From db3ddad3a710de4f0c6ef5d47493c5f7ba9b7384 Mon Sep 17 00:00:00 2001
From: nobu <nobu@b2dd03c8-39d4-4d8f-98ff-823fe69b080e>
Date: Thu, 11 Jul 2013 11:17:54 +0000
Subject: [PATCH] string.c: check null char

* string.c (rb_string_value_cstr): check null char in char, not in
  byte.


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@41918 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
---
 ChangeLog                      |  5 +++++
 string.c                       | 20 ++++++++++++++++++++
 test/-ext-/string/test_cstr.rb | 19 +++++++++++++++++++
 3 files changed, 44 insertions(+)

diff --git a/ChangeLog b/ChangeLog
index f093150913..ee399d68d6 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Thu Jul 11 20:17:51 2013  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* string.c (rb_string_value_cstr): check null char in char, not in
+	  byte.
+
 Thu Jul 11 14:48:35 2013  Zachary Scott  <e@zzak.io>
 
 	* array.c: Replace confusing example for #reverse_each in overview
diff --git a/string.c b/string.c
index 9824ccb520..ec870eb6b9 100644
--- a/string.c
+++ b/string.c
@@ -1459,13 +1459,33 @@ rb_string_value_ptr(volatile VALUE *ptr)
     return RSTRING_PTR(str);
 }
 
+static const char *
+str_null_char(const char *s, long len, rb_encoding *enc)
+{
+    int n;
+    const char *e = s + len;
+
+    for (; s < e; s += n) {
+	if (!rb_enc_codepoint_len(s, e, &n, enc)) return s;
+    }
+    return 0;
+}
+
 char *
 rb_string_value_cstr(volatile VALUE *ptr)
 {
     VALUE str = rb_string_value(ptr);
     char *s = RSTRING_PTR(str);
     long len = RSTRING_LEN(str);
+    rb_encoding *enc = rb_enc_get(str);
+    const int minlen = rb_enc_mbminlen(enc);
 
+    if (minlen > 1) {
+	if (str_null_char(s, len, enc)) {
+	    rb_raise(rb_eArgError, "string contains null char");
+	}
+    }
+    else
     if (!s || memchr(s, 0, len)) {
 	rb_raise(rb_eArgError, "string contains null byte");
     }
diff --git a/test/-ext-/string/test_cstr.rb b/test/-ext-/string/test_cstr.rb
index 8c0bb136ad..8ea86aa6da 100644
--- a/test/-ext-/string/test_cstr.rb
+++ b/test/-ext-/string/test_cstr.rb
@@ -14,4 +14,23 @@ class Test_StringCStr < Test::Unit::TestCase
     s = Bug::String.new("abcdef")*100000
     assert_equal(0, s.cstr_term, Bug4319)
   end
+
+  WCHARS = [Encoding::UTF_16BE, Encoding::UTF_16LE, Encoding::UTF_32BE, Encoding::UTF_32LE]
+
+  def test_wchar_embed
+    WCHARS.each do |enc|
+      s = Bug::String.new("ab".encode(enc))
+      assert_nothing_raised(ArgumentError) {s.cstr_term}
+    end
+  end
+
+  def test_wchar_long
+    str = "abcdef"
+    n = 100
+    len = str.size * n
+    WCHARS.each do |enc|
+      s = Bug::String.new(str.encode(enc))*n
+      assert_nothing_raised(ArgumentError) {s.cstr_term}
+    end
+  end
 end