1 /* 2 * Copyright (C) 2006 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #pragma once 18 19 #include <sys/cdefs.h> 20 #include <stddef.h> 21 #include <stdint.h> 22 23 #if __has_include(<sys/system_properties.h>) 24 #include <sys/system_properties.h> 25 #else 26 #define PROP_VALUE_MAX 92 27 #endif 28 29 #ifdef __cplusplus 30 extern "C" { 31 #endif 32 33 // 34 // Deprecated. 35 // 36 // See <android-base/properties.h> for better API. 37 // 38 39 #define PROPERTY_KEY_MAX PROP_NAME_MAX 40 #define PROPERTY_VALUE_MAX PROP_VALUE_MAX 41 42 /* property_get: returns the length of the value which will never be 43 ** greater than PROPERTY_VALUE_MAX - 1 and will always be zero terminated. 44 ** (the length does not include the terminating zero). 45 ** 46 ** If the property read fails or returns an empty value, the default 47 ** value is used (if nonnull). 48 */ 49 int property_get(const char* key, char* value, const char* default_value); 50 51 /* property_get_bool: returns the value of key coerced into a 52 ** boolean. If the property is not set, then the default value is returned. 53 ** 54 * The following is considered to be true (1): 55 ** "1", "true", "y", "yes", "on" 56 ** 57 ** The following is considered to be false (0): 58 ** "0", "false", "n", "no", "off" 59 ** 60 ** The conversion is whitespace-sensitive (e.g. " off" will not be false). 61 ** 62 ** If no property with this key is set (or the key is NULL) or the boolean 63 ** conversion fails, the default value is returned. 64 **/ 65 int8_t property_get_bool(const char *key, int8_t default_value); 66 67 /* property_get_int64: returns the value of key truncated and coerced into a 68 ** int64_t. If the property is not set, then the default value is used. 69 ** 70 ** The numeric conversion is identical to strtoimax with the base inferred: 71 ** - All digits up to the first non-digit characters are read 72 ** - The longest consecutive prefix of digits is converted to a long 73 ** 74 ** Valid strings of digits are: 75 ** - An optional sign character + or - 76 ** - An optional prefix indicating the base (otherwise base 10 is assumed) 77 ** -- 0 prefix is octal 78 ** -- 0x / 0X prefix is hex 79 ** 80 ** Leading/trailing whitespace is ignored. Overflow/underflow will cause 81 ** numeric conversion to fail. 82 ** 83 ** If no property with this key is set (or the key is NULL) or the numeric 84 ** conversion fails, the default value is returned. 85 **/ 86 int64_t property_get_int64(const char *key, int64_t default_value); 87 88 /* property_get_int32: returns the value of key truncated and coerced into an 89 ** int32_t. If the property is not set, then the default value is used. 90 ** 91 ** The numeric conversion is identical to strtoimax with the base inferred: 92 ** - All digits up to the first non-digit characters are read 93 ** - The longest consecutive prefix of digits is converted to a long 94 ** 95 ** Valid strings of digits are: 96 ** - An optional sign character + or - 97 ** - An optional prefix indicating the base (otherwise base 10 is assumed) 98 ** -- 0 prefix is octal 99 ** -- 0x / 0X prefix is hex 100 ** 101 ** Leading/trailing whitespace is ignored. Overflow/underflow will cause 102 ** numeric conversion to fail. 103 ** 104 ** If no property with this key is set (or the key is NULL) or the numeric 105 ** conversion fails, the default value is returned. 106 **/ 107 int32_t property_get_int32(const char *key, int32_t default_value); 108 109 /* property_set: returns 0 on success, < 0 on failure 110 */ 111 int property_set(const char *key, const char *value); 112 113 int property_list(void (*propfn)(const char *key, const char *value, void *cookie), void *cookie); 114 115 #if defined(__BIONIC_FORTIFY) 116 #define __property_get_err_str "property_get() called with too small of a buffer" 117 118 #if defined(__clang__) 119 120 /* Some projects use -Weverything; diagnose_if is clang-specific. */ 121 #pragma clang diagnostic push 122 #pragma clang diagnostic ignored "-Wgcc-compat" 123 int property_get(const char* key, char* value, const char* default_value) 124 __clang_error_if(__bos(value) != __BIONIC_FORTIFY_UNKNOWN_SIZE && 125 __bos(value) < PROPERTY_VALUE_MAX, 126 __property_get_err_str); 127 #pragma clang diagnostic pop 128 129 #else /* defined(__clang__) */ 130 131 extern int __property_get_real(const char *, char *, const char *) 132 __asm__(__USER_LABEL_PREFIX__ "property_get"); 133 __errordecl(__property_get_too_small_error, __property_get_err_str); 134 135 __BIONIC_FORTIFY_INLINE 136 int property_get(const char *key, char *value, const char *default_value) { 137 size_t bos = __bos(value); 138 if (bos < PROPERTY_VALUE_MAX) { 139 __property_get_too_small_error(); 140 } 141 return __property_get_real(key, value, default_value); 142 } 143 144 #endif /* defined(__clang__) */ 145 146 #undef __property_get_err_str 147 #endif /* defined(__BIONIC_FORTIFY) */ 148 149 #ifdef __cplusplus 150 } 151 #endif 152