| /* |
| * 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. |
| */ |
| |
| #pragma once |
| |
| #include <sys/param.h> |
| #include <sys/system_properties.h> |
| |
| #include "contexts.h" |
| #include "contexts_pre_split.h" |
| #include "contexts_serialized.h" |
| #include "contexts_split.h" |
| |
| class SystemProperties { |
| public: |
| friend struct LocalPropertyTestState; |
| friend class SystemPropertiesTest; |
| // Note that system properties are initialized before libc calls static initializers, so |
| // doing any initialization in this constructor is an error. Even a Constructor that zero |
| // initializes this class will clobber the previous property initialization. |
| // We rely on the static SystemProperties in libc to be placed in .bss and zero initialized. |
| SystemProperties() = default; |
| // Special constructor for testing that also zero initializes the important members. |
| explicit SystemProperties(bool initialized) : initialized_(initialized) { |
| } |
| |
| BIONIC_DISALLOW_COPY_AND_ASSIGN(SystemProperties); |
| |
| bool Init(const char* filename); |
| bool Reload(bool load_default_path); |
| bool AreaInit(const char* filename, bool* fsetxattr_failed); |
| bool AreaInit(const char* filename, bool* fsetxattr_failed, bool load_default_path); |
| uint32_t AreaSerial(); |
| const prop_info* Find(const char* name); |
| int Read(const prop_info* pi, char* name, char* value); |
| void ReadCallback(const prop_info* pi, |
| void (*callback)(void* cookie, const char* name, const char* value, |
| uint32_t serial), |
| void* cookie); |
| int Get(const char* name, char* value); |
| int Update(prop_info* pi, const char* value, unsigned int len); |
| int Add(const char* name, unsigned int namelen, const char* value, unsigned int valuelen); |
| uint32_t WaitAny(uint32_t old_serial); |
| bool Wait(const prop_info* pi, uint32_t old_serial, uint32_t* new_serial_ptr, |
| const timespec* relative_timeout); |
| const prop_info* FindNth(unsigned n); |
| int Foreach(void (*propfn)(const prop_info* pi, void* cookie), void* cookie); |
| |
| private: |
| uint32_t ReadMutablePropertyValue(const prop_info* pi, char* value); |
| |
| // We don't want to use new or malloc in properties (b/31659220), and we don't want to waste a |
| // full page by using mmap(), so we set aside enough space to create any context of the three |
| // contexts. |
| static constexpr size_t kMaxContextsAlign = |
| MAX(alignof(ContextsSerialized), MAX(alignof(ContextsSplit), alignof(ContextsPreSplit))); |
| static constexpr size_t kMaxContextsSize = |
| MAX(sizeof(ContextsSerialized), MAX(sizeof(ContextsSplit), sizeof(ContextsPreSplit))); |
| alignas(kMaxContextsAlign) char contexts_data_[kMaxContextsSize]; |
| alignas(kMaxContextsAlign) char appcompat_override_contexts_data_[kMaxContextsSize]; |
| Contexts* contexts_; |
| // See http://b/291816546#comment#3 for more explanation of appcompat_override |
| Contexts* appcompat_override_contexts_; |
| |
| bool InitContexts(bool load_default_path); |
| |
| bool initialized_; |
| PropertiesFilename properties_filename_; |
| PropertiesFilename appcompat_filename_; |
| }; |