| 1 | /* Routines for name->symbol lookups in GDB. |
| 2 | |
| 3 | Copyright (C) 2003, 2007, 2008, 2009 Free Software Foundation, Inc. |
| 4 | |
| 5 | Contributed by David Carlton <carlton@bactrian.org> and by Kealia, |
| 6 | Inc. |
| 7 | |
| 8 | This file is part of GDB. |
| 9 | |
| 10 | This program is free software; you can redistribute it and/or modify |
| 11 | it under the terms of the GNU General Public License as published by |
| 12 | the Free Software Foundation; either version 3 of the License, or |
| 13 | (at your option) any later version. |
| 14 | |
| 15 | This program is distributed in the hope that it will be useful, |
| 16 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 17 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 18 | GNU General Public License for more details. |
| 19 | |
| 20 | You should have received a copy of the GNU General Public License |
| 21 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
| 22 | |
| 23 | #include "defs.h" |
| 24 | #include "gdb_obstack.h" |
| 25 | #include "symtab.h" |
| 26 | #include "buildsym.h" |
| 27 | #include "gdb_assert.h" |
| 28 | #include "dictionary.h" |
| 29 | |
| 30 | /* This file implements dictionaries, which are tables that associate |
| 31 | symbols to names. They are represented by an opaque type 'struct |
| 32 | dictionary'. That type has various internal implementations, which |
| 33 | you can choose between depending on what properties you need |
| 34 | (e.g. fast lookup, order-preserving, expandable). |
| 35 | |
| 36 | Each dictionary starts with a 'virtual function table' that |
| 37 | contains the functions that actually implement the various |
| 38 | operations that dictionaries provide. (Note, however, that, for |
| 39 | the sake of client code, we also provide some functions that can be |
| 40 | implemented generically in terms of the functions in the vtable.) |
| 41 | |
| 42 | To add a new dictionary implementation <impl>, what you should do |
| 43 | is: |
| 44 | |
| 45 | * Add a new element DICT_<IMPL> to dict_type. |
| 46 | |
| 47 | * Create a new structure dictionary_<impl>. If your new |
| 48 | implementation is a variant of an existing one, make sure that |
| 49 | their structs have the same initial data members. Define accessor |
| 50 | macros for your new data members. |
| 51 | |
| 52 | * Implement all the functions in dict_vector as static functions, |
| 53 | whose name is the same as the corresponding member of dict_vector |
| 54 | plus _<impl>. You don't have to do this for those members where |
| 55 | you can reuse existing generic functions |
| 56 | (e.g. add_symbol_nonexpandable, free_obstack) or in the case where |
| 57 | your new implementation is a variant of an existing implementation |
| 58 | and where the variant doesn't affect the member function in |
| 59 | question. |
| 60 | |
| 61 | * Define a static const struct dict_vector dict_<impl>_vector. |
| 62 | |
| 63 | * Define a function dict_create_<impl> to create these |
| 64 | gizmos. Add its declaration to dictionary.h. |
| 65 | |
| 66 | To add a new operation <op> on all existing implementations, what |
| 67 | you should do is: |
| 68 | |
| 69 | * Add a new member <op> to struct dict_vector. |
| 70 | |
| 71 | * If there is useful generic behavior <op>, define a static |
| 72 | function <op>_something_informative that implements that behavior. |
| 73 | (E.g. add_symbol_nonexpandable, free_obstack.) |
| 74 | |
| 75 | * For every implementation <impl> that should have its own specific |
| 76 | behavior for <op>, define a static function <op>_<impl> |
| 77 | implementing it. |
| 78 | |
| 79 | * Modify all existing dict_vector_<impl>'s to include the appropriate |
| 80 | member. |
| 81 | |
| 82 | * Define a function dict_<op> that looks up <op> in the dict_vector |
| 83 | and calls the appropriate function. Add a declaration for |
| 84 | dict_<op> to dictionary.h. |
| 85 | |
| 86 | */ |
| 87 | |
| 88 | /* An enum representing the various implementations of dictionaries. |
| 89 | Used only for debugging. */ |
| 90 | |
| 91 | enum dict_type |
| 92 | { |
| 93 | /* Symbols are stored in a fixed-size hash table. */ |
| 94 | DICT_HASHED, |
| 95 | /* Symbols are stored in an expandable hash table. */ |
| 96 | DICT_HASHED_EXPANDABLE, |
| 97 | /* Symbols are stored in a fixed-size array. */ |
| 98 | DICT_LINEAR, |
| 99 | /* Symbols are stored in an expandable array. */ |
| 100 | DICT_LINEAR_EXPANDABLE |
| 101 | }; |
| 102 | |
| 103 | /* The virtual function table. */ |
| 104 | |
| 105 | struct dict_vector |
| 106 | { |
| 107 | /* The type of the dictionary. This is only here to make debugging |
| 108 | a bit easier; it's not actually used. */ |
| 109 | enum dict_type type; |
| 110 | /* The function to free a dictionary. */ |
| 111 | void (*free) (struct dictionary *dict); |
| 112 | /* Add a symbol to a dictionary, if possible. */ |
| 113 | void (*add_symbol) (struct dictionary *dict, struct symbol *sym); |
| 114 | /* Iterator functions. */ |
| 115 | struct symbol *(*iterator_first) (const struct dictionary *dict, |
| 116 | struct dict_iterator *iterator); |
| 117 | struct symbol *(*iterator_next) (struct dict_iterator *iterator); |
| 118 | /* Functions to iterate over symbols with a given name. */ |
| 119 | struct symbol *(*iter_name_first) (const struct dictionary *dict, |
| 120 | const char *name, |
| 121 | struct dict_iterator *iterator); |
| 122 | struct symbol *(*iter_name_next) (const char *name, |
| 123 | struct dict_iterator *iterator); |
| 124 | /* A size function, for maint print symtabs. */ |
| 125 | int (*size) (const struct dictionary *dict); |
| 126 | }; |
| 127 | |
| 128 | /* Now comes the structs used to store the data for different |
| 129 | implementations. If two implementations have data in common, put |
| 130 | the common data at the top of their structs, ordered in the same |
| 131 | way. */ |
| 132 | |
| 133 | struct dictionary_hashed |
| 134 | { |
| 135 | int nbuckets; |
| 136 | struct symbol **buckets; |
| 137 | }; |
| 138 | |
| 139 | struct dictionary_hashed_expandable |
| 140 | { |
| 141 | /* How many buckets we currently have. */ |
| 142 | int nbuckets; |
| 143 | struct symbol **buckets; |
| 144 | /* How many syms we currently have; we need this so we will know |
| 145 | when to add more buckets. */ |
| 146 | int nsyms; |
| 147 | }; |
| 148 | |
| 149 | struct dictionary_linear |
| 150 | { |
| 151 | int nsyms; |
| 152 | struct symbol **syms; |
| 153 | }; |
| 154 | |
| 155 | struct dictionary_linear_expandable |
| 156 | { |
| 157 | /* How many symbols we currently have. */ |
| 158 | int nsyms; |
| 159 | struct symbol **syms; |
| 160 | /* How many symbols we can store before needing to reallocate. */ |
| 161 | int capacity; |
| 162 | }; |
| 163 | |
| 164 | /* And now, the star of our show. */ |
| 165 | |
| 166 | struct dictionary |
| 167 | { |
| 168 | const struct dict_vector *vector; |
| 169 | union |
| 170 | { |
| 171 | struct dictionary_hashed hashed; |
| 172 | struct dictionary_hashed_expandable hashed_expandable; |
| 173 | struct dictionary_linear linear; |
| 174 | struct dictionary_linear_expandable linear_expandable; |
| 175 | } |
| 176 | data; |
| 177 | }; |
| 178 | |
| 179 | /* Accessor macros. */ |
| 180 | |
| 181 | #define DICT_VECTOR(d) (d)->vector |
| 182 | |
| 183 | /* These can be used for DICT_HASHED_EXPANDABLE, too. */ |
| 184 | |
| 185 | #define DICT_HASHED_NBUCKETS(d) (d)->data.hashed.nbuckets |
| 186 | #define DICT_HASHED_BUCKETS(d) (d)->data.hashed.buckets |
| 187 | #define DICT_HASHED_BUCKET(d,i) DICT_HASHED_BUCKETS (d) [i] |
| 188 | |
| 189 | #define DICT_HASHED_EXPANDABLE_NSYMS(d) (d)->data.hashed_expandable.nsyms |
| 190 | |
| 191 | /* These can be used for DICT_LINEAR_EXPANDABLEs, too. */ |
| 192 | |
| 193 | #define DICT_LINEAR_NSYMS(d) (d)->data.linear.nsyms |
| 194 | #define DICT_LINEAR_SYMS(d) (d)->data.linear.syms |
| 195 | #define DICT_LINEAR_SYM(d,i) DICT_LINEAR_SYMS (d) [i] |
| 196 | |
| 197 | #define DICT_LINEAR_EXPANDABLE_CAPACITY(d) \ |
| 198 | (d)->data.linear_expandable.capacity |
| 199 | |
| 200 | /* The initial size of a DICT_*_EXPANDABLE dictionary. */ |
| 201 | |
| 202 | #define DICT_EXPANDABLE_INITIAL_CAPACITY 10 |
| 203 | |
| 204 | /* This calculates the number of buckets we'll use in a hashtable, |
| 205 | given the number of symbols that it will contain. */ |
| 206 | |
| 207 | #define DICT_HASHTABLE_SIZE(n) ((n)/5 + 1) |
| 208 | |
| 209 | /* Accessor macros for dict_iterators; they're here rather than |
| 210 | dictionary.h because code elsewhere should treat dict_iterators as |
| 211 | opaque. */ |
| 212 | |
| 213 | /* The dictionary that the iterator is associated to. */ |
| 214 | #define DICT_ITERATOR_DICT(iter) (iter)->dict |
| 215 | /* For linear dictionaries, the index of the last symbol returned; for |
| 216 | hashed dictionaries, the bucket of the last symbol returned. */ |
| 217 | #define DICT_ITERATOR_INDEX(iter) (iter)->index |
| 218 | /* For hashed dictionaries, this points to the last symbol returned; |
| 219 | otherwise, this is unused. */ |
| 220 | #define DICT_ITERATOR_CURRENT(iter) (iter)->current |
| 221 | |
| 222 | /* Declarations of functions for vectors. */ |
| 223 | |
| 224 | /* Functions that might work across a range of dictionary types. */ |
| 225 | |
| 226 | static void add_symbol_nonexpandable (struct dictionary *dict, |
| 227 | struct symbol *sym); |
| 228 | |
| 229 | static void free_obstack (struct dictionary *dict); |
| 230 | |
| 231 | /* Functions for DICT_HASHED and DICT_HASHED_EXPANDABLE |
| 232 | dictionaries. */ |
| 233 | |
| 234 | static struct symbol *iterator_first_hashed (const struct dictionary *dict, |
| 235 | struct dict_iterator *iterator); |
| 236 | |
| 237 | static struct symbol *iterator_next_hashed (struct dict_iterator *iterator); |
| 238 | |
| 239 | static struct symbol *iter_name_first_hashed (const struct dictionary *dict, |
| 240 | const char *name, |
| 241 | struct dict_iterator *iterator); |
| 242 | |
| 243 | static struct symbol *iter_name_next_hashed (const char *name, |
| 244 | struct dict_iterator *iterator); |
| 245 | |
| 246 | /* Functions only for DICT_HASHED. */ |
| 247 | |
| 248 | static int size_hashed (const struct dictionary *dict); |
| 249 | |
| 250 | /* Functions only for DICT_HASHED_EXPANDABLE. */ |
| 251 | |
| 252 | static void free_hashed_expandable (struct dictionary *dict); |
| 253 | |
| 254 | static void add_symbol_hashed_expandable (struct dictionary *dict, |
| 255 | struct symbol *sym); |
| 256 | |
| 257 | static int size_hashed_expandable (const struct dictionary *dict); |
| 258 | |
| 259 | /* Functions for DICT_LINEAR and DICT_LINEAR_EXPANDABLE |
| 260 | dictionaries. */ |
| 261 | |
| 262 | static struct symbol *iterator_first_linear (const struct dictionary *dict, |
| 263 | struct dict_iterator *iterator); |
| 264 | |
| 265 | static struct symbol *iterator_next_linear (struct dict_iterator *iterator); |
| 266 | |
| 267 | static struct symbol *iter_name_first_linear (const struct dictionary *dict, |
| 268 | const char *name, |
| 269 | struct dict_iterator *iterator); |
| 270 | |
| 271 | static struct symbol *iter_name_next_linear (const char *name, |
| 272 | struct dict_iterator *iterator); |
| 273 | |
| 274 | static int size_linear (const struct dictionary *dict); |
| 275 | |
| 276 | /* Functions only for DICT_LINEAR_EXPANDABLE. */ |
| 277 | |
| 278 | static void free_linear_expandable (struct dictionary *dict); |
| 279 | |
| 280 | static void add_symbol_linear_expandable (struct dictionary *dict, |
| 281 | struct symbol *sym); |
| 282 | |
| 283 | /* Various vectors that we'll actually use. */ |
| 284 | |
| 285 | static const struct dict_vector dict_hashed_vector = |
| 286 | { |
| 287 | DICT_HASHED, /* type */ |
| 288 | free_obstack, /* free */ |
| 289 | add_symbol_nonexpandable, /* add_symbol */ |
| 290 | iterator_first_hashed, /* iteractor_first */ |
| 291 | iterator_next_hashed, /* iterator_next */ |
| 292 | iter_name_first_hashed, /* iter_name_first */ |
| 293 | iter_name_next_hashed, /* iter_name_next */ |
| 294 | size_hashed, /* size */ |
| 295 | }; |
| 296 | |
| 297 | static const struct dict_vector dict_hashed_expandable_vector = |
| 298 | { |
| 299 | DICT_HASHED_EXPANDABLE, /* type */ |
| 300 | free_hashed_expandable, /* free */ |
| 301 | add_symbol_hashed_expandable, /* add_symbol */ |
| 302 | iterator_first_hashed, /* iteractor_first */ |
| 303 | iterator_next_hashed, /* iterator_next */ |
| 304 | iter_name_first_hashed, /* iter_name_first */ |
| 305 | iter_name_next_hashed, /* iter_name_next */ |
| 306 | size_hashed_expandable, /* size */ |
| 307 | }; |
| 308 | |
| 309 | static const struct dict_vector dict_linear_vector = |
| 310 | { |
| 311 | DICT_LINEAR, /* type */ |
| 312 | free_obstack, /* free */ |
| 313 | add_symbol_nonexpandable, /* add_symbol */ |
| 314 | iterator_first_linear, /* iteractor_first */ |
| 315 | iterator_next_linear, /* iterator_next */ |
| 316 | iter_name_first_linear, /* iter_name_first */ |
| 317 | iter_name_next_linear, /* iter_name_next */ |
| 318 | size_linear, /* size */ |
| 319 | }; |
| 320 | |
| 321 | static const struct dict_vector dict_linear_expandable_vector = |
| 322 | { |
| 323 | DICT_LINEAR_EXPANDABLE, /* type */ |
| 324 | free_linear_expandable, /* free */ |
| 325 | add_symbol_linear_expandable, /* add_symbol */ |
| 326 | iterator_first_linear, /* iteractor_first */ |
| 327 | iterator_next_linear, /* iterator_next */ |
| 328 | iter_name_first_linear, /* iter_name_first */ |
| 329 | iter_name_next_linear, /* iter_name_next */ |
| 330 | size_linear, /* size */ |
| 331 | }; |
| 332 | |
| 333 | /* Declarations of helper functions (i.e. ones that don't go into |
| 334 | vectors). */ |
| 335 | |
| 336 | static struct symbol *iterator_hashed_advance (struct dict_iterator *iter); |
| 337 | |
| 338 | static void insert_symbol_hashed (struct dictionary *dict, |
| 339 | struct symbol *sym); |
| 340 | |
| 341 | static void expand_hashtable (struct dictionary *dict); |
| 342 | |
| 343 | /* The creation functions. */ |
| 344 | |
| 345 | /* Create a dictionary implemented via a fixed-size hashtable. All |
| 346 | memory it uses is allocated on OBSTACK; the environment is |
| 347 | initialized from SYMBOL_LIST. */ |
| 348 | |
| 349 | struct dictionary * |
| 350 | dict_create_hashed (struct obstack *obstack, |
| 351 | const struct pending *symbol_list) |
| 352 | { |
| 353 | struct dictionary *retval; |
| 354 | int nsyms = 0, nbuckets, i; |
| 355 | struct symbol **buckets; |
| 356 | const struct pending *list_counter; |
| 357 | |
| 358 | retval = obstack_alloc (obstack, sizeof (struct dictionary)); |
| 359 | DICT_VECTOR (retval) = &dict_hashed_vector; |
| 360 | |
| 361 | /* Calculate the number of symbols, and allocate space for them. */ |
| 362 | for (list_counter = symbol_list; |
| 363 | list_counter != NULL; |
| 364 | list_counter = list_counter->next) |
| 365 | { |
| 366 | nsyms += list_counter->nsyms; |
| 367 | } |
| 368 | nbuckets = DICT_HASHTABLE_SIZE (nsyms); |
| 369 | DICT_HASHED_NBUCKETS (retval) = nbuckets; |
| 370 | buckets = obstack_alloc (obstack, nbuckets * sizeof (struct symbol *)); |
| 371 | memset (buckets, 0, nbuckets * sizeof (struct symbol *)); |
| 372 | DICT_HASHED_BUCKETS (retval) = buckets; |
| 373 | |
| 374 | /* Now fill the buckets. */ |
| 375 | for (list_counter = symbol_list; |
| 376 | list_counter != NULL; |
| 377 | list_counter = list_counter->next) |
| 378 | { |
| 379 | for (i = list_counter->nsyms - 1; i >= 0; --i) |
| 380 | { |
| 381 | insert_symbol_hashed (retval, list_counter->symbol[i]); |
| 382 | } |
| 383 | } |
| 384 | |
| 385 | return retval; |
| 386 | } |
| 387 | |
| 388 | /* Create a dictionary implemented via a hashtable that grows as |
| 389 | necessary. The dictionary is initially empty; to add symbols to |
| 390 | it, call dict_add_symbol(). Call dict_free() when you're done with |
| 391 | it. */ |
| 392 | |
| 393 | extern struct dictionary * |
| 394 | dict_create_hashed_expandable (void) |
| 395 | { |
| 396 | struct dictionary *retval; |
| 397 | |
| 398 | retval = xmalloc (sizeof (struct dictionary)); |
| 399 | DICT_VECTOR (retval) = &dict_hashed_expandable_vector; |
| 400 | DICT_HASHED_NBUCKETS (retval) = DICT_EXPANDABLE_INITIAL_CAPACITY; |
| 401 | DICT_HASHED_BUCKETS (retval) = xcalloc (DICT_EXPANDABLE_INITIAL_CAPACITY, |
| 402 | sizeof (struct symbol *)); |
| 403 | DICT_HASHED_EXPANDABLE_NSYMS (retval) = 0; |
| 404 | |
| 405 | return retval; |
| 406 | } |
| 407 | |
| 408 | /* Create a dictionary implemented via a fixed-size array. All memory |
| 409 | it uses is allocated on OBSTACK; the environment is initialized |
| 410 | from the SYMBOL_LIST. The symbols are ordered in the same order |
| 411 | that they're found in SYMBOL_LIST. */ |
| 412 | |
| 413 | struct dictionary * |
| 414 | dict_create_linear (struct obstack *obstack, |
| 415 | const struct pending *symbol_list) |
| 416 | { |
| 417 | struct dictionary *retval; |
| 418 | int nsyms = 0, i, j; |
| 419 | struct symbol **syms; |
| 420 | const struct pending *list_counter; |
| 421 | |
| 422 | retval = obstack_alloc (obstack, sizeof (struct dictionary)); |
| 423 | DICT_VECTOR (retval) = &dict_linear_vector; |
| 424 | |
| 425 | /* Calculate the number of symbols, and allocate space for them. */ |
| 426 | for (list_counter = symbol_list; |
| 427 | list_counter != NULL; |
| 428 | list_counter = list_counter->next) |
| 429 | { |
| 430 | nsyms += list_counter->nsyms; |
| 431 | } |
| 432 | DICT_LINEAR_NSYMS (retval) = nsyms; |
| 433 | syms = obstack_alloc (obstack, nsyms * sizeof (struct symbol *)); |
| 434 | DICT_LINEAR_SYMS (retval) = syms; |
| 435 | |
| 436 | /* Now fill in the symbols. Start filling in from the back, so as |
| 437 | to preserve the original order of the symbols. */ |
| 438 | for (list_counter = symbol_list, j = nsyms - 1; |
| 439 | list_counter != NULL; |
| 440 | list_counter = list_counter->next) |
| 441 | { |
| 442 | for (i = list_counter->nsyms - 1; |
| 443 | i >= 0; |
| 444 | --i, --j) |
| 445 | { |
| 446 | syms[j] = list_counter->symbol[i]; |
| 447 | } |
| 448 | } |
| 449 | |
| 450 | return retval; |
| 451 | } |
| 452 | |
| 453 | /* Create a dictionary implemented via an array that grows as |
| 454 | necessary. The dictionary is initially empty; to add symbols to |
| 455 | it, call dict_add_symbol(). Call dict_free() when you're done with |
| 456 | it. */ |
| 457 | |
| 458 | struct dictionary * |
| 459 | dict_create_linear_expandable (void) |
| 460 | { |
| 461 | struct dictionary *retval; |
| 462 | |
| 463 | retval = xmalloc (sizeof (struct dictionary)); |
| 464 | DICT_VECTOR (retval) = &dict_linear_expandable_vector; |
| 465 | DICT_LINEAR_NSYMS (retval) = 0; |
| 466 | DICT_LINEAR_EXPANDABLE_CAPACITY (retval) |
| 467 | = DICT_EXPANDABLE_INITIAL_CAPACITY; |
| 468 | DICT_LINEAR_SYMS (retval) |
| 469 | = xmalloc (DICT_LINEAR_EXPANDABLE_CAPACITY (retval) |
| 470 | * sizeof (struct symbol *)); |
| 471 | |
| 472 | return retval; |
| 473 | } |
| 474 | |
| 475 | /* The functions providing the dictionary interface. */ |
| 476 | |
| 477 | /* Free the memory used by a dictionary that's not on an obstack. (If |
| 478 | any.) */ |
| 479 | |
| 480 | void |
| 481 | dict_free (struct dictionary *dict) |
| 482 | { |
| 483 | (DICT_VECTOR (dict))->free (dict); |
| 484 | } |
| 485 | |
| 486 | /* Add SYM to DICT. DICT had better be expandable. */ |
| 487 | |
| 488 | void |
| 489 | dict_add_symbol (struct dictionary *dict, struct symbol *sym) |
| 490 | { |
| 491 | (DICT_VECTOR (dict))->add_symbol (dict, sym); |
| 492 | } |
| 493 | |
| 494 | /* Initialize ITERATOR to point at the first symbol in DICT, and |
| 495 | return that first symbol, or NULL if DICT is empty. */ |
| 496 | |
| 497 | struct symbol * |
| 498 | dict_iterator_first (const struct dictionary *dict, |
| 499 | struct dict_iterator *iterator) |
| 500 | { |
| 501 | return (DICT_VECTOR (dict))->iterator_first (dict, iterator); |
| 502 | } |
| 503 | |
| 504 | /* Advance ITERATOR, and return the next symbol, or NULL if there are |
| 505 | no more symbols. */ |
| 506 | |
| 507 | struct symbol * |
| 508 | dict_iterator_next (struct dict_iterator *iterator) |
| 509 | { |
| 510 | return (DICT_VECTOR (DICT_ITERATOR_DICT (iterator))) |
| 511 | ->iterator_next (iterator); |
| 512 | } |
| 513 | |
| 514 | struct symbol * |
| 515 | dict_iter_name_first (const struct dictionary *dict, |
| 516 | const char *name, |
| 517 | struct dict_iterator *iterator) |
| 518 | { |
| 519 | return (DICT_VECTOR (dict))->iter_name_first (dict, name, iterator); |
| 520 | } |
| 521 | |
| 522 | struct symbol * |
| 523 | dict_iter_name_next (const char *name, struct dict_iterator *iterator) |
| 524 | { |
| 525 | return (DICT_VECTOR (DICT_ITERATOR_DICT (iterator))) |
| 526 | ->iter_name_next (name, iterator); |
| 527 | } |
| 528 | |
| 529 | int |
| 530 | dict_size (const struct dictionary *dict) |
| 531 | { |
| 532 | return (DICT_VECTOR (dict))->size (dict); |
| 533 | } |
| 534 | |
| 535 | /* Now come functions (well, one function, currently) that are |
| 536 | implemented generically by means of the vtable. Typically, they're |
| 537 | rarely used. */ |
| 538 | |
| 539 | /* Test to see if DICT is empty. */ |
| 540 | |
| 541 | int |
| 542 | dict_empty (struct dictionary *dict) |
| 543 | { |
| 544 | struct dict_iterator iter; |
| 545 | |
| 546 | return (dict_iterator_first (dict, &iter) == NULL); |
| 547 | } |
| 548 | |
| 549 | |
| 550 | /* The functions implementing the dictionary interface. */ |
| 551 | |
| 552 | /* Generic functions, where appropriate. */ |
| 553 | |
| 554 | static void |
| 555 | free_obstack (struct dictionary *dict) |
| 556 | { |
| 557 | /* Do nothing! */ |
| 558 | } |
| 559 | |
| 560 | static void |
| 561 | add_symbol_nonexpandable (struct dictionary *dict, struct symbol *sym) |
| 562 | { |
| 563 | internal_error (__FILE__, __LINE__, |
| 564 | _("dict_add_symbol: non-expandable dictionary")); |
| 565 | } |
| 566 | |
| 567 | /* Functions for DICT_HASHED and DICT_HASHED_EXPANDABLE. */ |
| 568 | |
| 569 | static struct symbol * |
| 570 | iterator_first_hashed (const struct dictionary *dict, |
| 571 | struct dict_iterator *iterator) |
| 572 | { |
| 573 | DICT_ITERATOR_DICT (iterator) = dict; |
| 574 | DICT_ITERATOR_INDEX (iterator) = -1; |
| 575 | return iterator_hashed_advance (iterator); |
| 576 | } |
| 577 | |
| 578 | static struct symbol * |
| 579 | iterator_next_hashed (struct dict_iterator *iterator) |
| 580 | { |
| 581 | const struct dictionary *dict = DICT_ITERATOR_DICT (iterator); |
| 582 | struct symbol *next; |
| 583 | |
| 584 | next = DICT_ITERATOR_CURRENT (iterator)->hash_next; |
| 585 | |
| 586 | if (next == NULL) |
| 587 | return iterator_hashed_advance (iterator); |
| 588 | else |
| 589 | { |
| 590 | DICT_ITERATOR_CURRENT (iterator) = next; |
| 591 | return next; |
| 592 | } |
| 593 | } |
| 594 | |
| 595 | static struct symbol * |
| 596 | iterator_hashed_advance (struct dict_iterator *iterator) |
| 597 | { |
| 598 | const struct dictionary *dict = DICT_ITERATOR_DICT (iterator); |
| 599 | int nbuckets = DICT_HASHED_NBUCKETS (dict); |
| 600 | int i; |
| 601 | |
| 602 | for (i = DICT_ITERATOR_INDEX (iterator) + 1; i < nbuckets; ++i) |
| 603 | { |
| 604 | struct symbol *sym = DICT_HASHED_BUCKET (dict, i); |
| 605 | |
| 606 | if (sym != NULL) |
| 607 | { |
| 608 | DICT_ITERATOR_INDEX (iterator) = i; |
| 609 | DICT_ITERATOR_CURRENT (iterator) = sym; |
| 610 | return sym; |
| 611 | } |
| 612 | } |
| 613 | |
| 614 | return NULL; |
| 615 | } |
| 616 | |
| 617 | static struct symbol * |
| 618 | iter_name_first_hashed (const struct dictionary *dict, |
| 619 | const char *name, |
| 620 | struct dict_iterator *iterator) |
| 621 | { |
| 622 | unsigned int hash_index |
| 623 | = msymbol_hash_iw (name) % DICT_HASHED_NBUCKETS (dict); |
| 624 | struct symbol *sym; |
| 625 | |
| 626 | DICT_ITERATOR_DICT (iterator) = dict; |
| 627 | |
| 628 | /* Loop through the symbols in the given bucket, breaking when SYM |
| 629 | first matches. If SYM never matches, it will be set to NULL; |
| 630 | either way, we have the right return value. */ |
| 631 | |
| 632 | for (sym = DICT_HASHED_BUCKET (dict, hash_index); |
| 633 | sym != NULL; |
| 634 | sym = sym->hash_next) |
| 635 | { |
| 636 | /* Warning: the order of arguments to strcmp_iw matters! */ |
| 637 | if (strcmp_iw (SYMBOL_SEARCH_NAME (sym), name) == 0) |
| 638 | { |
| 639 | break; |
| 640 | } |
| 641 | |
| 642 | } |
| 643 | |
| 644 | DICT_ITERATOR_CURRENT (iterator) = sym; |
| 645 | return sym; |
| 646 | } |
| 647 | |
| 648 | static struct symbol * |
| 649 | iter_name_next_hashed (const char *name, struct dict_iterator *iterator) |
| 650 | { |
| 651 | struct symbol *next; |
| 652 | |
| 653 | for (next = DICT_ITERATOR_CURRENT (iterator)->hash_next; |
| 654 | next != NULL; |
| 655 | next = next->hash_next) |
| 656 | { |
| 657 | if (strcmp_iw (SYMBOL_SEARCH_NAME (next), name) == 0) |
| 658 | break; |
| 659 | } |
| 660 | |
| 661 | DICT_ITERATOR_CURRENT (iterator) = next; |
| 662 | |
| 663 | return next; |
| 664 | } |
| 665 | |
| 666 | /* Insert SYM into DICT. */ |
| 667 | |
| 668 | static void |
| 669 | insert_symbol_hashed (struct dictionary *dict, |
| 670 | struct symbol *sym) |
| 671 | { |
| 672 | unsigned int hash_index; |
| 673 | struct symbol **buckets = DICT_HASHED_BUCKETS (dict); |
| 674 | |
| 675 | hash_index = (msymbol_hash_iw (SYMBOL_SEARCH_NAME (sym)) |
| 676 | % DICT_HASHED_NBUCKETS (dict)); |
| 677 | sym->hash_next = buckets[hash_index]; |
| 678 | buckets[hash_index] = sym; |
| 679 | } |
| 680 | |
| 681 | static int |
| 682 | size_hashed (const struct dictionary *dict) |
| 683 | { |
| 684 | return DICT_HASHED_NBUCKETS (dict); |
| 685 | } |
| 686 | |
| 687 | /* Functions only for DICT_HASHED_EXPANDABLE. */ |
| 688 | |
| 689 | static void |
| 690 | free_hashed_expandable (struct dictionary *dict) |
| 691 | { |
| 692 | xfree (DICT_HASHED_BUCKETS (dict)); |
| 693 | xfree (dict); |
| 694 | } |
| 695 | |
| 696 | static void |
| 697 | add_symbol_hashed_expandable (struct dictionary *dict, |
| 698 | struct symbol *sym) |
| 699 | { |
| 700 | int nsyms = ++DICT_HASHED_EXPANDABLE_NSYMS (dict); |
| 701 | |
| 702 | if (DICT_HASHTABLE_SIZE (nsyms) > DICT_HASHED_NBUCKETS (dict)) |
| 703 | expand_hashtable (dict); |
| 704 | |
| 705 | insert_symbol_hashed (dict, sym); |
| 706 | DICT_HASHED_EXPANDABLE_NSYMS (dict) = nsyms; |
| 707 | } |
| 708 | |
| 709 | static int |
| 710 | size_hashed_expandable (const struct dictionary *dict) |
| 711 | { |
| 712 | return DICT_HASHED_EXPANDABLE_NSYMS (dict); |
| 713 | } |
| 714 | |
| 715 | static void |
| 716 | expand_hashtable (struct dictionary *dict) |
| 717 | { |
| 718 | int old_nbuckets = DICT_HASHED_NBUCKETS (dict); |
| 719 | struct symbol **old_buckets = DICT_HASHED_BUCKETS (dict); |
| 720 | int new_nbuckets = 2*old_nbuckets + 1; |
| 721 | struct symbol **new_buckets = xcalloc (new_nbuckets, |
| 722 | sizeof (struct symbol *)); |
| 723 | int i; |
| 724 | |
| 725 | DICT_HASHED_NBUCKETS (dict) = new_nbuckets; |
| 726 | DICT_HASHED_BUCKETS (dict) = new_buckets; |
| 727 | |
| 728 | for (i = 0; i < old_nbuckets; ++i) { |
| 729 | struct symbol *sym, *next_sym; |
| 730 | |
| 731 | sym = old_buckets[i]; |
| 732 | if (sym != NULL) { |
| 733 | for (next_sym = sym->hash_next; |
| 734 | next_sym != NULL; |
| 735 | next_sym = sym->hash_next) { |
| 736 | insert_symbol_hashed (dict, sym); |
| 737 | sym = next_sym; |
| 738 | } |
| 739 | |
| 740 | insert_symbol_hashed (dict, sym); |
| 741 | } |
| 742 | } |
| 743 | |
| 744 | xfree (old_buckets); |
| 745 | } |
| 746 | |
| 747 | /* Functions for DICT_LINEAR and DICT_LINEAR_EXPANDABLE. */ |
| 748 | |
| 749 | static struct symbol * |
| 750 | iterator_first_linear (const struct dictionary *dict, |
| 751 | struct dict_iterator *iterator) |
| 752 | { |
| 753 | DICT_ITERATOR_DICT (iterator) = dict; |
| 754 | DICT_ITERATOR_INDEX (iterator) = 0; |
| 755 | return DICT_LINEAR_NSYMS (dict) ? DICT_LINEAR_SYM (dict, 0) : NULL; |
| 756 | } |
| 757 | |
| 758 | static struct symbol * |
| 759 | iterator_next_linear (struct dict_iterator *iterator) |
| 760 | { |
| 761 | const struct dictionary *dict = DICT_ITERATOR_DICT (iterator); |
| 762 | |
| 763 | if (++DICT_ITERATOR_INDEX (iterator) >= DICT_LINEAR_NSYMS (dict)) |
| 764 | return NULL; |
| 765 | else |
| 766 | return DICT_LINEAR_SYM (dict, DICT_ITERATOR_INDEX (iterator)); |
| 767 | } |
| 768 | |
| 769 | static struct symbol * |
| 770 | iter_name_first_linear (const struct dictionary *dict, |
| 771 | const char *name, |
| 772 | struct dict_iterator *iterator) |
| 773 | { |
| 774 | DICT_ITERATOR_DICT (iterator) = dict; |
| 775 | DICT_ITERATOR_INDEX (iterator) = -1; |
| 776 | |
| 777 | return iter_name_next_linear (name, iterator); |
| 778 | } |
| 779 | |
| 780 | static struct symbol * |
| 781 | iter_name_next_linear (const char *name, struct dict_iterator *iterator) |
| 782 | { |
| 783 | const struct dictionary *dict = DICT_ITERATOR_DICT (iterator); |
| 784 | int i, nsyms = DICT_LINEAR_NSYMS (dict); |
| 785 | struct symbol *sym, *retval = NULL; |
| 786 | |
| 787 | for (i = DICT_ITERATOR_INDEX (iterator) + 1; i < nsyms; ++i) |
| 788 | { |
| 789 | sym = DICT_LINEAR_SYM (dict, i); |
| 790 | if (strcmp_iw (SYMBOL_SEARCH_NAME (sym), name) == 0) |
| 791 | { |
| 792 | retval = sym; |
| 793 | break; |
| 794 | } |
| 795 | } |
| 796 | |
| 797 | DICT_ITERATOR_INDEX (iterator) = i; |
| 798 | |
| 799 | return retval; |
| 800 | } |
| 801 | |
| 802 | static int |
| 803 | size_linear (const struct dictionary *dict) |
| 804 | { |
| 805 | return DICT_LINEAR_NSYMS (dict); |
| 806 | } |
| 807 | |
| 808 | /* Functions only for DICT_LINEAR_EXPANDABLE. */ |
| 809 | |
| 810 | static void |
| 811 | free_linear_expandable (struct dictionary *dict) |
| 812 | { |
| 813 | xfree (DICT_LINEAR_SYMS (dict)); |
| 814 | xfree (dict); |
| 815 | } |
| 816 | |
| 817 | |
| 818 | static void |
| 819 | add_symbol_linear_expandable (struct dictionary *dict, |
| 820 | struct symbol *sym) |
| 821 | { |
| 822 | int nsyms = ++DICT_LINEAR_NSYMS (dict); |
| 823 | |
| 824 | /* Do we have enough room? If not, grow it. */ |
| 825 | if (nsyms > DICT_LINEAR_EXPANDABLE_CAPACITY (dict)) { |
| 826 | DICT_LINEAR_EXPANDABLE_CAPACITY (dict) *= 2; |
| 827 | DICT_LINEAR_SYMS (dict) |
| 828 | = xrealloc (DICT_LINEAR_SYMS (dict), |
| 829 | DICT_LINEAR_EXPANDABLE_CAPACITY (dict) |
| 830 | * sizeof (struct symbol *)); |
| 831 | } |
| 832 | |
| 833 | DICT_LINEAR_SYM (dict, nsyms - 1) = sym; |
| 834 | } |