reader.cc

   1 #include <reader.h>
   2 #include <alien.h>
   3
   4 #include <string>
   5 #include <assert.h>
   6
   7 namespace odc {
   8
   9 Reader::Reader(std::istream &rider): d_rider(rider), d_cancelled(false), d_readAlien(false), d_typeList(),
  10         d_state(new ReaderState()) {}
  11
  12 SHORTCHAR Reader::readSChar() {
  13         SHORTCHAR out;
  14         d_rider.read(&out, 1);
  15         return out;
  16 }
  17
  18 void Reader::readSChar(SHORTCHAR *buf, size_t len) {
  19         d_rider.read(buf, len);
  20 }
  21
  22 CHAR Reader::readLChar() {
  23         CHAR buf;
  24         char *bufPtr = (char *)&buf;
  25         d_rider.read(bufPtr, 2);
  26         if (isLittleEndian()) {
  27                 return buf;
  28         } else {
  29                 CHAR out;
  30                 char *outPtr = (char *)&out;
  31                 outPtr[0] = bufPtr[1]; outPtr[1] = bufPtr[0];
  32                 return out;
  33         }
  34 }
  35
  36 void Reader::readLChar(CHAR *buf, size_t len) {
  37         char *bufPtr = (char *)buf;
  38         int len2 = len * 2;
  39         d_rider.read(bufPtr, len2);
  40         if (isBigEndian()) {
  41                 char tmp;
  42                 for (int i = 0; i < len2; i += 2) {
  43                         tmp = bufPtr[i];
  44                         bufPtr[i] = bufPtr[i + 1];
  45                         bufPtr[i + 1] = tmp;
  46                 }
  47         }
  48 }
  49
  50 BYTE Reader::readByte() {
  51         BYTE out;
  52         d_rider.read((char*)&out, 1);
  53         return out;
  54 }
  55
  56 INTEGER Reader::readInt() {
  57         INTEGER buf;
  58         char *bufPtr = (char*)&buf;
  59         d_rider.read(bufPtr, 4);
  60         if (isLittleEndian()) {
  61                 return buf;
  62         } else {
  63                 INTEGER out;
  64                 char *outPtr = (char *)&out;
  65                 outPtr[0] = bufPtr[3]; outPtr[1] = bufPtr[2]; outPtr[2] = bufPtr[1]; outPtr[3] = bufPtr[0];
  66                 return out;
  67         }
  68 }
  69
  70 void Reader::readSString(SHORTCHAR *out) {
  71         while (*out = readSChar()) {
  72                 ++out;
  73         }
  74 }
  75
  76 void Reader::turnIntoAlien(int cause) {
  77         assert(cause > 0);
  78         d_cancelled = true;
  79         d_cause = cause;
  80         d_readAlien = true;
  81 }
  82
  83 bool Reader::isCancelled() {
  84         return d_cancelled;
  85 }
  86
  87 INTEGER Reader::readVersion(INTEGER min, INTEGER max) {
  88         INTEGER version = readByte();
  89         if (version < min || version > max) {
  90                 turnIntoAlien(ALIENVERSION);
  91         }
  92         return version;
  93 }
  94
  95 Store* Reader::readStore() {
  96         SHORTCHAR kind = readSChar();
  97         if (kind == Store::NIL) {
  98                 std::cout << "NIL STORE" << std::endl;
  99                 return readNilStore();
 100         } else if (kind == Store::LINK) {
 101                 std::cout << "LINK STORE" << std::endl;
 102                 return readLinkStore();
 103         } else if (kind == Store::NEWLINK) {
 104                 std::cout << "NEWLINK STORE" << std::endl;
 105                 return readNewLinkStore();
 106         } else if (kind == Store::STORE) {
 107                 std::cout << "STORE STORE" << std::endl;
 108                 return readStoreOrElemStore(false);
 109         } else if (kind == Store::ELEM) {
 110                 std::cout << "ELEM STORE" << std::endl;
 111                 return readStoreOrElemStore(true);
 112         } else {
 113                 std::cout << std::hex << (unsigned int)kind << std::endl;
 114                 throw 20;
 115         }
 116 }
 117 //      PROCEDURE (VAR rd: Reader) ReadStore* (OUT x: Store), NEW;
 118 //              VAR a: Alien; t: Kernel.Type;
 119 //                      len, pos, pos1, id, comment, next, down, downPos, nextTypeId, nextElemId, nextStoreId: INTEGER;
 120 //                      kind: SHORTCHAR; path: TypePath; type: TypeName;
 121 //                      save: ReaderState;
 122 Store *Reader::readNilStore() {
 123         INTEGER comment = readInt();
 124         std::streamoff next = readInt();
 125         d_state->end = d_rider.tellg();
 126         if (next > 0 || (next == 0 && comment % 2 == 1)) {
 127                 d_state->next = d_state->end + next;
 128         } else {
 129                 d_state->next = 0;
 130         }
 131         return 0;
 132 }
 133 //              IF kind = nil THEN
 134 //                      rd.ReadInt(comment); rd.ReadInt(next);
 135 //                      rd.st.end := rd.Pos();
 136 //                      IF (next > 0) OR ((next = 0) & ODD(comment)) THEN rd.st.next := rd.st.end + next ELSE rd.st.next := 0 END;
 137 //                      x := NIL
 138 Store *Reader::readLinkStore() {
 139         return 0;
 140 }
 141 //              ELSIF kind = link THEN
 142 //                      rd.ReadInt(id); rd.ReadInt(comment); rd.ReadInt(next);
 143 //                      rd.st.end := rd.Pos();
 144 //                      IF (next > 0) OR ((next = 0) & ODD(comment)) THEN rd.st.next := rd.st.end + next ELSE rd.st.next := 0 END;
 145 //                      x := ThisStore(rd.eDict, id)
 146 Store *Reader::readNewLinkStore() {
 147         return 0;
 148 }
 149 //              ELSIF kind = newlink THEN
 150 //                      rd.ReadInt(id); rd.ReadInt(comment); rd.ReadInt(next);
 151 //                      rd.st.end := rd.Pos();
 152 //                      IF (next > 0) OR ((next = 0) & ODD(comment)) THEN rd.st.next := rd.st.end + next ELSE rd.st.next := 0 END;
 153 //                      x := ThisStore(rd.sDict, id)
 154
 155 Store *Reader::readStoreOrElemStore(bool isElem) {
 156         INTEGER id = isElem ? d_elemList.size() : d_storeList.size();
 157         TypePath path = readPath();
 158         std::cout << path.toString() << std::endl;
 159         const std::string &type = path[0];
 160         INTEGER comment = readInt();
 161         std::streampos pos1 = d_rider.tellg();
 162         std::streamoff next = readInt();
 163         std::streamoff down = readInt();
 164         std::streamoff len = readInt();
 165         std::streampos pos = d_rider.tellg();
 166         if (next > 0) {
 167                 d_state->next = pos1 + next + (std::streamoff)4;
 168         } else {
 169                 d_state->next = 0;
 170         }
 171         int downPos = 0;
 172         if (down > 0) {
 173                 downPos = pos1 + down + (std::streamoff)8;
 174         }
 175         d_state->end = pos + len;
 176         d_cause = 0;
 177         assert(len >= 0);
 178         if (next != 0) {
 179                 assert(d_state->next > pos1);
 180                 if (down != 0) {
 181                         assert(downPos < d_state->next);
 182                 }
 183         }
 184         if (down > 0) {
 185                 assert(downPos > pos1);
 186                 assert(downPos < d_state->end);
 187         }
 188
 189         const TypeProxyBase *t = TypeRegister::getInstance().get(type); // FIXME type lookup here
 190         Store *x = 0;
 191         if (t != 0) {
 192                 x = t->newInstance(id);
 193         } else {
 194                 d_cause = TYPENOTFOUND;
 195         }
 196
 197         if (x != 0) { // IF READING SUCCEEDS, INSERT MORE CHECKS HERE
 198                 if (true) { // samePath(x, path)
 199                         ReaderState *save = d_state;
 200                         d_state = new ReaderState();
 201                         x->internalize(*this);
 202                         delete d_state;
 203                         d_state = save;
 204
 205                         if (d_cause != 0) {
 206                                 x = 0;
 207                         }
 208                         assert(d_rider.tellg() == d_state->end);
 209                         assert(!d_rider.eof());
 210                 } else {
 211 //                                      rd.cause := inconsistentType; AlienTypeReport(rd.cause, type);
 212                         x = 0;
 213                 }
 214         }
 215
 216         if (x != 0) {
 217                 if (d_store == 0) {
 218                         d_store = x;
 219                 } else {
 220                         // join(d_store, x)
 221                         std::cout << "Man, should have written join(.,.)" << std::endl;
 222                 }
 223                 if (isElem) {
 224                         d_elemList.push_back(x);
 225                 } else {
 226                         d_storeList.push_back(x);
 227                 }
 228         } else {
 229                 d_rider.seekg(pos); // x->internalize() could have left us anywhere
 230                 assert(d_cause != 0);
 231                 Alien *alien = new Alien(id, path); //, d_cause); //,file
 232                 if (d_store == 0) {
 233                         d_store = alien;
 234                 } else {
 235                         // join(d_store, alien)
 236                         std::cout << "Man, should have written join(.,.)" << std::endl;
 237                 }
 238                 if (isElem) {
 239                         d_elemList.push_back(alien);
 240                 } else {
 241                         d_storeList.push_back(alien);
 242                 }
 243                 ReaderState *save = d_state;
 244                 d_state = new ReaderState();
 245                 internalizeAlien(alien, downPos, save->end);
 246                 delete d_state;
 247                 d_state = save;
 248                 assert(d_rider.tellg() == d_state->end);
 249
 250                 // we've just read the alien, so reset the state
 251                 d_cause = 0;
 252                 d_cancelled = false;
 253                 d_readAlien = true;
 254                 return alien;
 255         }
 256
 257         return x;
 258 }
 259
 260
 261 void Reader::internalizeAlien(Alien *alien, std::streampos down, std::streampos end) {
 262         std::streampos next = down != 0 ? down : end;
 263         while (d_rider.tellg() < end) {
 264                 if (d_rider.tellg() < next) { // for some reason, this means its a piece (unstructured)
 265                         std::cout << "Alien Piece" << std::endl;
 266                         size_t len = next - d_rider.tellg();
 267                         char *buf = new char[len];
 268                         d_rider.read(buf, len);
 269                         AlienComponent *comp = new AlienPiece(buf, len);
 270                         alien->getComponents().push_back(comp);
 271                 } else { // that means we've got a store
 272                         std::cout << "Alien Store" << std::endl;
 273                         d_rider.seekg(next);
 274                         AlienComponent *comp = new AlienPart(readStore());
 275                         alien->getComponents().push_back(comp);
 276                         next = d_state->next > 0 ? d_state->next : end;
 277                 }
 278         }
 279 }
 280
 281 std::string &Reader::fixTypeName(std::string &name) {
 282         size_t pos = name.size() - 4;
 283         if (pos > 0 && name.substr(pos, 4).compare("Desc") == 0) {
 284                 return name.replace(pos, 4, "^");
 285         }
 286         return name;
 287 }
 288
 289 TypePath Reader::readPath() {
 290         TypePath path;
 291         SHORTCHAR kind = readSChar();
 292         SHORTCHAR *buf = new SHORTCHAR[64]; // TypeName has a maximum of length 64 (including terminator).
 293         int i;
 294         for (i = 0; kind == Store::NEWEXT; ++i) {
 295                 readSString(buf);
 296                 std::string name(buf);
 297                 path.push_back(fixTypeName(name));
 298                 addPathComponent(i == 0, path[i]);
 299 //                      IF path[i] # elemTName THEN INC(i) END;
 300                 kind = readSChar();
 301         }
 302
 303         if (kind == Store::NEWBASE) {
 304                 readSString(buf);
 305                 std::string name(buf);
 306                 path.push_back(fixTypeName(name));
 307                 addPathComponent(i == 0, path[i]);
 308                 ++i;
 309         } else if (kind == Store::OLDTYPE) {
 310                 int id = readInt();
 311                 if (i > 0) {
 312                         d_typeList[d_typeList.size() - 1]->baseId = id;
 313                 }
 314                 while (id != -1) {
 315                         path.push_back(d_typeList[id]->name);
 316                         id = d_typeList[id]->baseId;
 317 //                              IF path[i] # elemTName THEN INC(i) END
 318                         ++i;
 319                 }
 320         } else {
 321                 throw 100;
 322         }
 323         return path;
 324 }
 325
 326 void Reader::addPathComponent(bool first, const std::string &typeName) {
 327         int next = d_typeList.size();
 328         int curr = next - 1;
 329         if (!first) {
 330                 d_typeList[curr]->baseId = next;
 331         }
 332         d_typeList.push_back(new TypeEntry(typeName));
 333 }
 334
 335 } // namespace odc