GB, GBA Core: Fix memory leak if reloading debug symbols

Also fix loading an ELF if the current seek is not 0

CHANGES

@@ -4,6 +4,7 @@ Emulation fixes:
  - GBA GPIO: Fix gyro read-out start (fixes mgba.io/i/3141)
  - GBA SIO: Fix MULTI mode SIOCNT bit 7 writes on secondary GBAs (fixes mgba.io/i/3110)
 Other fixes:
+ - GB, GBA Core: Fix memory leak if reloading debug symbols
  - GBA Audio: Fix crash if audio FIFOs and timers get out of sync
  - GBA Audio: Fix crash in audio subsampling if timing lockstep breaks
  - GBA Memory: Let raw access read high MMIO addresses

src/gb/core.c

@@ -1050,7 +1050,9 @@ static void _GBCoreDetachDebugger(struct mCore* core) {
 }
 
 static void _GBCoreLoadSymbols(struct mCore* core, struct VFile* vf) {
-	core->symbolTable = mDebuggerSymbolTableCreate();
+	if (!core->symbolTable) {
+		core->symbolTable = mDebuggerSymbolTableCreate();
+	}
 #if !defined(MINIMAL_CORE) || MINIMAL_CORE < 2
 	if (!vf && core->dirs.base) {
 		vf = mDirectorySetOpenSuffix(&core->dirs, core->dirs.base, ".sym", O_RDONLY);

src/gba/core.c

@@ -1113,7 +1113,14 @@ static void _GBACoreDetachDebugger(struct mCore* core) {
 
 static void _GBACoreLoadSymbols(struct mCore* core, struct VFile* vf) {
 	bool closeAfter = false;
-	core->symbolTable = mDebuggerSymbolTableCreate();
+	if (!core->symbolTable) {
+		core->symbolTable = mDebuggerSymbolTableCreate();
+	}
+	off_t seek;
+	if (vf) {
+		seek = vf->seek(vf, 0, SEEK_CUR);
+		vf->seek(vf, 0, SEEK_SET);
+	}
 #if !defined(MINIMAL_CORE) || MINIMAL_CORE < 2
 #ifdef USE_ELF
 	if (!vf && core->dirs.base) {
@@ -1143,6 +1150,8 @@ static void _GBACoreLoadSymbols(struct mCore* core, struct VFile* vf) {
 	}
 	if (closeAfter) {
 		vf->close(vf);
+	} else {
+		vf->seek(vf, seek, SEEK_SET);
 	}
 }