/* bc_generate.c -- sieve bytecode- almost flattened bytecode
 * Rob Siemborski
 *
 * Copyright (c) 1994-2008 Carnegie Mellon University.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The name "Carnegie Mellon University" must not be used to
 *    endorse or promote products derived from this software without
 *    prior written permission. For permission or any legal
 *    details, please contact
 *      Carnegie Mellon University
 *      Center for Technology Transfer and Enterprise Creation
 *      4615 Forbes Avenue
 *      Suite 302
 *      Pittsburgh, PA  15213
 *      (412) 268-7393, fax: (412) 268-7395
 *      innovation@andrew.cmu.edu
 *
 * 4. Redistributions of any form whatsoever must retain the following
 *    acknowledgment:
 *    "This product includes software developed by Computing Services
 *     at Carnegie Mellon University (http://www.cmu.edu/computing/)."
 *
 * CARNEGIE MELLON UNIVERSITY DISCLAIMS ALL WARRANTIES WITH REGARD TO
 * THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
 * AND FITNESS, IN NO EVENT SHALL CARNEGIE MELLON UNIVERSITY 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, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
 * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 *
 * $Id: bc_generate.c,v 1.6 2010/01/06 17:01:58 murch Exp $
 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include "xmalloc.h"
#include "sieve_interface.h"

#include "script.h"
#include "tree.h"
#include "sieve.h"

#include "bytecode.h"

#include <assert.h>
#include <string.h>



struct bytecode_info 
{
    bytecode_t *data;/* pointer to almost-flat bytecode */
    size_t scriptend; /* used by emit code to know final length of bytecode */
    size_t reallen; /* allocated length of 'data' */
};

static int bc_test_generate(int codep, bytecode_info_t *retval, test_t *t);

/* returns false if the request can't be satisfied, true if it can. */

static int atleast(bytecode_info_t *arr, size_t len) 
{
    if(arr->reallen < len) {
	/* too small; double if that's big enough, otherwise increase to the
	   requested size. */
	arr->reallen = (len > arr->reallen * 2 ? len : arr->reallen * 2);
	arr->data = xrealloc(arr->data, arr->reallen*sizeof(bytecode_t));
	if(!arr->data) 
	{ /* out of memory? */
	    return 0;
	}
    }
    
    return 1;
}

/*
 * functions of the form bc_XXX_generate have the following properties:
 * on success they return an int that corresponds to the next empty location
 * for code, and on failure they return -1.
 *
 *  they will take a  bytecode_info_t as a parameter and modify it by
 *  making it larger and adding more bytecommands in the pass 1 form
 */

/* given a location and a string list, compile it into almost-flat form.
 * <list len> <string len><string ptr><string len><string ptr> etc... */
static int bc_stringlist_generate(int codep, bytecode_info_t *retval,
				  stringlist_t *sl) 
{
    int len_codep = codep;
    int strcount = 0;
    stringlist_t *cur;
    
    codep++;

    /* Bounds check the string list length */
    if(!atleast(retval,codep+1)) 
	return -1;

    for(cur=sl; cur; cur=cur->next) 
    {
	strcount++;
	assert((cur->s)!=NULL);
	
	/* Bounds check for each string before we allocate it */
	if(!atleast(retval,codep+2)) 
	    return -1;

	retval->data[codep++].len = strlen(cur->s);
	retval->data[codep++].str = cur->s;
    }
    
    retval->data[len_codep].listlen = strcount;
    return codep;
}


/* write a list of tests into almost-flat form, starting at codep.
 * returns the next code location, -1 on error. */

/* <list len> <next test ptr> <test ...> <next test ptr> <test ...> ... */
static int bc_testlist_generate(int codep, bytecode_info_t *retval, 
				testlist_t *tl) 
{
    int len_codep = codep;
    int testcount = 0;
    testlist_t *cur;
    
    codep++;

    /* Bounds check the test list length */
    if(!atleast(retval,codep+1)) 
	return -1;
       
    for(cur=tl; cur; cur=cur->next) {
	int oldcodep = codep;

	/* Make room for tail marker */
	if(!atleast(retval,codep+1)) 
	    return -1;

	testcount++;
	codep = bc_test_generate(codep+1, retval, cur->t);

	retval->data[oldcodep].jump = codep;
    }

    retval->data[len_codep].listlen = testcount;
        
    return codep;
}
/* output a relation into almost-flat form at codep.
 * returns new codep on success, -1 on failure. */
static int bc_relation_generate(int codep, bytecode_info_t *retval, int relat)
{
    if (!atleast(retval, codep + 1)) return -1;
    switch (relat)
    {
    case GT:
	retval->data[codep++].value= B_GT;
	break;
    case GE:
	retval->data[codep++].value= B_GE;
	break; 
    case LT:
	retval->data[codep++].value= B_LT;
	break;
    case LE:
	retval->data[codep++].value= B_LE;
	break;
    case EQ:
	retval->data[codep++].value= B_EQ;
	break;
    case NE:
	retval->data[codep++].value= B_NE;
	break;
    default:
	/* comparator has no relational field */
	retval->data[codep++].value=  -1;
	break;
    }
    return codep;
}
/* writes a single comparator into almost-flat form starting at codep.
 * will always write out 3 words
 * returns the next code location or -1 on error. */
static int bc_comparator_generate(int codep, bytecode_info_t *retval,
                                  int comptag, int relat,
                                  const char *comparator)
{
    assert(retval != NULL);

    /* comptag */
    if (!atleast(retval, codep + 1)) return -1;

    switch (comptag) {
    case IS:
        retval->data[codep++].value = B_IS;
        break;
    case CONTAINS:
        retval->data[codep++].value = B_CONTAINS;
        break;
    case MATCHES:
        retval->data[codep++].value = B_MATCHES;
        break;
#ifdef ENABLE_REGEX
    case REGEX:
        retval->data[codep++].value = B_REGEX;
        break;
#endif
    case COUNT:
        retval->data[codep++].value = B_COUNT;
        break;
    case VALUE:
        retval->data[codep++].value = B_VALUE;
        break;

    default:
        return -1;
    }
  
    /*relation*/
    codep = bc_relation_generate(codep, retval, relat);
  
    /* comparator (value specified with :comparator) */
    if (!atleast(retval, codep + 1)) return -1;
  
    /* xxx perhaps extend comparator.h to have
       lookup_comp return an index, and then
       lookup_by_index return the actual comparator?
       
       we can then eliminate the comptag above, too. */
    
    if (!strcmp (comparator, "i;octet"))
        retval->data[codep++].value = B_OCTET;
    else if (!strcmp (comparator, "i;ascii-casemap"))
        retval->data[codep++].value = B_ASCIICASEMAP;
    else if (!strcmp (comparator, "i;ascii-numeric"))
        retval->data[codep++].value = B_ASCIINUMERIC;

    return codep;
}



/* writes a single test into almost-flat form starting at codep.
 * returns the next code location or -1 on error. */
static int bc_test_generate(int codep, bytecode_info_t *retval, test_t *t)
{
    if(!retval) return -1;
    switch(t->type) {
    case STRUE: /* BC_TRUE */
	if(!atleast(retval,codep+1)) return -1;
	retval->data[codep++].op = BC_TRUE;
	break;
    case SFALSE:/* BC_FALSE */
	if(!atleast(retval,codep+1)) return -1;
	retval->data[codep++].op = BC_FALSE;
	break;
    case NOT: /* BC_NOT {subtest : test} */
	if(!atleast(retval,codep+1)) return -1;
	retval->data[codep++].op = BC_NOT;
	codep = bc_test_generate(codep, retval, t->u.t);
	if (codep == -1) return -1;
	break;
    case SIZE: /* BC_SIZE (B_OVER | B_UNDER) {size : int} */
	if(!atleast(retval,codep+3)) return -1;
	retval->data[codep++].op = BC_SIZE;
	retval->data[codep++].value = (t->u.sz.t == OVER
				       ? B_OVER : B_UNDER);
	retval->data[codep++].value = t->u.sz.n;
	break;
    case EXISTS:/* BC_EXISTS { headers : string list } */
	if(!atleast(retval,codep+1)) return -1;
	retval->data[codep++].op = BC_EXISTS;
	codep= bc_stringlist_generate(codep, retval, t->u.sl);
	break;
    case ANYOF:/* BC_ANYOF { tests : test list } */
	if(!atleast(retval,codep+1)) return -1;
	retval->data[codep++].op = BC_ANYOF;
	codep=bc_testlist_generate(codep, retval, t->u.tl);
	if (codep == -1) return -1;
	break;
    case ALLOF: /* BC_ALLOF { tests : test list } */
	if(!atleast(retval,codep+1)) return -1;
	retval->data[codep++].op = BC_ALLOF;
	codep= bc_testlist_generate(codep, retval, t->u.tl);
	if (codep == -1) return -1;
	break;
    case HEADER:
	/* BC_HEADER { c: comparator } { headers : string list }
	   { patterns : string list } 
	*/
      
	if(!atleast(retval,codep + 1)) return -1;
	retval->data[codep++].op = BC_HEADER;
      
	/* comparator */
	codep = bc_comparator_generate(codep, retval,
				       t->u.h.comptag,
				       t->u.h.relation,
				       t->u.h.comparator);
	if (codep == -1) return -1;
      
	/* headers */
	codep = bc_stringlist_generate(codep, retval, t->u.h.sl);
	if (codep == -1) return -1;
      
	/* pattern */
	codep = bc_stringlist_generate(codep, retval, t->u.h.pl);
	if (codep == -1) return -1;
	break;
    case ADDRESS:
    case ENVELOPE:
	/* (BC_ADDRESS | BC_ENVELOPE) {c : comparator} 
	   (B_ALL | B_LOCALPART | ...) { header : string list }
	   { pattern : string list } */
      
	if(!atleast(retval,codep+1)) return -1;
      
	retval->data[codep++].op = (t->type == ADDRESS)
	    ? BC_ADDRESS : BC_ENVELOPE;
            
	codep = bc_comparator_generate(codep, retval,t->u.ae.comptag,
				       t->u.ae.relation, 
				       t->u.ae.comparator);
	if (codep == -1) return -1;

	if(!atleast(retval,codep+1)) return -1;

	/*address part*/
	switch(t->u.ae.addrpart) {
	case ALL:
	    retval->data[codep++].value = B_ALL;
	    break;
	case LOCALPART:
	    retval->data[codep++].value = B_LOCALPART;
	    break;
	case DOMAIN:
	    retval->data[codep++].value = B_DOMAIN;
	    break;
	case USER:
	    retval->data[codep++].value = B_USER;
	    break;
	case DETAIL:
	    retval->data[codep++].value = B_DETAIL;
	    break;
	default:
	    return -1;
	}

	/*headers*/
	codep = bc_stringlist_generate(codep, retval, t->u.ae.sl);
	if (codep == -1) return -1;

	/*patterns*/
	codep = bc_stringlist_generate(codep, retval, t->u.ae.pl);
	if (codep == -1) return -1;
     
	break;
    case BODY:
	/* BC_BODY {c : comparator} (B_RAW | B_TEXT | ...)
	   { content-types : stringlist }
	   { offset : int }
	   { pattern : string list } */
      
	if(!atleast(retval,codep+1)) return -1;
      
	retval->data[codep++].op = BC_BODY;
            
	codep = bc_comparator_generate(codep, retval,t->u.b.comptag,
				       t->u.b.relation, 
				       t->u.b.comparator);
	if (codep == -1) return -1;

	if(!atleast(retval,codep+2)) return -1;

	/*transform*/
	switch(t->u.b.transform) {
	case RAW:
	    retval->data[codep++].value = B_RAW;
	    break;
	case TEXT:
	    retval->data[codep++].value = B_TEXT;
	    break;
	case CONTENT:
	    retval->data[codep++].value = B_CONTENT;
	    break;
	default:
	    return -1;
	}

	/*offset*/
	retval->data[codep++].value = t->u.b.offset;

	/*content-types*/
	codep = bc_stringlist_generate(codep, retval, t->u.b.content_types);
	if (codep == -1) return -1;

	/*patterns*/
	codep = bc_stringlist_generate(codep, retval, t->u.b.pl);
	if (codep == -1) return -1;
     
	break;
    default:
	return -1;
      
    }
    return codep;
}


/* generate a not-quite-flattened bytecode */
/* returns address of next instruction or -1 on error*/
/* needs current instruction, buffer for the code, and a current parse tree */
/* sieve is cool because everything is immediate! */
static int bc_action_generate(int codep, bytecode_info_t *retval,
			      commandlist_t *c) 
{
    int jumploc,baseloc;

    if(!retval) return -1;
    if (c==NULL)
    {
	if(!atleast(retval,codep+1)) return -1;
	retval->data[codep++].op = B_NULL;
    }
    else
    {
	do {
	    switch(c->type) {
	    case STOP:
		/* STOP (no arguments) */
		if(!atleast(retval,codep+1)) return -1;
		retval->data[codep++].op = B_STOP;
		break;
	    case DISCARD:
		/* DISCARD (no arguments) */
		if(!atleast(retval,codep+1)) return -1;
		retval->data[codep++].op = B_DISCARD;
		break;
	    case KEEP:
		/* KEEP (no arguments) */
		if(!atleast(retval,codep+1)) return -1;
		retval->data[codep++].op = B_KEEP;
		break;
	    case MARK:
		/* MARK (no arguments) */
		if(!atleast(retval,codep+1)) return -1;
		retval->data[codep++].op = B_MARK;
		break;
	    case UNMARK:
		/* UNMARK (no arguments) */
		if(!atleast(retval,codep+1)) return -1;
		retval->data[codep++].op = B_UNMARK;
		break;

	    case RETURN:
		/* RETURN (no arguments) */
		if(!atleast(retval,codep+1)) return -1;
		retval->data[codep++].op = B_RETURN;
		break;

	    case DENOTIFY:
		/* DENOTIFY  */
		if(!atleast(retval,codep+6)) return -1;
		retval->data[codep++].op = B_DENOTIFY;
		switch(c->u.d.priority) {
		case LOW:
		    retval->data[codep++].value = B_LOW;
		    break;
		case NORMAL:
		    retval->data[codep++].value = B_NORMAL;
		    break;
		case HIGH:
		    retval->data[codep++].value = B_HIGH;
		    break;
		case ANY:
		    retval->data[codep++].value = B_ANY;
		    break;
		default:
		    return -1;
		}
		switch(c->u.d.comptag) {
		case IS:
		    retval->data[codep++].value = B_IS;
		    break;
		case CONTAINS:
		    retval->data[codep++].value = B_CONTAINS;
		    break;
		case MATCHES:
		    retval->data[codep++].value = B_MATCHES;
		    break;
#ifdef ENABLE_REGEX
		case REGEX:
		    retval->data[codep++].value = B_REGEX;
		    break;
#endif
		case ANY:
		    retval->data[codep++].value = B_ANY;
		    break; 
		default:
		    return -1;
		}
		codep = bc_relation_generate(codep, retval, c->u.d.relation);
	
		if(c->u.d.pattern)
		{
		    retval->data[codep++].len = strlen(c->u.d.pattern);
		    retval->data[codep++].str = c->u.d.pattern;
		} else {
		    retval->data[codep++].len = -1;
		    retval->data[codep++].str = NULL;
		}

		break;
	    case REJCT:
		/* REJECT (STRING: len + dataptr) */
		if(!atleast(retval,codep+3)) return -1;
		retval->data[codep++].op = B_REJECT;
		retval->data[codep++].len = strlen(c->u.str);
		retval->data[codep++].str = c->u.str;
		break;
	    case FILEINTO:
		/* FILEINTO
		   VALUE copy
		   STRING folder
		*/
		if(!atleast(retval,codep+4)) return -1;
		retval->data[codep++].op = B_FILEINTO;
		retval->data[codep++].value = c->u.f.copy;
		retval->data[codep++].len = strlen(c->u.f.folder);
		retval->data[codep++].str = c->u.f.folder;
		break;
	    case REDIRECT:
		/* REDIRECT
		   VALUE copy
		   STRING address
		*/
		if(!atleast(retval,codep+4)) return -1;
		retval->data[codep++].op = B_REDIRECT;
		retval->data[codep++].value = c->u.r.copy;
		retval->data[codep++].len = strlen(c->u.r.address);
		retval->data[codep++].str = c->u.r.address;
		break;
	    case ADDFLAG:
		/* ADDFLAG stringlist */
		if(!atleast(retval,codep+1)) return -1;
		retval->data[codep++].op = B_ADDFLAG;
		codep = bc_stringlist_generate(codep,retval,c->u.sl);

		if(codep == -1) return -1;
		break;
	    case SETFLAG:
		/* SETFLAG stringlist */
		if(!atleast(retval,codep+1)) return -1;
		retval->data[codep++].op = B_SETFLAG;
		codep = bc_stringlist_generate(codep,retval,c->u.sl);

		if(codep == -1) return -1;
		break;
	    case REMOVEFLAG:
		/* REMOVEFLAG stringlist */
		if(!atleast(retval,codep+1)) return -1;
		retval->data[codep++].op = B_REMOVEFLAG;
		codep = bc_stringlist_generate(codep,retval,c->u.sl);

		if(codep == -1) return -1;
		break;
	    case NOTIFY:
		/* NOTIFY 
		   (STRING: len + dataptr)
		   (STRING: len + dataptr)
		   stringlist
		   (STRING: len + dataptr)
		   (STRING: len + dataptr)
		   method/id /options list/priority/message 
		*/
			
		if(!atleast(retval,codep+5)) return -1;
		retval->data[codep++].op = B_NOTIFY;
		
		retval->data[codep++].len = strlen(c->u.n.method);
		retval->data[codep++].str = c->u.n.method;
				
		if (c->u.n.id)
		{
		    retval->data[codep++].len = strlen(c->u.n.id);
		    retval->data[codep++].str = c->u.n.id;
		}
		else
		{
		    retval->data[codep++].len = -1;
		    retval->data[codep++].str = NULL;
		}
		
		codep = bc_stringlist_generate(codep,retval,c->u.n.options);
		if(codep == -1) return -1;

		if(!atleast(retval,codep+3)) return -1;

		switch(c->u.n.priority) {
		case LOW:
		    retval->data[codep++].value = B_LOW;
		    break;
		case NORMAL:
		    retval->data[codep++].value = B_NORMAL;
		    break;
		case HIGH:
		    retval->data[codep++].value = B_HIGH;
		    break;
		case ANY:
		    retval->data[codep++].value = B_ANY;
		    break;
		default:
		    return -1;
		}
		
		retval->data[codep++].len = strlen(c->u.n.message);
		retval->data[codep++].str = c->u.n.message;
		break;
	    case VACATION:
		/* VACATION
		   STRINGLIST addresses
		   STRING subject (if len is -1, then subject was NULL)
		   STRING message (again, len == -1 means message was NULL)
		   VALUE days
		   VALUE mime
		   STRING from (if len is -1, then from was NULL)
		   STRING handle (again, len == -1 means handle was NULL)
		*/

		if(!atleast(retval,codep+1)) return -1;
		retval->data[codep++].op = B_VACATION;
	    
		codep = bc_stringlist_generate(codep,retval,c->u.v.addresses);
		if (codep == -1) return -1;

		if (!atleast(retval,codep+2)) return -1;
		if(c->u.v.subject) {
		    retval->data[codep++].len = strlen(c->u.v.subject);
		    retval->data[codep++].str = c->u.v.subject;
		} else {
		    retval->data[codep++].len = -1;
		    retval->data[codep++].str = NULL;
		}

		if (!atleast(retval,codep+2)) return -1;
		if(c->u.v.message) {
		    retval->data[codep++].len = strlen(c->u.v.message);
		    retval->data[codep++].str = c->u.v.message;
		} else {
		    retval->data[codep++].len = -1;
		    retval->data[codep++].str = NULL;
		}

		if (!atleast(retval,codep+2)) return -1;
		retval->data[codep++].value = c->u.v.days;
		retval->data[codep++].value = c->u.v.mime;
	    
		if (!atleast(retval,codep+2)) return -1;
		if(c->u.v.from) {
		    retval->data[codep++].len = strlen(c->u.v.from);
		    retval->data[codep++].str = c->u.v.from;
		} else {
		    retval->data[codep++].len = -1;
		    retval->data[codep++].str = NULL;
		}

		if (!atleast(retval,codep+2)) return -1;
		if(c->u.v.handle) {
		    retval->data[codep++].len = strlen(c->u.v.handle);
		    retval->data[codep++].str = c->u.v.handle;
		} else {
		    retval->data[codep++].len = -1;
		    retval->data[codep++].str = NULL;
		}


		if(codep == -1) return -1;
		break;
	    case INCLUDE:
		/* INCLUDE
		   VALUE location
		   STRING filename */
		if(!atleast(retval,codep+4)) return -1;
		retval->data[codep++].op = B_INCLUDE;

		switch(c->u.inc.location) {
		case PERSONAL:
		    retval->data[codep++].value = B_PERSONAL;
		    break;
		case GLOBAL:
		    retval->data[codep++].value = B_GLOBAL;
		    break;
		default:
		    return -1;
		}
		
		retval->data[codep++].len = strlen(c->u.inc.script);
		retval->data[codep++].str = c->u.inc.script;
		break;
	    case IF:
	    {
		int jumpVal; 	    
		/* IF
		   (int: begin then block)
		   (int: end then block/begin else block)
		   (int:end else block) (-1 if no else block)
		   (test)
		   (then block)
		   (else block)(optional)
		*/
		baseloc = codep;
	    
		/* Allocate operator + jump table offsets */
		if(!atleast(retval,codep+4)) return -1;
		
		jumploc = codep+4;
		retval->data[codep++].op = B_IF;
		    
		/* begining of then  code */
		jumpVal= bc_test_generate(jumploc,retval,c->u.i.t);
		if(jumpVal == -1) 
		    return -1;
		else {
		    retval->data[codep].jump = jumpVal;
		    codep++;
		}
	    
		/* find then code and offset to else code,
		 * we want to write this code starting at the offset we
		 * just found */
	
		jumpVal= bc_action_generate(jumpVal,retval, c->u.i.do_then);
		if(jumpVal == -1) 
		    return -1;
		else 
		    retval->data[codep].jump = jumpVal;
		
		codep++;
		/* write else code if its there*/
		if(c->u.i.do_else) {
	
		    jumpVal= bc_action_generate(jumpVal,retval, c->u.i.do_else);
		    if(jumpVal == -1) 
		    {
			return -1;
		    } else 
		    {
			retval->data[codep].jump = jumpVal;
		    }
		    
		    /* Update code pointer to end of else code */
		    codep = retval->data[codep].jump;
		} else {
		    /*there is no else block, so its -1*/
		    retval->data[codep].jump = -1;
		    /* Update code pointer to end of then code */
		    codep = retval->data[codep-1].jump;
		}
	    
		break;
	    }
	    default:
		/* no such action known */
		return -1;
	    }
	  
	    /* generate from next command */
	    c = c->next;
	} while(c);
    }
    /*scriptend may be updated before the end, but it will be updated at the end, which is what matters.*/
    retval->scriptend=codep;
    return codep;
   
}



/* Entry point to the bytecode emitter module */	
int sieve_generate_bytecode(bytecode_info_t **retval, sieve_script_t *s) 
{
    commandlist_t *c;

    if(!retval) return -1;
    if(!s) return -1;
    c = s->cmds;
    /* if c is NULL, it is handled in bc_action_generate and a script
       with only BC_NULL is returned
    */

    
    *retval = xmalloc(sizeof(bytecode_info_t));
    if(!(*retval)) return -1;

    memset(*retval, 0, sizeof(bytecode_info_t));

    return bc_action_generate(0, *retval, c);
}


void sieve_free_bytecode(bytecode_info_t **p) 
{
    if(!p || !*p) return;
    if((*p)->data) free((*p)->data);
    free(*p);
    *p = NULL;
}
 
