From 4a0305eec8e4646d171ccc527cb706175609a3ba Mon Sep 17 00:00:00 2001
From: Monster Iestyn <iestynjealous@ntlworld.com>
Date: Fri, 23 Feb 2018 20:40:19 +0000
Subject: [PATCH] more I_GetFreeMem fixes: don't attempt to set *total to 0L if
 total itself is NULL

---
 src/sdl/i_system.c | 22 ++++++++++++++--------
 1 file changed, 14 insertions(+), 8 deletions(-)

diff --git a/src/sdl/i_system.c b/src/sdl/i_system.c
index 4675ac14..e86a39ca 100644
--- a/src/sdl/i_system.c
+++ b/src/sdl/i_system.c
@@ -2729,20 +2729,23 @@ UINT32 I_GetFreeMem(UINT32 *total)
 	};
 	if ((kd = kvm_open(NULL, NULL, NULL, O_RDONLY, "kvm_open")) == NULL)
 	{
-		*total = 0L;
+		if (total)
+			*total = 0L;
 		return 0;
 	}
 	if (kvm_nlist(kd, namelist) != 0)
 	{
 		kvm_close (kd);
-		*total = 0L;
+		if (total)
+			*total = 0L;
 		return 0;
 	}
 	if (kvm_read(kd, namelist[X_SUM].n_value, &sum,
 		sizeof (sum)) != sizeof (sum))
 	{
 		kvm_close(kd);
-		*total = 0L;
+		if (total)
+			*total = 0L;
 		return 0;
 	}
 	kvm_close(kd);
@@ -2789,25 +2792,28 @@ UINT32 I_GetFreeMem(UINT32 *total)
 	if (n < 0)
 	{
 		// Error
-		*total = 0L;
+		if (total)
+			*total = 0L;
 		return 0;
 	}
 
 	buf[n] = '\0';
-	if (NULL == (memTag = strstr(buf, MEMTOTAL)))
+	if ((memTag = strstr(buf, MEMTOTAL)) == NULL)
 	{
 		// Error
-		*total = 0L;
+		if (total)
+			*total = 0L;
 		return 0;
 	}
 
 	memTag += sizeof (MEMTOTAL);
 	totalKBytes = atoi(memTag);
 
-	if (NULL == (memTag = strstr(buf, MEMFREE)))
+	if ((memTag = strstr(buf, MEMFREE)) == NULL)
 	{
 		// Error
-		*total = 0L;
+		if (total)
+			*total = 0L;
 		return 0;
 	}