xref: /PHP-8.1/Zend/zend_constants.c (revision fd1d5ec2)
1 /*
2    +----------------------------------------------------------------------+
3    | Zend Engine                                                          |
4    +----------------------------------------------------------------------+
5    | Copyright (c) Zend Technologies Ltd. (http://www.zend.com)           |
6    +----------------------------------------------------------------------+
7    | This source file is subject to version 2.00 of the Zend license,     |
8    | that is bundled with this package in the file LICENSE, and is        |
9    | available through the world-wide-web at the following url:           |
10    | http://www.zend.com/license/2_00.txt.                                |
11    | If you did not receive a copy of the Zend license and are unable to  |
12    | obtain it through the world-wide-web, please send a note to          |
13    | license@zend.com so we can mail you a copy immediately.              |
14    +----------------------------------------------------------------------+
15    | Authors: Andi Gutmans <andi@php.net>                                 |
16    |          Zeev Suraski <zeev@php.net>                                 |
17    +----------------------------------------------------------------------+
18 */
19 
20 #include "zend.h"
21 #include "zend_constants.h"
22 #include "zend_exceptions.h"
23 #include "zend_execute.h"
24 #include "zend_variables.h"
25 #include "zend_operators.h"
26 #include "zend_globals.h"
27 #include "zend_API.h"
28 
29 /* Protection from recursive self-referencing class constants */
30 #define IS_CONSTANT_VISITED_MARK    0x80
31 
32 #define IS_CONSTANT_VISITED(zv)     (Z_CONSTANT_FLAGS_P(zv) & IS_CONSTANT_VISITED_MARK)
33 #define MARK_CONSTANT_VISITED(zv)   Z_CONSTANT_FLAGS_P(zv) |= IS_CONSTANT_VISITED_MARK
34 #define RESET_CONSTANT_VISITED(zv)  Z_CONSTANT_FLAGS_P(zv) &= ~IS_CONSTANT_VISITED_MARK
35 
36 /* Use for special null/true/false constants. */
37 static zend_constant *null_const, *true_const, *false_const;
38 
free_zend_constant(zval * zv)39 void free_zend_constant(zval *zv)
40 {
41 	zend_constant *c = Z_PTR_P(zv);
42 
43 	if (!(ZEND_CONSTANT_FLAGS(c) & CONST_PERSISTENT)) {
44 		zval_ptr_dtor_nogc(&c->value);
45 		if (c->name) {
46 			zend_string_release_ex(c->name, 0);
47 		}
48 		efree(c);
49 	} else {
50 		zval_internal_ptr_dtor(&c->value);
51 		if (c->name) {
52 			zend_string_release_ex(c->name, 1);
53 		}
54 		free(c);
55 	}
56 }
57 
58 
59 #ifdef ZTS
copy_zend_constant(zval * zv)60 static void copy_zend_constant(zval *zv)
61 {
62 	zend_constant *c = Z_PTR_P(zv);
63 
64 	ZEND_ASSERT(ZEND_CONSTANT_FLAGS(c) & CONST_PERSISTENT);
65 	Z_PTR_P(zv) = pemalloc(sizeof(zend_constant), 1);
66 	memcpy(Z_PTR_P(zv), c, sizeof(zend_constant));
67 
68 	c = Z_PTR_P(zv);
69 	c->name = zend_string_copy(c->name);
70 	if (Z_TYPE(c->value) == IS_STRING) {
71 		Z_STR(c->value) = zend_string_dup(Z_STR(c->value), 1);
72 	}
73 }
74 
75 
zend_copy_constants(HashTable * target,HashTable * source)76 void zend_copy_constants(HashTable *target, HashTable *source)
77 {
78 	zend_hash_copy(target, source, copy_zend_constant);
79 }
80 #endif
81 
82 
clean_module_constant(zval * el,void * arg)83 static int clean_module_constant(zval *el, void *arg)
84 {
85 	zend_constant *c = (zend_constant *)Z_PTR_P(el);
86 	int module_number = *(int *)arg;
87 
88 	if (ZEND_CONSTANT_MODULE_NUMBER(c) == module_number) {
89 		return ZEND_HASH_APPLY_REMOVE;
90 	} else {
91 		return ZEND_HASH_APPLY_KEEP;
92 	}
93 }
94 
95 
clean_module_constants(int module_number)96 void clean_module_constants(int module_number)
97 {
98 	zend_hash_apply_with_argument(EG(zend_constants), clean_module_constant, (void *) &module_number);
99 }
100 
zend_startup_constants(void)101 void zend_startup_constants(void)
102 {
103 	EG(zend_constants) = (HashTable *) malloc(sizeof(HashTable));
104 	zend_hash_init(EG(zend_constants), 128, NULL, ZEND_CONSTANT_DTOR, 1);
105 }
106 
107 
108 
zend_register_standard_constants(void)109 void zend_register_standard_constants(void)
110 {
111 	REGISTER_MAIN_LONG_CONSTANT("E_ERROR", E_ERROR, CONST_PERSISTENT | CONST_CS);
112 	REGISTER_MAIN_LONG_CONSTANT("E_RECOVERABLE_ERROR", E_RECOVERABLE_ERROR, CONST_PERSISTENT | CONST_CS);
113 	REGISTER_MAIN_LONG_CONSTANT("E_WARNING", E_WARNING, CONST_PERSISTENT | CONST_CS);
114 	REGISTER_MAIN_LONG_CONSTANT("E_PARSE", E_PARSE, CONST_PERSISTENT | CONST_CS);
115 	REGISTER_MAIN_LONG_CONSTANT("E_NOTICE", E_NOTICE, CONST_PERSISTENT | CONST_CS);
116 	REGISTER_MAIN_LONG_CONSTANT("E_STRICT", E_STRICT, CONST_PERSISTENT | CONST_CS);
117 	REGISTER_MAIN_LONG_CONSTANT("E_DEPRECATED", E_DEPRECATED, CONST_PERSISTENT | CONST_CS);
118 	REGISTER_MAIN_LONG_CONSTANT("E_CORE_ERROR", E_CORE_ERROR, CONST_PERSISTENT | CONST_CS);
119 	REGISTER_MAIN_LONG_CONSTANT("E_CORE_WARNING", E_CORE_WARNING, CONST_PERSISTENT | CONST_CS);
120 	REGISTER_MAIN_LONG_CONSTANT("E_COMPILE_ERROR", E_COMPILE_ERROR, CONST_PERSISTENT | CONST_CS);
121 	REGISTER_MAIN_LONG_CONSTANT("E_COMPILE_WARNING", E_COMPILE_WARNING, CONST_PERSISTENT | CONST_CS);
122 	REGISTER_MAIN_LONG_CONSTANT("E_USER_ERROR", E_USER_ERROR, CONST_PERSISTENT | CONST_CS);
123 	REGISTER_MAIN_LONG_CONSTANT("E_USER_WARNING", E_USER_WARNING, CONST_PERSISTENT | CONST_CS);
124 	REGISTER_MAIN_LONG_CONSTANT("E_USER_NOTICE", E_USER_NOTICE, CONST_PERSISTENT | CONST_CS);
125 	REGISTER_MAIN_LONG_CONSTANT("E_USER_DEPRECATED", E_USER_DEPRECATED, CONST_PERSISTENT | CONST_CS);
126 
127 	REGISTER_MAIN_LONG_CONSTANT("E_ALL", E_ALL, CONST_PERSISTENT | CONST_CS);
128 
129 	REGISTER_MAIN_LONG_CONSTANT("DEBUG_BACKTRACE_PROVIDE_OBJECT", DEBUG_BACKTRACE_PROVIDE_OBJECT, CONST_PERSISTENT | CONST_CS);
130 	REGISTER_MAIN_LONG_CONSTANT("DEBUG_BACKTRACE_IGNORE_ARGS", DEBUG_BACKTRACE_IGNORE_ARGS, CONST_PERSISTENT | CONST_CS);
131 	REGISTER_MAIN_BOOL_CONSTANT("ZEND_THREAD_SAFE", ZTS_V, CONST_PERSISTENT | CONST_CS);
132 	REGISTER_MAIN_BOOL_CONSTANT("ZEND_DEBUG_BUILD", ZEND_DEBUG, CONST_PERSISTENT | CONST_CS);
133 
134 	/* Special constants true/false/null.  */
135 	REGISTER_MAIN_BOOL_CONSTANT("TRUE", 1, CONST_PERSISTENT);
136 	REGISTER_MAIN_BOOL_CONSTANT("FALSE", 0, CONST_PERSISTENT);
137 	REGISTER_MAIN_NULL_CONSTANT("NULL", CONST_PERSISTENT);
138 
139 	true_const = zend_hash_str_find_ptr(EG(zend_constants), "TRUE", sizeof("TRUE")-1);
140 	false_const = zend_hash_str_find_ptr(EG(zend_constants), "FALSE", sizeof("FALSE")-1);
141 	null_const = zend_hash_str_find_ptr(EG(zend_constants), "NULL", sizeof("NULL")-1);
142 }
143 
144 
zend_shutdown_constants(void)145 void zend_shutdown_constants(void)
146 {
147 	zend_hash_destroy(EG(zend_constants));
148 	free(EG(zend_constants));
149 }
150 
zend_register_null_constant(const char * name,size_t name_len,int flags,int module_number)151 ZEND_API void zend_register_null_constant(const char *name, size_t name_len, int flags, int module_number)
152 {
153 	zend_constant c;
154 
155 	ZVAL_NULL(&c.value);
156 	ZEND_CONSTANT_SET_FLAGS(&c, flags, module_number);
157 	c.name = zend_string_init_interned(name, name_len, flags & CONST_PERSISTENT);
158 	zend_register_constant(&c);
159 }
160 
zend_register_bool_constant(const char * name,size_t name_len,bool bval,int flags,int module_number)161 ZEND_API void zend_register_bool_constant(const char *name, size_t name_len, bool bval, int flags, int module_number)
162 {
163 	zend_constant c;
164 
165 	ZVAL_BOOL(&c.value, bval);
166 	ZEND_CONSTANT_SET_FLAGS(&c, flags, module_number);
167 	c.name = zend_string_init_interned(name, name_len, flags & CONST_PERSISTENT);
168 	zend_register_constant(&c);
169 }
170 
zend_register_long_constant(const char * name,size_t name_len,zend_long lval,int flags,int module_number)171 ZEND_API void zend_register_long_constant(const char *name, size_t name_len, zend_long lval, int flags, int module_number)
172 {
173 	zend_constant c;
174 
175 	ZVAL_LONG(&c.value, lval);
176 	ZEND_CONSTANT_SET_FLAGS(&c, flags, module_number);
177 	c.name = zend_string_init_interned(name, name_len, flags & CONST_PERSISTENT);
178 	zend_register_constant(&c);
179 }
180 
181 
zend_register_double_constant(const char * name,size_t name_len,double dval,int flags,int module_number)182 ZEND_API void zend_register_double_constant(const char *name, size_t name_len, double dval, int flags, int module_number)
183 {
184 	zend_constant c;
185 
186 	ZVAL_DOUBLE(&c.value, dval);
187 	ZEND_CONSTANT_SET_FLAGS(&c, flags, module_number);
188 	c.name = zend_string_init_interned(name, name_len, flags & CONST_PERSISTENT);
189 	zend_register_constant(&c);
190 }
191 
192 
zend_register_stringl_constant(const char * name,size_t name_len,const char * strval,size_t strlen,int flags,int module_number)193 ZEND_API void zend_register_stringl_constant(const char *name, size_t name_len, const char *strval, size_t strlen, int flags, int module_number)
194 {
195 	zend_constant c;
196 
197 	ZVAL_STR(&c.value, zend_string_init_interned(strval, strlen, flags & CONST_PERSISTENT));
198 	ZEND_CONSTANT_SET_FLAGS(&c, flags, module_number);
199 	c.name = zend_string_init_interned(name, name_len, flags & CONST_PERSISTENT);
200 	zend_register_constant(&c);
201 }
202 
203 
zend_register_string_constant(const char * name,size_t name_len,const char * strval,int flags,int module_number)204 ZEND_API void zend_register_string_constant(const char *name, size_t name_len, const char *strval, int flags, int module_number)
205 {
206 	zend_register_stringl_constant(name, name_len, strval, strlen(strval), flags, module_number);
207 }
208 
zend_get_halt_offset_constant(const char * name,size_t name_len)209 static zend_constant *zend_get_halt_offset_constant(const char *name, size_t name_len)
210 {
211 	zend_constant *c;
212 	static const char haltoff[] = "__COMPILER_HALT_OFFSET__";
213 
214 	if (!EG(current_execute_data)) {
215 		return NULL;
216 	} else if (name_len == sizeof("__COMPILER_HALT_OFFSET__")-1 &&
217 	          !memcmp(name, "__COMPILER_HALT_OFFSET__", sizeof("__COMPILER_HALT_OFFSET__")-1)) {
218 		const char *cfilename;
219 		zend_string *haltname;
220 		size_t clen;
221 
222 		cfilename = zend_get_executed_filename();
223 		clen = strlen(cfilename);
224 		/* check for __COMPILER_HALT_OFFSET__ */
225 		haltname = zend_mangle_property_name(haltoff,
226 			sizeof("__COMPILER_HALT_OFFSET__") - 1, cfilename, clen, 0);
227 		c = zend_hash_find_ptr(EG(zend_constants), haltname);
228 		zend_string_efree(haltname);
229 		return c;
230 	} else {
231 		return NULL;
232 	}
233 }
234 
_zend_get_special_const(const char * name,size_t len)235 ZEND_API zend_constant *_zend_get_special_const(const char *name, size_t len) /* {{{ */
236 {
237 	if (len == 4) {
238 		if ((name[0] == 'n' || name[0] == 'N') &&
239 			(name[1] == 'u' || name[1] == 'U') &&
240 			(name[2] == 'l' || name[2] == 'L') &&
241 			(name[3] == 'l' || name[3] == 'L')
242 		) {
243 			return null_const;
244 		}
245 		if ((name[0] == 't' || name[0] == 'T') &&
246 			(name[1] == 'r' || name[1] == 'R') &&
247 			(name[2] == 'u' || name[2] == 'U') &&
248 			(name[3] == 'e' || name[3] == 'E')
249 		) {
250 			return true_const;
251 		}
252 	} else {
253 		if ((name[0] == 'f' || name[0] == 'F') &&
254 			(name[1] == 'a' || name[1] == 'A') &&
255 			(name[2] == 'l' || name[2] == 'L') &&
256 			(name[3] == 's' || name[3] == 'S') &&
257 			(name[4] == 'e' || name[4] == 'E')
258 		) {
259 			return false_const;
260 		}
261 	}
262 	return NULL;
263 }
264 /* }}} */
265 
zend_verify_const_access(zend_class_constant * c,zend_class_entry * scope)266 ZEND_API bool zend_verify_const_access(zend_class_constant *c, zend_class_entry *scope) /* {{{ */
267 {
268 	if (ZEND_CLASS_CONST_FLAGS(c) & ZEND_ACC_PUBLIC) {
269 		return 1;
270 	} else if (ZEND_CLASS_CONST_FLAGS(c) & ZEND_ACC_PRIVATE) {
271 		return (c->ce == scope);
272 	} else {
273 		ZEND_ASSERT(ZEND_CLASS_CONST_FLAGS(c) & ZEND_ACC_PROTECTED);
274 		return zend_check_protected(c->ce, scope);
275 	}
276 }
277 /* }}} */
278 
zend_get_constant_str_impl(const char * name,size_t name_len)279 static zend_constant *zend_get_constant_str_impl(const char *name, size_t name_len)
280 {
281 	zend_constant *c = zend_hash_str_find_ptr(EG(zend_constants), name, name_len);
282 	if (c) {
283 		return c;
284 	}
285 
286 	c = zend_get_halt_offset_constant(name, name_len);
287 	if (c) {
288 		return c;
289 	}
290 
291 	return zend_get_special_const(name, name_len);
292 }
293 
zend_get_constant_str(const char * name,size_t name_len)294 ZEND_API zval *zend_get_constant_str(const char *name, size_t name_len)
295 {
296 	zend_constant *c = zend_get_constant_str_impl(name, name_len);
297 	if (c) {
298 		return &c->value;
299 	}
300 	return NULL;
301 }
302 
zend_get_constant_impl(zend_string * name)303 static zend_constant *zend_get_constant_impl(zend_string *name)
304 {
305 	zend_constant *c = zend_hash_find_ptr(EG(zend_constants), name);
306 	if (c) {
307 		return c;
308 	}
309 
310 	c = zend_get_halt_offset_constant(ZSTR_VAL(name), ZSTR_LEN(name));
311 	if (c) {
312 		return c;
313 	}
314 
315 	return zend_get_special_const(ZSTR_VAL(name), ZSTR_LEN(name));
316 }
317 
zend_get_constant(zend_string * name)318 ZEND_API zval *zend_get_constant(zend_string *name)
319 {
320 	zend_constant *c = zend_get_constant_impl(name);
321 	if (c) {
322 		return &c->value;
323 	}
324 	return NULL;
325 }
326 
zend_get_class_constant_ex(zend_string * class_name,zend_string * constant_name,zend_class_entry * scope,uint32_t flags)327 ZEND_API zval *zend_get_class_constant_ex(zend_string *class_name, zend_string *constant_name, zend_class_entry *scope, uint32_t flags)
328 {
329 	zend_class_entry *ce = NULL;
330 	zend_class_constant *c = NULL;
331 	zval *ret_constant = NULL;
332 
333 	if (ZSTR_HAS_CE_CACHE(class_name)) {
334 		ce = ZSTR_GET_CE_CACHE(class_name);
335 		if (!ce) {
336 			ce = zend_fetch_class(class_name, flags);
337 		}
338 	} else if (zend_string_equals_literal_ci(class_name, "self")) {
339 		if (UNEXPECTED(!scope)) {
340 			zend_throw_error(NULL, "Cannot access \"self\" when no class scope is active");
341 			goto failure;
342 		}
343 		ce = scope;
344 	} else if (zend_string_equals_literal_ci(class_name, "parent")) {
345 		if (UNEXPECTED(!scope)) {
346 			zend_throw_error(NULL, "Cannot access \"parent\" when no class scope is active");
347 			goto failure;
348 		} else if (UNEXPECTED(!scope->parent)) {
349 			zend_throw_error(NULL, "Cannot access \"parent\" when current class scope has no parent");
350 			goto failure;
351 		} else {
352 			ce = scope->parent;
353 		}
354 	} else if (zend_string_equals_literal_ci(class_name, "static")) {
355 		ce = zend_get_called_scope(EG(current_execute_data));
356 		if (UNEXPECTED(!ce)) {
357 			zend_throw_error(NULL, "Cannot access \"static\" when no class scope is active");
358 			goto failure;
359 		}
360 	} else {
361 		ce = zend_fetch_class(class_name, flags);
362 	}
363 	if (ce) {
364 		c = zend_hash_find_ptr(CE_CONSTANTS_TABLE(ce), constant_name);
365 		if (c == NULL) {
366 			if ((flags & ZEND_FETCH_CLASS_SILENT) == 0) {
367 				zend_throw_error(NULL, "Undefined constant %s::%s", ZSTR_VAL(class_name), ZSTR_VAL(constant_name));
368 				goto failure;
369 			}
370 			ret_constant = NULL;
371 		} else {
372 			if (!zend_verify_const_access(c, scope)) {
373 				if ((flags & ZEND_FETCH_CLASS_SILENT) == 0) {
374 					zend_throw_error(NULL, "Cannot access %s constant %s::%s", zend_visibility_string(ZEND_CLASS_CONST_FLAGS(c)), ZSTR_VAL(class_name), ZSTR_VAL(constant_name));
375 				}
376 				goto failure;
377 			}
378 			ret_constant = &c->value;
379 		}
380 	}
381 
382 	if (ret_constant && Z_TYPE_P(ret_constant) == IS_CONSTANT_AST) {
383 		zend_result ret;
384 
385 		if (IS_CONSTANT_VISITED(ret_constant)) {
386 			zend_throw_error(NULL, "Cannot declare self-referencing constant %s::%s", ZSTR_VAL(class_name), ZSTR_VAL(constant_name));
387 			ret_constant = NULL;
388 			goto failure;
389 		}
390 
391 		MARK_CONSTANT_VISITED(ret_constant);
392 		ret = zval_update_constant_ex(ret_constant, c->ce);
393 		RESET_CONSTANT_VISITED(ret_constant);
394 
395 		if (UNEXPECTED(ret != SUCCESS)) {
396 			ret_constant = NULL;
397 			goto failure;
398 		}
399 	}
400 failure:
401 	return ret_constant;
402 }
403 
zend_get_constant_ex(zend_string * cname,zend_class_entry * scope,uint32_t flags)404 ZEND_API zval *zend_get_constant_ex(zend_string *cname, zend_class_entry *scope, uint32_t flags)
405 {
406 	zend_constant *c;
407 	const char *colon;
408 	const char *name = ZSTR_VAL(cname);
409 	size_t name_len = ZSTR_LEN(cname);
410 
411 	/* Skip leading \\ */
412 	if (name[0] == '\\') {
413 		name += 1;
414 		name_len -= 1;
415 		cname = NULL;
416 	}
417 
418 	if ((colon = zend_memrchr(name, ':', name_len)) &&
419 	    colon > name && (*(colon - 1) == ':')) {
420 		int class_name_len = colon - name - 1;
421 		size_t const_name_len = name_len - class_name_len - 2;
422 		zend_string *constant_name = zend_string_init(colon + 1, const_name_len, 0);
423 		zend_string *class_name = zend_string_init_interned(name, class_name_len, 0);
424 		zval *ret_constant = zend_get_class_constant_ex(class_name, constant_name, scope, flags);
425 
426 		zend_string_release_ex(class_name, 0);
427 		zend_string_efree(constant_name);
428 		return ret_constant;
429 /*
430 		zend_class_entry *ce = NULL;
431 		zend_class_constant *c = NULL;
432 		zval *ret_constant = NULL;
433 
434 		if (zend_string_equals_literal_ci(class_name, "self")) {
435 			if (UNEXPECTED(!scope)) {
436 				zend_throw_error(NULL, "Cannot access \"self\" when no class scope is active");
437 				goto failure;
438 			}
439 			ce = scope;
440 		} else if (zend_string_equals_literal_ci(class_name, "parent")) {
441 			if (UNEXPECTED(!scope)) {
442 				zend_throw_error(NULL, "Cannot access \"parent\" when no class scope is active");
443 				goto failure;
444 			} else if (UNEXPECTED(!scope->parent)) {
445 				zend_throw_error(NULL, "Cannot access \"parent\" when current class scope has no parent");
446 				goto failure;
447 			} else {
448 				ce = scope->parent;
449 			}
450 		} else if (zend_string_equals_literal_ci(class_name, "static")) {
451 			ce = zend_get_called_scope(EG(current_execute_data));
452 			if (UNEXPECTED(!ce)) {
453 				zend_throw_error(NULL, "Cannot access \"static\" when no class scope is active");
454 				goto failure;
455 			}
456 		} else {
457 			ce = zend_fetch_class(class_name, flags);
458 		}
459 		if (ce) {
460 			c = zend_hash_find_ptr(CE_CONSTANTS_TABLE(ce), constant_name);
461 			if (c == NULL) {
462 				if ((flags & ZEND_FETCH_CLASS_SILENT) == 0) {
463 					zend_throw_error(NULL, "Undefined constant %s::%s", ZSTR_VAL(class_name), ZSTR_VAL(constant_name));
464 					goto failure;
465 				}
466 				ret_constant = NULL;
467 			} else {
468 				if (!zend_verify_const_access(c, scope)) {
469 					if ((flags & ZEND_FETCH_CLASS_SILENT) == 0) {
470 						zend_throw_error(NULL, "Cannot access %s constant %s::%s", zend_visibility_string(ZEND_CLASS_CONST_FLAGS(c)), ZSTR_VAL(class_name), ZSTR_VAL(constant_name));
471 					}
472 					goto failure;
473 				}
474 				ret_constant = &c->value;
475 			}
476 		}
477 
478 		if (ret_constant && Z_TYPE_P(ret_constant) == IS_CONSTANT_AST) {
479 			zend_result ret;
480 
481 			if (IS_CONSTANT_VISITED(ret_constant)) {
482 				zend_throw_error(NULL, "Cannot declare self-referencing constant %s::%s", ZSTR_VAL(class_name), ZSTR_VAL(constant_name));
483 				ret_constant = NULL;
484 				goto failure;
485 			}
486 
487 			MARK_CONSTANT_VISITED(ret_constant);
488 			ret = zval_update_constant_ex(ret_constant, c->ce);
489 			RESET_CONSTANT_VISITED(ret_constant);
490 
491 			if (UNEXPECTED(ret != SUCCESS)) {
492 				ret_constant = NULL;
493 				goto failure;
494 			}
495 		}
496 failure:
497 		zend_string_release_ex(class_name, 0);
498 		zend_string_efree(constant_name);
499 		return ret_constant;
500 */
501 	}
502 
503 	/* non-class constant */
504 	if ((colon = zend_memrchr(name, '\\', name_len)) != NULL) {
505 		/* compound constant name */
506 		int prefix_len = colon - name;
507 		size_t const_name_len = name_len - prefix_len - 1;
508 		const char *constant_name = colon + 1;
509 		char *lcname;
510 		size_t lcname_len;
511 		ALLOCA_FLAG(use_heap)
512 
513 		/* Lowercase the namespace portion */
514 		lcname_len = prefix_len + 1 + const_name_len;
515 		lcname = do_alloca(lcname_len + 1, use_heap);
516 		zend_str_tolower_copy(lcname, name, prefix_len);
517 
518 		lcname[prefix_len] = '\\';
519 		memcpy(lcname + prefix_len + 1, constant_name, const_name_len + 1);
520 
521 		c = zend_hash_str_find_ptr(EG(zend_constants), lcname, lcname_len);
522 		free_alloca(lcname, use_heap);
523 
524 		if (!c) {
525 			if (flags & IS_CONSTANT_UNQUALIFIED_IN_NAMESPACE) {
526 				/* name requires runtime resolution, need to check non-namespaced name */
527 				c = zend_get_constant_str_impl(constant_name, const_name_len);
528 			}
529 		}
530 	} else {
531 		if (cname) {
532 			c = zend_get_constant_impl(cname);
533 		} else {
534 			c = zend_get_constant_str_impl(name, name_len);
535 		}
536 	}
537 
538 	if (!c) {
539 		if (!(flags & ZEND_FETCH_CLASS_SILENT)) {
540 			zend_throw_error(NULL, "Undefined constant \"%s\"", name);
541 		}
542 		return NULL;
543 	}
544 
545 	if (!(flags & ZEND_FETCH_CLASS_SILENT) && (ZEND_CONSTANT_FLAGS(c) & CONST_DEPRECATED)) {
546 		zend_error(E_DEPRECATED, "Constant %s is deprecated", name);
547 	}
548 	return &c->value;
549 }
550 
zend_hash_add_constant(HashTable * ht,zend_string * key,zend_constant * c)551 static void* zend_hash_add_constant(HashTable *ht, zend_string *key, zend_constant *c)
552 {
553 	void *ret;
554 	zend_constant *copy = pemalloc(sizeof(zend_constant), ZEND_CONSTANT_FLAGS(c) & CONST_PERSISTENT);
555 
556 	memcpy(copy, c, sizeof(zend_constant));
557 	ret = zend_hash_add_ptr(ht, key, copy);
558 	if (!ret) {
559 		pefree(copy, ZEND_CONSTANT_FLAGS(c) & CONST_PERSISTENT);
560 	}
561 	return ret;
562 }
563 
zend_register_constant(zend_constant * c)564 ZEND_API zend_result zend_register_constant(zend_constant *c)
565 {
566 	zend_string *lowercase_name = NULL;
567 	zend_string *name;
568 	zend_result ret = SUCCESS;
569 	bool persistent = (ZEND_CONSTANT_FLAGS(c) & CONST_PERSISTENT) != 0;
570 
571 #if 0
572 	printf("Registering constant for module %d\n", c->module_number);
573 #endif
574 
575 	const char *slash = strrchr(ZSTR_VAL(c->name), '\\');
576 	if (slash) {
577 		lowercase_name = zend_string_init(ZSTR_VAL(c->name), ZSTR_LEN(c->name), persistent);
578 		zend_str_tolower(ZSTR_VAL(lowercase_name), slash - ZSTR_VAL(c->name));
579 		lowercase_name = zend_new_interned_string(lowercase_name);
580 		name = lowercase_name;
581 	} else {
582 		name = c->name;
583 	}
584 
585 	/* Check if the user is trying to define any special constant */
586 	if (zend_string_equals_literal(name, "__COMPILER_HALT_OFFSET__")
587 		|| (!persistent && zend_get_special_const(ZSTR_VAL(name), ZSTR_LEN(name)))
588 		|| zend_hash_add_constant(EG(zend_constants), name, c) == NULL
589 	) {
590 		zend_error(E_WARNING, "Constant %s already defined", ZSTR_VAL(name));
591 		zend_string_release(c->name);
592 		if (!persistent) {
593 			zval_ptr_dtor_nogc(&c->value);
594 		}
595 		ret = FAILURE;
596 	}
597 	if (lowercase_name) {
598 		zend_string_release(lowercase_name);
599 	}
600 	return ret;
601 }
602