commit e245b055a83c2b3c45b8f29828cec0594844a15c
author Davide Pesavento <davide.pesavento@lip6.fr> Tue Oct 31 13:00:44 2017 -0400
committer Davide Pesavento <davide.pesavento@lip6.fr> Sat Nov 04 00:56:57 2017 -0400
tree 136b0e38bdf4468bdeac76fcaf6802ef1268015d
parent 9ced9e690be6809d66acd9529acdf6d1b4af0504

encoding: don't call memcmp() with null pointer

It's undefined behavior.

Change-Id: Id2fd5cbc0483af2bf9857e81fb6cac8163da3474
Refs: #4368

src/encoding/block.cpp

diff --git a/src/encoding/block.cpp b/src/encoding/block.cpp
index 13b10bc..691bbdf 100644
--- a/src/encoding/block.cpp
+++ b/src/encoding/block.cpp
@@ -28,6 +28,7 @@
 
 #include <boost/asio/buffer.hpp>
 #include <boost/range/adaptor/reversed.hpp>
+#include <cstring>
 
 namespace ndn {
 
@@ -504,7 +505,8 @@
 {
   return lhs.type() == rhs.type() &&
          lhs.value_size() == rhs.value_size() &&
-         ::memcmp(lhs.value(), rhs.value(), lhs.value_size()) == 0;
+         (lhs.value_size() == 0 ||
+          std::memcmp(lhs.value(), rhs.value(), lhs.value_size()) == 0);
 }
 
 } // namespace ndn

src/name-component.cpp

diff --git a/src/name-component.cpp b/src/name-component.cpp
index 5cf31aa..36a01f9 100644
--- a/src/name-component.cpp
+++ b/src/name-component.cpp
@@ -31,6 +31,7 @@
 #include "util/string-helper.hpp"
 
 #include <boost/algorithm/string/trim.hpp>
+#include <cstring>
 #include <sstream>
 
 namespace ndn {
@@ -387,7 +388,7 @@
 {
   return type() == other.type() &&
          value_size() == other.value_size() &&
-         (empty() || // needed on OSX 10.9 due to STL bug
+         (empty() || // needed with Apple clang < 9.0.0 due to libc++ bug
           std::equal(value_begin(), value_end(), other.value_begin()));
 }
 
@@ -410,7 +411,7 @@
   if (cmpSize != 0)
     return cmpSize;
 
-  if (empty()) // needed on OSX 10.9 due to STL bug
+  if (empty())
     return 0;
 
   return std::memcmp(value(), other.value(), value_size());

tests/unit-tests/name-component.t.cpp

diff --git a/tests/unit-tests/name-component.t.cpp b/tests/unit-tests/name-component.t.cpp
index 651b160..d91ce24 100644
--- a/tests/unit-tests/name-component.t.cpp
+++ b/tests/unit-tests/name-component.t.cpp
@@ -91,11 +91,19 @@
 
 BOOST_AUTO_TEST_CASE(Generic)
 {
+  name::Component empty;
   name::Component compD("D");
   name::Component compD2("D");
   name::Component compF("F");
   name::Component compAA("AA");
 
+  BOOST_CHECK_EQUAL(empty == empty, true);
+  BOOST_CHECK_EQUAL(empty != empty, false);
+  BOOST_CHECK_EQUAL(empty < empty, false);
+  BOOST_CHECK_EQUAL(empty <= empty, true);
+  BOOST_CHECK_EQUAL(empty == compD, false);
+  BOOST_CHECK_EQUAL(empty < compD, true);
+
   BOOST_CHECK_EQUAL(compD == compD2, true);
   BOOST_CHECK_EQUAL(compD != compD2, false);
   BOOST_CHECK_EQUAL(compD < compD2, false);