Print stack trace on RangeException

libsrc/core/CMakeLists.txt

@@ -2,6 +2,7 @@
 add_library(ngcore SHARED
   archive.cpp
   bitarray.cpp
+  exception.cpp
   localheap.cpp
   logging.cpp
   flags.cpp

libsrc/core/exception.cpp

@@ -0,0 +1,172 @@
+#include "exception.hpp"
+#include "utils.hpp"
+
+#ifdef __GNUC__
+
+#include <execinfo.h>
+#include <string.h>
+#include <errno.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <iostream>
+#include <dlfcn.h>
+#include <array>
+#include <memory>
+#include <cxxabi.h>
+
+namespace ngcore
+{
+  namespace detail
+  {
+    static int exec(std::string cmd, std::string & out) {
+      std::array<char, 128> buffer;
+      FILE *pipe = popen(cmd.c_str(), "r");
+
+      if (!pipe)
+        throw std::runtime_error("popen() failed!");
+
+      out = "";
+      while (fgets(buffer.data(), buffer.size(), pipe) != nullptr)
+        out += buffer.data();
+
+      int error_code = pclose(pipe);
+      return error_code;
+    }
+
+#ifdef __APPLE__
+    // Split output line from backtrace_symbols to recover function name and offset
+    // then use `nm` command line tool to get the address of the function
+    // then use `add42line` command line tool to map function address + offset to line in source code
+    static std::string TranslateBacktrace( std::string s, std::string libname )
+    {
+      constexpr char reset_shell[] = "\033[0m";
+      constexpr char green[] = "\033[32m";
+      constexpr char yellow[] = "\033[33m";
+
+      std::istringstream in(s);
+
+      std::string libname1, funcname, addr, plus_sign;
+      size_t i,offset;
+
+      in >> i >> libname1 >> addr >> funcname >> plus_sign >> std::hex >> offset;
+
+      std::stringstream out;
+
+      if(!funcname.empty() && !libname.empty())
+      {
+        std::array<char, 10240> buffer;
+        int status;
+        size_t size = buffer.size();
+        abi::__cxa_demangle(funcname.c_str(), buffer.data(), &size, &status);
+        out << "in " << yellow << buffer.data() << reset_shell;
+
+        std::string nm_command = "nm " + libname + " | grep \"" + funcname + "$\" | cut -f 1 -d ' '";
+        std::output;
+        auto exit_code = exec(nm_command, output);
+        auto fptr = std::strtoul(output.c_str(), 0, 16);
+        if(fptr == 0)
+            return out.str()+'\n';
+        std::stringstream offset_s;
+        offset_s << "0x" << std::hex << fptr+offset - 5;
+        std::string addr2line_command = std::string("atos -o ") + libname + " --fullPath " + offset_s.str();
+        exit_code = exec(addr2line_command, output);
+        if(exit_code==0)
+          out << " at " << green << output << reset_shell;
+        else
+          out << '\n';
+      }
+      else
+        out << s << '\n';
+
+      return out.str();
+    }
+#else // __APPLE__
+
+    // Split output line from backtrace_symbols to recover function name and offset
+    // then use `nm` command line tool to get the address of the function
+    // then use `addr2line` command line tool to map function address + offset to line in source code
+    static std::string TranslateBacktrace( std::string s, std::string /*dummy*/ )
+    {
+      // example line:
+      // /home/mhochsteger/install/ngs_clang/bin/../lib/libngcore.so(_ZN6ngcore11TaskManager4LoopEi+0x1e0) [0x7f2991fe1030]
+      constexpr char reset_shell[] = "\033[0m";
+      constexpr char green[] = "\033[32m";
+      constexpr char yellow[] = "\033[33m";
+
+      auto brace_open_pos = s.find('(');
+      auto brace_close_pos = s.find(')', brace_open_pos);
+      auto plus_pos = s.find('+', brace_open_pos);
+      auto bracket_open_pos = s.find('[');
+      auto bracket_close_pos = s.find(']');
+
+      auto libname = s.substr(0, brace_open_pos);
+      auto funcname = s.substr(brace_open_pos+1, plus_pos - brace_open_pos - 1);
+      auto offset = std::strtoul(s.substr(plus_pos+1, brace_close_pos - plus_pos - 1).c_str(), 0, 16);
+      auto position = std::strtoul(s.substr(bracket_open_pos+1, bracket_close_pos - bracket_open_pos - 1).c_str(), 0, 16);
+      std::stringstream out;
+
+      if(!funcname.empty())
+      {
+        std::array<char, 256> buffer;
+        int status;
+        size_t size = buffer.size();
+        abi::__cxa_demangle(funcname.c_str(), buffer.data(), &size, &status);
+        out << "in " << yellow << buffer.data() << reset_shell;
+
+        std::string nm_command = "nm " + libname + " | grep " + funcname + " | cut -f 1 -d ' '";
+        std::string output;
+        auto exit_code = exec(nm_command, output);
+        auto fptr = std::strtoul(output.c_str(), 0, 16);
+
+        std::stringstream offset_s;
+        offset_s << "0x" << std::hex << fptr+offset - 5;
+        std::string addr2line_command = std::string("addr2line -e ") + libname + " " + offset_s.str();
+        exit_code = exec(addr2line_command, output);
+        if(exit_code==0)
+          out << " at " << green << output << reset_shell;
+        else
+          out << '\n';
+      }
+      else
+        out << s << '\n';
+
+      return out.str();
+    }
+#endif // __APPLE__
+
+  } // namespace detail
+
+  std::string GetBackTrace()
+  {
+    std::stringstream result;
+    void *bt[1024];
+    int bt_size;
+    char **bt_syms;
+    int i;
+
+    bt_size = backtrace(bt, 1024);
+    bt_syms = backtrace_symbols(bt, bt_size);
+    Dl_info info;
+    for (i = 1; i < bt_size-1; i++)
+      {
+        dladdr(bt[i], &info);
+        size_t len = strlen(bt_syms[i]);
+        result << '#'<< i << '\t' << detail::TranslateBacktrace( bt_syms[i], info.dli_fname );
+      }
+    free(bt_syms);
+    return result.str();
+  }
+
+} // namespace ngcore
+
+#else // __GNUC__
+
+namespace ngcore
+{
+  std::string GetBackTrace()
+  {
+    return std::string();
+  }
+} // namespace ngcore
+
+#endif // __GNUC__

libsrc/core/exception.hpp

@@ -7,8 +7,12 @@
 
 #include "ngcore_api.hpp"  // for NGCORE_API
 
+
 namespace ngcore
 {
+
+  NGCORE_API std::string GetBackTrace();
+
   // Exception for code that shouldn't be executed
   class NGCORE_API UnreachableCodeException : public std::exception
   {
@@ -57,6 +61,7 @@ namespace ngcore
         std::stringstream str;
         str << where << ": index " << ind << " out of range [" << imin << "," << imax << ")\n";
         Append (str.str());
+        Append (GetBackTrace());
       }
 
     template<typename T>