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Edit File: zend_string.h
/* +----------------------------------------------------------------------+ | Zend Engine | +----------------------------------------------------------------------+ | Copyright (c) 1998-2018 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: Dmitry Stogov <dmitry@zend.com> | +----------------------------------------------------------------------+ */ /* $Id: $ */ #ifndef ZEND_STRING_H #define ZEND_STRING_H #include "zend.h" BEGIN_EXTERN_C() ZEND_API extern zend_string *(*zend_new_interned_string)(zend_string *str); ZEND_API extern void (*zend_interned_strings_snapshot)(void); ZEND_API extern void (*zend_interned_strings_restore)(void); ZEND_API zend_ulong zend_hash_func(const char *str, size_t len); void zend_interned_strings_init(void); void zend_interned_strings_dtor(void); void zend_known_interned_strings_init(zend_string ***, uint32_t *); ZEND_API zend_string *zend_string_concat3( const char *str1, size_t str1_len, const char *str2, size_t str2_len, const char *str3, size_t str3_len); END_EXTERN_C() /* Shortcuts */ #define ZSTR_VAL(zstr) (zstr)->val #define ZSTR_LEN(zstr) (zstr)->len #define ZSTR_MAX_OVERHEAD (ZEND_MM_ALIGNED_SIZE(_ZSTR_HEADER_SIZE + 1)) #define ZSTR_MAX_LEN (SIZE_MAX - ZSTR_MAX_OVERHEAD) #define ZSTR_H(zstr) (zstr)->h #define ZSTR_HASH(zstr) zend_string_hash_val(zstr) /* Compatibility macros */ #define IS_INTERNED(s) ZSTR_IS_INTERNED(s) #define STR_EMPTY_ALLOC() ZSTR_EMPTY_ALLOC() #define _STR_HEADER_SIZE _ZSTR_HEADER_SIZE #define STR_ALLOCA_ALLOC(str, _len, use_heap) ZSTR_ALLOCA_ALLOC(str, _len, use_heap) #define STR_ALLOCA_INIT(str, s, len, use_heap) ZSTR_ALLOCA_INIT(str, s, len, use_heap) #define STR_ALLOCA_FREE(str, use_heap) ZSTR_ALLOCA_FREE(str, use_heap) /*---*/ #define ZSTR_IS_INTERNED(s) (GC_FLAGS(s) & IS_STR_INTERNED) #define ZSTR_EMPTY_ALLOC() CG(empty_string) #define _ZSTR_HEADER_SIZE XtOffsetOf(zend_string, val) #define _ZSTR_STRUCT_SIZE(len) (_ZSTR_HEADER_SIZE + len + 1) #define ZSTR_ALLOCA_ALLOC(str, _len, use_heap) do { \ (str) = (zend_string *)do_alloca(ZEND_MM_ALIGNED_SIZE_EX(_ZSTR_STRUCT_SIZE(_len), 8), (use_heap)); \ GC_REFCOUNT(str) = 1; \ GC_TYPE_INFO(str) = IS_STRING; \ zend_string_forget_hash_val(str); \ ZSTR_LEN(str) = _len; \ } while (0) #define ZSTR_ALLOCA_INIT(str, s, len, use_heap) do { \ ZSTR_ALLOCA_ALLOC(str, len, use_heap); \ memcpy(ZSTR_VAL(str), (s), (len)); \ ZSTR_VAL(str)[(len)] = '\0'; \ } while (0) #define ZSTR_ALLOCA_FREE(str, use_heap) free_alloca(str, use_heap) #define ZSTR_INIT_LITERAL(s, persistent) (zend_string_init((s), strlen(s), (persistent))) /*---*/ static zend_always_inline zend_ulong zend_string_hash_val(zend_string *s) { if (!ZSTR_H(s)) { ZSTR_H(s) = zend_hash_func(ZSTR_VAL(s), ZSTR_LEN(s)); } return ZSTR_H(s); } static zend_always_inline void zend_string_forget_hash_val(zend_string *s) { ZSTR_H(s) = 0; } static zend_always_inline uint32_t zend_string_refcount(const zend_string *s) { if (!ZSTR_IS_INTERNED(s)) { return GC_REFCOUNT(s); } return 1; } static zend_always_inline uint32_t zend_string_addref(zend_string *s) { if (!ZSTR_IS_INTERNED(s)) { return ++GC_REFCOUNT(s); } return 1; } static zend_always_inline uint32_t zend_string_delref(zend_string *s) { if (!ZSTR_IS_INTERNED(s)) { return --GC_REFCOUNT(s); } return 1; } static zend_always_inline zend_string *zend_string_alloc(size_t len, int persistent) { zend_string *ret = (zend_string *)pemalloc(ZEND_MM_ALIGNED_SIZE(_ZSTR_STRUCT_SIZE(len)), persistent); GC_REFCOUNT(ret) = 1; #if 1 /* optimized single assignment */ GC_TYPE_INFO(ret) = IS_STRING | ((persistent ? IS_STR_PERSISTENT : 0) << 8); #else GC_TYPE(ret) = IS_STRING; GC_FLAGS(ret) = (persistent ? IS_STR_PERSISTENT : 0); GC_INFO(ret) = 0; #endif zend_string_forget_hash_val(ret); ZSTR_LEN(ret) = len; return ret; } static zend_always_inline zend_string *zend_string_safe_alloc(size_t n, size_t m, size_t l, int persistent) { zend_string *ret = (zend_string *)safe_pemalloc(n, m, ZEND_MM_ALIGNED_SIZE(_ZSTR_STRUCT_SIZE(l)), persistent); GC_REFCOUNT(ret) = 1; #if 1 /* optimized single assignment */ GC_TYPE_INFO(ret) = IS_STRING | ((persistent ? IS_STR_PERSISTENT : 0) << 8); #else GC_TYPE(ret) = IS_STRING; GC_FLAGS(ret) = (persistent ? IS_STR_PERSISTENT : 0); GC_INFO(ret) = 0; #endif zend_string_forget_hash_val(ret); ZSTR_LEN(ret) = (n * m) + l; return ret; } static zend_always_inline zend_string *zend_string_init(const char *str, size_t len, int persistent) { zend_string *ret = zend_string_alloc(len, persistent); memcpy(ZSTR_VAL(ret), str, len); ZSTR_VAL(ret)[len] = '\0'; return ret; } static zend_always_inline zend_string *zend_string_copy(zend_string *s) { if (!ZSTR_IS_INTERNED(s)) { GC_REFCOUNT(s)++; } return s; } static zend_always_inline zend_string *zend_string_dup(zend_string *s, int persistent) { if (ZSTR_IS_INTERNED(s)) { return s; } else { return zend_string_init(ZSTR_VAL(s), ZSTR_LEN(s), persistent); } } static zend_always_inline zend_string *zend_string_realloc(zend_string *s, size_t len, int persistent) { zend_string *ret; if (!ZSTR_IS_INTERNED(s)) { if (EXPECTED(GC_REFCOUNT(s) == 1)) { ret = (zend_string *)perealloc(s, ZEND_MM_ALIGNED_SIZE(_ZSTR_STRUCT_SIZE(len)), persistent); ZSTR_LEN(ret) = len; zend_string_forget_hash_val(ret); return ret; } } ret = zend_string_alloc(len, persistent); memcpy(ZSTR_VAL(ret), ZSTR_VAL(s), MIN(len, ZSTR_LEN(s)) + 1); if (!ZSTR_IS_INTERNED(s)) { GC_REFCOUNT(s)--; } return ret; } static zend_always_inline zend_string *zend_string_extend(zend_string *s, size_t len, int persistent) { zend_string *ret; ZEND_ASSERT(len >= ZSTR_LEN(s)); if (!ZSTR_IS_INTERNED(s)) { if (EXPECTED(GC_REFCOUNT(s) == 1)) { ret = (zend_string *)perealloc(s, ZEND_MM_ALIGNED_SIZE(_ZSTR_STRUCT_SIZE(len)), persistent); ZSTR_LEN(ret) = len; zend_string_forget_hash_val(ret); return ret; } } ret = zend_string_alloc(len, persistent); memcpy(ZSTR_VAL(ret), ZSTR_VAL(s), ZSTR_LEN(s) + 1); if (!ZSTR_IS_INTERNED(s)) { GC_REFCOUNT(s)--; } return ret; } static zend_always_inline zend_string *zend_string_truncate(zend_string *s, size_t len, int persistent) { zend_string *ret; ZEND_ASSERT(len <= ZSTR_LEN(s)); if (!ZSTR_IS_INTERNED(s)) { if (EXPECTED(GC_REFCOUNT(s) == 1)) { ret = (zend_string *)perealloc(s, ZEND_MM_ALIGNED_SIZE(_ZSTR_STRUCT_SIZE(len)), persistent); ZSTR_LEN(ret) = len; zend_string_forget_hash_val(ret); return ret; } } ret = zend_string_alloc(len, persistent); memcpy(ZSTR_VAL(ret), ZSTR_VAL(s), len + 1); if (!ZSTR_IS_INTERNED(s)) { GC_REFCOUNT(s)--; } return ret; } static zend_always_inline zend_string *zend_string_safe_realloc(zend_string *s, size_t n, size_t m, size_t l, int persistent) { zend_string *ret; if (!ZSTR_IS_INTERNED(s)) { if (GC_REFCOUNT(s) == 1) { ret = (zend_string *)safe_perealloc(s, n, m, ZEND_MM_ALIGNED_SIZE(_ZSTR_STRUCT_SIZE(l)), persistent); ZSTR_LEN(ret) = (n * m) + l; zend_string_forget_hash_val(ret); return ret; } } ret = zend_string_safe_alloc(n, m, l, persistent); memcpy(ZSTR_VAL(ret), ZSTR_VAL(s), MIN((n * m) + l, ZSTR_LEN(s)) + 1); if (!ZSTR_IS_INTERNED(s)) { GC_REFCOUNT(s)--; } return ret; } static zend_always_inline void zend_string_free(zend_string *s) { if (!ZSTR_IS_INTERNED(s)) { ZEND_ASSERT(GC_REFCOUNT(s) <= 1); pefree(s, GC_FLAGS(s) & IS_STR_PERSISTENT); } } static zend_always_inline void zend_string_release(zend_string *s) { if (!ZSTR_IS_INTERNED(s)) { if (--GC_REFCOUNT(s) == 0) { pefree(s, GC_FLAGS(s) & IS_STR_PERSISTENT); } } } static zend_always_inline zend_bool zend_string_equals(zend_string *s1, zend_string *s2) { return s1 == s2 || (ZSTR_LEN(s1) == ZSTR_LEN(s2) && !memcmp(ZSTR_VAL(s1), ZSTR_VAL(s2), ZSTR_LEN(s1))); } #define zend_string_equals_ci(s1, s2) \ (ZSTR_LEN(s1) == ZSTR_LEN(s2) && !zend_binary_strcasecmp(ZSTR_VAL(s1), ZSTR_LEN(s1), ZSTR_VAL(s2), ZSTR_LEN(s2))) #define zend_string_equals_literal_ci(str, c) \ (ZSTR_LEN(str) == sizeof(c) - 1 && !zend_binary_strcasecmp(ZSTR_VAL(str), ZSTR_LEN(str), (c), sizeof(c) - 1)) #define zend_string_equals_literal(str, literal) \ (ZSTR_LEN(str) == sizeof(literal)-1 && !memcmp(ZSTR_VAL(str), literal, sizeof(literal) - 1)) /* * DJBX33A (Daniel J. Bernstein, Times 33 with Addition) * * This is Daniel J. Bernstein's popular `times 33' hash function as * posted by him years ago on comp.lang.c. It basically uses a function * like ``hash(i) = hash(i-1) * 33 + str[i]''. This is one of the best * known hash functions for strings. Because it is both computed very * fast and distributes very well. * * The magic of number 33, i.e. why it works better than many other * constants, prime or not, has never been adequately explained by * anyone. So I try an explanation: if one experimentally tests all * multipliers between 1 and 256 (as RSE did now) one detects that even * numbers are not useable at all. The remaining 128 odd numbers * (except for the number 1) work more or less all equally well. They * all distribute in an acceptable way and this way fill a hash table * with an average percent of approx. 86%. * * If one compares the Chi^2 values of the variants, the number 33 not * even has the best value. But the number 33 and a few other equally * good numbers like 17, 31, 63, 127 and 129 have nevertheless a great * advantage to the remaining numbers in the large set of possible * multipliers: their multiply operation can be replaced by a faster * operation based on just one shift plus either a single addition * or subtraction operation. And because a hash function has to both * distribute good _and_ has to be very fast to compute, those few * numbers should be preferred and seems to be the reason why Daniel J. * Bernstein also preferred it. * * * -- Ralf S. Engelschall <rse@engelschall.com> */ static zend_always_inline zend_ulong zend_inline_hash_func(const char *str, size_t len) { zend_ulong hash = Z_UL(5381); /* variant with the hash unrolled eight times */ for (; len >= 8; len -= 8) { hash = ((hash << 5) + hash) + *str++; hash = ((hash << 5) + hash) + *str++; hash = ((hash << 5) + hash) + *str++; hash = ((hash << 5) + hash) + *str++; hash = ((hash << 5) + hash) + *str++; hash = ((hash << 5) + hash) + *str++; hash = ((hash << 5) + hash) + *str++; hash = ((hash << 5) + hash) + *str++; } switch (len) { case 7: hash = ((hash << 5) + hash) + *str++; /* fallthrough... */ case 6: hash = ((hash << 5) + hash) + *str++; /* fallthrough... */ case 5: hash = ((hash << 5) + hash) + *str++; /* fallthrough... */ case 4: hash = ((hash << 5) + hash) + *str++; /* fallthrough... */ case 3: hash = ((hash << 5) + hash) + *str++; /* fallthrough... */ case 2: hash = ((hash << 5) + hash) + *str++; /* fallthrough... */ case 1: hash = ((hash << 5) + hash) + *str++; break; case 0: break; EMPTY_SWITCH_DEFAULT_CASE() } /* Hash value can't be zero, so we always set the high bit */ #if SIZEOF_ZEND_LONG == 8 return hash | Z_UL(0x8000000000000000); #elif SIZEOF_ZEND_LONG == 4 return hash | Z_UL(0x80000000); #else # error "Unknown SIZEOF_ZEND_LONG" #endif } #ifdef ZTS static zend_always_inline zend_string* zend_zts_interned_string_init(const char *val, size_t len) { zend_string *str; str = zend_string_init(val, len, 1); zend_string_hash_val(str); GC_FLAGS(str) |= IS_STR_INTERNED; return str; } static zend_always_inline void zend_zts_interned_string_free(zend_string **s) { if (NULL != *s) { free(*s); *s = NULL; } } #endif #define ZEND_KNOWN_STRINGS(_) \ _(ZEND_STR_FILE, "file") \ _(ZEND_STR_LINE, "line") \ _(ZEND_STR_FUNCTION, "function") \ _(ZEND_STR_CLASS, "class") \ _(ZEND_STR_OBJECT, "object") \ _(ZEND_STR_TYPE, "type") \ _(ZEND_STR_OBJECT_OPERATOR, "->") \ _(ZEND_STR_PAAMAYIM_NEKUDOTAYIM, "::") \ _(ZEND_STR_ARGS, "args") \ _(ZEND_STR_UNKNOWN, "unknown") \ _(ZEND_STR_EVAL, "eval") \ _(ZEND_STR_INCLUDE, "include") \ _(ZEND_STR_REQUIRE, "require") \ _(ZEND_STR_INCLUDE_ONCE, "include_once") \ _(ZEND_STR_REQUIRE_ONCE, "require_once") \ _(ZEND_STR_SCALAR, "scalar") \ _(ZEND_STR_ERROR_REPORTING, "error_reporting") \ _(ZEND_STR_STATIC, "static") \ _(ZEND_STR_THIS, "this") \ _(ZEND_STR_VALUE, "value") \ _(ZEND_STR_KEY, "key") \ _(ZEND_STR_MAGIC_AUTOLOAD, "__autoload") \ _(ZEND_STR_MAGIC_INVOKE, "__invoke") \ _(ZEND_STR_PREVIOUS, "previous") \ _(ZEND_STR_CODE, "code") \ _(ZEND_STR_MESSAGE, "message") \ _(ZEND_STR_SEVERITY, "severity") \ _(ZEND_STR_STRING, "string") \ _(ZEND_STR_TRACE, "trace") \ typedef enum _zend_known_string_id { #define _ZEND_STR_ID(id, str) id, ZEND_KNOWN_STRINGS(_ZEND_STR_ID) #undef _ZEND_STR_ID ZEND_STR_LAST_KNOWN } zend_known_string_id; ZEND_API uint32_t zend_intern_known_strings(const char **strings, uint32_t count); #endif /* ZEND_STRING_H */ /* * Local variables: * tab-width: 4 * c-basic-offset: 4 * indent-tabs-mode: t * End: */