Add winapi demangling

CMakeLists.txt

@@ -37,6 +37,7 @@ option(CPPTRACE_UNWIND_WITH_WINAPI "" OFF)
 option(CPPTRACE_UNWIND_WITH_NOTHING "" OFF)
 
 option(CPPTRACE_DEMANGLE_WITH_CXXABI "" OFF)
+option(CPPTRACE_DEMANGLE_WITH_WINAPI "" OFF)
 option(CPPTRACE_DEMANGLE_WITH_NOTHING "" OFF)
 
 set(CPPTRACE_BACKTRACE_PATH "" CACHE STRING "Path to backtrace.h, if the compiler doesn't already know it. Check /usr/lib/gcc/x86_64-linux-gnu/*/include.")
@@ -187,12 +188,16 @@ endif()
 if(
   NOT (
     CPPTRACE_DEMANGLE_WITH_CXXABI OR
+    CPPTRACE_DEMANGLE_WITH_WINAPI OR
     CPPTRACE_DEMANGLE_WITH_NOTHING
   )
 )
   if(HAS_CXXABI)
-    message(STATUS "Cpptrace auto config: Using cxxabi for symbols")
+    message(STATUS "Cpptrace auto config: Using cxxabi for demangling")
     set(CPPTRACE_DEMANGLE_WITH_CXXABI On)
+  elseif(WIN32 AND NOT MINGW)
+    message(STATUS "Cpptrace auto config: Using dbghelp for demangling")
+    set(CPPTRACE_DEMANGLE_WITH_WINAPI On)
   else()
     set(CPPTRACE_DEMANGLE_WITH_NOTHING On)
   endif()
@@ -210,6 +215,7 @@ set(
   sources
   src/cpptrace.cpp
   src/demangle/demangle_with_cxxabi.cpp
+  src/demangle/demangle_with_winapi.cpp
   src/demangle/demangle_with_nothing.cpp
   src/symbols/symbols_with_addr2line.cpp
   src/symbols/symbols_with_dbghelp.cpp
@@ -361,6 +367,11 @@ if(CPPTRACE_DEMANGLE_WITH_CXXABI)
   target_compile_definitions(cpptrace PUBLIC CPPTRACE_DEMANGLE_WITH_CXXABI)
 endif()
 
+if(CPPTRACE_DEMANGLE_WITH_WINAPI)
+  target_compile_definitions(cpptrace PUBLIC CPPTRACE_DEMANGLE_WITH_WINAPI)
+  target_link_libraries(cpptrace PRIVATE dbghelp)
+endif()
+
 if(CPPTRACE_DEMANGLE_WITH_NOTHING)
   target_compile_definitions(cpptrace PUBLIC CPPTRACE_DEMANGLE_WITH_NOTHING)
 endif()

README.md

@@ -417,8 +417,9 @@ search the system path for `addr2line` at runtime. This is not the default to pr
 Lastly, depending on other back-ends used a demangler back-end may be needed.
 
 | Library   | CMake config                     | Platforms           | Info                                                                               |
-| -------- | -------------------------------- | ------------------- | ---------------------------------------------------------------------------------- |
+| --------- | -------------------------------- | ------------------- | ---------------------------------------------------------------------------------- |
 | cxxabi.h  | `CPPTRACE_DEMANGLE_WITH_CXXABI`  | Linux, macos, mingw | Should be available everywhere other than [msvc](https://godbolt.org/z/93ca9rcdz). |
+| dbghelp.h | `CPPTRACE_DEMANGLE_WITH_WINAPI`  | Windows             | Demangle with `UnDecorateSymbolName`. |
 | N/A       | `CPPTRACE_DEMANGLE_WITH_NOTHING` | all                 | Don't attempt to do anything beyond what the symbol resolution back-end does.      |
 
 **More?**
@@ -442,6 +443,7 @@ Back-ends:
 - `CPPTRACE_UNWIND_WITH_WINAPI=On/Off`
 - `CPPTRACE_UNWIND_WITH_NOTHING=On/Off`
 - `CPPTRACE_DEMANGLE_WITH_CXXABI=On/Off`
+- `CPPTRACE_DEMANGLE_WITH_WINAPI=On/Off`
 - `CPPTRACE_DEMANGLE_WITH_NOTHING=On/Off`
 
 Back-end configuration:

src/demangle/demangle_with_winapi.cpp

@@ -0,0 +1,26 @@
+#ifdef CPPTRACE_DEMANGLE_WITH_WINAPI
+
+#include "demangle.hpp"
+
+#include <cstdlib>
+#include <string>
+
+#include <windows.h>
+#include <dbghelp.h>
+
+namespace cpptrace {
+namespace detail {
+    std::string demangle(const std::string& name) {
+        char buffer[500];
+        auto ret = UnDecorateSymbolName(name.c_str(), buffer, sizeof(buffer) - 1, 0);
+        if(ret == 0) {
+            return name;
+        } else {
+            buffer[ret] = 0; // just in case, ms' docs unclear if null terminator inserted
+            return buffer;
+        }
+    }
+}
+}
+
+#endif