| 1 | /* Helper routines for parsing XML using Expat. |
| 2 | |
| 3 | Copyright (C) 2006, 2007, 2008, 2009 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 "gdbcmd.h" |
| 22 | #include "exceptions.h" |
| 23 | #include "xml-support.h" |
| 24 | |
| 25 | #include "gdb_string.h" |
| 26 | #include "safe-ctype.h" |
| 27 | |
| 28 | /* Debugging flag. */ |
| 29 | static int debug_xml; |
| 30 | |
| 31 | /* The contents of this file are only useful if XML support is |
| 32 | available. */ |
| 33 | #ifdef HAVE_LIBEXPAT |
| 34 | |
| 35 | #include "gdb_expat.h" |
| 36 | |
| 37 | /* The maximum depth of <xi:include> nesting. No need to be miserly, |
| 38 | we just want to avoid running out of stack on loops. */ |
| 39 | #define MAX_XINCLUDE_DEPTH 30 |
| 40 | |
| 41 | /* Simplified XML parser infrastructure. */ |
| 42 | |
| 43 | /* A parsing level -- used to keep track of the current element |
| 44 | nesting. */ |
| 45 | struct scope_level |
| 46 | { |
| 47 | /* Elements we allow at this level. */ |
| 48 | const struct gdb_xml_element *elements; |
| 49 | |
| 50 | /* The element which we are within. */ |
| 51 | const struct gdb_xml_element *element; |
| 52 | |
| 53 | /* Mask of which elements we've seen at this level (used for |
| 54 | optional and repeatable checking). */ |
| 55 | unsigned int seen; |
| 56 | |
| 57 | /* Body text accumulation. */ |
| 58 | struct obstack *body; |
| 59 | }; |
| 60 | typedef struct scope_level scope_level_s; |
| 61 | DEF_VEC_O(scope_level_s); |
| 62 | |
| 63 | /* The parser itself, and our additional state. */ |
| 64 | struct gdb_xml_parser |
| 65 | { |
| 66 | XML_Parser expat_parser; /* The underlying expat parser. */ |
| 67 | |
| 68 | const char *name; /* Name of this parser. */ |
| 69 | void *user_data; /* The user's callback data, for handlers. */ |
| 70 | |
| 71 | VEC(scope_level_s) *scopes; /* Scoping stack. */ |
| 72 | |
| 73 | struct gdb_exception error; /* A thrown error, if any. */ |
| 74 | int last_line; /* The line of the thrown error, or 0. */ |
| 75 | |
| 76 | const char *dtd_name; /* The name of the expected / default DTD, |
| 77 | if specified. */ |
| 78 | int is_xinclude; /* Are we the special <xi:include> parser? */ |
| 79 | }; |
| 80 | |
| 81 | /* Process some body text. We accumulate the text for later use; it's |
| 82 | wrong to do anything with it immediately, because a single block of |
| 83 | text might be broken up into multiple calls to this function. */ |
| 84 | |
| 85 | static void |
| 86 | gdb_xml_body_text (void *data, const XML_Char *text, int length) |
| 87 | { |
| 88 | struct gdb_xml_parser *parser = data; |
| 89 | struct scope_level *scope = VEC_last (scope_level_s, parser->scopes); |
| 90 | |
| 91 | if (parser->error.reason < 0) |
| 92 | return; |
| 93 | |
| 94 | if (scope->body == NULL) |
| 95 | { |
| 96 | scope->body = XZALLOC (struct obstack); |
| 97 | obstack_init (scope->body); |
| 98 | } |
| 99 | |
| 100 | obstack_grow (scope->body, text, length); |
| 101 | } |
| 102 | |
| 103 | /* Issue a debugging message from one of PARSER's handlers. */ |
| 104 | |
| 105 | void |
| 106 | gdb_xml_debug (struct gdb_xml_parser *parser, const char *format, ...) |
| 107 | { |
| 108 | int line = XML_GetCurrentLineNumber (parser->expat_parser); |
| 109 | va_list ap; |
| 110 | char *message; |
| 111 | |
| 112 | if (!debug_xml) |
| 113 | return; |
| 114 | |
| 115 | va_start (ap, format); |
| 116 | message = xstrvprintf (format, ap); |
| 117 | if (line) |
| 118 | fprintf_unfiltered (gdb_stderr, "%s (line %d): %s\n", |
| 119 | parser->name, line, message); |
| 120 | else |
| 121 | fprintf_unfiltered (gdb_stderr, "%s: %s\n", |
| 122 | parser->name, message); |
| 123 | xfree (message); |
| 124 | } |
| 125 | |
| 126 | /* Issue an error message from one of PARSER's handlers, and stop |
| 127 | parsing. */ |
| 128 | |
| 129 | void |
| 130 | gdb_xml_error (struct gdb_xml_parser *parser, const char *format, ...) |
| 131 | { |
| 132 | int line = XML_GetCurrentLineNumber (parser->expat_parser); |
| 133 | va_list ap; |
| 134 | |
| 135 | parser->last_line = line; |
| 136 | va_start (ap, format); |
| 137 | throw_verror (XML_PARSE_ERROR, format, ap); |
| 138 | } |
| 139 | |
| 140 | /* Clean up a vector of parsed attribute values. */ |
| 141 | |
| 142 | static void |
| 143 | gdb_xml_values_cleanup (void *data) |
| 144 | { |
| 145 | VEC(gdb_xml_value_s) **values = data; |
| 146 | struct gdb_xml_value *value; |
| 147 | int ix; |
| 148 | |
| 149 | for (ix = 0; VEC_iterate (gdb_xml_value_s, *values, ix, value); ix++) |
| 150 | xfree (value->value); |
| 151 | VEC_free (gdb_xml_value_s, *values); |
| 152 | } |
| 153 | |
| 154 | /* Handle the start of an element. DATA is our local XML parser, NAME |
| 155 | is the element, and ATTRS are the names and values of this |
| 156 | element's attributes. */ |
| 157 | |
| 158 | static void |
| 159 | gdb_xml_start_element (void *data, const XML_Char *name, |
| 160 | const XML_Char **attrs) |
| 161 | { |
| 162 | struct gdb_xml_parser *parser = data; |
| 163 | struct scope_level *scope; |
| 164 | struct scope_level new_scope; |
| 165 | const struct gdb_xml_element *element; |
| 166 | const struct gdb_xml_attribute *attribute; |
| 167 | VEC(gdb_xml_value_s) *attributes = NULL; |
| 168 | unsigned int seen; |
| 169 | struct cleanup *back_to; |
| 170 | |
| 171 | /* Push an error scope. If we return or throw an exception before |
| 172 | filling this in, it will tell us to ignore children of this |
| 173 | element. */ |
| 174 | VEC_reserve (scope_level_s, parser->scopes, 1); |
| 175 | scope = VEC_last (scope_level_s, parser->scopes); |
| 176 | memset (&new_scope, 0, sizeof (new_scope)); |
| 177 | VEC_quick_push (scope_level_s, parser->scopes, &new_scope); |
| 178 | |
| 179 | gdb_xml_debug (parser, _("Entering element <%s>"), name); |
| 180 | |
| 181 | /* Find this element in the list of the current scope's allowed |
| 182 | children. Record that we've seen it. */ |
| 183 | |
| 184 | seen = 1; |
| 185 | for (element = scope->elements; element && element->name; |
| 186 | element++, seen <<= 1) |
| 187 | if (strcmp (element->name, name) == 0) |
| 188 | break; |
| 189 | |
| 190 | if (element == NULL || element->name == NULL) |
| 191 | { |
| 192 | /* If we're working on XInclude, <xi:include> can be the child |
| 193 | of absolutely anything. Copy the previous scope's element |
| 194 | list into the new scope even if there was no match. */ |
| 195 | if (parser->is_xinclude) |
| 196 | { |
| 197 | struct scope_level *unknown_scope; |
| 198 | |
| 199 | XML_DefaultCurrent (parser->expat_parser); |
| 200 | |
| 201 | unknown_scope = VEC_last (scope_level_s, parser->scopes); |
| 202 | unknown_scope->elements = scope->elements; |
| 203 | return; |
| 204 | } |
| 205 | |
| 206 | gdb_xml_debug (parser, _("Element <%s> unknown"), name); |
| 207 | return; |
| 208 | } |
| 209 | |
| 210 | if (!(element->flags & GDB_XML_EF_REPEATABLE) && (seen & scope->seen)) |
| 211 | gdb_xml_error (parser, _("Element <%s> only expected once"), name); |
| 212 | |
| 213 | scope->seen |= seen; |
| 214 | |
| 215 | back_to = make_cleanup (gdb_xml_values_cleanup, &attributes); |
| 216 | |
| 217 | for (attribute = element->attributes; |
| 218 | attribute != NULL && attribute->name != NULL; |
| 219 | attribute++) |
| 220 | { |
| 221 | const char *val = NULL; |
| 222 | const XML_Char **p; |
| 223 | void *parsed_value; |
| 224 | struct gdb_xml_value new_value; |
| 225 | |
| 226 | for (p = attrs; *p != NULL; p += 2) |
| 227 | if (!strcmp (attribute->name, p[0])) |
| 228 | { |
| 229 | val = p[1]; |
| 230 | break; |
| 231 | } |
| 232 | |
| 233 | if (*p != NULL && val == NULL) |
| 234 | { |
| 235 | gdb_xml_debug (parser, _("Attribute \"%s\" missing a value"), |
| 236 | attribute->name); |
| 237 | continue; |
| 238 | } |
| 239 | |
| 240 | if (*p == NULL && !(attribute->flags & GDB_XML_AF_OPTIONAL)) |
| 241 | { |
| 242 | gdb_xml_error (parser, _("Required attribute \"%s\" of " |
| 243 | "<%s> not specified"), |
| 244 | attribute->name, element->name); |
| 245 | continue; |
| 246 | } |
| 247 | |
| 248 | if (*p == NULL) |
| 249 | continue; |
| 250 | |
| 251 | gdb_xml_debug (parser, _("Parsing attribute %s=\"%s\""), |
| 252 | attribute->name, val); |
| 253 | |
| 254 | if (attribute->handler) |
| 255 | parsed_value = attribute->handler (parser, attribute, val); |
| 256 | else |
| 257 | parsed_value = xstrdup (val); |
| 258 | |
| 259 | new_value.name = attribute->name; |
| 260 | new_value.value = parsed_value; |
| 261 | VEC_safe_push (gdb_xml_value_s, attributes, &new_value); |
| 262 | } |
| 263 | |
| 264 | /* Check for unrecognized attributes. */ |
| 265 | if (debug_xml) |
| 266 | { |
| 267 | const XML_Char **p; |
| 268 | |
| 269 | for (p = attrs; *p != NULL; p += 2) |
| 270 | { |
| 271 | for (attribute = element->attributes; |
| 272 | attribute != NULL && attribute->name != NULL; |
| 273 | attribute++) |
| 274 | if (strcmp (attribute->name, *p) == 0) |
| 275 | break; |
| 276 | |
| 277 | if (attribute == NULL || attribute->name == NULL) |
| 278 | gdb_xml_debug (parser, _("Ignoring unknown attribute %s"), *p); |
| 279 | } |
| 280 | } |
| 281 | |
| 282 | /* Call the element handler if there is one. */ |
| 283 | if (element->start_handler) |
| 284 | element->start_handler (parser, element, parser->user_data, attributes); |
| 285 | |
| 286 | /* Fill in a new scope level. */ |
| 287 | scope = VEC_last (scope_level_s, parser->scopes); |
| 288 | scope->element = element; |
| 289 | scope->elements = element->children; |
| 290 | |
| 291 | do_cleanups (back_to); |
| 292 | } |
| 293 | |
| 294 | /* Wrapper for gdb_xml_start_element, to prevent throwing exceptions |
| 295 | through expat. */ |
| 296 | |
| 297 | static void |
| 298 | gdb_xml_start_element_wrapper (void *data, const XML_Char *name, |
| 299 | const XML_Char **attrs) |
| 300 | { |
| 301 | struct gdb_xml_parser *parser = data; |
| 302 | volatile struct gdb_exception ex; |
| 303 | |
| 304 | if (parser->error.reason < 0) |
| 305 | return; |
| 306 | |
| 307 | TRY_CATCH (ex, RETURN_MASK_ALL) |
| 308 | { |
| 309 | gdb_xml_start_element (data, name, attrs); |
| 310 | } |
| 311 | if (ex.reason < 0) |
| 312 | { |
| 313 | parser->error = ex; |
| 314 | #ifdef HAVE_XML_STOPPARSER |
| 315 | XML_StopParser (parser->expat_parser, XML_FALSE); |
| 316 | #endif |
| 317 | } |
| 318 | } |
| 319 | |
| 320 | /* Handle the end of an element. DATA is our local XML parser, and |
| 321 | NAME is the current element. */ |
| 322 | |
| 323 | static void |
| 324 | gdb_xml_end_element (void *data, const XML_Char *name) |
| 325 | { |
| 326 | struct gdb_xml_parser *parser = data; |
| 327 | struct scope_level *scope = VEC_last (scope_level_s, parser->scopes); |
| 328 | const struct gdb_xml_element *element; |
| 329 | unsigned int seen; |
| 330 | |
| 331 | gdb_xml_debug (parser, _("Leaving element <%s>"), name); |
| 332 | |
| 333 | for (element = scope->elements, seen = 1; |
| 334 | element != NULL && element->name != NULL; |
| 335 | element++, seen <<= 1) |
| 336 | if ((scope->seen & seen) == 0 |
| 337 | && (element->flags & GDB_XML_EF_OPTIONAL) == 0) |
| 338 | gdb_xml_error (parser, _("Required element <%s> is missing"), |
| 339 | element->name); |
| 340 | |
| 341 | /* Call the element processor. */ |
| 342 | if (scope->element != NULL && scope->element->end_handler) |
| 343 | { |
| 344 | char *body; |
| 345 | |
| 346 | if (scope->body == NULL) |
| 347 | body = ""; |
| 348 | else |
| 349 | { |
| 350 | int length; |
| 351 | |
| 352 | length = obstack_object_size (scope->body); |
| 353 | obstack_1grow (scope->body, '\0'); |
| 354 | body = obstack_finish (scope->body); |
| 355 | |
| 356 | /* Strip leading and trailing whitespace. */ |
| 357 | while (length > 0 && ISSPACE (body[length-1])) |
| 358 | body[--length] = '\0'; |
| 359 | while (*body && ISSPACE (*body)) |
| 360 | body++; |
| 361 | } |
| 362 | |
| 363 | scope->element->end_handler (parser, scope->element, parser->user_data, |
| 364 | body); |
| 365 | } |
| 366 | else if (scope->element == NULL) |
| 367 | XML_DefaultCurrent (parser->expat_parser); |
| 368 | |
| 369 | /* Pop the scope level. */ |
| 370 | if (scope->body) |
| 371 | { |
| 372 | obstack_free (scope->body, NULL); |
| 373 | xfree (scope->body); |
| 374 | } |
| 375 | VEC_pop (scope_level_s, parser->scopes); |
| 376 | } |
| 377 | |
| 378 | /* Wrapper for gdb_xml_end_element, to prevent throwing exceptions |
| 379 | through expat. */ |
| 380 | |
| 381 | static void |
| 382 | gdb_xml_end_element_wrapper (void *data, const XML_Char *name) |
| 383 | { |
| 384 | struct gdb_xml_parser *parser = data; |
| 385 | volatile struct gdb_exception ex; |
| 386 | |
| 387 | if (parser->error.reason < 0) |
| 388 | return; |
| 389 | |
| 390 | TRY_CATCH (ex, RETURN_MASK_ALL) |
| 391 | { |
| 392 | gdb_xml_end_element (data, name); |
| 393 | } |
| 394 | if (ex.reason < 0) |
| 395 | { |
| 396 | parser->error = ex; |
| 397 | #ifdef HAVE_XML_STOPPARSER |
| 398 | XML_StopParser (parser->expat_parser, XML_FALSE); |
| 399 | #endif |
| 400 | } |
| 401 | } |
| 402 | |
| 403 | /* Free a parser and all its associated state. */ |
| 404 | |
| 405 | static void |
| 406 | gdb_xml_cleanup (void *arg) |
| 407 | { |
| 408 | struct gdb_xml_parser *parser = arg; |
| 409 | struct scope_level *scope; |
| 410 | int ix; |
| 411 | |
| 412 | XML_ParserFree (parser->expat_parser); |
| 413 | |
| 414 | /* Clean up the scopes. */ |
| 415 | for (ix = 0; VEC_iterate (scope_level_s, parser->scopes, ix, scope); ix++) |
| 416 | if (scope->body) |
| 417 | { |
| 418 | obstack_free (scope->body, NULL); |
| 419 | xfree (scope->body); |
| 420 | } |
| 421 | VEC_free (scope_level_s, parser->scopes); |
| 422 | |
| 423 | xfree (parser); |
| 424 | } |
| 425 | |
| 426 | /* Initialize and return a parser. Register a cleanup to destroy the |
| 427 | parser. */ |
| 428 | |
| 429 | struct gdb_xml_parser * |
| 430 | gdb_xml_create_parser_and_cleanup (const char *name, |
| 431 | const struct gdb_xml_element *elements, |
| 432 | void *user_data) |
| 433 | { |
| 434 | struct gdb_xml_parser *parser; |
| 435 | struct scope_level start_scope; |
| 436 | |
| 437 | /* Initialize the parser. */ |
| 438 | parser = XZALLOC (struct gdb_xml_parser); |
| 439 | parser->expat_parser = XML_ParserCreateNS (NULL, '!'); |
| 440 | if (parser->expat_parser == NULL) |
| 441 | { |
| 442 | xfree (parser); |
| 443 | nomem (0); |
| 444 | } |
| 445 | |
| 446 | parser->name = name; |
| 447 | |
| 448 | parser->user_data = user_data; |
| 449 | XML_SetUserData (parser->expat_parser, parser); |
| 450 | |
| 451 | /* Set the callbacks. */ |
| 452 | XML_SetElementHandler (parser->expat_parser, gdb_xml_start_element_wrapper, |
| 453 | gdb_xml_end_element_wrapper); |
| 454 | XML_SetCharacterDataHandler (parser->expat_parser, gdb_xml_body_text); |
| 455 | |
| 456 | /* Initialize the outer scope. */ |
| 457 | memset (&start_scope, 0, sizeof (start_scope)); |
| 458 | start_scope.elements = elements; |
| 459 | VEC_safe_push (scope_level_s, parser->scopes, &start_scope); |
| 460 | |
| 461 | make_cleanup (gdb_xml_cleanup, parser); |
| 462 | |
| 463 | return parser; |
| 464 | } |
| 465 | |
| 466 | /* External entity handler. The only external entities we support |
| 467 | are those compiled into GDB (we do not fetch entities from the |
| 468 | target). */ |
| 469 | |
| 470 | static int XMLCALL |
| 471 | gdb_xml_fetch_external_entity (XML_Parser expat_parser, |
| 472 | const XML_Char *context, |
| 473 | const XML_Char *base, |
| 474 | const XML_Char *systemId, |
| 475 | const XML_Char *publicId) |
| 476 | { |
| 477 | struct gdb_xml_parser *parser = XML_GetUserData (expat_parser); |
| 478 | XML_Parser entity_parser; |
| 479 | const char *text; |
| 480 | enum XML_Status status; |
| 481 | |
| 482 | if (systemId == NULL) |
| 483 | { |
| 484 | text = fetch_xml_builtin (parser->dtd_name); |
| 485 | if (text == NULL) |
| 486 | internal_error (__FILE__, __LINE__, "could not locate built-in DTD %s", |
| 487 | parser->dtd_name); |
| 488 | } |
| 489 | else |
| 490 | { |
| 491 | text = fetch_xml_builtin (systemId); |
| 492 | if (text == NULL) |
| 493 | return XML_STATUS_ERROR; |
| 494 | } |
| 495 | |
| 496 | entity_parser = XML_ExternalEntityParserCreate (expat_parser, context, NULL); |
| 497 | |
| 498 | /* Don't use our handlers for the contents of the DTD. Just let expat |
| 499 | process it. */ |
| 500 | XML_SetElementHandler (entity_parser, NULL, NULL); |
| 501 | XML_SetDoctypeDeclHandler (entity_parser, NULL, NULL); |
| 502 | XML_SetXmlDeclHandler (entity_parser, NULL); |
| 503 | XML_SetDefaultHandler (entity_parser, NULL); |
| 504 | XML_SetUserData (entity_parser, NULL); |
| 505 | |
| 506 | status = XML_Parse (entity_parser, text, strlen (text), 1); |
| 507 | |
| 508 | XML_ParserFree (entity_parser); |
| 509 | return status; |
| 510 | } |
| 511 | |
| 512 | /* Associate DTD_NAME, which must be the name of a compiled-in DTD, |
| 513 | with PARSER. */ |
| 514 | |
| 515 | void |
| 516 | gdb_xml_use_dtd (struct gdb_xml_parser *parser, const char *dtd_name) |
| 517 | { |
| 518 | enum XML_Error err; |
| 519 | |
| 520 | parser->dtd_name = dtd_name; |
| 521 | |
| 522 | XML_SetParamEntityParsing (parser->expat_parser, |
| 523 | XML_PARAM_ENTITY_PARSING_UNLESS_STANDALONE); |
| 524 | XML_SetExternalEntityRefHandler (parser->expat_parser, |
| 525 | gdb_xml_fetch_external_entity); |
| 526 | |
| 527 | /* Even if no DTD is provided, use the built-in DTD anyway. */ |
| 528 | err = XML_UseForeignDTD (parser->expat_parser, XML_TRUE); |
| 529 | if (err != XML_ERROR_NONE) |
| 530 | internal_error (__FILE__, __LINE__, |
| 531 | "XML_UseForeignDTD failed: %s", XML_ErrorString (err)); |
| 532 | } |
| 533 | |
| 534 | /* Invoke PARSER on BUFFER. BUFFER is the data to parse, which |
| 535 | should be NUL-terminated. |
| 536 | |
| 537 | The return value is 0 for success or -1 for error. It may throw, |
| 538 | but only if something unexpected goes wrong during parsing; parse |
| 539 | errors will be caught, warned about, and reported as failure. */ |
| 540 | |
| 541 | int |
| 542 | gdb_xml_parse (struct gdb_xml_parser *parser, const char *buffer) |
| 543 | { |
| 544 | enum XML_Status status; |
| 545 | const char *error_string; |
| 546 | |
| 547 | gdb_xml_debug (parser, _("Starting:\n%s"), buffer); |
| 548 | |
| 549 | status = XML_Parse (parser->expat_parser, buffer, strlen (buffer), 1); |
| 550 | |
| 551 | if (status == XML_STATUS_OK && parser->error.reason == 0) |
| 552 | return 0; |
| 553 | |
| 554 | if (parser->error.reason == RETURN_ERROR |
| 555 | && parser->error.error == XML_PARSE_ERROR) |
| 556 | { |
| 557 | gdb_assert (parser->error.message != NULL); |
| 558 | error_string = parser->error.message; |
| 559 | } |
| 560 | else if (status == XML_STATUS_ERROR) |
| 561 | { |
| 562 | enum XML_Error err = XML_GetErrorCode (parser->expat_parser); |
| 563 | error_string = XML_ErrorString (err); |
| 564 | } |
| 565 | else |
| 566 | { |
| 567 | gdb_assert (parser->error.reason < 0); |
| 568 | throw_exception (parser->error); |
| 569 | } |
| 570 | |
| 571 | if (parser->last_line != 0) |
| 572 | warning (_("while parsing %s (at line %d): %s"), parser->name, |
| 573 | parser->last_line, error_string); |
| 574 | else |
| 575 | warning (_("while parsing %s: %s"), parser->name, error_string); |
| 576 | |
| 577 | return -1; |
| 578 | } |
| 579 | |
| 580 | /* Parse a field VALSTR that we expect to contain an integer value. |
| 581 | The integer is returned in *VALP. The string is parsed with an |
| 582 | equivalent to strtoul. |
| 583 | |
| 584 | Returns 0 for success, -1 for error. */ |
| 585 | |
| 586 | static int |
| 587 | xml_parse_unsigned_integer (const char *valstr, ULONGEST *valp) |
| 588 | { |
| 589 | const char *endptr; |
| 590 | ULONGEST result; |
| 591 | |
| 592 | if (*valstr == '\0') |
| 593 | return -1; |
| 594 | |
| 595 | result = strtoulst (valstr, &endptr, 0); |
| 596 | if (*endptr != '\0') |
| 597 | return -1; |
| 598 | |
| 599 | *valp = result; |
| 600 | return 0; |
| 601 | } |
| 602 | |
| 603 | /* Parse an integer string into a ULONGEST and return it, or call |
| 604 | gdb_xml_error if it could not be parsed. */ |
| 605 | |
| 606 | ULONGEST |
| 607 | gdb_xml_parse_ulongest (struct gdb_xml_parser *parser, const char *value) |
| 608 | { |
| 609 | ULONGEST result; |
| 610 | |
| 611 | if (xml_parse_unsigned_integer (value, &result) != 0) |
| 612 | gdb_xml_error (parser, _("Can't convert \"%s\" to an integer"), value); |
| 613 | |
| 614 | return result; |
| 615 | } |
| 616 | |
| 617 | /* Parse an integer attribute into a ULONGEST. */ |
| 618 | |
| 619 | void * |
| 620 | gdb_xml_parse_attr_ulongest (struct gdb_xml_parser *parser, |
| 621 | const struct gdb_xml_attribute *attribute, |
| 622 | const char *value) |
| 623 | { |
| 624 | ULONGEST result; |
| 625 | void *ret; |
| 626 | |
| 627 | if (xml_parse_unsigned_integer (value, &result) != 0) |
| 628 | gdb_xml_error (parser, _("Can't convert %s=\"%s\" to an integer"), |
| 629 | attribute->name, value); |
| 630 | |
| 631 | ret = xmalloc (sizeof (result)); |
| 632 | memcpy (ret, &result, sizeof (result)); |
| 633 | return ret; |
| 634 | } |
| 635 | |
| 636 | /* A handler_data for yes/no boolean values. */ |
| 637 | |
| 638 | const struct gdb_xml_enum gdb_xml_enums_boolean[] = { |
| 639 | { "yes", 1 }, |
| 640 | { "no", 0 }, |
| 641 | { NULL, 0 } |
| 642 | }; |
| 643 | |
| 644 | /* Map NAME to VALUE. A struct gdb_xml_enum * should be saved as the |
| 645 | value of handler_data when using gdb_xml_parse_attr_enum to parse a |
| 646 | fixed list of possible strings. The list is terminated by an entry |
| 647 | with NAME == NULL. */ |
| 648 | |
| 649 | void * |
| 650 | gdb_xml_parse_attr_enum (struct gdb_xml_parser *parser, |
| 651 | const struct gdb_xml_attribute *attribute, |
| 652 | const char *value) |
| 653 | { |
| 654 | const struct gdb_xml_enum *enums = attribute->handler_data; |
| 655 | void *ret; |
| 656 | |
| 657 | for (enums = attribute->handler_data; enums->name != NULL; enums++) |
| 658 | if (strcasecmp (enums->name, value) == 0) |
| 659 | break; |
| 660 | |
| 661 | if (enums->name == NULL) |
| 662 | gdb_xml_error (parser, _("Unknown attribute value %s=\"%s\""), |
| 663 | attribute->name, value); |
| 664 | |
| 665 | ret = xmalloc (sizeof (enums->value)); |
| 666 | memcpy (ret, &enums->value, sizeof (enums->value)); |
| 667 | return ret; |
| 668 | } |
| 669 | \f |
| 670 | |
| 671 | /* XInclude processing. This is done as a separate step from actually |
| 672 | parsing the document, so that we can produce a single combined XML |
| 673 | document - e.g. to hand to a front end or to simplify comparing two |
| 674 | documents. We make extensive use of XML_DefaultCurrent, to pass |
| 675 | input text directly into the output without reformatting or |
| 676 | requoting it. |
| 677 | |
| 678 | We output the DOCTYPE declaration for the first document unchanged, |
| 679 | if present, and discard DOCTYPEs from included documents. Only the |
| 680 | one we pass through here is used when we feed the result back to |
| 681 | expat. The XInclude standard explicitly does not discuss |
| 682 | validation of the result; we choose to apply the same DTD applied |
| 683 | to the outermost document. |
| 684 | |
| 685 | We can not simply include the external DTD subset in the document |
| 686 | as an internal subset, because <!IGNORE> and <!INCLUDE> are valid |
| 687 | only in external subsets. But if we do not pass the DTD into the |
| 688 | output at all, default values will not be filled in. |
| 689 | |
| 690 | We don't pass through any <?xml> declaration because we generate |
| 691 | UTF-8, not whatever the input encoding was. */ |
| 692 | |
| 693 | struct xinclude_parsing_data |
| 694 | { |
| 695 | /* The obstack to build the output in. */ |
| 696 | struct obstack obstack; |
| 697 | |
| 698 | /* A count indicating whether we are in an element whose |
| 699 | children should not be copied to the output, and if so, |
| 700 | how deep we are nested. This is used for anything inside |
| 701 | an xi:include, and for the DTD. */ |
| 702 | int skip_depth; |
| 703 | |
| 704 | /* The number of <xi:include> elements currently being processed, |
| 705 | to detect loops. */ |
| 706 | int include_depth; |
| 707 | |
| 708 | /* A function to call to obtain additional features, and its |
| 709 | baton. */ |
| 710 | xml_fetch_another fetcher; |
| 711 | void *fetcher_baton; |
| 712 | }; |
| 713 | |
| 714 | static void |
| 715 | xinclude_start_include (struct gdb_xml_parser *parser, |
| 716 | const struct gdb_xml_element *element, |
| 717 | void *user_data, VEC(gdb_xml_value_s) *attributes) |
| 718 | { |
| 719 | struct xinclude_parsing_data *data = user_data; |
| 720 | char *href = VEC_index (gdb_xml_value_s, attributes, 0)->value; |
| 721 | struct cleanup *back_to; |
| 722 | char *text, *output; |
| 723 | int ret; |
| 724 | |
| 725 | gdb_xml_debug (parser, _("Processing XInclude of \"%s\""), href); |
| 726 | |
| 727 | if (data->include_depth > MAX_XINCLUDE_DEPTH) |
| 728 | gdb_xml_error (parser, _("Maximum XInclude depth (%d) exceeded"), |
| 729 | MAX_XINCLUDE_DEPTH); |
| 730 | |
| 731 | text = data->fetcher (href, data->fetcher_baton); |
| 732 | if (text == NULL) |
| 733 | gdb_xml_error (parser, _("Could not load XML document \"%s\""), href); |
| 734 | back_to = make_cleanup (xfree, text); |
| 735 | |
| 736 | output = xml_process_xincludes (parser->name, text, data->fetcher, |
| 737 | data->fetcher_baton, |
| 738 | data->include_depth + 1); |
| 739 | if (output == NULL) |
| 740 | gdb_xml_error (parser, _("Parsing \"%s\" failed"), href); |
| 741 | |
| 742 | obstack_grow (&data->obstack, output, strlen (output)); |
| 743 | xfree (output); |
| 744 | |
| 745 | do_cleanups (back_to); |
| 746 | |
| 747 | data->skip_depth++; |
| 748 | } |
| 749 | |
| 750 | static void |
| 751 | xinclude_end_include (struct gdb_xml_parser *parser, |
| 752 | const struct gdb_xml_element *element, |
| 753 | void *user_data, const char *body_text) |
| 754 | { |
| 755 | struct xinclude_parsing_data *data = user_data; |
| 756 | |
| 757 | data->skip_depth--; |
| 758 | } |
| 759 | |
| 760 | static void XMLCALL |
| 761 | xml_xinclude_default (void *data_, const XML_Char *s, int len) |
| 762 | { |
| 763 | struct gdb_xml_parser *parser = data_; |
| 764 | struct xinclude_parsing_data *data = parser->user_data; |
| 765 | |
| 766 | /* If we are inside of e.g. xi:include or the DTD, don't save this |
| 767 | string. */ |
| 768 | if (data->skip_depth) |
| 769 | return; |
| 770 | |
| 771 | /* Otherwise just add it to the end of the document we're building |
| 772 | up. */ |
| 773 | obstack_grow (&data->obstack, s, len); |
| 774 | } |
| 775 | |
| 776 | static void XMLCALL |
| 777 | xml_xinclude_start_doctype (void *data_, const XML_Char *doctypeName, |
| 778 | const XML_Char *sysid, const XML_Char *pubid, |
| 779 | int has_internal_subset) |
| 780 | { |
| 781 | struct gdb_xml_parser *parser = data_; |
| 782 | struct xinclude_parsing_data *data = parser->user_data; |
| 783 | |
| 784 | /* Don't print out the doctype, or the contents of the DTD internal |
| 785 | subset, if any. */ |
| 786 | data->skip_depth++; |
| 787 | } |
| 788 | |
| 789 | static void XMLCALL |
| 790 | xml_xinclude_end_doctype (void *data_) |
| 791 | { |
| 792 | struct gdb_xml_parser *parser = data_; |
| 793 | struct xinclude_parsing_data *data = parser->user_data; |
| 794 | |
| 795 | data->skip_depth--; |
| 796 | } |
| 797 | |
| 798 | static void XMLCALL |
| 799 | xml_xinclude_xml_decl (void *data_, const XML_Char *version, |
| 800 | const XML_Char *encoding, int standalone) |
| 801 | { |
| 802 | /* Do nothing - this function prevents the default handler from |
| 803 | being called, thus suppressing the XML declaration from the |
| 804 | output. */ |
| 805 | } |
| 806 | |
| 807 | static void |
| 808 | xml_xinclude_cleanup (void *data_) |
| 809 | { |
| 810 | struct xinclude_parsing_data *data = data_; |
| 811 | |
| 812 | obstack_free (&data->obstack, NULL); |
| 813 | xfree (data); |
| 814 | } |
| 815 | |
| 816 | const struct gdb_xml_attribute xinclude_attributes[] = { |
| 817 | { "href", GDB_XML_AF_NONE, NULL, NULL }, |
| 818 | { NULL, GDB_XML_AF_NONE, NULL, NULL } |
| 819 | }; |
| 820 | |
| 821 | const struct gdb_xml_element xinclude_elements[] = { |
| 822 | { "http://www.w3.org/2001/XInclude!include", xinclude_attributes, NULL, |
| 823 | GDB_XML_EF_OPTIONAL | GDB_XML_EF_REPEATABLE, |
| 824 | xinclude_start_include, xinclude_end_include }, |
| 825 | { NULL, NULL, NULL, GDB_XML_EF_NONE, NULL, NULL } |
| 826 | }; |
| 827 | |
| 828 | /* The main entry point for <xi:include> processing. */ |
| 829 | |
| 830 | char * |
| 831 | xml_process_xincludes (const char *name, const char *text, |
| 832 | xml_fetch_another fetcher, void *fetcher_baton, |
| 833 | int depth) |
| 834 | { |
| 835 | enum XML_Error err; |
| 836 | struct gdb_xml_parser *parser; |
| 837 | struct xinclude_parsing_data *data; |
| 838 | struct cleanup *back_to; |
| 839 | char *result = NULL; |
| 840 | |
| 841 | data = XZALLOC (struct xinclude_parsing_data); |
| 842 | obstack_init (&data->obstack); |
| 843 | back_to = make_cleanup (xml_xinclude_cleanup, data); |
| 844 | |
| 845 | parser = gdb_xml_create_parser_and_cleanup (name, xinclude_elements, data); |
| 846 | parser->is_xinclude = 1; |
| 847 | |
| 848 | data->include_depth = depth; |
| 849 | data->fetcher = fetcher; |
| 850 | data->fetcher_baton = fetcher_baton; |
| 851 | |
| 852 | XML_SetCharacterDataHandler (parser->expat_parser, NULL); |
| 853 | XML_SetDefaultHandler (parser->expat_parser, xml_xinclude_default); |
| 854 | |
| 855 | /* Always discard the XML version declarations; the only important |
| 856 | thing this provides is encoding, and our result will have been |
| 857 | converted to UTF-8. */ |
| 858 | XML_SetXmlDeclHandler (parser->expat_parser, xml_xinclude_xml_decl); |
| 859 | |
| 860 | if (depth > 0) |
| 861 | /* Discard the doctype for included documents. */ |
| 862 | XML_SetDoctypeDeclHandler (parser->expat_parser, |
| 863 | xml_xinclude_start_doctype, |
| 864 | xml_xinclude_end_doctype); |
| 865 | |
| 866 | gdb_xml_use_dtd (parser, "xinclude.dtd"); |
| 867 | |
| 868 | if (gdb_xml_parse (parser, text) == 0) |
| 869 | { |
| 870 | obstack_1grow (&data->obstack, '\0'); |
| 871 | result = xstrdup (obstack_finish (&data->obstack)); |
| 872 | |
| 873 | if (depth == 0) |
| 874 | gdb_xml_debug (parser, _("XInclude processing succeeded.")); |
| 875 | } |
| 876 | else |
| 877 | result = NULL; |
| 878 | |
| 879 | do_cleanups (back_to); |
| 880 | return result; |
| 881 | } |
| 882 | #endif /* HAVE_LIBEXPAT */ |
| 883 | \f |
| 884 | |
| 885 | /* Return an XML document which was compiled into GDB, from |
| 886 | the given FILENAME, or NULL if the file was not compiled in. */ |
| 887 | |
| 888 | const char * |
| 889 | fetch_xml_builtin (const char *filename) |
| 890 | { |
| 891 | const char *(*p)[2]; |
| 892 | |
| 893 | for (p = xml_builtin; (*p)[0]; p++) |
| 894 | if (strcmp ((*p)[0], filename) == 0) |
| 895 | return (*p)[1]; |
| 896 | |
| 897 | return NULL; |
| 898 | } |
| 899 | |
| 900 | /* A to_xfer_partial helper function which reads XML files which were |
| 901 | compiled into GDB. The target may call this function from its own |
| 902 | to_xfer_partial handler, after converting object and annex to the |
| 903 | appropriate filename. */ |
| 904 | |
| 905 | LONGEST |
| 906 | xml_builtin_xfer_partial (const char *filename, |
| 907 | gdb_byte *readbuf, const gdb_byte *writebuf, |
| 908 | ULONGEST offset, LONGEST len) |
| 909 | { |
| 910 | const char *buf; |
| 911 | LONGEST len_avail; |
| 912 | |
| 913 | gdb_assert (readbuf != NULL && writebuf == NULL); |
| 914 | gdb_assert (filename != NULL); |
| 915 | |
| 916 | buf = fetch_xml_builtin (filename); |
| 917 | if (buf == NULL) |
| 918 | return -1; |
| 919 | |
| 920 | len_avail = strlen (buf); |
| 921 | if (offset >= len_avail) |
| 922 | return 0; |
| 923 | |
| 924 | if (len > len_avail - offset) |
| 925 | len = len_avail - offset; |
| 926 | memcpy (readbuf, buf + offset, len); |
| 927 | return len; |
| 928 | } |
| 929 | \f |
| 930 | |
| 931 | static void |
| 932 | show_debug_xml (struct ui_file *file, int from_tty, |
| 933 | struct cmd_list_element *c, const char *value) |
| 934 | { |
| 935 | fprintf_filtered (file, _("XML debugging is %s.\n"), value); |
| 936 | } |
| 937 | |
| 938 | /* Return a malloc allocated string with special characters from TEXT |
| 939 | replaced by entity references. */ |
| 940 | |
| 941 | char * |
| 942 | xml_escape_text (const char *text) |
| 943 | { |
| 944 | char *result; |
| 945 | int i, special; |
| 946 | |
| 947 | /* Compute the length of the result. */ |
| 948 | for (i = 0, special = 0; text[i] != '\0'; i++) |
| 949 | switch (text[i]) |
| 950 | { |
| 951 | case '\'': |
| 952 | case '\"': |
| 953 | special += 5; |
| 954 | break; |
| 955 | case '&': |
| 956 | special += 4; |
| 957 | break; |
| 958 | case '<': |
| 959 | case '>': |
| 960 | special += 3; |
| 961 | break; |
| 962 | default: |
| 963 | break; |
| 964 | } |
| 965 | |
| 966 | /* Expand the result. */ |
| 967 | result = xmalloc (i + special + 1); |
| 968 | for (i = 0, special = 0; text[i] != '\0'; i++) |
| 969 | switch (text[i]) |
| 970 | { |
| 971 | case '\'': |
| 972 | strcpy (result + i + special, "'"); |
| 973 | special += 5; |
| 974 | break; |
| 975 | case '\"': |
| 976 | strcpy (result + i + special, """); |
| 977 | special += 5; |
| 978 | break; |
| 979 | case '&': |
| 980 | strcpy (result + i + special, "&"); |
| 981 | special += 4; |
| 982 | break; |
| 983 | case '<': |
| 984 | strcpy (result + i + special, "<"); |
| 985 | special += 3; |
| 986 | break; |
| 987 | case '>': |
| 988 | strcpy (result + i + special, ">"); |
| 989 | special += 3; |
| 990 | break; |
| 991 | default: |
| 992 | result[i + special] = text[i]; |
| 993 | break; |
| 994 | } |
| 995 | result[i + special] = '\0'; |
| 996 | |
| 997 | return result; |
| 998 | } |
| 999 | |
| 1000 | void |
| 1001 | obstack_xml_printf (struct obstack *obstack, const char *format, ...) |
| 1002 | { |
| 1003 | va_list ap; |
| 1004 | const char *f; |
| 1005 | const char *prev; |
| 1006 | int percent = 0; |
| 1007 | |
| 1008 | va_start (ap, format); |
| 1009 | |
| 1010 | prev = format; |
| 1011 | for (f = format; *f; f++) |
| 1012 | { |
| 1013 | if (percent) |
| 1014 | { |
| 1015 | switch (*f) |
| 1016 | { |
| 1017 | case 's': |
| 1018 | { |
| 1019 | char *p; |
| 1020 | char *a = va_arg (ap, char *); |
| 1021 | obstack_grow (obstack, prev, f - prev - 1); |
| 1022 | p = xml_escape_text (a); |
| 1023 | obstack_grow_str (obstack, p); |
| 1024 | xfree (p); |
| 1025 | prev = f + 1; |
| 1026 | } |
| 1027 | break; |
| 1028 | } |
| 1029 | percent = 0; |
| 1030 | } |
| 1031 | else if (*f == '%') |
| 1032 | percent = 1; |
| 1033 | } |
| 1034 | |
| 1035 | obstack_grow_str (obstack, prev); |
| 1036 | va_end (ap); |
| 1037 | } |
| 1038 | |
| 1039 | void _initialize_xml_support (void); |
| 1040 | |
| 1041 | void |
| 1042 | _initialize_xml_support (void) |
| 1043 | { |
| 1044 | add_setshow_boolean_cmd ("xml", class_maintenance, &debug_xml, |
| 1045 | _("Set XML parser debugging."), |
| 1046 | _("Show XML parser debugging."), |
| 1047 | _("When set, debugging messages for XML parsers " |
| 1048 | "are displayed."), |
| 1049 | NULL, show_debug_xml, |
| 1050 | &setdebuglist, &showdebuglist); |
| 1051 | } |