illness.c

#include <stdio.h>
#include <inttypes.h>
#include <string.h>
#include <glib.h>

#include <mono/metadata/image.h>
#include <mono/metadata/verify.h>
#include <mono/metadata/class.h>
#include <mono/metadata/loader.h>
#include <mono/metadata/object.h>
#include <mono/metadata/appdomain.h>
#include <mono/metadata/assembly.h>
#include <mono/metadata/debug-helpers.h>
#include <mono/metadata/tokentype.h>

#include <dis/get.h>

// for monodis
gboolean substitute_with_mscorlib_p = FALSE;

static char*
token_handler (MonoDisHelper *dh, MonoMethod *method, guint32 token)
{
    // // ERROR_DECL (error);
    // char *res, *desc;
    // MonoClassField *field;
    // gpointer data = NULL;
    MonoClass *klass;
    MonoImage* image = mono_class_get_image( mono_method_get_class( method ));
    guint32 tokencode = mono_metadata_token_code(token);
    MonoMethod *cmethod;
    MonoClassField* field;
    MonoClass *retklass;
    MonoMethodDesc* mdesc;
    MonoMethodSignature* sig;
    
    return get_token(image, token, NULL);
}


//  * disasm_ins:
//  *
//  *   Produce a disassembled form of the IL instruction at IP. This is an extension
//  * of mono_disasm_code_one () which can disasm tokens, handle wrapper methods, and
//  * CEE_MONO_ opcodes.
 
FILE *output;
 
void
disasm_ins (MonoMethod *method)
{
    output = stdout;
    init_key_table ();
    
    char *dis;
    MonoDisHelper dh;
    MonoMethodHeader *header = mono_method_get_header (method);
    
    // printf("%s:", mono_method_full_name(method, TRUE));

    memset (&dh, 0, sizeof (dh));
    dh.newline = "\n";
    dh.label_format = "IL_%04x: ";
    dh.label_target = "IL_%04x";
    dh.tokener = token_handler;
    
    const unsigned char* header_code;
    uint32_t header_size;
    header_code = mono_method_header_get_code(header, &header_size, NULL);
    char* il_code = mono_disasm_code(&dh, method, header_code, header_code + header_size);

    printf("\n%s", il_code);
}

illness.cs

using System;
using System.Linq;
using System.Reflection;
using System.Reflection.Emit;
using System.Runtime.InteropServices;
using System.Runtime.CompilerServices;

public static class Illness
{  
  [DllImport ("libillness.so", EntryPoint="disasm_ins")]
  internal static extern void DisassembleMethodIL2(IntPtr m);
    
  internal static Type GetInternalType(string name)
  {
    foreach(var a in AppDomain.CurrentDomain.GetAssemblies())
    {
      var t = a.GetType(name);
      if (t != null)
        return t;
    }

    return null;
  }
  
  static FieldInfo monoMethodMhandleField = 
    Illness.GetInternalType("System.Reflection.MonoMethod").
      GetField("mhandle", BindingFlags.NonPublic |
        BindingFlags.Instance);
                                    
  static FieldInfo dynamicMethodMhandleField =
    typeof(DynamicMethod).
      GetField("mhandle", BindingFlags.NonPublic |
        BindingFlags.Instance);
        
  static IntPtr GetNativePtr(MethodInfo m)
  {
    if(m is DynamicMethod)
    {
      var rmh = (RuntimeMethodHandle)dynamicMethodMhandleField.GetValue(m);
      if(rmh.Value == IntPtr.Zero)
        throw new Exception(string.Format("DynamicMethod {0} has not been compiled. Call CreateDelegate first.", m));
      return rmh.Value;
    }
    else
    {
      return (IntPtr)monoMethodMhandleField.GetValue(m);
    }
  }
  
  public static void DisassembleIl2(MethodInfo m)
  {
    IntPtr mhandle = GetNativePtr(m);
    DisassembleMethodIL2(mhandle);
  }
  
}

program.cs

using System;
using System.Numerics;

public static class Program
{    
  public static Vector3 AddVectors(Vector3 a, Vector3 b) {
    return a + b;
  }
  
  public static void Main(string[] args)
  {
    Illness.DisassembleIl2(typeof(Program).GetMethod("AddVectors"));
  }
}

stacktrace

☭ mono Program.exe
mono_os_mutex_lock: pthread_mutex_lock failed with "Invalid argument" (22)
Stacktrace:

  at <unknown> <0xffffffff>
  at (wrapper managed-to-native) Illness.DisassembleMethodIL2 (intptr) [0x00002] in <6ec805cea31a4daa82ad7343f5670119>:0
  at Illness.DisassembleIl2 (System.Reflection.MethodInfo) [0x00007] in <6ec805cea31a4daa82ad7343f5670119>:0
  at Program.Main (string[]) [0x00026] in <702b57b0c75f465fbe1b40244ca86772>:0
  at (wrapper runtime-invoke) <Module>.runtime_invoke_void_object (object,intptr,intptr,intptr) [0x0004e] in <702b57b0c75f465fbe1b40244ca86772>:0

Native stacktrace:

	0   mono                                0x0000000104132a28 mono_handle_native_crash + 264
	1   libsystem_platform.dylib            0x00007fffe8cc3b3a _sigtramp + 26
	2   ???                                 0x0000000000000003 0x0 + 3
	3   libsystem_c.dylib                   0x00007fffe8b48420 abort + 129
	4   libmonosgen-2.0.1.dylib             0x00000001081e5939 monoeg_log_default_handler + 105
	5   libmonosgen-2.0.1.dylib             0x00000001081e5a0e monoeg_g_log + 206
	6   libmonosgen-2.0.1.dylib             0x000000010807c96f mono_assembly_load_reference + 1247
	7   libmonosgen-2.0.1.dylib             0x000000010808305d mono_class_from_typeref_checked + 717
	8   libmonosgen-2.0.1.dylib             0x00000001080c2bf0 method_from_memberref + 224
	9   libmonosgen-2.0.1.dylib             0x00000001080c1073 mono_get_method_checked + 723
	10  libmonosgen-2.0.1.dylib             0x00000001080c1437 mono_get_method_full + 23
	11  libillness.so                       0x00000001047821ef get_method_core + 63
	12  libillness.so                       0x0000000104783154 get_token + 500
	13  libmonosgen-2.0.1.dylib             0x000000010809f8f6 dis_one + 278
	14  libmonosgen-2.0.1.dylib             0x000000010809fc84 mono_disasm_code + 84
	15  libillness.so                       0x000000010477df4f disasm_ins + 159
	16  ???                                 0x0000000104621e3d 0x0 + 4368506429
	17  mono                                0x0000000104087117 mono_jit_runtime_invoke + 1383
	18  mono                                0x000000010427fbb4 do_runtime_invoke + 84
	19  mono                                0x0000000104283179 do_exec_main_checked + 137
	20  mono                                0x00000001040f493f mono_jit_exec + 287
	21  mono                                0x00000001040f78bd mono_main + 11069
	22  mono                                0x0000000104076acd main + 253
	23  mono                                0x00000001040769c4 start + 52