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 FloatType g_serialize_f32_type = FLOATTYPE_UNKNOWN;
  32
  33
  34 ////
  35 //// String
  36 ////
  37
  38 std::string serializeString16(const std::string &plain)
  39 {
  40         std::string s;
  41         char buf[2];
  42
  43         if (plain.size() > STRING_MAX_LEN)
  44                 throw SerializationError("String too long for serializeString16");
  45         s.reserve(2 + plain.size());
  46
  47         writeU16((u8 *)&buf[0], plain.size());
  48         s.append(buf, 2);
  49
  50         s.append(plain);
  51         return s;
  52 }
  53
  54 std::string deSerializeString16(std::istream &is)
  55 {
  56         std::string s;
  57         char buf[2];
  58
  59         is.read(buf, 2);
  60         if (is.gcount() != 2)
  61                 throw SerializationError("deSerializeString16: size not read");
  62
  63         u16 s_size = readU16((u8 *)buf);
  64         if (s_size == 0)
  65                 return s;
  66
  67         s.resize(s_size);
  68         is.read(&s[0], s_size);
  69         if (is.gcount() != s_size)
  70                 throw SerializationError("deSerializeString16: couldn't read all chars");
  71
  72         return s;
  73 }
  74
  75
  76 ////
  77 //// Long String
  78 ////
  79
  80 std::string serializeString32(const std::string &plain)
  81 {
  82         std::string s;
  83         char buf[4];
  84
  85         if (plain.size() > LONG_STRING_MAX_LEN)
  86                 throw SerializationError("String too long for serializeLongString");
  87         s.reserve(4 + plain.size());
  88
  89         writeU32((u8*)&buf[0], plain.size());
  90         s.append(buf, 4);
  91         s.append(plain);
  92         return s;
  93 }
  94
  95 std::string deSerializeString32(std::istream &is)
  96 {
  97         std::string s;
  98         char buf[4];
  99
 100         is.read(buf, 4);
 101         if (is.gcount() != 4)
 102                 throw SerializationError("deSerializeLongString: size not read");
 103
 104         u32 s_size = readU32((u8 *)buf);
 105         if (s_size == 0)
 106                 return s;
 107
 108         // We don't really want a remote attacker to force us to allocate 4GB...
 109         if (s_size > LONG_STRING_MAX_LEN) {
 110                 throw SerializationError("deSerializeLongString: "
 111                         "string too long: " + itos(s_size) + " bytes");
 112         }
 113
 114         s.resize(s_size);
 115         is.read(&s[0], s_size);
 116         if ((u32)is.gcount() != s_size)
 117                 throw SerializationError("deSerializeLongString: couldn't read all chars");
 118
 119         return s;
 120 }
 121
 122 ////
 123 //// JSON
 124 ////
 125
 126 std::string serializeJsonString(const std::string &plain)
 127 {
 128         std::ostringstream os(std::ios::binary);
 129         os << "\"";
 130
 131         for (char c : plain) {
 132                 switch (c) {
 133                         case '"':
 134                                 os << "\\\"";
 135                                 break;
 136                         case '\\':
 137                                 os << "\\\\";
 138                                 break;
 139                         case '/':
 140                                 os << "\\/";
 141                                 break;
 142                         case '\b':
 143                                 os << "\\b";
 144                                 break;
 145                         case '\f':
 146                                 os << "\\f";
 147                                 break;
 148                         case '\n':
 149                                 os << "\\n";
 150                                 break;
 151                         case '\r':
 152                                 os << "\\r";
 153                                 break;
 154                         case '\t':
 155                                 os << "\\t";
 156                                 break;
 157                         default: {
 158                                 if (c >= 32 && c <= 126) {
 159                                         os << c;
 160                                 } else {
 161                                         u32 cnum = (u8)c;
 162                                         os << "\\u" << std::hex << std::setw(4)
 163                                                 << std::setfill('0') << cnum;
 164                                 }
 165                                 break;
 166                         }
 167                 }
 168         }
 169
 170         os << "\"";
 171         return os.str();
 172 }
 173
 174 std::string deSerializeJsonString(std::istream &is)
 175 {
 176         std::ostringstream os(std::ios::binary);
 177         char c, c2;
 178
 179         // Parse initial doublequote
 180         is >> c;
 181         if (c != '"')
 182                 throw SerializationError("JSON string must start with doublequote");
 183
 184         // Parse characters
 185         for (;;) {
 186                 c = is.get();
 187                 if (is.eof())
 188                         throw SerializationError("JSON string ended prematurely");
 189
 190                 if (c == '"') {
 191                         return os.str();
 192                 }
 193
 194                 if (c == '\\') {
 195                         c2 = is.get();
 196                         if (is.eof())
 197                                 throw SerializationError("JSON string ended prematurely");
 198                         switch (c2) {
 199                                 case 'b':
 200                                         os << '\b';
 201                                         break;
 202                                 case 'f':
 203                                         os << '\f';
 204                                         break;
 205                                 case 'n':
 206                                         os << '\n';
 207                                         break;
 208                                 case 'r':
 209                                         os << '\r';
 210                                         break;
 211                                 case 't':
 212                                         os << '\t';
 213                                         break;
 214                                 case 'u': {
 215                                         int hexnumber;
 216                                         char hexdigits[4 + 1];
 217
 218                                         is.read(hexdigits, 4);
 219                                         if (is.eof())
 220                                                 throw SerializationError("JSON string ended prematurely");
 221                                         hexdigits[4] = 0;
 222
 223                                         std::istringstream tmp_is(hexdigits, std::ios::binary);
 224                                         tmp_is >> std::hex >> hexnumber;
 225                                         os << (char)hexnumber;
 226                                         break;
 227                                 }
 228                                 default:
 229                                         os << c2;
 230                                         break;
 231                         }
 232                 } else {
 233                         os << c;
 234                 }
 235         }
 236
 237         return os.str();
 238 }
 239
 240 std::string serializeJsonStringIfNeeded(const std::string &s)
 241 {
 242         for (size_t i = 0; i < s.size(); ++i) {
 243                 if (s[i] <= 0x1f || s[i] >= 0x7f || s[i] == ' ' || s[i] == '\"')
 244                         return serializeJsonString(s);
 245         }
 246         return s;
 247 }
 248
 249 std::string deSerializeJsonStringIfNeeded(std::istream &is)
 250 {
 251         std::stringstream tmp_os(std::ios_base::binary | std::ios_base::in | std::ios_base::out);
 252         bool expect_initial_quote = true;
 253         bool is_json = false;
 254         bool was_backslash = false;
 255         for (;;) {
 256                 char c = is.get();
 257                 if (is.eof())
 258                         break;
 259
 260                 if (expect_initial_quote && c == '"') {
 261                         tmp_os << c;
 262                         is_json = true;
 263                 } else if(is_json) {
 264                         tmp_os << c;
 265                         if (was_backslash)
 266                                 was_backslash = false;
 267                         else if (c == '\\')
 268                                 was_backslash = true;
 269                         else if (c == '"')
 270                                 break; // Found end of string
 271                 } else {
 272                         if (c == ' ') {
 273                                 // Found end of word
 274                                 is.unget();
 275                                 break;
 276                         }
 277
 278                         tmp_os << c;
 279                 }
 280                 expect_initial_quote = false;
 281         }
 282         if (is_json) {
 283                 return deSerializeJsonString(tmp_os);
 284         }
 285
 286         return tmp_os.str();
 287 }
 288