platform_bionic/libc/include/sys/system_properties.h
Josh Gao 2e8e5e60b6 DO NOT MERGE: The future is now.
__INTRODUCED_IN_FUTURE -> __INTRODUCED_IN(26)

Bug: http://b/37437368
Test: treehugger
Change-Id: I601a23da83b65a0cd582cc840ed3856a9031b673
(cherry picked from commit cb302f932a)
2017-04-20 16:57:25 -07:00

102 lines
3.9 KiB
C

/*
* Copyright (C) 2008 The Android Open Source Project
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#ifndef _INCLUDE_SYS_SYSTEM_PROPERTIES_H
#define _INCLUDE_SYS_SYSTEM_PROPERTIES_H
#include <sys/cdefs.h>
#include <stdbool.h>
#include <stddef.h>
#include <stdint.h>
__BEGIN_DECLS
typedef struct prop_info prop_info;
#define PROP_VALUE_MAX 92
/*
* Sets system property `key` to `value`, creating the system property if it doesn't already exist.
*/
int __system_property_set(const char* key, const char* value) __INTRODUCED_IN(12);
/*
* Returns a `prop_info` corresponding system property `name`, or nullptr if it doesn't exist.
* Use __system_property_read_callback to query the current value.
*
* Property lookup is expensive, so it can be useful to cache the result of this function.
*/
const prop_info* __system_property_find(const char* name);
/*
* Calls `callback` with a consistent trio of name, value, and serial number for property `pi`.
*/
void __system_property_read_callback(const prop_info *pi,
void (*callback)(void* cookie, const char *name, const char *value, uint32_t serial),
void* cookie) __INTRODUCED_IN(26);
/*
* Passes a `prop_info` for each system property to the provided
* callback. Use __system_property_read_callback() to read the value.
*
* This method is for inspecting and debugging the property system, and not generally useful.
*/
int __system_property_foreach(void (*propfn)(const prop_info* pi, void* cookie), void* cookie)
__INTRODUCED_IN(19);
/*
* Waits for the specific system property identified by `pi` to be updated
* past `old_serial`. Waits no longer than `relative_timeout`, or forever
* if `relaive_timeout` is null.
*
* If `pi` is null, waits for the global serial number instead.
*
* If you don't know the current serial, use 0.
*
* Returns true and updates `*new_serial_ptr` on success, or false if the call
* timed out.
*/
struct timespec;
bool __system_property_wait(const prop_info* pi,
uint32_t old_serial,
uint32_t* new_serial_ptr,
const struct timespec* relative_timeout)
__INTRODUCED_IN(26);
/* Deprecated. In Android O and above, there's no limit on property name length. */
#define PROP_NAME_MAX 32
/* Deprecated. Use __system_property_read_callback instead. */
int __system_property_read(const prop_info* pi, char* name, char* value);
/* Deprecated. Use __system_property_read_callback instead. */
int __system_property_get(const char* name, char* value);
/* Deprecated. Use __system_property_foreach instead. */
const prop_info* __system_property_find_nth(unsigned n);
__END_DECLS
#endif