dummydos.c

广泛使用的邮件服务器！同时

				/* notify main program */
  mm_list (stream,delimiter,name,attributes);
  return T;
}

/* Dummy create mailbox
 * Accepts: mail stream
 *	    mailbox name to create
 * Returns: T on success, NIL on failure
 */

long dummy_create (MAILSTREAM *stream,char *mailbox)
{
  char tmp[MAILTMPLEN];
  return (compare_cstring (mailbox,"INBOX") && mailboxfile (tmp,mailbox)) ?
    dummy_create_path (stream,tmp,NIL) : dummy_badname (tmp,mailbox);
}


/* Dummy create path
 * Accepts: mail stream
 *	    path name to create
 *	    directory mode
 * Returns: T on success, NIL on failure
 */

long dummy_create_path (MAILSTREAM *stream,char *path,long dirmode)
{
  struct stat sbuf;
  char c,*s,tmp[MAILTMPLEN];
  int fd;
  long ret = NIL;
  char *t = strrchr (path,'\\');
  char *pt = (path[1] == ':') ? path + 2 : path;
  int wantdir = t && !t[1];
  if (wantdir) *t = '\0';	/* flush trailing delimiter for directory */
				/* found superior to this name? */
  if ((s = strrchr (pt,'\\')) && (s != pt)) {
    strncpy (tmp,path,(size_t) (s - path));
    tmp[s - path] = '\0';	/* make directory name for stat */
    c = *++s;			/* tie off in case need to recurse */
    *s = '\0';
				/* name doesn't exist, create it */
    if ((stat (tmp,&sbuf) || ((sbuf.st_mode & S_IFMT) != S_IFDIR)) &&
	!dummy_create_path (stream,path,dirmode)) return NIL;
    *s = c;			/* restore full name */
  }
  if (wantdir) {		/* want to create directory? */
    ret = !mkdir (path);
    *t = '\\';			/* restore directory delimiter */
  }
				/* create file */
  else if ((fd = open (path,O_WRONLY|O_CREAT|O_EXCL,S_IREAD|S_IWRITE)) >= 0)
    ret = !close (fd);		/* close file */
  if (!ret) {			/* error? */
    sprintf (tmp,"Can't create mailbox node %s: %s",path,strerror (errno));
    mm_log (tmp,ERROR);
  }
  return ret;			/* return status */
}

/* Dummy delete mailbox
 * Accepts: mail stream
 *	    mailbox name to delete
 * Returns: T on success, NIL on failure
 */

long dummy_delete (MAILSTREAM *stream,char *mailbox)
{
  struct stat sbuf;
  char *s,tmp[MAILTMPLEN];
  if (!mailboxfile (tmp,mailbox)) return dummy_badname (tmp,mailbox);
				/* no trailing \ */
  if ((s = strrchr (tmp,'\\')) && !s[1]) *s = '\0';
  if (stat (tmp,&sbuf) || ((sbuf.st_mode & S_IFMT) == S_IFDIR) ?
      rmdir (tmp) : unlink (tmp)) {
    sprintf (tmp,"Can't delete mailbox %s: %s",mailbox,strerror (errno));
    mm_log (tmp,ERROR);
    return NIL;
  }
  return T;			/* return success */
}


/* Mail rename mailbox
 * Accepts: mail stream
 *	    old mailbox name
 *	    new mailbox name
 * Returns: T on success, NIL on failure
 */

long dummy_rename (MAILSTREAM *stream,char *old,char *newname)
{
  struct stat sbuf;
  char c,*s,tmp[MAILTMPLEN],file[MAILTMPLEN];
				/* make file name */
  if (!mailboxfile (file,old)) return dummy_badname (tmp,old);
				/* no trailing \ allowed */
  if (!(s = mailboxfile (tmp,newname)) || ((s = strrchr (s,'\\')) && !s[1]))
    return dummy_badname (tmp,newname);
  if (s) {			/* found superior to destination name? */
    c = *++s;			/* remember first character of inferior */
    *s = '\0';			/* tie off to get just superior */
				/* name doesn't exist, create it */
    if ((stat (file,&sbuf) || ((sbuf.st_mode & S_IFMT) != S_IFDIR)) &&
	!dummy_create (stream,file)) return NIL;
    *s = c;			/* restore full name */
  }
  if (rename (file,tmp)) {
    sprintf (tmp,"Can't rename mailbox %s to %s: %s",old,newname,
	     strerror (errno));
    mm_log (tmp,ERROR);
    return NIL;
  }
  return LONGT;			/* return success */
}

/* Dummy open
 * Accepts: stream to open
 * Returns: stream on success, NIL on failure
 */

MAILSTREAM *dummy_open (MAILSTREAM *stream)
{
  char tmp[MAILTMPLEN];
  struct stat sbuf;
  int fd = -1;
				/* OP_PROTOTYPE call or silence */
  if (!stream || stream->silent) return NIL;
  if (!mailboxfile (tmp,stream->mailbox))
    sprintf (tmp,"Can't open this name: %.80s",stream->mailbox);
  else if (compare_cstring (stream->mailbox,"INBOX") &&
      ((fd = open (tmp,O_RDONLY,NIL)) < 0))
    sprintf (tmp,"%s: %s",strerror (errno),stream->mailbox);
  else {
    if (fd >= 0) {		/* if got a file */
      fstat (fd,&sbuf);		/* sniff at its size */
      close (fd);
      if (sbuf.st_size) sprintf (tmp,"Not a mailbox: %s",stream->mailbox);
      else fd = -1;		/* a-OK */
    }
    if (fd < 0) {		/* no file, right? */
      if (!stream->silent) {	/* only if silence not requested */
				/* say there are 0 messages */
	mail_exists (stream,(long) 0);
	mail_recent (stream,(long) 0);
	stream->uid_validity = time (0);
      }
      stream->inbox = T;	/* note that it's an INBOX */
      return stream;		/* return success */
    }
  }
  mm_log (tmp,stream->silent ? WARN: ERROR);
  return NIL;			/* always fails */
}


/* Dummy close
 * Accepts: MAIL stream
 *	    options
 */

void dummy_close (MAILSTREAM *stream,long options)
{
				/* return silently */
}

/* Dummy ping mailbox
 * Accepts: MAIL stream
 * Returns: T if stream alive, else NIL
 * No-op for readonly files, since read/writer can expunge it from under us!
 */

long dummy_ping (MAILSTREAM *stream)
{
  MAILSTREAM *test;
				/* time to do another test? */
  if (time (0) >= ((time_t) (stream->gensym + 30))) {
				/* has mailbox format changed? */
    if ((test = mail_open (NIL,stream->mailbox,OP_PROTOTYPE)) &&
	(test->dtb != stream->dtb) &&
	(test = mail_open (NIL,stream->mailbox,NIL))) {
				/* preserve some resources */
      test->original_mailbox = stream->original_mailbox;
      stream->original_mailbox = NIL;
      test->sparep = stream->sparep;
      stream->sparep = NIL;
      test->sequence = stream->sequence;
      mail_close ((MAILSTREAM *) /* flush resources used by dummy stream */
		  memcpy (fs_get (sizeof (MAILSTREAM)),stream,
			  sizeof (MAILSTREAM)));
				/* swap the streams */
      memcpy (stream,test,sizeof (MAILSTREAM));
      fs_give ((void **) &test);/* flush test now that copied */
				/* make sure application knows */
      mail_exists (stream,stream->recent = stream->nmsgs);
    }
				/* still hasn't changed */
    else stream->gensym = time (0);
  }
  return T;
}


/* Dummy check mailbox
 * Accepts: MAIL stream
 * No-op for readonly files, since read/writer can expunge it from under us!
 */

void dummy_check (MAILSTREAM *stream)
{
  dummy_ping (stream);		/* invoke ping */
}


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

long dummy_expunge (MAILSTREAM *stream,char *sequence,long options)
{
  return LONGT;
}

/* Dummy copy message(s)
 * Accepts: MAIL stream
 *	    sequence
 *	    destination mailbox
 *	    options
 * Returns: T if copy successful, else NIL
 */

long dummy_copy (MAILSTREAM *stream,char *sequence,char *mailbox,long options)
{
  if ((options & CP_UID) ? mail_uid_sequence (stream,sequence) :
      mail_sequence (stream,sequence)) fatal ("Impossible dummy_copy");
  return NIL;
}


/* Dummy append message string
 * Accepts: mail stream
 *	    destination mailbox
 *	    append callback function
 *	    data for callback
 * Returns: T on success, NIL on failure
 */

long dummy_append (MAILSTREAM *stream,char *mailbox,append_t af,void *data)
{
  struct stat sbuf;
  int fd = -1;
  int e;
  char tmp[MAILTMPLEN];
  MAILSTREAM *ts = default_proto (T);
  if (compare_cstring (mailbox,"INBOX") && mailboxfile (tmp,mailbox) &&
      ((fd = open (tmp,O_RDONLY,NIL)) < 0)) {
    if ((e = errno) == ENOENT)	/* failed, was it no such file? */
      mm_notify (stream,"[TRYCREATE] Must create mailbox before append",
		 (long) NIL);
    sprintf (tmp,"%s: %s",strerror (e),mailbox);
    mm_log (tmp,ERROR);		/* pass up error */
    return NIL;			/* always fails */
  }
  if (fd >= 0) {		/* found file? */
    fstat (fd,&sbuf);		/* get its size */
    close (fd);			/* toss out the fd */
    if (sbuf.st_size) ts = NIL;	/* non-empty file? */
  }
  if (ts) return (*ts->dtb->append) (stream,mailbox,af,data);
  sprintf (tmp,"Indeterminate mailbox format: %s",mailbox);
  mm_log (tmp,ERROR);
  return NIL;
}

/* Return bad file name error message
 * Accepts: temporary buffer
 *	    file name
 * Returns: long NIL always
 */

long dummy_badname (char *tmp,char *s)
{
  sprintf (tmp,"Invalid mailbox name: %s",s);
  mm_log (tmp,ERROR);
  return (long) NIL;
}


/* Dummy canonicalize name
 * Accepts: buffer to write name
 *	    reference
 *	    pattern
 * Returns: T if success, NIL if failure
 */

long dummy_canonicalize (char *tmp,char *ref,char *pat)
{
  unsigned long i;
  char *s,dev[4];
				/* initially no device */
  dev[0] = dev[1] = dev[2] = dev[3] = '\0';
  if (ref) switch (*ref) {	/* preliminary reference check */
  case '{':			/* remote names not allowed */
    return NIL;			/* disallowed */
  case '\0':			/* empty reference string */
    break;
  default:			/* all other names */
    if (ref[1] == ':') {	/* start with device name? */
      dev[0] = *ref++; dev[1] = *ref++;
    }
    break;
  }
  if (pat[1] == ':') {		/* device name in pattern? */
    dev[0] = *pat++; dev[1] = *pat++;
    ref = NIL;			/* ignore reference */
  }
  switch (*pat) {
  case '#':			/* namespace names */
    if (mailboxfile (tmp,pat)) strcpy (tmp,pat);
    else return NIL;		/* unknown namespace */
    break;
  case '{':			/* remote names not allowed */
    return NIL;
  case '\\':			/* rooted name */
    ref = NIL;			/* ignore reference */
    break;
  }
				/* make sure device names are rooted */
  if (dev[0] && (*(ref ? ref : pat) != '\\')) dev[2] = '\\';
				/* build name */
  sprintf (tmp,"%s%s%s",dev,ref ? ref : "",pat);
  ucase (tmp);			/* force upper case */
				/* count wildcards */
  for (i = 0, s = tmp; *s; *s++) if ((*s == '*') || (*s == '%')) ++i;
  if (i > MAXWILDCARDS) {	/* ridiculous wildcarding? */
    MM_LOG ("Excessive wildcards in LIST/LSUB",ERROR);
    return NIL;
  }
  return T;
}