cea-sec/miasm

#include <Python.h>
#include <inttypes.h>
#include <stdint.h>
#include "compat_py23.h"

typedef struct {
    uint8_t is_local;
    uint64_t address;
} block_id;

typedef int (*jitted_func)(block_id*, PyObject*);


PyObject* gcc_exec_block(PyObject* self, PyObject* args)
{
    jitted_func func;
    PyObject* jitcpu;
    PyObject* func_py;
    PyObject* lbl2ptr;
    PyObject* stop_offsets;
    PyObject* retaddr = NULL;
    int status;
    block_id BlockDst;
    uint64_t max_exec_per_call = 0;
    uint64_t cpt;
    int do_cpt;


    if (!PyArg_ParseTuple(args, "OOOO|K",
                  &retaddr, &jitcpu, &lbl2ptr, &stop_offsets,
                  &max_exec_per_call))
        return NULL;

    /* The loop will decref retaddr always once */
    Py_INCREF(retaddr);

    if (max_exec_per_call == 0) {
        do_cpt = 0;
        cpt = 1;
    } else {
        do_cpt = 1;
        cpt = max_exec_per_call;
    }



    for (;;) {
        if (cpt == 0)
            return retaddr;
        if (do_cpt)
            cpt --;
        // Init
        BlockDst.is_local = 0;
        BlockDst.address = 0;

        // Get the expected jitted function address
        func_py = PyDict_GetItem(lbl2ptr, retaddr);
        if (func_py)
            func = (jitted_func) PyLong_AsVoidPtr((PyObject*) func_py);
        else {
            if (BlockDst.is_local == 1) {
                fprintf(stderr, "return on local label!\n");
                exit(EXIT_FAILURE);
            }
            // retaddr is not jitted yet
            return retaddr;
        }
        // Execute it
        status = func(&BlockDst, jitcpu);
        Py_DECREF(retaddr);
        retaddr = PyLong_FromUnsignedLongLong(BlockDst.address);

        // Check exception
        if (status)
            return retaddr;

        // Check stop offsets
        if (PySet_Contains(stop_offsets, retaddr))
            return retaddr;
    }
}



static PyMethodDef GccMethods[] = {
    {"gcc_exec_block",  gcc_exec_block, METH_VARARGS,
     "gcc exec block"},
    {NULL, NULL, 0, NULL}        /* Sentinel */
};



MOD_INIT(Jitgcc)
{
    PyObject *module = NULL;

    MOD_DEF(module, "Jitgcc", "gcc module", GccMethods);

    RET_MODULE;
}