Safer file loading, better showing of fatal errors (drop out of double buffering)

!TheEsc/c/Graphics

@@ -12,6 +12,7 @@ extern unsigned char *tilebuffer;
 
 int screen = 1;
 
+extern void screen_nobuffer();
 // Loads sprite file into buffer
 void load_sprites(char* filename, unsigned char **buffername)
 {
@@ -34,7 +35,8 @@ void load_sprites(char* filename, unsigned char **buffername)
 
   // Stops us trying to mallocsomething mad if file is too big.
   if(length > 200000)
-  {         
+  {
+    screen_nobuffer();
     printf("Sprite file %s seems unreasonably large at %i bytes",filename, length);
     exit(0);
   }
@@ -44,6 +46,7 @@ void load_sprites(char* filename, unsigned char **buffername)
 
   if(buffername==NULL)
   {
+    screen_nobuffer();
     printf("Couldn't malloc %i bytes for sprite buffer",length);
     exit(0);
   }
@@ -85,6 +88,7 @@ void display_mode(int mode)
   inreg.r[1] = (pitch * height * 2) - outreg.r[1];
   if (_kernel_swi(OS_ChangeDynamicArea, &inreg, &outreg) != NULL)
   {
+    screen_nobuffer();
     printf("Couldn't OS_ChangeDynamicArea");
     exit(0);
   }

!TheEsc/c/Mission2

@@ -46,6 +46,13 @@ void game2_loadmap(char* filename)
   // Length will be in R4 if it exists
   length = outreg.r[4];
 
+  if(length > sizeof(map[0]))
+  {
+    screen_nobuffer();
+    printf("Map exceeds %d bytes (%d bytes)",sizeof(map[0]),length);
+    exit(0);
+  }
+  
   // Attempt to get file info
   inreg.r[0] = 16;
   inreg.r[1] = (int) filename;