Added basic game save function, doesn't save much yet, but implements version comparison of binary saves for compatibility

src/game.c

@@ -4,6 +4,7 @@
 #include <SDL3_ttf/SDL_ttf.h>
 #include <stdio.h>
 #include <akerror.h>
+#include <semver.h>
 
 #include <akgl/game.h>
 #include <akgl/controller.h>
@@ -127,34 +128,61 @@ akerr_ErrorContext AKERR_NOIGNORE *akgl_game_save(char *fpath)
     PREPARE_ERROR(errctx);
 
     FAIL_ZERO_RETURN(errctx, fpath, AKERR_NULLPOINTER, "NULL file path");
-    fp = fopen(fpath, "rb");
+    fp = fopen(fpath, "wb");
+    FAIL_ZERO_RETURN(errctx, fp, errno, "%s", fpath);
+    fwrite(&game, 1, sizeof(akgl_Game), fp);
     fclose(fp);
-    SUCCEED(errctx); // SUCCEED_NORETURN if in main().
+    SUCCEED_RETURN(errctx); // SUCCEED_NORETURN if in main().
 }
 
 akerr_ErrorContext AKERR_NOIGNORE *akgl_game_load(char *fpath)
 {
     FILE *fp = NULL;
-    char version[32];
+    char versionstr[32];
+    semver_t current_version = {};
+    semver_t compare_version = {};
     
     PREPARE_ERROR(errctx);
     FAIL_ZERO_RETURN(errctx, fpath, AKERR_NULLPOINTER, "NULL file path");
-    fp = fopen(fpath, "rb");
-    FAIL_ZERO_RETURN(
-	errctx,
-	(fread((void *)&version, 1, 32, fp) < 32),
-	AKERR_IO,
+    
+    ATTEMPT {
+	FAIL_NONZERO_BREAK(
+	    errctx,
+	    semver_parse((const char *)&game.version, &current_version),
+	    AKERR_VALUE,
+	    "Invalid semantic version in current game: %s",
+	    (char *)&current_version);
+	fp = fopen(fpath, "rb");
+	FAIL_NONZERO_BREAK(
+	    errctx,
+	    (fread((void *)&versionstr, 1, 32, fp) < 32),
+	    AKERR_IO,
+	    "Corrupt save file");
+	FAIL_NONZERO_BREAK(
+	    errctx,
+	    semver_parse((const char *)&versionstr, &compare_version),
+	    AKERR_VALUE,
+	    "Invalid semantic version in save game: %s",
+	    (char *)&versionstr);
+	FAIL_ZERO_BREAK(
+	    errctx,
+	    semver_satisfies(compare_version, current_version, "^"),
+	    AKERR_API,
+	    "Incompatible save game version");
+	rewind(fp);
+	FAIL_NONZERO_BREAK(
+	    errctx,
+	    (fread((void *)&game, 1, sizeof(akgl_Game), fp) < sizeof(akgl_Game)),
+	    AKERR_IO,
 	"Corrupt save file");
-    FAIL_ZERO_RETURN(
-	errctx,
-	strncmp((char *)&game.version, (char *)&version, 32),
-	AKERR_API,
-	"Save game can not be loaded, it is from an incompatible version");
-    rewind(fp);
-    FAIL_ZERO_RETURN(
-	errctx,
-	(fread((void *)&game, 1, sizeof(akgl_Game), fp) < sizeof(akgl_Game)),
-	AKERR_IO,
-	"Corrupt save file");
-    SUCCEED(errctx);
+    } CLEANUP {
+	if ( fp != NULL ) {
+	    fclose(fp);
+	}
+	semver_free(&current_version);
+	semver_free(&compare_version);
+    } PROCESS(errctx) {
+    } FINISH(errctx, true);
+    
+    SUCCEED_RETURN(errctx);
 }