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authorPavel Machek <pavel@ucw.cz>1999-03-08 21:30:06 +0100
committerPavel Machek <pavel@ucw.cz>1999-03-08 21:30:06 +0100
commitb7005824453583d1459b49c5a424b50e2ea9a2c8 (patch)
tree23579261136bbf4a67a5a50789bebb46bce1e7e5 /filter
parent111213f0b66cff8f562f7d9117c9080a9882129e (diff)
downloadbird-b7005824453583d1459b49c5a424b50e2ea9a2c8.tar
bird-b7005824453583d1459b49c5a424b50e2ea9a2c8.zip
Filters are now a tiny bit stronger (if is actually working ;-)
Diffstat (limited to 'filter')
-rw-r--r--filter/config.Y51
-rw-r--r--filter/f-util.c85
-rw-r--r--filter/filter.h19
3 files changed, 128 insertions, 27 deletions
diff --git a/filter/config.Y b/filter/config.Y
index 73a7588..bdaedaa 100644
--- a/filter/config.Y
+++ b/filter/config.Y
@@ -19,7 +19,7 @@ CF_HDR
CF_DECLS
-CF_KEYWORDS(FUNCTION, FILTER, PRINTDEBUG, INT, PRINT)
+CF_KEYWORDS(FUNCTION, FILTER, PRINTDEBUG, INT, PRINT, CONST, VAR, PUTS, DIE, IF)
%type <x> term
%type <x> cmds
@@ -29,7 +29,7 @@ CF_GRAMMAR
CF_ADDTO(conf, function)
function:
FUNCTION SYM '(' ')' '{' cmds '}' {
- extern struct f_instruction *last_func;
+ extern struct f_inst *last_func;
if ($2->class != SYM_VOID) cf_error("Symbol already defined" );
$2->class = SYM_FUNCTION;
$2->def = $6;
@@ -69,13 +69,47 @@ term:
/* EMPTY */ {
$$ = NULL;
}
+ | term '+' term {
+ $$ = f_new_inst();
+ $$->code = '+';
+ $$->arg1 = $1;
+ $$->arg2 = $3;
+ }
+ | IF '(' term ')' '{' cmds '}' {
+ $$ = f_new_inst();
+ $$->code = '?';
+ $$->arg1 = $3;
+ $$->arg2 = $6;
+ }
+ | IF '(' term ')' term {
+ $$ = 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 '=' expr {
+ | VAR '(' SYM ')' {
+ $$ = f_new_inst();
+ switch ($3->class) {
+ case SYM_VARIABLE_INT:
+ $$->code = 'i';
+ $$->arg1 = &($3->aux);
+ break;
+ default:
+ cf_error("Can not use this class of symbol as variable" );
+ }
+ }
+ | CONST '(' expr ')' {
+ $$ = f_new_inst();
+ $$->code = 'c';
+ $$->arg1 = $3;
+ }
+ | SYM '=' term {
$$ = f_new_inst();
printf( "Ook, we'll set value\n" );
if ($1->class != SYM_VARIABLE_INT)
@@ -84,13 +118,22 @@ term:
$$->arg1 = $1;
$$->arg2 = $3;
}
- | PRINT '(' SYM ')' {
+ | PRINT '(' term ')' {
$$ = 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;
+ }
+ | DIE {
+ $$ = f_new_inst();
+ $$->code = '!';
+ }
| PRINTDEBUG {
$$ = f_new_inst();
$$->code = 'D';
diff --git a/filter/f-util.c b/filter/f-util.c
index 66bf5f1..ba74804 100644
--- a/filter/f-util.c
+++ b/filter/f-util.c
@@ -21,33 +21,73 @@
#include "conf/conf.h"
#include "filter/filter.h"
-struct f_instruction *last_func = NULL;
+struct f_inst *last_func = NULL;
-static void
-interpret(struct f_instruction *what)
+#define runtime die
+
+static struct f_val
+interpret(struct f_inst *what)
{
struct symbol *sym;
+ struct f_val v1, v2, res;
+
+ res.type = T_VOID;
if (!what)
- return;
+ return res;
+
switch(what->code) {
case ',':
interpret(what->arg1);
interpret(what->arg2);
break;
+ case '+':
+ v1 = interpret(what->arg1);
+ v2 = interpret(what->arg2);
+ if (v1.type != v2.type)
+ runtime( "Can not operate with values of incompatible types" );
+
+ switch (res.type = v1.type) {
+ case T_VOID: runtime( "Can not operate with values of type void" );
+ case T_INT: res.val.i = v1.val.i + v2.val.i; break;
+ default: runtime( "Usage of unknown type" );
+ }
+ break;
case '=':
+ v1 = interpret(what->arg2);
sym = what->arg1;
- sym->aux = (int) what->arg2;
+ switch (res.type = v1.type) {
+ case T_VOID: runtime( "Can not assign void values" );
+ case T_INT:
+ if (sym->class != SYM_VARIABLE_INT)
+ runtime( "Variable of bad type" );
+ sym->aux = v1.val.i;
+ break;
+ }
+ break;
+ case 'c':
+ res.type = T_INT;
+ res.val.i = (int) what->arg1;
+ break;
+ case 'i':
+ res.type = T_INT;
+ res.val.i = * ((int *) what->arg1);
break;
case 'p':
- sym = what->arg1;
- switch(sym->class) {
- case SYM_VARIABLE_INT:
- printf( "Printing: %d\n", sym->aux );
- break;
- default:
- printf( "Unknown type passed to print\n" );
- break;
+ v1 = interpret(what->arg1);
+ printf( "Printing: " );
+ switch (v1.type) {
+ case T_VOID: printf( "(void)" ); break;
+ case T_INT: printf( "%d", v1.val.i ); break;
+ default: runtime( "Print of variable of unknown type" );
}
+ printf( "\n" );
+ break;
+ case '?':
+ v1 = interpret(what->arg1);
+ if (v1.type != T_INT)
+ runtime( "If requires integer expression" );
+ if (v1.val.i)
+ res = interpret(what->arg2);
break;
case 'D':
printf( "DEBUGGING PRINT\n" );
@@ -55,8 +95,17 @@ interpret(struct f_instruction *what)
case '0':
printf( "No operation\n" );
break;
+ case 'd':
+ printf( "Puts: %s\n", what->arg1 );
+ break;
+ case '!':
+ die( "Filter asked me to die" );
+ default:
+ die( "Unknown insruction %d(%c)", what->code, what->code & 0xff);
}
- interpret(what->next);
+ if (what->next)
+ return interpret(what->next);
+ return res;
}
void
@@ -69,11 +118,11 @@ filters_postconfig(void)
}
}
-struct f_instruction *
+struct f_inst *
f_new_inst(void)
{
- struct f_instruction * ret;
- ret = cfg_alloc(sizeof(struct f_instruction));
+ struct f_inst * ret;
+ ret = cfg_alloc(sizeof(struct f_inst));
ret->code = 0;
ret->arg1 = ret->arg2 = ret->next = NULL;
return ret;
@@ -82,7 +131,7 @@ f_new_inst(void)
int
f_run(struct symbol *filter, struct rte *rtein, struct rte **rteout)
{
- struct f_instruction *inst;
+ struct f_inst *inst;
debug( "Running filter `%s'...", filter->name );
inst = filter->def;
diff --git a/filter/filter.h b/filter/filter.h
index aed2647..e0f4723 100644
--- a/filter/filter.h
+++ b/filter/filter.h
@@ -11,19 +11,28 @@
#include "lib/resource.h"
-/* Lexer */
-
-struct f_instruction {
- struct f_instruction *next; /* Structure is 16 bytes, anyway */
+struct f_inst { /* Instruction */
+ struct f_inst *next; /* Structure is 16 bytes, anyway */
int code;
void *arg1, *arg2;
};
+struct f_val {
+ int type;
+ union {
+ int i;
+ } val;
+};
+
void filters_postconfig(void);
-struct f_instruction *f_new_inst(void);
+struct f_inst *f_new_inst(void);
#define F_ACCEPT 1
#define F_REJECT 2
#define F_MODIFY 3
+#define T_VOID 0
+#define T_INT 1
+#define T_PX 2
+
#endif