1 // 2 // C++ Implementation: GUIDData 3 // 4 // Description: GUIDData class header 5 // Implements the GUIDData data structure and support methods 6 // 7 // 8 // Author: Rod Smith <rodsmith (at) rodsbooks.com>, (C) 2010-2011 9 // 10 // Copyright: See COPYING file that comes with this distribution 11 // 12 // 13 14 #define __STDC_LIMIT_MACROS 15 #define __STDC_CONSTANT_MACROS 16 17 #include <stdio.h> 18 #include <time.h> 19 #include <string.h> 20 #include <string> 21 #include <iostream> 22 #include "guid.h" 23 #include "support.h" 24 25 using namespace std; 26 27 bool GUIDData::firstInstance = 1; 28 29 GUIDData::GUIDData(void) { 30 if (firstInstance) { 31 srand((unsigned int) time(0)); 32 firstInstance = 0; 33 } // if 34 Zero(); 35 } // constructor 36 37 GUIDData::GUIDData(const GUIDData & orig) { 38 memcpy(uuidData, orig.uuidData, sizeof(uuidData)); 39 } // copy constructor 40 41 GUIDData::GUIDData(const string & orig) { 42 operator=(orig); 43 } // copy (from string) constructor 44 45 GUIDData::GUIDData(const char * orig) { 46 operator=(orig); 47 } // copy (from char*) constructor 48 49 GUIDData::~GUIDData(void) { 50 } // destructor 51 52 GUIDData & GUIDData::operator=(const GUIDData & orig) { 53 memcpy(uuidData, orig.uuidData, sizeof(uuidData)); 54 return *this; 55 } // GUIDData::operator=(const GUIDData & orig) 56 57 // Assign the GUID from a string input value. A GUID is normally formatted 58 // with four dashes as element separators, for a total length of 36 59 // characters. If the input string is this long or longer, this function 60 // assumes standard separator positioning; if the input string is less 61 // than 36 characters long, this function assumes the input GUID has 62 // been compressed by removal of separators. In either event, there's 63 // little in the way of sanity checking, so garbage in = garbage out! 64 // One special case: If the first character is 'r' or 'R', a random 65 // GUID is assigned. 66 GUIDData & GUIDData::operator=(const string & orig) { 67 string copy, fragment; 68 size_t len; 69 // Break points for segments, either with or without characters separating the segments.... 70 size_t longSegs[6] = {0, 9, 14, 19, 24, 36}; 71 size_t shortSegs[6] = {0, 8, 12, 16, 20, 32}; 72 size_t *segStart = longSegs; // Assume there are separators between segments 73 74 // If first character is an 'R' or 'r', set a random GUID; otherwise, 75 // try to parse it as a real GUID 76 if ((orig[0] == 'R') || (orig[0] == 'r')) { 77 Randomize(); 78 } else { 79 Zero(); 80 81 // Delete stray spaces.... 82 copy = DeleteSpaces(orig); 83 84 // If length is too short, assume there are no separators between segments 85 len = copy.length(); 86 if (len < 36) { 87 segStart = shortSegs; 88 }; 89 90 // Extract data fragments at fixed locations and convert to 91 // integral types.... 92 if (len >= segStart[1]) { 93 uuidData[3] = StrToHex(copy, 0); 94 uuidData[2] = StrToHex(copy, 2); 95 uuidData[1] = StrToHex(copy, 4); 96 uuidData[0] = StrToHex(copy, 6); 97 } // if 98 if (len >= segStart[2]) { 99 uuidData[5] = StrToHex(copy, (unsigned int) segStart[1]); 100 uuidData[4] = StrToHex(copy, (unsigned int) segStart[1] + 2); 101 } // if 102 if (len >= segStart[3]) { 103 uuidData[7] = StrToHex(copy, (unsigned int) segStart[2]); 104 uuidData[6] = StrToHex(copy, (unsigned int) segStart[2] + 2); 105 } // if 106 if (len >= segStart[4]) { 107 uuidData[8] = StrToHex(copy, (unsigned int) segStart[3]); 108 uuidData[9] = StrToHex(copy, (unsigned int) segStart[3] + 2); 109 } // if 110 if (len >= segStart[5]) { 111 uuidData[10] = StrToHex(copy, (unsigned int) segStart[4]); 112 uuidData[11] = StrToHex(copy, (unsigned int) segStart[4] + 2); 113 uuidData[12] = StrToHex(copy, (unsigned int) segStart[4] + 4); 114 uuidData[13] = StrToHex(copy, (unsigned int) segStart[4] + 6); 115 uuidData[14] = StrToHex(copy, (unsigned int) segStart[4] + 8); 116 uuidData[15] = StrToHex(copy, (unsigned int) segStart[4] + 10); 117 } // if 118 } // if/else randomize/set value 119 120 return *this; 121 } // GUIDData::operator=(const string & orig) 122 123 // Assignment from C-style string; rely on C++ casting.... 124 GUIDData & GUIDData::operator=(const char * orig) { 125 return operator=((string) orig); 126 } // GUIDData::operator=(const char * orig) 127 128 // Erase the contents of the GUID 129 void GUIDData::Zero(void) { 130 memset(uuidData, 0, sizeof(uuidData)); 131 } // GUIDData::Zero() 132 133 // Set a completely random GUID value.... 134 // The uuid_generate() function returns a value that needs to have its 135 // first three fields byte-reversed to conform to Intel's GUID layout. 136 // The Windows UuidCreate() function doesn't need this adjustment. If 137 // neither function is defined, or if UuidCreate() fails, set a completely 138 // random GUID -- not completely kosher, but it works on most platforms 139 // (immediately after creating the UUID on Windows 7 being an important 140 // exception). 141 void GUIDData::Randomize(void) { 142 int i, uuidGenerated = 0; 143 144 #ifdef _UUID_UUID_H 145 uuid_generate(uuidData); 146 ReverseBytes(&uuidData[0], 4); 147 ReverseBytes(&uuidData[4], 2); 148 ReverseBytes(&uuidData[6], 2); 149 uuidGenerated = 1; 150 #endif 151 #if defined (_RPC_H) || defined (__RPC_H__) 152 UUID MsUuid; 153 if (UuidCreate(&MsUuid) == RPC_S_OK) { 154 memcpy(uuidData, &MsUuid, 16); 155 uuidGenerated = 1; 156 } // if 157 #endif 158 159 if (!uuidGenerated) { 160 cerr << "Warning! Unable to generate a proper UUID! Creating an improper one as a last\n" 161 << "resort! Windows 7 may crash if you save this partition table!\a\n"; 162 for (i = 0; i < 16; i++) 163 uuidData[i] = (unsigned char) (256.0 * (rand() / (RAND_MAX + 1.0))); 164 } // if 165 } // GUIDData::Randomize 166 167 // Equality operator; returns 1 if the GUIDs are equal, 0 if they're unequal 168 int GUIDData::operator==(const GUIDData & orig) const { 169 return !memcmp(uuidData, orig.uuidData, sizeof(uuidData)); 170 } // GUIDData::operator== 171 172 // Inequality operator; returns 1 if the GUIDs are unequal, 0 if they're equal 173 int GUIDData::operator!=(const GUIDData & orig) const { 174 return !operator==(orig); 175 } // GUIDData::operator!= 176 177 // Return the GUID as a string, suitable for display to the user. 178 string GUIDData::AsString(void) const { 179 char theString[40]; 180 181 sprintf(theString, 182 "%02X%02X%02X%02X-%02X%02X-%02X%02X-%02X%02X-%02X%02X%02X%02X%02X%02X", 183 uuidData[3], uuidData[2], uuidData[1], uuidData[0], uuidData[5], 184 uuidData[4], uuidData[7], uuidData[6], uuidData[8], uuidData[9], 185 uuidData[10], uuidData[11], uuidData[12], uuidData[13], uuidData[14], 186 uuidData[15]); 187 return theString; 188 } // GUIDData::AsString(void) 189 190 // Delete spaces or braces (which often enclose GUIDs) from the orig string, 191 // returning modified string. 192 string GUIDData::DeleteSpaces(string s) { 193 size_t position; 194 195 if (s.length() > 0) { 196 for (position = s.length(); position > 0; position--) { 197 if ((s[position - 1] == ' ') || (s[position - 1] == '{') || (s[position - 1] == '}')) { 198 s.erase(position - 1, 1); 199 } // if 200 } // for 201 } // if 202 return s; 203 } // GUIDData::DeleteSpaces() 204 205 /******************************* 206 * * 207 * Non-class support functions * 208 * * 209 *******************************/ 210 211 // Display a GUID as a string.... 212 ostream & operator<<(ostream & os, const GUIDData & data) { 213 // string asString; 214 215 os << data.AsString(); 216 return os; 217 } // GUIDData::operator<<() 218
