platform_bionic/libc/system_properties/prop_info.cpp
Tom Cherry e275d6d72d Split properties into their own class to make testing better
Reinitializing system properties can result in crashes later in the
program, and is generally not recommended or even supported.  This
change moves the actual logic for system properties into a class that
can be tested in isolation, without reinitializing the actual system
property area used in libc.

Bug: 62197783
Test: boot devices, ensure properties work
Test: system property unit tests and benchmarks
Change-Id: I9ae6e1b56c62f51a4d3fdb5b62b8926cef545649
2017-12-18 15:17:55 -08:00

55 lines
2.4 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.
*/
#include "system_properties/prop_info.h"
#include <string.h>
constexpr static const char kLongLegacyError[] =
"Must use __system_property_read_callback() to read";
static_assert(sizeof(kLongLegacyError) < prop_info::kLongLegacyErrorBufferSize,
"Error message for long properties read by legacy libc must fit within 56 chars");
prop_info::prop_info(const char* name, uint32_t namelen, const char* value, uint32_t valuelen) {
memcpy(this->name, name, namelen);
this->name[namelen] = '\0';
atomic_init(&this->serial, valuelen << 24);
memcpy(this->value, value, valuelen);
this->value[valuelen] = '\0';
}
prop_info::prop_info(const char* name, uint32_t namelen, uint32_t long_offset) {
memcpy(this->name, name, namelen);
this->name[namelen] = '\0';
auto error_value_len = sizeof(kLongLegacyError) - 1;
atomic_init(&this->serial, error_value_len << 24 | kLongFlag);
memcpy(this->long_property.error_message, kLongLegacyError, sizeof(kLongLegacyError));
this->long_property.offset = long_offset;
}