Commit 2379c52849693c6933f8216ba8725d564871784a
2021-10-25T11:04:42
os/2: Don't try to be clever with the 32-bit GetTicks fallback.
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diff --git a/src/timer/os2/SDL_systimer.c b/src/timer/os2/SDL_systimer.c
index ae71b81..14f7b81 100644
--- a/src/timer/os2/SDL_systimer.c
+++ b/src/timer/os2/SDL_systimer.c
@@ -42,10 +42,6 @@ typedef unsigned long long ULLONG;
static ULONG ulTmrFreq = 0;
static ULLONG ullTmrStart = 0;
-/* 32-bit counter fallback...not used if DosTmrQuery* is functioning. */
-static ULONG ulPrevTmr = 0;
-static Uint64 ui64TmrStartOffset = 0; /* Used if 32-bit counter overflows. */
-
void
SDL_TicksInit(void)
{
@@ -64,7 +60,6 @@ SDL_TicksInit(void)
ulTmrFreq = 0; /* Error - use DosQuerySysInfo() for timer. */
DosQuerySysInfo(QSV_MS_COUNT, QSV_MS_COUNT, &ulTmrStart, sizeof (ULONG));
ullTmrStart = (ULLONG) ulTmrStart;
- ulPrevTmr = ulTmrStart;
}
void
@@ -86,15 +81,10 @@ SDL_GetTicks64(void)
DosTmrQueryTime((PQWORD)&ullTmrNow);
ui64Result = (ullTmrNow - ullTmrStart) * 1000 / ulTmrFreq;
} else {
+ /* note that this counter rolls over to 0 every ~49 days. Fix your system so DosTmrQueryTime works if you need to avoid this. */
ULONG ulTmrNow;
DosQuerySysInfo(QSV_MS_COUNT, QSV_MS_COUNT, &ulTmrNow, sizeof (ULONG));
- if ( ((ULLONG) ulTmrNow) < ulPrevTmr ) { /* have we overflowed the 32-bit counter since last check? */
- /* Note that this is incorrect if you went more than ~98 days between calls to SDL_GetTicks64(). */
- /* One could query QSV_TIME_HIGH and QSV_TIME_LOW here to verify, but it's probably not worth it. */
- ui64TmrStartOffset += 0xFFFFFFFF;
- }
- ui64Result = (((Uint64) ulTmrNow) - ullTmrStart) + ui64TmrStartOffset;
- ulPrevTmr = ulTmrNow;
+ ui64Result = (((Uint64) ulTmrNow) - ullTmrStart);
}
return ui64Result;
@@ -105,9 +95,9 @@ SDL_GetPerformanceCounter(void)
{
QWORD qwTmrNow;
- if (ulTmrFreq == 0 || (DosTmrQueryTime(&qwTmrNow) != NO_ERROR))
+ if (ulTmrFreq == 0 || (DosTmrQueryTime(&qwTmrNow) != NO_ERROR)) {
return SDL_GetTicks64();
-
+ }
return *((Uint64 *)&qwTmrNow);
}