GeezerVisonThe World Wide Web, restored to 800 pixels of glory. |
| Home|About|Gaming cabinet|Archives|How it works|Starter sites |
GeezerVison is showing github.com — stepcode/src/express/entity.c at develop · stepcode/stepcode Expand file tree/ Copy pathentity.cMore file actions 491 lines (447 loc) · 14.2 KB / Copy pathentity.cFile metadata and controls491 lines (447 loc) · 14.2 KB 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 /** ** Module: Entity \file entity.c * ** This module is used to represent Express entity definitions. ** An entity definition consists of a name, a set of attributes, a ** collection of uniqueness sets, a specification of the entity's ** position in a class hierarchy (i.e., sub- and supertypes), and ** a list of constraints which must be satisfied by instances of ** the entity. A uniquess set is a set of one or more attributes ** which, when taken together, uniquely identify a specific instance ** of the entity. Thus, the uniqueness set { name, ssn } indicates ** that no two instances of the entity may share both the same ** values for both name and ssn. * ** Constants: ** ENTITY_NULL - the null entity ** ************************************************************************/ /* * This software was developed by U.S. Government employees as part of * their official duties and is not subject to copyright. * * $Log: entity.c,v $ * Revision 1.11 1997/01/21 19:19:51 dar * made C++ compatible * * Revision 1.10 1995/03/09 18:43:03 clark * various fixes for caddetc - before interface clause changes * * Revision 1.9 1994/11/10 19:20:03 clark * Update to IS * * Revision 1.8 1993/10/15 18:48:48 libes * CADDETC certified * * Revision 1.6 1993/02/16 03:14:47 libes * simplified find calls * * Revision 1.5 1993/01/19 22:45:07 libes * *** empty log message *** * * Revision 1.4 1992/08/18 17:13:43 libes * rm'd extraneous error messages * * Revision 1.3 1992/06/08 18:06:57 libes * prettied up interface to print_objects_when_running * * Revision 1.2 1992/05/31 08:35:51 libes * multiple files * * Revision 1.1 1992/05/28 03:55:04 libes * Initial revision * * Revision 1.7 1992/05/10 06:01:29 libes * cleaned up OBJget_symbol * * Revision 1.6 1992/05/05 19:51:47 libes * final alpha * * Revision 1.5 1992/02/19 15:48:18 libes * changed types to enums & flags * * Revision 1.4 1992/02/17 14:32:57 libes * lazy ref/use evaluation now working * * Revision 1.3 1992/02/12 07:05:23 libes * y * do sub/supertype * * Revision 1.2 1992/02/09 00:49:53 libes * does ref/use correctly * * Revision 1.1 1992/02/05 08:34:24 libes * Initial revision * * Revision 1.0.1.1 1992/01/22 02:47:57 libes * copied from ~pdes * * Revision 4.7 1991/09/20 06:20:43 libes * fixed bug that printed out entity->attributes incorrectly * assumed they were objects rather than strings * * Revision 4.6 1991/09/16 23:13:12 libes * added print functionsalgorithm.c * * Revision 4.5 1991/07/18 05:07:08 libes * added SCOPEget_use * * Revision 4.4 1991/07/13 05:04:17 libes * added ENTITYget_supertype and ..get_subtype * * Revision 4.3 1991/01/24 22:20:36 silver * merged changes from NIST and SCRA * SCRA changes are due to DEC ANSI C compiler tests. * * Revision 4.3 91/01/08 18:55:42 pdesadmn * Initial - Beta checkin at SCRA * * Revision 4.2 90/11/23 16:33:43 clark * Initial checkin at SCRA * * Revision 4.2 90/11/23 16:33:43 clark * initial checkin at SCRA * * Revision 4.2 90/11/23 16:33:43 clark * Fixes for better error handling on supertype lists * * Revision 4.1 90/09/13 15:13:08 clark * BPR 2.1 alpha * */ #include "express/entity.h" #include "express/express.h" #include "express/object.h" int ENTITY_MARK = 0; /** returns true if variable is declared (or redeclared) directly by entity */ int ENTITYdeclares_variable( Entity e, Variable v ) { LISTdo( e->u.entity->attributes, attr, Variable ) if( attr == v ) { return true; } LISTod; return false; } static Entity ENTITY_find_inherited_entity( Entity entity, char * name, int down ) { Entity result; /* avoid searching scopes that we've already searched */ /* this can happen due to several things */ /* if A ref's B which ref's C, and A ref's C. Then C */ /* can be searched twice by A. Similar problem with */ /* sub/super inheritance. */ if( entity->search_id == __SCOPE_search_id ) { return NULL; } entity->search_id = __SCOPE_search_id; LISTdo( entity->u.entity->supertypes, super, Entity ) if( !strcmp( super->symbol.name, name ) ) { return super; } LISTod LISTdo( entity->u.entity->supertypes, super, Entity ) result = ENTITY_find_inherited_entity( super, name, down ); if( result ) { return result; } LISTod; if( down ) { LISTdo( entity->u.entity->subtypes, sub, Entity ) if( !strcmp( sub->symbol.name, name ) ) { return sub; } LISTod; LISTdo( entity->u.entity->subtypes, sub, Entity ) result = ENTITY_find_inherited_entity( sub, name, down ); if( result ) { return result; } LISTod; } return 0; } struct Scope_ * ENTITYfind_inherited_entity( struct Scope_ *entity, char * name, int down ) { if( !strcmp( name, entity->symbol.name ) ) { return( entity ); } __SCOPE_search_id++; return ENTITY_find_inherited_entity( entity, name, down ); } /** find a (possibly inherited) attribute */ Variable ENTITY_find_inherited_attribute( Entity entity, char * name, int * down, struct Symbol_ ** where ) { Variable result; /* avoid searching scopes that we've already searched */ /* this can happen due to several things */ /* if A ref's B which ref's C, and A ref's C. Then C */ /* can be searched twice by A. Similar problem with */ /* sub/super inheritance. */ if( entity->search_id == __SCOPE_search_id ) { return NULL; } entity->search_id = __SCOPE_search_id; /* first look locally */ result = ( Variable )DICTlookup( entity->symbol_table, name ); if( result ) { if( down && *down && where ) { *where = &entity->symbol; } return result; } /* check supertypes */ LISTdo( entity->u.entity->supertypes, super, Entity ) result = ENTITY_find_inherited_attribute( super, name, down, where ); if( result ) { return result; } LISTod; /* check subtypes, if requested */ if( down ) { ++*down; LISTdo( entity->u.entity->subtypes, sub, Entity ) result = ENTITY_find_inherited_attribute( sub, name, down, where ); if( result ) { return result; } LISTod; --*down; } return 0; } Variable ENTITYfind_inherited_attribute( struct Scope_ *entity, char * name, struct Symbol_ ** down_sym ) { extern int __SCOPE_search_id; int down_flag = 0; __SCOPE_search_id++; if( down_sym ) { return ENTITY_find_inherited_attribute( entity, name, &down_flag, down_sym ); } else { return ENTITY_find_inherited_attribute( entity, name, 0, 0 ); } } /** resolve a (possibly group-qualified) attribute ref. * report errors as appropriate */ Variable ENTITYresolve_attr_ref( Entity e, Symbol * grp_ref, Symbol * attr_ref ) { Entity ref_entity; Variable attr; struct Symbol_ *where; if( grp_ref ) { /* use entity provided in group reference */ ref_entity = ENTITYfind_inherited_entity( e, grp_ref->name, 0 ); if( !ref_entity ) { ERRORreport_with_symbol(UNKNOWN_SUPERTYPE, grp_ref, grp_ref->name, e->symbol.name ); return 0; } attr = ( Variable )DICTlookup( ref_entity->symbol_table, attr_ref->name ); if( !attr ) { ERRORreport_with_symbol(UNKNOWN_ATTR_IN_ENTITY, attr_ref, attr_ref->name, ref_entity->symbol.name ); /* resolve_failed(e);*/ } } else { /* no entity provided, look through supertype chain */ where = NULL; attr = ENTITYfind_inherited_attribute( e, attr_ref->name, &where ); if( !attr /* was ref_entity? */ ) { ERRORreport_with_symbol(UNKNOWN_ATTR_IN_ENTITY, attr_ref, attr_ref->name, e->symbol.name ); } else if( where != NULL ) { ERRORreport_with_symbol(IMPLICIT_DOWNCAST, attr_ref, where->name ); } } return attr; } /** * currently, this is only used by USEresolve * low-level function for type Entity */ Entity ENTITYcopy( Entity e ) { /* for now, do a totally shallow copy */ Entity e2 = SCOPE_new(); *e2 = *e; return e2; } /** Initialize the Entity module. */ void ENTITYinitialize(void) { } /** ** \param entity entity to modify ** \param attr attribute to add ** Add an attribute to an entity. */ void ENTITYadd_attribute( Entity entity, Variable attr ) { int rc; if( attr->name->type->u.type->body->type != op_ ) { /* simple id */ rc = DICTdefine( entity->symbol_table, attr->name->symbol.name, attr, &attr->name->symbol, OBJ_VARIABLE ); } else { /* SELF\ENTITY.SIMPLE_ID */ rc = DICTdefine( entity->symbol_table, attr->name->e.op2->symbol.name, attr, &attr->name->symbol, OBJ_VARIABLE ); } if( rc == 0 ) { LISTadd_last( entity->u.entity->attributes, attr ); VARput_offset( attr, entity->u.entity->attribute_count ); entity->u.entity->attribute_count++; } } /** ** \param entity entity to modify ** \param instance new instance ** Add an item to the instance list of an entity. */ void ENTITYadd_instance( Entity entity, void *instance ) { if( entity->u.entity->instances == LIST_NULL ) { entity->u.entity->instances = LISTcreate(); } LISTadd_last( entity->u.entity->instances, instance ); } /** ** \param child entity to check parentage of ** \param parent parent to check for ** \return does child's superclass chain include parent? ** Look for a certain entity in the supertype graph of an entity. */ bool ENTITYhas_supertype( Entity child, Entity parent ) { LISTdo( child->u.entity->supertypes, entity, Entity ) if( entity == parent ) { return true; } if( ENTITYhas_supertype( entity, parent ) ) { return true; } LISTod; return false; } /** ** \param child entity to check parentage of ** \param parent parent to check for ** \return is parent a direct supertype of child? ** Check whether an entity has a specific immediate superclass. */ bool ENTITYhas_immediate_supertype( Entity child, Entity parent ) { LISTdo( child->u.entity->supertypes, entity, Entity ) if( entity == parent ) { return true; } LISTod; return false; } /** called by ENTITYget_all_attributes(). \sa ENTITYget_all_attributes */ static void ENTITY_get_all_attributes( Entity entity, Linked_List result ) { LISTdo( entity->u.entity->supertypes, super, Entity ) /* if (OBJis_kind_of(super, Class_Entity))*/ ENTITY_get_all_attributes( super, result ); LISTod; /* Gee, aren't they resolved by this time? */ LISTdo( entity->u.entity->attributes, attr, void * ) LISTadd_last( result, attr ); LISTod; } /** ** \param entity - entity to examine ** \return all attributes of this entity ** ** Retrieve the attribute list of an entity. ** \sa ENTITY_get_all_attributes() ** ** \note If an entity has neither defines nor inherits any ** attributes, this call returns an empty list. Note ** that this is distinct from the constant LIST_NULL. */ Linked_List ENTITYget_all_attributes( Entity entity ) { Linked_List result = LISTcreate(); ENTITY_get_all_attributes( entity, result ); return result; } /** ** \param entity - entity to examine ** \param name - name of attribute to retrieve ** \return the named attribute of this entity ** Retrieve an entity attribute by name. ** ** \note If the entity has no attribute with the given name, ** VARIABLE_NULL is returned. */ Variable ENTITYget_named_attribute( Entity entity, char * name ) { Variable attribute; LISTdo( entity->u.entity->attributes, attr, Variable ) if( !strcmp( VARget_simple_name( attr ), name ) ) { return attr; } LISTod; LISTdo( entity->u.entity->supertypes, super, Entity ) /* if (OBJis_kind_of(super, Class_Entity) && */ if( 0 != ( attribute = ENTITYget_named_attribute( super, name ) ) ) { return attribute; } LISTod; return 0; } /** ** \param entity entity to examine ** \param attribute attribute to retrieve offset for ** \return offset to given attribute ** Retrieve offset to an entity attribute. ** ** \note If the entity does not include the attribute, -1 ** is returned. */ int ENTITYget_attribute_offset( Entity entity, Variable attribute ) { int offset; int value; LISTdo( entity->u.entity->attributes, attr, Variable ) if( attr == attribute ) { return entity->u.entity->inheritance + VARget_offset( attribute ); } LISTod; offset = 0; LISTdo( entity->u.entity->supertypes, super, Entity ) /* if (OBJis_kind_of(super, Class_Entity)) {*/ if( ( value = ENTITYget_attribute_offset( super, attribute ) ) != -1 ) { return value + offset; } offset += ENTITYget_initial_offset( super ); /* }*/ LISTod; return -1; } /** ** \param entity entity to examine ** \param name name of attribute to retrieve ** \return offset to named attribute of this entity ** Retrieve offset to an entity attribute by name. ** ** \note If the entity has no attribute with the given name, ** -1 is returned. */ int ENTITYget_named_attribute_offset( Entity entity, char * name ) { int offset; int value; LISTdo( entity->u.entity->attributes, attr, Variable ) if( !strcmp( VARget_simple_name( attr ), name ) ) return entity->u.entity->inheritance + VARget_offset( ENTITY_find_inherited_attribute( entity, name, 0, 0 ) ); LISTod; offset = 0; LISTdo( entity->u.entity->supertypes, super, Entity ) /* if (OBJis_kind_of(super, Class_Entity)) {*/ if( ( value = ENTITYget_named_attribute_offset( super, name ) ) != -1 ) { return value + offset; } offset += ENTITYget_initial_offset( super ); /* }*/ LISTod; return -1; } /** ** \param entity entity to examine ** \return number of inherited attributes ** Retrieve the initial offset to an entity's local frame. */ int ENTITYget_initial_offset( Entity entity ) { return entity->u.entity->inheritance; } |
| You are visitor 01402520 — GeezerVison does not store the pages you look up. Best viewed with Netscape Navigator 4.7 or Internet Explorer 6 at 800×600. No cookies required. |