From 81210f46af4177958e2c4932c33ddf86b3e96258 Mon Sep 17 00:00:00 2001
From: Alexander Batalov <alex.batalov@gmail.com>
Date: Fri, 10 Feb 2023 11:05:42 +0300
Subject: [PATCH] Fix storing pointers in game global variables

---
 src/game.cc              | 43 +++++++++++++++++++++++++++++++++++++++-
 src/game.h               |  2 ++
 src/interpreter_extra.cc | 23 ++++++++++++++-------
 3 files changed, 60 insertions(+), 8 deletions(-)

diff --git a/src/game.cc b/src/game.cc
index 277e34f..c0ffb89 100644
--- a/src/game.cc
+++ b/src/game.cc
@@ -117,6 +117,9 @@ int _game_user_wants_to_quit = 0;
 // 0x58E940
 MessageList gMiscMessageList;
 
+// CE: Sonora folks like to store objects in global variables.
+static void** gGameGlobalPointers = nullptr;
+
 // 0x442580
 int gameInitWithOptions(const char* windowTitle, bool isMapper, int font, int a4, int argc, char** argv)
 {
@@ -993,7 +996,18 @@ int gameSetGlobalVar(int var, int value)
 // 0x443CC8
 static int gameLoadGlobalVars()
 {
-    return globalVarsRead("data\\vault13.gam", "GAME_GLOBAL_VARS:", &gGameGlobalVarsLength, &gGameGlobalVars);
+    if (globalVarsRead("data\\vault13.gam", "GAME_GLOBAL_VARS:", &gGameGlobalVarsLength, &gGameGlobalVars) != 0) {
+        return -1;
+    }
+
+    gGameGlobalPointers = reinterpret_cast<void**>(internal_malloc(sizeof(*gGameGlobalPointers) * gGameGlobalVarsLength));
+    if (gGameGlobalPointers == nullptr) {
+        return -1;
+    }
+
+    memset(gGameGlobalPointers, 0, sizeof(*gGameGlobalPointers) * gGameGlobalVarsLength);
+
+    return 0;
 }
 
 // 0x443CE8
@@ -1134,6 +1148,11 @@ static void gameFreeGlobalVars()
         internal_free(gGameGlobalVars);
         gGameGlobalVars = NULL;
     }
+
+    if (gGameGlobalPointers != nullptr) {
+        internal_free(gGameGlobalPointers);
+        gGameGlobalPointers = nullptr;
+    }
 }
 
 // 0x443F74
@@ -1492,6 +1511,28 @@ int gameShowDeathDialog(const char* message)
     return rc;
 }
 
+void* gameGetGlobalPointer(int var)
+{
+    if (var < 0 || var >= gGameGlobalVarsLength) {
+        debugPrint("ERROR: attempt to reference global pointer out of range: %d", var);
+        return nullptr;
+    }
+
+    return gGameGlobalPointers[var];
+}
+
+int gameSetGlobalPointer(int var, void* value)
+{
+    if (var < 0 || var >= gGameGlobalVarsLength) {
+        debugPrint("ERROR: attempt to reference global var out of range: %d", var);
+        return -1;
+    }
+
+    gGameGlobalPointers[var] = value;
+
+    return 0;
+}
+
 int GameMode::currentGameMode = 0;
 
 void GameMode::enterGameMode(int gameMode)
diff --git a/src/game.h b/src/game.h
index 4ec43f5..967e291 100644
--- a/src/game.h
+++ b/src/game.h
@@ -38,6 +38,8 @@ void gameUpdateState();
 int showQuitConfirmationDialog();
 
 int gameShowDeathDialog(const char* message);
+void* gameGetGlobalPointer(int var);
+int gameSetGlobalPointer(int var, void* value);
 
 class GameMode {
 public:
diff --git a/src/interpreter_extra.cc b/src/interpreter_extra.cc
index 3a2d929..1cce7b4 100644
--- a/src/interpreter_extra.cc
+++ b/src/interpreter_extra.cc
@@ -1207,16 +1207,19 @@ static void opSetMapVar(Program* program)
 // 0x455950
 static void opGetGlobalVar(Program* program)
 {
-    int data = programStackPopInteger(program);
+    int variable = programStackPopInteger(program);
 
-    int value = -1;
     if (gGameGlobalVarsLength != 0) {
-        value = gameGetGlobalVar(data);
+        void* ptr = gameGetGlobalPointer(variable);
+        if (ptr != nullptr) {
+            programStackPushPointer(program, ptr);
+        } else {
+            programStackPushInteger(program, gameGetGlobalVar(variable));
+        }
     } else {
         scriptError("\nScript Error: %s: op_global_var: no global vars found!", program->name);
+        programStackPushInteger(program, -1);
     }
-
-    programStackPushInteger(program, value);
 }
 
 // set_global_var
@@ -1224,11 +1227,17 @@ static void opGetGlobalVar(Program* program)
 // 0x80C6
 static void opSetGlobalVar(Program* program)
 {
-    int value = programStackPopInteger(program);
+    ProgramValue value = programStackPopValue(program);
     int variable = programStackPopInteger(program);
 
     if (gGameGlobalVarsLength != 0) {
-        gameSetGlobalVar(variable, value);
+        if (value.opcode == VALUE_TYPE_PTR) {
+            gameSetGlobalPointer(variable, value.pointerValue);
+            gameSetGlobalVar(variable, 0);
+        } else {
+            gameSetGlobalPointer(variable, nullptr);
+            gameSetGlobalVar(variable, value.integerValue);
+        }
     } else {
         scriptError("\nScript Error: %s: op_set_global_var: no global vars found!", program->name);
     }