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in_array() php内置函数的源码解读

/* {{{ proto mixed array_search(mixed needle, array haystack [, bool strict])
   Searches the array for a given value and returns the corresponding key if successful */
PHP_FUNCTION(array_search)
{
	php_search_array(INTERNAL_FUNCTION_PARAM_PASSTHRU, 1);
}

PHP_FUNCTION(in_array)
{
	php_search_array(INTERNAL_FUNCTION_PARAM_PASSTHRU, 0);
}

/* void php_search_array(INTERNAL_FUNCTION_PARAMETERS, int behavior)
 * 0 = return boolean
 * 1 = return key
 */
 static inline void php_search_array(INTERNAL_FUNCTION_PARAMETERS, int behavior) /* {{{ */
{
	zval *value,				/* value to check for */
		 *array,				/* array to check in */
		 *entry;				/* pointer to array entry */
	zend_ulong num_idx;
	zend_string *str_idx;
	zend_bool strict = 0;		/* strict comparison or not */

	ZEND_PARSE_PARAMETERS_START(2, 3) /* 开始接收参数 */
	/*第一个参数表示必传的参数个数，第二个参数表示最多传入的参数个数。*/
		Z_PARAM_ZVAL(value)			  /* 接收必填参数(这个参数可能是int也可能是str) 所以没有指定类型*/
		Z_PARAM_ARRAY(array)		  /* 接收必填参数数组类型 */
		Z_PARAM_OPTIONAL
		Z_PARAM_BOOL(strict)		  /* 接收选填参数bool类型 */
	ZEND_PARSE_PARAMETERS_END();	  /* 结束 */

	if (strict) {
		ZEND_HASH_FOREACH_KEY_VAL_IND(Z_ARRVAL_P(array), num_idx, str_idx, entry) {
			ZVAL_DEREF(entry);
			if (fast_is_identical_function(value, entry)) {
				if (behavior == 0) {
					RETURN_TRUE;
				} else {
					if (str_idx) {
						RETVAL_STR_COPY(str_idx);
					} else {
						RETVAL_LONG(num_idx);
					}
					return;
				}
			}
		} ZEND_HASH_FOREACH_END();
	} else { /* 理解下下边这块 _p 是指针，_pp 是指针的指针*/ /*  */
		if (Z_TYPE_P(value) == IS_LONG) { /* 按照value的值的类型来处理 IS_LONG 是长整型 */
			ZEND_HASH_FOREACH_KEY_VAL_IND(Z_ARRVAL_P(array), num_idx, str_idx, entry) {/* ZEND_HASH_FOREACH_KEY_VAL_IND 函数意思是zend遍历 间接zval 类型数据 */

				if (fast_equal_check_long(value, entry)) {
					if (behavior == 0) { /* 这里是 in_array() */
						RETURN_TRUE;
					} else { 			 /* 这里是 array_search() */
						if (str_idx) {
							RETVAL_STR_COPY(str_idx); /* 字符串类型的返回值 */
						} else {
							RETVAL_LONG(num_idx);	/* 整型返回值 */
						}
						return;/* 为了提前结束函数 */
					}
				}
			} ZEND_HASH_FOREACH_END();/* 遍历结束 */
		} else if (Z_TYPE_P(value) == IS_STRING) {
			ZEND_HASH_FOREACH_KEY_VAL_IND(Z_ARRVAL_P(array), num_idx, str_idx, entry) {
				if (fast_equal_check_string(value, entry)) {
					if (behavior == 0) {
						RETURN_TRUE;
					} else {
						if (str_idx) {
							RETVAL_STR_COPY(str_idx);
						} else {
							RETVAL_LONG(num_idx);
						}
						return;
					}
				}
			} ZEND_HASH_FOREACH_END();
		} else {
			ZEND_HASH_FOREACH_KEY_VAL_IND(Z_ARRVAL_P(array), num_idx, str_idx, entry) {
				if (fast_equal_check_function(value, entry)) {
					if (behavior == 0) {
						RETURN_TRUE;
					} else {
						if (str_idx) {
							RETVAL_STR_COPY(str_idx);
						} else {
							RETVAL_LONG(num_idx);
						}
						return;
					}
				}
			} ZEND_HASH_FOREACH_END();
 		}
	}

	RETURN_FALSE;
}
 
static zend_always_inline int fast_equal_check_long(zval *op1, zval *op2)
/* zend_always_inline 含义函数开始执行时，需要为函数分配相应的函数栈帧并入栈 */
{
	zval result;
	if (EXPECTED(Z_TYPE_P(op2) == IS_LONG)) { /* 都为整型的时候 */
		return Z_LVAL_P(op1) == Z_LVAL_P(op2); /* 直接比较 相同true 不相同 false*/
	}
	compare_function(&result, op1, op2); /* 类型不一样的时候用这个函数 */
	return Z_LVAL(result) == 0; /* 把result值读出来比较返回值 */
}

ZEND_API int ZEND_FASTCALL compare_function(zval *result, zval *op1, zval *op2) 
{
	int ret;
	int converted = 0;
	zval op1_copy, op2_copy;
	zval *op_free, tmp_free;

	while (1) {
		switch (TYPE_PAIR(Z_TYPE_P(op1), Z_TYPE_P(op2))) {
			case TYPE_PAIR(IS_LONG, IS_LONG):
				ZVAL_LONG(result, Z_LVAL_P(op1)>Z_LVAL_P(op2)?1:(Z_LVAL_P(op1)<Z_LVAL_P(op2)?-1:0));
				return SUCCESS;

			case TYPE_PAIR(IS_DOUBLE, IS_LONG):
				Z_DVAL_P(result) = Z_DVAL_P(op1) - (double)Z_LVAL_P(op2);
				ZVAL_LONG(result, ZEND_NORMALIZE_BOOL(Z_DVAL_P(result)));
				return SUCCESS;

			case TYPE_PAIR(IS_LONG, IS_DOUBLE):
				Z_DVAL_P(result) = (double)Z_LVAL_P(op1) - Z_DVAL_P(op2);
				ZVAL_LONG(result, ZEND_NORMALIZE_BOOL(Z_DVAL_P(result)));
				return SUCCESS;

			case TYPE_PAIR(IS_DOUBLE, IS_DOUBLE):
				if (Z_DVAL_P(op1) == Z_DVAL_P(op2)) {
					ZVAL_LONG(result, 0);
				} else {
					Z_DVAL_P(result) = Z_DVAL_P(op1) - Z_DVAL_P(op2);
					ZVAL_LONG(result, ZEND_NORMALIZE_BOOL(Z_DVAL_P(result)));
				}
				return SUCCESS;

			case TYPE_PAIR(IS_ARRAY, IS_ARRAY):
				ZVAL_LONG(result, zend_compare_arrays(op1, op2));
				return SUCCESS;

			case TYPE_PAIR(IS_NULL, IS_NULL):
			case TYPE_PAIR(IS_NULL, IS_FALSE):
			case TYPE_PAIR(IS_FALSE, IS_NULL):
			case TYPE_PAIR(IS_FALSE, IS_FALSE):
			case TYPE_PAIR(IS_TRUE, IS_TRUE):
				ZVAL_LONG(result, 0);
				return SUCCESS;

			case TYPE_PAIR(IS_NULL, IS_TRUE):
				ZVAL_LONG(result, -1);
				return SUCCESS;

			case TYPE_PAIR(IS_TRUE, IS_NULL):
				ZVAL_LONG(result, 1);
				return SUCCESS;

			case TYPE_PAIR(IS_STRING, IS_STRING):
				if (Z_STR_P(op1) == Z_STR_P(op2)) {
					ZVAL_LONG(result, 0);
					return SUCCESS;
				}
				ZVAL_LONG(result, zendi_smart_strcmp(Z_STR_P(op1), Z_STR_P(op2)));
				return SUCCESS;

			case TYPE_PAIR(IS_NULL, IS_STRING):
				ZVAL_LONG(result, Z_STRLEN_P(op2) == 0 ? 0 : -1);
				return SUCCESS;

			case TYPE_PAIR(IS_STRING, IS_NULL):
				ZVAL_LONG(result, Z_STRLEN_P(op1) == 0 ? 0 : 1);
				return SUCCESS;

			case TYPE_PAIR(IS_OBJECT, IS_NULL):
				ZVAL_LONG(result, 1);
				return SUCCESS;

			case TYPE_PAIR(IS_NULL, IS_OBJECT):
				ZVAL_LONG(result, -1);
				return SUCCESS;

			default:
				if (Z_ISREF_P(op1)) {
					op1 = Z_REFVAL_P(op1);
					continue;
				} else if (Z_ISREF_P(op2)) {
					op2 = Z_REFVAL_P(op2);
					continue;
				}

				if (Z_TYPE_P(op1) == IS_OBJECT && Z_OBJ_HANDLER_P(op1, compare)) {
					ret = Z_OBJ_HANDLER_P(op1, compare)(result, op1, op2);
					if (UNEXPECTED(Z_TYPE_P(result) != IS_LONG)) {
						convert_compare_result_to_long(result);
					}
					return ret;
				} else if (Z_TYPE_P(op2) == IS_OBJECT && Z_OBJ_HANDLER_P(op2, compare)) {
					ret = Z_OBJ_HANDLER_P(op2, compare)(result, op1, op2);
					if (UNEXPECTED(Z_TYPE_P(result) != IS_LONG)) {
						convert_compare_result_to_long(result);
					}
					return ret;
				}

				if (Z_TYPE_P(op1) == IS_OBJECT && Z_TYPE_P(op2) == IS_OBJECT) {
					if (Z_OBJ_P(op1) == Z_OBJ_P(op2)) {
						/* object handles are identical, apparently this is the same object */
						ZVAL_LONG(result, 0);
						return SUCCESS;
					}
					if (Z_OBJ_HANDLER_P(op1, compare_objects) == Z_OBJ_HANDLER_P(op2, compare_objects)) {
						ZVAL_LONG(result, Z_OBJ_HANDLER_P(op1, compare_objects)(op1, op2));
						return SUCCESS;
					}
				}
				if (Z_TYPE_P(op1) == IS_OBJECT) {
					if (Z_OBJ_HT_P(op1)->get) {
						zval rv;
						op_free = Z_OBJ_HT_P(op1)->get(op1, &rv);
						ret = compare_function(result, op_free, op2);
						zend_free_obj_get_result(op_free);
						return ret;
					} else if (Z_TYPE_P(op2) != IS_OBJECT && Z_OBJ_HT_P(op1)->cast_object) {
						ZVAL_UNDEF(&tmp_free);
						if (Z_OBJ_HT_P(op1)->cast_object(op1, &tmp_free, ((Z_TYPE_P(op2) == IS_FALSE || Z_TYPE_P(op2) == IS_TRUE) ? _IS_BOOL : Z_TYPE_P(op2))) == FAILURE) {
							ZVAL_LONG(result, 1);
							zend_free_obj_get_result(&tmp_free);
							return SUCCESS;
						}
						ret = compare_function(result, &tmp_free, op2);
						zend_free_obj_get_result(&tmp_free);
						return ret;
					}
				}
				if (Z_TYPE_P(op2) == IS_OBJECT) {
					if (Z_OBJ_HT_P(op2)->get) {
						zval rv;
						op_free = Z_OBJ_HT_P(op2)->get(op2, &rv);
						ret = compare_function(result, op1, op_free);
						zend_free_obj_get_result(op_free);
						return ret;
					} else if (Z_TYPE_P(op1) != IS_OBJECT && Z_OBJ_HT_P(op2)->cast_object) {
						ZVAL_UNDEF(&tmp_free);
						if (Z_OBJ_HT_P(op2)->cast_object(op2, &tmp_free, ((Z_TYPE_P(op1) == IS_FALSE || Z_TYPE_P(op1) == IS_TRUE) ? _IS_BOOL : Z_TYPE_P(op1))) == FAILURE) {
							ZVAL_LONG(result, -1);
							zend_free_obj_get_result(&tmp_free);
							return SUCCESS;
						}
						ret = compare_function(result, op1, &tmp_free);
						zend_free_obj_get_result(&tmp_free);
						return ret;
					} else if (Z_TYPE_P(op1) == IS_OBJECT) {
						ZVAL_LONG(result, 1);
						return SUCCESS;
					}
				}
				if (!converted) {
					if (Z_TYPE_P(op1) == IS_NULL || Z_TYPE_P(op1) == IS_FALSE) {
						ZVAL_LONG(result, zval_is_true(op2) ? -1 : 0);
						return SUCCESS;
					} else if (Z_TYPE_P(op2) == IS_NULL || Z_TYPE_P(op2) == IS_FALSE) {
						ZVAL_LONG(result, zval_is_true(op1) ? 1 : 0);
						return SUCCESS;
					} else if (Z_TYPE_P(op1) == IS_TRUE) {
						ZVAL_LONG(result, zval_is_true(op2) ? 0 : 1);
						return SUCCESS;
					} else if (Z_TYPE_P(op2) == IS_TRUE) {
						ZVAL_LONG(result, zval_is_true(op1) ? 0 : -1);
						return SUCCESS;
					} else {
						op1 = zendi_convert_scalar_to_number(op1, &op1_copy, result, 1);
						op2 = zendi_convert_scalar_to_number(op2, &op2_copy, result, 1);
						if (EG(exception)) {
							if (result != op1) {
								ZVAL_UNDEF(result);
							}
							return FAILURE;
						}
						converted = 1;
					}
				} else if (Z_TYPE_P(op1)==IS_ARRAY) {
					ZVAL_LONG(result, 1);
					return SUCCESS;
				} else if (Z_TYPE_P(op2)==IS_ARRAY) {
					ZVAL_LONG(result, -1);
					return SUCCESS;
				} else if (Z_TYPE_P(op1)==IS_OBJECT) {
					ZVAL_LONG(result, 1);
					return SUCCESS;
				} else if (Z_TYPE_P(op2)==IS_OBJECT) {
					ZVAL_LONG(result, -1);
					return SUCCESS;
				} else {
					ZVAL_LONG(result, 0);
					return FAILURE;
				}
		}
	}
}

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