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Fix a crash on Android with Align2Npot2 (#8070)
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1 /*
2 Minetest
3 Copyright (C) 2013 celeron55, Perttu Ahola <celeron55@gmail.com>
4
5 This program is free software; you can redistribute it and/or modify
6 it under the terms of the GNU Lesser General Public License as published by
7 the Free Software Foundation; either version 2.1 of the License, or
8 (at your option) any later version.
9
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13 GNU Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public License along
16 with this program; if not, write to the Free Software Foundation, Inc.,
17 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
18 */
19
20 #include "mapblock.h"
21
22 #include <sstream>
23 #include "map.h"
24 #include "light.h"
25 #include "nodedef.h"
26 #include "nodemetadata.h"
27 #include "gamedef.h"
28 #include "log.h"
29 #include "nameidmapping.h"
30 #include "content_mapnode.h" // For legacy name-id mapping
31 #include "content_nodemeta.h" // For legacy deserialization
32 #include "serialization.h"
33 #ifndef SERVER
34 #include "client/mapblock_mesh.h"
35 #endif
36 #include "porting.h"
37 #include "util/string.h"
38 #include "util/serialize.h"
39 #include "util/basic_macros.h"
40
41 static const char *modified_reason_strings[] = {
42         "initial",
43         "reallocate",
44         "setIsUnderground",
45         "setLightingExpired",
46         "setGenerated",
47         "setNode",
48         "setNodeNoCheck",
49         "setTimestamp",
50         "NodeMetaRef::reportMetadataChange",
51         "clearAllObjects",
52         "Timestamp expired (step)",
53         "addActiveObjectRaw",
54         "removeRemovedObjects/remove",
55         "removeRemovedObjects/deactivate",
56         "Stored list cleared in activateObjects due to overflow",
57         "deactivateFarObjects: Static data moved in",
58         "deactivateFarObjects: Static data moved out",
59         "deactivateFarObjects: Static data changed considerably",
60         "finishBlockMake: expireDayNightDiff",
61         "unknown",
62 };
63
64
65 /*
66         MapBlock
67 */
68
69 MapBlock::MapBlock(Map *parent, v3s16 pos, IGameDef *gamedef, bool dummy):
70                 m_parent(parent),
71                 m_pos(pos),
72                 m_pos_relative(pos * MAP_BLOCKSIZE),
73                 m_gamedef(gamedef)
74 {
75         if (!dummy)
76                 reallocate();
77 }
78
79 MapBlock::~MapBlock()
80 {
81 #ifndef SERVER
82         {
83                 delete mesh;
84                 mesh = nullptr;
85         }
86 #endif
87
88         delete[] data;
89 }
90
91 bool MapBlock::isValidPositionParent(v3s16 p)
92 {
93         if (isValidPosition(p)) {
94                 return true;
95         }
96
97         return m_parent->isValidPosition(getPosRelative() + p);
98 }
99
100 MapNode MapBlock::getNodeParent(v3s16 p, bool *is_valid_position)
101 {
102         if (!isValidPosition(p))
103                 return m_parent->getNodeNoEx(getPosRelative() + p, is_valid_position);
104
105         if (!data) {
106                 if (is_valid_position)
107                         *is_valid_position = false;
108                 return {CONTENT_IGNORE};
109         }
110         if (is_valid_position)
111                 *is_valid_position = true;
112         return data[p.Z * zstride + p.Y * ystride + p.X];
113 }
114
115 std::string MapBlock::getModifiedReasonString()
116 {
117         std::string reason;
118
119         const u32 ubound = MYMIN(sizeof(m_modified_reason) * CHAR_BIT,
120                 ARRLEN(modified_reason_strings));
121
122         for (u32 i = 0; i != ubound; i++) {
123                 if ((m_modified_reason & (1 << i)) == 0)
124                         continue;
125
126                 reason += modified_reason_strings[i];
127                 reason += ", ";
128         }
129
130         if (reason.length() > 2)
131                 reason.resize(reason.length() - 2);
132
133         return reason;
134 }
135
136
137 void MapBlock::copyTo(VoxelManipulator &dst)
138 {
139         v3s16 data_size(MAP_BLOCKSIZE, MAP_BLOCKSIZE, MAP_BLOCKSIZE);
140         VoxelArea data_area(v3s16(0,0,0), data_size - v3s16(1,1,1));
141
142         // Copy from data to VoxelManipulator
143         dst.copyFrom(data, data_area, v3s16(0,0,0),
144                         getPosRelative(), data_size);
145 }
146
147 void MapBlock::copyFrom(VoxelManipulator &dst)
148 {
149         v3s16 data_size(MAP_BLOCKSIZE, MAP_BLOCKSIZE, MAP_BLOCKSIZE);
150         VoxelArea data_area(v3s16(0,0,0), data_size - v3s16(1,1,1));
151
152         // Copy from VoxelManipulator to data
153         dst.copyTo(data, data_area, v3s16(0,0,0),
154                         getPosRelative(), data_size);
155 }
156
157 void MapBlock::actuallyUpdateDayNightDiff()
158 {
159         const NodeDefManager *nodemgr = m_gamedef->ndef();
160
161         // Running this function un-expires m_day_night_differs
162         m_day_night_differs_expired = false;
163
164         if (!data) {
165                 m_day_night_differs = false;
166                 return;
167         }
168
169         bool differs = false;
170
171         /*
172                 Check if any lighting value differs
173         */
174
175         MapNode previous_n(CONTENT_IGNORE);
176         for (u32 i = 0; i < nodecount; i++) {
177                 MapNode n = data[i];
178
179                 // If node is identical to previous node, don't verify if it differs
180                 if (n == previous_n)
181                         continue;
182
183                 differs = !n.isLightDayNightEq(nodemgr);
184                 if (differs)
185                         break;
186                 previous_n = n;
187         }
188
189         /*
190                 If some lighting values differ, check if the whole thing is
191                 just air. If it is just air, differs = false
192         */
193         if (differs) {
194                 bool only_air = true;
195                 for (u32 i = 0; i < nodecount; i++) {
196                         MapNode &n = data[i];
197                         if (n.getContent() != CONTENT_AIR) {
198                                 only_air = false;
199                                 break;
200                         }
201                 }
202                 if (only_air)
203                         differs = false;
204         }
205
206         // Set member variable
207         m_day_night_differs = differs;
208 }
209
210 void MapBlock::expireDayNightDiff()
211 {
212         if (!data) {
213                 m_day_night_differs = false;
214                 m_day_night_differs_expired = false;
215                 return;
216         }
217
218         m_day_night_differs_expired = true;
219 }
220
221 s16 MapBlock::getGroundLevel(v2s16 p2d)
222 {
223         if(isDummy())
224                 return -3;
225         try
226         {
227                 s16 y = MAP_BLOCKSIZE-1;
228                 for(; y>=0; y--)
229                 {
230                         MapNode n = getNodeRef(p2d.X, y, p2d.Y);
231                         if (m_gamedef->ndef()->get(n).walkable) {
232                                 if(y == MAP_BLOCKSIZE-1)
233                                         return -2;
234
235                                 return y;
236                         }
237                 }
238                 return -1;
239         }
240         catch(InvalidPositionException &e)
241         {
242                 return -3;
243         }
244 }
245
246 /*
247         Serialization
248 */
249 // List relevant id-name pairs for ids in the block using nodedef
250 // Renumbers the content IDs (starting at 0 and incrementing
251 // use static memory requires about 65535 * sizeof(int) ram in order to be
252 // sure we can handle all content ids. But it's absolutely worth it as it's
253 // a speedup of 4 for one of the major time consuming functions on storing
254 // mapblocks.
255 static content_t getBlockNodeIdMapping_mapping[USHRT_MAX + 1];
256 static void getBlockNodeIdMapping(NameIdMapping *nimap, MapNode *nodes,
257         const NodeDefManager *nodedef)
258 {
259         memset(getBlockNodeIdMapping_mapping, 0xFF, (USHRT_MAX + 1) * sizeof(content_t));
260
261         std::set<content_t> unknown_contents;
262         content_t id_counter = 0;
263         for (u32 i = 0; i < MapBlock::nodecount; i++) {
264                 content_t global_id = nodes[i].getContent();
265                 content_t id = CONTENT_IGNORE;
266
267                 // Try to find an existing mapping
268                 if (getBlockNodeIdMapping_mapping[global_id] != 0xFFFF) {
269                         id = getBlockNodeIdMapping_mapping[global_id];
270                 }
271                 else
272                 {
273                         // We have to assign a new mapping
274                         id = id_counter++;
275                         getBlockNodeIdMapping_mapping[global_id] = id;
276
277                         const ContentFeatures &f = nodedef->get(global_id);
278                         const std::string &name = f.name;
279                         if (name.empty())
280                                 unknown_contents.insert(global_id);
281                         else
282                                 nimap->set(id, name);
283                 }
284
285                 // Update the MapNode
286                 nodes[i].setContent(id);
287         }
288         for (u16 unknown_content : unknown_contents) {
289                 errorstream << "getBlockNodeIdMapping(): IGNORING ERROR: "
290                                 << "Name for node id " << unknown_content << " not known" << std::endl;
291         }
292 }
293 // Correct ids in the block to match nodedef based on names.
294 // Unknown ones are added to nodedef.
295 // Will not update itself to match id-name pairs in nodedef.
296 static void correctBlockNodeIds(const NameIdMapping *nimap, MapNode *nodes,
297                 IGameDef *gamedef)
298 {
299         const NodeDefManager *nodedef = gamedef->ndef();
300         // This means the block contains incorrect ids, and we contain
301         // the information to convert those to names.
302         // nodedef contains information to convert our names to globally
303         // correct ids.
304         std::unordered_set<content_t> unnamed_contents;
305         std::unordered_set<std::string> unallocatable_contents;
306
307         bool previous_exists = false;
308         content_t previous_local_id = CONTENT_IGNORE;
309         content_t previous_global_id = CONTENT_IGNORE;
310
311         for (u32 i = 0; i < MapBlock::nodecount; i++) {
312                 content_t local_id = nodes[i].getContent();
313                 // If previous node local_id was found and same than before, don't lookup maps
314                 // apply directly previous resolved id
315                 // This permits to massively improve loading performance when nodes are similar
316                 // example: default:air, default:stone are massively present
317                 if (previous_exists && local_id == previous_local_id) {
318                         nodes[i].setContent(previous_global_id);
319                         continue;
320                 }
321
322                 std::string name;
323                 if (!nimap->getName(local_id, name)) {
324                         unnamed_contents.insert(local_id);
325                         previous_exists = false;
326                         continue;
327                 }
328
329                 content_t global_id;
330                 if (!nodedef->getId(name, global_id)) {
331                         global_id = gamedef->allocateUnknownNodeId(name);
332                         if (global_id == CONTENT_IGNORE) {
333                                 unallocatable_contents.insert(name);
334                                 previous_exists = false;
335                                 continue;
336                         }
337                 }
338                 nodes[i].setContent(global_id);
339
340                 // Save previous node local_id & global_id result
341                 previous_local_id = local_id;
342                 previous_global_id = global_id;
343                 previous_exists = true;
344         }
345
346         for (const content_t c: unnamed_contents) {
347                 errorstream << "correctBlockNodeIds(): IGNORING ERROR: "
348                                 << "Block contains id " << c
349                                 << " with no name mapping" << std::endl;
350         }
351         for (const std::string &node_name: unallocatable_contents) {
352                 errorstream << "correctBlockNodeIds(): IGNORING ERROR: "
353                                 << "Could not allocate global id for node name \""
354                                 << node_name << "\"" << std::endl;
355         }
356 }
357
358 void MapBlock::serialize(std::ostream &os, u8 version, bool disk)
359 {
360         if(!ser_ver_supported(version))
361                 throw VersionMismatchException("ERROR: MapBlock format not supported");
362
363         if (!data)
364                 throw SerializationError("ERROR: Not writing dummy block.");
365
366         FATAL_ERROR_IF(version < SER_FMT_VER_LOWEST_WRITE, "Serialisation version error");
367
368         // First byte
369         u8 flags = 0;
370         if(is_underground)
371                 flags |= 0x01;
372         if(getDayNightDiff())
373                 flags |= 0x02;
374         if (!m_generated)
375                 flags |= 0x08;
376         writeU8(os, flags);
377         if (version >= 27) {
378                 writeU16(os, m_lighting_complete);
379         }
380
381         /*
382                 Bulk node data
383         */
384         NameIdMapping nimap;
385         if(disk)
386         {
387                 MapNode *tmp_nodes = new MapNode[nodecount];
388                 for(u32 i=0; i<nodecount; i++)
389                         tmp_nodes[i] = data[i];
390                 getBlockNodeIdMapping(&nimap, tmp_nodes, m_gamedef->ndef());
391
392                 u8 content_width = 2;
393                 u8 params_width = 2;
394                 writeU8(os, content_width);
395                 writeU8(os, params_width);
396                 MapNode::serializeBulk(os, version, tmp_nodes, nodecount,
397                                 content_width, params_width, true);
398                 delete[] tmp_nodes;
399         }
400         else
401         {
402                 u8 content_width = 2;
403                 u8 params_width = 2;
404                 writeU8(os, content_width);
405                 writeU8(os, params_width);
406                 MapNode::serializeBulk(os, version, data, nodecount,
407                                 content_width, params_width, true);
408         }
409
410         /*
411                 Node metadata
412         */
413         std::ostringstream oss(std::ios_base::binary);
414         m_node_metadata.serialize(oss, version, disk);
415         compressZlib(oss.str(), os);
416
417         /*
418                 Data that goes to disk, but not the network
419         */
420         if(disk)
421         {
422                 if(version <= 24){
423                         // Node timers
424                         m_node_timers.serialize(os, version);
425                 }
426
427                 // Static objects
428                 m_static_objects.serialize(os);
429
430                 // Timestamp
431                 writeU32(os, getTimestamp());
432
433                 // Write block-specific node definition id mapping
434                 nimap.serialize(os);
435
436                 if(version >= 25){
437                         // Node timers
438                         m_node_timers.serialize(os, version);
439                 }
440         }
441 }
442
443 void MapBlock::serializeNetworkSpecific(std::ostream &os)
444 {
445         if (!data) {
446                 throw SerializationError("ERROR: Not writing dummy block.");
447         }
448
449         writeU8(os, 2); // version
450 }
451
452 void MapBlock::deSerialize(std::istream &is, u8 version, bool disk)
453 {
454         if(!ser_ver_supported(version))
455                 throw VersionMismatchException("ERROR: MapBlock format not supported");
456
457         TRACESTREAM(<<"MapBlock::deSerialize "<<PP(getPos())<<std::endl);
458
459         m_day_night_differs_expired = false;
460
461         if(version <= 21)
462         {
463                 deSerialize_pre22(is, version, disk);
464                 return;
465         }
466
467         u8 flags = readU8(is);
468         is_underground = (flags & 0x01) != 0;
469         m_day_night_differs = (flags & 0x02) != 0;
470         if (version < 27)
471                 m_lighting_complete = 0xFFFF;
472         else
473                 m_lighting_complete = readU16(is);
474         m_generated = (flags & 0x08) == 0;
475
476         /*
477                 Bulk node data
478         */
479         TRACESTREAM(<<"MapBlock::deSerialize "<<PP(getPos())
480                         <<": Bulk node data"<<std::endl);
481         u8 content_width = readU8(is);
482         u8 params_width = readU8(is);
483         if(content_width != 1 && content_width != 2)
484                 throw SerializationError("MapBlock::deSerialize(): invalid content_width");
485         if(params_width != 2)
486                 throw SerializationError("MapBlock::deSerialize(): invalid params_width");
487         MapNode::deSerializeBulk(is, version, data, nodecount,
488                         content_width, params_width, true);
489
490         /*
491                 NodeMetadata
492         */
493         TRACESTREAM(<<"MapBlock::deSerialize "<<PP(getPos())
494                         <<": Node metadata"<<std::endl);
495         // Ignore errors
496         try {
497                 std::ostringstream oss(std::ios_base::binary);
498                 decompressZlib(is, oss);
499                 std::istringstream iss(oss.str(), std::ios_base::binary);
500                 if (version >= 23)
501                         m_node_metadata.deSerialize(iss, m_gamedef->idef());
502                 else
503                         content_nodemeta_deserialize_legacy(iss,
504                                 &m_node_metadata, &m_node_timers,
505                                 m_gamedef->idef());
506         } catch(SerializationError &e) {
507                 warningstream<<"MapBlock::deSerialize(): Ignoring an error"
508                                 <<" while deserializing node metadata at ("
509                                 <<PP(getPos())<<": "<<e.what()<<std::endl;
510         }
511
512         /*
513                 Data that is only on disk
514         */
515         if(disk)
516         {
517                 // Node timers
518                 if(version == 23){
519                         // Read unused zero
520                         readU8(is);
521                 }
522                 if(version == 24){
523                         TRACESTREAM(<<"MapBlock::deSerialize "<<PP(getPos())
524                                         <<": Node timers (ver==24)"<<std::endl);
525                         m_node_timers.deSerialize(is, version);
526                 }
527
528                 // Static objects
529                 TRACESTREAM(<<"MapBlock::deSerialize "<<PP(getPos())
530                                 <<": Static objects"<<std::endl);
531                 m_static_objects.deSerialize(is);
532
533                 // Timestamp
534                 TRACESTREAM(<<"MapBlock::deSerialize "<<PP(getPos())
535                                 <<": Timestamp"<<std::endl);
536                 setTimestamp(readU32(is));
537                 m_disk_timestamp = m_timestamp;
538
539                 // Dynamically re-set ids based on node names
540                 TRACESTREAM(<<"MapBlock::deSerialize "<<PP(getPos())
541                                 <<": NameIdMapping"<<std::endl);
542                 NameIdMapping nimap;
543                 nimap.deSerialize(is);
544                 correctBlockNodeIds(&nimap, data, m_gamedef);
545
546                 if(version >= 25){
547                         TRACESTREAM(<<"MapBlock::deSerialize "<<PP(getPos())
548                                         <<": Node timers (ver>=25)"<<std::endl);
549                         m_node_timers.deSerialize(is, version);
550                 }
551         }
552
553         TRACESTREAM(<<"MapBlock::deSerialize "<<PP(getPos())
554                         <<": Done."<<std::endl);
555 }
556
557 void MapBlock::deSerializeNetworkSpecific(std::istream &is)
558 {
559         try {
560                 const u8 version = readU8(is);
561                 //if(version != 1)
562                 //      throw SerializationError("unsupported MapBlock version");
563
564         } catch(SerializationError &e) {
565                 warningstream<<"MapBlock::deSerializeNetworkSpecific(): Ignoring an error"
566                                 <<": "<<e.what()<<std::endl;
567         }
568 }
569
570 /*
571         Legacy serialization
572 */
573
574 void MapBlock::deSerialize_pre22(std::istream &is, u8 version, bool disk)
575 {
576         // Initialize default flags
577         is_underground = false;
578         m_day_night_differs = false;
579         m_lighting_complete = 0xFFFF;
580         m_generated = true;
581
582         // Make a temporary buffer
583         u32 ser_length = MapNode::serializedLength(version);
584         SharedBuffer<u8> databuf_nodelist(nodecount * ser_length);
585
586         // These have no compression
587         if (version <= 3 || version == 5 || version == 6) {
588                 char tmp;
589                 is.read(&tmp, 1);
590                 if (is.gcount() != 1)
591                         throw SerializationError(std::string(FUNCTION_NAME)
592                                 + ": not enough input data");
593                 is_underground = tmp;
594                 is.read((char *)*databuf_nodelist, nodecount * ser_length);
595                 if ((u32)is.gcount() != nodecount * ser_length)
596                         throw SerializationError(std::string(FUNCTION_NAME)
597                                 + ": not enough input data");
598         } else if (version <= 10) {
599                 u8 t8;
600                 is.read((char *)&t8, 1);
601                 is_underground = t8;
602
603                 {
604                         // Uncompress and set material data
605                         std::ostringstream os(std::ios_base::binary);
606                         decompress(is, os, version);
607                         std::string s = os.str();
608                         if (s.size() != nodecount)
609                                 throw SerializationError(std::string(FUNCTION_NAME)
610                                         + ": not enough input data");
611                         for (u32 i = 0; i < s.size(); i++) {
612                                 databuf_nodelist[i*ser_length] = s[i];
613                         }
614                 }
615                 {
616                         // Uncompress and set param data
617                         std::ostringstream os(std::ios_base::binary);
618                         decompress(is, os, version);
619                         std::string s = os.str();
620                         if (s.size() != nodecount)
621                                 throw SerializationError(std::string(FUNCTION_NAME)
622                                         + ": not enough input data");
623                         for (u32 i = 0; i < s.size(); i++) {
624                                 databuf_nodelist[i*ser_length + 1] = s[i];
625                         }
626                 }
627
628                 if (version >= 10) {
629                         // Uncompress and set param2 data
630                         std::ostringstream os(std::ios_base::binary);
631                         decompress(is, os, version);
632                         std::string s = os.str();
633                         if (s.size() != nodecount)
634                                 throw SerializationError(std::string(FUNCTION_NAME)
635                                         + ": not enough input data");
636                         for (u32 i = 0; i < s.size(); i++) {
637                                 databuf_nodelist[i*ser_length + 2] = s[i];
638                         }
639                 }
640         } else { // All other versions (10 to 21)
641                 u8 flags;
642                 is.read((char*)&flags, 1);
643                 is_underground = (flags & 0x01) != 0;
644                 m_day_night_differs = (flags & 0x02) != 0;
645                 if(version >= 18)
646                         m_generated = (flags & 0x08) == 0;
647
648                 // Uncompress data
649                 std::ostringstream os(std::ios_base::binary);
650                 decompress(is, os, version);
651                 std::string s = os.str();
652                 if (s.size() != nodecount * 3)
653                         throw SerializationError(std::string(FUNCTION_NAME)
654                                 + ": decompress resulted in size other than nodecount*3");
655
656                 // deserialize nodes from buffer
657                 for (u32 i = 0; i < nodecount; i++) {
658                         databuf_nodelist[i*ser_length] = s[i];
659                         databuf_nodelist[i*ser_length + 1] = s[i+nodecount];
660                         databuf_nodelist[i*ser_length + 2] = s[i+nodecount*2];
661                 }
662
663                 /*
664                         NodeMetadata
665                 */
666                 if (version >= 14) {
667                         // Ignore errors
668                         try {
669                                 if (version <= 15) {
670                                         std::string data = deSerializeString(is);
671                                         std::istringstream iss(data, std::ios_base::binary);
672                                         content_nodemeta_deserialize_legacy(iss,
673                                                 &m_node_metadata, &m_node_timers,
674                                                 m_gamedef->idef());
675                                 } else {
676                                         //std::string data = deSerializeLongString(is);
677                                         std::ostringstream oss(std::ios_base::binary);
678                                         decompressZlib(is, oss);
679                                         std::istringstream iss(oss.str(), std::ios_base::binary);
680                                         content_nodemeta_deserialize_legacy(iss,
681                                                 &m_node_metadata, &m_node_timers,
682                                                 m_gamedef->idef());
683                                 }
684                         } catch(SerializationError &e) {
685                                 warningstream<<"MapBlock::deSerialize(): Ignoring an error"
686                                                 <<" while deserializing node metadata"<<std::endl;
687                         }
688                 }
689         }
690
691         // Deserialize node data
692         for (u32 i = 0; i < nodecount; i++) {
693                 data[i].deSerialize(&databuf_nodelist[i * ser_length], version);
694         }
695
696         if (disk) {
697                 /*
698                         Versions up from 9 have block objects. (DEPRECATED)
699                 */
700                 if (version >= 9) {
701                         u16 count = readU16(is);
702                         // Not supported and length not known if count is not 0
703                         if(count != 0){
704                                 warningstream<<"MapBlock::deSerialize_pre22(): "
705                                                 <<"Ignoring stuff coming at and after MBOs"<<std::endl;
706                                 return;
707                         }
708                 }
709
710                 /*
711                         Versions up from 15 have static objects.
712                 */
713                 if (version >= 15)
714                         m_static_objects.deSerialize(is);
715
716                 // Timestamp
717                 if (version >= 17) {
718                         setTimestamp(readU32(is));
719                         m_disk_timestamp = m_timestamp;
720                 } else {
721                         setTimestamp(BLOCK_TIMESTAMP_UNDEFINED);
722                 }
723
724                 // Dynamically re-set ids based on node names
725                 NameIdMapping nimap;
726                 // If supported, read node definition id mapping
727                 if (version >= 21) {
728                         nimap.deSerialize(is);
729                 // Else set the legacy mapping
730                 } else {
731                         content_mapnode_get_name_id_mapping(&nimap);
732                 }
733                 correctBlockNodeIds(&nimap, data, m_gamedef);
734         }
735
736
737         // Legacy data changes
738         // This code has to convert from pre-22 to post-22 format.
739         const NodeDefManager *nodedef = m_gamedef->ndef();
740         for(u32 i=0; i<nodecount; i++)
741         {
742                 const ContentFeatures &f = nodedef->get(data[i].getContent());
743                 // Mineral
744                 if(nodedef->getId("default:stone") == data[i].getContent()
745                                 && data[i].getParam1() == 1)
746                 {
747                         data[i].setContent(nodedef->getId("default:stone_with_coal"));
748                         data[i].setParam1(0);
749                 }
750                 else if(nodedef->getId("default:stone") == data[i].getContent()
751                                 && data[i].getParam1() == 2)
752                 {
753                         data[i].setContent(nodedef->getId("default:stone_with_iron"));
754                         data[i].setParam1(0);
755                 }
756                 // facedir_simple
757                 if(f.legacy_facedir_simple)
758                 {
759                         data[i].setParam2(data[i].getParam1());
760                         data[i].setParam1(0);
761                 }
762                 // wall_mounted
763                 if(f.legacy_wallmounted)
764                 {
765                         u8 wallmounted_new_to_old[8] = {0x04, 0x08, 0x01, 0x02, 0x10, 0x20, 0, 0};
766                         u8 dir_old_format = data[i].getParam2();
767                         u8 dir_new_format = 0;
768                         for(u8 j=0; j<8; j++)
769                         {
770                                 if((dir_old_format & wallmounted_new_to_old[j]) != 0)
771                                 {
772                                         dir_new_format = j;
773                                         break;
774                                 }
775                         }
776                         data[i].setParam2(dir_new_format);
777                 }
778         }
779
780 }
781
782 /*
783         Get a quick string to describe what a block actually contains
784 */
785 std::string analyze_block(MapBlock *block)
786 {
787         if(block == NULL)
788                 return "NULL";
789
790         std::ostringstream desc;
791
792         v3s16 p = block->getPos();
793         char spos[25];
794         porting::mt_snprintf(spos, sizeof(spos), "(%2d,%2d,%2d), ", p.X, p.Y, p.Z);
795         desc<<spos;
796
797         switch(block->getModified())
798         {
799         case MOD_STATE_CLEAN:
800                 desc<<"CLEAN,           ";
801                 break;
802         case MOD_STATE_WRITE_AT_UNLOAD:
803                 desc<<"WRITE_AT_UNLOAD, ";
804                 break;
805         case MOD_STATE_WRITE_NEEDED:
806                 desc<<"WRITE_NEEDED,    ";
807                 break;
808         default:
809                 desc<<"unknown getModified()="+itos(block->getModified())+", ";
810         }
811
812         if(block->isGenerated())
813                 desc<<"is_gen [X], ";
814         else
815                 desc<<"is_gen [ ], ";
816
817         if(block->getIsUnderground())
818                 desc<<"is_ug [X], ";
819         else
820                 desc<<"is_ug [ ], ";
821
822         desc<<"lighting_complete: "<<block->getLightingComplete()<<", ";
823
824         if(block->isDummy())
825         {
826                 desc<<"Dummy, ";
827         }
828         else
829         {
830                 bool full_ignore = true;
831                 bool some_ignore = false;
832                 bool full_air = true;
833                 bool some_air = false;
834                 for(s16 z0=0; z0<MAP_BLOCKSIZE; z0++)
835                 for(s16 y0=0; y0<MAP_BLOCKSIZE; y0++)
836                 for(s16 x0=0; x0<MAP_BLOCKSIZE; x0++)
837                 {
838                         v3s16 p(x0,y0,z0);
839                         MapNode n = block->getNodeNoEx(p);
840                         content_t c = n.getContent();
841                         if(c == CONTENT_IGNORE)
842                                 some_ignore = true;
843                         else
844                                 full_ignore = false;
845                         if(c == CONTENT_AIR)
846                                 some_air = true;
847                         else
848                                 full_air = false;
849                 }
850
851                 desc<<"content {";
852
853                 std::ostringstream ss;
854
855                 if(full_ignore)
856                         ss<<"IGNORE (full), ";
857                 else if(some_ignore)
858                         ss<<"IGNORE, ";
859
860                 if(full_air)
861                         ss<<"AIR (full), ";
862                 else if(some_air)
863                         ss<<"AIR, ";
864
865                 if(ss.str().size()>=2)
866                         desc<<ss.str().substr(0, ss.str().size()-2);
867
868                 desc<<"}, ";
869         }
870
871         return desc.str().substr(0, desc.str().size()-2);
872 }
873
874
875 //END