add call stacks to errors

3 files changed, 179 insertions, 6 deletions

diff --git a/cxx/include/aesnixx/all.hpp b/cxx/include/aesnixx/all.hpp
index 72ea262..1452f68 100644
--- a/cxx/include/aesnixx/all.hpp
+++ b/cxx/include/aesnixx/all.hpp
@@ -10,4 +10,5 @@
 
 #include "aes.hpp"
 #include "data.hpp"
+#include "debug.hpp"
 #include "error.hpp"
diff --git a/cxx/include/aesnixx/debug.hpp b/cxx/include/aesnixx/debug.hpp
new file mode 100644
index 0000000..f87942d
--- /dev/null
+++ b/cxx/include/aesnixx/debug.hpp
@@ -0,0 +1,123 @@
+/**
+ * \file
+ * \author Egor Tensin <Egor.Tensin@gmail.com>
+ * \date 2015
+ * \copyright This file is licensed under the terms of the MIT License.
+ *            See LICENSE.txt for details.
+ */
+
+#pragma once
+
+#ifdef WIN32
+#include <Windows.h>
+#include <DbgHelp.h>
+#pragma comment(lib, "dbghelp.lib")
+#endif
+
+#include <cstddef>
+
+#include <sstream>
+#include <string>
+
+namespace aesni
+{
+    namespace aux
+    {
+        class CallStackFormatter
+        {
+        public:
+            CallStackFormatter()
+            {
+                #ifdef WIN32
+                m_valid = SymInitialize(GetCurrentProcess(), NULL, TRUE) ? true : false;
+                #endif
+            }
+
+            std::string format(void* addr) const
+            {
+                #ifdef WIN32
+                if (!m_valid)
+                    return format_fallback(addr);
+
+                DWORD64 symbol_info_buf[sizeof(SYMBOL_INFO) + MAX_SYM_NAME];
+                PSYMBOL_INFO symbol_info = (PSYMBOL_INFO) symbol_info_buf;
+                symbol_info->SizeOfStruct = sizeof(SYMBOL_INFO);
+                symbol_info->MaxNameLen = MAX_SYM_NAME;
+
+                IMAGEHLP_MODULE64 module_info;
+                module_info.SizeOfStruct = sizeof(IMAGEHLP_MODULE64);
+
+                DWORD64 displacement_within_symbol;
+
+                if (!SymFromAddr(GetCurrentProcess(), reinterpret_cast<DWORD64>(addr), &displacement_within_symbol, symbol_info))
+                {
+                    if (!SymGetModuleInfo64(GetCurrentProcess(), reinterpret_cast<DWORD64>(addr), &module_info))
+                        return format_fallback(addr);
+
+                    void* const displacement_within_module = reinterpret_cast<char*>(addr) - module_info.BaseOfImage;
+                    return format_with_module(module_info.ModuleName, displacement_within_module);
+                }
+
+                if (!SymGetModuleInfo64(GetCurrentProcess(), symbol_info->ModBase, &module_info))
+                    return format_with_symbol(symbol_info->Name, addr);
+
+                return format_with_symbol_and_module(symbol_info->Name, module_info.ModuleName, reinterpret_cast<void*>(displacement_within_symbol));
+                #else
+                return format_fallback(addr);
+                #endif
+            }
+
+            ~CallStackFormatter()
+            {
+                #ifdef WIN32
+                if (m_valid)
+                    SymCleanup(GetCurrentProcess());
+                #endif
+            }
+
+        private:
+            template <typename T>
+            static std::string put_between_brackets(const T& x)
+            {
+                std::ostringstream oss;
+                oss << "[" << x << "]";
+                return oss.str();
+            }
+
+            template <typename T>
+            static std::string stringify(const T& x)
+            {
+                std::ostringstream oss;
+                oss << x;
+                return oss.str();
+            }
+
+            std::string format_fallback(void* addr) const
+            {
+                return put_between_brackets(addr);
+            }
+
+            std::string format_with_module(const std::string& module_name, void* displacement) const
+            {
+                if (displacement == NULL)
+                    return put_between_brackets(module_name);
+                else
+                    return put_between_brackets(module_name + "+" + stringify(displacement));
+            }
+
+            std::string format_with_symbol(const std::string& symbol_name, void* displacement) const
+            {
+                return format_with_module(symbol_name, displacement);
+            }
+
+            std::string format_with_symbol_and_module(const std::string& symbol_name, const std::string& module_name, void* displacement) const
+            {
+                return format_with_symbol(module_name + "!" + symbol_name, displacement);
+            }
+
+            #ifdef WIN32
+            bool m_valid = false;
+            #endif
+        };
+    }
+}
diff --git a/cxx/include/aesnixx/error.hpp b/cxx/include/aesnixx/error.hpp
index 4c1fc98..013e2ef 100644
--- a/cxx/include/aesnixx/error.hpp
+++ b/cxx/include/aesnixx/error.hpp
@@ -8,16 +8,70 @@
 
 #pragma once
 
+#include "debug.hpp"
+
 #include <aesni/all.h>
 
 #include <cstdlib>
+#include <cstring>
 
+#include <algorithm>
+#include <functional>
+#include <ostream>
 #include <stdexcept>
 #include <string>
 #include <vector>
 
 namespace aesni
 {
+    class Error : public std::runtime_error
+    {
+    public:
+        Error(const AesNI_ErrorDetails& err_details)
+            : std::runtime_error(format_error_message(err_details))
+        {
+            copy_call_stack(err_details);
+        }
+
+        void for_each_in_call_stack(const std::function<void (void*, const std::string&)>& callback) const
+        {
+            aux::CallStackFormatter formatter;
+            std::for_each(m_call_stack, m_call_stack + m_call_stack_size, [&formatter, &callback] (void* addr)
+            {
+                callback(addr, formatter.format(addr));
+            });
+        }
+
+    private:
+        static std::string format_error_message(const AesNI_ErrorDetails& err_details)
+        {
+            std::vector<char> buf;
+            buf.resize(aesni_format_error(&err_details, NULL, 0));
+            aesni_format_error(&err_details, buf.data(), buf.size());
+            return { buf.begin(), buf.end() };
+        }
+
+        void copy_call_stack(const AesNI_ErrorDetails& err_details)
+        {
+            m_call_stack_size = err_details.call_stack_size;
+            std::memcpy(m_call_stack, err_details.call_stack, m_call_stack_size * sizeof(void*));
+        }
+
+        void* m_call_stack[AESNI_MAX_CALL_STACK_LENGTH];
+        std::size_t m_call_stack_size;
+    };
+
+    std::ostream& operator<<(std::ostream& os, const Error& e)
+    {
+        os << "AesNI error: " << e.what() << '\n';
+        os << "Call stack:\n";
+        e.for_each_in_call_stack([&os] (void* addr, const std::string& name)
+        {
+            os << '\t' << addr << ' ' << name << '\n';
+        });
+        return os;
+    }
+
     class ErrorDetailsThrowsInDestructor
     {
     public:
@@ -29,12 +83,7 @@ namespace aesni
         ~ErrorDetailsThrowsInDestructor()
         {
             if (aesni_is_error(aesni_get_error_code(get())))
-            {
-                std::vector<char> msg;
-                msg.resize(aesni_format_error(get(), NULL, 0));
-                aesni_format_error(get(), msg.data(), msg.size());
-                throw std::runtime_error(std::string(msg.begin(), msg.end()));
-            }
+                throw Error(m_impl);
         }
 
         AesNI_ErrorDetails* get() { return &m_impl; }