src/gba/gba-serialize.c (view raw)
1#include "gba-serialize.h"
2
3#include "gba-audio.h"
4#include "gba-io.h"
5#include "gba-rr.h"
6#include "gba-thread.h"
7#include "gba-video.h"
8
9#include "util/memory.h"
10#include "util/png-io.h"
11#include "util/vfs.h"
12
13#include <fcntl.h>
14#include <png.h>
15#include <zlib.h>
16
17const uint32_t GBA_SAVESTATE_MAGIC = 0x01000000;
18
19void GBASerialize(struct GBA* gba, struct GBASerializedState* state) {
20 state->versionMagic = GBA_SAVESTATE_MAGIC;
21 state->biosChecksum = gba->biosChecksum;
22 state->romCrc32 = gba->romCrc32;
23
24 state->id = ((struct GBACartridge*) gba->memory.rom)->id;
25 memcpy(state->title, ((struct GBACartridge*) gba->memory.rom)->title, sizeof(state->title));
26
27 memcpy(state->cpu.gprs, gba->cpu->gprs, sizeof(state->cpu.gprs));
28 state->cpu.cpsr = gba->cpu->cpsr;
29 state->cpu.spsr = gba->cpu->spsr;
30 state->cpu.cycles = gba->cpu->cycles;
31 state->cpu.nextEvent = gba->cpu->nextEvent;
32 memcpy(state->cpu.bankedRegisters, gba->cpu->bankedRegisters, 6 * 7 * sizeof(int32_t));
33 memcpy(state->cpu.bankedSPSRs, gba->cpu->bankedSPSRs, 6 * sizeof(int32_t));
34
35 GBAMemorySerialize(&gba->memory, state);
36 GBAIOSerialize(gba, state);
37 GBAVideoSerialize(&gba->video, state);
38 GBAAudioSerialize(&gba->audio, state);
39
40 if (GBARRIsRecording(gba->rr)) {
41 state->associatedStreamId = gba->rr->streamId;
42 GBARRFinishSegment(gba->rr);
43 } else {
44 state->associatedStreamId = 0;
45 }
46}
47
48void GBADeserialize(struct GBA* gba, struct GBASerializedState* state) {
49 if (state->versionMagic != GBA_SAVESTATE_MAGIC) {
50 GBALog(gba, GBA_LOG_WARN, "Invalid or too new savestate");
51 return;
52 }
53 if (state->biosChecksum != gba->biosChecksum) {
54 GBALog(gba, GBA_LOG_WARN, "Savestate created using a different version of the BIOS");
55 if (state->cpu.gprs[ARM_PC] < SIZE_BIOS && state->cpu.gprs[ARM_PC] >= 0x20) {
56 return;
57 }
58 }
59 if (state->id != ((struct GBACartridge*) gba->memory.rom)->id || memcmp(state->title, ((struct GBACartridge*) gba->memory.rom)->title, sizeof(state->title))) {
60 GBALog(gba, GBA_LOG_WARN, "Savestate is for a different game");
61 return;
62 }
63 if (state->romCrc32 != gba->romCrc32) {
64 GBALog(gba, GBA_LOG_WARN, "Savestate is for a different version of the game");
65 }
66 memcpy(gba->cpu->gprs, state->cpu.gprs, sizeof(gba->cpu->gprs));
67 gba->cpu->cpsr = state->cpu.cpsr;
68 gba->cpu->spsr = state->cpu.spsr;
69 gba->cpu->cycles = state->cpu.cycles;
70 gba->cpu->nextEvent = state->cpu.nextEvent;
71 memcpy(gba->cpu->bankedRegisters, state->cpu.bankedRegisters, 6 * 7 * sizeof(int32_t));
72 memcpy(gba->cpu->bankedSPSRs, state->cpu.bankedSPSRs, 6 * sizeof(int32_t));
73 gba->cpu->privilegeMode = gba->cpu->cpsr.priv;
74 gba->cpu->memory.setActiveRegion(gba->cpu, gba->cpu->gprs[ARM_PC]);
75 if (gba->cpu->cpsr.t) {
76 gba->cpu->executionMode = MODE_THUMB;
77 LOAD_16(gba->cpu->prefetch, (gba->cpu->gprs[ARM_PC] - WORD_SIZE_THUMB) & gba->cpu->memory.activeMask, gba->cpu->memory.activeRegion);
78 } else {
79 gba->cpu->executionMode = MODE_ARM;
80 LOAD_32(gba->cpu->prefetch, (gba->cpu->gprs[ARM_PC] - WORD_SIZE_ARM) & gba->cpu->memory.activeMask, gba->cpu->memory.activeRegion);
81 }
82
83 GBAMemoryDeserialize(&gba->memory, state);
84 GBAIODeserialize(gba, state);
85 GBAVideoDeserialize(&gba->video, state);
86 GBAAudioDeserialize(&gba->audio, state);
87
88 if (GBARRIsRecording(gba->rr)) {
89 if (state->associatedStreamId != gba->rr->streamId) {
90 GBARRLoadStream(gba->rr, state->associatedStreamId);
91 GBARRIncrementStream(gba->rr, true);
92 } else {
93 GBARRFinishSegment(gba->rr);
94 }
95 GBARRMarkRerecord(gba->rr);
96 } else if (GBARRIsPlaying(gba->rr)) {
97 GBARRLoadStream(gba->rr, state->associatedStreamId);
98 GBARRSkipSegment(gba->rr);
99 }
100}
101
102static struct VFile* _getStateVf(struct GBA* gba, struct VDir* dir, int slot, bool write) {
103 char path[PATH_MAX];
104 path[PATH_MAX - 1] = '\0';
105 struct VFile* vf;
106 if (!dir) {
107 snprintf(path, PATH_MAX - 1, "%s.ss%d", gba->activeFile, slot);
108 vf = VFileOpen(path, write ? (O_CREAT | O_TRUNC | O_RDWR) : O_RDONLY);
109 } else {
110 snprintf(path, PATH_MAX - 1, "savestate.ss%d", slot);
111 vf = dir->openFile(dir, path, write ? (O_CREAT | O_TRUNC | O_RDWR) : O_RDONLY);
112 }
113 return vf;
114}
115
116static bool _savePNGState(struct GBA* gba, struct VFile* vf) {
117 unsigned stride;
118 void* pixels = 0;
119 gba->video.renderer->getPixels(gba->video.renderer, &stride, &pixels);
120 if (!pixels) {
121 return false;
122 }
123
124 struct GBASerializedState* state = GBAAllocateState();
125 png_structp png = PNGWriteOpen(vf);
126 png_infop info = PNGWriteHeader(png, VIDEO_HORIZONTAL_PIXELS, VIDEO_VERTICAL_PIXELS);
127 uLongf len = compressBound(sizeof(*state));
128 void* buffer = malloc(len);
129 if (state && png && info && buffer) {
130 GBASerialize(gba, state);
131 compress(buffer, &len, (const Bytef*) state, sizeof(*state));
132 PNGWritePixels(png, VIDEO_HORIZONTAL_PIXELS, VIDEO_VERTICAL_PIXELS, stride, pixels);
133 PNGWriteCustomChunk(png, "gbAs", len, buffer);
134 }
135 PNGWriteClose(png, info);
136 free(buffer);
137 GBADeallocateState(state);
138 return state && png && info && buffer;
139}
140
141static int _loadPNGChunkHandler(png_structp png, png_unknown_chunkp chunk) {
142 if (strcmp((const char*) chunk->name, "gbAs") != 0) {
143 return 0;
144 }
145 struct GBASerializedState state;
146 uLongf len = sizeof(state);
147 uncompress((Bytef*) &state, &len, chunk->data, chunk->size);
148 GBADeserialize(png_get_user_chunk_ptr(png), &state);
149 return 1;
150}
151
152static bool _loadPNGState(struct GBA* gba, struct VFile* vf) {
153 png_structp png = PNGReadOpen(vf, PNG_HEADER_BYTES);
154 png_infop info = png_create_info_struct(png);
155 png_infop end = png_create_info_struct(png);
156 if (!png || !info || !end) {
157 PNGReadClose(png, info, end);
158 return false;
159 }
160 uint32_t pixels[VIDEO_HORIZONTAL_PIXELS * VIDEO_VERTICAL_PIXELS * 4];
161
162 PNGInstallChunkHandler(png, gba, _loadPNGChunkHandler, "gbAs");
163 PNGReadHeader(png, info);
164 PNGReadPixels(png, info, &pixels, VIDEO_HORIZONTAL_PIXELS, VIDEO_VERTICAL_PIXELS, VIDEO_HORIZONTAL_PIXELS);
165 PNGReadFooter(png, end);
166 PNGReadClose(png, info, end);
167 gba->video.renderer->putPixels(gba->video.renderer, VIDEO_HORIZONTAL_PIXELS, pixels);
168 GBASyncPostFrame(gba->sync);
169 return true;
170}
171
172bool GBASaveState(struct GBA* gba, struct VDir* dir, int slot, bool screenshot) {
173 struct VFile* vf = _getStateVf(gba, dir, slot, true);
174 if (!vf) {
175 return false;
176 }
177 bool success = GBASaveStateNamed(gba, vf, screenshot);
178 vf->close(vf);
179 return success;
180}
181
182bool GBALoadState(struct GBA* gba, struct VDir* dir, int slot) {
183 struct VFile* vf = _getStateVf(gba, dir, slot, false);
184 if (!vf) {
185 return false;
186 }
187 bool success = GBALoadStateNamed(gba, vf);
188 vf->close(vf);
189 return success;
190}
191
192bool GBASaveStateNamed(struct GBA* gba, struct VFile* vf, bool screenshot) {
193 if (!screenshot) {
194 vf->truncate(vf, sizeof(struct GBASerializedState));
195 struct GBASerializedState* state = vf->map(vf, sizeof(struct GBASerializedState), MAP_WRITE);
196 if (!state) {
197 return false;
198 }
199 GBASerialize(gba, state);
200 vf->unmap(vf, state, sizeof(struct GBASerializedState));
201 } else {
202 return _savePNGState(gba, vf);
203 }
204 return true;
205}
206
207bool GBALoadStateNamed(struct GBA* gba, struct VFile* vf) {
208 if (!isPNG(vf)) {
209 struct GBASerializedState* state = vf->map(vf, sizeof(struct GBASerializedState), MAP_READ);
210 if (!state) {
211 return false;
212 }
213 GBADeserialize(gba, state);
214 vf->unmap(vf, state, sizeof(struct GBASerializedState));
215 } else {
216 return _loadPNGState(gba, vf);
217 }
218 return true;
219}
220
221struct GBASerializedState* GBAAllocateState(void) {
222 return anonymousMemoryMap(sizeof(struct GBASerializedState));
223}
224
225void GBADeallocateState(struct GBASerializedState* state) {
226 mappedMemoryFree(state, sizeof(struct GBASerializedState));
227}
228
229void GBARecordFrame(struct GBAThread* thread) {
230 int offset = thread->rewindBufferWriteOffset;
231 struct GBASerializedState* state = thread->rewindBuffer[offset];
232 if (!state) {
233 state = GBAAllocateState();
234 thread->rewindBuffer[offset] = state;
235 }
236 GBASerialize(thread->gba, state);
237 thread->rewindBufferSize = thread->rewindBufferSize == thread->rewindBufferCapacity ? thread->rewindBufferCapacity : thread->rewindBufferSize + 1;
238 thread->rewindBufferWriteOffset = (offset + 1) % thread->rewindBufferCapacity;
239}
240
241void GBARewind(struct GBAThread* thread, int nStates) {
242 if (nStates > thread->rewindBufferSize || nStates < 0) {
243 nStates = thread->rewindBufferSize;
244 }
245 if (nStates == 0) {
246 return;
247 }
248 int offset = thread->rewindBufferWriteOffset - nStates;
249 if (offset < 0) {
250 offset += thread->rewindBufferSize;
251 }
252 struct GBASerializedState* state = thread->rewindBuffer[offset];
253 if (!state) {
254 return;
255 }
256 thread->rewindBufferSize -= nStates;
257 thread->rewindBufferWriteOffset = (offset + thread->rewindBufferCapacity - nStates) % thread->rewindBufferCapacity;
258 GBADeserialize(thread->gba, state);
259}