Merge #3107 #3155

3107: Log close error to console r=Jupeyy a=def-



3155: Add memcheck/asan/ubsan to readme r=Jupeyy a=def-

To be linked from https://github.com/ddnet/ddnet/pull/3133

Co-authored-by: def <dennis@felsin9.de>

README.md

@@ -111,6 +111,25 @@ sudo cp *.a /usr/lib
 To run the tests you must target `run_tests` with make:
 `make run_tests`
 
+Using AddressSanitizer + UndefinedBehaviourSanitizer or Valgrind's Memcheck
+---------------------------------------------------------------------------
+ASan+UBSan and Memcheck are useful to find code problems more easily. Please use them to test your changes if you can.
+
+For ASan+UBSan compile with:
+```bash
+CC=clang CXX=clang++ CXXFLAGS="-fsanitize=address,undefined -fsanitize-recover=address,undefined -fno-omit-frame-pointer" CFLAGS="-fsanitize=address,undefined -fsanitize-recover=address,undefined -fno-omit-frame-pointer" cmake -DCMAKE_BUILD_TYPE=Debug .
+make
+```
+and run with:
+```bash
+UBSAN_OPTIONS=log_path=./SAN:print_stacktrace=1:halt_on_errors=0 ASAN_OPTIONS=log_path=./SAN:print_stacktrace=1:check_initialization_order=1:detect_leaks=1:halt_on_errors=0 ./DDNet
+```
+
+Check the SAN.\* files afterwards. This finds more problems than memcheck, runs faster, but requires a modern GCC/Clang compiler.
+
+For valgrind's memcheck compile a normal Debug build and run with: `valgrind --tool=memcheck ./DDNet`
+Expect a large slow down.
+
 Building on Windows with Visual Studio
 --------------------------------------
 

src/engine/client/http.cpp

@@ -287,6 +287,7 @@ int CGetFile::OnCompletion(int State)
 {
 	if(m_File && io_close(m_File) != 0)
 	{
+		dbg_msg("http", "i/o error, cannot close file: %s", m_aDest);
 		State = HTTP_ERROR;
 	}