From a1101296aa6f1c0ed42f4a49ec1da63b7f76a78f Mon Sep 17 00:00:00 2001
From: Yuichi Nishiwaki <yuichi.nishiwaki@gmail.com>
Date: Wed, 26 Mar 2014 14:49:48 +0900
Subject: [PATCH] refactor pic_gensym

---
 src/symbol.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/src/symbol.c b/src/symbol.c
index 4501e3af..aa57d655 100644
--- a/src/symbol.c
+++ b/src/symbol.c
@@ -40,13 +40,13 @@ pic_intern_cstr(pic_state *pic, const char *str)
 pic_sym
 pic_gensym(pic_state *pic, pic_sym base)
 {
-  int id;
+  int uid = pic->uniq_sym_cnt++, len;
   char *str;
   pic_sym uniq;
 
-  id = ++pic->uniq_sym_cnt;
-  str = (char *)pic_alloc(pic, strlen(pic_symbol_name(pic, base)) + (int)log10(id) + 3);
-  sprintf(str, "%s@%d", pic_symbol_name(pic, base), id);
+  len = snprintf(NULL, 0, "%s@%d", pic_symbol_name(pic, base), uid);
+  str = pic_alloc(pic, len + 1);
+  sprintf(str, "%s@%d", pic_symbol_name(pic, base), uid);
 
   /* don't put the symbol to pic->syms to keep it uninterned */
   uniq = pic->sym_cnt++;