From 4c771227f5fe93cac7460af627e4c0d0ad5631d9 Mon Sep 17 00:00:00 2001
From: Andrew Kesterson <andrew@aklabs.net>
Date: Fri, 8 May 2026 23:48:35 -0400
Subject: [PATCH] Encode library version and game version into savegame files
 and check them both

---
 include/akgl/SDL_GameControllerDB.h |  2 +-
 include/akgl/game.h                 |  7 +++--
 src/game.c                          | 48 +++++++++++++++++++++--------
 3 files changed, 41 insertions(+), 16 deletions(-)

diff --git a/include/akgl/SDL_GameControllerDB.h b/include/akgl/SDL_GameControllerDB.h
index 87fc184..57c03d5 100644
--- a/include/akgl/SDL_GameControllerDB.h
+++ b/include/akgl/SDL_GameControllerDB.h
@@ -1,7 +1,7 @@
 #ifndef _SDL_GAMECONTROLLERDB_H_
 #define _SDL_GAMECONTROLLERDB_H_
 
-// Taken from https://raw.githubusercontent.com/mdqinc/SDL_GameControllerDB/refs/heads/master/gamecontrollerdb.txt on Fri May  8 11:02:47 PM EDT 2026
+// Taken from https://raw.githubusercontent.com/mdqinc/SDL_GameControllerDB/refs/heads/master/gamecontrollerdb.txt on Fri May  8 11:47:47 PM EDT 2026
 
 #define AKGL_SDL_GAMECONTROLLER_DB_LEN         2227
 
diff --git a/include/akgl/game.h b/include/akgl/game.h
index 06a320e..0200adc 100644
--- a/include/akgl/game.h
+++ b/include/akgl/game.h
@@ -6,8 +6,10 @@
 #include <SDL3_mixer/SDL_mixer.h>
 #include "tilemap.h"
 
-#define AKGL_GAME_AUDIO_TRACK_BGM       1
-#define AKGL_GAME_AUDIO_MAX_TRACKS      64
+#define AKGL_VERSION                     "0.1.0"
+
+#define AKGL_GAME_AUDIO_TRACK_BGM        1
+#define AKGL_GAME_AUDIO_MAX_TRACKS       64
 
 #define AKGL_TIME_ONESEC_NS              1000000000
 #define AKGL_TIME_ONESEC_MS              1000000
@@ -25,6 +27,7 @@ typedef struct {
 } akgl_GameState;
 
 typedef struct {
+    char libversion[32];
     char version[32];
     char name[256];
     char uri[256];
diff --git a/src/game.c b/src/game.c
index f2318bc..e226778 100644
--- a/src/game.c
+++ b/src/game.c
@@ -34,6 +34,7 @@ akerr_ErrorContext AKERR_NOIGNORE *akgl_game_init()
     int i = 0;
     PREPARE_ERROR(errctx);
     ATTEMPT {
+	strncpy((char *)&game.libversion, AKGL_VERSION, 32);
 	game.gameStartTime = SDL_GetTicksNS();
 	game.lastIterTime = game.gameStartTime;
 	game.lastFPSTime = game.gameStartTime;
@@ -135,24 +136,23 @@ akerr_ErrorContext AKERR_NOIGNORE *akgl_game_save(char *fpath)
     SUCCEED_RETURN(errctx); // SUCCEED_NORETURN if in main().
 }
 
-akerr_ErrorContext AKERR_NOIGNORE *akgl_game_load(char *fpath)
+akerr_ErrorContext AKERR_NOIGNORE *akgl_game_load_versioncmp(FILE *fp, const char *versiontype, char *curversion)
 {
-    FILE *fp = NULL;
     char versionstr[32];
     semver_t current_version = {};
     semver_t compare_version = {};
-    
     PREPARE_ERROR(errctx);
-    FAIL_ZERO_RETURN(errctx, fpath, AKERR_NULLPOINTER, "NULL file path");
+    FAIL_ZERO_RETURN(errctx, fp, AKERR_NULLPOINTER, "NULL file pointer");
     
     ATTEMPT {
+	// Check save game library version	
 	FAIL_NONZERO_BREAK(
 	    errctx,
-	    semver_parse((const char *)&game.version, &current_version),
+	    semver_parse((const char *)curversion, &current_version),
 	    AKERR_VALUE,
-	    "Invalid semantic version in current game: %s",
-	    (char *)&current_version);
-	fp = fopen(fpath, "rb");
+	    "Invalid semantic %s version in current game: %s",
+	    versiontype,
+	    (char *)curversion);
 	FAIL_NONZERO_BREAK(
 	    errctx,
 	    (fread((void *)&versionstr, 1, 32, fp) < 32),
@@ -162,13 +162,37 @@ akerr_ErrorContext AKERR_NOIGNORE *akgl_game_load(char *fpath)
 	    errctx,
 	    semver_parse((const char *)&versionstr, &compare_version),
 	    AKERR_VALUE,
-	    "Invalid semantic version in save game: %s",
+	    "Invalid semantic %s version in save game: %s",
+	    versiontype,
 	    (char *)&versionstr);
 	FAIL_ZERO_BREAK(
 	    errctx,
-	    semver_satisfies(compare_version, current_version, "^"),
+	    semver_satisfies(compare_version, current_version, "="),
 	    AKERR_API,
-	    "Incompatible save game version");
+	    "Incompatible save game %s version (%s ^ %s)",
+	    versiontype,
+	    curversion,
+	    (char *)&versionstr);
+    } CLEANUP {
+	semver_free(&current_version);
+	semver_free(&compare_version);
+    } PROCESS(errctx) {
+    } FINISH(errctx, true);
+    SUCCEED_RETURN(errctx);
+}
+
+akerr_ErrorContext AKERR_NOIGNORE *akgl_game_load(char *fpath)
+{
+    FILE *fp = NULL;
+    
+    PREPARE_ERROR(errctx);
+    FAIL_ZERO_RETURN(errctx, fpath, AKERR_NULLPOINTER, "NULL file path");
+    
+    ATTEMPT {
+	fp = fopen(fpath, "rb");
+	FAIL_ZERO_BREAK(errctx, fp, errno, "%s", fpath);
+	CATCH(errctx, akgl_game_load_versioncmp(fp, "library", (char *)AKGL_VERSION));
+	CATCH(errctx, akgl_game_load_versioncmp(fp, "game", (char *)&game.version));
 	rewind(fp);
 	FAIL_NONZERO_BREAK(
 	    errctx,
@@ -179,8 +203,6 @@ akerr_ErrorContext AKERR_NOIGNORE *akgl_game_load(char *fpath)
 	if ( fp != NULL ) {
 	    fclose(fp);
 	}
-	semver_free(&current_version);
-	semver_free(&compare_version);
     } PROCESS(errctx) {
     } FINISH(errctx, true);