bird/filter/config.Y
Martin Mares e0f2e42f4f A couple of filter tweaks:
o  Introduced struct filter which serves as an external reference
      to filter. Using struct symbol for this is unwise since it doesn't
      allow extra information attached to the filter and it also forces
      all filters to be named.
   o  Implemented config rule 'filter' which matches either named filter
      or an embedded unnamed filter (`{ <filter> }').
   o  Fixed totally bogus comment at the top of filter.h.
   o  Added a missing prototype for f_run() to filter.h.
1999-03-17 14:29:39 +00:00

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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