Conf: Symbol implementation converted from void pointers to union

... and consted some declarations.

3 files changed, 69 insertions, 44 deletions

diff --git a/conf/cf-lex.l b/conf/cf-lex.l
index 6cc09425..f1b402a0 100644
--- a/conf/cf-lex.l
+++ b/conf/cf-lex.l
@@ -539,11 +539,8 @@ cf_new_symbol(byte *c)
   if (l > SYM_MAX_LEN)
     cf_error("Symbol too long");
 
-  s = cfg_alloc(sizeof(struct symbol) + l);
-  s->scope = conf_this_scope;
-  s->class = SYM_VOID;
-  s->def = NULL;
-  s->aux = 0;
+  s = cfg_allocz(sizeof(struct symbol) + l + 1);
+  *s = (struct symbol) { .scope = conf_this_scope, .class = SYM_VOID, };
   strcpy(s->name, c);
 
   if (!new_config->sym_hash.data)
@@ -574,6 +571,7 @@ cf_find_symbol(struct config *cfg, byte *c)
       (s = HASH_FIND(cfg->sym_hash, SYM, c, 1)))
     return s;
 
+  /* In CLI command parsing, fallback points to the current config, otherwise it is NULL. */
   if (cfg->fallback &&
       cfg->fallback->sym_hash.data &&
       (s = HASH_FIND(cfg->fallback->sym_hash, SYM, c, 1)))
@@ -597,6 +595,28 @@ cf_get_symbol(byte *c)
   return cf_find_symbol(new_config, c) ?: cf_new_symbol(c);
 }
 
+/**
+ * cf_localize_symbol - get the local instance of given symbol
+ * @sym: the symbol to localize
+ *
+ * This functions finds the symbol that is local to current scope
+ * for purposes of cf_define_symbol().
+ */
+struct symbol *
+cf_localize_symbol(struct symbol *sym)
+{
+  /* If the symbol type is void, it has been recently allocated just in this scope. */
+  if (!sym->class)
+    return sym;
+  
+  /* If the scope is the current, it is already defined in this scope. */
+  if (sym->scope == conf_this_scope)
+    cf_error("Symbol already defined");
+
+  /* Not allocated here yet, doing it now. */
+  return cf_new_symbol(sym->name);
+}
+
 struct symbol *
 cf_default_name(char *template, int *counter)
 {
@@ -616,35 +636,6 @@ cf_default_name(char *template, int *counter)
   cf_error("Unable to generate default name");
 }
 
-/**
- * cf_define_symbol - define meaning of a symbol
- * @sym: symbol to be defined
- * @type: symbol class to assign
- * @def: class dependent data
- *
- * Defines new meaning of a symbol. If the symbol is an undefined
- * one (%SYM_VOID), it's just re-defined to the new type. If it's defined
- * in different scope, a new symbol in current scope is created and the
- * meaning is assigned to it. If it's already defined in the current scope,
- * an error is reported via cf_error().
- *
- * Result: Pointer to the newly defined symbol. If we are in the top-level
- * scope, it's the same @sym as passed to the function.
- */
-struct symbol *
-cf_define_symbol(struct symbol *sym, int type, void *def)
-{
-  if (sym->class)
-    {
-      if (sym->scope == conf_this_scope)
-	cf_error("Symbol already defined");
-      sym = cf_new_symbol(sym->name);
-    }
-  sym->class = type;
-  sym->def = def;
-  return sym;
-}
-
 static void
 cf_lex_init_kh(void)
 {
diff --git a/conf/conf.h b/conf/conf.h
index 4e3addb3..21d4f1e2 100644
--- a/conf/conf.h
+++ b/conf/conf.h
@@ -105,11 +105,19 @@ extern int (*cf_read_hook)(byte *buf, uint max, int fd);
 struct symbol {
   struct symbol *next;
   struct sym_scope *scope;
-  int class;
-  int aux;
-  uint aux2;
-  void *def;
-  char name[1];
+  int class;				/* SYM_* */
+  uint flags;				/* SYM_FLAG_* */
+
+  union {
+    struct proto_config *proto;		/* For SYM_PROTO and SYM_TEMPLATE */
+    const struct f_line *function;	/* For SYM_FUNCTION */
+    const struct filter *filter;	/* For SYM_FILTER */
+    struct rtable_config *table;	/* For SYM_TABLE */
+    struct f_dynamic_attr *attribute;	/* For SYM_ATTRIBUTE */
+    struct f_val *val;			/* For SYM_CONSTANT or SYM_VARIABLE */
+  };
+
+  char name[0];
 };
 
 struct sym_scope {
@@ -134,8 +142,11 @@ struct sym_scope {
 #define SYM_CONSTANT 0x200	/* 0x200-0x2ff are variable types */
 #define SYM_CONSTANT_RANGE SYM_CONSTANT ... (SYM_CONSTANT | 0xff)
 
-#define SYM_TYPE(s) (((struct f_val *) (s)->def)->type)
-#define SYM_VAL(s) (((struct f_val *) (s)->def)->val)
+#define SYM_TYPE(s) ((s)->val->type)
+#define SYM_VAL(s) ((s)->val->val)
+
+/* Symbol flags */
+#define SYM_FLAG_SAME 0x1	/* For SYM_FUNCTION and SYM_FILTER */
 
 struct include_file_stack {
   void *buffer;				/* Internal lexer state */
@@ -160,7 +171,29 @@ struct symbol *cf_find_symbol(struct config *cfg, byte *c);
 
 struct symbol *cf_get_symbol(byte *c);
 struct symbol *cf_default_name(char *template, int *counter);
-struct symbol *cf_define_symbol(struct symbol *symbol, int type, void *def);
+struct symbol *cf_localize_symbol(struct symbol *sym);
+
+/**
+ * cf_define_symbol - define meaning of a symbol
+ * @sym: symbol to be defined
+ * @type: symbol class to assign
+ * @def: class dependent data
+ *
+ * Defines new meaning of a symbol. If the symbol is an undefined
+ * one (%SYM_VOID), it's just re-defined to the new type. If it's defined
+ * in different scope, a new symbol in current scope is created and the
+ * meaning is assigned to it. If it's already defined in the current scope,
+ * an error is reported via cf_error().
+ *
+ * Result: Pointer to the newly defined symbol. If we are in the top-level
+ * scope, it's the same @sym as passed to the function.
+ */
+#define cf_define_symbol(sym_, type_, var_, def_) ({ \
+    struct symbol *sym = cf_localize_symbol(sym_); \
+    sym->class = type_; \
+    sym->var_ = def_; \
+    sym; })
+
 void cf_push_scope(struct symbol *);
 void cf_pop_scope(void);
 char *cf_symbol_class_name(struct symbol *sym);
diff --git a/conf/confbase.Y b/conf/confbase.Y
index 2195e8fc..62415b4c 100644
--- a/conf/confbase.Y
+++ b/conf/confbase.Y
@@ -56,7 +56,8 @@ CF_DECLS
   struct f_dynamic_attr fda;
   struct f_static_attr fsa;
   struct f_lval flv;
-  struct filter *f;
+  const struct f_line *fl;
+  const struct filter *f;
   struct f_tree *e;
   struct f_trie *trie;
   struct f_val v;
@@ -130,7 +131,7 @@ definition:
    DEFINE CF_SYM_VOID '=' term ';' {
      struct f_val *val = cfg_alloc(sizeof(struct f_val));
      if (f_eval(f_postfixify($4), cfg_mem, val) > F_RETURN) cf_error("Runtime error");
-     cf_define_symbol($2, SYM_CONSTANT | val->type, val);
+     cf_define_symbol($2, SYM_CONSTANT | val->type, val, val);
    }
  ;