all repos — mgba @ 6822b8cabe2bca29944fe88f18226f1b89eab055

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->cpu.nextEvent < 0) {
 91		GBALog(gba, GBA_LOG_WARN, "Savestate is corrupted: Next event is negative");
 92		error = true;
 93	}
 94	if (state->video.eventDiff < 0) {
 95		GBALog(gba, GBA_LOG_WARN, "Savestate is corrupted: video eventDiff is negative");
 96		error = true;
 97	}
 98	if (state->video.nextHblank - state->video.eventDiff < 0) {
 99		GBALog(gba, GBA_LOG_WARN, "Savestate is corrupted: nextHblank is negative");
100		error = true;
101	}
102	if (state->timers[0].overflowInterval < 0 || state->timers[1].overflowInterval < 0 || state->timers[2].overflowInterval < 0 || state->timers[3].overflowInterval < 0) {
103		GBALog(gba, GBA_LOG_WARN, "Savestate is corrupted: overflowInterval is negative");
104		error = true;
105	}
106	if (state->audio.eventDiff < 0) {
107		GBALog(gba, GBA_LOG_WARN, "Savestate is corrupted: audio eventDiff is negative");
108		error = true;
109	}
110	if (!state->audio.ch1Dead && (state->audio.ch1.envelopeNextStep < 0 ||
111		                          state->audio.ch1.waveNextStep < 0 ||
112		                          state->audio.ch1.sweepNextStep < 0 ||
113		                          state->audio.ch1.nextEvent < 0)) {
114		GBALog(gba, GBA_LOG_WARN, "Savestate is corrupted: audio channel 1 register is negative");
115		error = true;
116	}
117	if (!state->audio.ch2Dead && (state->audio.ch2.envelopeNextStep < 0 ||
118		                          state->audio.ch2.waveNextStep < 0 ||
119		                          state->audio.ch2.nextEvent < 0)) {
120		GBALog(gba, GBA_LOG_WARN, "Savestate is corrupted: audio channel 2 register is negative");
121		error = true;
122	}
123	if (state->audio.ch3.nextEvent < 0) {
124		GBALog(gba, GBA_LOG_WARN, "Savestate is corrupted: audio channel 3 register is negative");
125		error = true;
126	}
127	if (!state->audio.ch4Dead && (state->audio.ch4.envelopeNextStep < 0 ||
128		                          state->audio.ch4.nextEvent < 0)) {
129		GBALog(gba, GBA_LOG_WARN, "Savestate is corrupted: audio channel 4 register is negative");
130		error = true;
131	}
132	int region = (state->cpu.gprs[ARM_PC] >> BASE_OFFSET);
133	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) {
134		GBALog(gba, GBA_LOG_WARN, "Savestate created using a differently sized version of the ROM");
135		error = true;
136	}
137	if (error) {
138		return false;
139	}
140	memcpy(gba->cpu->gprs, state->cpu.gprs, sizeof(gba->cpu->gprs));
141	gba->cpu->cpsr = state->cpu.cpsr;
142	gba->cpu->spsr = state->cpu.spsr;
143	gba->cpu->cycles = state->cpu.cycles;
144	gba->cpu->nextEvent = state->cpu.nextEvent;
145	memcpy(gba->cpu->bankedRegisters, state->cpu.bankedRegisters, 6 * 7 * sizeof(int32_t));
146	memcpy(gba->cpu->bankedSPSRs, state->cpu.bankedSPSRs, 6 * sizeof(int32_t));
147	gba->cpu->privilegeMode = gba->cpu->cpsr.priv;
148	gba->cpu->memory.setActiveRegion(gba->cpu, gba->cpu->gprs[ARM_PC]);
149	if (state->biosPrefetch) {
150		gba->memory.biosPrefetch = state->biosPrefetch;
151	}
152	if (gba->cpu->cpsr.t) {
153		gba->cpu->executionMode = MODE_THUMB;
154		if (state->cpuPrefetch[0] && state->cpuPrefetch[1]) {
155			gba->cpu->prefetch[0] = state->cpuPrefetch[0] & 0xFFFF;
156			gba->cpu->prefetch[1] = state->cpuPrefetch[1] & 0xFFFF;
157		} else {
158			// Maintain backwards compat
159			LOAD_16(gba->cpu->prefetch[0], (gba->cpu->gprs[ARM_PC] - WORD_SIZE_THUMB) & gba->cpu->memory.activeMask, gba->cpu->memory.activeRegion);
160			LOAD_16(gba->cpu->prefetch[1], (gba->cpu->gprs[ARM_PC]) & gba->cpu->memory.activeMask, gba->cpu->memory.activeRegion);
161		}
162	} else {
163		gba->cpu->executionMode = MODE_ARM;
164		if (state->cpuPrefetch[0] && state->cpuPrefetch[1]) {
165			gba->cpu->prefetch[0] = state->cpuPrefetch[0];
166			gba->cpu->prefetch[1] = state->cpuPrefetch[1];
167		} else {
168			// Maintain backwards compat
169			LOAD_32(gba->cpu->prefetch[0], (gba->cpu->gprs[ARM_PC] - WORD_SIZE_ARM) & gba->cpu->memory.activeMask, gba->cpu->memory.activeRegion);
170			LOAD_32(gba->cpu->prefetch[1], (gba->cpu->gprs[ARM_PC]) & gba->cpu->memory.activeMask, gba->cpu->memory.activeRegion);
171		}
172	}
173
174	GBAMemoryDeserialize(&gba->memory, state);
175	GBAIODeserialize(gba, state);
176	GBAVideoDeserialize(&gba->video, state);
177	GBAAudioDeserialize(&gba->audio, state);
178	GBASavedataDeserialize(&gba->memory.savedata, state, false);
179
180	if (gba->rr) {
181		gba->rr->stateLoaded(gba->rr, state);
182	}
183	return true;
184}
185
186struct VFile* GBAGetState(struct GBA* gba, struct VDir* dir, int slot, bool write) {
187	char suffix[5] = { '\0' };
188	snprintf(suffix, sizeof(suffix), ".ss%d", slot);
189	return VDirOptionalOpenFile(dir, gba->activeFile, "savestate", suffix, write ? (O_CREAT | O_TRUNC | O_RDWR) : O_RDONLY);
190}
191
192#ifdef USE_PNG
193static bool _savePNGState(struct GBA* gba, struct VFile* vf) {
194	unsigned stride;
195	void* pixels = 0;
196	gba->video.renderer->getPixels(gba->video.renderer, &stride, &pixels);
197	if (!pixels) {
198		return false;
199	}
200
201	struct GBASerializedState* state = GBAAllocateState();
202	if (!state) {
203		return false;
204	}
205	png_structp png = PNGWriteOpen(vf);
206	png_infop info = PNGWriteHeader(png, VIDEO_HORIZONTAL_PIXELS, VIDEO_VERTICAL_PIXELS);
207	if (!png || !info) {
208		PNGWriteClose(png, info);
209		GBADeallocateState(state);
210		return false;
211	}
212	uLongf len = compressBound(sizeof(*state));
213	void* buffer = malloc(len);
214	if (!buffer) {
215		PNGWriteClose(png, info);
216		GBADeallocateState(state);
217		return false;
218	}
219	GBASerialize(gba, state);
220	compress(buffer, &len, (const Bytef*) state, sizeof(*state));
221	PNGWritePixels(png, VIDEO_HORIZONTAL_PIXELS, VIDEO_VERTICAL_PIXELS, stride, pixels);
222	PNGWriteCustomChunk(png, "gbAs", len, buffer);
223	PNGWriteClose(png, info);
224	free(buffer);
225	GBADeallocateState(state);
226	return true;
227}
228
229static int _loadPNGChunkHandler(png_structp png, png_unknown_chunkp chunk) {
230	if (strcmp((const char*) chunk->name, "gbAs") != 0) {
231		return 0;
232	}
233	struct GBASerializedState state;
234	uLongf len = sizeof(state);
235	uncompress((Bytef*) &state, &len, chunk->data, chunk->size);
236	if (!GBADeserialize(png_get_user_chunk_ptr(png), &state)) {
237		longjmp(png_jmpbuf(png), 1);
238	}
239	return 1;
240}
241
242static bool _loadPNGState(struct GBA* gba, struct VFile* vf) {
243	png_structp png = PNGReadOpen(vf, PNG_HEADER_BYTES);
244	png_infop info = png_create_info_struct(png);
245	png_infop end = png_create_info_struct(png);
246	if (!png || !info || !end) {
247		PNGReadClose(png, info, end);
248		return false;
249	}
250	uint32_t* pixels = malloc(VIDEO_HORIZONTAL_PIXELS * VIDEO_VERTICAL_PIXELS * 4);
251
252	PNGInstallChunkHandler(png, gba, _loadPNGChunkHandler, "gbAs");
253	bool success = PNGReadHeader(png, info);
254	success = success && PNGReadPixels(png, info, pixels, VIDEO_HORIZONTAL_PIXELS, VIDEO_VERTICAL_PIXELS, VIDEO_HORIZONTAL_PIXELS);
255	success = success && PNGReadFooter(png, end);
256	PNGReadClose(png, info, end);
257	if (success) {
258		gba->video.renderer->putPixels(gba->video.renderer, VIDEO_HORIZONTAL_PIXELS, pixels);
259		GBASyncForceFrame(gba->sync);
260	}
261
262	free(pixels);
263	return success;
264}
265#endif
266
267bool GBASaveState(struct GBAThread* threadContext, struct VDir* dir, int slot, bool screenshot) {
268	struct VFile* vf = GBAGetState(threadContext->gba, dir, slot, true);
269	if (!vf) {
270		return false;
271	}
272	bool success = GBASaveStateNamed(threadContext->gba, vf, screenshot);
273	vf->close(vf);
274	if (success) {
275		GBALog(threadContext->gba, GBA_LOG_STATUS, "State %i saved", slot);
276	} else {
277		GBALog(threadContext->gba, GBA_LOG_STATUS, "State %i failed to save", slot);
278	}
279	return success;
280}
281
282bool GBALoadState(struct GBAThread* threadContext, struct VDir* dir, int slot) {
283	struct VFile* vf = GBAGetState(threadContext->gba, dir, slot, false);
284	if (!vf) {
285		return false;
286	}
287	threadContext->rewindBufferSize = 0;
288	bool success = GBALoadStateNamed(threadContext->gba, vf);
289	vf->close(vf);
290	if (success) {
291		GBALog(threadContext->gba, GBA_LOG_STATUS, "State %i loaded", slot);
292	} else {
293		GBALog(threadContext->gba, GBA_LOG_STATUS, "State %i failed to load", slot);
294	}
295	return success;
296}
297
298bool GBASaveStateNamed(struct GBA* gba, struct VFile* vf, bool screenshot) {
299	if (!screenshot) {
300		vf->truncate(vf, sizeof(struct GBASerializedState));
301		struct GBASerializedState* state = vf->map(vf, sizeof(struct GBASerializedState), MAP_WRITE);
302		if (!state) {
303			return false;
304		}
305		GBASerialize(gba, state);
306		vf->unmap(vf, state, sizeof(struct GBASerializedState));
307		return true;
308	}
309#ifdef USE_PNG
310	else {
311		return _savePNGState(gba, vf);
312	}
313#endif
314	return false;
315}
316
317bool GBALoadStateNamed(struct GBA* gba, struct VFile* vf) {
318#ifdef USE_PNG
319	if (isPNG(vf)) {
320		return _loadPNGState(gba, vf);
321	}
322#endif
323	if (vf->size(vf) < (ssize_t) sizeof(struct GBASerializedState)) {
324		return false;
325	}
326	struct GBASerializedState* state = vf->map(vf, sizeof(struct GBASerializedState), MAP_READ);
327	if (!state) {
328		return false;
329	}
330	bool success = GBADeserialize(gba, state);
331	vf->unmap(vf, state, sizeof(struct GBASerializedState));
332	return success;
333}
334
335struct GBASerializedState* GBAAllocateState(void) {
336	return anonymousMemoryMap(sizeof(struct GBASerializedState));
337}
338
339void GBADeallocateState(struct GBASerializedState* state) {
340	mappedMemoryFree(state, sizeof(struct GBASerializedState));
341}
342
343void GBARecordFrame(struct GBAThread* thread) {
344	int offset = thread->rewindBufferWriteOffset;
345	struct GBASerializedState* state = thread->rewindBuffer[offset];
346	if (!state) {
347		state = GBAAllocateState();
348		thread->rewindBuffer[offset] = state;
349	}
350	GBASerialize(thread->gba, state);
351
352	if (thread->rewindScreenBuffer) {
353		unsigned stride;
354		uint8_t* pixels = 0;
355		thread->gba->video.renderer->getPixels(thread->gba->video.renderer, &stride, (void*) &pixels);
356		if (pixels) {
357			size_t y;
358			for (y = 0; y < VIDEO_VERTICAL_PIXELS; ++y) {
359				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);
360			}
361		}
362	}
363	thread->rewindBufferSize = thread->rewindBufferSize == thread->rewindBufferCapacity ? thread->rewindBufferCapacity : thread->rewindBufferSize + 1;
364	thread->rewindBufferWriteOffset = (offset + 1) % thread->rewindBufferCapacity;
365}
366
367void GBARewindSettingsChanged(struct GBAThread* threadContext, int newCapacity, int newInterval) {
368	if (newCapacity == threadContext->rewindBufferCapacity && newInterval == threadContext->rewindBufferInterval) {
369		return;
370	}
371	threadContext->rewindBufferInterval = newInterval;
372	threadContext->rewindBufferNext = threadContext->rewindBufferInterval;
373	threadContext->rewindBufferSize = 0;
374	if (threadContext->rewindBuffer) {
375		int i;
376		for (i = 0; i < threadContext->rewindBufferCapacity; ++i) {
377			GBADeallocateState(threadContext->rewindBuffer[i]);
378		}
379		free(threadContext->rewindBuffer);
380		free(threadContext->rewindScreenBuffer);
381	}
382	threadContext->rewindBufferCapacity = newCapacity;
383	if (threadContext->rewindBufferCapacity > 0) {
384		threadContext->rewindBuffer = calloc(threadContext->rewindBufferCapacity, sizeof(struct GBASerializedState*));
385		threadContext->rewindScreenBuffer = calloc(threadContext->rewindBufferCapacity, VIDEO_VERTICAL_PIXELS * VIDEO_HORIZONTAL_PIXELS * BYTES_PER_PIXEL);
386	} else {
387		threadContext->rewindBuffer = 0;
388		threadContext->rewindScreenBuffer = 0;
389	}
390}
391
392int GBARewind(struct GBAThread* thread, int nStates) {
393	if (nStates > thread->rewindBufferSize || nStates < 0) {
394		nStates = thread->rewindBufferSize;
395	}
396	if (nStates == 0) {
397		return 0;
398	}
399	int offset = thread->rewindBufferWriteOffset - nStates;
400	if (offset < 0) {
401		offset += thread->rewindBufferCapacity;
402	}
403	struct GBASerializedState* state = thread->rewindBuffer[offset];
404	if (!state) {
405		return 0;
406	}
407	thread->rewindBufferSize -= nStates;
408	thread->rewindBufferWriteOffset = offset;
409	GBADeserialize(thread->gba, state);
410	if (thread->rewindScreenBuffer) {
411		thread->gba->video.renderer->putPixels(thread->gba->video.renderer, VIDEO_HORIZONTAL_PIXELS, &thread->rewindScreenBuffer[offset * VIDEO_HORIZONTAL_PIXELS * VIDEO_VERTICAL_PIXELS * BYTES_PER_PIXEL]);
412	}
413	return nStates;
414}
415
416void GBARewindAll(struct GBAThread* thread) {
417	GBARewind(thread, thread->rewindBufferSize);
418}