BitstreamLE: Test invalid reads preserve previous offset

.github/workflows/ZenLib_Checks.yml

@@ -55,8 +55,9 @@ jobs:
             echo "::endgroup::"
             if [ -z "${{ matrix.no_cmake }}" ] ; then
               echo "::group::CMake, Unicode ${Unicode}"
-              cmake -S Project/CMake -B build_${Unicode} -DCMAKE_BUILD_TYPE=Release -DENABLE_UNICODE=$([ "${Unicode}" == "yes" ] && echo ON || echo OFF)
+              cmake -S Project/CMake -B build_${Unicode} -DCMAKE_BUILD_TYPE=Release -DBUILD_ZENLIB_TESTS=ON -DENABLE_UNICODE=$([ "${Unicode}" == "yes" ] && echo ON || echo OFF)
               cmake --build build_${Unicode} -j4
+              ctest --test-dir build_${Unicode} --output-on-failure
               echo "::endgroup::"
             fi
           done
@@ -213,10 +214,12 @@ jobs:
         run: |
           foreach ($Unicode in 'ON', 'OFF') {
             Write-Host "::group::Unicode $Unicode"
-            cmake -S Project/CMake -B build_$Unicode -DCMAKE_BUILD_TYPE=Release -DENABLE_UNICODE=$Unicode
+            cmake -S Project/CMake -B build_$Unicode -DCMAKE_BUILD_TYPE=Release -DBUILD_ZENLIB_TESTS=ON -DENABLE_UNICODE=$Unicode
             if ($LASTEXITCODE) { exit 1 }
             cmake --build build_$Unicode --config Release
             if ($LASTEXITCODE) { exit 1 }
+            ctest --test-dir build_$Unicode -C Release --output-on-failure
+            if ($LASTEXITCODE) { exit 1 }
             Write-Host "::endgroup::"
           }
 

Project/CMake/CMakeLists.txt

@@ -15,6 +15,7 @@ endif()
 
 option(ENABLE_UNICODE "Enable unicode support" ON)
 option(LARGE_FILES "Enable large files support" ON)
+option(BUILD_ZENLIB_TESTS "Build ZenLib tests" OFF)
 
 set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} "${CMAKE_CURRENT_SOURCE_DIR}/Modules/")
 set(ZenLib_SOURCES_PATH ${CMAKE_CURRENT_SOURCE_DIR}/../../Source)
@@ -186,6 +187,15 @@ set_target_properties(zen PROPERTIES
 include(EnableLatestCXX)
 enable_latest_cxx(zen)
 
+if(BUILD_ZENLIB_TESTS)
+  enable_testing()
+  add_executable(zen_bitstream_tests
+    ${CMAKE_CURRENT_SOURCE_DIR}/../GNU/Library/Tests/BitStream.cpp)
+  target_link_libraries(zen_bitstream_tests PRIVATE zen)
+  enable_latest_cxx(zen_bitstream_tests)
+  add_test(NAME ZenLib.BitStream COMMAND zen_bitstream_tests)
+endif()
+
 install(TARGETS zen EXPORT zen-export
   PUBLIC_HEADER DESTINATION ${INCLUDE_INSTALL_DIR}/ZenLib
   RUNTIME DESTINATION ${BIN_INSTALL_DIR}

Project/GNU/Library/Makefile.am

@@ -80,12 +80,20 @@ pkgconfig_DATA = libzen.pc
 
 AM_TESTS_FD_REDIRECT = 9>&2
 
-TESTS = test/filename.sh
+TESTS = \
+ test/filename.sh \
+ Tests/zen_bitstream
 
-check_PROGRAMS = test/zen_filename
+check_PROGRAMS = \
+ test/zen_filename \
+ Tests/zen_bitstream
 test_zen_filename_SOURCES = test/Source/filename.cpp
 test_zen_filename_CXXFLAGS = $(AM_CXXFLAGS) -Wall -Wextra
 test_zen_filename_LDADD = libzen.la
 
+Tests_zen_bitstream_SOURCES = Tests/BitStream.cpp
+Tests_zen_bitstream_CXXFLAGS = $(AM_CXXFLAGS) -Wall -Wextra
+Tests_zen_bitstream_LDADD = libzen.la
+
 AM_CXXFLAGS = -std=c++11
 AM_CPPFLAGS = -I../../../Source

Project/GNU/Library/Tests/BitStream.cpp

@@ -0,0 +1,68 @@
+/*  Copyright (c) MediaArea.net SARL. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a zlib-style license that can
+ *  be found in the License.txt file in the root of the source tree.
+ */
+
+#include "ZenLib/BitStream_LE.h"
+
+#include <iostream>
+
+using namespace ZenLib;
+
+namespace
+{
+
+bool Check(bool Condition, const char* Message)
+{
+    if (Condition)
+        return true;
+
+    std::cerr << Message << '\n';
+    return false;
+}
+
+bool InvalidReadDoesNotChangePreviousOffset()
+{
+    const int8u Data[] = { 0x11, 0x22, 0x33 };
+    BitStream_LE BitStream(Data, sizeof(Data));
+
+    if (!Check(BitStream.Get(8)==0x11, "Initial read returned an unexpected value"))
+        return false;
+    if (!Check(BitStream.OffsetBeforeLastCall_Get()==0, "Initial read stored an unexpected previous offset"))
+        return false;
+
+    const auto Remain=BitStream.Remain();
+    const auto Offset=BitStream.Offset_Get();
+    const auto BitOffset=BitStream.BitOffset_Get();
+    const auto PreviousOffset=BitStream.OffsetBeforeLastCall_Get();
+
+    if (!Check(BitStream.Get(0)==0, "A zero-bit read returned an unexpected value"))
+        return false;
+    if (!Check(BitStream.Get(33)==0, "An oversized read returned an unexpected value"))
+        return false;
+    BitStream.Skip(0);
+
+    if (!Check(BitStream.Remain()==Remain, "An invalid read changed the remaining bit count"))
+        return false;
+    if (!Check(BitStream.Offset_Get()==Offset, "An invalid read changed the byte offset"))
+        return false;
+    if (!Check(BitStream.BitOffset_Get()==BitOffset, "An invalid read changed the bit offset"))
+        return false;
+    if (!Check(BitStream.OffsetBeforeLastCall_Get()==PreviousOffset, "An invalid read changed the previous-call offset"))
+        return false;
+
+    if (!Check(BitStream.Get(8)==0x22, "Second valid read returned an unexpected value"))
+        return false;
+    if (!Check(BitStream.OffsetBeforeLastCall_Get()==1, "A valid read did not update the previous-call offset"))
+        return false;
+
+    return true;
+}
+
+} // unnamed namespace
+
+int main()
+{
+    return InvalidReadDoesNotChangePreviousOffset() ? 0 : 1;
+}