dummy.c

广泛使用的邮件服务器！同时

/* ========================================================================
 * Copyright 1988-2007 University of Washington
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * 
 * ========================================================================
 */

/*
 * Program:	Dummy routines
 *
 * Author:	Mark Crispin
 *		Networks and Distributed Computing
 *		Computing & Communications
 *		University of Washington
 *		Administration Building, AG-44
 *		Seattle, WA  98195
 *		Internet: [e-mail]
 *
 * Date:	9 May 1991
 * Last Edited:	1 June 2007
 */


#include <stdio.h>
#include <ctype.h>
#include <errno.h>
extern int errno;		/* just in case */
#include "mail.h"
#include "osdep.h"
#include <pwd.h>
#include <sys/stat.h>
#include "dummy.h"
#include "misc.h"

/* Function prototypes */

DRIVER *dummy_valid (char *name);
void *dummy_parameters (long function,void *value);
void dummy_list_work (MAILSTREAM *stream,char *dir,char *pat,char *contents,
		      long level);
long dummy_listed (MAILSTREAM *stream,char delimiter,char *name,
		   long attributes,char *contents);
long dummy_subscribe (MAILSTREAM *stream,char *mailbox);
MAILSTREAM *dummy_open (MAILSTREAM *stream);
void dummy_close (MAILSTREAM *stream,long options);
long dummy_ping (MAILSTREAM *stream);
void dummy_check (MAILSTREAM *stream);
long dummy_expunge (MAILSTREAM *stream,char *sequence,long options);
long dummy_copy (MAILSTREAM *stream,char *sequence,char *mailbox,long options);
long dummy_append (MAILSTREAM *stream,char *mailbox,append_t af,void *data);

/* Dummy routines */


/* Driver dispatch used by MAIL */

DRIVER dummydriver = {
  "dummy",			/* driver name */
  DR_LOCAL|DR_MAIL,		/* driver flags */
  (DRIVER *) NIL,		/* next driver */
  dummy_valid,			/* mailbox is valid for us */
  dummy_parameters,		/* manipulate parameters */
  dummy_scan,			/* scan mailboxes */
  dummy_list,			/* list mailboxes */
  dummy_lsub,			/* list subscribed mailboxes */
  dummy_subscribe,		/* subscribe to mailbox */
  NIL,				/* unsubscribe from mailbox */
  dummy_create,			/* create mailbox */
  dummy_delete,			/* delete mailbox */
  dummy_rename,			/* rename mailbox */
  mail_status_default,		/* status of mailbox */
  dummy_open,			/* open mailbox */
  dummy_close,			/* close mailbox */
  NIL,				/* fetch message "fast" attributes */
  NIL,				/* fetch message flags */
  NIL,				/* fetch overview */
  NIL,				/* fetch message structure */
  NIL,				/* fetch header */
  NIL,				/* fetch text */
  NIL,				/* fetch message data */
  NIL,				/* unique identifier */
  NIL,				/* message number from UID */
  NIL,				/* modify flags */
  NIL,				/* per-message modify flags */
  NIL,				/* search for message based on criteria */
  NIL,				/* sort messages */
  NIL,				/* thread messages */
  dummy_ping,			/* ping mailbox to see if still alive */
  dummy_check,			/* check for new messages */
  dummy_expunge,		/* expunge deleted messages */
  dummy_copy,			/* copy messages to another mailbox */
  dummy_append,			/* append string message to mailbox */
  NIL				/* garbage collect stream */
};

				/* prototype stream */
MAILSTREAM dummyproto = {&dummydriver};

/* Dummy validate mailbox
 * Accepts: mailbox name
 * Returns: our driver if name is valid, NIL otherwise
 */

DRIVER *dummy_valid (char *name)
{
  char *s,tmp[MAILTMPLEN];
  struct stat sbuf;
				/* must be valid local mailbox */
  if (name && *name && (*name != '{') && (s = mailboxfile (tmp,name))) {
				/* indeterminate clearbox INBOX */
    if (!*s) return &dummydriver;
    else if (!stat (s,&sbuf)) switch (sbuf.st_mode & S_IFMT) {
    case S_IFREG:
    case S_IFDIR:
      return &dummydriver;
    }
				/* blackbox INBOX does not exist yet */
    else if (!compare_cstring (name,"INBOX")) return &dummydriver;
  }
  return NIL;
}


/* Dummy manipulate driver parameters
 * Accepts: function code
 *	    function-dependent value
 * Returns: function-dependent return value
 */

void *dummy_parameters (long function,void *value)
{
  void *ret = NIL;
  switch ((int) function) {
  case GET_INBOXPATH:
    if (value) ret = dummy_file ((char *) value,"INBOX");
    break;
  }
  return ret;
}

/* Dummy scan mailboxes
 * Accepts: mail stream
 *	    reference
 *	    pattern to search
 *	    string to scan
 */

void dummy_scan (MAILSTREAM *stream,char *ref,char *pat,char *contents)
{
  DRIVER *drivers;
  char *s,test[MAILTMPLEN],file[MAILTMPLEN];
  long i;
  if (!pat || !*pat) {		/* empty pattern? */
    if (dummy_canonicalize (test,ref,"*")) {
				/* tie off name at root */
      if (s = strchr (test,'/')) *++s = '\0';
      else test[0] = '\0';
      dummy_listed (stream,'/',test,LATT_NOSELECT,NIL);
    }
  }
				/* get canonical form of name */
  else if (dummy_canonicalize (test,ref,pat)) {
				/* found any wildcards? */
    if (s = strpbrk (test,"%*")) {
				/* yes, copy name up to that point */
      strncpy (file,test,i = s - test);
      file[i] = '\0';		/* tie off */
    }
    else strcpy (file,test);	/* use just that name then */
    if (s = strrchr (file,'/')){/* find directory name */
      *++s = '\0';		/* found, tie off at that point */
      s = file;
    }
				/* silly case */
    else if ((file[0] == '~') || (file[0] == '#')) s = file;
				/* do the work */
    dummy_list_work (stream,s,test,contents,0);
				/* always an INBOX */
    if (pmatch ("INBOX",ucase (test))) {
				/* done if have a dirfmt INBOX */
      for (drivers = (DRIVER *) mail_parameters (NIL,GET_DRIVERS,NIL);
	   drivers && !(!(drivers->flags & DR_DISABLE) &&
			(drivers->flags & DR_DIRFMT) &&
			(*drivers->valid) ("INBOX")); drivers = drivers->next);
				/* list INBOX appropriately */
      dummy_listed (stream,drivers ? '/' : NIL,"INBOX",
		    drivers ? NIL : LATT_NOINFERIORS,contents);
    }
  }
}


/* Dummy list mailboxes
 * Accepts: mail stream
 *	    reference
 *	    pattern to search
 */

void dummy_list (MAILSTREAM *stream,char *ref,char *pat)
{
  dummy_scan (stream,ref,pat,NIL);
}

/* Dummy list subscribed mailboxes
 * Accepts: mail stream
 *	    reference
 *	    pattern to search
 */

void dummy_lsub (MAILSTREAM *stream,char *ref,char *pat)
{
  void *sdb = NIL;
  char *s,*t,test[MAILTMPLEN],tmp[MAILTMPLEN];
  int showuppers = pat[strlen (pat) - 1] == '%';
				/* get canonical form of name */
  if (dummy_canonicalize (test,ref,pat) && (s = sm_read (&sdb))) do
    if (*s != '{') {
      if (!compare_cstring (s,"INBOX") &&
	  pmatch ("INBOX",ucase (strcpy (tmp,test))))
	mm_lsub (stream,NIL,s,LATT_NOINFERIORS);
      else if (pmatch_full (s,test,'/')) mm_lsub (stream,'/',s,NIL);
      else while (showuppers && (t = strrchr (s,'/'))) {
	*t = '\0';		/* tie off the name */
	if (pmatch_full (s,test,'/')) mm_lsub (stream,'/',s,LATT_NOSELECT);
      }
    }
  while (s = sm_read (&sdb));	/* until no more subscriptions */
}


/* Dummy subscribe to mailbox
 * Accepts: mail stream
 *	    mailbox to add to subscription list
 * Returns: T on success, NIL on failure
 */

long dummy_subscribe (MAILSTREAM *stream,char *mailbox)
{
  char *s,tmp[MAILTMPLEN];
  struct stat sbuf;
				/* must be valid local mailbox */
  if ((s = mailboxfile (tmp,mailbox)) && *s && !stat (s,&sbuf))
    switch (sbuf.st_mode & S_IFMT) {
    case S_IFDIR:		/* allow but snarl */
      sprintf (tmp,"CLIENT BUG DETECTED: subscribe of non-mailbox directory %.80s",
	       mailbox);
      MM_NOTIFY (stream,tmp,WARN);
    case S_IFREG:
      return sm_subscribe (mailbox);
    }
  sprintf (tmp,"Can't subscribe %.80s: not a mailbox",mailbox);
  MM_LOG (tmp,ERROR);
  return NIL;
}

/* Dummy list mailboxes worker routine
 * Accepts: mail stream
 *	    directory name to search
 *	    search pattern
 *	    string to scan
 *	    search level
 */

void dummy_list_work (MAILSTREAM *stream,char *dir,char *pat,char *contents,
		      long level)
{
  DRIVER *drivers;
  dirfmttest_t dt;
  DIR *dp;
  struct direct *d;
  struct stat sbuf;
  char tmp[MAILTMPLEN],path[MAILTMPLEN];
  size_t len = 0;
				/* punt if bogus name */
  if (!mailboxdir (tmp,dir,NIL)) return;
  if (dp = opendir (tmp)) {	/* do nothing if can't open directory */
				/* see if a non-namespace directory format */
    for (drivers = (DRIVER *) mail_parameters (NIL,GET_DRIVERS,NIL), dt = NIL;
	 dir && !dt && drivers; drivers = drivers->next)
      if (!(drivers->flags & DR_DISABLE) && (drivers->flags & DR_DIRFMT) &&
	  (*drivers->valid) (dir))
	dt = mail_parameters ((*drivers->open) (NIL),GET_DIRFMTTEST,NIL);
				/* list it if at top-level */
    if (!level && dir && pmatch_full (dir,pat,'/') && !pmatch (dir,"INBOX"))
      dummy_listed (stream,'/',dir,dt ? NIL : LATT_NOSELECT,contents);

				/* scan directory, ignore . and .. */
    if (!dir || dir[(len = strlen (dir)) - 1] == '/') while (d = readdir (dp))
      if ((!(dt && (*dt) (d->d_name))) &&
	  ((d->d_name[0] != '.') ||
	   (((long) mail_parameters (NIL,GET_HIDEDOTFILES,NIL)) ? NIL :
	    (d->d_name[1] && (((d->d_name[1] != '.') || d->d_name[2]))))) &&
	  ((len + strlen (d->d_name)) <= NETMAXMBX)) {
				/* see if name is useful */
	if (dir) sprintf (tmp,"%s%s",dir,d->d_name);
	else strcpy (tmp,d->d_name);
				/* make sure useful and can get info */
	if ((pmatch_full (strcpy (path,tmp),pat,'/') ||
	     pmatch_full (strcat (path,"/"),pat,'/') ||
	     dmatch (path,pat,'/')) &&
	    mailboxdir (path,dir,"x") && (len = strlen (path)) &&
	    strcpy (path+len-1,d->d_name) && !stat (path,&sbuf)) {
				/* only interested in file type */
	  switch (sbuf.st_mode & S_IFMT) {
	  case S_IFDIR:		/* directory? */
				/* form with trailing / */
	    sprintf (path,"%s/",tmp);
				/* skip listing if INBOX */
	    if (!pmatch (tmp,"INBOX")) {
	      if (pmatch_full (tmp,pat,'/')) {
		if (!dummy_listed (stream,'/',tmp,LATT_NOSELECT,contents))
		  break;
	      }
				/* try again with trailing / */
	      else if (pmatch_full (path,pat,'/') &&
		       !dummy_listed (stream,'/',path,LATT_NOSELECT,contents))
		break;
	    }
	    if (dmatch (path,pat,'/') &&
		(level < (long) mail_parameters (NIL,GET_LISTMAXLEVEL,NIL)))
	      dummy_list_work (stream,path,pat,contents,level+1);
	    break;
	  case S_IFREG:		/* ordinary name */
	    /* Must use ctime for systems that don't update mtime properly */
	    if (pmatch_full (tmp,pat,'/') && compare_cstring (tmp,"INBOX"))
	      dummy_listed (stream,'/',tmp,LATT_NOINFERIORS +
			    ((sbuf.st_size && (sbuf.st_atime < sbuf.st_ctime))?
			     LATT_MARKED : LATT_UNMARKED),contents);
	    break;
	  }
	}
      }
    closedir (dp);		/* all done, flush directory */
  }
}

/* Scan file for contents
 * Accepts: driver to use
 *	    file name
 *	    desired contents
 *	    length of contents
 *	    size of file
 * Returns: NIL if contents not found, T if found
 */

long scan_contents (DRIVER *dtb,char *name,char *contents,
		    unsigned long csiz,unsigned long fsiz)
{
  scancontents_t sc = dtb ?
    (scancontents_t) (*dtb->parameters) (GET_SCANCONTENTS,NIL) : NIL;
  return (*(sc ? sc : dummy_scan_contents)) (name,contents,csiz,fsiz);
}


/* Scan file for contents
 * Accepts: file name
 *	    desired contents
 *	    length of contents
 *	    size of file
 * Returns: NIL if contents not found, T if found
 */

#define BUFSIZE 4*MAILTMPLEN

long dummy_scan_contents (char *name,char *contents,unsigned long csiz,
			  unsigned long fsiz)
{
  int fd;
  unsigned long ssiz,bsiz;
  char *buf;
				/* forget it if can't select or open */
  if ((fd = open (name,O_RDONLY,NIL)) >= 0) {
				/* get buffer including slop */    
    buf = (char *) fs_get (BUFSIZE + (ssiz = 4 * ((csiz / 4) + 1)) + 1);
    memset (buf,'\0',ssiz);	/* no slop area the first time */
    while (fsiz) {		/* until end of file */
      read (fd,buf+ssiz,bsiz = min (fsiz,BUFSIZE));
      if (search ((unsigned char *) buf,bsiz+ssiz,
		  (unsigned char *) contents,csiz)) break;
      memcpy (buf,buf+BUFSIZE,ssiz);
      fsiz -= bsiz;		/* note that we read that much */
    }
    fs_give ((void **) &buf);	/* flush buffer */
    close (fd);			/* finished with file */
    if (fsiz) return T;		/* found */
  }
  return NIL;			/* not found */
}

/* Mailbox found
 * Accepts: MAIL stream
 *	    hierarchy delimiter
 *	    mailbox name
 *	    attributes
 *	    contents to search before calling mm_list()
 * Returns: NIL if should abort hierarchy search, else T (currently always)
 */

long dummy_listed (MAILSTREAM *stream,char delimiter,char *name,