| 1 | /* varobj support for Ada. |
| 2 | |
| 3 | Copyright (C) 2012-2017 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 "ada-lang.h" |
| 22 | #include "varobj.h" |
| 23 | #include "language.h" |
| 24 | #include "valprint.h" |
| 25 | |
| 26 | /* Implementation principle used in this unit: |
| 27 | |
| 28 | For our purposes, the meat of the varobj object is made of two |
| 29 | elements: The varobj's (struct) value, and the varobj's (struct) |
| 30 | type. In most situations, the varobj has a non-NULL value, and |
| 31 | the type becomes redundant, as it can be directly derived from |
| 32 | the value. In the initial implementation of this unit, most |
| 33 | routines would only take a value, and return a value. |
| 34 | |
| 35 | But there are many situations where it is possible for a varobj |
| 36 | to have a NULL value. For instance, if the varobj becomes out of |
| 37 | scope. Or better yet, when the varobj is the child of another |
| 38 | NULL pointer varobj. In that situation, we must rely on the type |
| 39 | instead of the value to create the child varobj. |
| 40 | |
| 41 | That's why most functions below work with a (value, type) pair. |
| 42 | The value may or may not be NULL. But the type is always expected |
| 43 | to be set. When the value is NULL, then we work with the type |
| 44 | alone, and keep the value NULL. But when the value is not NULL, |
| 45 | then we work using the value, because it provides more information. |
| 46 | But we still always set the type as well, even if that type could |
| 47 | easily be derived from the value. The reason behind this is that |
| 48 | it allows the code to use the type without having to worry about |
| 49 | it being set or not. It makes the code clearer. */ |
| 50 | |
| 51 | static int ada_varobj_get_number_of_children (struct value *parent_value, |
| 52 | struct type *parent_type); |
| 53 | |
| 54 | /* A convenience function that decodes the VALUE_PTR/TYPE_PTR couple: |
| 55 | If there is a value (*VALUE_PTR not NULL), then perform the decoding |
| 56 | using it, and compute the associated type from the resulting value. |
| 57 | Otherwise, compute a static approximation of *TYPE_PTR, leaving |
| 58 | *VALUE_PTR unchanged. |
| 59 | |
| 60 | The results are written in place. */ |
| 61 | |
| 62 | static void |
| 63 | ada_varobj_decode_var (struct value **value_ptr, struct type **type_ptr) |
| 64 | { |
| 65 | if (*value_ptr) |
| 66 | { |
| 67 | *value_ptr = ada_get_decoded_value (*value_ptr); |
| 68 | *type_ptr = ada_check_typedef (value_type (*value_ptr)); |
| 69 | } |
| 70 | else |
| 71 | *type_ptr = ada_get_decoded_type (*type_ptr); |
| 72 | } |
| 73 | |
| 74 | /* Return a string containing an image of the given scalar value. |
| 75 | VAL is the numeric value, while TYPE is the value's type. |
| 76 | This is useful for plain integers, of course, but even more |
| 77 | so for enumerated types. */ |
| 78 | |
| 79 | static std::string |
| 80 | ada_varobj_scalar_image (struct type *type, LONGEST val) |
| 81 | { |
| 82 | string_file buf; |
| 83 | |
| 84 | ada_print_scalar (type, val, &buf); |
| 85 | return std::move (buf.string ()); |
| 86 | } |
| 87 | |
| 88 | /* Assuming that the (PARENT_VALUE, PARENT_TYPE) pair designates |
| 89 | a struct or union, compute the (CHILD_VALUE, CHILD_TYPE) couple |
| 90 | corresponding to the field number FIELDNO. */ |
| 91 | |
| 92 | static void |
| 93 | ada_varobj_struct_elt (struct value *parent_value, |
| 94 | struct type *parent_type, |
| 95 | int fieldno, |
| 96 | struct value **child_value, |
| 97 | struct type **child_type) |
| 98 | { |
| 99 | struct value *value = NULL; |
| 100 | struct type *type = NULL; |
| 101 | |
| 102 | if (parent_value) |
| 103 | { |
| 104 | value = value_field (parent_value, fieldno); |
| 105 | type = value_type (value); |
| 106 | } |
| 107 | else |
| 108 | type = TYPE_FIELD_TYPE (parent_type, fieldno); |
| 109 | |
| 110 | if (child_value) |
| 111 | *child_value = value; |
| 112 | if (child_type) |
| 113 | *child_type = type; |
| 114 | } |
| 115 | |
| 116 | /* Assuming that the (PARENT_VALUE, PARENT_TYPE) pair is a pointer or |
| 117 | reference, return a (CHILD_VALUE, CHILD_TYPE) couple corresponding |
| 118 | to the dereferenced value. */ |
| 119 | |
| 120 | static void |
| 121 | ada_varobj_ind (struct value *parent_value, |
| 122 | struct type *parent_type, |
| 123 | struct value **child_value, |
| 124 | struct type **child_type) |
| 125 | { |
| 126 | struct value *value = NULL; |
| 127 | struct type *type = NULL; |
| 128 | |
| 129 | if (ada_is_array_descriptor_type (parent_type)) |
| 130 | { |
| 131 | /* This can only happen when PARENT_VALUE is NULL. Otherwise, |
| 132 | ada_get_decoded_value would have transformed our parent_type |
| 133 | into a simple array pointer type. */ |
| 134 | gdb_assert (parent_value == NULL); |
| 135 | gdb_assert (TYPE_CODE (parent_type) == TYPE_CODE_TYPEDEF); |
| 136 | |
| 137 | /* Decode parent_type by the equivalent pointer to (decoded) |
| 138 | array. */ |
| 139 | while (TYPE_CODE (parent_type) == TYPE_CODE_TYPEDEF) |
| 140 | parent_type = TYPE_TARGET_TYPE (parent_type); |
| 141 | parent_type = ada_coerce_to_simple_array_type (parent_type); |
| 142 | parent_type = lookup_pointer_type (parent_type); |
| 143 | } |
| 144 | |
| 145 | /* If parent_value is a null pointer, then only perform static |
| 146 | dereferencing. We cannot dereference null pointers. */ |
| 147 | if (parent_value && value_as_address (parent_value) == 0) |
| 148 | parent_value = NULL; |
| 149 | |
| 150 | if (parent_value) |
| 151 | { |
| 152 | value = ada_value_ind (parent_value); |
| 153 | type = value_type (value); |
| 154 | } |
| 155 | else |
| 156 | type = TYPE_TARGET_TYPE (parent_type); |
| 157 | |
| 158 | if (child_value) |
| 159 | *child_value = value; |
| 160 | if (child_type) |
| 161 | *child_type = type; |
| 162 | } |
| 163 | |
| 164 | /* Assuming that the (PARENT_VALUE, PARENT_TYPE) pair is a simple |
| 165 | array (TYPE_CODE_ARRAY), return the (CHILD_VALUE, CHILD_TYPE) |
| 166 | pair corresponding to the element at ELT_INDEX. */ |
| 167 | |
| 168 | static void |
| 169 | ada_varobj_simple_array_elt (struct value *parent_value, |
| 170 | struct type *parent_type, |
| 171 | int elt_index, |
| 172 | struct value **child_value, |
| 173 | struct type **child_type) |
| 174 | { |
| 175 | struct value *value = NULL; |
| 176 | struct type *type = NULL; |
| 177 | |
| 178 | if (parent_value) |
| 179 | { |
| 180 | struct value *index_value = |
| 181 | value_from_longest (TYPE_INDEX_TYPE (parent_type), elt_index); |
| 182 | |
| 183 | value = ada_value_subscript (parent_value, 1, &index_value); |
| 184 | type = value_type (value); |
| 185 | } |
| 186 | else |
| 187 | type = TYPE_TARGET_TYPE (parent_type); |
| 188 | |
| 189 | if (child_value) |
| 190 | *child_value = value; |
| 191 | if (child_type) |
| 192 | *child_type = type; |
| 193 | } |
| 194 | |
| 195 | /* Given the decoded value and decoded type of a variable object, |
| 196 | adjust the value and type to those necessary for getting children |
| 197 | of the variable object. |
| 198 | |
| 199 | The replacement is performed in place. */ |
| 200 | |
| 201 | static void |
| 202 | ada_varobj_adjust_for_child_access (struct value **value, |
| 203 | struct type **type) |
| 204 | { |
| 205 | /* Pointers to struct/union types are special: Instead of having |
| 206 | one child (the struct), their children are the components of |
| 207 | the struct/union type. We handle this situation by dereferencing |
| 208 | the (value, type) couple. */ |
| 209 | if (TYPE_CODE (*type) == TYPE_CODE_PTR |
| 210 | && (TYPE_CODE (TYPE_TARGET_TYPE (*type)) == TYPE_CODE_STRUCT |
| 211 | || TYPE_CODE (TYPE_TARGET_TYPE (*type)) == TYPE_CODE_UNION) |
| 212 | && !ada_is_array_descriptor_type (TYPE_TARGET_TYPE (*type)) |
| 213 | && !ada_is_constrained_packed_array_type (TYPE_TARGET_TYPE (*type))) |
| 214 | ada_varobj_ind (*value, *type, value, type); |
| 215 | |
| 216 | /* If this is a tagged type, we need to transform it a bit in order |
| 217 | to be able to fetch its full view. As always with tagged types, |
| 218 | we can only do that if we have a value. */ |
| 219 | if (*value != NULL && ada_is_tagged_type (*type, 1)) |
| 220 | { |
| 221 | *value = ada_tag_value_at_base_address (*value); |
| 222 | *type = value_type (*value); |
| 223 | } |
| 224 | } |
| 225 | |
| 226 | /* Assuming that the (PARENT_VALUE, PARENT_TYPE) pair is an array |
| 227 | (any type of array, "simple" or not), return the number of children |
| 228 | that this array contains. */ |
| 229 | |
| 230 | static int |
| 231 | ada_varobj_get_array_number_of_children (struct value *parent_value, |
| 232 | struct type *parent_type) |
| 233 | { |
| 234 | LONGEST lo, hi; |
| 235 | |
| 236 | if (parent_value == NULL |
| 237 | && is_dynamic_type (TYPE_INDEX_TYPE (parent_type))) |
| 238 | { |
| 239 | /* This happens when listing the children of an object |
| 240 | which does not exist in memory (Eg: when requesting |
| 241 | the children of a null pointer, which is allowed by |
| 242 | varobj). The array index type being dynamic, we cannot |
| 243 | determine how many elements this array has. Just assume |
| 244 | it has none. */ |
| 245 | return 0; |
| 246 | } |
| 247 | |
| 248 | if (!get_array_bounds (parent_type, &lo, &hi)) |
| 249 | { |
| 250 | /* Could not get the array bounds. Pretend this is an empty array. */ |
| 251 | warning (_("unable to get bounds of array, assuming null array")); |
| 252 | return 0; |
| 253 | } |
| 254 | |
| 255 | /* Ada allows the upper bound to be less than the lower bound, |
| 256 | in order to specify empty arrays... */ |
| 257 | if (hi < lo) |
| 258 | return 0; |
| 259 | |
| 260 | return hi - lo + 1; |
| 261 | } |
| 262 | |
| 263 | /* Assuming that the (PARENT_VALUE, PARENT_TYPE) pair is a struct or |
| 264 | union, return the number of children this struct contains. */ |
| 265 | |
| 266 | static int |
| 267 | ada_varobj_get_struct_number_of_children (struct value *parent_value, |
| 268 | struct type *parent_type) |
| 269 | { |
| 270 | int n_children = 0; |
| 271 | int i; |
| 272 | |
| 273 | gdb_assert (TYPE_CODE (parent_type) == TYPE_CODE_STRUCT |
| 274 | || TYPE_CODE (parent_type) == TYPE_CODE_UNION); |
| 275 | |
| 276 | for (i = 0; i < TYPE_NFIELDS (parent_type); i++) |
| 277 | { |
| 278 | if (ada_is_ignored_field (parent_type, i)) |
| 279 | continue; |
| 280 | |
| 281 | if (ada_is_wrapper_field (parent_type, i)) |
| 282 | { |
| 283 | struct value *elt_value; |
| 284 | struct type *elt_type; |
| 285 | |
| 286 | ada_varobj_struct_elt (parent_value, parent_type, i, |
| 287 | &elt_value, &elt_type); |
| 288 | if (ada_is_tagged_type (elt_type, 0)) |
| 289 | { |
| 290 | /* We must not use ada_varobj_get_number_of_children |
| 291 | to determine is element's number of children, because |
| 292 | this function first calls ada_varobj_decode_var, |
| 293 | which "fixes" the element. For tagged types, this |
| 294 | includes reading the object's tag to determine its |
| 295 | real type, which happens to be the parent_type, and |
| 296 | leads to an infinite loop (because the element gets |
| 297 | fixed back into the parent). */ |
| 298 | n_children += ada_varobj_get_struct_number_of_children |
| 299 | (elt_value, elt_type); |
| 300 | } |
| 301 | else |
| 302 | n_children += ada_varobj_get_number_of_children (elt_value, elt_type); |
| 303 | } |
| 304 | else if (ada_is_variant_part (parent_type, i)) |
| 305 | { |
| 306 | /* In normal situations, the variant part of the record should |
| 307 | have been "fixed". Or, in other words, it should have been |
| 308 | replaced by the branch of the variant part that is relevant |
| 309 | for our value. But there are still situations where this |
| 310 | can happen, however (Eg. when our parent is a NULL pointer). |
| 311 | We do not support showing this part of the record for now, |
| 312 | so just pretend this field does not exist. */ |
| 313 | } |
| 314 | else |
| 315 | n_children++; |
| 316 | } |
| 317 | |
| 318 | return n_children; |
| 319 | } |
| 320 | |
| 321 | /* Assuming that the (PARENT_VALUE, PARENT_TYPE) pair designates |
| 322 | a pointer, return the number of children this pointer has. */ |
| 323 | |
| 324 | static int |
| 325 | ada_varobj_get_ptr_number_of_children (struct value *parent_value, |
| 326 | struct type *parent_type) |
| 327 | { |
| 328 | struct type *child_type = TYPE_TARGET_TYPE (parent_type); |
| 329 | |
| 330 | /* Pointer to functions and to void do not have a child, since |
| 331 | you cannot print what they point to. */ |
| 332 | if (TYPE_CODE (child_type) == TYPE_CODE_FUNC |
| 333 | || TYPE_CODE (child_type) == TYPE_CODE_VOID) |
| 334 | return 0; |
| 335 | |
| 336 | /* All other types have 1 child. */ |
| 337 | return 1; |
| 338 | } |
| 339 | |
| 340 | /* Return the number of children for the (PARENT_VALUE, PARENT_TYPE) |
| 341 | pair. */ |
| 342 | |
| 343 | static int |
| 344 | ada_varobj_get_number_of_children (struct value *parent_value, |
| 345 | struct type *parent_type) |
| 346 | { |
| 347 | ada_varobj_decode_var (&parent_value, &parent_type); |
| 348 | ada_varobj_adjust_for_child_access (&parent_value, &parent_type); |
| 349 | |
| 350 | /* A typedef to an array descriptor in fact represents a pointer |
| 351 | to an unconstrained array. These types always have one child |
| 352 | (the unconstrained array). */ |
| 353 | if (ada_is_array_descriptor_type (parent_type) |
| 354 | && TYPE_CODE (parent_type) == TYPE_CODE_TYPEDEF) |
| 355 | return 1; |
| 356 | |
| 357 | if (TYPE_CODE (parent_type) == TYPE_CODE_ARRAY) |
| 358 | return ada_varobj_get_array_number_of_children (parent_value, |
| 359 | parent_type); |
| 360 | |
| 361 | if (TYPE_CODE (parent_type) == TYPE_CODE_STRUCT |
| 362 | || TYPE_CODE (parent_type) == TYPE_CODE_UNION) |
| 363 | return ada_varobj_get_struct_number_of_children (parent_value, |
| 364 | parent_type); |
| 365 | |
| 366 | if (TYPE_CODE (parent_type) == TYPE_CODE_PTR) |
| 367 | return ada_varobj_get_ptr_number_of_children (parent_value, |
| 368 | parent_type); |
| 369 | |
| 370 | /* All other types have no child. */ |
| 371 | return 0; |
| 372 | } |
| 373 | |
| 374 | /* Describe the child of the (PARENT_VALUE, PARENT_TYPE) pair |
| 375 | whose index is CHILD_INDEX: |
| 376 | |
| 377 | - If CHILD_NAME is not NULL, then a copy of the child's name |
| 378 | is saved in *CHILD_NAME. This copy must be deallocated |
| 379 | with xfree after use. |
| 380 | |
| 381 | - If CHILD_VALUE is not NULL, then save the child's value |
| 382 | in *CHILD_VALUE. Same thing for the child's type with |
| 383 | CHILD_TYPE if not NULL. |
| 384 | |
| 385 | - If CHILD_PATH_EXPR is not NULL, then compute the child's |
| 386 | path expression. The resulting string must be deallocated |
| 387 | after use with xfree. |
| 388 | |
| 389 | Computing the child's path expression requires the PARENT_PATH_EXPR |
| 390 | to be non-NULL. Otherwise, PARENT_PATH_EXPR may be null if |
| 391 | CHILD_PATH_EXPR is NULL. |
| 392 | |
| 393 | PARENT_NAME is the name of the parent, and should never be NULL. */ |
| 394 | |
| 395 | static void ada_varobj_describe_child (struct value *parent_value, |
| 396 | struct type *parent_type, |
| 397 | const char *parent_name, |
| 398 | const char *parent_path_expr, |
| 399 | int child_index, |
| 400 | std::string *child_name, |
| 401 | struct value **child_value, |
| 402 | struct type **child_type, |
| 403 | std::string *child_path_expr); |
| 404 | |
| 405 | /* Same as ada_varobj_describe_child, but limited to struct/union |
| 406 | objects. */ |
| 407 | |
| 408 | static void |
| 409 | ada_varobj_describe_struct_child (struct value *parent_value, |
| 410 | struct type *parent_type, |
| 411 | const char *parent_name, |
| 412 | const char *parent_path_expr, |
| 413 | int child_index, |
| 414 | std::string *child_name, |
| 415 | struct value **child_value, |
| 416 | struct type **child_type, |
| 417 | std::string *child_path_expr) |
| 418 | { |
| 419 | int fieldno; |
| 420 | int childno = 0; |
| 421 | |
| 422 | gdb_assert (TYPE_CODE (parent_type) == TYPE_CODE_STRUCT); |
| 423 | |
| 424 | for (fieldno = 0; fieldno < TYPE_NFIELDS (parent_type); fieldno++) |
| 425 | { |
| 426 | if (ada_is_ignored_field (parent_type, fieldno)) |
| 427 | continue; |
| 428 | |
| 429 | if (ada_is_wrapper_field (parent_type, fieldno)) |
| 430 | { |
| 431 | struct value *elt_value; |
| 432 | struct type *elt_type; |
| 433 | int elt_n_children; |
| 434 | |
| 435 | ada_varobj_struct_elt (parent_value, parent_type, fieldno, |
| 436 | &elt_value, &elt_type); |
| 437 | if (ada_is_tagged_type (elt_type, 0)) |
| 438 | { |
| 439 | /* Same as in ada_varobj_get_struct_number_of_children: |
| 440 | For tagged types, we must be careful to not call |
| 441 | ada_varobj_get_number_of_children, to prevent our |
| 442 | element from being fixed back into the parent. */ |
| 443 | elt_n_children = ada_varobj_get_struct_number_of_children |
| 444 | (elt_value, elt_type); |
| 445 | } |
| 446 | else |
| 447 | elt_n_children = |
| 448 | ada_varobj_get_number_of_children (elt_value, elt_type); |
| 449 | |
| 450 | /* Is the child we're looking for one of the children |
| 451 | of this wrapper field? */ |
| 452 | if (child_index - childno < elt_n_children) |
| 453 | { |
| 454 | if (ada_is_tagged_type (elt_type, 0)) |
| 455 | { |
| 456 | /* Same as in ada_varobj_get_struct_number_of_children: |
| 457 | For tagged types, we must be careful to not call |
| 458 | ada_varobj_describe_child, to prevent our element |
| 459 | from being fixed back into the parent. */ |
| 460 | ada_varobj_describe_struct_child |
| 461 | (elt_value, elt_type, parent_name, parent_path_expr, |
| 462 | child_index - childno, child_name, child_value, |
| 463 | child_type, child_path_expr); |
| 464 | } |
| 465 | else |
| 466 | ada_varobj_describe_child (elt_value, elt_type, |
| 467 | parent_name, parent_path_expr, |
| 468 | child_index - childno, |
| 469 | child_name, child_value, |
| 470 | child_type, child_path_expr); |
| 471 | return; |
| 472 | } |
| 473 | |
| 474 | /* The child we're looking for is beyond this wrapper |
| 475 | field, so skip all its children. */ |
| 476 | childno += elt_n_children; |
| 477 | continue; |
| 478 | } |
| 479 | else if (ada_is_variant_part (parent_type, fieldno)) |
| 480 | { |
| 481 | /* In normal situations, the variant part of the record should |
| 482 | have been "fixed". Or, in other words, it should have been |
| 483 | replaced by the branch of the variant part that is relevant |
| 484 | for our value. But there are still situations where this |
| 485 | can happen, however (Eg. when our parent is a NULL pointer). |
| 486 | We do not support showing this part of the record for now, |
| 487 | so just pretend this field does not exist. */ |
| 488 | continue; |
| 489 | } |
| 490 | |
| 491 | if (childno == child_index) |
| 492 | { |
| 493 | if (child_name) |
| 494 | { |
| 495 | /* The name of the child is none other than the field's |
| 496 | name, except that we need to strip suffixes from it. |
| 497 | For instance, fields with alignment constraints will |
| 498 | have an __XVA suffix added to them. */ |
| 499 | const char *field_name = TYPE_FIELD_NAME (parent_type, fieldno); |
| 500 | int child_name_len = ada_name_prefix_len (field_name); |
| 501 | |
| 502 | *child_name = string_printf ("%.*s", child_name_len, field_name); |
| 503 | } |
| 504 | |
| 505 | if (child_value && parent_value) |
| 506 | ada_varobj_struct_elt (parent_value, parent_type, fieldno, |
| 507 | child_value, NULL); |
| 508 | |
| 509 | if (child_type) |
| 510 | ada_varobj_struct_elt (parent_value, parent_type, fieldno, |
| 511 | NULL, child_type); |
| 512 | |
| 513 | if (child_path_expr) |
| 514 | { |
| 515 | /* The name of the child is none other than the field's |
| 516 | name, except that we need to strip suffixes from it. |
| 517 | For instance, fields with alignment constraints will |
| 518 | have an __XVA suffix added to them. */ |
| 519 | const char *field_name = TYPE_FIELD_NAME (parent_type, fieldno); |
| 520 | int child_name_len = ada_name_prefix_len (field_name); |
| 521 | |
| 522 | *child_path_expr = |
| 523 | string_printf ("(%s).%.*s", parent_path_expr, |
| 524 | child_name_len, field_name); |
| 525 | } |
| 526 | |
| 527 | return; |
| 528 | } |
| 529 | |
| 530 | childno++; |
| 531 | } |
| 532 | |
| 533 | /* Something went wrong. Either we miscounted the number of |
| 534 | children, or CHILD_INDEX was too high. But we should never |
| 535 | reach here. We don't have enough information to recover |
| 536 | nicely, so just raise an assertion failure. */ |
| 537 | gdb_assert_not_reached ("unexpected code path"); |
| 538 | } |
| 539 | |
| 540 | /* Same as ada_varobj_describe_child, but limited to pointer objects. |
| 541 | |
| 542 | Note that CHILD_INDEX is unused in this situation, but still provided |
| 543 | for consistency of interface with other routines describing an object's |
| 544 | child. */ |
| 545 | |
| 546 | static void |
| 547 | ada_varobj_describe_ptr_child (struct value *parent_value, |
| 548 | struct type *parent_type, |
| 549 | const char *parent_name, |
| 550 | const char *parent_path_expr, |
| 551 | int child_index, |
| 552 | std::string *child_name, |
| 553 | struct value **child_value, |
| 554 | struct type **child_type, |
| 555 | std::string *child_path_expr) |
| 556 | { |
| 557 | if (child_name) |
| 558 | *child_name = string_printf ("%s.all", parent_name); |
| 559 | |
| 560 | if (child_value && parent_value) |
| 561 | ada_varobj_ind (parent_value, parent_type, child_value, NULL); |
| 562 | |
| 563 | if (child_type) |
| 564 | ada_varobj_ind (parent_value, parent_type, NULL, child_type); |
| 565 | |
| 566 | if (child_path_expr) |
| 567 | *child_path_expr = string_printf ("(%s).all", parent_path_expr); |
| 568 | } |
| 569 | |
| 570 | /* Same as ada_varobj_describe_child, limited to simple array objects |
| 571 | (TYPE_CODE_ARRAY only). |
| 572 | |
| 573 | Assumes that the (PARENT_VALUE, PARENT_TYPE) pair is properly decoded. |
| 574 | This is done by ada_varobj_describe_child before calling us. */ |
| 575 | |
| 576 | static void |
| 577 | ada_varobj_describe_simple_array_child (struct value *parent_value, |
| 578 | struct type *parent_type, |
| 579 | const char *parent_name, |
| 580 | const char *parent_path_expr, |
| 581 | int child_index, |
| 582 | std::string *child_name, |
| 583 | struct value **child_value, |
| 584 | struct type **child_type, |
| 585 | std::string *child_path_expr) |
| 586 | { |
| 587 | struct type *index_type; |
| 588 | int real_index; |
| 589 | |
| 590 | gdb_assert (TYPE_CODE (parent_type) == TYPE_CODE_ARRAY); |
| 591 | |
| 592 | index_type = TYPE_INDEX_TYPE (parent_type); |
| 593 | real_index = child_index + ada_discrete_type_low_bound (index_type); |
| 594 | |
| 595 | if (child_name) |
| 596 | *child_name = ada_varobj_scalar_image (index_type, real_index); |
| 597 | |
| 598 | if (child_value && parent_value) |
| 599 | ada_varobj_simple_array_elt (parent_value, parent_type, real_index, |
| 600 | child_value, NULL); |
| 601 | |
| 602 | if (child_type) |
| 603 | ada_varobj_simple_array_elt (parent_value, parent_type, real_index, |
| 604 | NULL, child_type); |
| 605 | |
| 606 | if (child_path_expr) |
| 607 | { |
| 608 | std::string index_img = ada_varobj_scalar_image (index_type, real_index); |
| 609 | |
| 610 | /* Enumeration litterals by themselves are potentially ambiguous. |
| 611 | For instance, consider the following package spec: |
| 612 | |
| 613 | package Pck is |
| 614 | type Color is (Red, Green, Blue, White); |
| 615 | type Blood_Cells is (White, Red); |
| 616 | end Pck; |
| 617 | |
| 618 | In this case, the litteral "red" for instance, or even |
| 619 | the fully-qualified litteral "pck.red" cannot be resolved |
| 620 | by itself. Type qualification is needed to determine which |
| 621 | enumeration litterals should be used. |
| 622 | |
| 623 | The following variable will be used to contain the name |
| 624 | of the array index type when such type qualification is |
| 625 | needed. */ |
| 626 | const char *index_type_name = NULL; |
| 627 | |
| 628 | /* If the index type is a range type, find the base type. */ |
| 629 | while (TYPE_CODE (index_type) == TYPE_CODE_RANGE) |
| 630 | index_type = TYPE_TARGET_TYPE (index_type); |
| 631 | |
| 632 | if (TYPE_CODE (index_type) == TYPE_CODE_ENUM |
| 633 | || TYPE_CODE (index_type) == TYPE_CODE_BOOL) |
| 634 | { |
| 635 | index_type_name = ada_type_name (index_type); |
| 636 | if (index_type_name) |
| 637 | index_type_name = ada_decode (index_type_name); |
| 638 | } |
| 639 | |
| 640 | if (index_type_name != NULL) |
| 641 | *child_path_expr = |
| 642 | string_printf ("(%s)(%.*s'(%s))", parent_path_expr, |
| 643 | ada_name_prefix_len (index_type_name), |
| 644 | index_type_name, index_img.c_str ()); |
| 645 | else |
| 646 | *child_path_expr = |
| 647 | string_printf ("(%s)(%s)", parent_path_expr, index_img.c_str ()); |
| 648 | } |
| 649 | } |
| 650 | |
| 651 | /* See description at declaration above. */ |
| 652 | |
| 653 | static void |
| 654 | ada_varobj_describe_child (struct value *parent_value, |
| 655 | struct type *parent_type, |
| 656 | const char *parent_name, |
| 657 | const char *parent_path_expr, |
| 658 | int child_index, |
| 659 | std::string *child_name, |
| 660 | struct value **child_value, |
| 661 | struct type **child_type, |
| 662 | std::string *child_path_expr) |
| 663 | { |
| 664 | /* We cannot compute the child's path expression without |
| 665 | the parent's path expression. This is a pre-condition |
| 666 | for calling this function. */ |
| 667 | if (child_path_expr) |
| 668 | gdb_assert (parent_path_expr != NULL); |
| 669 | |
| 670 | ada_varobj_decode_var (&parent_value, &parent_type); |
| 671 | ada_varobj_adjust_for_child_access (&parent_value, &parent_type); |
| 672 | |
| 673 | if (child_name) |
| 674 | *child_name = std::string (); |
| 675 | if (child_value) |
| 676 | *child_value = NULL; |
| 677 | if (child_type) |
| 678 | *child_type = NULL; |
| 679 | if (child_path_expr) |
| 680 | *child_path_expr = std::string (); |
| 681 | |
| 682 | if (ada_is_array_descriptor_type (parent_type) |
| 683 | && TYPE_CODE (parent_type) == TYPE_CODE_TYPEDEF) |
| 684 | { |
| 685 | ada_varobj_describe_ptr_child (parent_value, parent_type, |
| 686 | parent_name, parent_path_expr, |
| 687 | child_index, child_name, |
| 688 | child_value, child_type, |
| 689 | child_path_expr); |
| 690 | return; |
| 691 | } |
| 692 | |
| 693 | if (TYPE_CODE (parent_type) == TYPE_CODE_ARRAY) |
| 694 | { |
| 695 | ada_varobj_describe_simple_array_child |
| 696 | (parent_value, parent_type, parent_name, parent_path_expr, |
| 697 | child_index, child_name, child_value, child_type, |
| 698 | child_path_expr); |
| 699 | return; |
| 700 | } |
| 701 | |
| 702 | if (TYPE_CODE (parent_type) == TYPE_CODE_STRUCT) |
| 703 | { |
| 704 | ada_varobj_describe_struct_child (parent_value, parent_type, |
| 705 | parent_name, parent_path_expr, |
| 706 | child_index, child_name, |
| 707 | child_value, child_type, |
| 708 | child_path_expr); |
| 709 | return; |
| 710 | } |
| 711 | |
| 712 | if (TYPE_CODE (parent_type) == TYPE_CODE_PTR) |
| 713 | { |
| 714 | ada_varobj_describe_ptr_child (parent_value, parent_type, |
| 715 | parent_name, parent_path_expr, |
| 716 | child_index, child_name, |
| 717 | child_value, child_type, |
| 718 | child_path_expr); |
| 719 | return; |
| 720 | } |
| 721 | |
| 722 | /* It should never happen. But rather than crash, report dummy names |
| 723 | and return a NULL child_value. */ |
| 724 | if (child_name) |
| 725 | *child_name = "???"; |
| 726 | } |
| 727 | |
| 728 | /* Return the name of the child number CHILD_INDEX of the (PARENT_VALUE, |
| 729 | PARENT_TYPE) pair. PARENT_NAME is the name of the PARENT. */ |
| 730 | |
| 731 | static std::string |
| 732 | ada_varobj_get_name_of_child (struct value *parent_value, |
| 733 | struct type *parent_type, |
| 734 | const char *parent_name, int child_index) |
| 735 | { |
| 736 | std::string child_name; |
| 737 | |
| 738 | ada_varobj_describe_child (parent_value, parent_type, parent_name, |
| 739 | NULL, child_index, &child_name, NULL, |
| 740 | NULL, NULL); |
| 741 | return child_name; |
| 742 | } |
| 743 | |
| 744 | /* Return the path expression of the child number CHILD_INDEX of |
| 745 | the (PARENT_VALUE, PARENT_TYPE) pair. PARENT_NAME is the name |
| 746 | of the parent, and PARENT_PATH_EXPR is the parent's path expression. |
| 747 | Both must be non-NULL. */ |
| 748 | |
| 749 | static std::string |
| 750 | ada_varobj_get_path_expr_of_child (struct value *parent_value, |
| 751 | struct type *parent_type, |
| 752 | const char *parent_name, |
| 753 | const char *parent_path_expr, |
| 754 | int child_index) |
| 755 | { |
| 756 | std::string child_path_expr; |
| 757 | |
| 758 | ada_varobj_describe_child (parent_value, parent_type, parent_name, |
| 759 | parent_path_expr, child_index, NULL, |
| 760 | NULL, NULL, &child_path_expr); |
| 761 | |
| 762 | return child_path_expr; |
| 763 | } |
| 764 | |
| 765 | /* Return the value of child number CHILD_INDEX of the (PARENT_VALUE, |
| 766 | PARENT_TYPE) pair. PARENT_NAME is the name of the parent. */ |
| 767 | |
| 768 | static struct value * |
| 769 | ada_varobj_get_value_of_child (struct value *parent_value, |
| 770 | struct type *parent_type, |
| 771 | const char *parent_name, int child_index) |
| 772 | { |
| 773 | struct value *child_value; |
| 774 | |
| 775 | ada_varobj_describe_child (parent_value, parent_type, parent_name, |
| 776 | NULL, child_index, NULL, &child_value, |
| 777 | NULL, NULL); |
| 778 | |
| 779 | return child_value; |
| 780 | } |
| 781 | |
| 782 | /* Return the type of child number CHILD_INDEX of the (PARENT_VALUE, |
| 783 | PARENT_TYPE) pair. */ |
| 784 | |
| 785 | static struct type * |
| 786 | ada_varobj_get_type_of_child (struct value *parent_value, |
| 787 | struct type *parent_type, |
| 788 | int child_index) |
| 789 | { |
| 790 | struct type *child_type; |
| 791 | |
| 792 | ada_varobj_describe_child (parent_value, parent_type, NULL, NULL, |
| 793 | child_index, NULL, NULL, &child_type, NULL); |
| 794 | |
| 795 | return child_type; |
| 796 | } |
| 797 | |
| 798 | /* Return a string that contains the image of the given VALUE, using |
| 799 | the print options OPTS as the options for formatting the result. |
| 800 | |
| 801 | The resulting string must be deallocated after use with xfree. */ |
| 802 | |
| 803 | static std::string |
| 804 | ada_varobj_get_value_image (struct value *value, |
| 805 | struct value_print_options *opts) |
| 806 | { |
| 807 | string_file buffer; |
| 808 | |
| 809 | common_val_print (value, &buffer, 0, opts, current_language); |
| 810 | return std::move (buffer.string ()); |
| 811 | } |
| 812 | |
| 813 | /* Assuming that the (VALUE, TYPE) pair designates an array varobj, |
| 814 | return a string that is suitable for use in the "value" field of |
| 815 | the varobj output. Most of the time, this is the number of elements |
| 816 | in the array inside square brackets, but there are situations where |
| 817 | it's useful to add more info. |
| 818 | |
| 819 | OPTS are the print options used when formatting the result. |
| 820 | |
| 821 | The result should be deallocated after use using xfree. */ |
| 822 | |
| 823 | static std::string |
| 824 | ada_varobj_get_value_of_array_variable (struct value *value, |
| 825 | struct type *type, |
| 826 | struct value_print_options *opts) |
| 827 | { |
| 828 | char *result; |
| 829 | const int numchild = ada_varobj_get_array_number_of_children (value, type); |
| 830 | |
| 831 | /* If we have a string, provide its contents in the "value" field. |
| 832 | Otherwise, the only other way to inspect the contents of the string |
| 833 | is by looking at the value of each element, as in any other array, |
| 834 | which is not very convenient... */ |
| 835 | if (value |
| 836 | && ada_is_string_type (type) |
| 837 | && (opts->format == 0 || opts->format == 's')) |
| 838 | { |
| 839 | std::string str = ada_varobj_get_value_image (value, opts); |
| 840 | return string_printf ("[%d] %s", numchild, str.c_str ()); |
| 841 | } |
| 842 | else |
| 843 | return string_printf ("[%d]", numchild); |
| 844 | } |
| 845 | |
| 846 | /* Return a string representation of the (VALUE, TYPE) pair, using |
| 847 | the given print options OPTS as our formatting options. */ |
| 848 | |
| 849 | static std::string |
| 850 | ada_varobj_get_value_of_variable (struct value *value, |
| 851 | struct type *type, |
| 852 | struct value_print_options *opts) |
| 853 | { |
| 854 | ada_varobj_decode_var (&value, &type); |
| 855 | |
| 856 | switch (TYPE_CODE (type)) |
| 857 | { |
| 858 | case TYPE_CODE_STRUCT: |
| 859 | case TYPE_CODE_UNION: |
| 860 | return "{...}"; |
| 861 | case TYPE_CODE_ARRAY: |
| 862 | return ada_varobj_get_value_of_array_variable (value, type, opts); |
| 863 | default: |
| 864 | if (!value) |
| 865 | return ""; |
| 866 | else |
| 867 | return ada_varobj_get_value_image (value, opts); |
| 868 | } |
| 869 | } |
| 870 | |
| 871 | /* Ada specific callbacks for VAROBJs. */ |
| 872 | |
| 873 | static int |
| 874 | ada_number_of_children (const struct varobj *var) |
| 875 | { |
| 876 | return ada_varobj_get_number_of_children (var->value, var->type); |
| 877 | } |
| 878 | |
| 879 | static std::string |
| 880 | ada_name_of_variable (const struct varobj *parent) |
| 881 | { |
| 882 | return c_varobj_ops.name_of_variable (parent); |
| 883 | } |
| 884 | |
| 885 | static std::string |
| 886 | ada_name_of_child (const struct varobj *parent, int index) |
| 887 | { |
| 888 | return ada_varobj_get_name_of_child (parent->value, parent->type, |
| 889 | parent->name.c_str (), index); |
| 890 | } |
| 891 | |
| 892 | static std::string |
| 893 | ada_path_expr_of_child (const struct varobj *child) |
| 894 | { |
| 895 | const struct varobj *parent = child->parent; |
| 896 | const char *parent_path_expr = varobj_get_path_expr (parent); |
| 897 | |
| 898 | return ada_varobj_get_path_expr_of_child (parent->value, |
| 899 | parent->type, |
| 900 | parent->name.c_str (), |
| 901 | parent_path_expr, |
| 902 | child->index); |
| 903 | } |
| 904 | |
| 905 | static struct value * |
| 906 | ada_value_of_child (const struct varobj *parent, int index) |
| 907 | { |
| 908 | return ada_varobj_get_value_of_child (parent->value, parent->type, |
| 909 | parent->name.c_str (), index); |
| 910 | } |
| 911 | |
| 912 | static struct type * |
| 913 | ada_type_of_child (const struct varobj *parent, int index) |
| 914 | { |
| 915 | return ada_varobj_get_type_of_child (parent->value, parent->type, |
| 916 | index); |
| 917 | } |
| 918 | |
| 919 | static std::string |
| 920 | ada_value_of_variable (const struct varobj *var, |
| 921 | enum varobj_display_formats format) |
| 922 | { |
| 923 | struct value_print_options opts; |
| 924 | |
| 925 | varobj_formatted_print_options (&opts, format); |
| 926 | |
| 927 | return ada_varobj_get_value_of_variable (var->value, var->type, &opts); |
| 928 | } |
| 929 | |
| 930 | /* Implement the "value_is_changeable_p" routine for Ada. */ |
| 931 | |
| 932 | static int |
| 933 | ada_value_is_changeable_p (const struct varobj *var) |
| 934 | { |
| 935 | struct type *type = var->value ? value_type (var->value) : var->type; |
| 936 | |
| 937 | if (ada_is_array_descriptor_type (type) |
| 938 | && TYPE_CODE (type) == TYPE_CODE_TYPEDEF) |
| 939 | { |
| 940 | /* This is in reality a pointer to an unconstrained array. |
| 941 | its value is changeable. */ |
| 942 | return 1; |
| 943 | } |
| 944 | |
| 945 | if (ada_is_string_type (type)) |
| 946 | { |
| 947 | /* We display the contents of the string in the array's |
| 948 | "value" field. The contents can change, so consider |
| 949 | that the array is changeable. */ |
| 950 | return 1; |
| 951 | } |
| 952 | |
| 953 | return varobj_default_value_is_changeable_p (var); |
| 954 | } |
| 955 | |
| 956 | /* Implement the "value_has_mutated" routine for Ada. */ |
| 957 | |
| 958 | static int |
| 959 | ada_value_has_mutated (const struct varobj *var, struct value *new_val, |
| 960 | struct type *new_type) |
| 961 | { |
| 962 | int i; |
| 963 | int from = -1; |
| 964 | int to = -1; |
| 965 | |
| 966 | /* If the number of fields have changed, then for sure the type |
| 967 | has mutated. */ |
| 968 | if (ada_varobj_get_number_of_children (new_val, new_type) |
| 969 | != var->num_children) |
| 970 | return 1; |
| 971 | |
| 972 | /* If the number of fields have remained the same, then we need |
| 973 | to check the name of each field. If they remain the same, |
| 974 | then chances are the type hasn't mutated. This is technically |
| 975 | an incomplete test, as the child's type might have changed |
| 976 | despite the fact that the name remains the same. But we'll |
| 977 | handle this situation by saying that the child has mutated, |
| 978 | not this value. |
| 979 | |
| 980 | If only part (or none!) of the children have been fetched, |
| 981 | then only check the ones we fetched. It does not matter |
| 982 | to the frontend whether a child that it has not fetched yet |
| 983 | has mutated or not. So just assume it hasn't. */ |
| 984 | |
| 985 | varobj_restrict_range (var->children, &from, &to); |
| 986 | for (i = from; i < to; i++) |
| 987 | if (ada_varobj_get_name_of_child (new_val, new_type, |
| 988 | var->name.c_str (), i) |
| 989 | != VEC_index (varobj_p, var->children, i)->name) |
| 990 | return 1; |
| 991 | |
| 992 | return 0; |
| 993 | } |
| 994 | |
| 995 | /* varobj operations for ada. */ |
| 996 | |
| 997 | const struct lang_varobj_ops ada_varobj_ops = |
| 998 | { |
| 999 | ada_number_of_children, |
| 1000 | ada_name_of_variable, |
| 1001 | ada_name_of_child, |
| 1002 | ada_path_expr_of_child, |
| 1003 | ada_value_of_child, |
| 1004 | ada_type_of_child, |
| 1005 | ada_value_of_variable, |
| 1006 | ada_value_is_changeable_p, |
| 1007 | ada_value_has_mutated, |
| 1008 | varobj_default_is_path_expr_parent |
| 1009 | }; |