Make room names own their own memory

This makes it so room names are no longer pointers to someone else's
memory, and instead to set them you use `mapclass::setroomname`. If the
string is short enough to fit in a static, no-alloc buffer, then it gets
copied there. Otherwise, a new heap allocation is made that duplicates
the string, and the new pointer is used instead.

This makes it possible for room names to contain arbitrary data whose
origin is temporary (e.g. from a script command that could be added in
the future).

desktop_version/src/Map.cpp

@@ -1,6 +1,7 @@
 #define MAP_DEFINITION
 #include "Map.h"
 
+#include "Alloc.h"
 #include "Constants.h"
 #include "CustomLevels.h"
 #include "Entity.h"
@@ -80,10 +81,18 @@ mapclass::mapclass(void)
 
     nexttowercolour_set = false;
 
-    roomname = "";
+    setroomname("");
     hiddenname = "";
 }
 
+static char roomname_static[SCREEN_WIDTH_CHARS];
+static char* roomname_heap;
+
+void mapclass::destroy(void)
+{
+    VVV_free(roomname_heap);
+}
+
 //Areamap starts at 100,100 and extends 20x20
 const int mapclass::areamap[] = {
     1,2,2,2,2,2,2,2,0,3,0,0,0,4,4,4,4,4,4,4,
@@ -163,6 +172,25 @@ void mapclass::settrinket(int x, int y)
     shinytrinkets.push_back(temp);
 }
 
+void mapclass::setroomname(const char* name)
+{
+    VVV_free(roomname_heap);
+
+    const size_t size = SDL_strlcpy(
+        roomname_static, name, sizeof(roomname_static)
+    ) + 1;
+    roomname = roomname_static;
+
+    if (size > sizeof(roomname_static))
+    {
+        roomname_heap = SDL_strdup(name);
+        if (roomname_heap != NULL)
+        {
+            roomname = roomname_heap;
+        }
+    }
+}
+
 void mapclass::resetmap(void)
 {
     //clear the explored area of the map
@@ -1386,7 +1414,7 @@ void mapclass::loadlevel(int rx, int ry)
     obj.customplatformtile=0;
     obj.vertplatforms = false;
     obj.horplatforms = false;
-    roomname = "";
+    setroomname("");
     hiddenname = "";
     background = 1;
     warpx = false;
@@ -1518,7 +1546,7 @@ void mapclass::loadlevel(int rx, int ry)
         extrarow = 1;
         const short* tmap = otherlevel.loadlevel(rx, ry);
         copy_short_to_int(contents, tmap, SDL_arraysize(contents));
-        roomname = otherlevel.roomname;
+        setroomname(otherlevel.roomname);
         hiddenname = otherlevel.hiddenname;
         tileset = otherlevel.roomtileset;
         break;
@@ -1527,7 +1555,7 @@ void mapclass::loadlevel(int rx, int ry)
     {
         const short* tmap = lablevel.loadlevel(rx, ry);
         copy_short_to_int(contents, tmap, SDL_arraysize(contents));
-        roomname = lablevel.roomname;
+        setroomname(lablevel.roomname);
         tileset = 1;
         background = 2;
         graphics.rcol = lablevel.rcol;
@@ -1540,7 +1568,7 @@ void mapclass::loadlevel(int rx, int ry)
         graphics.towerbg.scrolldir = 0;
         setbgobjlerp(graphics.towerbg);
 
-        roomname = "The Tower";
+        setroomname("The Tower");
         tileset = 1;
         background = 3;
         towermode = true;
@@ -1574,7 +1602,7 @@ void mapclass::loadlevel(int rx, int ry)
     {
         const short* tmap = warplevel.loadlevel(rx, ry);
         copy_short_to_int(contents, tmap, SDL_arraysize(contents));
-        roomname = warplevel.roomname;
+        setroomname(warplevel.roomname);
         tileset = 1;
         background = 3;
         graphics.rcol = warplevel.rcol;
@@ -1592,7 +1620,7 @@ void mapclass::loadlevel(int rx, int ry)
     {
         const short* tmap = spacestation2.loadlevel(rx, ry);
         copy_short_to_int(contents, tmap, SDL_arraysize(contents));
-        roomname = spacestation2.roomname;
+        setroomname(spacestation2.roomname);
         tileset = 0;
         break;
     }
@@ -1600,7 +1628,7 @@ void mapclass::loadlevel(int rx, int ry)
     {
         const short* tmap = finallevel.loadlevel(rx, ry);
         copy_short_to_int(contents, tmap, SDL_arraysize(contents));
-        roomname = finallevel.roomname;
+        setroomname(finallevel.roomname);
         tileset = 1;
         background = 3;
         graphics.backgrounddrawn = false;
@@ -1630,7 +1658,7 @@ void mapclass::loadlevel(int rx, int ry)
         graphics.towerbg.scrolldir = 1;
         setbgobjlerp(graphics.towerbg);
 
-        roomname = "Panic Room";
+        setroomname("Panic Room");
         tileset = 1;
         background = 3;
         towermode = true;
@@ -1652,7 +1680,7 @@ void mapclass::loadlevel(int rx, int ry)
         graphics.towerbg.scrolldir = 1;
         setbgobjlerp(graphics.towerbg);
 
-        roomname = "Panic Room";
+        setroomname("Panic Room");
         tileset = 1;
         background = 3;
         towermode = true;
@@ -1681,7 +1709,7 @@ void mapclass::loadlevel(int rx, int ry)
         graphics.towerbg.scrolldir = 0;
         setbgobjlerp(graphics.towerbg);
 
-        roomname = "The Final Challenge";
+        setroomname("The Final Challenge");
         tileset = 1;
         background = 3;
         towermode = true;
@@ -1726,7 +1754,7 @@ void mapclass::loadlevel(int rx, int ry)
         graphics.towerbg.scrolldir = 0;
         setbgobjlerp(graphics.towerbg);
 
-        roomname = "The Final Challenge";
+        setroomname("The Final Challenge");
         tileset = 1;
         background = 3;
         towermode = true;
@@ -1759,7 +1787,7 @@ void mapclass::loadlevel(int rx, int ry)
     {
         const short* tmap = finallevel.loadlevel(rx, ry);
         copy_short_to_int(contents, tmap, SDL_arraysize(contents));
-        roomname = finallevel.roomname;
+        setroomname(finallevel.roomname);
         tileset = 2;
         if (rx == 108)
         {
@@ -1842,7 +1870,7 @@ void mapclass::loadlevel(int rx, int ry)
             break;
         }
 
-        roomname = room->roomname.c_str();
+        setroomname(room->roomname.c_str());
         extrarow = 1;
         const int* tmap = cl.loadlevel(rx, ry);
         SDL_memcpy(contents, tmap, sizeof(contents));

desktop_version/src/Map.h

@@ -22,6 +22,7 @@ class mapclass
 {
 public:
     mapclass(void);
+    void destroy(void);
 
     int getwidth(void);
 
@@ -33,6 +34,8 @@ public:
 
     void settrinket(int x, int y);
 
+    void setroomname(const char* name);
+
     void resetmap(void);
 
     void resetnames(void);

desktop_version/src/main.cpp

@@ -755,6 +755,7 @@ static void cleanup(void)
     graphics.destroy_buffers();
     graphics.destroy();
     music.destroy();
+    map.destroy();
     NETWORK_shutdown();
     SDL_Quit();
     FILESYSTEM_deinit();