git.zerfleddert.de Git - proxmark3-svn/blob - armsrc/string.c

   1 //-----------------------------------------------------------------------------
   2 // Jonathan Westhues, Sept 2005
   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 // Common string.h functions
   9 //-----------------------------------------------------------------------------
  10 #include "string.h"
  11
  12 void *memcpy(void *dest, const void *src, int len)
  13 {
  14         uint8_t *d = dest;
  15         const uint8_t *s = src;
  16         while((len--) > 0) {
  17                 *d = *s;
  18                 d++;
  19                 s++;
  20         }
  21         return dest;
  22 }
  23
  24 void *memset(void *dest, int c, int len)
  25 {
  26         uint8_t *d = dest;
  27         while((len--) > 0) {
  28                 *d = c;
  29                 d++;
  30         }
  31         return dest;
  32 }
  33
  34 int memcmp(const void *av, const void *bv, int len)
  35 {
  36         const uint8_t *a = av;
  37         const uint8_t *b = bv;
  38
  39         while((len--) > 0) {
  40                 if(*a != *b) {
  41                         return *a - *b;
  42                 }
  43                 a++;
  44                 b++;
  45         }
  46         return 0;
  47 }
  48
  49 void memxor(uint8_t * dest, uint8_t * src, size_t len) {
  50    for( ; len > 0; len--,dest++,src++)
  51        *dest ^= *src;
  52 }
  53
  54 int strlen(const char *str)
  55 {
  56         int l = 0;
  57         while(*str) {
  58                 l++;
  59                 str++;
  60         }
  61         return l;
  62 }
  63
  64 char* strncat(char *dest, const char *src, unsigned int n)
  65 {
  66         unsigned int dest_len = strlen(dest);
  67         unsigned int i;
  68
  69         for (i = 0 ; i < n && src[i] != '\0' ; i++)
  70                 dest[dest_len + i] = src[i];
  71         dest[dest_len + i] = '\0';
  72
  73         return dest;
  74 }
  75
  76 char* strcat(char *dest, const char *src)
  77 {
  78         unsigned int dest_len = strlen(dest);
  79         unsigned int i;
  80
  81         for (i = 0 ; src[i] != '\0' ; i++)
  82                 dest[dest_len + i] = src[i];
  83         dest[dest_len + i] = '\0';
  84
  85         return dest;
  86 }
  87 ////////////////////////////////////////// code to do 'itoa'
  88
  89 /* reverse:  reverse string s in place */
  90 void strreverse(char s[])
  91 {
  92     int c, i, j;
  93
  94     for (i = 0, j = strlen(s)-1; i<j; i++, j--) {
  95         c = s[i];
  96         s[i] = s[j];
  97         s[j] = c;
  98     }
  99 }
 100
 101 /* itoa:  convert n to characters in s */
 102 void itoa(int n, char s[])
 103 {
 104     int i, sign;
 105
 106     if ((sign = n) < 0)  /* record sign */
 107         n = -n;          /* make n positive */
 108     i = 0;
 109     do {       /* generate digits in reverse order */
 110         s[i++] = n % 10 + '0';   /* get next digit */
 111     } while ((n /= 10) > 0);     /* delete it */
 112     if (sign < 0)
 113         s[i++] = '-';
 114     s[i] = '\0';
 115     strreverse(s);
 116 }
 117
 118 //////////////////////////////////////// END 'itoa' CODE