/* BEGIN_LEGAL 

Copyright (c) 2021 Intel Corporation

  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at

      http://www.apache.org/licenses/LICENSE-2.0

  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
  
END_LEGAL */
#include <Python.h>

#include <stdio.h>
#include "xed/xed-interface.h"

#if defined(__GNUC__) || defined(__clang__)
#  include <stdint.h>
#else 
typedef unsigned __int32 uint32_t;
typedef unsigned __int64 uint64_t;
#endif

static PyObject *dis(PyObject *self,
                     PyObject *args,
                     xed_machine_mode_enum_t mmode,
                     xed_address_width_enum_t stack_addr_width)
{
    PyObject* byte_list_obj=0;
    PyObject* it=0;
    PyObject* next=0;
    char itext[XED_MAX_INSTRUCTION_BYTES];
    int pos = 0;
    xed_error_enum_t xed_error;
    xed_decoded_inst_t xedd;
#define BUFLEN  1000
    char buffer[BUFLEN];
    int ok;
    uint64_t runtime_addr=0;
    
    if (!PyArg_ParseTuple(args, "O|K", &byte_list_obj, &runtime_addr))
        return NULL;
    if (!(it = PyObject_GetIter(byte_list_obj)))
        return NULL;
    while ((next=PyIter_Next(it)) && pos < XED_MAX_INSTRUCTION_BYTES)
    {
        if (!PyLong_Check(next))
            return NULL;
        itext[pos++] = PyLong_AsUnsignedLong(next);
    }

    xed_decoded_inst_zero(&xedd);
    xed_decoded_inst_set_mode(&xedd, mmode, stack_addr_width);
    xed_error = xed_decode(&xedd, 
                           XED_STATIC_CAST(const xed_uint8_t*,itext),
                           pos);
    
    if (xed_error == XED_ERROR_NONE)
    {
        ok = xed_format_context(XED_SYNTAX_INTEL,
                                &xedd, buffer, BUFLEN, runtime_addr,
                                0, 0);
        if (ok) {
            xed_uint32_t ilen;
            ilen = xed_decoded_inst_get_length(&xedd);

            return Py_BuildValue("si", buffer, ilen);
        }
        else 
            return Py_BuildValue("si", "Disassembly error", 0);
    }
    return Py_BuildValue("si", "Decoding error", 0);
}

static PyObject *
dis64(PyObject *self, PyObject *args)
{
    return dis(self,args,XED_MACHINE_MODE_LONG_64,XED_ADDRESS_WIDTH_64b);
}
static PyObject *
dis32(PyObject *self, PyObject *args)
{
    return dis(self,args,XED_MACHINE_MODE_LEGACY_32,XED_ADDRESS_WIDTH_32b);
}


#define HELPSTR  " Arguments are:\n\t(1) a list of integers representing the code to decode/disassemble,\n\t(2) an optional runtime address.\n\tReturns a disassembly string.\n"
     
static PyMethodDef xed_methods[] = {
    {"dis64",  dis64, METH_VARARGS, "Disassemble in 64b mode."  HELPSTR },
    {"dis32",  dis32, METH_VARARGS, "Disassemble in 32b mode."  HELPSTR },
    {NULL, NULL, 0, NULL}
};

static struct PyModuleDef xed = {
    PyModuleDef_HEAD_INIT,
    "xed",    /* name of module */
    NULL,     /* module documentation, may be NULL */
    -1,       /* size of per-interpreter state of the module,
                 or -1 if the module keeps state in global variables. */
    xed_methods
};


PyMODINIT_FUNC
PyInit_xed(void)
{
    PyObject *m;

    m = PyModule_Create(&xed);
    if (m == NULL)
        return 0;
    xed_tables_init();
    return m;
}