mmdf.c

mgcp协议源代码。支持多种编码：g711

/*
 * Program:	MMDF mail routines
 *
 * Author:	Mark Crispin
 *		Networks and Distributed Computing
 *		Computing & Communications
 *		University of Washington
 *		Administration Building, AG-44
 *		Seattle, WA  98195
 *		Internet: [e-mail]
 *
 * Date:	20 December 1989
 * Last Edited:	1 September 2000
 *
 * Copyright 2000 by the University of Washington
 *
 *  Permission to use, copy, modify, and distribute this software and its
 * documentation for any purpose and without fee is hereby granted, provided
 * that the above copyright notice appears in all copies and that both the
 * above copyright notice and this permission notice appear in supporting
 * documentation, and that the name of the University of Washington not be
 * used in advertising or publicity pertaining to distribution of the software
 * without specific, written prior permission.  This software is made
 * available "as is", and
 * THE UNIVERSITY OF WASHINGTON DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED,
 * WITH REGARD TO THIS SOFTWARE, INCLUDING WITHOUT LIMITATION ALL IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, AND IN
 * NO EVENT SHALL THE UNIVERSITY OF WASHINGTON BE LIABLE FOR ANY SPECIAL,
 * INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
 * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, TORT
 * (INCLUDING NEGLIGENCE) OR STRICT LIABILITY, ARISING OUT OF OR IN CONNECTION
 * WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 *
 */

#include <stdio.h>
#include <ctype.h>
#include <errno.h>
extern int errno;		/* just in case */
#include <signal.h>
#include "mail.h"
#include "osdep.h"
#include <time.h>
#include <sys/stat.h>
#include "mmdf.h"
#include "pseudo.h"
#include "fdstring.h"
#include "misc.h"
#include "dummy.h"

/* MMDF mail routines */


/* Driver dispatch used by MAIL */

DRIVER mmdfdriver = {
  "mmdf",			/* driver name */
  DR_LOCAL|DR_MAIL,		/* driver flags */
  (DRIVER *) NIL,		/* next driver */
  mmdf_valid,			/* mailbox is valid for us */
  mmdf_parameters,		/* manipulate parameters */
  mmdf_scan,			/* scan mailboxes */
  mmdf_list,			/* list mailboxes */
  mmdf_lsub,			/* list subscribed mailboxes */
  NIL,				/* subscribe to mailbox */
  NIL,				/* unsubscribe from mailbox */
  mmdf_create,			/* create mailbox */
  mmdf_delete,			/* delete mailbox */
  mmdf_rename,			/* rename mailbox */
  NIL,				/* status of mailbox */
  mmdf_open,			/* open mailbox */
  mmdf_close,			/* close mailbox */
  NIL,				/* fetch message "fast" attributes */
  NIL,				/* fetch message flags */
  NIL,				/* fetch overview */
  NIL,				/* fetch message envelopes */
  mmdf_header,			/* fetch message header */
  mmdf_text,			/* fetch message text */
  NIL,				/* fetch partial message text */
  NIL,				/* unique identifier */
  NIL,				/* message number */
  NIL,				/* modify flags */
  mmdf_flagmsg,			/* per-message modify flags */
  NIL,				/* search for message based on criteria */
  NIL,				/* sort messages */
  NIL,				/* thread messages */
  mmdf_ping,			/* ping mailbox to see if still alive */
  mmdf_check,			/* check for new messages */
  mmdf_expunge,			/* expunge deleted messages */
  mmdf_copy,			/* copy messages to another mailbox */
  mmdf_append,			/* append string message to mailbox */
  NIL				/* garbage collect stream */
};

				/* prototype stream */
MAILSTREAM mmdfproto = {&mmdfdriver};

char *mmdfhdr = MMDFHDRTXT;	/* MMDF header */

/* MMDF mail validate mailbox
 * Accepts: mailbox name
 * Returns: our driver if name is valid, NIL otherwise
 */

DRIVER *mmdf_valid (char *name)
{
  char tmp[MAILTMPLEN];
  return mmdf_isvalid (name,tmp) ? &mmdfdriver : NIL;
}


/* MMDF mail test for valid mailbox name
 * Accepts: mailbox name
 *	    scratch buffer
 * Returns: T if valid, NIL otherwise
 */

long mmdf_isvalid (char *name,char *tmp)
{
  int fd;
  int ret = NIL;
  char *t,file[MAILTMPLEN];
  struct stat sbuf;
  time_t tp[2];
  errno = EINVAL;		/* assume invalid argument */
				/* must be non-empty file */
  if ((t = dummy_file (file,name)) && !stat (t,&sbuf)) {
    if (!sbuf.st_size)errno = 0;/* empty file */
    else if ((fd = open (file,O_RDONLY,NIL)) >= 0) {
				/* error -1 for invalid format */
      if (!(ret = mmdf_isvalid_fd (fd,tmp))) errno = -1;
      close (fd);		/* close the file */
      tp[0] = sbuf.st_atime;	/* preserve atime and mtime */
      tp[1] = sbuf.st_mtime;
      utime (file,tp);		/* set the times */
    }
  }
				/* in case INBOX but not MMDF format */
  else if ((errno == ENOENT) && ((name[0] == 'I') || (name[0] == 'i')) &&
	   ((name[1] == 'N') || (name[1] == 'n')) &&
	   ((name[2] == 'B') || (name[2] == 'b')) &&
	   ((name[3] == 'O') || (name[3] == 'o')) &&
	   ((name[4] == 'X') || (name[4] == 'x')) && !name[5]) errno = -1;
  return ret;			/* return what we should */
}

/* MMDF mail test for valid mailbox
 * Accepts: file descriptor
 *	    scratch buffer
 * Returns: T if valid, NIL otherwise
 */

long mmdf_isvalid_fd (int fd,char *tmp)
{
  int ret = NIL;
  memset (tmp,'\0',MAILTMPLEN);
  if (read (fd,tmp,MAILTMPLEN-1) >= 0) ret = ISMMDF (tmp) ? T : NIL;
  return ret;			/* return what we should */
}


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

void *mmdf_parameters (long function,void *value)
{
  return NIL;
}

/* MMDF mail scan mailboxes
 * Accepts: mail stream
 *	    reference
 *	    pattern to search
 *	    string to scan
 */

void mmdf_scan (MAILSTREAM *stream,char *ref,char *pat,char *contents)
{
  if (stream) dummy_scan (NIL,ref,pat,contents);
}


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

void mmdf_list (MAILSTREAM *stream,char *ref,char *pat)
{
  if (stream) dummy_list (NIL,ref,pat);
}


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

void mmdf_lsub (MAILSTREAM *stream,char *ref,char *pat)
{
  if (stream) dummy_lsub (NIL,ref,pat);
}

/* MMDF mail create mailbox
 * Accepts: MAIL stream
 *	    mailbox name to create
 * Returns: T on success, NIL on failure
 */

long mmdf_create (MAILSTREAM *stream,char *mailbox)
{
  char *s,mbx[MAILTMPLEN],tmp[MAILTMPLEN];
  long ret = NIL;
  int i,fd;
  time_t ti = time (0);
  if (!(s = dummy_file (mbx,mailbox))) {
    sprintf (tmp,"Can't create %.80s: invalid name",mailbox);
    mm_log (tmp,ERROR);
  }
				/* create underlying file */
  else if (dummy_create_path (stream,s)) {
				/* done if made directory */
    if ((s = strrchr (s,'/')) && !s[1]) return T;
    if ((fd = open (mbx,O_WRONLY,
		    (int) mail_parameters (NIL,GET_MBXPROTECTION,NIL))) < 0) {
      sprintf (tmp,"Can't reopen mailbox node %.80s: %s",mbx,strerror (errno));
      mm_log (tmp,ERROR);
      unlink (mbx);		/* delete the file */
    }
				/* in case a whiner with no life */
    else if (mail_parameters (NIL,GET_USERHASNOLIFE,NIL)) ret = T;
    else {			/* initialize header */
      memset (tmp,'\0',MAILTMPLEN);
      sprintf (tmp,"%sFrom %s %sDate: ",mmdfhdr,pseudo_from,ctime (&ti));
      rfc822_date (s = tmp + strlen (tmp));
      sprintf (s += strlen (s),	/* write the pseudo-header */
	       "\nFrom: %s <%s@%s>\nSubject: %s\nX-IMAP: %010lu 0000000000",
	       pseudo_name,pseudo_from,mylocalhost (),pseudo_subject,
	       (unsigned long) ti);
      for (i = 0; i < NUSERFLAGS; ++i) if (default_user_flag (i))
	sprintf (s += strlen (s)," %s",default_user_flag (i));
      sprintf (s += strlen (s),"\nStatus: RO\n\n%s\n%s",pseudo_msg,mmdfhdr);
      if ((write (fd,tmp,strlen (tmp)) < 0) || close (fd)) {
	sprintf (tmp,"Can't initialize mailbox node %.80s: %s",mbx,
		 strerror (errno));
	mm_log (tmp,ERROR);
	unlink (mbx);		/* delete the file */
      }
      else ret = T;		/* success */
    }
    close (fd);			/* close file, set proper protections */
  }
  return ret ? set_mbx_protections (mailbox,mbx) : NIL;
}


/* MMDF mail delete mailbox
 * Accepts: MAIL stream
 *	    mailbox name to delete
 * Returns: T on success, NIL on failure
 */

long mmdf_delete (MAILSTREAM *stream,char *mailbox)
{
  return mmdf_rename (stream,mailbox,NIL);
}

/* MMDF mail rename mailbox
 * Accepts: MAIL stream
 *	    old mailbox name
 *	    new mailbox name (or NIL for delete)
 * Returns: T on success, NIL on failure
 */

long mmdf_rename (MAILSTREAM *stream,char *old,char *newname)
{
  long ret = NIL;
  char c,*s = NIL;
  char tmp[MAILTMPLEN],file[MAILTMPLEN],lock[MAILTMPLEN];
  DOTLOCK lockx;
  int fd,ld;
  long i;
  struct stat sbuf;
  mm_critical (stream);		/* get the c-client lock */
  if (newname && !((s = dummy_file (tmp,newname)) && *s))
    sprintf (tmp,"Can't rename mailbox %.80s to %.80s: invalid name",
	     old,newname);
				/* lock out other c-clients */
  else if ((ld = lockname (lock,dummy_file (file,old),LOCK_EX|LOCK_NB,&i)) < 0)
    sprintf (tmp,"Mailbox %.80s is in use by another process",old);
  else {
    if ((fd = mmdf_lock (file,O_RDWR,S_IREAD|S_IWRITE,&lockx,LOCK_EX)) < 0)
      sprintf (tmp,"Can't lock mailbox %.80s: %s",old,strerror (errno));
    else {
      if (newname) {		/* want rename? */
				/* found superior to destination name? */
	if (s = strrchr (s,'/')) {
	  c = *++s;		/* remember first character of inferior */
	  *s = '\0';		/* tie off to get just superior */
				/* name doesn't exist, create it */
	  if ((stat (tmp,&sbuf) || ((sbuf.st_mode & S_IFMT) != S_IFDIR)) &&
	      !dummy_create (stream,tmp)) {
	    mmdf_unlock (fd,NIL,&lockx);
	    mmdf_unlock (ld,NIL,NIL);
	    unlink (lock);
	    mm_nocritical (stream);
	    return ret;		/* return success or failure */
	  }
	  *s = c;		/* restore full name */
	}
	if (rename (file,tmp))
	  sprintf (tmp,"Can't rename mailbox %.80s to %.80s: %s",old,newname,
		   strerror (errno));
	else ret = T;		/* set success */
      }
      else if (unlink (file))
	sprintf (tmp,"Can't delete mailbox %.80s: %s",old,strerror (errno));
      else ret = T;		/* set success */
      mmdf_unlock (fd,NIL,&lockx);
    }
    mmdf_unlock (ld,NIL,NIL);	/* flush the lock */
    unlink (lock);
  }
  mm_nocritical (stream);	/* no longer critical */
  if (!ret) mm_log (tmp,ERROR);	/* log error */
  return ret;			/* return success or failure */
}

/* MMDF mail open
 * Accepts: Stream to open
 * Returns: Stream on success, NIL on failure
 */

MAILSTREAM *mmdf_open (MAILSTREAM *stream)
{
  long i;
  int fd;
  char tmp[MAILTMPLEN];
  DOTLOCK lock;
  long retry;
				/* return prototype for OP_PROTOTYPE call */
  if (!stream) return user_flags (&mmdfproto);
  retry = stream->silent ? 1 : KODRETRY;
  if (stream->local) fatal ("mmdf recycle stream");
  stream->local = memset (fs_get (sizeof (MMDFLOCAL)),0,sizeof (MMDFLOCAL));
				/* note if an INBOX or not */
  stream->inbox = !strcmp (ucase (strcpy (tmp,stream->mailbox)),"INBOX");
				/* canonicalize the stream mailbox name */
  dummy_file (tmp,stream->mailbox);
				/* flush old name */
  fs_give ((void **) &stream->mailbox);
				/* save canonical name */
  stream->mailbox = cpystr (tmp);
  LOCAL->fd = LOCAL->ld = -1;	/* no file or state locking yet */
  LOCAL->buf = (char *) fs_get ((LOCAL->buflen = CHUNK) + 1);
  stream->sequence++;		/* bump sequence number */

				/* make lock for read/write access */
  if (!stream->rdonly) while (retry) {
				/* try to lock file */
    if ((fd = lockname (tmp,stream->mailbox,LOCK_EX|LOCK_NB,&i)) < 0) {
      if (retry-- == KODRETRY) {/* no, first time through? */
	if (i) {		/* learned the other guy's PID? */
	  kill ((int) i,SIGUSR2);
	  sprintf (tmp,"Trying to get mailbox lock from process %ld",i);
	  mm_log (tmp,WARN);
	}
	else retry = 0;		/* give up */
      }
      if (!stream->silent) {	/* nothing if silent stream */
	if (retry) sleep (1);	/* wait a second before trying again */
	else mm_log ("Mailbox is open by another process, access is readonly",