php-src/Zend/zend_constants.c
2023-07-17 22:32:41 +02:00

594 lines
18 KiB
C

/*
+----------------------------------------------------------------------+
| Zend Engine |
+----------------------------------------------------------------------+
| Copyright (c) Zend Technologies Ltd. (http://www.zend.com) |
+----------------------------------------------------------------------+
| This source file is subject to version 2.00 of the Zend license, |
| that is bundled with this package in the file LICENSE, and is |
| available through the world-wide-web at the following url: |
| http://www.zend.com/license/2_00.txt. |
| If you did not receive a copy of the Zend license and are unable to |
| obtain it through the world-wide-web, please send a note to |
| license@zend.com so we can mail you a copy immediately. |
+----------------------------------------------------------------------+
| Authors: Andi Gutmans <andi@php.net> |
| Zeev Suraski <zeev@php.net> |
+----------------------------------------------------------------------+
*/
#include "zend.h"
#include "zend_constants.h"
#include "zend_exceptions.h"
#include "zend_execute.h"
#include "zend_variables.h"
#include "zend_operators.h"
#include "zend_globals.h"
#include "zend_API.h"
#include "zend_constants_arginfo.h"
/* Protection from recursive self-referencing class constants */
#define IS_CONSTANT_VISITED_MARK 0x80
#define IS_CONSTANT_VISITED(zv) (Z_CONSTANT_FLAGS_P(zv) & IS_CONSTANT_VISITED_MARK)
#define MARK_CONSTANT_VISITED(zv) Z_CONSTANT_FLAGS_P(zv) |= IS_CONSTANT_VISITED_MARK
#define RESET_CONSTANT_VISITED(zv) Z_CONSTANT_FLAGS_P(zv) &= ~IS_CONSTANT_VISITED_MARK
/* Use for special null/true/false constants. */
static zend_constant *null_const, *true_const, *false_const;
void free_zend_constant(zval *zv)
{
zend_constant *c = Z_PTR_P(zv);
if (!(ZEND_CONSTANT_FLAGS(c) & CONST_PERSISTENT)) {
zval_ptr_dtor_nogc(&c->value);
if (c->name) {
zend_string_release_ex(c->name, 0);
}
efree(c);
} else {
zval_internal_ptr_dtor(&c->value);
if (c->name) {
zend_string_release_ex(c->name, 1);
}
free(c);
}
}
#ifdef ZTS
static void copy_zend_constant(zval *zv)
{
zend_constant *c = Z_PTR_P(zv);
ZEND_ASSERT(ZEND_CONSTANT_FLAGS(c) & CONST_PERSISTENT);
Z_PTR_P(zv) = pemalloc(sizeof(zend_constant), 1);
memcpy(Z_PTR_P(zv), c, sizeof(zend_constant));
c = Z_PTR_P(zv);
c->name = zend_string_copy(c->name);
if (Z_TYPE(c->value) == IS_STRING) {
Z_STR(c->value) = zend_string_dup(Z_STR(c->value), 1);
}
}
void zend_copy_constants(HashTable *target, HashTable *source)
{
zend_hash_copy(target, source, copy_zend_constant);
}
#endif
static int clean_module_constant(zval *el, void *arg)
{
zend_constant *c = (zend_constant *)Z_PTR_P(el);
int module_number = *(int *)arg;
if (ZEND_CONSTANT_MODULE_NUMBER(c) == module_number) {
return ZEND_HASH_APPLY_REMOVE;
} else {
return ZEND_HASH_APPLY_KEEP;
}
}
void clean_module_constants(int module_number)
{
zend_hash_apply_with_argument(EG(zend_constants), clean_module_constant, (void *) &module_number);
}
void zend_startup_constants(void)
{
EG(zend_constants) = (HashTable *) malloc(sizeof(HashTable));
zend_hash_init(EG(zend_constants), 128, NULL, ZEND_CONSTANT_DTOR, 1);
}
void zend_register_standard_constants(void)
{
register_zend_constants_symbols(0);
true_const = zend_hash_str_find_ptr(EG(zend_constants), "TRUE", sizeof("TRUE")-1);
false_const = zend_hash_str_find_ptr(EG(zend_constants), "FALSE", sizeof("FALSE")-1);
null_const = zend_hash_str_find_ptr(EG(zend_constants), "NULL", sizeof("NULL")-1);
}
void zend_shutdown_constants(void)
{
zend_hash_destroy(EG(zend_constants));
free(EG(zend_constants));
}
ZEND_API void zend_register_null_constant(const char *name, size_t name_len, int flags, int module_number)
{
zend_constant c;
ZVAL_NULL(&c.value);
ZEND_CONSTANT_SET_FLAGS(&c, flags, module_number);
c.name = zend_string_init_interned(name, name_len, flags & CONST_PERSISTENT);
zend_register_constant(&c);
}
ZEND_API void zend_register_bool_constant(const char *name, size_t name_len, bool bval, int flags, int module_number)
{
zend_constant c;
ZVAL_BOOL(&c.value, bval);
ZEND_CONSTANT_SET_FLAGS(&c, flags, module_number);
c.name = zend_string_init_interned(name, name_len, flags & CONST_PERSISTENT);
zend_register_constant(&c);
}
ZEND_API void zend_register_long_constant(const char *name, size_t name_len, zend_long lval, int flags, int module_number)
{
zend_constant c;
ZVAL_LONG(&c.value, lval);
ZEND_CONSTANT_SET_FLAGS(&c, flags, module_number);
c.name = zend_string_init_interned(name, name_len, flags & CONST_PERSISTENT);
zend_register_constant(&c);
}
ZEND_API void zend_register_double_constant(const char *name, size_t name_len, double dval, int flags, int module_number)
{
zend_constant c;
ZVAL_DOUBLE(&c.value, dval);
ZEND_CONSTANT_SET_FLAGS(&c, flags, module_number);
c.name = zend_string_init_interned(name, name_len, flags & CONST_PERSISTENT);
zend_register_constant(&c);
}
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)
{
zend_constant c;
ZVAL_STR(&c.value, zend_string_init_interned(strval, strlen, flags & CONST_PERSISTENT));
ZEND_CONSTANT_SET_FLAGS(&c, flags, module_number);
c.name = zend_string_init_interned(name, name_len, flags & CONST_PERSISTENT);
zend_register_constant(&c);
}
ZEND_API void zend_register_string_constant(const char *name, size_t name_len, const char *strval, int flags, int module_number)
{
zend_register_stringl_constant(name, name_len, strval, strlen(strval), flags, module_number);
}
static zend_constant *zend_get_halt_offset_constant(const char *name, size_t name_len)
{
zend_constant *c;
static const char haltoff[] = "__COMPILER_HALT_OFFSET__";
if (!EG(current_execute_data)) {
return NULL;
} else if (name_len == sizeof("__COMPILER_HALT_OFFSET__")-1 &&
!memcmp(name, "__COMPILER_HALT_OFFSET__", sizeof("__COMPILER_HALT_OFFSET__")-1)) {
const char *cfilename;
zend_string *haltname;
size_t clen;
cfilename = zend_get_executed_filename();
clen = strlen(cfilename);
/* check for __COMPILER_HALT_OFFSET__ */
haltname = zend_mangle_property_name(haltoff,
sizeof("__COMPILER_HALT_OFFSET__") - 1, cfilename, clen, 0);
c = zend_hash_find_ptr(EG(zend_constants), haltname);
zend_string_efree(haltname);
return c;
} else {
return NULL;
}
}
ZEND_API zend_constant *_zend_get_special_const(const char *name, size_t len) /* {{{ */
{
if (len == 4) {
if ((name[0] == 'n' || name[0] == 'N') &&
(name[1] == 'u' || name[1] == 'U') &&
(name[2] == 'l' || name[2] == 'L') &&
(name[3] == 'l' || name[3] == 'L')
) {
return null_const;
}
if ((name[0] == 't' || name[0] == 'T') &&
(name[1] == 'r' || name[1] == 'R') &&
(name[2] == 'u' || name[2] == 'U') &&
(name[3] == 'e' || name[3] == 'E')
) {
return true_const;
}
} else {
if ((name[0] == 'f' || name[0] == 'F') &&
(name[1] == 'a' || name[1] == 'A') &&
(name[2] == 'l' || name[2] == 'L') &&
(name[3] == 's' || name[3] == 'S') &&
(name[4] == 'e' || name[4] == 'E')
) {
return false_const;
}
}
return NULL;
}
/* }}} */
ZEND_API bool zend_verify_const_access(zend_class_constant *c, zend_class_entry *scope) /* {{{ */
{
if (ZEND_CLASS_CONST_FLAGS(c) & ZEND_ACC_PUBLIC) {
return 1;
} else if (ZEND_CLASS_CONST_FLAGS(c) & ZEND_ACC_PRIVATE) {
return (c->ce == scope);
} else {
ZEND_ASSERT(ZEND_CLASS_CONST_FLAGS(c) & ZEND_ACC_PROTECTED);
return zend_check_protected(c->ce, scope);
}
}
/* }}} */
static zend_constant *zend_get_constant_str_impl(const char *name, size_t name_len)
{
zend_constant *c = zend_hash_str_find_ptr(EG(zend_constants), name, name_len);
if (c) {
return c;
}
c = zend_get_halt_offset_constant(name, name_len);
if (c) {
return c;
}
return zend_get_special_const(name, name_len);
}
ZEND_API zval *zend_get_constant_str(const char *name, size_t name_len)
{
zend_constant *c = zend_get_constant_str_impl(name, name_len);
if (c) {
return &c->value;
}
return NULL;
}
static zend_constant *zend_get_constant_impl(zend_string *name)
{
zend_constant *c = zend_hash_find_ptr(EG(zend_constants), name);
if (c) {
return c;
}
c = zend_get_halt_offset_constant(ZSTR_VAL(name), ZSTR_LEN(name));
if (c) {
return c;
}
return zend_get_special_const(ZSTR_VAL(name), ZSTR_LEN(name));
}
ZEND_API zval *zend_get_constant(zend_string *name)
{
zend_constant *c = zend_get_constant_impl(name);
if (c) {
return &c->value;
}
return NULL;
}
ZEND_API zval *zend_get_class_constant_ex(zend_string *class_name, zend_string *constant_name, zend_class_entry *scope, uint32_t flags)
{
zend_class_entry *ce = NULL;
zend_class_constant *c = NULL;
zval *ret_constant = NULL;
if (ZSTR_HAS_CE_CACHE(class_name)) {
ce = ZSTR_GET_CE_CACHE(class_name);
if (!ce) {
ce = zend_fetch_class(class_name, flags);
}
} else if (zend_string_equals_literal_ci(class_name, "self")) {
if (UNEXPECTED(!scope)) {
zend_throw_error(NULL, "Cannot access \"self\" when no class scope is active");
goto failure;
}
ce = scope;
} else if (zend_string_equals_literal_ci(class_name, "parent")) {
if (UNEXPECTED(!scope)) {
zend_throw_error(NULL, "Cannot access \"parent\" when no class scope is active");
goto failure;
} else if (UNEXPECTED(!scope->parent)) {
zend_throw_error(NULL, "Cannot access \"parent\" when current class scope has no parent");
goto failure;
} else {
ce = scope->parent;
}
} else if (zend_string_equals_ci(class_name, ZSTR_KNOWN(ZEND_STR_STATIC))) {
ce = zend_get_called_scope(EG(current_execute_data));
if (UNEXPECTED(!ce)) {
zend_throw_error(NULL, "Cannot access \"static\" when no class scope is active");
goto failure;
}
} else {
ce = zend_fetch_class(class_name, flags);
}
if (ce) {
c = zend_hash_find_ptr(CE_CONSTANTS_TABLE(ce), constant_name);
if (c == NULL) {
if ((flags & ZEND_FETCH_CLASS_SILENT) == 0) {
zend_throw_error(NULL, "Undefined constant %s::%s", ZSTR_VAL(class_name), ZSTR_VAL(constant_name));
goto failure;
}
ret_constant = NULL;
} else {
if (!zend_verify_const_access(c, scope)) {
if ((flags & ZEND_FETCH_CLASS_SILENT) == 0) {
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));
}
goto failure;
}
if (UNEXPECTED(ce->ce_flags & ZEND_ACC_TRAIT)) {
/** Prevent accessing trait constants directly on cases like \defined() or \constant(), etc. */
if ((flags & ZEND_FETCH_CLASS_SILENT) == 0) {
zend_throw_error(NULL, "Cannot access trait constant %s::%s directly", ZSTR_VAL(class_name), ZSTR_VAL(constant_name));
}
goto failure;
}
if (UNEXPECTED(ZEND_CLASS_CONST_FLAGS(c) & ZEND_ACC_DEPRECATED)) {
if ((flags & ZEND_FETCH_CLASS_SILENT) == 0) {
zend_error(E_DEPRECATED, "Constant %s::%s is deprecated", ZSTR_VAL(class_name), ZSTR_VAL(constant_name));
if (EG(exception)) {
goto failure;
}
}
}
ret_constant = &c->value;
}
}
if (ret_constant && Z_TYPE_P(ret_constant) == IS_CONSTANT_AST) {
zend_result ret;
if (IS_CONSTANT_VISITED(ret_constant)) {
zend_throw_error(NULL, "Cannot declare self-referencing constant %s::%s", ZSTR_VAL(class_name), ZSTR_VAL(constant_name));
ret_constant = NULL;
goto failure;
}
MARK_CONSTANT_VISITED(ret_constant);
ret = zend_update_class_constant(c, constant_name, c->ce);
RESET_CONSTANT_VISITED(ret_constant);
if (UNEXPECTED(ret != SUCCESS)) {
ret_constant = NULL;
goto failure;
}
}
failure:
return ret_constant;
}
ZEND_API zval *zend_get_constant_ex(zend_string *cname, zend_class_entry *scope, uint32_t flags)
{
zend_constant *c;
const char *colon;
const char *name = ZSTR_VAL(cname);
size_t name_len = ZSTR_LEN(cname);
/* Skip leading \\ */
if (name[0] == '\\') {
name += 1;
name_len -= 1;
cname = NULL;
}
if ((colon = zend_memrchr(name, ':', name_len)) &&
colon > name && (*(colon - 1) == ':')) {
int class_name_len = colon - name - 1;
size_t const_name_len = name_len - class_name_len - 2;
zend_string *constant_name = zend_string_init(colon + 1, const_name_len, 0);
zend_string *class_name = zend_string_init_interned(name, class_name_len, 0);
zval *ret_constant = zend_get_class_constant_ex(class_name, constant_name, scope, flags);
zend_string_release_ex(class_name, 0);
zend_string_efree(constant_name);
return ret_constant;
/*
zend_class_entry *ce = NULL;
zend_class_constant *c = NULL;
zval *ret_constant = NULL;
if (zend_string_equals_literal_ci(class_name, "self")) {
if (UNEXPECTED(!scope)) {
zend_throw_error(NULL, "Cannot access \"self\" when no class scope is active");
goto failure;
}
ce = scope;
} else if (zend_string_equals_literal_ci(class_name, "parent")) {
if (UNEXPECTED(!scope)) {
zend_throw_error(NULL, "Cannot access \"parent\" when no class scope is active");
goto failure;
} else if (UNEXPECTED(!scope->parent)) {
zend_throw_error(NULL, "Cannot access \"parent\" when current class scope has no parent");
goto failure;
} else {
ce = scope->parent;
}
} else if (zend_string_equals_ci(class_name, ZSTR_KNOWN(ZEND_STR_STATIC))) {
ce = zend_get_called_scope(EG(current_execute_data));
if (UNEXPECTED(!ce)) {
zend_throw_error(NULL, "Cannot access \"static\" when no class scope is active");
goto failure;
}
} else {
ce = zend_fetch_class(class_name, flags);
}
if (ce) {
c = zend_hash_find_ptr(CE_CONSTANTS_TABLE(ce), constant_name);
if (c == NULL) {
if ((flags & ZEND_FETCH_CLASS_SILENT) == 0) {
zend_throw_error(NULL, "Undefined constant %s::%s", ZSTR_VAL(class_name), ZSTR_VAL(constant_name));
goto failure;
}
ret_constant = NULL;
} else {
if (!zend_verify_const_access(c, scope)) {
if ((flags & ZEND_FETCH_CLASS_SILENT) == 0) {
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));
}
goto failure;
}
ret_constant = &c->value;
}
}
if (ret_constant && Z_TYPE_P(ret_constant) == IS_CONSTANT_AST) {
zend_result ret;
if (IS_CONSTANT_VISITED(ret_constant)) {
zend_throw_error(NULL, "Cannot declare self-referencing constant %s::%s", ZSTR_VAL(class_name), ZSTR_VAL(constant_name));
ret_constant = NULL;
goto failure;
}
MARK_CONSTANT_VISITED(ret_constant);
ret = zval_update_constant_ex(ret_constant, c->ce);
RESET_CONSTANT_VISITED(ret_constant);
if (UNEXPECTED(ret != SUCCESS)) {
ret_constant = NULL;
goto failure;
}
}
failure:
zend_string_release_ex(class_name, 0);
zend_string_efree(constant_name);
return ret_constant;
*/
}
/* non-class constant */
if ((colon = zend_memrchr(name, '\\', name_len)) != NULL) {
/* compound constant name */
int prefix_len = colon - name;
size_t const_name_len = name_len - prefix_len - 1;
const char *constant_name = colon + 1;
char *lcname;
size_t lcname_len;
ALLOCA_FLAG(use_heap)
/* Lowercase the namespace portion */
lcname_len = prefix_len + 1 + const_name_len;
lcname = do_alloca(lcname_len + 1, use_heap);
zend_str_tolower_copy(lcname, name, prefix_len);
lcname[prefix_len] = '\\';
memcpy(lcname + prefix_len + 1, constant_name, const_name_len + 1);
c = zend_hash_str_find_ptr(EG(zend_constants), lcname, lcname_len);
free_alloca(lcname, use_heap);
if (!c) {
if (flags & IS_CONSTANT_UNQUALIFIED_IN_NAMESPACE) {
/* name requires runtime resolution, need to check non-namespaced name */
c = zend_get_constant_str_impl(constant_name, const_name_len);
}
}
} else {
if (cname) {
c = zend_get_constant_impl(cname);
} else {
c = zend_get_constant_str_impl(name, name_len);
}
}
if (!c) {
if (!(flags & ZEND_FETCH_CLASS_SILENT)) {
zend_throw_error(NULL, "Undefined constant \"%s\"", name);
}
return NULL;
}
if (!(flags & ZEND_FETCH_CLASS_SILENT) && (ZEND_CONSTANT_FLAGS(c) & CONST_DEPRECATED)) {
zend_error(E_DEPRECATED, "Constant %s is deprecated", name);
}
return &c->value;
}
static void* zend_hash_add_constant(HashTable *ht, zend_string *key, zend_constant *c)
{
void *ret;
zend_constant *copy = pemalloc(sizeof(zend_constant), ZEND_CONSTANT_FLAGS(c) & CONST_PERSISTENT);
memcpy(copy, c, sizeof(zend_constant));
ret = zend_hash_add_ptr(ht, key, copy);
if (!ret) {
pefree(copy, ZEND_CONSTANT_FLAGS(c) & CONST_PERSISTENT);
}
return ret;
}
ZEND_API zend_result zend_register_constant(zend_constant *c)
{
zend_string *lowercase_name = NULL;
zend_string *name;
zend_result ret = SUCCESS;
bool persistent = (ZEND_CONSTANT_FLAGS(c) & CONST_PERSISTENT) != 0;
#if 0
printf("Registering constant for module %d\n", c->module_number);
#endif
const char *slash = strrchr(ZSTR_VAL(c->name), '\\');
if (slash) {
lowercase_name = zend_string_init(ZSTR_VAL(c->name), ZSTR_LEN(c->name), persistent);
zend_str_tolower(ZSTR_VAL(lowercase_name), slash - ZSTR_VAL(c->name));
lowercase_name = zend_new_interned_string(lowercase_name);
name = lowercase_name;
} else {
name = c->name;
}
/* Check if the user is trying to define any special constant */
if (zend_string_equals_literal(name, "__COMPILER_HALT_OFFSET__")
|| (!persistent && zend_get_special_const(ZSTR_VAL(name), ZSTR_LEN(name)))
|| zend_hash_add_constant(EG(zend_constants), name, c) == NULL
) {
zend_error(E_WARNING, "Constant %s already defined", ZSTR_VAL(name));
zend_string_release(c->name);
if (!persistent) {
zval_ptr_dtor_nogc(&c->value);
}
ret = FAILURE;
}
if (lowercase_name) {
zend_string_release(lowercase_name);
}
return ret;
}