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 #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 char getch(void)
  56 {
  57         char c;
  58         int error;
  59         struct termios Otty, Ntty;
  60         if ( tcgetattr(STDIN_FILENO, &Otty) == -1 ) return -1;
  61         Ntty = Otty;
  62         Ntty.c_lflag &= ~ICANON; /* disable buffered i/o */
  63         if (0 == (error = tcsetattr(STDIN_FILENO, TCSANOW, &Ntty))) {   // set new attributes
  64                 c = getchar();
  65                 error += tcsetattr(STDIN_FILENO, TCSANOW, &Otty);           // reset attributes
  66         }
  67         return ( error == 0 ? c : -1 );
  68 }
  69
  70 #else // _WIN32
  71
  72 #include <conio.h>
  73 int ukbhit(void) {
  74         return kbhit();
  75 }
  76 #endif
  77
  78 // log files functions
  79 void AddLogLine(char *file, char *extData, char *c) {
  80         FILE *fLog = NULL;
  81     char filename[FILE_PATH_SIZE] = {0x00};
  82     int len = 0;
  83
  84     len = strlen(file);
  85     if (len > FILE_PATH_SIZE) len = FILE_PATH_SIZE;
  86     memcpy(filename, file, len);
  87
  88         fLog = fopen(filename, "a");
  89         if (!fLog) {
  90                 printf("Could not append log file %s", filename);
  91                 return;
  92         }
  93
  94         fprintf(fLog, "%s", extData);
  95         fprintf(fLog, "%s\n", c);
  96         fclose(fLog);
  97 }
  98
  99 void AddLogHex(char *fileName, char *extData, const uint8_t * data, const size_t len){
 100         AddLogLine(fileName, extData, sprint_hex(data, len));
 101 }
 102
 103 void AddLogUint64(char *fileName, char *extData, const uint64_t data) {
 104   char buf[100] = {0};
 105         sprintf(buf, "%x%x", (unsigned int)((data & 0xFFFFFFFF00000000) >> 32), (unsigned int)(data & 0xFFFFFFFF));
 106         AddLogLine(fileName, extData, buf);
 107 }
 108
 109 void AddLogCurrentDT(char *fileName) {
 110         char buff[20];
 111         struct tm *curTime;
 112
 113         time_t now = time(0);
 114         curTime = gmtime(&now);
 115
 116         strftime (buff, sizeof(buff), "%Y-%m-%d %H:%M:%S", curTime);
 117         AddLogLine(fileName, "\nanticollision: ", buff);
 118 }
 119
 120 void FillFileNameByUID(char *fileName, uint8_t * uid, char *ext, int byteCount) {
 121         char * fnameptr = fileName;
 122         memset(fileName, 0x00, 200);
 123
 124         for (int j = 0; j < byteCount; j++, fnameptr += 2)
 125                 sprintf(fnameptr, "%02x", (unsigned int) uid[j]);
 126         sprintf(fnameptr, "%s", ext);
 127 }
 128
 129 // fill buffer from structure [{uint8_t data, size_t length},...]
 130 int FillBuffer(uint8_t *data, size_t maxDataLength, size_t *dataLength, ...) {
 131         *dataLength = 0;
 132         va_list valist;
 133         va_start(valist, dataLength);
 134
 135         uint8_t *vdata = NULL;
 136         size_t vlength = 0;
 137         do{
 138                 vdata = va_arg(valist, uint8_t *);
 139                 if (!vdata)
 140                         break;
 141
 142                 vlength = va_arg(valist, size_t);
 143                 if (*dataLength + vlength >  maxDataLength) {
 144                         va_end(valist);
 145                         return 1;
 146                 }
 147
 148                 memcpy(&data[*dataLength], vdata, vlength);
 149                 *dataLength += vlength;
 150
 151         } while (vdata);
 152
 153         va_end(valist);
 154
 155         return 0;
 156 }
 157
 158 bool CheckStringIsHEXValue(const char *value) {
 159         for (int i = 0; i < strlen(value); i++)
 160                 if (!isxdigit(value[i]))
 161                         return false;
 162
 163         if (strlen(value) % 2)
 164                 return false;
 165
 166         return true;
 167 }
 168
 169 void hex_to_buffer(const uint8_t *buf, const uint8_t *hex_data, const size_t hex_len, const size_t hex_max_len,
 170         const size_t min_str_len, const size_t spaces_between, bool uppercase) {
 171
 172         char *tmp = (char *)buf;
 173         size_t i;
 174         memset(tmp, 0x00, hex_max_len);
 175
 176         int maxLen = ( hex_len > hex_max_len) ? hex_max_len : hex_len;
 177
 178         for (i = 0; i < maxLen; ++i, tmp += 2 + spaces_between) {
 179                 sprintf(tmp, (uppercase) ? "%02X" : "%02x", (unsigned int) hex_data[i]);
 180
 181                 for (int j = 0; j < spaces_between; j++)
 182                         sprintf(tmp + 2 + j, " ");
 183         }
 184
 185         i *= (2 + spaces_between);
 186         int minStrLen = min_str_len > i ? min_str_len : 0;
 187         if (minStrLen > hex_max_len)
 188                 minStrLen = hex_max_len;
 189         for(; i < minStrLen; i++, tmp += 1)
 190                 sprintf(tmp, " ");
 191
 192         return;
 193 }
 194
 195 // printing and converting functions
 196
 197 char *sprint_hex(const uint8_t *data, const size_t len) {
 198         static char buf[4097] = {0};
 199
 200         hex_to_buffer((uint8_t *)buf, data, len, sizeof(buf) - 1, 0, 1, false);
 201
 202         return buf;
 203 }
 204
 205 char *sprint_hex_inrow_ex(const uint8_t *data, const size_t len, const size_t min_str_len) {
 206         static char buf[4097] = {0};
 207
 208         hex_to_buffer((uint8_t *)buf, data, len, sizeof(buf) - 1, min_str_len, 0, false);
 209
 210         return buf;
 211 }
 212
 213 char *sprint_hex_inrow(const uint8_t *data, const size_t len) {
 214         return sprint_hex_inrow_ex(data, len, 0);
 215 }
 216
 217 char *sprint_bin_break(const uint8_t *data, const size_t len, const uint8_t breaks) {
 218         // make sure we don't go beyond our char array memory
 219         int max_len;
 220         if (breaks==0)
 221                 max_len = ( len > MAX_BIN_BREAK_LENGTH ) ? MAX_BIN_BREAK_LENGTH : len;
 222         else
 223                 max_len = ( len+(len/breaks) > MAX_BIN_BREAK_LENGTH ) ? MAX_BIN_BREAK_LENGTH : len+(len/breaks);
 224
 225         static char buf[MAX_BIN_BREAK_LENGTH]; // 3072 + end of line characters if broken at 8 bits
 226         //clear memory
 227         memset(buf, 0x00, sizeof(buf));
 228         char *tmp = buf;
 229
 230         size_t in_index = 0;
 231         // loop through the out_index to make sure we don't go too far
 232         for (size_t out_index=0; out_index < max_len; out_index++) {
 233                 // set character - (should be binary but verify it isn't more than 1 digit)
 234                 if (data[in_index]<10)
 235                         sprintf(tmp++, "%u", (unsigned int) data[in_index]);
 236                 // check if a line break is needed and we have room to print it in our array
 237                 if ( (breaks > 0) && !((in_index+1) % breaks) && (out_index+1 < max_len) ) {
 238                         // increment and print line break
 239                         out_index++;
 240                         sprintf(tmp++, "%s","\n");
 241                 }
 242                 in_index++;
 243         }
 244
 245         return buf;
 246 }
 247
 248 char *sprint_bin(const uint8_t *data, const size_t len) {
 249         return sprint_bin_break(data, len, 0);
 250 }
 251
 252 char *sprint_ascii_ex(const uint8_t *data, const size_t len, const size_t min_str_len) {
 253         static char buf[1024];
 254         char *tmp = buf;
 255         memset(buf, 0x00, 1024);
 256         size_t max_len = (len > 1010) ? 1010 : len;
 257         size_t i = 0;
 258         while(i < max_len){
 259                 char c = data[i];
 260                 tmp[i] = ((c < 32) || (c == 127)) ? '.' : c;
 261                 ++i;
 262         }
 263
 264         int minStrLen = min_str_len > i ? min_str_len : 0;
 265         for(; i < minStrLen; ++i)
 266                 tmp[i] = ' ';
 267
 268         return buf;
 269 }
 270
 271 void num_to_bytes(uint64_t n, size_t len, uint8_t* dest)
 272 {
 273         while (len--) {
 274                 dest[len] = (uint8_t) n;
 275                 n >>= 8;
 276         }
 277 }
 278
 279 uint64_t bytes_to_num(uint8_t* src, size_t len)
 280 {
 281         uint64_t num = 0;
 282         while (len--)
 283         {
 284                 num = (num << 8) | (*src);
 285                 src++;
 286         }
 287         return num;
 288 }
 289
 290 void num_to_bytebits(uint64_t   n, size_t len, uint8_t *dest) {
 291         while (len--) {
 292                 dest[len] = n & 1;
 293                 n >>= 1;
 294         }
 295 }
 296
 297 //least significant bit first
 298 void num_to_bytebitsLSBF(uint64_t n, size_t len, uint8_t *dest) {
 299         for(int i = 0 ; i < len ; ++i) {
 300                 dest[i] =  n & 1;
 301                 n >>= 1;
 302         }
 303 }
 304
 305 // Swap bit order on a uint32_t value.  Can be limited by nrbits just use say 8bits reversal
 306 // And clears the rest of the bits.
 307 uint32_t SwapBits(uint32_t value, int nrbits) {
 308         uint32_t newvalue = 0;
 309         for(int i = 0; i < nrbits; i++) {
 310                 newvalue ^= ((value >> i) & 1) << (nrbits - 1 - i);
 311         }
 312         return newvalue;
 313 }
 314
 315 // aa,bb,cc,dd,ee,ff,gg,hh, ii,jj,kk,ll,mm,nn,oo,pp
 316 // to
 317 // hh,gg,ff,ee,dd,cc,bb,aa, pp,oo,nn,mm,ll,kk,jj,ii
 318 // up to 64 bytes or 512 bits
 319 uint8_t *SwapEndian64(const uint8_t *src, const size_t len, const uint8_t blockSize){
 320         static uint8_t buf[64];
 321         memset(buf, 0x00, 64);
 322         uint8_t *tmp = buf;
 323         for (uint8_t block=0; block < (uint8_t)(len/blockSize); block++){
 324                 for (size_t i = 0; i < blockSize; i++){
 325                         tmp[i+(blockSize*block)] = src[(blockSize-1-i)+(blockSize*block)];
 326                 }
 327         }
 328         return tmp;
 329 }
 330
 331 //assumes little endian
 332 char * printBits(size_t const size, void const * const ptr)
 333 {
 334     unsigned char *b = (unsigned char*) ptr;
 335     unsigned char byte;
 336         static char buf[1024];
 337         char * tmp = buf;
 338     int i, j;
 339
 340     for (i=size-1;i>=0;i--)
 341     {
 342         for (j=7;j>=0;j--)
 343         {
 344             byte = b[i] & (1<<j);
 345             byte >>= j;
 346             sprintf(tmp, "%u", (unsigned int)byte);
 347                         tmp++;
 348         }
 349     }
 350         return buf;
 351 }
 352
 353 char * printBitsPar(const uint8_t *b, size_t len) {
 354         static char buf1[512] = {0};
 355         static char buf2[512] = {0};
 356         static char *buf;
 357         if (buf != buf1)
 358                 buf = buf1;
 359         else
 360                 buf = buf2;
 361         memset(buf, 0x00, 512);
 362
 363         for (int i = 0; i < len; i++) {
 364                 buf[i] = ((b[i / 8] << (i % 8)) & 0x80) ? '1':'0';
 365         }
 366         return buf;
 367 }
 368
 369
 370 //  -------------------------------------------------------------------------
 371 //  string parameters lib
 372 //  -------------------------------------------------------------------------
 373
 374 //  -------------------------------------------------------------------------
 375 //  line     - param line
 376 //  bg, en   - symbol numbers in param line of beginning and ending parameter
 377 //  paramnum - param number (from 0)
 378 //  -------------------------------------------------------------------------
 379 int param_getptr(const char *line, int *bg, int *en, int paramnum)
 380 {
 381         int i;
 382         int len = strlen(line);
 383
 384         *bg = 0;
 385         *en = 0;
 386
 387   // skip spaces
 388         while (line[*bg] ==' ' || line[*bg]=='\t') (*bg)++;
 389         if (*bg >= len) {
 390                 return 1;
 391         }
 392
 393         for (i = 0; i < paramnum; i++) {
 394                 while (line[*bg]!=' ' && line[*bg]!='\t' && line[*bg] != '\0') (*bg)++;
 395                 while (line[*bg]==' ' || line[*bg]=='\t') (*bg)++;
 396
 397                 if (line[*bg] == '\0') return 1;
 398         }
 399
 400         *en = *bg;
 401         while (line[*en] != ' ' && line[*en] != '\t' && line[*en] != '\0') (*en)++;
 402
 403         (*en)--;
 404
 405         return 0;
 406 }
 407
 408
 409 int param_getlength(const char *line, int paramnum)
 410 {
 411         int bg, en;
 412
 413         if (param_getptr(line, &bg, &en, paramnum)) return 0;
 414
 415         return en - bg + 1;
 416 }
 417
 418 char param_getchar(const char *line, int paramnum) {
 419         return param_getchar_indx(line, 0, paramnum);
 420 }
 421
 422 char param_getchar_indx(const char *line, int indx, int paramnum) {
 423         int bg, en;
 424
 425         if (param_getptr(line, &bg, &en, paramnum)) return 0x00;
 426
 427         if (bg + indx > en)
 428                 return '\0';
 429
 430         return line[bg + indx];
 431 }
 432
 433 uint8_t param_get8(const char *line, int paramnum)
 434 {
 435         return param_get8ex(line, paramnum, 0, 10);
 436 }
 437
 438 /**
 439  * @brief Reads a decimal integer (actually, 0-254, not 255)
 440  * @param line
 441  * @param paramnum
 442  * @return -1 if error
 443  */
 444 uint8_t param_getdec(const char *line, int paramnum, uint8_t *destination)
 445 {
 446         uint8_t val =  param_get8ex(line, paramnum, 255, 10);
 447         if( (int8_t) val == -1) return 1;
 448         (*destination) = val;
 449         return 0;
 450 }
 451 /**
 452  * @brief Checks if param is decimal
 453  * @param line
 454  * @param paramnum
 455  * @return
 456  */
 457 uint8_t param_isdec(const char *line, int paramnum)
 458 {
 459         int bg, en;
 460         //TODO, check more thorougly
 461         if (!param_getptr(line, &bg, &en, paramnum)) return 1;
 462                 //              return strtoul(&line[bg], NULL, 10) & 0xff;
 463
 464         return 0;
 465 }
 466
 467 uint8_t param_get8ex(const char *line, int paramnum, int deflt, int base)
 468 {
 469         int bg, en;
 470
 471         if (!param_getptr(line, &bg, &en, paramnum))
 472                 return strtoul(&line[bg], NULL, base) & 0xff;
 473         else
 474                 return deflt;
 475 }
 476
 477 uint32_t param_get32ex(const char *line, int paramnum, int deflt, int base)
 478 {
 479         int bg, en;
 480
 481         if (!param_getptr(line, &bg, &en, paramnum))
 482                 return strtoul(&line[bg], NULL, base);
 483         else
 484                 return deflt;
 485 }
 486
 487 uint64_t param_get64ex(const char *line, int paramnum, int deflt, int base)
 488 {
 489         int bg, en;
 490
 491         if (!param_getptr(line, &bg, &en, paramnum))
 492                 return strtoull(&line[bg], NULL, base);
 493         else
 494                 return deflt;
 495 }
 496
 497 int param_gethex(const char *line, int paramnum, uint8_t * data, int hexcnt)
 498 {
 499         int bg, en, temp, i;
 500
 501         if (hexcnt % 2)
 502                 return 1;
 503
 504         if (param_getptr(line, &bg, &en, paramnum)) return 1;
 505
 506         if (en - bg + 1 != hexcnt)
 507                 return 1;
 508
 509         for(i = 0; i < hexcnt; i += 2) {
 510                 if (!(isxdigit((unsigned char)line[bg + i]) && isxdigit((unsigned char)line[bg + i + 1])) )     return 1;
 511
 512                 sscanf((char[]){line[bg + i], line[bg + i + 1], 0}, "%X", &temp);
 513                 data[i / 2] = temp & 0xff;
 514         }
 515
 516         return 0;
 517 }
 518 int param_gethex_ex(const char *line, int paramnum, uint8_t * data, int *hexcnt)
 519 {
 520         int bg, en, temp, i;
 521
 522         //if (hexcnt % 2)
 523         //      return 1;
 524
 525         if (param_getptr(line, &bg, &en, paramnum)) return 1;
 526
 527         *hexcnt = en - bg + 1;
 528         if (*hexcnt % 2) //error if not complete hex bytes
 529                 return 1;
 530
 531         for(i = 0; i < *hexcnt; i += 2) {
 532                 if (!(isxdigit((unsigned char)line[bg + i]) && isxdigit((unsigned char)line[bg + i + 1])) )     return 1;
 533
 534                 sscanf((char[]){line[bg + i], line[bg + i + 1], 0}, "%X", &temp);
 535                 data[i / 2] = temp & 0xff;
 536         }
 537
 538         return 0;
 539 }
 540
 541 int param_gethex_to_eol(const char *line, int paramnum, uint8_t * data, int maxdatalen, int *datalen) {
 542         int bg, en;
 543         uint32_t temp;
 544         char buf[5] = {0};
 545
 546         if (param_getptr(line, &bg, &en, paramnum)) return 1;
 547
 548         *datalen = 0;
 549
 550         int indx = bg;
 551         while (line[indx]) {
 552                 if (line[indx] == '\t' || line[indx] == ' ') {
 553                         indx++;
 554                         continue;
 555                 }
 556
 557                 if (isxdigit((unsigned char)line[indx])) {
 558                         buf[strlen(buf) + 1] = 0x00;
 559                         buf[strlen(buf)] = line[indx];
 560                 } else {
 561                         // if we have symbols other than spaces and hex
 562                         return 1;
 563                 }
 564
 565                 if (*datalen >= maxdatalen) {
 566                         // if we dont have space in buffer and have symbols to translate
 567                         return 2;
 568                 }
 569
 570                 if (strlen(buf) >= 2) {
 571                         sscanf(buf, "%x", &temp);
 572                         data[*datalen] = (uint8_t)(temp & 0xff);
 573                         *buf = 0;
 574                         (*datalen)++;
 575                 }
 576
 577                 indx++;
 578         }
 579
 580         if (strlen(buf) > 0)
 581                 //error when not completed hex bytes
 582                 return 3;
 583
 584         return 0;
 585 }
 586
 587 int param_getstr(const char *line, int paramnum, char * str, size_t buffersize)
 588 {
 589         int bg, en;
 590
 591         if (param_getptr(line, &bg, &en, paramnum)) {
 592                 return 0;
 593         }
 594
 595         // Prevent out of bounds errors
 596         if (en - bg + 1 >= buffersize) {
 597                 printf("out of bounds error: want %d bytes have %zd bytes\n", en - bg + 1 + 1, buffersize);
 598                 return 0;
 599         }
 600
 601         memcpy(str, line + bg, en - bg + 1);
 602         str[en - bg + 1] = 0;
 603
 604         return en - bg + 1;
 605 }
 606
 607 /*
 608 The following methods comes from Rfidler sourcecode.
 609 https://github.com/ApertureLabsLtd/RFIDler/blob/master/firmware/Pic32/RFIDler.X/src/
 610 */
 611
 612 // convert hex to sequence of 0/1 bit values
 613 // returns number of bits converted
 614 int hextobinarray(char *target, char *source)
 615 {
 616     int length, i, count= 0;
 617     char* start = source;
 618     char x;
 619
 620     length = strlen(source);
 621     // process 4 bits (1 hex digit) at a time
 622     while(length--)
 623     {
 624         x= *(source++);
 625         // capitalize
 626         if (x >= 'a' && x <= 'f')
 627             x -= 32;
 628         // convert to numeric value
 629         if (x >= '0' && x <= '9')
 630             x -= '0';
 631         else if (x >= 'A' && x <= 'F')
 632             x -= 'A' - 10;
 633         else {
 634                 printf("Discovered unknown character %c %d at idx %tu of %s\n", x, x, source - start, start);
 635             return 0;
 636         }
 637         // output
 638         for(i= 0 ; i < 4 ; ++i, ++count)
 639             *(target++)= (x >> (3 - i)) & 1;
 640     }
 641
 642     return count;
 643 }
 644
 645 // convert binary array of 0x00/0x01 values to hex (safe to do in place as target will always be shorter than source)
 646 // return number of bits converted
 647 int binarraytohex(char *target,char *source, int length)
 648 {
 649     unsigned char i, x;
 650     int j = length;
 651
 652     if(j % 4)
 653         return 0;
 654
 655     while(j)
 656     {
 657         for(i= x= 0 ; i < 4 ; ++i)
 658             x +=  ( source[i] << (3 - i));
 659         sprintf(target,"%X", (unsigned int)x);
 660         ++target;
 661         source += 4;
 662         j -= 4;
 663     }
 664     return length;
 665 }
 666
 667 // return parity bit required to match type
 668 uint8_t GetParity( uint8_t *bits, uint8_t type, int length)
 669 {
 670     int x;
 671
 672     for(x= 0 ; length > 0 ; --length)
 673         x += bits[length - 1];
 674     x %= 2;
 675
 676     return x ^ type;
 677 }
 678
 679 // add HID parity to binary array: EVEN prefix for 1st half of ID, ODD suffix for 2nd half
 680 void wiegand_add_parity(uint8_t *target, uint8_t *source, uint8_t length)
 681 {
 682     *(target++)= GetParity(source, EVEN, length / 2);
 683     memcpy(target, source, length);
 684     target += length;
 685     *(target)= GetParity(source + length / 2, ODD, length / 2);
 686 }
 687
 688 // xor two arrays together for len items.  The dst array contains the new xored values.
 689 void xor(unsigned char *dst, unsigned char *src, size_t len) {
 690    for( ; len > 0; len--,dst++,src++)
 691        *dst ^= *src;
 692 }
 693
 694 // RotateLeft - Ultralight, Desfire, works on byte level
 695 // 00-01-02  >> 01-02-00
 696 void rol(uint8_t *data, const size_t len){
 697     uint8_t first = data[0];
 698     for (size_t i = 0; i < len-1; i++) {
 699         data[i] = data[i+1];
 700     }
 701     data[len-1] = first;
 702 }
 703
 704
 705 // Replace unprintable characters with a dot in char buffer
 706 void clean_ascii(unsigned char *buf, size_t len) {
 707   for (size_t i = 0; i < len; i++) {
 708     if (!isprint(buf[i]))
 709       buf[i] = '.';
 710   }
 711 }
 712
 713 // replace \r \n to \0
 714 void strcleanrn(char *buf, size_t len) {
 715         strcreplace(buf, len, '\n', '\0');
 716         strcreplace(buf, len, '\r', '\0');
 717 }
 718
 719 // replace char in buffer
 720 void strcreplace(char *buf, size_t len, char from, char to) {
 721   for (size_t i = 0; i < len; i++) {
 722     if (buf[i] == from)
 723       buf[i] = to;
 724   }
 725 }
 726
 727 char *strmcopy(char *buf) {
 728         char * str = NULL;
 729         if ((str = (char*) malloc(strlen(buf) + 1)) != NULL) {
 730                 memset(str, 0, strlen(buf) + 1);
 731                 strcpy(str, buf);
 732         }
 733         return str;
 734 }
 735
 736
 737 // determine number of logical CPU cores (use for multithreaded functions)
 738 extern int num_CPUs(void)
 739 {
 740 #if defined(_WIN32)
 741         #include <sysinfoapi.h>
 742         SYSTEM_INFO sysinfo;
 743         GetSystemInfo(&sysinfo);
 744         return sysinfo.dwNumberOfProcessors;
 745 #elif defined(__linux__) || defined(__APPLE__)
 746         #include <unistd.h>
 747         return sysconf(_SC_NPROCESSORS_ONLN);
 748 #else
 749         return 1;
 750 #endif
 751 }
 752