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|
/*
* BIRD - filters
*
* Copyright 1998 Pavel Machek
*
* Can be freely distributed and used under the terms of the GNU GPL.
*/
CF_HDR
#include "nest/bird.h"
#include "lib/resource.h"
#include "lib/socket.h"
#include "lib/timer.h"
#include "nest/protocol.h"
#include "nest/iface.h"
#include "nest/route.h"
CF_DECLS
CF_KEYWORDS(FUNCTION, FILTER, PRINTDEBUG, INT, PRINT, CONST, VAR, PUTS, IF,
ACCEPT, REJECT, ERROR, QUITBIRD)
%type <x> term
%type <x> block
%type <x> cmds
%type <f> filter filter_body
CF_GRAMMAR
CF_ADDTO(conf, function)
function:
FUNCTION SYM '(' ')' '{' cmds '}' {
extern struct f_inst *autoexec_func;
if ($2->class != SYM_VOID) cf_error("Symbol already defined" );
$2->class = SYM_FUNCTION;
$2->def = $6;
if (!strcasecmp($2->name, "autoexec"))
autoexec_func = $6;
printf("Hmm, we've got one function here\n");
}
;
CF_ADDTO(conf, filter_def)
filter_def:
FILTER SYM filter_body {
if ($2->class != SYM_VOID) cf_error("Symbol already defined" );
$2->class = SYM_FILTER;
$2->def = $3;
$3->name = $2->name;
printf( "We have new filter defined (%s)\n", $2->name )
}
;
filter_body:
'{' cmds '}' {
struct filter *f = cfg_alloc(sizeof(struct filter));
f->name = NULL;
f->root = $2;
$$ = f;
}
;
filter:
SYM {
if ($1->class != SYM_FILTER) cf_error("No such filter");
$$ = $1->def;
}
| filter_body
;
/* Programs */
cmds:
term {
if ($1) {
$1->next = NULL;
$$ = $1;
} else $$ = NULL;
}
| term ';' cmds {
if ($1) {
$1->next = $3;
$$ = $1;
} else $$ = $3;
}
;
block:
term ';' {
$$=$1;
}
| '{' cmds '}' {
$$=$2;
}
;
term:
/* EMPTY */ {
$$ = NULL;
}
| term '+' term {
$$ = f_new_inst();
$$->code = '+';
$$->arg1 = $1;
$$->arg2 = $3;
}
| IF '(' term ')' block {
$$ = f_new_inst();
$$->code = '?';
$$->arg1 = $3;
$$->arg2 = $5;
}
| INT SYM {
if ($2->class != SYM_VOID) cf_error("Symbol already defined, can not use as variable\n" );
$2->class = SYM_VARIABLE_INT;
printf( "New variable\n" );
$$ = NULL;
}
| SYM {
$$ = f_new_inst();
switch ($1->class) {
case SYM_VARIABLE_INT:
$$->code = 'i';
$$->arg1 = &($1->aux);
break;
default:
cf_error("Can not use this class of symbol as variable" );
}
}
| VAR '(' SYM ')' {
$$ = f_new_inst();
switch ($3->class) {
case SYM_VARIABLE_INT:
$$->code = 'i';
$$->arg1 = &($3->aux);
break;
default:
cf_error("Can not use this class of symbol as variable" );
}
}
| NUM {
$$ = f_new_inst();
$$->code = 'c';
$$->arg1 = $1
}
| CONST '(' expr ')' {
$$ = f_new_inst();
$$->code = 'c';
$$->arg1 = $3;
}
| SYM '=' term {
$$ = f_new_inst();
printf( "Ook, we'll set value\n" );
if ($1->class != SYM_VARIABLE_INT)
cf_error( "You may only set variables\n" );
$$->code = '=';
$$->arg1 = $1;
$$->arg2 = $3;
}
| PRINT '(' term ')' {
$$ = f_new_inst();
printf( "Ook, we'll print something\n" );
$$->code = 'p';
$$->arg1 = $3;
$$->arg2 = NULL;
}
| PUTS '(' TEXT ')' {
$$ = f_new_inst();
$$->code = 'd';
$$->arg1 = $3;
}
| QUITBIRD {
$$ = f_new_inst();
$$->code = '!';
(int) $$->arg1 = F_QUITBIRD;
}
| ACCEPT {
$$ = f_new_inst();
$$->code = '!';
(int) $$->arg1 = F_ACCEPT;
}
| REJECT {
$$ = f_new_inst();
$$->code = '!';
(int) $$->arg1 = F_REJECT;
}
| ERROR {
$$ = f_new_inst();
$$->code = '!';
(int) $$->arg1 = F_ERROR;
}
| PRINTDEBUG {
$$ = f_new_inst();
$$->code = 'D';
$$->arg1 = $$->arg2 = NULL;
}
;
CF_END
|
