1 /* General utility routines for GDB/Python. 2 3 Copyright (C) 2008-2012 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 "charset.h" 22 #include "value.h" 23 #include "python-internal.h" 24 25 26 /* This is a cleanup function which decrements the refcount on a 27 Python object. */ 28 29 static void 30 py_decref (void *p) 31 { 32 PyObject *py = p; 33 34 /* Note that we need the extra braces in this 'if' to avoid a 35 warning from gcc. */ 36 if (py) 37 { 38 Py_DECREF (py); 39 } 40 } 41 42 /* Return a new cleanup which will decrement the Python object's 43 refcount when run. */ 44 45 struct cleanup * 46 make_cleanup_py_decref (PyObject *py) 47 { 48 return make_cleanup (py_decref, (void *) py); 49 } 50 51 /* Converts a Python 8-bit string to a unicode string object. Assumes the 52 8-bit string is in the host charset. If an error occurs during conversion, 53 returns NULL with a python exception set. 54 55 As an added bonus, the functions accepts a unicode string and returns it 56 right away, so callers don't need to check which kind of string they've 57 got. 58 59 If the given object is not one of the mentioned string types, NULL is 60 returned, with the TypeError python exception set. */ 61 PyObject * 62 python_string_to_unicode (PyObject *obj) 63 { 64 PyObject *unicode_str; 65 66 /* If obj is already a unicode string, just return it. 67 I wish life was always that simple... */ 68 if (PyUnicode_Check (obj)) 69 { 70 unicode_str = obj; 71 Py_INCREF (obj); 72 } 73 74 else if (PyString_Check (obj)) 75 unicode_str = PyUnicode_FromEncodedObject (obj, host_charset (), NULL); 76 else 77 { 78 PyErr_SetString (PyExc_TypeError, 79 _("Expected a string or unicode object.")); 80 unicode_str = NULL; 81 } 82 83 return unicode_str; 84 } 85 86 /* Returns a newly allocated string with the contents of the given unicode 87 string object converted to CHARSET. If an error occurs during the 88 conversion, NULL will be returned and a python exception will be set. 89 90 The caller is responsible for xfree'ing the string. */ 91 static char * 92 unicode_to_encoded_string (PyObject *unicode_str, const char *charset) 93 { 94 char *result; 95 PyObject *string; 96 97 /* Translate string to named charset. */ 98 string = PyUnicode_AsEncodedString (unicode_str, charset, NULL); 99 if (string == NULL) 100 return NULL; 101 102 result = xstrdup (PyString_AsString (string)); 103 104 Py_DECREF (string); 105 106 return result; 107 } 108 109 /* Returns a PyObject with the contents of the given unicode string 110 object converted to a named charset. If an error occurs during 111 the conversion, NULL will be returned and a python exception will 112 be set. */ 113 static PyObject * 114 unicode_to_encoded_python_string (PyObject *unicode_str, const char *charset) 115 { 116 PyObject *string; 117 118 /* Translate string to named charset. */ 119 string = PyUnicode_AsEncodedString (unicode_str, charset, NULL); 120 if (string == NULL) 121 return NULL; 122 123 return string; 124 } 125 126 /* Returns a newly allocated string with the contents of the given unicode 127 string object converted to the target's charset. If an error occurs during 128 the conversion, NULL will be returned and a python exception will be set. 129 130 The caller is responsible for xfree'ing the string. */ 131 char * 132 unicode_to_target_string (PyObject *unicode_str) 133 { 134 return unicode_to_encoded_string (unicode_str, 135 target_charset (python_gdbarch)); 136 } 137 138 /* Returns a PyObject with the contents of the given unicode string 139 object converted to the target's charset. If an error occurs 140 during the conversion, NULL will be returned and a python exception 141 will be set. */ 142 PyObject * 143 unicode_to_target_python_string (PyObject *unicode_str) 144 { 145 return unicode_to_encoded_python_string (unicode_str, 146 target_charset (python_gdbarch)); 147 } 148 149 /* Converts a python string (8-bit or unicode) to a target string in 150 the target's charset. Returns NULL on error, with a python exception set. 151 152 The caller is responsible for xfree'ing the string. */ 153 char * 154 python_string_to_target_string (PyObject *obj) 155 { 156 PyObject *str; 157 char *result; 158 159 str = python_string_to_unicode (obj); 160 if (str == NULL) 161 return NULL; 162 163 result = unicode_to_target_string (str); 164 Py_DECREF (str); 165 return result; 166 } 167 168 /* Converts a python string (8-bit or unicode) to a target string in the 169 target's charset. Returns NULL on error, with a python exception 170 set. */ 171 PyObject * 172 python_string_to_target_python_string (PyObject *obj) 173 { 174 PyObject *str; 175 PyObject *result; 176 177 str = python_string_to_unicode (obj); 178 if (str == NULL) 179 return NULL; 180 181 result = unicode_to_target_python_string (str); 182 Py_DECREF (str); 183 return result; 184 } 185 186 /* Converts a python string (8-bit or unicode) to a target string in 187 the host's charset. Returns NULL on error, with a python exception set. 188 189 The caller is responsible for xfree'ing the string. */ 190 char * 191 python_string_to_host_string (PyObject *obj) 192 { 193 PyObject *str; 194 char *result; 195 196 str = python_string_to_unicode (obj); 197 if (str == NULL) 198 return NULL; 199 200 result = unicode_to_encoded_string (str, host_charset ()); 201 Py_DECREF (str); 202 return result; 203 } 204 205 /* Converts a target string of LENGTH bytes in the target's charset to a 206 Python Unicode string. If LENGTH is -1, convert until a null byte is found. 207 208 Returns NULL on error, with a python exception set. */ 209 PyObject * 210 target_string_to_unicode (const gdb_byte *str, int length) 211 { 212 if (length == -1) 213 length = strlen (str); 214 215 return PyUnicode_Decode (str, length, target_charset (python_gdbarch), NULL); 216 } 217 218 /* Return true if OBJ is a Python string or unicode object, false 219 otherwise. */ 220 221 int 222 gdbpy_is_string (PyObject *obj) 223 { 224 return PyString_Check (obj) || PyUnicode_Check (obj); 225 } 226 227 /* Return the string representation of OBJ, i.e., str (obj). 228 Space for the result is malloc'd, the caller must free. 229 If the result is NULL a python error occurred, the caller must clear it. */ 230 231 char * 232 gdbpy_obj_to_string (PyObject *obj) 233 { 234 PyObject *str_obj = PyObject_Str (obj); 235 236 if (str_obj != NULL) 237 { 238 char *msg = xstrdup (PyString_AsString (str_obj)); 239 240 Py_DECREF (str_obj); 241 return msg; 242 } 243 244 return NULL; 245 } 246 247 /* Return the string representation of the exception represented by 248 TYPE, VALUE which is assumed to have been obtained with PyErr_Fetch, 249 i.e., the error indicator is currently clear. 250 Space for the result is malloc'd, the caller must free. 251 If the result is NULL a python error occurred, the caller must clear it. */ 252 253 char * 254 gdbpy_exception_to_string (PyObject *ptype, PyObject *pvalue) 255 { 256 char *str; 257 258 /* There are a few cases to consider. 259 For example: 260 pvalue is a string when PyErr_SetString is used. 261 pvalue is not a string when raise "foo" is used, instead it is None 262 and ptype is "foo". 263 So the algorithm we use is to print `str (pvalue)' if it's not 264 None, otherwise we print `str (ptype)'. 265 Using str (aka PyObject_Str) will fetch the error message from 266 gdb.GdbError ("message"). */ 267 268 if (pvalue && pvalue != Py_None) 269 str = gdbpy_obj_to_string (pvalue); 270 else 271 str = gdbpy_obj_to_string (ptype); 272 273 return str; 274 } 275 276 /* Convert a GDB exception to the appropriate Python exception. 277 278 This sets the Python error indicator, and returns NULL. */ 279 280 PyObject * 281 gdbpy_convert_exception (struct gdb_exception exception) 282 { 283 PyObject *exc_class; 284 285 if (exception.reason == RETURN_QUIT) 286 exc_class = PyExc_KeyboardInterrupt; 287 else if (exception.error == MEMORY_ERROR) 288 exc_class = gdbpy_gdb_memory_error; 289 else 290 exc_class = gdbpy_gdb_error; 291 292 return PyErr_Format (exc_class, "%s", exception.message); 293 } 294 295 /* Converts OBJ to a CORE_ADDR value. 296 297 Returns 1 on success or 0 on failure, with a Python exception set. This 298 function can also throw GDB exceptions. 299 */ 300 301 int 302 get_addr_from_python (PyObject *obj, CORE_ADDR *addr) 303 { 304 if (gdbpy_is_value_object (obj)) 305 *addr = value_as_address (value_object_to_value (obj)); 306 else 307 { 308 PyObject *num = PyNumber_Long (obj); 309 gdb_py_ulongest val; 310 311 if (num == NULL) 312 return 0; 313 314 val = gdb_py_long_as_ulongest (num); 315 Py_XDECREF (num); 316 if (PyErr_Occurred ()) 317 return 0; 318 319 if (sizeof (val) > sizeof (CORE_ADDR) && ((CORE_ADDR) val) != val) 320 { 321 PyErr_SetString (PyExc_ValueError, 322 _("Overflow converting to address.")); 323 return 0; 324 } 325 326 *addr = val; 327 } 328 329 return 1; 330 } 331 332 /* Convert a LONGEST to the appropriate Python object -- either an 333 integer object or a long object, depending on its value. */ 334 335 PyObject * 336 gdb_py_object_from_longest (LONGEST l) 337 { 338 #ifdef HAVE_LONG_LONG /* Defined by Python. */ 339 /* If we have 'long long', and the value overflows a 'long', use a 340 Python Long; otherwise use a Python Int. */ 341 if (sizeof (l) > sizeof (long) 342 && (l > PyInt_GetMax () || l < (- (LONGEST) PyInt_GetMax ()) - 1)) 343 return PyLong_FromLongLong (l); 344 #endif 345 return PyInt_FromLong (l); 346 } 347 348 /* Convert a ULONGEST to the appropriate Python object -- either an 349 integer object or a long object, depending on its value. */ 350 351 PyObject * 352 gdb_py_object_from_ulongest (ULONGEST l) 353 { 354 #ifdef HAVE_LONG_LONG /* Defined by Python. */ 355 /* If we have 'long long', and the value overflows a 'long', use a 356 Python Long; otherwise use a Python Int. */ 357 if (sizeof (l) > sizeof (unsigned long) && l > PyInt_GetMax ()) 358 return PyLong_FromUnsignedLongLong (l); 359 #endif 360 361 if (l > PyInt_GetMax ()) 362 return PyLong_FromUnsignedLong (l); 363 364 return PyInt_FromLong (l); 365 } 366 367 /* Like PyInt_AsLong, but returns 0 on failure, 1 on success, and puts 368 the value into an out parameter. */ 369 370 int 371 gdb_py_int_as_long (PyObject *obj, long *result) 372 { 373 *result = PyInt_AsLong (obj); 374 return ! (*result == -1 && PyErr_Occurred ()); 375 } 376