From c714e8cb6bbf86b3430cb94159374cf83ed52df4 Mon Sep 17 00:00:00 2001 From: Exzap <13877693+Exzap@users.noreply.github.com> Date: Thu, 30 Jan 2025 03:32:24 +0100 Subject: [PATCH] coreinit: Time to tick conversion is unsigned The result is treated as signed in most cases, but the calculation uses unsigned arithmetic. As a concrete example where this matters, DS VC passes -1 (2^64-1) to OSWaitEventWithTimeout which internally causes an overflow. But only with unsigned arithmetic this will result in a large positive number that behaves like the intended infinite timeout. With signed arithmetic the result is negative and the events will timeout immediately. --- src/Cafe/OS/libs/coreinit/coreinit_Synchronization.cpp | 8 +++----- src/Cafe/OS/libs/coreinit/coreinit_Time.h | 4 ++-- 2 files changed, 5 insertions(+), 7 deletions(-) diff --git a/src/Cafe/OS/libs/coreinit/coreinit_Synchronization.cpp b/src/Cafe/OS/libs/coreinit/coreinit_Synchronization.cpp index c144c384..e81cc577 100644 --- a/src/Cafe/OS/libs/coreinit/coreinit_Synchronization.cpp +++ b/src/Cafe/OS/libs/coreinit/coreinit_Synchronization.cpp @@ -73,8 +73,6 @@ namespace coreinit } } - uint64 coreinit_getOSTime(); - bool OSWaitEventWithTimeout(OSEvent* event, uint64 timeout) { __OSLockScheduler(); @@ -95,14 +93,14 @@ namespace coreinit // workaround for a bad implementation in some Unity games (like Qube Directors Cut, see FEventWiiU::Wait) // where the the return value of OSWaitEventWithTimeout is ignored and instead the game measures the elapsed time to determine if a timeout occurred - timeout = timeout * 98ULL / 100ULL; // 98% (we want the function to return slightly before the actual timeout) + if (timeout < 0x00FFFFFFFFFFFFFFULL) + timeout = timeout * 98ULL / 100ULL; // 98% (we want the function to return slightly before the actual timeout) WaitEventWithTimeoutData data; data.thread = OSGetCurrentThread(); data.threadQueue = &event->threadQueue; data.hasTimeout = false; - - auto hostAlarm = coreinit::OSHostAlarmCreate(coreinit::coreinit_getOSTime() + coreinit::EspressoTime::ConvertNsToTimerTicks(timeout), 0, _OSWaitEventWithTimeoutHandler, &data); + auto hostAlarm = coreinit::OSHostAlarmCreate(OSGetTime() + coreinit::EspressoTime::ConvertNsToTimerTicks(timeout), 0, _OSWaitEventWithTimeoutHandler, &data); event->threadQueue.queueAndWait(OSGetCurrentThread()); coreinit::OSHostAlarmDestroy(hostAlarm); if (data.hasTimeout) diff --git a/src/Cafe/OS/libs/coreinit/coreinit_Time.h b/src/Cafe/OS/libs/coreinit/coreinit_Time.h index 3aa92b99..37bd5f88 100644 --- a/src/Cafe/OS/libs/coreinit/coreinit_Time.h +++ b/src/Cafe/OS/libs/coreinit/coreinit_Time.h @@ -40,12 +40,12 @@ namespace coreinit inline TimerTicks ConvertNsToTimerTicks(uint64 ns) { - return ((GetTimerClock() / 31250LL) * ((TimerTicks)ns) / 32000LL); + return static_cast((static_cast(GetTimerClock()) / 31250ULL) * (ns) / 32000ULL); } inline TimerTicks ConvertMsToTimerTicks(uint64 ms) { - return (TimerTicks)ms * GetTimerClock() / 1000LL; + return static_cast(ms * static_cast(GetTimerClock()) / 1000ULL); } };