platform_system_core/base/liblog_symbols.cpp
Tom Cherry 0391a879f7 Move minimum log priority from libbase to liblog
See the previous commit moving SetLogger and SetAborter to liblog for
motivation.

This creates more harmony between the two mechanisms in libbase and
liblog for checking loggability.
Currently:
1) libbase filters all messages based on its minimum log priority. For
   example, if minimum log priority in libbase remained at its
   default, but a tag was specifically opted into DEBUG logs via
   log.tag.<tag>, libbase would not print this log.
2) liblog ignores libbase's minimum log priority.  For example if a
   process called SetMinimumLogPriority(WARNING) but used a library
   that logged via liblog's ALOGI macro, that log would still be
   printed even though the process intends on filtering out those INFO
   messages.

With this change:
1) If both a minimum log priority and a priority through log.tag.<tag>
   are set, then the lower of the two values is used.
2) If only one or the other is set, then that value is used.  This
   fixes the two issues described above.
3) If neither of these values are set, then the default of using INFO
   is unchanged.

Bug: 116329414
Bug: 119867234
Test: libbase and liblog minimum log priority tests
Change-Id: Icb49b30b9d93bf797470e23730ae9e537931bb6c
2020-01-21 12:14:43 -08:00

83 lines
2.9 KiB
C++

/*
* Copyright (C) 2020 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "liblog_symbols.h"
#if defined(__ANDROID__) && !defined(NO_LIBLOG_DLSYM)
#include <dlfcn.h>
#endif
namespace android {
namespace base {
#if defined(__ANDROID__) && !defined(NO_LIBLOG_DLSYM)
const std::optional<LibLogFunctions>& GetLibLogFunctions() {
static std::optional<LibLogFunctions> liblog_functions = []() -> std::optional<LibLogFunctions> {
void* liblog_handle = dlopen("liblog.so", RTLD_NOW);
if (liblog_handle == nullptr) {
return {};
}
LibLogFunctions real_liblog_functions = {};
#define DLSYM(name) \
real_liblog_functions.name = \
reinterpret_cast<decltype(LibLogFunctions::name)>(dlsym(liblog_handle, #name)); \
if (real_liblog_functions.name == nullptr) { \
return {}; \
}
DLSYM(__android_log_set_logger)
DLSYM(__android_log_write_logger_data)
DLSYM(__android_log_logd_logger)
DLSYM(__android_log_stderr_logger)
DLSYM(__android_log_set_aborter)
DLSYM(__android_log_call_aborter)
DLSYM(__android_log_default_aborter)
DLSYM(__android_log_set_minimum_priority);
DLSYM(__android_log_get_minimum_priority);
#undef DLSYM
return real_liblog_functions;
}();
return liblog_functions;
}
#else
const std::optional<LibLogFunctions>& GetLibLogFunctions() {
static std::optional<LibLogFunctions> liblog_functions = []() -> std::optional<LibLogFunctions> {
return LibLogFunctions{
.__android_log_set_logger = __android_log_set_logger,
.__android_log_write_logger_data = __android_log_write_logger_data,
.__android_log_logd_logger = __android_log_logd_logger,
.__android_log_stderr_logger = __android_log_stderr_logger,
.__android_log_set_aborter = __android_log_set_aborter,
.__android_log_call_aborter = __android_log_call_aborter,
.__android_log_default_aborter = __android_log_default_aborter,
.__android_log_set_minimum_priority = __android_log_set_minimum_priority,
.__android_log_get_minimum_priority = __android_log_get_minimum_priority,
};
}();
return liblog_functions;
}
#endif
} // namespace base
} // namespace android