src/util/serialize.cpp

   1 /*
   2 Minetest
   3 Copyright (C) 2010-2013 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 "serialize.h"
  21 #include "pointer.h"
  22 #include "porting.h"
  23 #include "util/string.h"
  24 #include "../exceptions.h"
  25 #include "../irrlichttypes.h"
  26
  27 #include <sstream>
  28 #include <iomanip>
  29 #include <vector>
  30
  31 // Creates a string with the length as the first two bytes
  32 std::string serializeString(const std::string &plain)
  33 {
  34         //assert(plain.size() <= 65535);
  35         if(plain.size() > 65535)
  36                 throw SerializationError("String too long for serializeString");
  37         char buf[2];
  38         writeU16((u8*)&buf[0], plain.size());
  39         std::string s;
  40         s.append(buf, 2);
  41         s.append(plain);
  42         return s;
  43 }
  44
  45 // Creates a string with the length as the first two bytes from wide string
  46 std::string serializeWideString(const std::wstring &plain)
  47 {
  48         //assert(plain.size() <= 65535);
  49         if(plain.size() > 65535)
  50                 throw SerializationError("String too long for serializeString");
  51         char buf[2];
  52         writeU16((u8*)buf, plain.size());
  53         std::string s;
  54         s.append(buf, 2);
  55         for(u32 i=0; i<plain.size(); i++)
  56         {
  57                 writeU16((u8*)buf, plain[i]);
  58                 s.append(buf, 2);
  59         }
  60         return s;
  61 }
  62
  63 // Reads a string with the length as the first two bytes
  64 std::string deSerializeString(std::istream &is)
  65 {
  66         char buf[2];
  67         is.read(buf, 2);
  68         if(is.gcount() != 2)
  69                 throw SerializationError("deSerializeString: size not read");
  70         u16 s_size = readU16((u8*)buf);
  71         std::string s;
  72         if(s_size == 0)
  73                 return s;
  74         Buffer<char> buf2(s_size);
  75         is.read(&buf2[0], s_size);
  76         s.reserve(s_size);
  77         s.append(&buf2[0], s_size);
  78         return s;
  79 }
  80
  81 // Reads a wide string with the length as the first two bytes
  82 std::wstring deSerializeWideString(std::istream &is)
  83 {
  84         char buf[2];
  85         is.read(buf, 2);
  86         if(is.gcount() != 2)
  87                 throw SerializationError("deSerializeString: size not read");
  88         u16 s_size = readU16((u8*)buf);
  89         std::wstring s;
  90         if(s_size == 0)
  91                 return s;
  92         s.reserve(s_size);
  93         for(u32 i=0; i<s_size; i++)
  94         {
  95                 is.read(&buf[0], 2);
  96                 wchar_t c16 = readU16((u8*)buf);
  97                 s.append(&c16, 1);
  98         }
  99         return s;
 100 }
 101
 102 // Creates a string with the length as the first four bytes
 103 std::string serializeLongString(const std::string &plain)
 104 {
 105         char buf[4];
 106         writeU32((u8*)&buf[0], plain.size());
 107         std::string s;
 108         s.append(buf, 4);
 109         s.append(plain);
 110         return s;
 111 }
 112
 113 // Reads a string with the length as the first four bytes
 114 std::string deSerializeLongString(std::istream &is)
 115 {
 116         char buf[4];
 117         is.read(buf, 4);
 118         if(is.gcount() != 4)
 119                 throw SerializationError("deSerializeLongString: size not read");
 120         u32 s_size = readU32((u8*)buf);
 121         std::string s;
 122         if(s_size == 0)
 123                 return s;
 124         Buffer<char> buf2(s_size);
 125         is.read(&buf2[0], s_size);
 126         s.reserve(s_size);
 127         s.append(&buf2[0], s_size);
 128         return s;
 129 }
 130
 131 // Creates a string encoded in JSON format (almost equivalent to a C string literal)
 132 std::string serializeJsonString(const std::string &plain)
 133 {
 134         std::ostringstream os(std::ios::binary);
 135         os<<"\"";
 136         for(size_t i = 0; i < plain.size(); i++)
 137         {
 138                 char c = plain[i];
 139                 switch(c)
 140                 {
 141                         case '"': os<<"\\\""; break;
 142                         case '\\': os<<"\\\\"; break;
 143                         case '/': os<<"\\/"; break;
 144                         case '\b': os<<"\\b"; break;
 145                         case '\f': os<<"\\f"; break;
 146                         case '\n': os<<"\\n"; break;
 147                         case '\r': os<<"\\r"; break;
 148                         case '\t': os<<"\\t"; break;
 149                         default:
 150                         {
 151                                 if(c >= 32 && c <= 126)
 152                                 {
 153                                         os<<c;
 154                                 }
 155                                 else
 156                                 {
 157                                         u32 cnum = (u32) (u8) c;
 158                                         os<<"\\u"<<std::hex<<std::setw(4)<<std::setfill('0')<<cnum;
 159                                 }
 160                                 break;
 161                         }
 162                 }
 163         }
 164         os<<"\"";
 165         return os.str();
 166 }
 167
 168 // Reads a string encoded in JSON format
 169 std::string deSerializeJsonString(std::istream &is)
 170 {
 171         std::ostringstream os(std::ios::binary);
 172         char c, c2;
 173
 174         // Parse initial doublequote
 175         is >> c;
 176         if(c != '"')
 177                 throw SerializationError("JSON string must start with doublequote");
 178
 179         // Parse characters
 180         for(;;)
 181         {
 182                 c = is.get();
 183                 if(is.eof())
 184                         throw SerializationError("JSON string ended prematurely");
 185                 if(c == '"')
 186                 {
 187                         return os.str();
 188                 }
 189                 else if(c == '\\')
 190                 {
 191                         c2 = is.get();
 192                         if(is.eof())
 193                                 throw SerializationError("JSON string ended prematurely");
 194                         switch(c2)
 195                         {
 196                                 default:  os<<c2; break;
 197                                 case 'b': os<<'\b'; break;
 198                                 case 'f': os<<'\f'; break;
 199                                 case 'n': os<<'\n'; break;
 200                                 case 'r': os<<'\r'; break;
 201                                 case 't': os<<'\t'; break;
 202                                 case 'u':
 203                                 {
 204                                         char hexdigits[4+1];
 205                                         is.read(hexdigits, 4);
 206                                         if(is.eof())
 207                                                 throw SerializationError("JSON string ended prematurely");
 208                                         hexdigits[4] = 0;
 209                                         std::istringstream tmp_is(hexdigits, std::ios::binary);
 210                                         int hexnumber;
 211                                         tmp_is >> std::hex >> hexnumber;
 212                                         os<<((char)hexnumber);
 213                                         break;
 214                                 }
 215                         }
 216                 }
 217                 else
 218                 {
 219                         os<<c;
 220                 }
 221         }
 222         return os.str();
 223 }
 224
 225
 226 bool deSerializeStringToStruct(std::string valstr,
 227         std::string format, void *out, size_t olen)
 228 {
 229         size_t len = olen;
 230         std::vector<std::string *> strs_alloced;
 231         std::string *str;
 232         char *f, *snext;
 233         size_t pos;
 234
 235         char *s = &valstr[0];
 236         char *buf = new char[len];
 237         char *bufpos = buf;
 238
 239         char *fmtpos, *fmt = &format[0];
 240         while ((f = strtok_r(fmt, ",", &fmtpos)) && s) {
 241                 fmt = NULL;
 242
 243                 bool is_unsigned = false;
 244                 int width = 0;
 245                 char valtype = *f;
 246
 247                 width = (int)strtol(f + 1, &f, 10);
 248                 if (width && valtype == 's')
 249                         valtype = 'i';
 250
 251                 switch (valtype) {
 252                         case 'u':
 253                                 is_unsigned = true;
 254                                 /* FALLTHROUGH */
 255                         case 'i':
 256                                 if (width == 16) {
 257                                         bufpos += PADDING(bufpos, u16);
 258                                         if ((bufpos - buf) + sizeof(u16) <= len) {
 259                                                 if (is_unsigned)
 260                                                         *(u16 *)bufpos = (u16)strtoul(s, &s, 10);
 261                                                 else
 262                                                         *(s16 *)bufpos = (s16)strtol(s, &s, 10);
 263                                         }
 264                                         bufpos += sizeof(u16);
 265                                 } else if (width == 32) {
 266                                         bufpos += PADDING(bufpos, u32);
 267                                         if ((bufpos - buf) + sizeof(u32) <= len) {
 268                                                 if (is_unsigned)
 269                                                         *(u32 *)bufpos = (u32)strtoul(s, &s, 10);
 270                                                 else
 271                                                         *(s32 *)bufpos = (s32)strtol(s, &s, 10);
 272                                         }
 273                                         bufpos += sizeof(u32);
 274                                 } else if (width == 64) {
 275                                         bufpos += PADDING(bufpos, u64);
 276                                         if ((bufpos - buf) + sizeof(u64) <= len) {
 277                                                 if (is_unsigned)
 278                                                         *(u64 *)bufpos = (u64)strtoull(s, &s, 10);
 279                                                 else
 280                                                         *(s64 *)bufpos = (s64)strtoll(s, &s, 10);
 281                                         }
 282                                         bufpos += sizeof(u64);
 283                                 }
 284                                 s = strchr(s, ',');
 285                                 break;
 286                         case 'b':
 287                                 snext = strchr(s, ',');
 288                                 if (snext)
 289                                         *snext++ = 0;
 290
 291                                 bufpos += PADDING(bufpos, bool);
 292                                 if ((bufpos - buf) + sizeof(bool) <= len)
 293                                         *(bool *)bufpos = is_yes(std::string(s));
 294                                 bufpos += sizeof(bool);
 295
 296                                 s = snext;
 297                                 break;
 298                         case 'f':
 299                                 bufpos += PADDING(bufpos, float);
 300                                 if ((bufpos - buf) + sizeof(float) <= len)
 301                                         *(float *)bufpos = strtof(s, &s);
 302                                 bufpos += sizeof(float);
 303
 304                                 s = strchr(s, ',');
 305                                 break;
 306                         case 's':
 307                                 while (*s == ' ' || *s == '\t')
 308                                         s++;
 309                                 if (*s++ != '"') //error, expected string
 310                                         goto fail;
 311                                 snext = s;
 312
 313                                 while (snext[0] && !(snext[-1] != '\\' && snext[0] == '"'))
 314                                         snext++;
 315                                 *snext++ = 0;
 316
 317                                 bufpos += PADDING(bufpos, std::string *);
 318
 319                                 str = new std::string(s);
 320                                 pos = 0;
 321                                 while ((pos = str->find("\\\"", pos)) != std::string::npos)
 322                                         str->erase(pos, 1);
 323
 324                                 if ((bufpos - buf) + sizeof(std::string *) <= len)
 325                                         *(std::string **)bufpos = str;
 326                                 bufpos += sizeof(std::string *);
 327                                 strs_alloced.push_back(str);
 328
 329                                 s = *snext ? snext + 1 : NULL;
 330                                 break;
 331                         case 'v':
 332                                 while (*s == ' ' || *s == '\t')
 333                                         s++;
 334                                 if (*s++ != '(') //error, expected vector
 335                                         goto fail;
 336
 337                                 if (width == 2) {
 338                                         bufpos += PADDING(bufpos, v2f);
 339
 340                                         if ((bufpos - buf) + sizeof(v2f) <= len) {
 341                                         v2f *v = (v2f *)bufpos;
 342                                                 v->X = strtof(s, &s);
 343                                                 s++;
 344                                                 v->Y = strtof(s, &s);
 345                                         }
 346
 347                                         bufpos += sizeof(v2f);
 348                                 } else if (width == 3) {
 349                                         bufpos += PADDING(bufpos, v3f);
 350                                         if ((bufpos - buf) + sizeof(v3f) <= len) {
 351                                                 v3f *v = (v3f *)bufpos;
 352                                                 v->X = strtof(s, &s);
 353                                                 s++;
 354                                                 v->Y = strtof(s, &s);
 355                                                 s++;
 356                                                 v->Z = strtof(s, &s);
 357                                         }
 358
 359                                         bufpos += sizeof(v3f);
 360                                 }
 361                                 s = strchr(s, ',');
 362                                 break;
 363                         default: //error, invalid format specifier
 364                                 goto fail;
 365                 }
 366
 367                 if (s && *s == ',')
 368                         s++;
 369
 370                 if ((size_t)(bufpos - buf) > len) //error, buffer too small
 371                         goto fail;
 372         }
 373
 374         if (f && *f) { //error, mismatched number of fields and values
 375 fail:
 376                 for (size_t i = 0; i != strs_alloced.size(); i++)
 377                         delete strs_alloced[i];
 378                 delete[] buf;
 379                 return false;
 380         }
 381
 382         memcpy(out, buf, olen);
 383         delete[] buf;
 384         return true;
 385 }
 386
 387
 388 // Casts *buf to a signed or unsigned fixed-width integer of 'w' width
 389 #define SIGN_CAST(w, buf) (is_unsigned ? *((u##w *) buf) : *((s##w *) buf))
 390
 391 bool serializeStructToString(std::string *out,
 392         std::string format, void *value)
 393 {
 394         std::ostringstream os;
 395         std::string str;
 396         char *f;
 397         size_t strpos;
 398
 399         char *bufpos = (char *) value;
 400         char *fmtpos, *fmt = &format[0];
 401         while ((f = strtok_r(fmt, ",", &fmtpos))) {
 402                 fmt = NULL;
 403                 bool is_unsigned = false;
 404                 int width = 0;
 405                 char valtype = *f;
 406
 407                 width = (int)strtol(f + 1, &f, 10);
 408                 if (width && valtype == 's')
 409                         valtype = 'i';
 410
 411                 switch (valtype) {
 412                         case 'u':
 413                                 is_unsigned = true;
 414                                 /* FALLTHROUGH */
 415                         case 'i':
 416                                 if (width == 16) {
 417                                         bufpos += PADDING(bufpos, u16);
 418                                         os << SIGN_CAST(16, bufpos);
 419                                         bufpos += sizeof(u16);
 420                                 } else if (width == 32) {
 421                                         bufpos += PADDING(bufpos, u32);
 422                                         os << SIGN_CAST(32, bufpos);
 423                                         bufpos += sizeof(u32);
 424                                 } else if (width == 64) {
 425                                         bufpos += PADDING(bufpos, u64);
 426                                         os << SIGN_CAST(64, bufpos);
 427                                         bufpos += sizeof(u64);
 428                                 }
 429                                 break;
 430                         case 'b':
 431                                 bufpos += PADDING(bufpos, bool);
 432                                 os << std::boolalpha << *((bool *) bufpos);
 433                                 bufpos += sizeof(bool);
 434                                 break;
 435                         case 'f':
 436                                 bufpos += PADDING(bufpos, float);
 437                                 os << *((float *) bufpos);
 438                                 bufpos += sizeof(float);
 439                                 break;
 440                         case 's':
 441                                 bufpos += PADDING(bufpos, std::string *);
 442                                 str = **((std::string **) bufpos);
 443
 444                                 strpos = 0;
 445                                 while ((strpos = str.find('"', strpos)) != std::string::npos) {
 446                                         str.insert(strpos, 1, '\\');
 447                                         strpos += 2;
 448                                 }
 449
 450                                 os << str;
 451                                 bufpos += sizeof(std::string *);
 452                                 break;
 453                         case 'v':
 454                                 if (width == 2) {
 455                                         bufpos += PADDING(bufpos, v2f);
 456                                         v2f *v = (v2f *) bufpos;
 457                                         os << '(' << v->X << ", " << v->Y << ')';
 458                                         bufpos += sizeof(v2f);
 459                                 } else {
 460                                         bufpos += PADDING(bufpos, v3f);
 461                                         v3f *v = (v3f *) bufpos;
 462                                         os << '(' << v->X << ", " << v->Y << ", " << v->Z << ')';
 463                                         bufpos += sizeof(v3f);
 464                                 }
 465                                 break;
 466                         default:
 467                                 return false;
 468                 }
 469                 os << ", ";
 470         }
 471         *out = os.str();
 472
 473         // Trim off the trailing comma and space
 474         if (out->size() >= 2) {
 475                 out->resize(out->size() - 2);
 476         }
 477
 478         return true;
 479 }
 480
 481 #undef SIGN_CAST