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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 "char.h"
#include "error.h"
#include "xalloc.h"
/*
WHITE SPACE CHARACTERS
This variable holds all the white space characters.
*/
letter *white_space = NULL ;
/*
LEXICAL PASS REPRESENTATIONS
These variables describe the various lexical passes.
*/
static character passes [2] = {
{ LAST_LETTER, NULL, NULL, NULL },
{ LAST_LETTER, NULL, NULL, NULL }
} ;
character *pre_pass = passes ;
character *main_pass = passes + 1 ;
/*
ALLOCATE A NEW CHARACTER
This routine allocates a new character with value c.
*/
static character *new_char
PROTO_N ( ( c ) )
PROTO_T ( letter c )
{
character *p ;
static int chars_left = 0 ;
static character *chars_free = NULL ;
if ( chars_left == 0 ) {
chars_left = 100 ;
chars_free = xmalloc_nof ( character, chars_left ) ;
}
p = chars_free + ( --chars_left ) ;
p->ch = c ;
p->defn = NULL ;
p->cond = NULL ;
p->opt = NULL ;
p->next = NULL ;
return ( p ) ;
}
/*
ADD A CHARACTER
This routine adds the string s (defined using data) to the lexical
pass p.
*/
void add_char
PROTO_N ( ( p, s, data ) )
PROTO_T ( character *p X letter *s X char **data )
{
character *q ;
letter c = *s ;
if ( p->next == NULL ) {
q = new_char ( c ) ;
p->next = q ;
} else {
character *r = NULL ;
for ( q = p->next ; q && ( q->ch < c ) ; q = q->opt ) r = q ;
if ( q && q->ch == c ) {
/* already exists */
} else {
q = new_char ( c ) ;
if ( r == NULL ) {
q->opt = p->next ;
p->next = q ;
} else {
q->opt = r->opt ;
r->opt = q ;
}
}
}
if ( c == LAST_LETTER ) {
if ( q->defn ) {
error ( ERROR_SERIOUS,
"String for '%s' has already been defined to give '%s'",
data [0], q->defn ) ;
}
q->defn = data [0] ;
q->args = data [1] ;
q->cond = data [2] ;
} else {
add_char ( q, s + 1, data ) ;
}
return ;
}
/*
ARRAY OF ALL GROUPS
This array gives all the character groups.
*/
char_group groups [ MAX_GROUPS ] ;
int no_groups = 0 ;
/*
CREATE A NEW GROUP
This routine creates a new character group with name nm and
definition s.
*/
void make_group
PROTO_N ( ( nm, s ) )
PROTO_T ( char *nm X letter *s )
{
int i, n = no_groups ;
for ( i = 0 ; i < n ; i++ ) {
if ( streq ( nm, groups [i].name ) ) {
error ( ERROR_SERIOUS, "Group '%s' already defined", nm ) ;
return ;
}
}
if ( n >= MAX_GROUPS ) {
error ( ERROR_SERIOUS, "Too many groups defined (%d)", n ) ;
return ;
}
groups [n].name = nm ;
groups [n].defn = s ;
no_groups = n + 1 ;
return ;
}
/*
IS A LETTER IN A GROUP?
This routine checks whether the letter c is in the list p.
*/
int in_group
PROTO_N ( ( p, c ) )
PROTO_T ( letter *p X letter c )
{
letter a ;
if ( p == NULL ) return ( 0 ) ;
while ( a = *( p++ ), a != LAST_LETTER ) {
if ( a == c ) {
return ( 1 ) ;
} else if ( a == WHITE_LETTER ) {
if ( in_group ( white_space, c ) ) return ( 1 ) ;
} else if ( a >= GROUP_LETTER ) {
int n = ( int ) ( a - GROUP_LETTER ) ;
if ( in_group ( groups [n].defn, c ) ) return ( 1 ) ;
}
}
return ( 0 ) ;
}
/*
FIND AN ESCAPE SEQUENCE
This routine finds the character corresponding to the escape sequence c.
*/
letter find_escape
PROTO_N ( ( c ) )
PROTO_T ( int c )
{
letter a ;
switch ( c ) {
case 'n' : a = '\n' ; break ;
case 't' : a = '\t' ; break ;
case 'v' : a = '\v' ; break ;
case 'f' : a = '\f' ; break ;
case 'r' : a = '\r' ; break ;
case '?' : a = '?' ; break ;
case '"' : a = '"' ; break ;
case '[' : a = '[' ; break ;
case '\\' : a = '\\' ; break ;
case '\'' : a = '\'' ; break ;
case 'e' : a = EOF_LETTER ; break ;
default : {
error ( ERROR_SERIOUS, "Unknown escape sequence, '\\%c'",
( unsigned char ) c ) ;
a = ( letter ) ( c & 0xff ) ;
break ;
}
}
return ( a ) ;
}
/*
TRANSLATE A STRING INTO A CHARACTER STRING
This routine translates the string s into an array of letters.
*/
letter *make_string
PROTO_N ( ( s ) )
PROTO_T ( char *s )
{
int i = 0, n = ( int ) strlen ( s ) ;
letter *p = xmalloc_nof ( letter, n + 1 ) ;
while ( *s ) {
letter a ;
char c = *( s++ ) ;
if ( c == '\\' ) {
c = *( s++ ) ;
a = find_escape ( c ) ;
} else if ( c == '[' ) {
int j ;
size_t glen ;
char *gnm = s ;
while ( *s && *s != ']' ) s++ ;
glen = ( size_t ) ( s - gnm ) ;
if ( *s ) {
s++ ;
} else {
error ( ERROR_SERIOUS,
"Unterminated character group name, '%s'", gnm ) ;
}
for ( j = 0 ; j < no_groups ; j++ ) {
if ( strncmp ( gnm, groups [j].name, glen ) == 0 ) {
a = GROUP_LETTER + j ;
break ;
}
}
if ( j == no_groups ) {
if ( strncmp ( gnm, "white", glen ) == 0 ) {
a = WHITE_LETTER ;
} else {
error ( ERROR_SERIOUS, "Unknown character group, '%.*s'",
( int ) glen, gnm ) ;
a = '?' ;
}
}
SET ( a ) ;
} else {
a = ( letter ) ( c & 0xff ) ;
}
p [i] = a ;
i++ ;
}
p [i] = LAST_LETTER ;
return ( p ) ;
}
/*
LIST OF ALL KEYWORDS
This variable gives a list of all the keywords.
*/
keyword *keywords = NULL ;
/*
ADD A KEYWORD
This routine adds the keyword nm with its associated data to the list
of all keywords.
*/
void add_keyword
PROTO_N ( ( nm, data ) )
PROTO_T ( char *nm X char **data )
{
static int keywords_left = 0 ;
static keyword *keywords_free = NULL ;
keyword *p = keywords, *q = NULL ;
while ( p ) {
int c = strcmp ( nm, p->name ) ;
if ( c == 0 ) {
error ( ERROR_SERIOUS, "Keyword '%s' already defined", nm ) ;
return ;
}
if ( c < 0 ) break ;
q = p ;
p = p->next ;
}
if ( keywords_left == 0 ) {
keywords_left = 100 ;
keywords_free = xmalloc_nof ( keyword, keywords_left ) ;
}
p = keywords_free + ( --keywords_left ) ;
p->name = nm ;
p->defn = data [0] ;
p->args = data [1] ;
p->cond = data [2] ;
p->done = 0 ;
if ( q == NULL ) {
p->next = keywords ;
keywords = p ;
} else {
p->next = q->next ;
q->next = p ;
}
return ;
}