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->executionMode = gba->cpu->cpsr.t ? MODE_THUMB : MODE_ARM;
74 gba->cpu->privilegeMode = gba->cpu->cpsr.priv;
75 gba->cpu->memory.setActiveRegion(gba->cpu, gba->cpu->gprs[ARM_PC]);
76
77 GBAMemoryDeserialize(&gba->memory, state);
78 GBAIODeserialize(gba, state);
79 GBAVideoDeserialize(&gba->video, state);
80 GBAAudioDeserialize(&gba->audio, state);
81
82 if (GBARRIsRecording(gba->rr)) {
83 if (state->associatedStreamId != gba->rr->streamId) {
84 GBARRLoadStream(gba->rr, state->associatedStreamId);
85 GBARRIncrementStream(gba->rr, true);
86 } else {
87 GBARRFinishSegment(gba->rr);
88 }
89 } else if (GBARRIsPlaying(gba->rr)) {
90 GBARRLoadStream(gba->rr, state->associatedStreamId);
91 GBARRSkipSegment(gba->rr);
92 }
93}
94
95static struct VFile* _getStateVf(struct GBA* gba, struct VDir* dir, int slot, bool write) {
96 char path[PATH_MAX];
97 path[PATH_MAX - 1] = '\0';
98 struct VFile* vf;
99 if (!dir) {
100 snprintf(path, PATH_MAX - 1, "%s.ss%d", gba->activeFile, slot);
101 vf = VFileOpen(path, write ? (O_CREAT | O_TRUNC | O_RDWR) : O_RDONLY);
102 } else {
103 snprintf(path, PATH_MAX - 1, "savestate.ss%d", slot);
104 vf = dir->openFile(dir, path, write ? (O_CREAT | O_TRUNC | O_RDWR) : O_RDONLY);
105 }
106 return vf;
107}
108
109static bool _savePNGState(struct GBA* gba, struct VFile* vf) {
110 unsigned stride;
111 void* pixels = 0;
112 gba->video.renderer->getPixels(gba->video.renderer, &stride, &pixels);
113 if (!pixels) {
114 return false;
115 }
116
117 struct GBASerializedState* state = GBAAllocateState();
118 png_structp png = PNGWriteOpen(vf);
119 png_infop info = PNGWriteHeader(png, VIDEO_HORIZONTAL_PIXELS, VIDEO_VERTICAL_PIXELS);
120 uLongf len = compressBound(sizeof(*state));
121 void* buffer = malloc(len);
122 if (state && png && info && buffer) {
123 GBASerialize(gba, state);
124 compress(buffer, &len, (const Bytef*) state, sizeof(*state));
125 PNGWritePixels(png, VIDEO_HORIZONTAL_PIXELS, VIDEO_VERTICAL_PIXELS, stride, pixels);
126 PNGWriteCustomChunk(png, "gbAs", len, buffer);
127 }
128 PNGWriteClose(png, info);
129 free(buffer);
130 GBADeallocateState(state);
131 return state && png && info && buffer;
132}
133
134static int _loadPNGChunkHandler(png_structp png, png_unknown_chunkp chunk) {
135 if (strcmp((const char*) chunk->name, "gbAs") != 0) {
136 return 0;
137 }
138 struct GBASerializedState state;
139 uLongf len = sizeof(state);
140 uncompress((Bytef*) &state, &len, chunk->data, chunk->size);
141 GBADeserialize(png_get_user_chunk_ptr(png), &state);
142 return 1;
143}
144
145static bool _loadPNGState(struct GBA* gba, struct VFile* vf) {
146 png_structp png = PNGReadOpen(vf, PNG_HEADER_BYTES);
147 png_infop info = png_create_info_struct(png);
148 png_infop end = png_create_info_struct(png);
149 if (!png || !info || !end) {
150 PNGReadClose(png, info, end);
151 return false;
152 }
153 uint32_t pixels[VIDEO_HORIZONTAL_PIXELS * VIDEO_VERTICAL_PIXELS * 4];
154
155 PNGInstallChunkHandler(png, gba, _loadPNGChunkHandler, "gbAs");
156 PNGReadHeader(png, info);
157 PNGReadPixels(png, info, &pixels, VIDEO_HORIZONTAL_PIXELS, VIDEO_VERTICAL_PIXELS, VIDEO_HORIZONTAL_PIXELS);
158 PNGReadFooter(png, end);
159 PNGReadClose(png, info, end);
160 gba->video.renderer->putPixels(gba->video.renderer, VIDEO_HORIZONTAL_PIXELS, pixels);
161 GBASyncPostFrame(gba->sync);
162 return true;
163}
164
165bool GBASaveState(struct GBA* gba, struct VDir* dir, int slot, bool screenshot) {
166 struct VFile* vf = _getStateVf(gba, dir, slot, true);
167 if (!vf) {
168 return false;
169 }
170 bool success = GBASaveStateNamed(gba, vf, screenshot);
171 vf->close(vf);
172 return success;
173}
174
175bool GBALoadState(struct GBA* gba, struct VDir* dir, int slot) {
176 struct VFile* vf = _getStateVf(gba, dir, slot, false);
177 if (!vf) {
178 return false;
179 }
180 bool success = GBALoadStateNamed(gba, vf);
181 vf->close(vf);
182 return success;
183}
184
185bool GBASaveStateNamed(struct GBA* gba, struct VFile* vf, bool screenshot) {
186 if (!screenshot) {
187 vf->truncate(vf, sizeof(struct GBASerializedState));
188 struct GBASerializedState* state = vf->map(vf, sizeof(struct GBASerializedState), MAP_WRITE);
189 if (!state) {
190 return false;
191 }
192 GBASerialize(gba, state);
193 vf->unmap(vf, state, sizeof(struct GBASerializedState));
194 } else {
195 return _savePNGState(gba, vf);
196 }
197 return true;
198}
199
200bool GBALoadStateNamed(struct GBA* gba, struct VFile* vf) {
201 if (!isPNG(vf)) {
202 struct GBASerializedState* state = vf->map(vf, sizeof(struct GBASerializedState), MAP_READ);
203 if (!state) {
204 return false;
205 }
206 GBADeserialize(gba, state);
207 vf->unmap(vf, state, sizeof(struct GBASerializedState));
208 } else {
209 return _loadPNGState(gba, vf);
210 }
211 return true;
212}
213
214struct GBASerializedState* GBAAllocateState(void) {
215 return anonymousMemoryMap(sizeof(struct GBASerializedState));
216}
217
218void GBADeallocateState(struct GBASerializedState* state) {
219 mappedMemoryFree(state, sizeof(struct GBASerializedState));
220}
221
222void GBARecordFrame(struct GBAThread* thread) {
223 int offset = thread->rewindBufferWriteOffset;
224 struct GBASerializedState* state = thread->rewindBuffer[offset];
225 if (!state) {
226 state = GBAAllocateState();
227 thread->rewindBuffer[offset] = state;
228 }
229 GBASerialize(thread->gba, state);
230 thread->rewindBufferSize = thread->rewindBufferSize == thread->rewindBufferCapacity ? thread->rewindBufferCapacity : thread->rewindBufferSize + 1;
231 thread->rewindBufferWriteOffset = (offset + 1) % thread->rewindBufferCapacity;
232}
233
234void GBARewind(struct GBAThread* thread, int nStates) {
235 if (nStates > thread->rewindBufferSize || nStates < 0) {
236 nStates = thread->rewindBufferSize;
237 }
238 if (nStates == 0) {
239 return;
240 }
241 int offset = thread->rewindBufferWriteOffset - nStates;
242 if (offset < 0) {
243 offset += thread->rewindBufferSize;
244 }
245 struct GBASerializedState* state = thread->rewindBuffer[offset];
246 if (!state) {
247 return;
248 }
249 thread->rewindBufferSize -= nStates;
250 thread->rewindBufferWriteOffset = (offset + thread->rewindBufferCapacity - nStates) % thread->rewindBufferCapacity;
251 GBADeserialize(thread->gba, state);
252}