switch() { } done right.

3 files changed, 42 insertions, 60 deletions

diff --git a/filter/config.Y b/filter/config.Y
index 9385483..d5a9dca 100644
--- a/filter/config.Y
+++ b/filter/config.Y
@@ -11,7 +11,6 @@
 	FIXME: whole system of paths, path ~ string, path.prepend(), path.originate
 	FIXME: create community lists
 	FIXME: access to dynamic attributes
-	FIXME: make case faster
  */
 
 CF_HDR
@@ -37,10 +36,10 @@ CF_KEYWORDS(FUNCTION, PRINT, PRINTN, CONST,
 	FILTER
 	)
 
-%type <x> term block cmds cmd function_body ifthen constant print_one print_list var_list switch_body
+%type <x> term block cmds cmd function_body ifthen constant print_one print_list var_list
 %type <f> filter filter_body
 %type <i> type break_command pair
-%type <e> set_item set_items
+%type <e> set_item set_items switch_body
 %type <v> set_atom prefix prefix_s ipa
 %type <s> decls function_params 
 
@@ -191,6 +190,20 @@ set_items:
  | set_items ',' set_item { $$ = $3; $$->left = $1; }
  ;
 
+/* 2 shift/reduce conflicts here. Curable by replacing cmds with block which breaks syntax */
+switch_body: /* EMPTY */ { $$ = NULL; }
+ | set_item ':' cmds switch_body {
+     $$ = $1;
+     $$->data = $3;
+     $$->left = $4;
+   }
+ | ELSE ':' cmds {
+     $$ = f_new_tree(); 
+     $$->from.type = T_VOID; 
+     $$->to.type = T_VOID;
+     $$->data = $3;
+   }
+ ;
 
 constant:
    CONST '(' expr ')' { $$ = f_new_inst(); $$->code = 'c'; $$->a1.i = T_INT; $$->a2.i = $3; }
@@ -286,23 +299,6 @@ var_list: term {
    }
  ;
 
-/* 2 shift/reduce conflicts here. Curable by replacing cmds with block which breaks syntax */
-switch_body: /* EMPTY */ { $$ = NULL; }
- | term ':' cmds switch_body {
-     $$ = f_new_inst();
-     $$->code = 'of';
-     $$->a1.p = $1;
-     $$->a2.p = $3;
-     $$->next = $4;
-   }
- | ELSE ':' cmds {
-     $$ = f_new_inst();
-     $$->code = 'el';
-     $$->a1.p = NULL;
-     $$->a2.p = $3;
-   }
- ;
-
 cmd:
    ifthen { 
      $$ = $1;
@@ -346,9 +342,9 @@ cmd:
    }
  | CASE term '{' switch_body '}' {
       $$ = f_new_inst();
-      $$->code = 'sw';
+      $$->code = 'SW';
       $$->a1.p = $2;
-      $$->a2.p = $4;
+      $$->a2.p = build_tree( $4 );
    }
  ;
 
diff --git a/filter/filter.c b/filter/filter.c
index f6b2d4b..dc8235e 100644
--- a/filter/filter.c
+++ b/filter/filter.c
@@ -54,6 +54,13 @@ struct f_inst *startup_func = NULL;
 int
 val_compare(struct f_val v1, struct f_val v2)
 {
+  if ((v1.type == T_VOID) && (v2.type == T_VOID))
+    return 0;
+  if (v1.type == T_VOID)	/* Hack for else */
+    return -1;
+  if (v2.type == T_VOID)
+    return 1;
+
   if (v1.type != v2.type)
     return CMP_ERROR;
   switch (v1.type) {
@@ -64,7 +71,7 @@ val_compare(struct f_val v1, struct f_val v2)
     return 1;
   case T_IP:
     return ipa_compare(v1.val.ip, v2.val.ip);
-  default: return CMP_ERROR;
+  default: { printf( "Error comparing\n" ); return CMP_ERROR; }
   }
 }
 
@@ -115,40 +122,6 @@ static struct rte **f_rte;
 static struct f_val interpret(struct f_inst *what);
 
 static struct f_val
-interpret_switch(struct f_inst *what, struct f_val control)
-{
-  struct f_val this, res;
-  int i;
-  res.type = T_VOID;
-
-  if (!what)
-    return res;
-
-  switch(what->code) {
-  case 'el':
-    return interpret(what->a2.p);
-
-  case 'of':
-    this = interpret(what->a1.p);
-    i = val_compare(control, this);
-    if (!i)
-      return interpret(what->a2.p);
-    if (i==CMP_ERROR) {
-      i = val_in_range(control, this);
-      if (i==1)
-	return interpret(what->a2.p);
-      if (i==CMP_ERROR)
-	runtime( "incompatible types in case" );
-    }
-    break;
-    
-  default:
-    bug( "This can not happen (%x)\n", what->code );
-  }
-  return interpret_switch(what->next, control);
-}
-
-static struct f_val
 interpret(struct f_inst *what)
 {
   struct symbol *sym;
@@ -309,9 +282,22 @@ interpret(struct f_inst *what)
     ONEARG;
     res = interpret(what->a2.p);
     break;
-  case 'sw': /* SWITCH alias CASE */
+  case 'SW':
     ONEARG;
-    interpret_switch(what->a2.p, v1);
+    {
+      struct f_tree *t = find_tree(what->a2.p, v1);
+      if (!t) {
+	v1.type = T_VOID;
+	t = find_tree(what->a2.p, v1);
+	if (!t) {
+	  printf( "No else statement?\n ");
+	  break;
+	}
+      }	
+      if (!t->data)
+	die( "Impossible: no code associated!\n" );
+      return interpret(t->data);
+    }
     break;
   case 'iM': /* IP.MASK(val) */
     TWOARGS_C;
diff --git a/filter/tree.c b/filter/tree.c
index ea1f18f..43888f0 100644
--- a/filter/tree.c
+++ b/filter/tree.c
@@ -73,7 +73,7 @@ struct f_tree *
 find_tree(struct f_tree *t, struct f_val val)
 {
   if (!t)
-    return 0;
+    return NULL;
   if ((val_compare(t->from, val) != 1) &&
       (val_compare(t->to, val) != -1))
     return t;