include/android_stub/cutils/properties.h

   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