Issue #5386: mmap.write_byte didn't check map size, so it could cause buffer
overrun.
diff --git a/Lib/test/test_mmap.py b/Lib/test/test_mmap.py
index c06b757..c8e52a6 100644
--- a/Lib/test/test_mmap.py
+++ b/Lib/test/test_mmap.py
@@ -467,6 +467,38 @@
self.assert_(issubclass(mmap.error, EnvironmentError))
self.assert_("mmap.error" in str(mmap.error))
+ def test_io_methods(self):
+ data = "0123456789"
+ open(TESTFN, "wb").write("x"*len(data))
+ f = open(TESTFN, "r+b")
+ m = mmap.mmap(f.fileno(), len(data))
+ f.close()
+ # Test write_byte()
+ for i in xrange(len(data)):
+ self.assertEquals(m.tell(), i)
+ m.write_byte(data[i:i+1])
+ self.assertEquals(m.tell(), i+1)
+ self.assertRaises(ValueError, m.write_byte, "x")
+ self.assertEquals(m[:], data)
+ # Test read_byte()
+ m.seek(0)
+ for i in xrange(len(data)):
+ self.assertEquals(m.tell(), i)
+ self.assertEquals(m.read_byte(), data[i:i+1])
+ self.assertEquals(m.tell(), i+1)
+ self.assertRaises(ValueError, m.read_byte)
+ # Test read()
+ m.seek(3)
+ self.assertEquals(m.read(3), "345")
+ self.assertEquals(m.tell(), 6)
+ # Test write()
+ m.seek(3)
+ m.write("bar")
+ self.assertEquals(m.tell(), 6)
+ self.assertEquals(m[:], "012bar6789")
+ m.seek(8)
+ self.assertRaises(ValueError, m.write, "bar")
+
def test_main():
run_unittest(MmapTests)