Allow user setting Userdata for P4_Tokens.

ROADMAP.md

@@ -35,6 +35,7 @@
 - [ ] Except (Any but).
 - [ ] Any.
 - [ ] Until.
+- [x] print token ast in json format. Added in v1.8.0.
 - [x] GetErrorString. Added in v1.7.0.
 - [x] Join. Added in v1.7.0.
 - [x] Start-of-Input & End-of-Input. Added in v1.7.0.

peppapeg.c

@@ -326,6 +326,20 @@ P4_DeleteToken(P4_Token* token) {
     }
 }
 
+P4_PRIVATE(void)
+P4_DeleteTokenUserData(P4_Grammar* grammar, P4_Token* token) {
+    if (grammar->free_func == NULL)
+        return;
+
+    P4_Token* tmp = token;
+    while (tmp != NULL) {
+        if (tmp->userdata != NULL)
+            grammar->free_func(tmp->userdata);
+        P4_DeleteTokenUserData(grammar, tmp->head);
+        tmp = tmp->next;
+    }
+}
+
 /*
  * Push e into s->frame_stack.
  */
@@ -1296,6 +1310,7 @@ P4_PUBLIC P4_Grammar*    P4_CreateGrammar(void) {
     grammar->depth = P4_DEFAULT_RECURSION_LIMIT;
     grammar->on_match = NULL;
     grammar->on_error = NULL;
+    grammar->free_func = NULL;
     return grammar;
 }
 
@@ -1353,6 +1368,16 @@ P4_GetRecursionLimit(P4_Grammar* grammar) {
     return grammar == NULL ? 0 : grammar->depth;
 }
 
+P4_Error
+P4_SetUserDataFreeFunc(P4_Grammar* grammar, P4_UserDataFreeFunc free_func) {
+    if (grammar == NULL)
+        return P4_NullError;
+
+    grammar->free_func = free_func;
+
+    return P4_Ok;
+}
+
 P4_PUBLIC P4_Error
 P4_AddGrammarRule(P4_Grammar* grammar, P4_RuleID id, P4_Expression* expr) {
     size_t          cap   = grammar->cap;
@@ -1411,8 +1436,10 @@ P4_DeleteSource(P4_Source* source) {
     if (source->errmsg)
         free(source->errmsg);
 
-    if (source->root)
+    if (source->root) {
+        P4_DeleteTokenUserData(source->grammar, source->root);
         P4_DeleteToken(source->root);
+    }
 
     free(source);
 }

peppapeg.h

@@ -236,6 +236,17 @@ typedef char*           P4_String;
  * */
 typedef uint64_t        P4_RuleID;
 
+/**
+ * The reference of user data.
+ */
+typedef void*   P4_UserData;
+
+/**
+ * The function to free user data.
+ */
+typedef void    (*P4_UserDataFreeFunc)(P4_UserData);
+
+
 /*
  *
  * ░██████╗████████╗██████╗░██╗░░░██╗░█████╗░████████╗░██████╗
@@ -399,6 +410,9 @@ typedef struct P4_Token {
     /** The id for matched grammar rule. */
     P4_RuleID               rule_id;
 
+    /** The user data. */
+    P4_UserData             userdata;
+
     /** the sibling token. NULL if not exists. */
     struct P4_Token*        next;
     /** the first child of inner tokens. NULL if not exists. */
@@ -437,6 +451,8 @@ typedef struct P4_Grammar{
     P4_MatchCallback        on_match;
     /** The callback after a match for an expression is failed. */
     P4_ErrorCallback        on_error;
+    /** The callback to free user data. */
+    P4_UserDataFreeFunc     free_func;
 } P4_Grammar;
 
 
@@ -1467,6 +1483,14 @@ P4_Error       P4_SetGrammarRuleFlag(P4_Grammar*, P4_RuleID, P4_ExpressionFlag);
  */
 P4_Error       P4_SetRecursionLimit(P4_Grammar*, size_t limit);
 
+/**
+ * @brief       Set free function for the user data.
+ * @param       grammar     The grammar.
+ * @param       free_func   The free function.
+ * @return      The error code.
+ */
+P4_Error       P4_SetUserDataFreeFunc(P4_Grammar* grammar, P4_UserDataFreeFunc free_func);
+
 /**
  * @brief       Get the maximum allowed recursion calls.
  * @param       grammar     The grammar.