1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396 | /**************************************************************************/
/* multiplayer_api.cpp */
/**************************************************************************/
/* This file is part of: */
/* GODOT ENGINE */
/* https://godotengine.org */
/**************************************************************************/
/* Copyright (c) 2014-present Godot Engine contributors (see AUTHORS.md). */
/* Copyright (c) 2007-2014 Juan Linietsky, Ariel Manzur. */
/* */
/* Permission is hereby granted, free of charge, to any person obtaining */
/* a copy of this software and associated documentation files (the */
/* "Software"), to deal in the Software without restriction, including */
/* without limitation the rights to use, copy, modify, merge, publish, */
/* distribute, sublicense, and/or sell copies of the Software, and to */
/* permit persons to whom the Software is furnished to do so, subject to */
/* the following conditions: */
/* */
/* The above copyright notice and this permission notice shall be */
/* included in all copies or substantial portions of the Software. */
/* */
/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, */
/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF */
/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. */
/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY */
/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, */
/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE */
/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */
/**************************************************************************/
#include "multiplayer_api.h"
#include "core/debugger/engine_debugger.h"
#include "core/io/marshalls.h"
#include <stdint.h>
#ifdef DEBUG_ENABLED
#include "core/os/os.h"
#endif
StringName MultiplayerAPI::default_interface;
void MultiplayerAPI::set_default_interface(const StringName &p_interface) {
ERR_FAIL_COND_MSG(!ClassDB::is_parent_class(p_interface, MultiplayerAPI::get_class_static()), vformat("Can't make %s the default multiplayer interface since it does not extend MultiplayerAPI.", p_interface));
default_interface = StringName(p_interface, true);
}
StringName MultiplayerAPI::get_default_interface() {
return default_interface;
}
Ref<MultiplayerAPI> MultiplayerAPI::create_default_interface() {
if (default_interface != StringName()) {
return Ref<MultiplayerAPI>(Object::cast_to<MultiplayerAPI>(ClassDB::instantiate(default_interface)));
}
return Ref<MultiplayerAPI>(memnew(MultiplayerAPIExtension));
}
// The variant is compressed and encoded; The first byte contains all the meta
// information and the format is:
// - The first LSB 6 bits are used for the variant type.
// - The next two bits are used to store the encoding mode.
// - Boolean values uses the encoding mode to store the value.
#define VARIANT_META_TYPE_MASK 0x3F
#define VARIANT_META_EMODE_MASK 0xC0
#define VARIANT_META_BOOL_MASK 0x80
#define ENCODE_8 0 << 6
#define ENCODE_16 1 << 6
#define ENCODE_32 2 << 6
#define ENCODE_64 3 << 6
Error MultiplayerAPI::encode_and_compress_variant(const Variant &p_variant, uint8_t *r_buffer, int &r_len, bool p_allow_object_decoding) {
// Unreachable because `VARIANT_MAX` == 38 and `ENCODE_VARIANT_MASK` == 77
CRASH_COND(p_variant.get_type() > VARIANT_META_TYPE_MASK);
uint8_t *buf = r_buffer;
r_len = 0;
uint8_t encode_mode = 0;<--- The scope of the variable 'encode_mode' can be reduced. [+]The scope of the variable 'encode_mode' can be reduced. Warning: Be careful when fixing this message, especially when there are inner loops. Here is an example where cppcheck will write that the scope for 'i' can be reduced:
void f(int x)
{
int i = 0;
if (x) {
// it's safe to move 'int i = 0;' here
for (int n = 0; n < 10; ++n) {
// it is possible but not safe to move 'int i = 0;' here
do_something(&i);
}
}
}
When you see this message it is always safe to reduce the variable scope 1 level.
switch (p_variant.get_type()) {
case Variant::BOOL: {
if (buf) {
// We don't use encode_mode for booleans, so we can use it to store the value.
buf[0] = (p_variant.operator bool()) ? (1 << 7) : 0;
buf[0] |= p_variant.get_type();
}
r_len += 1;
} break;
case Variant::INT: {
if (buf) {
// Reserve the first byte for the meta.
buf += 1;
}
r_len += 1;
int64_t val = p_variant;
if (val <= (int64_t)INT8_MAX && val >= (int64_t)INT8_MIN) {
// Use 8 bit
encode_mode = ENCODE_8;
if (buf) {
buf[0] = val;
}
r_len += 1;
} else if (val <= (int64_t)INT16_MAX && val >= (int64_t)INT16_MIN) {
// Use 16 bit
encode_mode = ENCODE_16;
if (buf) {
encode_uint16(val, buf);
}
r_len += 2;
} else if (val <= (int64_t)INT32_MAX && val >= (int64_t)INT32_MIN) {
// Use 32 bit
encode_mode = ENCODE_32;
if (buf) {
encode_uint32(val, buf);
}
r_len += 4;
} else {
// Use 64 bit
encode_mode = ENCODE_64;
if (buf) {
encode_uint64(val, buf);
}
r_len += 8;
}
// Store the meta
if (buf) {
buf -= 1;
buf[0] = encode_mode | p_variant.get_type();
}
} break;
default:
// Any other case is not yet compressed.
Error err = encode_variant(p_variant, r_buffer, r_len, p_allow_object_decoding);
if (err != OK) {
return err;
}
if (r_buffer) {
// The first byte is not used by the marshaling, so store the type
// so we know how to decompress and decode this variant.
r_buffer[0] = p_variant.get_type();
}
}
return OK;
}
Error MultiplayerAPI::decode_and_decompress_variant(Variant &r_variant, const uint8_t *p_buffer, int p_len, int *r_len, bool p_allow_object_decoding) {
const uint8_t *buf = p_buffer;
int len = p_len;
ERR_FAIL_COND_V(len < 1, ERR_INVALID_DATA);
uint8_t type = buf[0] & VARIANT_META_TYPE_MASK;
uint8_t encode_mode = buf[0] & VARIANT_META_EMODE_MASK;
ERR_FAIL_COND_V(type >= Variant::VARIANT_MAX, ERR_INVALID_DATA);
switch (type) {
case Variant::BOOL: {
bool val = (buf[0] & VARIANT_META_BOOL_MASK) > 0;
r_variant = val;
if (r_len) {
*r_len = 1;
}
} break;
case Variant::INT: {
buf += 1;
len -= 1;
if (r_len) {
*r_len = 1;
}
if (encode_mode == ENCODE_8) {
// 8 bits.
ERR_FAIL_COND_V(len < 1, ERR_INVALID_DATA);
int8_t val = buf[0];
r_variant = val;
if (r_len) {
(*r_len) += 1;
}
} else if (encode_mode == ENCODE_16) {
// 16 bits.
ERR_FAIL_COND_V(len < 2, ERR_INVALID_DATA);
int16_t val = decode_uint16(buf);
r_variant = val;
if (r_len) {
(*r_len) += 2;
}
} else if (encode_mode == ENCODE_32) {
// 32 bits.
ERR_FAIL_COND_V(len < 4, ERR_INVALID_DATA);
int32_t val = decode_uint32(buf);
r_variant = val;
if (r_len) {
(*r_len) += 4;
}
} else {
// 64 bits.
ERR_FAIL_COND_V(len < 8, ERR_INVALID_DATA);
int64_t val = decode_uint64(buf);
r_variant = val;
if (r_len) {
(*r_len) += 8;
}
}
} break;
default:
Error err = decode_variant(r_variant, p_buffer, p_len, r_len, p_allow_object_decoding);
if (err != OK) {
return err;
}
}
return OK;
}
Error MultiplayerAPI::encode_and_compress_variants(const Variant **p_variants, int p_count, uint8_t *p_buffer, int &r_len, bool *r_raw, bool p_allow_object_decoding) {
r_len = 0;
int size = 0;
if (p_count == 0) {
if (r_raw) {
*r_raw = true;
}
return OK;
}
// Try raw encoding optimization.
if (r_raw && p_count == 1) {
*r_raw = false;
const Variant &v = *(p_variants[0]);
if (v.get_type() == Variant::PACKED_BYTE_ARRAY) {
*r_raw = true;
const PackedByteArray pba = v;
if (p_buffer) {
memcpy(p_buffer, pba.ptr(), pba.size());
}
r_len += pba.size();
} else {
encode_and_compress_variant(v, p_buffer, size, p_allow_object_decoding);
r_len += size;
}
return OK;
}
// Regular encoding.
for (int i = 0; i < p_count; i++) {
const Variant &v = *(p_variants[i]);
encode_and_compress_variant(v, p_buffer ? p_buffer + r_len : nullptr, size, p_allow_object_decoding);
r_len += size;
}
return OK;
}
Error MultiplayerAPI::decode_and_decompress_variants(Vector<Variant> &r_variants, const uint8_t *p_buffer, int p_len, int &r_len, bool p_raw, bool p_allow_object_decoding) {
r_len = 0;
int argc = r_variants.size();
if (argc == 0 && p_raw) {
return OK;
}
ERR_FAIL_COND_V(p_raw && argc != 1, ERR_INVALID_DATA);
if (p_raw) {
r_len = p_len;
PackedByteArray pba;
pba.resize(p_len);
memcpy(pba.ptrw(), p_buffer, p_len);
r_variants.write[0] = pba;
return OK;
}
for (int i = 0; i < argc; i++) {
ERR_FAIL_COND_V_MSG(r_len >= p_len, ERR_INVALID_DATA, "Invalid packet received. Size too small.");
int vlen;
Error err = MultiplayerAPI::decode_and_decompress_variant(r_variants.write[i], &p_buffer[r_len], p_len - r_len, &vlen, p_allow_object_decoding);
ERR_FAIL_COND_V_MSG(err != OK, err, "Invalid packet received. Unable to decode state variable.");
r_len += vlen;
}
return OK;
}
Error MultiplayerAPI::_rpc_bind(int p_peer, Object *p_object, const StringName &p_method, Array p_args) {
Vector<Variant> args;
Vector<const Variant *> argsp;
args.resize(p_args.size());
argsp.resize(p_args.size());
Variant *ptr = args.ptrw();
const Variant **pptr = argsp.ptrw();
for (int i = 0; i < p_args.size(); i++) {
ptr[i] = p_args[i];
pptr[i] = &ptr[i];
}
return rpcp(p_object, p_peer, p_method, argsp.size() ? argsp.ptrw() : nullptr, argsp.size());
}
void MultiplayerAPI::_bind_methods() {
ClassDB::bind_method(D_METHOD("has_multiplayer_peer"), &MultiplayerAPI::has_multiplayer_peer);
ClassDB::bind_method(D_METHOD("get_multiplayer_peer"), &MultiplayerAPI::get_multiplayer_peer);
ClassDB::bind_method(D_METHOD("set_multiplayer_peer", "peer"), &MultiplayerAPI::set_multiplayer_peer);
ClassDB::bind_method(D_METHOD("get_unique_id"), &MultiplayerAPI::get_unique_id);
ClassDB::bind_method(D_METHOD("is_server"), &MultiplayerAPI::is_server);
ClassDB::bind_method(D_METHOD("get_remote_sender_id"), &MultiplayerAPI::get_remote_sender_id);
ClassDB::bind_method(D_METHOD("poll"), &MultiplayerAPI::poll);
ClassDB::bind_method(D_METHOD("rpc", "peer", "object", "method", "arguments"), &MultiplayerAPI::_rpc_bind, DEFVAL(Array()));
ClassDB::bind_method(D_METHOD("object_configuration_add", "object", "configuration"), &MultiplayerAPI::object_configuration_add);
ClassDB::bind_method(D_METHOD("object_configuration_remove", "object", "configuration"), &MultiplayerAPI::object_configuration_remove);
ClassDB::bind_method(D_METHOD("get_peers"), &MultiplayerAPI::get_peer_ids);
ADD_PROPERTY(PropertyInfo(Variant::OBJECT, "multiplayer_peer", PROPERTY_HINT_RESOURCE_TYPE, "MultiplayerPeer", PROPERTY_USAGE_NONE), "set_multiplayer_peer", "get_multiplayer_peer");
ClassDB::bind_static_method("MultiplayerAPI", D_METHOD("set_default_interface", "interface_name"), &MultiplayerAPI::set_default_interface);
ClassDB::bind_static_method("MultiplayerAPI", D_METHOD("get_default_interface"), &MultiplayerAPI::get_default_interface);
ClassDB::bind_static_method("MultiplayerAPI", D_METHOD("create_default_interface"), &MultiplayerAPI::create_default_interface);
ADD_SIGNAL(MethodInfo("peer_connected", PropertyInfo(Variant::INT, "id")));
ADD_SIGNAL(MethodInfo("peer_disconnected", PropertyInfo(Variant::INT, "id")));
ADD_SIGNAL(MethodInfo("connected_to_server"));
ADD_SIGNAL(MethodInfo("connection_failed"));
ADD_SIGNAL(MethodInfo("server_disconnected"));
BIND_ENUM_CONSTANT(RPC_MODE_DISABLED);
BIND_ENUM_CONSTANT(RPC_MODE_ANY_PEER);
BIND_ENUM_CONSTANT(RPC_MODE_AUTHORITY);
}
/// MultiplayerAPIExtension
Error MultiplayerAPIExtension::poll() {
Error err = OK;
GDVIRTUAL_CALL(_poll, err);
return err;
}
void MultiplayerAPIExtension::set_multiplayer_peer(const Ref<MultiplayerPeer> &p_peer) {
GDVIRTUAL_CALL(_set_multiplayer_peer, p_peer);
}
Ref<MultiplayerPeer> MultiplayerAPIExtension::get_multiplayer_peer() {
Ref<MultiplayerPeer> peer;
GDVIRTUAL_CALL(_get_multiplayer_peer, peer);
return peer;
}
int MultiplayerAPIExtension::get_unique_id() {
int id = 1;
GDVIRTUAL_CALL(_get_unique_id, id);
return id;
}
Vector<int> MultiplayerAPIExtension::get_peer_ids() {
Vector<int> ids;
GDVIRTUAL_CALL(_get_peer_ids, ids);
return ids;
}
Error MultiplayerAPIExtension::rpcp(Object *p_obj, int p_peer_id, const StringName &p_method, const Variant **p_arg, int p_argcount) {
if (!GDVIRTUAL_IS_OVERRIDDEN(_rpc)) {
return ERR_UNAVAILABLE;
}
Array args;
for (int i = 0; i < p_argcount; i++) {
args.push_back(*p_arg[i]);
}
Error ret = FAILED;
GDVIRTUAL_CALL(_rpc, p_peer_id, p_obj, p_method, args, ret);
return ret;
}
int MultiplayerAPIExtension::get_remote_sender_id() {
int id = 0;
GDVIRTUAL_CALL(_get_remote_sender_id, id);
return id;
}
Error MultiplayerAPIExtension::object_configuration_add(Object *p_object, Variant p_config) {
Error err = ERR_UNAVAILABLE;
GDVIRTUAL_CALL(_object_configuration_add, p_object, p_config, err);
return err;
}
Error MultiplayerAPIExtension::object_configuration_remove(Object *p_object, Variant p_config) {
Error err = ERR_UNAVAILABLE;
GDVIRTUAL_CALL(_object_configuration_remove, p_object, p_config, err);
return err;
}
void MultiplayerAPIExtension::_bind_methods() {
GDVIRTUAL_BIND(_poll);
GDVIRTUAL_BIND(_set_multiplayer_peer, "multiplayer_peer");
GDVIRTUAL_BIND(_get_multiplayer_peer);
GDVIRTUAL_BIND(_get_unique_id);
GDVIRTUAL_BIND(_get_peer_ids);
GDVIRTUAL_BIND(_rpc, "peer", "object", "method", "args");
GDVIRTUAL_BIND(_get_remote_sender_id);
GDVIRTUAL_BIND(_object_configuration_add, "object", "configuration");
GDVIRTUAL_BIND(_object_configuration_remove, "object", "configuration");
}
|