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Diffstat (limited to 'plugins/kaitai/python/records/item.c')
-rw-r--r-- | plugins/kaitai/python/records/item.c | 394 |
1 files changed, 394 insertions, 0 deletions
diff --git a/plugins/kaitai/python/records/item.c b/plugins/kaitai/python/records/item.c new file mode 100644 index 0000000..84c2c58 --- /dev/null +++ b/plugins/kaitai/python/records/item.c @@ -0,0 +1,394 @@ + +/* Chrysalide - Outil d'analyse de fichiers binaires + * item.h - équivalent Python du fichier "plugins/kaitai/parsers/item.h" + * + * Copyright (C) 2019 Cyrille Bagard + * + * This file is part of Chrysalide. + * + * Chrysalide is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 3 of the License, or + * (at your option) any later version. + * + * Chrysalide is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + + +#include "item.h" + + +#include <assert.h> +#include <pygobject.h> + + +#include <i18n.h> +#include <plugins/pychrysalide/access.h> +#include <plugins/pychrysalide/helpers.h> +#include <plugins/pychrysalide/analysis/content.h> +#include <plugins/pychrysalide/arch/vmpa.h> +#include <plugins/yaml/python/node.h> + + +#include "../record.h" +#include "../parsers/attribute.h" +#include "../../records/item-int.h" + + + +CREATE_DYN_CONSTRUCTOR(record_item, G_TYPE_RECORD_ITEM); + +/* Initialise une instance sur la base du dérivé de GObject. */ +static int py_record_item_init(PyObject *, PyObject *, PyObject *); + +/* Lit la série d'octets d'un élément Kaitai entier représenté. */ +static PyObject *py_record_item_get_truncated_bytes(PyObject *, void *); + +/* Lit la valeur d'un élément Kaitai entier représenté. */ +static PyObject *py_record_item_get_value(PyObject *, void *); + + + +/****************************************************************************** +* * +* Paramètres : self = objet à initialiser (théoriquement). * +* args = arguments fournis à l'appel. * +* kwds = arguments de type key=val fournis. * +* * +* Description : Initialise une instance sur la base du dérivé de GObject. * +* * +* Retour : 0. * +* * +* Remarques : - * +* * +******************************************************************************/ + +static int py_record_item_init(PyObject *self, PyObject *args, PyObject *kwds) +{ + GKaitaiAttribute *attrib; /* Attribut défini créateur */ + GBinContent *content; /* Contenu binaire analysé */ + mrange_t range; /* Espace couvert */ + SourceEndian endian; /* Boutisme à observer */ + int ret; /* Bilan de lecture des args. */ + GRecordItem *item; /* Création GLib à transmettre */ + +#define RECORD_ITEM_DOC \ + "The RecordItem class remembers a match between a described attribute and" \ + " its concret value read from parsed binary data." \ + "\n" \ + "Instances can be created using the following constructor:\n" \ + "\n" \ + " RecordItem(content, range, endian, attrib)" \ + "\n" \ + "Where the *attrib* arguments refers to a" \ + " pychrysalide.plugins.kaitai.parsers.KaitaiAttribute instance as the" \ + " creator of the newly created object, *content* points to a" \ + " pychrysalide.analysis.BinContent instance, *range* is a" \ + " pychrysalide.arch.mrange object, *endian* states with a" \ + " pychrysalide.analysis.BinContent.SourceEndian hint the endianness used" \ + " to read integer values." + + /* Récupération des paramètres */ + + ret = PyArg_ParseTuple(args, "O&O&O&", + convert_to_kaitai_attribute, &attrib, + convert_to_binary_content, &content, + convert_any_to_mrange, &range, + convert_to_binary_content, &endian); + if (!ret) return -1; + + /* Initialisation d'un objet GLib */ + + ret = forward_pygobjet_init(self); + if (ret == -1) return -1; + + /* Eléments de base */ + + item = G_RECORD_ITEM(pygobject_get(self)); + + if (!g_record_item_create(item, attrib, content, &range, endian)) + { + PyErr_SetString(PyExc_ValueError, _("Unable to create record item.")); + return -1; + } + + return 0; + +} + + +/****************************************************************************** +* * +* Paramètres : self = objet Python concerné par l'appel. * +* closure = non utilisé ici. * +* * +* Description : Lit la série d'octets d'un élément Kaitai entier représenté. * +* * +* Retour : Bilan de l'opération. * +* * +* Remarques : - * +* * +******************************************************************************/ + +static PyObject *py_record_item_get_truncated_bytes(PyObject *self, void *closure) +{ + PyObject *result; /* Valeur à retourner */ + GRecordItem *item; /* Version native de l'élément */ + bool status; /* Bilan d'opération */ + bin_t *out; /* Données brutes à transmettre*/ + size_t len; /* Quantité de ces données */ + +#define RECORD_ITEM_TRUNCATED_BYTES_ATTRIB PYTHON_GET_DEF_FULL \ +( \ + truncated_bytes, py_record_item, \ + "Raw bytes carried by the item (truncated if a separator" \ + " is defined in the linked attribute), or None if irrelevant" \ + " regarding to the type of the attribute." \ +) + + item = G_RECORD_ITEM(pygobject_get(self)); + + status = g_record_item_get_truncated_bytes(item, &out, &len); + + if (status) + { + result = PyBytes_FromStringAndSize((char *)out, len); + free(out); + } + else + { + result = Py_None; + Py_INCREF(result); + } + + return result; + +} + + +/****************************************************************************** +* * +* Paramètres : self = objet Python concerné par l'appel. * +* closure = non utilisé ici. * +* * +* Description : Lit la valeur d'un élément Kaitai entier représenté. * +* * +* Retour : Bilan de l'opération. * +* * +* Remarques : - * +* * +******************************************************************************/ + +static PyObject *py_record_item_get_value(PyObject *self, void *closure) +{ + PyObject *result; /* Valeur à retourner */ + GRecordItem *item; /* Version native de l'élément */ + resolved_value_t resolved; /* Valeur sous forme générique */ + bool status; /* Bilan d'opération */ + +#define RECORD_ITEM_VALUE_ATTRIB PYTHON_GET_DEF_FULL \ +( \ + value, py_record_item, \ + "Carried value (as integer, bytes), or None in case of error." \ +) + + result = NULL; + + item = G_RECORD_ITEM(pygobject_get(self)); + + status = g_record_item_get_value(item, &resolved); + + if (status) + switch (resolved.type) + { + case GVT_ERROR: + assert(false); + PyErr_Format(PyExc_RuntimeError, + _("Error got while parsing Kaitai definition should not have been exported!")); + result = NULL; + break; + + case GVT_UNSIGNED_INTEGER: + result = PyLong_FromUnsignedLongLong(resolved.unsigned_integer); + break; + + case GVT_SIGNED_INTEGER: + result = PyLong_FromLongLong(resolved.signed_integer); + break; + + case GVT_FLOAT: + result = PyFloat_FromDouble(resolved.floating_number); + break; + + case GVT_BOOLEAN: + result = resolved.status ? Py_True : Py_False; + Py_INCREF(result); + break; + + case GVT_BYTES: + result = PyBytes_FromStringAndSize(resolved.bytes.data, resolved.bytes.len); + exit_szstr(&resolved.bytes); + break; + + case GVT_ARRAY: + result = pygobject_new(G_OBJECT(resolved.array)); + break; + + case GVT_RECORD: + result = pygobject_new(G_OBJECT(resolved.record)); + break; + + case GVT_STREAM: + result = pygobject_new(G_OBJECT(resolved.stream)); + break; + + } + + else + { + result = Py_None; + Py_INCREF(result); + } + + return result; + +} + + +/****************************************************************************** +* * +* Paramètres : - * +* * +* Description : Fournit un accès à une définition de type à diffuser. * +* * +* Retour : Définition d'objet pour Python. * +* * +* Remarques : - * +* * +******************************************************************************/ + +PyTypeObject *get_python_record_item_type(void) +{ + static PyMethodDef py_record_item_methods[] = { + { NULL } + }; + + static PyGetSetDef py_record_item_getseters[] = { + RECORD_ITEM_TRUNCATED_BYTES_ATTRIB, + RECORD_ITEM_VALUE_ATTRIB, + { NULL } + }; + + static PyTypeObject py_record_item_type = { + + PyVarObject_HEAD_INIT(NULL, 0) + + .tp_name = "pychrysalide.plugins.kaitai.records.RecordItem", + .tp_basicsize = sizeof(PyGObject), + + .tp_flags = Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE, + + .tp_doc = RECORD_ITEM_DOC, + + .tp_methods = py_record_item_methods, + .tp_getset = py_record_item_getseters, + + .tp_init = py_record_item_init, + .tp_new = py_record_item_new, + + }; + + return &py_record_item_type; + +} + + +/****************************************************************************** +* * +* Paramètres : - * +* * +* Description : Prend en charge l'objet 'pychrysalide....records.RecordItem. * +* * +* Retour : Bilan de l'opération. * +* * +* Remarques : - * +* * +******************************************************************************/ + +bool ensure_python_record_item_is_registered(void) +{ + PyTypeObject *type; /* Type Python 'RecordItem' */ + PyObject *module; /* Module à recompléter */ + PyObject *dict; /* Dictionnaire du module */ + + type = get_python_record_item_type(); + + if (!PyType_HasFeature(type, Py_TPFLAGS_READY)) + { + module = get_access_to_python_module("pychrysalide.plugins.kaitai.records"); + + dict = PyModule_GetDict(module); + + if (!ensure_python_match_record_is_registered()) + return false; + + if (!register_class_for_pygobject(dict, G_TYPE_RECORD_ITEM, type)) + return false; + + } + + return true; + +} + + +/****************************************************************************** +* * +* Paramètres : arg = argument quelconque à tenter de convertir. * +* dst = destination des valeurs récupérées en cas de succès. * +* * +* Description : Tente de convertir en correspondance attribut/binaire. * +* * +* Retour : Bilan de l'opération, voire indications supplémentaires. * +* * +* Remarques : - * +* * +******************************************************************************/ + +int convert_to_record_item(PyObject *arg, void *dst) +{ + int result; /* Bilan à retourner */ + + result = PyObject_IsInstance(arg, (PyObject *)get_python_record_item_type()); + + switch (result) + { + case -1: + /* L'exception est déjà fixée par Python */ + result = 0; + break; + + case 0: + PyErr_SetString(PyExc_TypeError, "unable to convert the provided argument to record item"); + break; + + case 1: + *((GRecordItem **)dst) = G_RECORD_ITEM(pygobject_get(arg)); + break; + + default: + assert(false); + break; + + } + + return result; + +} |