Disk ARchive 2.3.10
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00001 /*********************************************************************/ 00002 // dar - disk archive - a backup/restoration program 00003 // Copyright (C) 2002-2052 Denis Corbin 00004 // 00005 // This program is free software; you can redistribute it and/or 00006 // modify it under the terms of the GNU General Public License 00007 // as published by the Free Software Foundation; either version 2 00008 // of the License, or (at your option) any later version. 00009 // 00010 // This program is distributed in the hope that it will be useful, 00011 // but WITHOUT ANY WARRANTY; without even the implied warranty of 00012 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 00013 // GNU General Public License for more details. 00014 // 00015 // You should have received a copy of the GNU General Public License 00016 // along with this program; if not, write to the Free Software 00017 // Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. 00018 // 00019 // to contact the author : dar.linux@free.fr 00020 /*********************************************************************/ 00021 // $Id: real_infinint.hpp,v 1.14.2.2 2007/07/22 16:35:00 edrusb Rel $ 00022 // 00023 /*********************************************************************/ 00024 00030 00031 #ifndef REAL_INFININT_HPP 00032 #define REAL_INFININT_HPP 00033 00034 #include "../my_config.h" 00035 00036 extern "C" 00037 { 00038 #if HAVE_SYS_TYPES_H 00039 #include <sys/types.h> 00040 #endif 00041 } // end extern "C" 00042 00043 #include <typeinfo> 00044 #include "storage.hpp" 00045 #include "integers.hpp" 00046 #include "int_tools.hpp" 00047 00048 namespace libdar 00049 { 00050 class generic_file; 00051 class user_interaction; 00052 00054 00057 class infinint 00058 { 00059 public : 00060 00061 #if SIZEOF_OFF_T > SIZEOF_TIME_T 00062 #if SIZEOF_OFF_T > SIZEOF_SIZE_T 00063 infinint(off_t a = 0) 00064 { E_BEGIN infinint_from(a); E_END("infinint::infinint", "off_t") }; 00065 #else 00066 infinint(size_t a = 0) 00067 { E_BEGIN infinint_from(a); E_END("infinint::infinint", "size_t") }; 00068 #endif 00069 #else 00070 #if SIZEOF_TIME_T > SIZEOF_SIZE_T 00071 infinint(time_t a = 0) 00072 { E_BEGIN infinint_from(a); E_END("infinint::infinint", "time_t") }; 00073 #else 00074 infinint(size_t a = 0) 00075 { E_BEGIN infinint_from(a); E_END("infinint::infinint", "size_t") }; 00076 #endif 00077 #endif 00078 00079 infinint(const infinint & ref) 00080 { E_BEGIN; copy_from(ref); E_END("infinint::infinint", "const infinint &"); } 00081 infinint(user_interaction & dialog, S_I *fd, generic_file *x); // read an infinint from a file 00082 ~infinint() 00083 { E_BEGIN detruit(); E_END("infinint::~infinint","") }; 00084 00085 infinint & operator = (const infinint & ref) 00086 { E_BEGIN detruit(); copy_from(ref); return *this; E_END("infinint::operator =","") }; 00087 00088 void dump(user_interaction & dialog, int fd) const; // write byte sequence to file 00089 void dump(generic_file &x) const; // write byte sequence to file 00090 void read(generic_file &f) { detruit(); build_from_file(f); }; 00091 00092 infinint & operator += (const infinint & ref); 00093 infinint & operator -= (const infinint & ref); 00094 infinint & operator *= (unsigned char arg); 00095 infinint & operator *= (const infinint & ref); 00096 template <class T> infinint power(const T & exponent) const; 00097 inline infinint & operator /= (const infinint & ref); 00098 inline infinint & operator %= (const infinint & ref); 00099 infinint & operator &= (const infinint & ref); 00100 infinint & operator |= (const infinint & ref); 00101 infinint & operator ^= (const infinint & ref); 00102 infinint & operator >>= (U_32 bit); 00103 infinint & operator >>= (infinint bit); 00104 infinint & operator <<= (U_32 bit); 00105 infinint & operator <<= (infinint bit); 00106 infinint operator ++(int a) 00107 { E_BEGIN infinint ret = *this; ++(*this); return ret; E_END("infinint::operator ++", "int") }; 00108 infinint operator --(int a) 00109 { E_BEGIN infinint ret = *this; --(*this); return ret; E_END("infinint::operator --", "int") }; 00110 infinint & operator ++() 00111 { E_BEGIN return *this += 1; E_END("infinint::operator ++", "()") }; 00112 infinint & operator --() 00113 { E_BEGIN return *this -= 1; E_END("infinint::operator --", "()") }; 00114 00115 U_32 operator % (U_32 arg) const 00116 { E_BEGIN return modulo(arg); E_END("infinint::operator %","") }; 00117 00118 // increment the argument up to a legal value for its storage type and decrement the object in consequence 00119 // note that the initial value of the argument is not ignored ! 00120 // when the object is null the value of the argument stays the same as before 00121 template <class T>void unstack(T &v) 00122 { E_BEGIN infinint_unstack_to(v); E_END("infinint::unstack", typeid(v).name()) } 00123 00124 infinint get_storage_size() const { return field->size(); }; 00125 // it returns number of byte of information necessary to store the integer 00126 00127 unsigned char operator [] (const infinint & position) const; 00128 // return in big endian order the information byte storing the integer 00129 00130 friend bool operator < (const infinint &, const infinint &); 00131 friend bool operator == (const infinint &, const infinint &); 00132 friend bool operator > (const infinint &, const infinint &); 00133 friend bool operator <= (const infinint &, const infinint &); 00134 friend bool operator != (const infinint &, const infinint &); 00135 friend bool operator >= (const infinint &, const infinint &); 00136 friend void euclide(infinint a, const infinint &b, infinint &q, infinint &r); 00137 00138 private : 00139 static const int TG = 4; 00140 00141 enum endian { big_endian, little_endian, not_initialized }; 00142 typedef unsigned char group[TG]; 00143 00144 storage *field; 00145 00146 bool is_valid() const; 00147 void build_from_file(generic_file & x); 00148 void reduce(); // put the object in canonical form : no leading byte equal to zero 00149 void copy_from(const infinint & ref); 00150 void detruit(); 00151 void make_at_least_as_wider_as(const infinint & ref); 00152 template <class T> void infinint_from(T a); 00153 template <class T> void infinint_unstack_to(T &a); 00154 template <class T> T modulo(T arg) const; 00155 signed int difference(const infinint & b) const; // gives the sign of (*this - arg) but only the sign ! 00156 00158 // static statments 00159 // 00160 static endian used_endian; 00161 static void setup_endian(); 00162 }; 00163 00164 00165 #define OPERATOR(OP) inline bool operator OP (const infinint &a, const infinint &b) \ 00166 { \ 00167 E_BEGIN \ 00168 return a.difference(b) OP 0; \ 00169 E_END("operator OP", "infinint, infinint") \ 00170 } 00171 00172 OPERATOR(<) 00173 OPERATOR(>) 00174 OPERATOR(<=) 00175 OPERATOR(>=) 00176 OPERATOR(==) 00177 OPERATOR(!=) 00178 00179 infinint operator + (const infinint &, const infinint &); 00180 infinint operator - (const infinint &, const infinint &); 00181 infinint operator * (const infinint &, const infinint &); 00182 infinint operator * (const infinint &, const unsigned char); 00183 infinint operator * (const unsigned char, const infinint &); 00184 infinint operator / (const infinint &, const infinint &); 00185 infinint operator % (const infinint &, const infinint &); 00186 infinint operator & (const infinint & a, const infinint & bit); 00187 infinint operator | (const infinint & a, const infinint & bit); 00188 infinint operator ^ (const infinint & a, const infinint & bit); 00189 infinint operator >> (const infinint & a, U_32 bit); 00190 infinint operator >> (const infinint & a, const infinint & bit); 00191 infinint operator << (const infinint & a, U_32 bit); 00192 infinint operator << (const infinint & a, const infinint & bit); 00193 void euclide(infinint a, const infinint &b, infinint &q, infinint &r); 00194 template <class T> inline void euclide(T a, T b, T & q, T &r) 00195 { 00196 E_BEGIN 00197 q = a/b; r = a%b; 00198 E_END("euclide", "") 00199 } 00200 00201 inline infinint & infinint::operator /= (const infinint & ref) 00202 { 00203 E_BEGIN 00204 *this = *this / ref; 00205 return *this; 00206 E_END("infinint::operator /=", "") 00207 } 00208 00209 inline infinint & infinint::operator %= (const infinint & ref) 00210 { 00211 E_BEGIN 00212 *this = *this % ref; 00213 return *this; 00214 E_END("infinint::operator %=", "") 00215 } 00216 00217 00221 00222 template <class T> infinint infinint::power(const T & exponent) const 00223 { 00224 infinint ret = 1; 00225 for(T count = 0; count < exponent; ++count) 00226 ret *= *this; 00227 00228 return ret; 00229 } 00230 00231 template <class T> T infinint::modulo(T arg) const 00232 { 00233 E_BEGIN 00234 infinint tmp = *this % infinint(arg); 00235 T ret = 0; 00236 unsigned char *debut = (unsigned char *)(&ret); 00237 unsigned char *ptr = debut + sizeof(T) - 1; 00238 storage::iterator it = tmp.field->rbegin(); 00239 00240 while(it != tmp.field->rend() && ptr >= debut) 00241 { 00242 *ptr = *it; 00243 --ptr; 00244 --it; 00245 } 00246 00247 if(it != tmp.field->rend()) 00248 throw SRC_BUG; // could not put all the data in the returned value ! 00249 00250 if(used_endian == big_endian) 00251 int_tools_swap_bytes(debut, sizeof(T)); 00252 00253 return ret; 00254 E_END("infinint::modulo", "") 00255 } 00256 00257 00258 template <class T> void infinint::infinint_from(T a) 00259 { 00260 E_BEGIN 00261 U_I size = sizeof(a); 00262 S_I direction = +1; 00263 unsigned char *ptr, *fin; 00264 00265 if(used_endian == not_initialized) 00266 setup_endian(); 00267 00268 if(used_endian == big_endian) 00269 { 00270 direction = -1; 00271 ptr = (unsigned char *)(&a) + (size - 1); 00272 fin = (unsigned char *)(&a) - 1; 00273 } 00274 else 00275 { 00276 direction = +1; 00277 ptr = (unsigned char *)(&a); 00278 fin = (unsigned char *)(&a) + size; 00279 } 00280 00281 while(ptr != fin && *ptr == 0) 00282 { 00283 ptr += direction; 00284 --size; 00285 } 00286 00287 if(size == 0) 00288 { 00289 size = 1; 00290 ptr -= direction; 00291 } 00292 00293 field = new storage(size); 00294 if(field != NULL) 00295 { 00296 storage::iterator it = field->begin(); 00297 00298 while(ptr != fin) 00299 { 00300 *it = *ptr; 00301 ++it; 00302 ptr += direction; 00303 } 00304 if(it != field->end()) 00305 throw SRC_BUG; // size mismatch in this algorithm 00306 } 00307 else 00308 throw Ememory("template infinint::infinint_from"); 00309 00310 E_END("infinint::infinint_from", "") 00311 } 00312 00313 template <class T> void infinint::infinint_unstack_to(T &a) 00314 { 00315 E_BEGIN 00316 // T is supposed to be an unsigned "integer" 00317 // (ie.: sizeof() returns the width of the storage bit field and no sign bit is present) 00318 // Note : static here avoids the recalculation of max_T at each call 00319 static const T max_T = int_tools_maxof_agregate(T(0)); 00320 infinint step = max_T - a; 00321 00322 if(*this < step) 00323 { 00324 T transfert = 0; 00325 unsigned char *debut = (unsigned char *)&transfert; 00326 unsigned char *ptr = debut + sizeof(transfert) - 1; 00327 storage::iterator it = field->rbegin(); 00328 00329 while(ptr >= debut && it != field->rend()) 00330 { 00331 *ptr = *it; 00332 --ptr; 00333 --it; 00334 } 00335 if(used_endian == big_endian) 00336 int_tools_swap_bytes(debut, sizeof(transfert)); 00337 a += transfert; 00338 *this -= *this; 00339 } 00340 else 00341 { 00342 *this -= step; 00343 a = max_T; 00344 } 00345 E_END("infinint::infinint_unstack_to", "") 00346 } 00347 00348 } // end of namespace 00349 00350 #endif