cvs.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 #include <stdarg.h>
  20
  21 #ifdef _WIN32
  22 #include <windows.h>
  23 #endif
  24
  25 #define MAX_BIN_BREAK_LENGTH   (3072+384+1)
  26
  27 #ifndef _WIN32
  28 #include <termios.h>
  29 #include <sys/ioctl.h>
  30 #include <unistd.h>
  31
  32 int ukbhit(void)
  33 {
  34   int cnt = 0;
  35   int error;
  36   static struct termios Otty, Ntty;
  37
  38   if ( tcgetattr(STDIN_FILENO, &Otty) == -1 ) return -1;
  39   Ntty = Otty;
  40
  41   Ntty.c_iflag          = 0x0000;   // input mode
  42   Ntty.c_oflag          = 0x0000;   // output mode
  43   Ntty.c_lflag         &= ~ICANON;  // control mode = raw
  44   Ntty.c_cc[VMIN]       = 1;        // return if at least 1 character is in the queue
  45   Ntty.c_cc[VTIME]      = 0;        // no timeout. Wait forever
  46
  47   if (0 == (error = tcsetattr(STDIN_FILENO, TCSANOW, &Ntty))) {   // set new attributes
  48     error += ioctl(STDIN_FILENO, FIONREAD, &cnt);                 // get number of characters availabe
  49     error += tcsetattr(STDIN_FILENO, TCSANOW, &Otty);             // reset attributes
  50   }
  51
  52   return ( error == 0 ? cnt : -1 );
  53 }
  54
  55 #else
  56
  57 #include <conio.h>
  58 int ukbhit(void) {
  59         return kbhit();
  60 }
  61 #endif
  62
  63 // log files functions
  64 void AddLogLine(char *file, char *extData, char *c) {
  65         FILE *fLog = NULL;
  66     char filename[FILE_PATH_SIZE] = {0x00};
  67     int len = 0;
  68
  69     len = strlen(file);
  70     if (len > FILE_PATH_SIZE) len = FILE_PATH_SIZE;
  71     memcpy(filename, file, len);
  72
  73         fLog = fopen(filename, "a");
  74         if (!fLog) {
  75                 printf("Could not append log file %s", filename);
  76                 return;
  77         }
  78
  79         fprintf(fLog, "%s", extData);
  80         fprintf(fLog, "%s\n", c);
  81         fclose(fLog);
  82 }
  83
  84 void AddLogHex(char *fileName, char *extData, const uint8_t * data, const size_t len){
  85         AddLogLine(fileName, extData, sprint_hex(data, len));
  86 }
  87
  88 void AddLogUint64(char *fileName, char *extData, const uint64_t data) {
  89   char buf[100] = {0};
  90         sprintf(buf, "%x%x", (unsigned int)((data & 0xFFFFFFFF00000000) >> 32), (unsigned int)(data & 0xFFFFFFFF));
  91         AddLogLine(fileName, extData, buf);
  92 }
  93
  94 void AddLogCurrentDT(char *fileName) {
  95         char buff[20];
  96         struct tm *curTime;
  97
  98         time_t now = time(0);
  99         curTime = gmtime(&now);
 100
 101         strftime (buff, sizeof(buff), "%Y-%m-%d %H:%M:%S", curTime);
 102         AddLogLine(fileName, "\nanticollision: ", buff);
 103 }
 104
 105 void FillFileNameByUID(char *fileName, uint8_t * uid, char *ext, int byteCount) {
 106         char * fnameptr = fileName;
 107         memset(fileName, 0x00, 200);
 108
 109         for (int j = 0; j < byteCount; j++, fnameptr += 2)
 110                 sprintf(fnameptr, "%02x", (unsigned int) uid[j]);
 111         sprintf(fnameptr, "%s", ext);
 112 }
 113
 114 // fill buffer from structure [{uint8_t data, size_t length},...]
 115 int FillBuffer(uint8_t *data, size_t maxDataLength, size_t *dataLength, ...) {
 116         *dataLength = 0;
 117         va_list valist;
 118         va_start(valist, dataLength);
 119
 120         uint8_t *vdata = NULL;
 121         size_t vlength = 0;
 122         do{
 123                 vdata = va_arg(valist, uint8_t *);
 124                 if (!vdata)
 125                         break;
 126
 127                 vlength = va_arg(valist, size_t);
 128                 if (*dataLength + vlength >  maxDataLength) {
 129                         va_end(valist);
 130                         return 1;
 131                 }
 132
 133                 memcpy(&data[*dataLength], vdata, vlength);
 134                 *dataLength += vlength;
 135
 136         } while (vdata);
 137
 138         va_end(valist);
 139
 140         return 0;
 141 }
 142
 143 void hex_to_buffer(const uint8_t *buf, const uint8_t *hex_data, const size_t hex_len, const size_t hex_max_len,
 144         const size_t min_str_len, const size_t spaces_between, bool uppercase) {
 145
 146         char *tmp = (char *)buf;
 147         size_t i;
 148         memset(tmp, 0x00, hex_max_len);
 149
 150         int maxLen = ( hex_len > hex_max_len) ? hex_max_len : hex_len;
 151
 152         for (i = 0; i < maxLen; ++i, tmp += 2 + spaces_between) {
 153                 sprintf(tmp, (uppercase) ? "%02X" : "%02x", (unsigned int) hex_data[i]);
 154
 155                 for (int j = 0; j < spaces_between; j++)
 156                         sprintf(tmp + 2 + j, " ");
 157         }
 158
 159         i *= (2 + spaces_between);
 160         int minStrLen = min_str_len > i ? min_str_len : 0;
 161         if (minStrLen > hex_max_len)
 162                 minStrLen = hex_max_len;
 163         for(; i < minStrLen; i++, tmp += 1)
 164                 sprintf(tmp, " ");
 165
 166         return;
 167 }
 168
 169 // printing and converting functions
 170
 171 char *sprint_hex(const uint8_t *data, const size_t len) {
 172         static char buf[4097] = {0};
 173
 174         hex_to_buffer((uint8_t *)buf, data, len, sizeof(buf) - 1, 0, 1, false);
 175
 176         return buf;
 177 }
 178
 179 char *sprint_hex_inrow_ex(const uint8_t *data, const size_t len, const size_t min_str_len) {
 180         static char buf[4097] = {0};
 181
 182         hex_to_buffer((uint8_t *)buf, data, len, sizeof(buf) - 1, min_str_len, 0, false);
 183
 184         return buf;
 185 }
 186
 187 char *sprint_hex_inrow(const uint8_t *data, const size_t len) {
 188         return sprint_hex_inrow_ex(data, len, 0);
 189 }
 190
 191 char *sprint_bin_break(const uint8_t *data, const size_t len, const uint8_t breaks) {
 192         // make sure we don't go beyond our char array memory
 193         int max_len;
 194         if (breaks==0)
 195                 max_len = ( len > MAX_BIN_BREAK_LENGTH ) ? MAX_BIN_BREAK_LENGTH : len;
 196         else
 197                 max_len = ( len+(len/breaks) > MAX_BIN_BREAK_LENGTH ) ? MAX_BIN_BREAK_LENGTH : len+(len/breaks);
 198
 199         static char buf[MAX_BIN_BREAK_LENGTH]; // 3072 + end of line characters if broken at 8 bits
 200         //clear memory
 201         memset(buf, 0x00, sizeof(buf));
 202         char *tmp = buf;
 203
 204         size_t in_index = 0;
 205         // loop through the out_index to make sure we don't go too far
 206         for (size_t out_index=0; out_index < max_len; out_index++) {
 207                 // set character - (should be binary but verify it isn't more than 1 digit)
 208                 if (data[in_index]<10)
 209                         sprintf(tmp++, "%u", (unsigned int) data[in_index]);
 210                 // check if a line break is needed and we have room to print it in our array
 211                 if ( (breaks > 0) && !((in_index+1) % breaks) && (out_index+1 < max_len) ) {
 212                         // increment and print line break
 213                         out_index++;
 214                         sprintf(tmp++, "%s","\n");
 215                 }
 216                 in_index++;
 217         }
 218
 219         return buf;
 220 }
 221
 222 char *sprint_bin(const uint8_t *data, const size_t len) {
 223         return sprint_bin_break(data, len, 0);
 224 }
 225
 226 char *sprint_ascii_ex(const uint8_t *data, const size_t len, const size_t min_str_len) {
 227         static char buf[1024];
 228         char *tmp = buf;
 229         memset(buf, 0x00, 1024);
 230         size_t max_len = (len > 1010) ? 1010 : len;
 231         size_t i = 0;
 232         while(i < max_len){
 233                 char c = data[i];
 234                 tmp[i] = ((c < 32) || (c == 127)) ? '.' : c;
 235                 ++i;
 236         }
 237
 238         int minStrLen = min_str_len > i ? min_str_len : 0;
 239         for(; i < minStrLen; ++i)
 240                 tmp[i] = ' ';
 241
 242         return buf;
 243 }
 244
 245 void num_to_bytes(uint64_t n, size_t len, uint8_t* dest)
 246 {
 247         while (len--) {
 248                 dest[len] = (uint8_t) n;
 249                 n >>= 8;
 250         }
 251 }
 252
 253 uint64_t bytes_to_num(uint8_t* src, size_t len)
 254 {
 255         uint64_t num = 0;
 256         while (len--)
 257         {
 258                 num = (num << 8) | (*src);
 259                 src++;
 260         }
 261         return num;
 262 }
 263
 264 void num_to_bytebits(uint64_t   n, size_t len, uint8_t *dest) {
 265         while (len--) {
 266                 dest[len] = n & 1;
 267                 n >>= 1;
 268         }
 269 }
 270
 271 //least significant bit first
 272 void num_to_bytebitsLSBF(uint64_t n, size_t len, uint8_t *dest) {
 273         for(int i = 0 ; i < len ; ++i) {
 274                 dest[i] =  n & 1;
 275                 n >>= 1;
 276         }
 277 }
 278
 279 // Swap bit order on a uint32_t value.  Can be limited by nrbits just use say 8bits reversal
 280 // And clears the rest of the bits.
 281 uint32_t SwapBits(uint32_t value, int nrbits) {
 282         uint32_t newvalue = 0;
 283         for(int i = 0; i < nrbits; i++) {
 284                 newvalue ^= ((value >> i) & 1) << (nrbits - 1 - i);
 285         }
 286         return newvalue;
 287 }
 288
 289 // aa,bb,cc,dd,ee,ff,gg,hh, ii,jj,kk,ll,mm,nn,oo,pp
 290 // to
 291 // hh,gg,ff,ee,dd,cc,bb,aa, pp,oo,nn,mm,ll,kk,jj,ii
 292 // up to 64 bytes or 512 bits
 293 uint8_t *SwapEndian64(const uint8_t *src, const size_t len, const uint8_t blockSize){
 294         static uint8_t buf[64];
 295         memset(buf, 0x00, 64);
 296         uint8_t *tmp = buf;
 297         for (uint8_t block=0; block < (uint8_t)(len/blockSize); block++){
 298                 for (size_t i = 0; i < blockSize; i++){
 299                         tmp[i+(blockSize*block)] = src[(blockSize-1-i)+(blockSize*block)];
 300                 }
 301         }
 302         return tmp;
 303 }
 304
 305 //assumes little endian
 306 char * printBits(size_t const size, void const * const ptr)
 307 {
 308     unsigned char *b = (unsigned char*) ptr;
 309     unsigned char byte;
 310         static char buf[1024];
 311         char * tmp = buf;
 312     int i, j;
 313
 314     for (i=size-1;i>=0;i--)
 315     {
 316         for (j=7;j>=0;j--)
 317         {
 318             byte = b[i] & (1<<j);
 319             byte >>= j;
 320             sprintf(tmp, "%u", (unsigned int)byte);
 321                         tmp++;
 322         }
 323     }
 324         return buf;
 325 }
 326
 327 char * printBitsPar(const uint8_t *b, size_t len) {
 328         static char buf1[512] = {0};
 329         static char buf2[512] = {0};
 330         static char *buf;
 331         if (buf != buf1)
 332                 buf = buf1;
 333         else
 334                 buf = buf2;
 335         memset(buf, 0x00, 512);
 336
 337         for (int i = 0; i < len; i++) {
 338                 buf[i] = ((b[i / 8] << (i % 8)) & 0x80) ? '1':'0';
 339         }
 340         return buf;
 341 }
 342
 343
 344 //  -------------------------------------------------------------------------
 345 //  string parameters lib
 346 //  -------------------------------------------------------------------------
 347
 348 //  -------------------------------------------------------------------------
 349 //  line     - param line
 350 //  bg, en   - symbol numbers in param line of beginning and ending parameter
 351 //  paramnum - param number (from 0)
 352 //  -------------------------------------------------------------------------
 353 int param_getptr(const char *line, int *bg, int *en, int paramnum)
 354 {
 355         int i;
 356         int len = strlen(line);
 357
 358         *bg = 0;
 359         *en = 0;
 360
 361   // skip spaces
 362         while (line[*bg] ==' ' || line[*bg]=='\t') (*bg)++;
 363         if (*bg >= len) {
 364                 return 1;
 365         }
 366
 367         for (i = 0; i < paramnum; i++) {
 368                 while (line[*bg]!=' ' && line[*bg]!='\t' && line[*bg] != '\0') (*bg)++;
 369                 while (line[*bg]==' ' || line[*bg]=='\t') (*bg)++;
 370
 371                 if (line[*bg] == '\0') return 1;
 372         }
 373
 374         *en = *bg;
 375         while (line[*en] != ' ' && line[*en] != '\t' && line[*en] != '\0') (*en)++;
 376
 377         (*en)--;
 378
 379         return 0;
 380 }
 381
 382
 383 int param_getlength(const char *line, int paramnum)
 384 {
 385         int bg, en;
 386
 387         if (param_getptr(line, &bg, &en, paramnum)) return 0;
 388
 389         return en - bg + 1;
 390 }
 391
 392 char param_getchar(const char *line, int paramnum) {
 393         return param_getchar_indx(line, 0, paramnum);
 394 }
 395
 396 char param_getchar_indx(const char *line, int indx, int paramnum) {
 397         int bg, en;
 398
 399         if (param_getptr(line, &bg, &en, paramnum)) return 0x00;
 400
 401         if (bg + indx > en)
 402                 return '\0';
 403
 404         return line[bg + indx];
 405 }
 406
 407 uint8_t param_get8(const char *line, int paramnum)
 408 {
 409         return param_get8ex(line, paramnum, 0, 10);
 410 }
 411
 412 /**
 413  * @brief Reads a decimal integer (actually, 0-254, not 255)
 414  * @param line
 415  * @param paramnum
 416  * @return -1 if error
 417  */
 418 uint8_t param_getdec(const char *line, int paramnum, uint8_t *destination)
 419 {
 420         uint8_t val =  param_get8ex(line, paramnum, 255, 10);
 421         if( (int8_t) val == -1) return 1;
 422         (*destination) = val;
 423         return 0;
 424 }
 425 /**
 426  * @brief Checks if param is decimal
 427  * @param line
 428  * @param paramnum
 429  * @return
 430  */
 431 uint8_t param_isdec(const char *line, int paramnum)
 432 {
 433         int bg, en;
 434         //TODO, check more thorougly
 435         if (!param_getptr(line, &bg, &en, paramnum)) return 1;
 436                 //              return strtoul(&line[bg], NULL, 10) & 0xff;
 437
 438         return 0;
 439 }
 440
 441 uint8_t param_get8ex(const char *line, int paramnum, int deflt, int base)
 442 {
 443         int bg, en;
 444
 445         if (!param_getptr(line, &bg, &en, paramnum))
 446                 return strtoul(&line[bg], NULL, base) & 0xff;
 447         else
 448                 return deflt;
 449 }
 450
 451 uint32_t param_get32ex(const char *line, int paramnum, int deflt, int base)
 452 {
 453         int bg, en;
 454
 455         if (!param_getptr(line, &bg, &en, paramnum))
 456                 return strtoul(&line[bg], NULL, base);
 457         else
 458                 return deflt;
 459 }
 460
 461 uint64_t param_get64ex(const char *line, int paramnum, int deflt, int base)
 462 {
 463         int bg, en;
 464
 465         if (!param_getptr(line, &bg, &en, paramnum))
 466                 return strtoull(&line[bg], NULL, base);
 467         else
 468                 return deflt;
 469 }
 470
 471 int param_gethex(const char *line, int paramnum, uint8_t * data, int hexcnt)
 472 {
 473         int bg, en, temp, i;
 474
 475         if (hexcnt % 2)
 476                 return 1;
 477
 478         if (param_getptr(line, &bg, &en, paramnum)) return 1;
 479
 480         if (en - bg + 1 != hexcnt)
 481                 return 1;
 482
 483         for(i = 0; i < hexcnt; i += 2) {
 484                 if (!(isxdigit((unsigned char)line[bg + i]) && isxdigit((unsigned char)line[bg + i + 1])) )     return 1;
 485
 486                 sscanf((char[]){line[bg + i], line[bg + i + 1], 0}, "%X", &temp);
 487                 data[i / 2] = temp & 0xff;
 488         }
 489
 490         return 0;
 491 }
 492 int param_gethex_ex(const char *line, int paramnum, uint8_t * data, int *hexcnt)
 493 {
 494         int bg, en, temp, i;
 495
 496         //if (hexcnt % 2)
 497         //      return 1;
 498
 499         if (param_getptr(line, &bg, &en, paramnum)) return 1;
 500
 501         *hexcnt = en - bg + 1;
 502         if (*hexcnt % 2) //error if not complete hex bytes
 503                 return 1;
 504
 505         for(i = 0; i < *hexcnt; i += 2) {
 506                 if (!(isxdigit((unsigned char)line[bg + i]) && isxdigit((unsigned char)line[bg + i + 1])) )     return 1;
 507
 508                 sscanf((char[]){line[bg + i], line[bg + i + 1], 0}, "%X", &temp);
 509                 data[i / 2] = temp & 0xff;
 510         }
 511
 512         return 0;
 513 }
 514
 515 int param_gethex_to_eol(const char *line, int paramnum, uint8_t * data, int maxdatalen, int *datalen) {
 516         int bg, en;
 517         uint32_t temp;
 518         char buf[5] = {0};
 519
 520         if (param_getptr(line, &bg, &en, paramnum)) return 1;
 521
 522         *datalen = 0;
 523
 524         int indx = bg;
 525         while (line[indx]) {
 526                 if (line[indx] == '\t' || line[indx] == ' ') {
 527                         indx++;
 528                         continue;
 529                 }
 530
 531                 if (isxdigit((unsigned char)line[indx])) {
 532                         buf[strlen(buf) + 1] = 0x00;
 533                         buf[strlen(buf)] = line[indx];
 534                 } else {
 535                         // if we have symbols other than spaces and hex
 536                         return 1;
 537                 }
 538
 539                 if (*datalen >= maxdatalen) {
 540                         // if we dont have space in buffer and have symbols to translate
 541                         return 2;
 542                 }
 543
 544                 if (strlen(buf) >= 2) {
 545                         sscanf(buf, "%x", &temp);
 546                         data[*datalen] = (uint8_t)(temp & 0xff);
 547                         *buf = 0;
 548                         (*datalen)++;
 549                 }
 550
 551                 indx++;
 552         }
 553
 554         if (strlen(buf) > 0)
 555                 //error when not completed hex bytes
 556                 return 3;
 557
 558         return 0;
 559 }
 560
 561 int param_getstr(const char *line, int paramnum, char * str, size_t buffersize)
 562 {
 563         int bg, en;
 564
 565         if (param_getptr(line, &bg, &en, paramnum)) {
 566                 return 0;
 567         }
 568
 569         // Prevent out of bounds errors
 570         if (en - bg + 1 >= buffersize) {
 571                 printf("out of bounds error: want %d bytes have %zd bytes\n", en - bg + 1 + 1, buffersize);
 572                 return 0;
 573         }
 574
 575         memcpy(str, line + bg, en - bg + 1);
 576         str[en - bg + 1] = 0;
 577
 578         return en - bg + 1;
 579 }
 580
 581 /*
 582 The following methods comes from Rfidler sourcecode.
 583 https://github.com/ApertureLabsLtd/RFIDler/blob/master/firmware/Pic32/RFIDler.X/src/
 584 */
 585
 586 // convert hex to sequence of 0/1 bit values
 587 // returns number of bits converted
 588 int hextobinarray(char *target, char *source)
 589 {
 590     int length, i, count= 0;
 591     char* start = source;
 592     char x;
 593
 594     length = strlen(source);
 595     // process 4 bits (1 hex digit) at a time
 596     while(length--)
 597     {
 598         x= *(source++);
 599         // capitalize
 600         if (x >= 'a' && x <= 'f')
 601             x -= 32;
 602         // convert to numeric value
 603         if (x >= '0' && x <= '9')
 604             x -= '0';
 605         else if (x >= 'A' && x <= 'F')
 606             x -= 'A' - 10;
 607         else {
 608                 printf("Discovered unknown character %c %d at idx %tu of %s\n", x, x, source - start, start);
 609             return 0;
 610         }
 611         // output
 612         for(i= 0 ; i < 4 ; ++i, ++count)
 613             *(target++)= (x >> (3 - i)) & 1;
 614     }
 615
 616     return count;
 617 }
 618
 619 // convert binary array of 0x00/0x01 values to hex (safe to do in place as target will always be shorter than source)
 620 // return number of bits converted
 621 int binarraytohex(char *target,char *source, int length)
 622 {
 623     unsigned char i, x;
 624     int j = length;
 625
 626     if(j % 4)
 627         return 0;
 628
 629     while(j)
 630     {
 631         for(i= x= 0 ; i < 4 ; ++i)
 632             x +=  ( source[i] << (3 - i));
 633         sprintf(target,"%X", (unsigned int)x);
 634         ++target;
 635         source += 4;
 636         j -= 4;
 637     }
 638     return length;
 639 }
 640
 641 // return parity bit required to match type
 642 uint8_t GetParity( uint8_t *bits, uint8_t type, int length)
 643 {
 644     int x;
 645
 646     for(x= 0 ; length > 0 ; --length)
 647         x += bits[length - 1];
 648     x %= 2;
 649
 650     return x ^ type;
 651 }
 652
 653 // add HID parity to binary array: EVEN prefix for 1st half of ID, ODD suffix for 2nd half
 654 void wiegand_add_parity(uint8_t *target, uint8_t *source, uint8_t length)
 655 {
 656     *(target++)= GetParity(source, EVEN, length / 2);
 657     memcpy(target, source, length);
 658     target += length;
 659     *(target)= GetParity(source + length / 2, ODD, length / 2);
 660 }
 661
 662 // xor two arrays together for len items.  The dst array contains the new xored values.
 663 void xor(unsigned char *dst, unsigned char *src, size_t len) {
 664    for( ; len > 0; len--,dst++,src++)
 665        *dst ^= *src;
 666 }
 667
 668 // RotateLeft - Ultralight, Desfire, works on byte level
 669 // 00-01-02  >> 01-02-00
 670 void rol(uint8_t *data, const size_t len){
 671     uint8_t first = data[0];
 672     for (size_t i = 0; i < len-1; i++) {
 673         data[i] = data[i+1];
 674     }
 675     data[len-1] = first;
 676 }
 677
 678
 679 // Replace unprintable characters with a dot in char buffer
 680 void clean_ascii(unsigned char *buf, size_t len) {
 681   for (size_t i = 0; i < len; i++) {
 682     if (!isprint(buf[i]))
 683       buf[i] = '.';
 684   }
 685 }
 686
 687 // replace \r \n to \0
 688 void strcleanrn(char *buf, size_t len) {
 689         strcreplace(buf, len, '\n', '\0');
 690         strcreplace(buf, len, '\r', '\0');
 691 }
 692
 693 // replace char in buffer
 694 void strcreplace(char *buf, size_t len, char from, char to) {
 695   for (size_t i = 0; i < len; i++) {
 696     if (buf[i] == from)
 697       buf[i] = to;
 698   }
 699 }
 700
 701 char *strmcopy(char *buf) {
 702         char * str = NULL;
 703         if ((str = (char*) malloc(strlen(buf) + 1)) != NULL) {
 704                 memset(str, 0, strlen(buf) + 1);
 705                 strcpy(str, buf);
 706         }
 707         return str;
 708 }
 709
 710
 711 // determine number of logical CPU cores (use for multithreaded functions)
 712 extern int num_CPUs(void)
 713 {
 714 #if defined(_WIN32)
 715         #include <sysinfoapi.h>
 716         SYSTEM_INFO sysinfo;
 717         GetSystemInfo(&sysinfo);
 718         return sysinfo.dwNumberOfProcessors;
 719 #elif defined(__linux__) || defined(__APPLE__)
 720         #include <unistd.h>
 721         return sysconf(_SC_NPROCESSORS_ONLN);
 722 #else
 723         return 1;
 724 #endif
 725 }
 726