1 /* 2 * Copyright (C) 2008 The Android Open Source Project 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * * Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * * Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in 12 * the documentation and/or other materials provided with the 13 * distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 16 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 17 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 18 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 19 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 22 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 25 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 #ifndef _INCLUDE_SYS_SYSTEM_PROPERTIES_H 30 #define _INCLUDE_SYS_SYSTEM_PROPERTIES_H 31 32 #include <sys/cdefs.h> 33 #include <stdbool.h> 34 #include <stddef.h> 35 #include <stdint.h> 36 37 __BEGIN_DECLS 38 39 typedef struct prop_info prop_info; 40 41 #define PROP_VALUE_MAX 92 42 43 /* 44 * Sets system property `name` to `value`, creating the system property if it doesn't already exist. 45 */ 46 int __system_property_set(const char* __name, const char* __value) __INTRODUCED_IN(12); 47 48 /* 49 * Returns a `prop_info` corresponding system property `name`, or nullptr if it doesn't exist. 50 * Use __system_property_read_callback to query the current value. 51 * 52 * Property lookup is expensive, so it can be useful to cache the result of this function. 53 */ 54 const prop_info* __system_property_find(const char* __name); 55 56 /* 57 * Calls `callback` with a consistent trio of name, value, and serial number for property `pi`. 58 */ 59 void __system_property_read_callback(const prop_info* __pi, 60 void (*__callback)(void* __cookie, const char* __name, const char* __value, uint32_t __serial), 61 void* __cookie) __INTRODUCED_IN(26); 62 63 /* 64 * Passes a `prop_info` for each system property to the provided 65 * callback. Use __system_property_read_callback() to read the value. 66 * 67 * This method is for inspecting and debugging the property system, and not generally useful. 68 */ 69 int __system_property_foreach(void (*__callback)(const prop_info* __pi, void* __cookie), void* __cookie) 70 __INTRODUCED_IN(19); 71 72 /* 73 * Waits for the specific system property identified by `pi` to be updated 74 * past `old_serial`. Waits no longer than `relative_timeout`, or forever 75 * if `relaive_timeout` is null. 76 * 77 * If `pi` is null, waits for the global serial number instead. 78 * 79 * If you don't know the current serial, use 0. 80 * 81 * Returns true and updates `*new_serial_ptr` on success, or false if the call 82 * timed out. 83 */ 84 struct timespec; 85 bool __system_property_wait(const prop_info* __pi, uint32_t __old_serial, uint32_t* __new_serial_ptr, const struct timespec* __relative_timeout) 86 __INTRODUCED_IN(26); 87 88 /* Deprecated. In Android O and above, there's no limit on property name length. */ 89 #define PROP_NAME_MAX 32 90 /* Deprecated. Use __system_property_read_callback instead. */ 91 int __system_property_read(const prop_info* __pi, char* __name, char* __value); 92 /* Deprecated. Use __system_property_read_callback instead. */ 93 int __system_property_get(const char* __name, char* __value); 94 /* Deprecated. Use __system_property_foreach instead. */ 95 const prop_info* __system_property_find_nth(unsigned __n); 96 97 __END_DECLS 98 99 #endif 100
