Qt: Add CoreManager::getExtdata API

include/mgba/core/serialize.h

@@ -36,7 +36,7 @@ struct mStateExtdata {
 	struct mStateExtdataItem data[EXTDATA_MAX];
 };
 
-bool mStateExtdataInit(struct mStateExtdata*);
+void mStateExtdataInit(struct mStateExtdata*);
 void mStateExtdataDeinit(struct mStateExtdata*);
 void mStateExtdataPut(struct mStateExtdata*, enum mStateExtdataTag, struct mStateExtdataItem*);
 bool mStateExtdataGet(struct mStateExtdata*, enum mStateExtdataTag, struct mStateExtdataItem*);
@@ -49,6 +49,7 @@ struct mCore;
 bool mCoreSaveStateNamed(struct mCore* core, struct VFile* vf, int flags);
 bool mCoreLoadStateNamed(struct mCore* core, struct VFile* vf, int flags);
 void* mCoreExtractState(struct mCore* core, struct VFile* vf, struct mStateExtdata* extdata);
+bool mCoreExtractExtdata(struct mCore* core, struct VFile* vf, struct mStateExtdata* extdata);
 
 CXX_GUARD_END
 

src/core/serialize.c

@@ -31,9 +31,8 @@ struct mStateExtdataHeader {
 	int64_t offset;
 };
 
-bool mStateExtdataInit(struct mStateExtdata* extdata) {
+void mStateExtdataInit(struct mStateExtdata* extdata) {
 	memset(extdata->data, 0, sizeof(extdata->data));
-	return true;
 }
 
 void mStateExtdataDeinit(struct mStateExtdata* extdata) {
@@ -43,6 +42,7 @@ void mStateExtdataDeinit(struct mStateExtdata* extdata) {
 			extdata->data[i].clean(extdata->data[i].data);
 		}
 	}
+	memset(extdata->data, 0, sizeof(extdata->data));
 }
 
 void mStateExtdataPut(struct mStateExtdata* extdata, enum mStateExtdataTag tag, struct mStateExtdataItem* item) {
@@ -216,7 +216,7 @@ static int _loadPNGChunkHandler(png_structp png, png_unknown_chunkp chunk) {
 	if (!strcmp((const char*) chunk->name, "gbAs")) {
 		void* state = bundle->state;
 		if (!state) {
-			return 0;
+			return 1;
 		}
 		uLongf len = bundle->stateSize;
 		uncompress((Bytef*) state, &len, chunk->data, chunk->size);
@@ -297,6 +297,54 @@ static void* _loadPNGState(struct mCore* core, struct VFile* vf, struct mStateEx
 	}
 	return state;
 }
+
+static bool _loadPNGExtadata(struct VFile* vf, struct mStateExtdata* extdata) {
+	png_structp png = PNGReadOpen(vf, PNG_HEADER_BYTES);
+	png_infop info = png_create_info_struct(png);
+	png_infop end = png_create_info_struct(png);
+	if (!png || !info || !end) {
+		PNGReadClose(png, info, end);
+		return false;
+	}
+	struct mBundledState bundle = {
+		.stateSize = 0,
+		.state = NULL,
+		.extdata = extdata
+	};
+
+	PNGInstallChunkHandler(png, &bundle, _loadPNGChunkHandler, "gbAs gbAx");
+	bool success = PNGReadHeader(png, info);
+	if (!success) {
+		PNGReadClose(png, info, end);
+		return false;
+	}
+
+	unsigned width = png_get_image_width(png, info);
+	unsigned height = png_get_image_height(png, info);
+	uint32_t* pixels = NULL;
+	pixels = malloc(width * height * 4);
+	if (!pixels) {
+		PNGReadClose(png, info, end);
+		return false;
+	}
+
+	success = PNGReadPixels(png, info, pixels, width, height, width);
+	success = success && PNGReadFooter(png, end);
+	PNGReadClose(png, info, end);
+
+	if (success) {
+		struct mStateExtdataItem item = {
+			.size = width * height * 4,
+			.data = pixels,
+			.clean = free
+		};
+		mStateExtdataPut(extdata, EXTDATA_SCREENSHOT, &item);
+	} else {
+		free(pixels);
+		return false;
+	}
+	return true;
+}
 #endif
 
 bool mCoreSaveStateNamed(struct mCore* core, struct VFile* vf, int flags) {
@@ -425,6 +473,20 @@ void* mCoreExtractState(struct mCore* core, struct VFile* vf, struct mStateExtda
 	return state;
 }
 
+bool mCoreExtractExtdata(struct mCore* core, struct VFile* vf, struct mStateExtdata* extdata) {
+#ifdef USE_PNG
+	if (isPNG(vf)) {
+		return _loadPNGExtadata(vf, extdata);
+	}
+#endif
+	if (!core) {
+		return false;
+	}
+	ssize_t stateSize = core->stateSize(core);
+	vf->seek(vf, stateSize, SEEK_SET);
+	return mStateExtdataDeserialize(extdata, vf);
+}
+
 bool mCoreLoadStateNamed(struct mCore* core, struct VFile* vf, int flags) {
 	struct mStateExtdata extdata;
 	mStateExtdataInit(&extdata);

src/platform/qt/CoreManager.cpp

@@ -7,12 +7,16 @@
 
 #include "CoreController.h"
 #include "LogController.h"
+#include "VFileDevice.h"
 
 #include <QDir>
 
 #ifdef M_CORE_GBA
 #include <mgba/gba/core.h>
 #endif
+#ifdef M_CORE_GB
+#include <mgba/gb/core.h>
+#endif
 
 #include <mgba/core/core.h>
 #include <mgba-util/vfs.h>
@@ -27,6 +31,57 @@ void CoreManager::setMultiplayerController(MultiplayerController* multiplayer) {
 	m_multiplayer = multiplayer;
 }
 
+QByteArray CoreManager::getExtdata(const QString& filename, mStateExtdataTag extdataType) {
+	VFileDevice vf(filename, QIODevice::ReadOnly);
+
+	if (!vf.isOpen()) {
+		return {};
+	}
+
+	mStateExtdata extdata;
+	mStateExtdataInit(&extdata);
+
+	QByteArray bytes;
+	auto extract = [&bytes, &extdata, &vf, extdataType](mCore* core) -> bool {
+		if (mCoreExtractExtdata(core, vf, &extdata)) {
+			mStateExtdataItem extitem;
+			if (!mStateExtdataGet(&extdata, extdataType, &extitem)) {
+				return false;
+			}
+			if (extitem.size) {
+				bytes = QByteArray::fromRawData(static_cast<const char*>(extitem.data), extitem.size);
+			}
+			return true;
+		}
+		return false;
+	};
+
+	bool done = false;
+	struct mCore* core = nullptr;
+#ifdef USE_PNG
+	done = extract(nullptr);
+#endif
+#ifdef M_CORE_GBA
+	if (!done) {
+		core = GBACoreCreate();
+		core->init(core);
+		done = extract(core);
+		core->deinit(core);
+	}
+#endif
+#ifdef M_CORE_GB
+	if (!done) {
+		core = GBCoreCreate();
+		core->init(core);
+		done = extract(core);
+		core->deinit(core);
+	}
+#endif
+
+	mStateExtdataDeinit(&extdata);
+	return bytes;
+}
+
 CoreController* CoreManager::loadGame(const QString& path) {
 	QFileInfo info(path);
 	if (!info.isReadable()) {

src/platform/qt/CoreManager.h

@@ -9,6 +9,8 @@
 #include <QObject>
 #include <QString>
 
+#include <mgba/core/serialize.h>
+
 struct mCoreConfig;
 struct VFile;
 
@@ -25,6 +27,8 @@ public:
 	void setMultiplayerController(MultiplayerController*);
 	void setPreload(bool preload) { m_preload = preload; }
 
+	static QByteArray getExtdata(const QString& filename, mStateExtdataTag extdataType);
+
 public slots:
 	CoreController* loadGame(const QString& path);
 	CoreController* loadGame(VFile* vf, const QString& path, const QString& base);