From: K.Kosako <kosako@sofnec.co.jp>
Date: Mon, 26 Aug 2019 00:48:38 +0000 (+0900)
Subject: add backref_num member into ScanEnv
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=c3317af63597d9076bd42123948bdea66f3ed22a;p=onig

add backref_num member into ScanEnv
---

diff --git a/src/regcomp.c b/src/regcomp.c
index 6b64fb9..ec714a1 100644
--- a/src/regcomp.c
+++ b/src/regcomp.c
@@ -6585,11 +6585,12 @@ onig_compile(regex_t* reg, const UChar* pattern, const UChar* pattern_end,
   r = setup_tree(root, reg, 0, &scan_env);
   if (r != 0) goto err_unset;
 
-  set_parent_node_trav(root, NULL_NODE);
-  r = set_empty_repeat_node_trav(root, NULL_NODE, &scan_env);
-  if (r != 0) goto err_unset;
-  set_empty_status_check_trav(root, &scan_env);
-
+  if (scan_env.backref_num != 0) {
+    set_parent_node_trav(root, NULL_NODE);
+    r = set_empty_repeat_node_trav(root, NULL_NODE, &scan_env);
+    if (r != 0) goto err_unset;
+    set_empty_status_check_trav(root, &scan_env);
+  }
 
 #ifdef ONIG_DEBUG_PARSE
   print_tree(stderr, root);
diff --git a/src/regparse.c b/src/regparse.c
index 0dd48e8..5d667cd 100644
--- a/src/regparse.c
+++ b/src/regparse.c
@@ -1966,6 +1966,7 @@ scan_env_clear(ScanEnv* env)
   xmemset(env->mem_env_static, 0, sizeof(env->mem_env_static));
 
   env->parse_depth         = 0;
+  env->backref_num         = 0;
   env->keep_num            = 0;
   env->save_num            = 0;
   env->save_alloc_num      = 0;
@@ -2347,6 +2348,8 @@ node_new_backref(int back_num, int* backrefs, int by_name,
     for (i = 0; i < back_num; i++)
       p[i] = backrefs[i];
   }
+
+  env->backref_num++;
   return node;
 }
 
diff --git a/src/regparse.h b/src/regparse.h
index efae60f..0ee42d4 100644
--- a/src/regparse.h
+++ b/src/regparse.h
@@ -418,7 +418,7 @@ typedef struct {
   MemEnv           mem_env_static[SCANENV_MEMENV_SIZE];
   MemEnv*          mem_env_dynamic;
   unsigned int     parse_depth;
-
+  int backref_num;
   int keep_num;
   int save_num;
   int save_alloc_num;