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/*
Crown Copyright (c) 1997
This TenDRA(r) Computer Program is subject to Copyright
owned by the United Kingdom Secretary of State for Defence
acting through the Defence Evaluation and Research Agency
(DERA). It is made available to Recipients with a
royalty-free licence for its use, reproduction, transfer
to other parties and amendment for any purpose not excluding
product development provided that any such use et cetera
shall be deemed to be acceptance of the following conditions:-
(1) Its Recipients shall ensure that this Notice is
reproduced upon any copies or amended versions of it;
(2) Any amended version of it shall be clearly marked to
show both the nature of and the organisation responsible
for the relevant amendment or amendments;
(3) Its onward transfer from a recipient to another
party shall be deemed to be that party's acceptance of
these conditions;
(4) DERA gives no warranty or assurance as to its
quality or suitability for any purpose and DERA accepts
no liability whatsoever in relation to any use to which
it may be put.
*/
#include "config.h"
#include "types.h"
#include "enc_types.h"
#include "bitstream.h"
#include "encode.h"
#include "high.h"
#include "names.h"
#include "table.h"
#include "tdf.h"
#include "utility.h"
/*
ENCODE AN EXTENDED VALUE
The extended value n is encoded in b bits on the bitstream p.
*/
void enc_bits_extn
PROTO_N ( ( p, b, n ) )
PROTO_T ( bitstream *p X int b X long n )
{
long m = ( ( 1 << b ) - 1 ) ;
if ( n == 0 ) fatal_error ( "Can't encode 0 as an extended value" ) ;
while ( n > m ) {
enc_bits ( p, b, ( long ) 0 ) ;
n -= m ;
}
enc_bits ( p, b, n ) ;
return ;
}
/*
AUXILIARY TDF INTEGER ENCODING ROUTINE
The value n is encoded as a series of octal digits into the
bitstream p.
*/
static void enc_tdf_int_aux
PROTO_N ( ( p, n ) )
PROTO_T ( bitstream *p X long n )
{
unsigned long m = ( unsigned long ) n ;
if ( m >= 8 ) enc_tdf_int_aux ( p, ( long ) ( m >> 3 ) ) ;
enc_bits ( p, 4, ( long ) ( m & 7 ) ) ;
return ;
}
/*
ENCODE A TDF INTEGER
The value n is encoded as a TDF integer into the bitstream p.
*/
void enc_tdf_int
PROTO_N ( ( p, n ) )
PROTO_T ( bitstream *p X long n )
{
unsigned long m = ( unsigned long ) n ;
if ( m >= 8 ) enc_tdf_int_aux ( p, ( long ) ( m >> 3 ) ) ;
enc_bits ( p, 4, ( long ) ( ( m & 7 ) | 8 ) ) ;
return ;
}
/*
ENCODE AN ALIGNED STRING
The string s is encoded as an aligned string into the bitstream p.
n is either the length of s, or -1, indicating that strlen should
be used to find the length.
*/
void enc_aligned_string
PROTO_N ( ( p, s, n ) )
PROTO_T ( bitstream *p X char *s X long n )
{
long i ;
if ( n == -1 ) n = ( long ) strlen ( s ) ;
enc_tdf_int ( p, ( long ) 8 ) ;
enc_tdf_int ( p, n ) ;
align_bitstream ( p ) ;
for ( i = 0 ; i < n ; i++ ) {
long c = ( long ) s [i] ;
enc_bits ( p, 8, c ) ;
}
return ;
}
/*
ENCODE AN EXTERNAL NAME
The external name of the construct p is encoded into the bitstream b.
*/
void enc_external
PROTO_N ( ( b, p ) )
PROTO_T ( bitstream *b X construct *p )
{
node *e = p->ename ;
enc_tdf_int ( b, p->encoding ) ;
if ( e->cons->encoding ) {
node *q = e->son ;
if ( q->cons->sortnum == SORT_tdfstring ) {
node *r = q->bro ;
if ( r == null ) {
enc_external_bits ( b, ENC_string_extern ) ;
align_bitstream ( b ) ;
enc_aligned_string ( b, q->cons->name, q->cons->encoding ) ;
} else {
enc_external_bits ( b, ENC_chain_extern ) ;
align_bitstream ( b ) ;
enc_aligned_string ( b, q->cons->name, q->cons->encoding ) ;
enc_node ( b, r ) ;
}
} else {
enc_external_bits ( b, ENC_unique_extern ) ;
align_bitstream ( b ) ;
enc_tdf_int ( b, q->cons->encoding ) ;
for ( q = e->son->son ; q ; q = q->bro ) {
enc_aligned_string ( b, q->cons->name, q->cons->encoding ) ;
}
}
} else {
enc_external_bits ( b, ENC_string_extern ) ;
align_bitstream ( b ) ;
enc_aligned_string ( b, p->name, ( long ) -1 ) ;
}
return ;
}
/*
FIND THE VALUE OF A STRING OF OCTAL DIGITS
The value of the node p, which represents a number, is returned.
*/
static long octval
PROTO_N ( ( p ) )
PROTO_T ( node *p )
{
long n = ( long ) octal_to_ulong ( p->bro->cons->name ) ;
if ( p->cons->encoding ) n = -n ;
return ( n ) ;
}
/*
ENCODE A NODE
The node p is encoded into the bitstream b.
*/
void enc_node
PROTO_N ( ( b, p ) )
PROTO_T ( bitstream *b X node *p )
{
while ( p ) {
construct *q = p->cons ;
switch ( q->sortnum ) {
case SORT_tdfbool : {
/* Encode a bit */
enc_bits ( b, 1, q->encoding ) ;
break ;
}
case SORT_bytestream : {
/* Encode a bytestream */
bitstream *c = new_bitstream () ;
enc_node ( c, p->son ) ;
enc_tdf_int ( b, bitstream_length ( c ) ) ;
join_bitstreams ( b, c ) ;
break ;
}
case SORT_completion : {
/* Encode a completion */
if ( p->son ) enc_node ( b, p->son ) ;
break ;
}
case SORT_small_tdfint : {
/* Encode a small integer */
enc_tdf_int ( b, q->encoding ) ;
break ;
}
case SORT_tdfint : {
/* Encode a number */
char *num = q->name ;
while ( *num ) {
long d = ( long ) ( *num - '0' ) ;
num++ ;
if ( *num == 0 ) d |= 8 ;
enc_bits ( b, 4, d ) ;
}
break ;
}
case SORT_option : {
/* Encode an optional argument */
if ( p->son ) {
enc_bits ( b, 1, ( long ) 1 ) ;
enc_node ( b, p->son ) ;
} else {
enc_bits ( b, 1, ( long ) 0 ) ;
}
break ;
}
case SORT_repeat : {
/* Encode a repeated argument */
enc_list_start ( b ) ;
enc_tdf_int ( b, q->encoding ) ;
if ( p->son ) enc_node ( b, p->son ) ;
break ;
}
case SORT_tdfstring : {
/* Encode a string */
long i, n = q->encoding ;
if ( n == -1 ) {
node *r = p->son ;
long m = octval ( r ) ;
if ( m < 0 ) m = -m ;
r = r->bro->bro ;
n = r->cons->encoding ;
r = r->son ;
enc_tdf_int ( b, m ) ;
enc_tdf_int ( b, n ) ;
for ( i = 0 ; i < n ; i++ ) {
enc_bits ( b, ( int ) m, octval ( r ) ) ;
r = r->bro->bro ;
}
} else {
enc_tdf_int ( b, ( long ) 8 ) ;
enc_tdf_int ( b, n ) ;
for ( i = 0 ; i < n ; i++ ) {
long c = ( long ) q->name [i] ;
enc_bits ( b, 8, c ) ;
}
}
break ;
}
case SORT_unknown : {
/* Encode an unknown bitstream */
fatal_error ( "Can't encode unknown bitstream" ) ;
break ;
}
case SORT_al_tag : {
/* Encode an alignment tag */
long e = q->encoding ;
enc_al_tag_bits ( b, ( int ) e ) ;
if ( e == ENC_make_al_tag ) {
enc_tdf_int ( b, p->son->cons->encoding ) ;
} else {
if ( p->son ) enc_node ( b, p->son ) ;
}
break ;
}
case SORT_label : {
/* Encode a label */
long e = q->encoding ;
enc_label_bits ( b, ( int ) e ) ;
if ( e == ENC_make_label ) {
enc_tdf_int ( b, p->son->cons->encoding ) ;
} else {
if ( p->son ) enc_node ( b, p->son ) ;
}
break ;
}
case SORT_tag : {
/* Encode a tag */
long e = q->encoding ;
enc_tag_bits ( b, ( int ) e ) ;
if ( e == ENC_make_tag ) {
enc_tdf_int ( b, p->son->cons->encoding ) ;
} else {
if ( p->son ) enc_node ( b, p->son ) ;
}
break ;
}
case SORT_token : {
/* Encode a token */
tok_info *info = get_tok_info ( q ) ;
if ( is_high ( info->res ) ) {
enc_token_bits ( b, ENC_token_apply_token ) ;
enc_token_bits ( b, ENC_make_tok ) ;
enc_tdf_int ( b, q->encoding ) ;
enc_tdf_int ( b, ( long ) 0 ) ;
} else {
enc_token_bits ( b, ENC_make_tok ) ;
enc_tdf_int ( b, q->encoding ) ;
}
if ( p->son ) {
if ( p->son->cons != &token_cons ) {
bitstream *c = new_bitstream () ;
enc_node ( c, p->son ) ;
enc_tdf_int ( b, bitstream_length ( c ) ) ;
join_bitstreams ( b, c ) ;
}
} else {
enc_tdf_int ( b, ( long ) 0 ) ;
}
break ;
}
default : {
/* Encode a simple sort */
int bits = sort_encoding [ q->sortnum ] ;
int extn = sort_extension [ q->sortnum ] ;
if ( extn ) {
enc_bits_extn ( b, bits, q->encoding ) ;
} else {
enc_bits ( b, bits, q->encoding ) ;
}
if ( p->son ) enc_node ( b, p->son ) ;
break ;
}
}
p = p->bro ;
}
return ;
}
/*
ENCODE A SORT
*/
static void enc_sort
PROTO_N ( ( b, s ) )
PROTO_T ( bitstream *b X sortname s )
{
if ( is_high ( s ) ) {
int i ;
high_sort *h = high_sorts + high_no ( s ) ;
enc_sort ( b, SORT_token ) ;
enc_sort ( b, h->res ) ;
enc_list_start ( b ) ;
enc_tdf_int ( b, ( long ) h->no_args ) ;
for ( i = 0 ; i < h->no_args ; i++ ) {
enc_sort ( b, h->args [i] ) ;
}
} else {
enc_sortname_bits ( b, s ) ;
}
return ;
}
/*
ALIGNMENT TAG DEFINITION AUXILIARY ENCODING ROUTINE
The definition of the alignment tag p is encoded into the bitstream p.
*/
void enc_aldef
PROTO_N ( ( b, p ) )
PROTO_T ( bitstream *b X construct *p )
{
al_tag_info *info = get_al_tag_info ( p ) ;
enc_al_tagdef_bits ( b, ENC_make_al_tagdef ) ;
enc_tdf_int ( b, p->encoding ) ;
enc_node ( b, info->def ) ;
return ;
}
/*
TAG DECLARATION AUXILIARY ENCODING ROUTINE
The declaration of the tag p is encoded into the bitstream p.
*/
void enc_tagdec
PROTO_N ( ( b, p ) )
PROTO_T ( bitstream *b X construct *p )
{
int m = 0 ;
tag_info *info = get_tag_info ( p ) ;
switch ( info->var ) {
case 0 : m = ENC_make_id_tagdec ; break ;
case 1 : m = ENC_make_var_tagdec ; break ;
case 2 : m = ENC_common_tagdec ; break ;
}
enc_tagdec_bits ( b, m ) ;
enc_tdf_int ( b, p->encoding ) ;
enc_node ( b, info->dec ) ;
return ;
}
/*
TAG DEFINITION AUXILIARY ENCODING ROUTINE
The definition of the tag p is encoded into the bitstream p. Because
of common_tagdef, there may actually be more than one definition.
The number of definitions is returned.
*/
int enc_tagdef
PROTO_N ( ( b, p ) )
PROTO_T ( bitstream *b X construct *p )
{
int n = 0 ;
int m = 0 ;
tag_info *info = get_tag_info ( p ) ;
node *d = info->def ;
switch ( info->var ) {
case 0 : m = ENC_make_id_tagdef ; break ;
case 1 : m = ENC_make_var_tagdef ; break ;
case 2 : m = ENC_common_tagdef ; break ;
}
while ( d ) {
/* Can have multiple definitions */
enc_tagdef_bits ( b, m ) ;
enc_tdf_int ( b, p->encoding ) ;
enc_node ( b, d->son ) ;
d = d->bro ;
n++ ;
}
return ( n ) ;
}
/*
WORK OUT THE NUMBER OF FORMAL ARGUMENTS GIVEN A STRING
*/
static long no_formals
PROTO_N ( ( args ) )
PROTO_T ( char *args )
{
long n = 0 ;
while ( *args ) {
args = find_sortname ( args, ( sortname * ) null ) ;
args++ ;
n = n + 1 ;
}
return ( n ) ;
}
/*
TOKEN DECLARATION AUXILIARY ENCODING ROUTINE
The declaration of the token p is encoded into the bitstream p.
*/
void enc_tokdec
PROTO_N ( ( b, p ) )
PROTO_T ( bitstream *b X construct *p )
{
tok_info *info = get_tok_info ( p ) ;
enc_tokdec_bits ( b, ENC_make_tokdec ) ;
enc_tdf_int ( b, p->encoding ) ;
/* Deal with signature */
if ( info->sig == null ) {
enc_bits ( b, 1, ( long ) 0 ) ;
} else {
enc_node ( b, info->sig ) ;
}
/* Encode token sort */
enc_sort ( b, SORT_token ) ;
/* Encode the token result sort */
enc_sort ( b, info->res ) ;
/* Encode the token argument sorts */
enc_list_start ( b ) ;
if ( info->args ) {
char *q = info->args ;
enc_tdf_int ( b, no_formals ( q ) ) ;
while ( *q ) {
sortname s ;
q = find_sortname ( q, &s ) ;
q++ ;
enc_sort ( b, s ) ;
}
} else {
enc_tdf_int ( b, ( long ) 0 ) ;
}
return ;
}
/*
TOKEN DEFINITION AUXILIARY ENCODING ROUTINE
The definition of the token p is encoded into the bitstream p.
*/
void enc_tokdef
PROTO_N ( ( b, p ) )
PROTO_T ( bitstream *b X construct *p )
{
bitstream *c = new_bitstream () ;
tok_info *info = get_tok_info ( p ) ;
enc_tokdef_bits ( b, ENC_make_tokdef ) ;
enc_tdf_int ( b, p->encoding ) ;
/* Deal with signature */
if ( info->sig == null ) {
enc_bits ( b, 1, ( long ) 0 ) ;
} else {
enc_node ( b, info->sig ) ;
}
/* Encode token definition type */
enc_token_defn_bits ( c, ENC_token_definition ) ;
/* Encode the token result sort */
enc_sort ( c, info->res ) ;
/* Encode the token arguments */
enc_list_start ( c ) ;
if ( info->args ) {
construct **q = info->pars ;
enc_tdf_int ( c, no_formals ( info->args ) ) ;
while ( *q ) {
tok_info *qinfo = get_tok_info ( *q ) ;
enc_sort ( c, qinfo->res ) ;
enc_tdf_int ( c, ( *q )->encoding ) ;
q++ ;
}
} else {
enc_tdf_int ( c, ( long ) 0 ) ;
}
/* Encode the token definition */
enc_node ( c, info->def ) ;
enc_tdf_int ( b, bitstream_length ( c ) ) ;
join_bitstreams ( b, c ) ;
return ;
}