File 0001-Fix-integer-overflow-during-multiplication... of Package prboom-plus

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File 0001-Fix-integer-overflow-during-multiplication-with-real.patch of Package prboom-plus

From 247c27d7dfe44712975c75a9d741b69cca36d895 Mon Sep 17 00:00:00 2001
From: Jan Engelhardt <jengelh@inai.de>
Date: Tue, 15 Feb 2022 20:28:48 +0100
Subject: [PATCH] Fix integer overflow during multiplication with
 realtic_clock_rate (#476)

When the program has run for about 26 minutes and SDL_GetTicks has
accrued a reasonably large value, multiplication by realtic_clock_rate
overflows "int" on contemporary platforms, manifesting in jagged
motion.

Fixes: v2.6.1um-29-ga7bafe07
Closes #471
---
 prboom2/src/SDL/i_main.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/prboom2/src/SDL/i_main.c b/prboom2/src/SDL/i_main.c
index c0fc0288..a29ccda7 100644
--- prboom2/src/SDL/i_main.c
+++ prboom2/src/SDL/i_main.c
@@ -100,8 +100,8 @@ int ms_to_next_tick;
 
 int I_GetTime_RealTime (void)
 {
-  int t = I_GetTime_MS();
-  int i = t * TICRATE / 1000;
+  int64_t t = I_GetTime_MS();
+  int64_t i = t * TICRATE / 1000;
 
   ms_to_next_tick = (i + 1) * 1000 / TICRATE - t;
   ms_to_next_tick = BETWEEN(0, 1000 / TICRATE, ms_to_next_tick);
@@ -113,8 +113,8 @@ int realtic_clock_rate = 100;
 
 static int I_GetTime_Scaled(void)
 {
-  int t = I_GetTime_MS();
-  int i = t * TICRATE * realtic_clock_rate / 100000;
+  int64_t t = I_GetTime_MS();
+  int64_t i = t * TICRATE * realtic_clock_rate / 100000;
 
   ms_to_next_tick = (i + 1) * 100000 / realtic_clock_rate / TICRATE - t;
   ms_to_next_tick = BETWEEN(0, 100000 / realtic_clock_rate / TICRATE, ms_to_next_tick);
@@ -147,12 +147,12 @@ static int I_TickElapsedTime_FastDemo(void)
 
 static int I_TickElapsedTime_RealTime(void)
 {
-  return I_GetTime_MS() * TICRATE % 1000 * FRACUNIT / 1000;
+  return (int64_t)I_GetTime_MS() * TICRATE % 1000 * FRACUNIT / 1000;
 }
 
 static int I_TickElapsedTime_Scaled(void)
 {
-  return I_GetTime_MS() * realtic_clock_rate * TICRATE / 100 % 1000 * FRACUNIT / 1000;
+  return (int64_t)I_GetTime_MS() * realtic_clock_rate * TICRATE / 100 % 1000 * FRACUNIT / 1000;
 }
 
 int (*I_TickElapsedTime)(void) = I_TickElapsedTime_RealTime;
-- 
2.35.1

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File 0001-Fix-integer-overflow-during-multiplication-with-real.patch of Package prboom-plus

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