* bignum.c (rb_big_aref): check for Bignum index range.

 [ruby-dev:31271]


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@12855 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

4 files changed, 37 insertions, 15 deletions

diff --git a/ChangeLog b/ChangeLog
index 4c08e24911..93532595fa 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Mon Jul 30 11:16:40 2007  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* bignum.c (rb_big_aref): check for Bignum index range.
+	 [ruby-dev:31271]
+
 Sat Jul 28 09:35:41 2007  Yukihiro Matsumoto  <matz@ruby-lang.org>
 
 	* ext/digest/lib/digest.rb (Digest::self.const_missing): avoid
diff --git a/bignum.c b/bignum.c
index a0402d7d2d..f4c2015c96 100644
--- a/bignum.c
+++ b/bignum.c
@@ -2061,29 +2061,39 @@ static VALUE
 rb_big_aref(VALUE x, VALUE y)
 {
     BDIGIT *xds;
-    int shift;
-    long s1, s2;
+    BDIGIT_DBL num;
+    VALUE shift;
+    long i, s1, s2;
 
     if (TYPE(y) == T_BIGNUM) {
-	if (!RBIGNUM(y)->sign || RBIGNUM(x)->sign)
+	if (!RBIGNUM(y)->sign)
 	    return INT2FIX(0);
-	return INT2FIX(1);
+	if (RBIGNUM(bigtrunc(y))->len > SIZEOF_VALUE/SIZEOF_BDIGITS) {
+	  out_of_range:
+	    return RBIGNUM(x)->sign ? INT2FIX(0) : INT2FIX(1);
+	}
+	shift = big2ulong(y, "long", Qfalse);
+    }
+    else {
+	i = NUM2LONG(y);
+	if (i < 0) return INT2FIX(0);
+	shift = (VALUE)i;
     }
-    shift = NUM2INT(y);
-    if (shift < 0) return INT2FIX(0);
     s1 = shift/BITSPERDIG;
     s2 = shift%BITSPERDIG;
 
+    if (s1 >= RBIGNUM(x)->len) goto out_of_range;
     if (!RBIGNUM(x)->sign) {
-	if (s1 >= RBIGNUM(x)->len) return INT2FIX(1);
-	x = rb_big_clone(x);
-	get2comp(x);
+	xds = BDIGITS(x);
+	i = 0; num = 1;
+	while (num += ~xds[i], ++i <= s1) {
+	    num = BIGDN(num);
+	}
     }
     else {
-	if (s1 >= RBIGNUM(x)->len) return INT2FIX(0);
+	num = BDIGITS(x)[s1];
     }
-    xds = BDIGITS(x);
-    if (xds[s1] & (1<<s2))
+    if (num & ((BDIGIT_DBL)1<<s2))
 	return INT2FIX(1);
     return INT2FIX(0);
 }
diff --git a/test/ruby/test_integer.rb b/test/ruby/test_integer.rb
index 2744f3df42..4ffe0c2fce 100644
--- a/test/ruby/test_integer.rb
+++ b/test/ruby/test_integer.rb
@@ -117,6 +117,13 @@ class TestInteger < Test::Unit::TestCase
         end
       }
     }
+
+    # [ruby-dev:31271]
+    # assert_equal(1, (1 << 0x40000000)[0x40000000])
+    # assert_equal(0, (-1 << 0x40000001)[0x40000000])
+    big_zero = 0x40000000.coerce(0)[0]
+    assert_equal(0, (-0x40000002)[big_zero])
+    assert_equal(1, 0x400000001[big_zero])
   end
 
   def test_plus
diff --git a/version.h b/version.h
index ec7ee38f8d..8c57c87729 100644
--- a/version.h
+++ b/version.h
@@ -1,7 +1,7 @@
 #define RUBY_VERSION "1.9.0"
-#define RUBY_RELEASE_DATE "2007-07-28"
+#define RUBY_RELEASE_DATE "2007-07-30"
 #define RUBY_VERSION_CODE 190
-#define RUBY_RELEASE_CODE 20070728
+#define RUBY_RELEASE_CODE 20070730
 #define RUBY_PATCHLEVEL 0
 
 #define RUBY_VERSION_MAJOR 1
@@ -9,7 +9,7 @@
 #define RUBY_VERSION_TEENY 0
 #define RUBY_RELEASE_YEAR 2007
 #define RUBY_RELEASE_MONTH 7
-#define RUBY_RELEASE_DAY 28
+#define RUBY_RELEASE_DAY 30
 
 #ifdef RUBY_EXTERN
 RUBY_EXTERN const char ruby_version[];