git.zerfleddert.de Git - proxmark3-svn/blob - client/util.c

   1 //-----------------------------------------------------------------------------
   2 // Copyright (C) 2010 iZsh <izsh at fail0verflow.com>
   3 //
   4 // This code is licensed to you under the terms of the GNU GPL, version 2 or,
   5 // at your option, any later version. See the LICENSE.txt file for the text of
   6 // the license.
   7 //-----------------------------------------------------------------------------
   8 // utilities
   9 //-----------------------------------------------------------------------------
  10
  11 #include "util.h"
  12
  13 #include <stdint.h>
  14 #include <string.h>
  15 #include <ctype.h>
  16 #include <stdlib.h>
  17 #include <stdio.h>
  18 #include <time.h>
  19
  20 #ifdef _WIN32
  21 #include <windows.h>
  22 #endif
  23
  24 #define MAX_BIN_BREAK_LENGTH   (3072+384+1)
  25
  26 #ifndef _WIN32
  27 #include <termios.h>
  28 #include <sys/ioctl.h>
  29 #include <unistd.h>
  30
  31 int ukbhit(void)
  32 {
  33   int cnt = 0;
  34   int error;
  35   static struct termios Otty, Ntty;
  36
  37   if ( tcgetattr(STDIN_FILENO, &Otty) == -1 ) return -1;
  38   Ntty = Otty;
  39
  40   Ntty.c_iflag          = 0x0000;   // input mode
  41   Ntty.c_oflag          = 0x0000;   // output mode
  42   Ntty.c_lflag         &= ~ICANON;  // control mode = raw
  43   Ntty.c_cc[VMIN]       = 1;        // return if at least 1 character is in the queue
  44   Ntty.c_cc[VTIME]      = 0;        // no timeout. Wait forever
  45
  46   if (0 == (error = tcsetattr(STDIN_FILENO, TCSANOW, &Ntty))) {   // set new attributes
  47     error += ioctl(STDIN_FILENO, FIONREAD, &cnt);                 // get number of characters availabe
  48     error += tcsetattr(STDIN_FILENO, TCSANOW, &Otty);             // reset attributes
  49   }
  50
  51   return ( error == 0 ? cnt : -1 );
  52 }
  53
  54 #else
  55
  56 #include <conio.h>
  57 int ukbhit(void) {
  58         return kbhit();
  59 }
  60 #endif
  61
  62 // log files functions
  63 void AddLogLine(char *file, char *extData, char *c) {
  64         FILE *fLog = NULL;
  65     char filename[FILE_PATH_SIZE] = {0x00};
  66     int len = 0;
  67
  68     len = strlen(file);
  69     if (len > FILE_PATH_SIZE) len = FILE_PATH_SIZE;
  70     memcpy(filename, file, len);
  71
  72         fLog = fopen(filename, "a");
  73         if (!fLog) {
  74                 printf("Could not append log file %s", filename);
  75                 return;
  76         }
  77
  78         fprintf(fLog, "%s", extData);
  79         fprintf(fLog, "%s\n", c);
  80         fclose(fLog);
  81 }
  82
  83 void AddLogHex(char *fileName, char *extData, const uint8_t * data, const size_t len){
  84         AddLogLine(fileName, extData, sprint_hex(data, len));
  85 }
  86
  87 void AddLogUint64(char *fileName, char *extData, const uint64_t data) {
  88   char buf[100] = {0};
  89         sprintf(buf, "%x%x", (unsigned int)((data & 0xFFFFFFFF00000000) >> 32), (unsigned int)(data & 0xFFFFFFFF));
  90         AddLogLine(fileName, extData, buf);
  91 }
  92
  93 void AddLogCurrentDT(char *fileName) {
  94         char buff[20];
  95         struct tm *curTime;
  96
  97         time_t now = time(0);
  98         curTime = gmtime(&now);
  99
 100         strftime (buff, sizeof(buff), "%Y-%m-%d %H:%M:%S", curTime);
 101         AddLogLine(fileName, "\nanticollision: ", buff);
 102 }
 103
 104 void FillFileNameByUID(char *fileName, uint8_t * uid, char *ext, int byteCount) {
 105         char * fnameptr = fileName;
 106         memset(fileName, 0x00, 200);
 107
 108         for (int j = 0; j < byteCount; j++, fnameptr += 2)
 109                 sprintf(fnameptr, "%02x", (unsigned int) uid[j]);
 110         sprintf(fnameptr, "%s", ext);
 111 }
 112
 113 // fill buffer from structure [{uint8_t data, size_t length},...]
 114 int FillBuffer(uint8_t *data, size_t maxDataLength, size_t *dataLength, ...) {
 115         *dataLength = 0;
 116         va_list valist;
 117         va_start(valist, dataLength);
 118
 119         uint8_t *vdata = NULL;
 120         size_t vlength = 0;
 121         do{
 122                 vdata = va_arg(valist, uint8_t *);
 123                 if (!vdata)
 124                         break;
 125
 126                 vlength = va_arg(valist, size_t);
 127                 if (*dataLength + vlength >  maxDataLength) {
 128                         va_end(valist);
 129                         return 1;
 130                 }
 131
 132                 memcpy(&data[*dataLength], vdata, vlength);
 133                 *dataLength += vlength;
 134
 135         } while (vdata);
 136
 137         va_end(valist);
 138
 139         return 0;
 140 }
 141
 142 void hex_to_buffer(const uint8_t *buf, const uint8_t *hex_data, const size_t hex_len, const size_t hex_max_len,
 143         const size_t min_str_len, const size_t spaces_between, bool uppercase) {
 144
 145         char *tmp = (char *)buf;
 146         size_t i;
 147         memset(tmp, 0x00, hex_max_len);
 148
 149         int maxLen = ( hex_len > hex_max_len) ? hex_max_len : hex_len;
 150
 151         for (i = 0; i < maxLen; ++i, tmp += 2 + spaces_between) {
 152                 sprintf(tmp, (uppercase) ? "%02X" : "%02x", (unsigned int) hex_data[i]);
 153
 154                 for (int j = 0; j < spaces_between; j++)
 155                         sprintf(tmp + 2 + j, " ");
 156         }
 157
 158         i *= (2 + spaces_between);
 159         int minStrLen = min_str_len > i ? min_str_len : 0;
 160         if (minStrLen > hex_max_len)
 161                 minStrLen = hex_max_len;
 162         for(; i < minStrLen; i++, tmp += 1)
 163                 sprintf(tmp, " ");
 164
 165         return;
 166 }
 167
 168 // printing and converting functions
 169
 170 char *sprint_hex(const uint8_t *data, const size_t len) {
 171         static char buf[4097] = {0};
 172
 173         hex_to_buffer((uint8_t *)buf, data, len, sizeof(buf) - 1, 0, 1, false);
 174
 175         return buf;
 176 }
 177
 178 char *sprint_hex_inrow_ex(const uint8_t *data, const size_t len, const size_t min_str_len) {
 179         static char buf[4097] = {0};
 180
 181         hex_to_buffer((uint8_t *)buf, data, len, sizeof(buf) - 1, min_str_len, 0, false);
 182
 183         return buf;
 184 }
 185
 186 char *sprint_hex_inrow(const uint8_t *data, const size_t len) {
 187         return sprint_hex_inrow_ex(data, len, 0);
 188 }
 189
 190 char *sprint_bin_break(const uint8_t *data, const size_t len, const uint8_t breaks) {
 191         // make sure we don't go beyond our char array memory
 192         int max_len;
 193         if (breaks==0)
 194                 max_len = ( len > MAX_BIN_BREAK_LENGTH ) ? MAX_BIN_BREAK_LENGTH : len;
 195         else
 196                 max_len = ( len+(len/breaks) > MAX_BIN_BREAK_LENGTH ) ? MAX_BIN_BREAK_LENGTH : len+(len/breaks);
 197
 198         static char buf[MAX_BIN_BREAK_LENGTH]; // 3072 + end of line characters if broken at 8 bits
 199         //clear memory
 200         memset(buf, 0x00, sizeof(buf));
 201         char *tmp = buf;
 202
 203         size_t in_index = 0;
 204         // loop through the out_index to make sure we don't go too far
 205         for (size_t out_index=0; out_index < max_len; out_index++) {
 206                 // set character - (should be binary but verify it isn't more than 1 digit)
 207                 if (data[in_index]<10)
 208                         sprintf(tmp++, "%u", (unsigned int) data[in_index]);
 209                 // check if a line break is needed and we have room to print it in our array
 210                 if ( (breaks > 0) && !((in_index+1) % breaks) && (out_index+1 < max_len) ) {
 211                         // increment and print line break
 212                         out_index++;
 213                         sprintf(tmp++, "%s","\n");
 214                 }
 215                 in_index++;
 216         }
 217
 218         return buf;
 219 }
 220
 221 char *sprint_bin(const uint8_t *data, const size_t len) {
 222         return sprint_bin_break(data, len, 0);
 223 }
 224
 225 char *sprint_ascii_ex(const uint8_t *data, const size_t len, const size_t min_str_len) {
 226         static char buf[1024];
 227         char *tmp = buf;
 228         memset(buf, 0x00, 1024);
 229         size_t max_len = (len > 1010) ? 1010 : len;
 230         size_t i = 0;
 231         while(i < max_len){
 232                 char c = data[i];
 233                 tmp[i] = ((c < 32) || (c == 127)) ? '.' : c;
 234                 ++i;
 235         }
 236
 237         int minStrLen = min_str_len > i ? min_str_len : 0;
 238         for(; i < minStrLen; ++i)
 239                 tmp[i] = ' ';
 240
 241         return buf;
 242 }
 243
 244 void num_to_bytes(uint64_t n, size_t len, uint8_t* dest)
 245 {
 246         while (len--) {
 247                 dest[len] = (uint8_t) n;
 248                 n >>= 8;
 249         }
 250 }
 251
 252 uint64_t bytes_to_num(uint8_t* src, size_t len)
 253 {
 254         uint64_t num = 0;
 255         while (len--)
 256         {
 257                 num = (num << 8) | (*src);
 258                 src++;
 259         }
 260         return num;
 261 }
 262
 263 void num_to_bytebits(uint64_t   n, size_t len, uint8_t *dest) {
 264         while (len--) {
 265                 dest[len] = n & 1;
 266                 n >>= 1;
 267         }
 268 }
 269
 270 //least significant bit first
 271 void num_to_bytebitsLSBF(uint64_t n, size_t len, uint8_t *dest) {
 272         for(int i = 0 ; i < len ; ++i) {
 273                 dest[i] =  n & 1;
 274                 n >>= 1;
 275         }
 276 }
 277
 278 // Swap bit order on a uint32_t value.  Can be limited by nrbits just use say 8bits reversal
 279 // And clears the rest of the bits.
 280 uint32_t SwapBits(uint32_t value, int nrbits) {
 281         uint32_t newvalue = 0;
 282         for(int i = 0; i < nrbits; i++) {
 283                 newvalue ^= ((value >> i) & 1) << (nrbits - 1 - i);
 284         }
 285         return newvalue;
 286 }
 287
 288 // aa,bb,cc,dd,ee,ff,gg,hh, ii,jj,kk,ll,mm,nn,oo,pp
 289 // to
 290 // hh,gg,ff,ee,dd,cc,bb,aa, pp,oo,nn,mm,ll,kk,jj,ii
 291 // up to 64 bytes or 512 bits
 292 uint8_t *SwapEndian64(const uint8_t *src, const size_t len, const uint8_t blockSize){
 293         static uint8_t buf[64];
 294         memset(buf, 0x00, 64);
 295         uint8_t *tmp = buf;
 296         for (uint8_t block=0; block < (uint8_t)(len/blockSize); block++){
 297                 for (size_t i = 0; i < blockSize; i++){
 298                         tmp[i+(blockSize*block)] = src[(blockSize-1-i)+(blockSize*block)];
 299                 }
 300         }
 301         return tmp;
 302 }
 303
 304 //assumes little endian
 305 char * printBits(size_t const size, void const * const ptr)
 306 {
 307     unsigned char *b = (unsigned char*) ptr;
 308     unsigned char byte;
 309         static char buf[1024];
 310         char * tmp = buf;
 311     int i, j;
 312
 313     for (i=size-1;i>=0;i--)
 314     {
 315         for (j=7;j>=0;j--)
 316         {
 317             byte = b[i] & (1<<j);
 318             byte >>= j;
 319             sprintf(tmp, "%u", (unsigned int)byte);
 320                         tmp++;
 321         }
 322     }
 323         return buf;
 324 }
 325
 326 char * printBitsPar(const uint8_t *b, size_t len) {
 327         static char buf1[512] = {0};
 328         static char buf2[512] = {0};
 329         static char *buf;
 330         if (buf != buf1)
 331                 buf = buf1;
 332         else
 333                 buf = buf2;
 334         memset(buf, 0x00, 512);
 335
 336         for (int i = 0; i < len; i++) {
 337                 buf[i] = ((b[i / 8] << (i % 8)) & 0x80) ? '1':'0';
 338         }
 339         return buf;
 340 }
 341
 342
 343 //  -------------------------------------------------------------------------
 344 //  string parameters lib
 345 //  -------------------------------------------------------------------------
 346
 347 //  -------------------------------------------------------------------------
 348 //  line     - param line
 349 //  bg, en   - symbol numbers in param line of beginning and ending parameter
 350 //  paramnum - param number (from 0)
 351 //  -------------------------------------------------------------------------
 352 int param_getptr(const char *line, int *bg, int *en, int paramnum)
 353 {
 354         int i;
 355         int len = strlen(line);
 356
 357         *bg = 0;
 358         *en = 0;
 359
 360   // skip spaces
 361         while (line[*bg] ==' ' || line[*bg]=='\t') (*bg)++;
 362         if (*bg >= len) {
 363                 return 1;
 364         }
 365
 366         for (i = 0; i < paramnum; i++) {
 367                 while (line[*bg]!=' ' && line[*bg]!='\t' && line[*bg] != '\0') (*bg)++;
 368                 while (line[*bg]==' ' || line[*bg]=='\t') (*bg)++;
 369
 370                 if (line[*bg] == '\0') return 1;
 371         }
 372
 373         *en = *bg;
 374         while (line[*en] != ' ' && line[*en] != '\t' && line[*en] != '\0') (*en)++;
 375
 376         (*en)--;
 377
 378         return 0;
 379 }
 380
 381
 382 int param_getlength(const char *line, int paramnum)
 383 {
 384         int bg, en;
 385
 386         if (param_getptr(line, &bg, &en, paramnum)) return 0;
 387
 388         return en - bg + 1;
 389 }
 390
 391 char param_getchar(const char *line, int paramnum) {
 392         return param_getchar_indx(line, 0, paramnum);
 393 }
 394
 395 char param_getchar_indx(const char *line, int indx, int paramnum) {
 396         int bg, en;
 397
 398         if (param_getptr(line, &bg, &en, paramnum)) return 0x00;
 399
 400         if (bg + indx > en)
 401                 return '\0';
 402
 403         return line[bg + indx];
 404 }
 405
 406 uint8_t param_get8(const char *line, int paramnum)
 407 {
 408         return param_get8ex(line, paramnum, 0, 10);
 409 }
 410
 411 /**
 412  * @brief Reads a decimal integer (actually, 0-254, not 255)
 413  * @param line
 414  * @param paramnum
 415  * @return -1 if error
 416  */
 417 uint8_t param_getdec(const char *line, int paramnum, uint8_t *destination)
 418 {
 419         uint8_t val =  param_get8ex(line, paramnum, 255, 10);
 420         if( (int8_t) val == -1) return 1;
 421         (*destination) = val;
 422         return 0;
 423 }
 424 /**
 425  * @brief Checks if param is decimal
 426  * @param line
 427  * @param paramnum
 428  * @return
 429  */
 430 uint8_t param_isdec(const char *line, int paramnum)
 431 {
 432         int bg, en;
 433         //TODO, check more thorougly
 434         if (!param_getptr(line, &bg, &en, paramnum)) return 1;
 435                 //              return strtoul(&line[bg], NULL, 10) & 0xff;
 436
 437         return 0;
 438 }
 439
 440 uint8_t param_get8ex(const char *line, int paramnum, int deflt, int base)
 441 {
 442         int bg, en;
 443
 444         if (!param_getptr(line, &bg, &en, paramnum))
 445                 return strtoul(&line[bg], NULL, base) & 0xff;
 446         else
 447                 return deflt;
 448 }
 449
 450 uint32_t param_get32ex(const char *line, int paramnum, int deflt, int base)
 451 {
 452         int bg, en;
 453
 454         if (!param_getptr(line, &bg, &en, paramnum))
 455                 return strtoul(&line[bg], NULL, base);
 456         else
 457                 return deflt;
 458 }
 459
 460 uint64_t param_get64ex(const char *line, int paramnum, int deflt, int base)
 461 {
 462         int bg, en;
 463
 464         if (!param_getptr(line, &bg, &en, paramnum))
 465                 return strtoull(&line[bg], NULL, base);
 466         else
 467                 return deflt;
 468 }
 469
 470 int param_gethex(const char *line, int paramnum, uint8_t * data, int hexcnt)
 471 {
 472         int bg, en, temp, i;
 473
 474         if (hexcnt % 2)
 475                 return 1;
 476
 477         if (param_getptr(line, &bg, &en, paramnum)) return 1;
 478
 479         if (en - bg + 1 != hexcnt)
 480                 return 1;
 481
 482         for(i = 0; i < hexcnt; i += 2) {
 483                 if (!(isxdigit((unsigned char)line[bg + i]) && isxdigit((unsigned char)line[bg + i + 1])) )     return 1;
 484
 485                 sscanf((char[]){line[bg + i], line[bg + i + 1], 0}, "%X", &temp);
 486                 data[i / 2] = temp & 0xff;
 487         }
 488
 489         return 0;
 490 }
 491 int param_gethex_ex(const char *line, int paramnum, uint8_t * data, int *hexcnt)
 492 {
 493         int bg, en, temp, i;
 494
 495         //if (hexcnt % 2)
 496         //      return 1;
 497
 498         if (param_getptr(line, &bg, &en, paramnum)) return 1;
 499
 500         *hexcnt = en - bg + 1;
 501         if (*hexcnt % 2) //error if not complete hex bytes
 502                 return 1;
 503
 504         for(i = 0; i < *hexcnt; i += 2) {
 505                 if (!(isxdigit((unsigned char)line[bg + i]) && isxdigit((unsigned char)line[bg + i + 1])) )     return 1;
 506
 507                 sscanf((char[]){line[bg + i], line[bg + i + 1], 0}, "%X", &temp);
 508                 data[i / 2] = temp & 0xff;
 509         }
 510
 511         return 0;
 512 }
 513
 514 int param_gethex_to_eol(const char *line, int paramnum, uint8_t * data, int maxdatalen, int *datalen) {
 515         int bg, en;
 516         uint32_t temp;
 517         char buf[5] = {0};
 518
 519         if (param_getptr(line, &bg, &en, paramnum)) return 1;
 520
 521         *datalen = 0;
 522
 523         int indx = bg;
 524         while (line[indx]) {
 525                 if (line[indx] == '\t' || line[indx] == ' ') {
 526                         indx++;
 527                         continue;
 528                 }
 529
 530                 if (isxdigit((unsigned char)line[indx])) {
 531                         buf[strlen(buf) + 1] = 0x00;
 532                         buf[strlen(buf)] = line[indx];
 533                 } else {
 534                         // if we have symbols other than spaces and hex
 535                         return 1;
 536                 }
 537
 538                 if (*datalen >= maxdatalen) {
 539                         // if we dont have space in buffer and have symbols to translate
 540                         return 2;
 541                 }
 542
 543                 if (strlen(buf) >= 2) {
 544                         sscanf(buf, "%x", &temp);
 545                         data[*datalen] = (uint8_t)(temp & 0xff);
 546                         *buf = 0;
 547                         (*datalen)++;
 548                 }
 549
 550                 indx++;
 551         }
 552
 553         if (strlen(buf) > 0)
 554                 //error when not completed hex bytes
 555                 return 3;
 556
 557         return 0;
 558 }
 559
 560 int param_getstr(const char *line, int paramnum, char * str, size_t buffersize)
 561 {
 562         int bg, en;
 563
 564         if (param_getptr(line, &bg, &en, paramnum)) {
 565                 return 0;
 566         }
 567
 568         // Prevent out of bounds errors
 569         if (en - bg + 1 >= buffersize) {
 570                 printf("out of bounds error: want %d bytes have %zd bytes\n", en - bg + 1 + 1, buffersize);
 571                 return 0;
 572         }
 573
 574         memcpy(str, line + bg, en - bg + 1);
 575         str[en - bg + 1] = 0;
 576
 577         return en - bg + 1;
 578 }
 579
 580 /*
 581 The following methods comes from Rfidler sourcecode.
 582 https://github.com/ApertureLabsLtd/RFIDler/blob/master/firmware/Pic32/RFIDler.X/src/
 583 */
 584
 585 // convert hex to sequence of 0/1 bit values
 586 // returns number of bits converted
 587 int hextobinarray(char *target, char *source)
 588 {
 589     int length, i, count= 0;
 590     char* start = source;
 591     char x;
 592
 593     length = strlen(source);
 594     // process 4 bits (1 hex digit) at a time
 595     while(length--)
 596     {
 597         x= *(source++);
 598         // capitalize
 599         if (x >= 'a' && x <= 'f')
 600             x -= 32;
 601         // convert to numeric value
 602         if (x >= '0' && x <= '9')
 603             x -= '0';
 604         else if (x >= 'A' && x <= 'F')
 605             x -= 'A' - 10;
 606         else {
 607                 printf("Discovered unknown character %c %d at idx %tu of %s\n", x, x, source - start, start);
 608             return 0;
 609         }
 610         // output
 611         for(i= 0 ; i < 4 ; ++i, ++count)
 612             *(target++)= (x >> (3 - i)) & 1;
 613     }
 614
 615     return count;
 616 }
 617
 618 // convert binary array of 0x00/0x01 values to hex (safe to do in place as target will always be shorter than source)
 619 // return number of bits converted
 620 int binarraytohex(char *target,char *source, int length)
 621 {
 622     unsigned char i, x;
 623     int j = length;
 624
 625     if(j % 4)
 626         return 0;
 627
 628     while(j)
 629     {
 630         for(i= x= 0 ; i < 4 ; ++i)
 631             x +=  ( source[i] << (3 - i));
 632         sprintf(target,"%X", (unsigned int)x);
 633         ++target;
 634         source += 4;
 635         j -= 4;
 636     }
 637     return length;
 638 }
 639
 640 // return parity bit required to match type
 641 uint8_t GetParity( uint8_t *bits, uint8_t type, int length)
 642 {
 643     int x;
 644
 645     for(x= 0 ; length > 0 ; --length)
 646         x += bits[length - 1];
 647     x %= 2;
 648
 649     return x ^ type;
 650 }
 651
 652 // add HID parity to binary array: EVEN prefix for 1st half of ID, ODD suffix for 2nd half
 653 void wiegand_add_parity(uint8_t *target, uint8_t *source, uint8_t length)
 654 {
 655     *(target++)= GetParity(source, EVEN, length / 2);
 656     memcpy(target, source, length);
 657     target += length;
 658     *(target)= GetParity(source + length / 2, ODD, length / 2);
 659 }
 660
 661 // xor two arrays together for len items.  The dst array contains the new xored values.
 662 void xor(unsigned char *dst, unsigned char *src, size_t len) {
 663    for( ; len > 0; len--,dst++,src++)
 664        *dst ^= *src;
 665 }
 666
 667 // RotateLeft - Ultralight, Desfire, works on byte level
 668 // 00-01-02  >> 01-02-00
 669 void rol(uint8_t *data, const size_t len){
 670     uint8_t first = data[0];
 671     for (size_t i = 0; i < len-1; i++) {
 672         data[i] = data[i+1];
 673     }
 674     data[len-1] = first;
 675 }
 676
 677
 678 // Replace unprintable characters with a dot in char buffer
 679 void clean_ascii(unsigned char *buf, size_t len) {
 680   for (size_t i = 0; i < len; i++) {
 681     if (!isprint(buf[i]))
 682       buf[i] = '.';
 683   }
 684 }
 685
 686 // replace \r \n to \0
 687 void strcleanrn(char *buf, size_t len) {
 688         strcreplace(buf, len, '\n', '\0');
 689         strcreplace(buf, len, '\r', '\0');
 690 }
 691
 692 // replace char in buffer
 693 void strcreplace(char *buf, size_t len, char from, char to) {
 694   for (size_t i = 0; i < len; i++) {
 695     if (buf[i] == from)
 696       buf[i] = to;
 697   }
 698 }
 699
 700 char *strmcopy(char *buf) {
 701         char * str = NULL;
 702         if ((str = (char*) malloc(strlen(buf) + 1)) != NULL) {
 703                 memset(str, 0, strlen(buf) + 1);
 704                 strcpy(str, buf);
 705         }
 706         return str;
 707 }
 708
 709
 710 // determine number of logical CPU cores (use for multithreaded functions)
 711 extern int num_CPUs(void)
 712 {
 713 #if defined(_WIN32)
 714         #include <sysinfoapi.h>
 715         SYSTEM_INFO sysinfo;
 716         GetSystemInfo(&sysinfo);
 717         return sysinfo.dwNumberOfProcessors;
 718 #elif defined(__linux__) || defined(__APPLE__)
 719         #include <unistd.h>
 720         return sysconf(_SC_NPROCESSORS_ONLN);
 721 #else
 722         return 1;
 723 #endif
 724 }
 725