1/* Copyright (c) 2013-2016 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 "gb/io.h"
  9#include "gb/timer.h"
 10
 11mLOG_DEFINE_CATEGORY(GB_STATE, "GB Savestate");
 12
 13#ifdef _MSC_VER
 14#include <time.h>
 15#else
 16#include <sys/time.h>
 17#endif
 18
 19const uint32_t GB_SAVESTATE_MAGIC = 0x00400000;
 20const uint32_t GB_SAVESTATE_VERSION = 0x00000000;
 21
 22void GBSerialize(struct GB* gb, struct GBSerializedState* state) {
 23	STORE_32LE(GB_SAVESTATE_MAGIC + GB_SAVESTATE_VERSION, 0, &state->versionMagic);
 24	STORE_32LE(gb->romCrc32, 0, &state->romCrc32);
 25
 26	if (gb->memory.rom) {
 27		memcpy(state->title, ((struct GBCartridge*) gb->memory.rom)->titleLong, sizeof(state->title));
 28	} else {
 29		memset(state->title, 0, sizeof(state->title));
 30	}
 31
 32	state->model = gb->model;
 33
 34	state->cpu.a = gb->cpu->a;
 35	state->cpu.f = gb->cpu->f.packed;
 36	state->cpu.b = gb->cpu->b;
 37	state->cpu.c = gb->cpu->c;
 38	state->cpu.d = gb->cpu->d;
 39	state->cpu.e = gb->cpu->e;
 40	state->cpu.h = gb->cpu->h;
 41	state->cpu.l = gb->cpu->l;
 42	STORE_16LE(gb->cpu->sp, 0, &state->cpu.sp);
 43	STORE_16LE(gb->cpu->pc, 0, &state->cpu.pc);
 44
 45	STORE_32LE(gb->cpu->cycles, 0, &state->cpu.cycles);
 46	STORE_32LE(gb->cpu->nextEvent, 0, &state->cpu.nextEvent);
 47
 48	STORE_16LE(gb->cpu->index, 0, &state->cpu.index);
 49	state->cpu.bus = gb->cpu->bus;
 50	state->cpu.executionState = gb->cpu->executionState;
 51	STORE_16LE(gb->cpu->irqVector, 0, &state->cpu.irqVector);
 52
 53	GBSerializedCpuFlags flags = 0;
 54	flags = GBSerializedCpuFlagsSetCondition(flags, gb->cpu->condition);
 55	flags = GBSerializedCpuFlagsSetIrqPending(flags, gb->cpu->irqPending);
 56	flags = GBSerializedCpuFlagsSetDoubleSpeed(flags, gb->doubleSpeed);
 57	STORE_32LE(flags, 0, &state->cpu.flags);
 58
 59	GBMemorySerialize(gb, state);
 60	GBIOSerialize(gb, state);
 61	GBVideoSerialize(&gb->video, state);
 62	GBTimerSerialize(&gb->timer, state);
 63	GBAudioSerialize(&gb->audio, state);
 64
 65#ifndef _MSC_VER
 66	struct timeval tv;
 67	if (!gettimeofday(&tv, 0)) {
 68		uint64_t usec = tv.tv_usec;
 69		usec += tv.tv_sec * 1000000LL;
 70		STORE_64LE(usec, 0, &state->creationUsec);
 71	}
 72#else
 73	struct timespec ts;
 74	if (timespec_get(&ts, TIME_UTC)) {
 75		uint64_t usec = ts.tv_nsec / 1000;
 76		usec += ts.tv_sec * 1000000LL;
 77		STORE_64LE(usec, 0, &state->creationUsec);
 78	}
 79#endif
 80	else {
 81		state->creationUsec = 0;
 82	}
 83}
 84
 85bool GBDeserialize(struct GB* gb, const struct GBSerializedState* state) {
 86	bool error = false;
 87	int32_t check;
 88	uint32_t ucheck;
 89	int16_t check16;
 90	uint16_t ucheck16;
 91	LOAD_32LE(ucheck, 0, &state->versionMagic);
 92	if (ucheck > GB_SAVESTATE_MAGIC + GB_SAVESTATE_VERSION) {
 93		mLOG(GB_STATE, WARN, "Invalid or too new savestate: expected %08X, got %08X", GB_SAVESTATE_MAGIC + GB_SAVESTATE_VERSION, ucheck);
 94		error = true;
 95	} else if (ucheck < GB_SAVESTATE_MAGIC) {
 96		mLOG(GB_STATE, WARN, "Invalid savestate: expected %08X, got %08X", GB_SAVESTATE_MAGIC + GB_SAVESTATE_VERSION, ucheck);
 97		error = true;
 98	} else if (ucheck < GB_SAVESTATE_MAGIC + GB_SAVESTATE_VERSION) {
 99		mLOG(GB_STATE, WARN, "Old savestate: expected %08X, got %08X, continuing anyway", GB_SAVESTATE_MAGIC + GB_SAVESTATE_VERSION, ucheck);
100	}
101
102	if (gb->memory.rom && memcmp(state->title, ((struct GBCartridge*) gb->memory.rom)->titleLong, sizeof(state->title))) {
103		mLOG(GB_STATE, WARN, "Savestate is for a different game");
104		error = true;
105	}
106	LOAD_32LE(ucheck, 0, &state->romCrc32);
107	if (ucheck != gb->romCrc32) {
108		mLOG(GB_STATE, WARN, "Savestate is for a different version of the game");
109	}
110	LOAD_32LE(check, 0, &state->cpu.cycles);
111	if (check < 0) {
112		mLOG(GB_STATE, WARN, "Savestate is corrupted: CPU cycles are negative");
113		error = true;
114	}
115	if (state->cpu.executionState != LR35902_CORE_FETCH) {
116		mLOG(GB_STATE, WARN, "Savestate is corrupted: Execution state is not FETCH");
117		error = true;
118	}
119	if (check >= (int32_t) DMG_LR35902_FREQUENCY) {
120		mLOG(GB_STATE, WARN, "Savestate is corrupted: CPU cycles are too high");
121		error = true;
122	}
123	LOAD_32LE(check, 0, &state->video.eventDiff);
124	if (check < 0) {
125		mLOG(GB_STATE, WARN, "Savestate is corrupted: video eventDiff is negative");
126		error = true;
127	}
128	LOAD_16LE(check16, 0, &state->video.x);
129	if (check16 < 0 || check16 > GB_VIDEO_HORIZONTAL_PIXELS) {
130		mLOG(GB_STATE, WARN, "Savestate is corrupted: video x is out of range");
131		error = true;
132	}
133	LOAD_16LE(check16, 0, &state->video.ly);
134	if (check16 < 0 || check16 > GB_VIDEO_VERTICAL_TOTAL_PIXELS) {
135		mLOG(GB_STATE, WARN, "Savestate is corrupted: video y is out of range");
136		error = true;
137	}
138	LOAD_16LE(ucheck16, 0, &state->memory.dmaDest);
139	if (ucheck16 + state->memory.dmaRemaining > GB_SIZE_OAM) {
140		mLOG(GB_STATE, WARN, "Savestate is corrupted: DMA destination is out of range");
141		error = true;
142	}
143	LOAD_16LE(ucheck16, 0, &state->video.bcpIndex);
144	if (ucheck16 >= 0x40) {
145		mLOG(GB_STATE, WARN, "Savestate is corrupted: BCPS is out of range");
146	}
147	LOAD_16LE(ucheck16, 0, &state->video.ocpIndex);
148	if (ucheck16 >= 0x40) {
149		mLOG(GB_STATE, WARN, "Savestate is corrupted: OCPS is out of range");
150	}
151	if (error) {
152		return false;
153	}
154
155	gb->cpu->a = state->cpu.a;
156	gb->cpu->f.packed = state->cpu.f;
157	gb->cpu->b = state->cpu.b;
158	gb->cpu->c = state->cpu.c;
159	gb->cpu->d = state->cpu.d;
160	gb->cpu->e = state->cpu.e;
161	gb->cpu->h = state->cpu.h;
162	gb->cpu->l = state->cpu.l;
163	LOAD_16LE(gb->cpu->sp, 0, &state->cpu.sp);
164	LOAD_16LE(gb->cpu->pc, 0, &state->cpu.pc);
165
166	LOAD_16LE(gb->cpu->index, 0, &state->cpu.index);
167	gb->cpu->bus = state->cpu.bus;
168	gb->cpu->executionState = state->cpu.executionState;
169	LOAD_16LE(gb->cpu->irqVector, 0, &state->cpu.irqVector);
170
171	GBSerializedCpuFlags flags;
172	LOAD_32LE(flags, 0, &state->cpu.flags);
173	gb->cpu->condition = GBSerializedCpuFlagsGetCondition(flags);
174	gb->cpu->irqPending = GBSerializedCpuFlagsGetIrqPending(flags);
175	gb->doubleSpeed = GBSerializedCpuFlagsGetDoubleSpeed(flags);
176	gb->audio.timingFactor = gb->doubleSpeed + 1;
177
178	LOAD_32LE(gb->cpu->cycles, 0, &state->cpu.cycles);
179	LOAD_32LE(gb->cpu->nextEvent, 0, &state->cpu.nextEvent);
180
181	gb->model = state->model;
182
183	if (gb->model < GB_MODEL_CGB) {
184		gb->audio.style = GB_AUDIO_DMG;
185	} else {
186		gb->audio.style = GB_AUDIO_CGB;
187	}
188
189	GBMemoryDeserialize(gb, state);
190	GBIODeserialize(gb, state);
191	GBVideoDeserialize(&gb->video, state);
192	GBTimerDeserialize(&gb->timer, state);
193	GBAudioDeserialize(&gb->audio, state);
194
195	gb->cpu->memory.setActiveRegion(gb->cpu, gb->cpu->pc);
196
197	return true;
198}