yuzu/src/core/hle/kernel/svc/svc_condition_variable.cpp

// SPDX-FileCopyrightText: Copyright 2023 yuzu Emulator Project
// SPDX-License-Identifier: GPL-2.0-or-later

#include "core/core.h"
#include "core/hle/kernel/k_memory_layout.h"
#include "core/hle/kernel/k_process.h"
#include "core/hle/kernel/kernel.h"
#include "core/hle/kernel/svc.h"
#include "core/hle/kernel/svc_results.h"

namespace Kernel::Svc {

/// Wait process wide key atomic
Result WaitProcessWideKeyAtomic(Core::System& system, VAddr address, VAddr cv_key, u32 tag,
                                s64 timeout_ns) {
    LOG_TRACE(Kernel_SVC, "called address={:X}, cv_key={:X}, tag=0x{:08X}, timeout_ns={}", address,
              cv_key, tag, timeout_ns);

    // Validate input.
    if (IsKernelAddress(address)) {
        LOG_ERROR(Kernel_SVC, "Attempted to wait on kernel address (address={:08X})", address);
        return ResultInvalidCurrentMemory;
    }
    if (!Common::IsAligned(address, sizeof(s32))) {
        LOG_ERROR(Kernel_SVC, "Address must be 4 byte aligned (address={:08X})", address);
        return ResultInvalidAddress;
    }

    // Convert timeout from nanoseconds to ticks.
    s64 timeout{};
    if (timeout_ns > 0) {
        const s64 offset_tick(timeout_ns);
        if (offset_tick > 0) {
            timeout = offset_tick + 2;
            if (timeout <= 0) {
                timeout = std::numeric_limits<s64>::max();
            }
        } else {
            timeout = std::numeric_limits<s64>::max();
        }
    } else {
        timeout = timeout_ns;
    }

    // Wait on the condition variable.
    return system.Kernel().CurrentProcess()->WaitConditionVariable(
        address, Common::AlignDown(cv_key, sizeof(u32)), tag, timeout);
}

/// Signal process wide key
void SignalProcessWideKey(Core::System& system, VAddr cv_key, s32 count) {
    LOG_TRACE(Kernel_SVC, "called, cv_key=0x{:X}, count=0x{:08X}", cv_key, count);

    // Signal the condition variable.
    return system.Kernel().CurrentProcess()->SignalConditionVariable(
        Common::AlignDown(cv_key, sizeof(u32)), count);
}

Result WaitProcessWideKeyAtomic64(Core::System& system, uint64_t address, uint64_t cv_key,
                                  uint32_t tag, int64_t timeout_ns) {
    R_RETURN(WaitProcessWideKeyAtomic(system, address, cv_key, tag, timeout_ns));
}

void SignalProcessWideKey64(Core::System& system, uint64_t cv_key, int32_t count) {
    SignalProcessWideKey(system, cv_key, count);
}

Result WaitProcessWideKeyAtomic64From32(Core::System& system, uint32_t address, uint32_t cv_key,
                                        uint32_t tag, int64_t timeout_ns) {
    R_RETURN(WaitProcessWideKeyAtomic(system, address, cv_key, tag, timeout_ns));
}

void SignalProcessWideKey64From32(Core::System& system, uint32_t cv_key, int32_t count) {
    SignalProcessWideKey(system, cv_key, count);
}

} // namespace Kernel::Svc