.pos = LOCAL->filesize;	/* get to that position in the file */
    d.chunk = LOCAL->buf;	/* initial buffer chunk */
    d.chunksize = CHUNKSIZE;	/* file chunk size */
    INIT (&bs,fd_string,&d,i);	/* initialize stringstruct */
				/* skip leading whitespace for broken MTAs */
    while (((c = CHR (&bs)) == '\n') || (c == '\r') ||
	   (c == ' ') || (c == '\t')) SNX (&bs);
    if (SIZE (&bs)) {		/* read new data */
				/* remember internal header position */
      j = LOCAL->filesize + GETPOS (&bs);
      s = unix_mbxline (stream,&bs,&i);
      t = NIL,zn = 0;
      if (i) VALID (s,t,ti,zn);	/* see if valid From line */
      if (!ti) {		/* someone pulled the rug from under us */
	sprintf (tmp,"Unexpected changes to mailbox (try restarting): %.20s",
		 (char *) s);
	mm_log (tmp,ERROR);
	unix_unlock (LOCAL->fd,stream,lock);
	unix_abort (stream);
	mail_unlock (stream);
	mm_nocritical (stream);	/* done with critical */
	return NIL;
      }
      stream->silent = T;	/* quell main program new message events */
      do {			/* found a message */
				/* instantiate first new message */
	mail_exists (stream,++nmsgs);
	(elt = mail_elt (stream,nmsgs))->valid = T;
	recent++;		/* assume recent by default */
	elt->recent = T;
				/* note position/size of internal header */
	elt->private.special.offset = j;
	elt->private.msg.header.offset = elt->private.special.text.size = i;

				/* generate plausible IMAPish date string */
	date[2] = date[6] = date[20] = '-'; date[11] = ' ';
	date[14] = date[17] = ':';
				/* dd */
	date[0] = t[ti - 2]; date[1] = t[ti - 1];
				/* mmm */
	date[3] = t[ti - 6]; date[4] = t[ti - 5]; date[5] = t[ti - 4];
				/* hh */
	date[12] = t[ti + 1]; date[13] = t[ti + 2];
				/* mm */
	date[15] = t[ti + 4]; date[16] = t[ti + 5];
	if (t[ti += 6] == ':') {/* ss */
	  date[18] = t[++ti]; date[19] = t[++ti];
	  ti++;			/* move to space */
	}
	else date[18] = date[19] = '0';
				/* yy -- advance over timezone if necessary */
	if (zn == ti) ti += (((t[zn+1] == '+') || (t[zn+1] == '-')) ? 6 : 4);
	date[7] = t[ti + 1]; date[8] = t[ti + 2];
	date[9] = t[ti + 3]; date[10] = t[ti + 4];
				/* zzz */
	t = zn ? (t + zn + 1) : (unsigned char *) "LCL";
	date[21] = *t++; date[22] = *t++; date[23] = *t++;
	if ((date[21] != '+') && (date[21] != '-')) date[24] = '\0';
	else {			/* numeric time zone */
	  date[24] = *t++; date[25] = *t++;
	  date[26] = '\0'; date[20] = ' ';
	}
				/* set internal date */
	if (!mail_parse_date (elt,date)) {
	  sprintf (tmp,"Unable to parse internal date: %s",(char *) date);
	  mm_log (tmp,WARN);
	}