1 /* Python memory buffer interface for reading inferior memory. 2 3 Copyright (C) 2009-2023 Free Software Foundation, Inc. 4 5 This file is part of GDB. 6 7 This program is free software; you can redistribute it and/or modify 8 it under the terms of the GNU General Public License as published by 9 the Free Software Foundation; either version 3 of the License, or 10 (at your option) any later version. 11 12 This program is distributed in the hope that it will be useful, 13 but WITHOUT ANY WARRANTY; without even the implied warranty of 14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 GNU General Public License for more details. 16 17 You should have received a copy of the GNU General Public License 18 along with this program. If not, see <http://www.gnu.org/licenses/>. */ 19 20 #include "defs.h" 21 #include "python-internal.h" 22 23 struct membuf_object { 24 PyObject_HEAD 25 26 /* Pointer to the raw data, and array of gdb_bytes. */ 27 void *buffer; 28 29 /* The address from where the data was read, held for mbpy_str. */ 30 CORE_ADDR addr; 31 32 /* The number of octets in BUFFER. */ 33 CORE_ADDR length; 34 }; 35 36 extern PyTypeObject membuf_object_type 37 CPYCHECKER_TYPE_OBJECT_FOR_TYPEDEF ("membuf_object"); 38 39 /* Wrap BUFFER, ADDRESS, and LENGTH into a gdb.Membuf object. ADDRESS is 40 the address within the inferior that the contents of BUFFER were read, 41 and LENGTH is the number of octets in BUFFER. */ 42 43 PyObject * 44 gdbpy_buffer_to_membuf (gdb::unique_xmalloc_ptr<gdb_byte> buffer, 45 CORE_ADDR address, 46 ULONGEST length) 47 { 48 gdbpy_ref<membuf_object> membuf_obj (PyObject_New (membuf_object, 49 &membuf_object_type)); 50 if (membuf_obj == nullptr) 51 return nullptr; 52 53 membuf_obj->buffer = buffer.release (); 54 membuf_obj->addr = address; 55 membuf_obj->length = length; 56 57 return PyMemoryView_FromObject ((PyObject *) membuf_obj.get ()); 58 } 59 60 /* Destructor for gdb.Membuf objects. */ 61 62 static void 63 mbpy_dealloc (PyObject *self) 64 { 65 xfree (((membuf_object *) self)->buffer); 66 Py_TYPE (self)->tp_free (self); 67 } 68 69 /* Return a description of the gdb.Membuf object. */ 70 71 static PyObject * 72 mbpy_str (PyObject *self) 73 { 74 membuf_object *membuf_obj = (membuf_object *) self; 75 76 return PyUnicode_FromFormat (_("Memory buffer for address %s, \ 77 which is %s bytes long."), 78 paddress (gdbpy_enter::get_gdbarch (), 79 membuf_obj->addr), 80 pulongest (membuf_obj->length)); 81 } 82 83 static int 84 get_buffer (PyObject *self, Py_buffer *buf, int flags) 85 { 86 membuf_object *membuf_obj = (membuf_object *) self; 87 int ret; 88 89 ret = PyBuffer_FillInfo (buf, self, membuf_obj->buffer, 90 membuf_obj->length, 0, 91 PyBUF_CONTIG); 92 93 /* Despite the documentation saying this field is a "const char *", 94 in Python 3.4 at least, it's really a "char *". */ 95 buf->format = (char *) "c"; 96 97 return ret; 98 } 99 100 /* General Python initialization callback. */ 101 102 int 103 gdbpy_initialize_membuf (void) 104 { 105 membuf_object_type.tp_new = PyType_GenericNew; 106 if (PyType_Ready (&membuf_object_type) < 0) 107 return -1; 108 109 return gdb_pymodule_addobject (gdb_module, "Membuf", 110 (PyObject *) &membuf_object_type); 111 } 112 113 static PyBufferProcs buffer_procs = 114 { 115 get_buffer 116 }; 117 118 PyTypeObject membuf_object_type = { 119 PyVarObject_HEAD_INIT (nullptr, 0) 120 "gdb.Membuf", /*tp_name*/ 121 sizeof (membuf_object), /*tp_basicsize*/ 122 0, /*tp_itemsize*/ 123 mbpy_dealloc, /*tp_dealloc*/ 124 0, /*tp_print*/ 125 0, /*tp_getattr*/ 126 0, /*tp_setattr*/ 127 0, /*tp_compare*/ 128 0, /*tp_repr*/ 129 0, /*tp_as_number*/ 130 0, /*tp_as_sequence*/ 131 0, /*tp_as_mapping*/ 132 0, /*tp_hash */ 133 0, /*tp_call*/ 134 mbpy_str, /*tp_str*/ 135 0, /*tp_getattro*/ 136 0, /*tp_setattro*/ 137 &buffer_procs, /*tp_as_buffer*/ 138 Py_TPFLAGS_DEFAULT, /*tp_flags*/ 139 "GDB memory buffer object", /*tp_doc*/ 140 0, /* tp_traverse */ 141 0, /* tp_clear */ 142 0, /* tp_richcompare */ 143 0, /* tp_weaklistoffset */ 144 0, /* tp_iter */ 145 0, /* tp_iternext */ 146 0, /* tp_methods */ 147 0, /* tp_members */ 148 0, /* tp_getset */ 149 0, /* tp_base */ 150 0, /* tp_dict */ 151 0, /* tp_descr_get */ 152 0, /* tp_descr_set */ 153 0, /* tp_dictoffset */ 154 0, /* tp_init */ 155 0, /* tp_alloc */ 156 }; 157