all repos — mgba @ 2f2e5398719f9d6a78ae84fc241945b46839b01c

mGBA Game Boy Advance Emulator

src/gba/serialize.c (view raw)

  1/* Copyright (c) 2013-2015 Jeffrey Pfau
  2 *
  3 * This Source Code Form is subject to the terms of the Mozilla Public
  4 * License, v. 2.0. If a copy of the MPL was not distributed with this
  5 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
  6#include "serialize.h"
  7
  8#include "gba/audio.h"
  9#include "gba/io.h"
 10#include "gba/supervisor/rr.h"
 11#include "gba/supervisor/thread.h"
 12#include "gba/video.h"
 13
 14#include "util/memory.h"
 15#include "util/vfs.h"
 16
 17#include <fcntl.h>
 18
 19#ifdef USE_PNG
 20#include "util/png-io.h"
 21#include <png.h>
 22#include <zlib.h>
 23#endif
 24
 25const uint32_t GBA_SAVESTATE_MAGIC = 0x01000000;
 26
 27void GBASerialize(struct GBA* gba, struct GBASerializedState* state) {
 28	state->versionMagic = GBA_SAVESTATE_MAGIC;
 29	state->biosChecksum = gba->biosChecksum;
 30	state->romCrc32 = gba->romCrc32;
 31
 32	if (gba->memory.rom) {
 33		state->id = ((struct GBACartridge*) gba->memory.rom)->id;
 34		memcpy(state->title, ((struct GBACartridge*) gba->memory.rom)->title, sizeof(state->title));
 35	} else {
 36		state->id = 0;
 37		memset(state->title, 0, sizeof(state->title));
 38	}
 39
 40	memcpy(state->cpu.gprs, gba->cpu->gprs, sizeof(state->cpu.gprs));
 41	state->cpu.cpsr = gba->cpu->cpsr;
 42	state->cpu.spsr = gba->cpu->spsr;
 43	state->cpu.cycles = gba->cpu->cycles;
 44	state->cpu.nextEvent = gba->cpu->nextEvent;
 45	memcpy(state->cpu.bankedRegisters, gba->cpu->bankedRegisters, 6 * 7 * sizeof(int32_t));
 46	memcpy(state->cpu.bankedSPSRs, gba->cpu->bankedSPSRs, 6 * sizeof(int32_t));
 47
 48	state->biosPrefetch = gba->memory.biosPrefetch;
 49	state->cpuPrefetch[0] = gba->cpu->prefetch[0];
 50	state->cpuPrefetch[1] = gba->cpu->prefetch[1];
 51
 52	GBAMemorySerialize(&gba->memory, state);
 53	GBAIOSerialize(gba, state);
 54	GBAVideoSerialize(&gba->video, state);
 55	GBAAudioSerialize(&gba->audio, state);
 56	GBASavedataSerialize(&gba->memory.savedata, state, false);
 57
 58	state->associatedStreamId = 0;
 59	if (gba->rr) {
 60		gba->rr->stateSaved(gba->rr, state);
 61	}
 62}
 63
 64bool GBADeserialize(struct GBA* gba, const struct GBASerializedState* state) {
 65	bool error = false;
 66	if (state->versionMagic != GBA_SAVESTATE_MAGIC) {
 67		GBALog(gba, GBA_LOG_WARN, "Invalid or too new savestate");
 68		error = true;
 69	}
 70	if (state->biosChecksum != gba->biosChecksum) {
 71		GBALog(gba, GBA_LOG_WARN, "Savestate created using a different version of the BIOS");
 72		if (state->cpu.gprs[ARM_PC] < SIZE_BIOS && state->cpu.gprs[ARM_PC] >= 0x20) {
 73			error = true;
 74		}
 75	}
 76	if (gba->memory.rom && (state->id != ((struct GBACartridge*) gba->memory.rom)->id || memcmp(state->title, ((struct GBACartridge*) gba->memory.rom)->title, sizeof(state->title)))) {
 77		GBALog(gba, GBA_LOG_WARN, "Savestate is for a different game");
 78		error = true;
 79	} else if (!gba->memory.rom && state->id != 0) {
 80		GBALog(gba, GBA_LOG_WARN, "Savestate is for a game, but no game loaded");
 81		error = true;
 82	}
 83	if (state->romCrc32 != gba->romCrc32) {
 84		GBALog(gba, GBA_LOG_WARN, "Savestate is for a different version of the game");
 85	}
 86	if (state->cpu.cycles < 0) {
 87		GBALog(gba, GBA_LOG_WARN, "Savestate is corrupted: CPU cycles are negative");
 88		error = true;
 89	}
 90	if (state->video.eventDiff < 0) {
 91		GBALog(gba, GBA_LOG_WARN, "Savestate is corrupted: video eventDiff is negative");
 92		error = true;
 93	}
 94	if (state->video.nextHblank - state->video.eventDiff < 0) {
 95		GBALog(gba, GBA_LOG_WARN, "Savestate is corrupted: nextHblank is negative");
 96		error = true;
 97	}
 98	if (state->timers[0].overflowInterval < 0 || state->timers[1].overflowInterval < 0 || state->timers[2].overflowInterval < 0 || state->timers[3].overflowInterval < 0) {
 99		GBALog(gba, GBA_LOG_WARN, "Savestate is corrupted: overflowInterval is negative");
100		error = true;
101	}
102	if (state->audio.eventDiff < 0) {
103		GBALog(gba, GBA_LOG_WARN, "Savestate is corrupted: audio eventDiff is negative");
104		error = true;
105	}
106	if (state->audio.ch1.envelopeNextStep < 0 || state->audio.ch1.waveNextStep < 0 || state->audio.ch1.sweepNextStep < 0 || state->audio.ch1.nextEvent < 0) {
107		GBALog(gba, GBA_LOG_WARN, "Savestate is corrupted: audio channel 1 register is negative");
108		error = true;
109	}
110	if (state->audio.ch2.envelopeNextStep < 0 || state->audio.ch2.waveNextStep < 0 || state->audio.ch2.nextEvent < 0) {
111		GBALog(gba, GBA_LOG_WARN, "Savestate is corrupted: audio channel 2 register is negative");
112		error = true;
113	}
114	if (state->audio.ch3.nextEvent < 0) {
115		GBALog(gba, GBA_LOG_WARN, "Savestate is corrupted: audio channel 3 register is negative");
116		error = true;
117	}
118	if (state->audio.ch4.envelopeNextStep < 0 || state->audio.ch4.nextEvent < 0) {
119		GBALog(gba, GBA_LOG_WARN, "Savestate is corrupted: audio channel 4 register is negative");
120		error = true;
121	}
122	int region = (state->cpu.gprs[ARM_PC] >> BASE_OFFSET);
123	if ((region == REGION_CART0 || region == REGION_CART1 || region == REGION_CART2) && ((state->cpu.gprs[ARM_PC] - WORD_SIZE_ARM) & SIZE_CART0) >= gba->memory.romSize - WORD_SIZE_ARM) {
124		GBALog(gba, GBA_LOG_WARN, "Savestate created using a differently sized version of the ROM");
125		error = true;
126	}
127	if (error) {
128		return false;
129	}
130	memcpy(gba->cpu->gprs, state->cpu.gprs, sizeof(gba->cpu->gprs));
131	gba->cpu->cpsr = state->cpu.cpsr;
132	gba->cpu->spsr = state->cpu.spsr;
133	gba->cpu->cycles = state->cpu.cycles;
134	gba->cpu->nextEvent = state->cpu.nextEvent;
135	memcpy(gba->cpu->bankedRegisters, state->cpu.bankedRegisters, 6 * 7 * sizeof(int32_t));
136	memcpy(gba->cpu->bankedSPSRs, state->cpu.bankedSPSRs, 6 * sizeof(int32_t));
137	gba->cpu->privilegeMode = gba->cpu->cpsr.priv;
138	gba->cpu->memory.setActiveRegion(gba->cpu, gba->cpu->gprs[ARM_PC]);
139	if (state->biosPrefetch) {
140		gba->memory.biosPrefetch = state->biosPrefetch;
141	}
142	if (gba->cpu->cpsr.t) {
143		gba->cpu->executionMode = MODE_THUMB;
144		if (state->cpuPrefetch[0] && state->cpuPrefetch[1]) {
145			gba->cpu->prefetch[0] = state->cpuPrefetch[0] & 0xFFFF;
146			gba->cpu->prefetch[1] = state->cpuPrefetch[1] & 0xFFFF;
147		} else {
148			// Maintain backwards compat
149			LOAD_16(gba->cpu->prefetch[0], (gba->cpu->gprs[ARM_PC] - WORD_SIZE_THUMB) & gba->cpu->memory.activeMask, gba->cpu->memory.activeRegion);
150			LOAD_16(gba->cpu->prefetch[1], (gba->cpu->gprs[ARM_PC]) & gba->cpu->memory.activeMask, gba->cpu->memory.activeRegion);
151		}
152	} else {
153		gba->cpu->executionMode = MODE_ARM;
154		if (state->cpuPrefetch[0] && state->cpuPrefetch[1]) {
155			gba->cpu->prefetch[0] = state->cpuPrefetch[0];
156			gba->cpu->prefetch[1] = state->cpuPrefetch[1];
157		} else {
158			// Maintain backwards compat
159			LOAD_32(gba->cpu->prefetch[0], (gba->cpu->gprs[ARM_PC] - WORD_SIZE_ARM) & gba->cpu->memory.activeMask, gba->cpu->memory.activeRegion);
160			LOAD_32(gba->cpu->prefetch[1], (gba->cpu->gprs[ARM_PC]) & gba->cpu->memory.activeMask, gba->cpu->memory.activeRegion);
161		}
162	}
163
164	GBAMemoryDeserialize(&gba->memory, state);
165	GBAIODeserialize(gba, state);
166	GBAVideoDeserialize(&gba->video, state);
167	GBAAudioDeserialize(&gba->audio, state);
168	GBASavedataDeserialize(&gba->memory.savedata, state, false);
169
170	if (gba->rr) {
171		gba->rr->stateLoaded(gba->rr, state);
172	}
173	return true;
174}
175
176struct VFile* GBAGetState(struct GBA* gba, struct VDir* dir, int slot, bool write) {
177	char suffix[5] = { '\0' };
178	snprintf(suffix, sizeof(suffix), ".ss%d", slot);
179	return VDirOptionalOpenFile(dir, gba->activeFile, "savestate", suffix, write ? (O_CREAT | O_TRUNC | O_RDWR) : O_RDONLY);
180}
181
182#ifdef USE_PNG
183static bool _savePNGState(struct GBA* gba, struct VFile* vf) {
184	unsigned stride;
185	void* pixels = 0;
186	gba->video.renderer->getPixels(gba->video.renderer, &stride, &pixels);
187	if (!pixels) {
188		return false;
189	}
190
191	struct GBASerializedState* state = GBAAllocateState();
192	if (!state) {
193		return false;
194	}
195	png_structp png = PNGWriteOpen(vf);
196	png_infop info = PNGWriteHeader(png, VIDEO_HORIZONTAL_PIXELS, VIDEO_VERTICAL_PIXELS);
197	if (!png || !info) {
198		PNGWriteClose(png, info);
199		GBADeallocateState(state);
200		return false;
201	}
202	uLongf len = compressBound(sizeof(*state));
203	void* buffer = malloc(len);
204	if (!buffer) {
205		PNGWriteClose(png, info);
206		GBADeallocateState(state);
207		return false;
208	}
209	GBASerialize(gba, state);
210	compress(buffer, &len, (const Bytef*) state, sizeof(*state));
211	PNGWritePixels(png, VIDEO_HORIZONTAL_PIXELS, VIDEO_VERTICAL_PIXELS, stride, pixels);
212	PNGWriteCustomChunk(png, "gbAs", len, buffer);
213	PNGWriteClose(png, info);
214	free(buffer);
215	GBADeallocateState(state);
216	return true;
217}
218
219static int _loadPNGChunkHandler(png_structp png, png_unknown_chunkp chunk) {
220	if (strcmp((const char*) chunk->name, "gbAs") != 0) {
221		return 0;
222	}
223	struct GBASerializedState state;
224	uLongf len = sizeof(state);
225	uncompress((Bytef*) &state, &len, chunk->data, chunk->size);
226	return GBADeserialize(png_get_user_chunk_ptr(png), &state);
227}
228
229static bool _loadPNGState(struct GBA* gba, struct VFile* vf) {
230	png_structp png = PNGReadOpen(vf, PNG_HEADER_BYTES);
231	png_infop info = png_create_info_struct(png);
232	png_infop end = png_create_info_struct(png);
233	if (!png || !info || !end) {
234		PNGReadClose(png, info, end);
235		return false;
236	}
237	uint32_t* pixels = malloc(VIDEO_HORIZONTAL_PIXELS * VIDEO_VERTICAL_PIXELS * 4);
238
239	PNGInstallChunkHandler(png, gba, _loadPNGChunkHandler, "gbAs");
240	PNGReadHeader(png, info);
241	PNGReadPixels(png, info, pixels, VIDEO_HORIZONTAL_PIXELS, VIDEO_VERTICAL_PIXELS, VIDEO_HORIZONTAL_PIXELS);
242	PNGReadFooter(png, end);
243	PNGReadClose(png, info, end);
244	gba->video.renderer->putPixels(gba->video.renderer, VIDEO_HORIZONTAL_PIXELS, pixels);
245	GBASyncForceFrame(gba->sync);
246
247	free(pixels);
248	return true;
249}
250#endif
251
252bool GBASaveState(struct GBAThread* threadContext, struct VDir* dir, int slot, bool screenshot) {
253	struct VFile* vf = GBAGetState(threadContext->gba, dir, slot, true);
254	if (!vf) {
255		return false;
256	}
257	bool success = GBASaveStateNamed(threadContext->gba, vf, screenshot);
258	vf->close(vf);
259	if (success) {
260		GBALog(threadContext->gba, GBA_LOG_STATUS, "State %i saved", slot);
261	} else {
262		GBALog(threadContext->gba, GBA_LOG_STATUS, "State %i failed to save", slot);
263	}
264	return success;
265}
266
267bool GBALoadState(struct GBAThread* threadContext, struct VDir* dir, int slot) {
268	struct VFile* vf = GBAGetState(threadContext->gba, dir, slot, false);
269	if (!vf) {
270		return false;
271	}
272	threadContext->rewindBufferSize = 0;
273	bool success = GBALoadStateNamed(threadContext->gba, vf);
274	vf->close(vf);
275	if (success) {
276		GBALog(threadContext->gba, GBA_LOG_STATUS, "State %i loaded", slot);
277	} else {
278		GBALog(threadContext->gba, GBA_LOG_STATUS, "State %i failed to load", slot);
279	}
280	return success;
281}
282
283bool GBASaveStateNamed(struct GBA* gba, struct VFile* vf, bool screenshot) {
284	if (!screenshot) {
285		vf->truncate(vf, sizeof(struct GBASerializedState));
286		struct GBASerializedState* state = vf->map(vf, sizeof(struct GBASerializedState), MAP_WRITE);
287		if (!state) {
288			return false;
289		}
290		GBASerialize(gba, state);
291		vf->unmap(vf, state, sizeof(struct GBASerializedState));
292		return true;
293	}
294	#ifdef USE_PNG
295	else {
296		return _savePNGState(gba, vf);
297	}
298	#endif
299	return false;
300}
301
302bool GBALoadStateNamed(struct GBA* gba, struct VFile* vf) {
303	#ifdef USE_PNG
304	if (isPNG(vf)) {
305		return _loadPNGState(gba, vf);
306	}
307	#endif
308	if (vf->size(vf) < (ssize_t) sizeof(struct GBASerializedState)) {
309		return false;
310	}
311	struct GBASerializedState* state = vf->map(vf, sizeof(struct GBASerializedState), MAP_READ);
312	if (!state) {
313		return false;
314	}
315	bool success = GBADeserialize(gba, state);
316	vf->unmap(vf, state, sizeof(struct GBASerializedState));
317	return success;
318}
319
320struct GBASerializedState* GBAAllocateState(void) {
321	return anonymousMemoryMap(sizeof(struct GBASerializedState));
322}
323
324void GBADeallocateState(struct GBASerializedState* state) {
325	mappedMemoryFree(state, sizeof(struct GBASerializedState));
326}
327
328void GBARecordFrame(struct GBAThread* thread) {
329	int offset = thread->rewindBufferWriteOffset;
330	struct GBASerializedState* state = thread->rewindBuffer[offset];
331	if (!state) {
332		state = GBAAllocateState();
333		thread->rewindBuffer[offset] = state;
334	}
335	GBASerialize(thread->gba, state);
336
337	if (thread->rewindScreenBuffer) {
338		unsigned stride;
339		uint8_t* pixels = 0;
340		thread->gba->video.renderer->getPixels(thread->gba->video.renderer, &stride, (void*) &pixels);
341		if (pixels) {
342			size_t y;
343			for (y = 0; y < VIDEO_VERTICAL_PIXELS; ++y) {
344				memcpy(&thread->rewindScreenBuffer[(offset * VIDEO_VERTICAL_PIXELS + y) * VIDEO_HORIZONTAL_PIXELS * BYTES_PER_PIXEL], &pixels[y * stride * BYTES_PER_PIXEL], VIDEO_HORIZONTAL_PIXELS * BYTES_PER_PIXEL);
345			}
346		}
347	}
348	thread->rewindBufferSize = thread->rewindBufferSize == thread->rewindBufferCapacity ? thread->rewindBufferCapacity : thread->rewindBufferSize + 1;
349	thread->rewindBufferWriteOffset = (offset + 1) % thread->rewindBufferCapacity;
350}
351
352void GBARewindSettingsChanged(struct GBAThread* threadContext, int newCapacity, int newInterval) {
353	if (newCapacity == threadContext->rewindBufferCapacity && newInterval == threadContext->rewindBufferInterval) {
354		return;
355	}
356	threadContext->rewindBufferInterval = newInterval;
357	threadContext->rewindBufferNext = threadContext->rewindBufferInterval;
358	threadContext->rewindBufferSize = 0;
359	if (threadContext->rewindBuffer) {
360		int i;
361		for (i = 0; i < threadContext->rewindBufferCapacity; ++i) {
362			GBADeallocateState(threadContext->rewindBuffer[i]);
363		}
364		free(threadContext->rewindBuffer);
365		free(threadContext->rewindScreenBuffer);
366	}
367	threadContext->rewindBufferCapacity = newCapacity;
368	if (threadContext->rewindBufferCapacity > 0) {
369		threadContext->rewindBuffer = calloc(threadContext->rewindBufferCapacity, sizeof(struct GBASerializedState*));
370		threadContext->rewindScreenBuffer = calloc(threadContext->rewindBufferCapacity, VIDEO_VERTICAL_PIXELS * VIDEO_HORIZONTAL_PIXELS * BYTES_PER_PIXEL);
371	} else {
372		threadContext->rewindBuffer = 0;
373		threadContext->rewindScreenBuffer = 0;
374	}
375}
376
377int GBARewind(struct GBAThread* thread, int nStates) {
378	if (nStates > thread->rewindBufferSize || nStates < 0) {
379		nStates = thread->rewindBufferSize;
380	}
381	if (nStates == 0) {
382		return 0;
383	}
384	int offset = thread->rewindBufferWriteOffset - nStates;
385	if (offset < 0) {
386		offset += thread->rewindBufferCapacity;
387	}
388	struct GBASerializedState* state = thread->rewindBuffer[offset];
389	if (!state) {
390		return 0;
391	}
392	thread->rewindBufferSize -= nStates;
393	thread->rewindBufferWriteOffset = offset;
394	GBADeserialize(thread->gba, state);
395	if (thread->rewindScreenBuffer) {
396		thread->gba->video.renderer->putPixels(thread->gba->video.renderer, VIDEO_HORIZONTAL_PIXELS, &thread->rewindScreenBuffer[offset * VIDEO_HORIZONTAL_PIXELS * VIDEO_VERTICAL_PIXELS * BYTES_PER_PIXEL]);
397	}
398	return nStates;
399}
400
401void GBARewindAll(struct GBAThread* thread) {
402	GBARewind(thread, thread->rewindBufferSize);
403}