// Copyright 2019 The SwiftShader Authors. All Rights Reserved.
//
// 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 "Thread.hpp"

#include <cstdarg>

#if defined(_WIN32)
#   ifndef WIN32_LEAN_AND_MEAN
#       define WIN32_LEAN_AND_MEAN
#   endif
#   include <windows.h>
#elif defined(__APPLE__)
#   include <pthread.h>
#   include <mach/thread_act.h>
#   include <unistd.h>
#else
#   include <pthread.h>
#   include <unistd.h>
#endif

namespace yarn {

#if defined(_WIN32)

void Thread::setName(const char* fmt, ...)
{
    static auto setThreadDescription = reinterpret_cast<HRESULT(WINAPI*)(HANDLE, PCWSTR)>(GetProcAddress(GetModuleHandle("kernelbase.dll"), "SetThreadDescription"));
    if (setThreadDescription == nullptr)
    {
        return;
    }

    char name[1024];
    va_list vararg;
    va_start(vararg, fmt);
    vsnprintf(name, sizeof(name), fmt, vararg);
    va_end(vararg);

    wchar_t wname[1024];
    mbstowcs(wname, name, 1024);
    setThreadDescription(GetCurrentThread(), wname);
}

unsigned int Thread::numLogicalCPUs()
{
    DWORD_PTR processAffinityMask = 1;
    DWORD_PTR systemAffinityMask = 1;

    GetProcessAffinityMask(GetCurrentProcess(), &processAffinityMask, &systemAffinityMask);

    auto count = 0;
    while (processAffinityMask > 0)
    {
        if (processAffinityMask & 1)
        {
            count++;
        }

        processAffinityMask >>= 1;
    }
    return count;
}

#else

void Thread::setName(const char* fmt, ...)
{
    char name[1024];
    va_list vararg;
    va_start(vararg, fmt);
    vsnprintf(name, sizeof(name), fmt, vararg);
    va_end(vararg);

#if defined(__APPLE__)
    pthread_setname_np(name);
#else
    pthread_setname_np(pthread_self(), name);
#endif
}

unsigned int Thread::numLogicalCPUs()
{
    return sysconf(_SC_NPROCESSORS_ONLN);
}

#endif

} // namespace yarn