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  1. /*
  2.  * Copyright (c) 2001-2004 Jakub Jermar
  3.  * All rights reserved.
  4.  *
  5.  * Redistribution and use in source and binary forms, with or without
  6.  * modification, are permitted provided that the following conditions
  7.  * are met:
  8.  *
  9.  * - Redistributions of source code must retain the above copyright
  10.  *   notice, this list of conditions and the following disclaimer.
  11.  * - Redistributions in binary form must reproduce the above copyright
  12.  *   notice, this list of conditions and the following disclaimer in the
  13.  *   documentation and/or other materials provided with the distribution.
  14.  * - The name of the author may not be used to endorse or promote products
  15.  *   derived from this software without specific prior written permission.
  16.  *
  17.  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  18.  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  19.  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  20.  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  21.  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  22.  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  23.  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  24.  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  25.  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  26.  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27.  */
  28.  
  29. /** @addtogroup generic
  30.  * @{
  31.  */
  32.  
  33. #include <string.h>
  34.  
  35. /**
  36.  * @file
  37.  * @brief   String manipulation functions.
  38.  */
  39.  
  40. /** Return number of characters in a string.
  41.  *
  42.  * @param str NULL terminated string.
  43.  *
  44.  * @return Number of characters in str.
  45.  */
  46. size_t strlen(const char *str)
  47. {
  48.     int i;
  49.    
  50.     for (i = 0; str[i]; i++)
  51.         ;
  52.    
  53.     return i;
  54. }
  55.  
  56. /** Compare two NULL terminated strings
  57.  *
  58.  * Do a char-by-char comparison of two NULL terminated strings.
  59.  * The strings are considered equal iff they consist of the same
  60.  * characters on the minimum of their lengths.
  61.  *
  62.  * @param src First string to compare.
  63.  * @param dst Second string to compare.
  64.  *
  65.  * @return 0 if the strings are equal, -1 if first is smaller, 1 if second smaller.
  66.  *
  67.  */
  68. int strcmp(const char *src, const char *dst)
  69. {
  70.     for (; *src && *dst; src++, dst++) {
  71.         if (*src < *dst)
  72.             return -1;
  73.         if (*src > *dst)
  74.             return 1;
  75.     }
  76.     if (*src == *dst)
  77.         return 0;
  78.     if (!*src)
  79.         return -1;
  80.     return 1;
  81. }
  82.  
  83.  
  84. /** Compare two NULL terminated strings
  85.  *
  86.  * Do a char-by-char comparison of two NULL terminated strings.
  87.  * The strings are considered equal iff they consist of the same
  88.  * characters on the minimum of their lengths and specified maximal
  89.  * length.
  90.  *
  91.  * @param src First string to compare.
  92.  * @param dst Second string to compare.
  93.  * @param len Maximal length for comparison.
  94.  *
  95.  * @return 0 if the strings are equal, -1 if first is smaller, 1 if second smaller.
  96.  *
  97.  */
  98. int strncmp(const char *src, const char *dst, size_t len)
  99. {
  100.     int i;
  101.    
  102.     for (i = 0; *src && *dst && i < len; src++, dst++, i++) {
  103.         if (*src < *dst)
  104.             return -1;
  105.         if (*src > *dst)
  106.             return 1;
  107.     }
  108.     if (i == len || *src == *dst)
  109.         return 0;
  110.     if (!*src)
  111.         return -1;
  112.     return 1;
  113. }
  114.  
  115. /** Copy NULL terminated string.
  116.  *
  117.  * Copy at most 'len' characters from string 'src' to 'dest'.
  118.  * If 'src' is shorter than 'len', '\0' is inserted behind the
  119.  * last copied character.
  120.  *
  121.  * @param src Source string.
  122.  * @param dest Destination buffer.
  123.  * @param len Size of destination buffer.
  124.  */
  125. void strncpy(char *dest, const char *src, size_t len)
  126. {
  127.     int i;
  128.     for (i = 0; i < len; i++) {
  129.         if (!(dest[i] = src[i]))
  130.             return;
  131.     }
  132.     dest[i-1] = '\0';
  133. }
  134.  
  135. /** Convert ascii representation to unative_t
  136.  *
  137.  * Supports 0x for hexa & 0 for octal notation.
  138.  * Does not check for overflows, does not support negative numbers
  139.  *
  140.  * @param text Textual representation of number
  141.  * @return Converted number or 0 if no valid number ofund
  142.  */
  143. unative_t atoi(const char *text)
  144. {
  145.     int base = 10;
  146.     unative_t result = 0;
  147.  
  148.     if (text[0] == '0' && text[1] == 'x') {
  149.         base = 16;
  150.         text += 2;
  151.     } else if (text[0] == '0')
  152.         base = 8;
  153.  
  154.     while (*text) {
  155.         if (base != 16 && \
  156.             ((*text >= 'A' && *text <= 'F' )
  157.              || (*text >='a' && *text <='f')))
  158.             break;
  159.         if (base == 8 && *text >='8')
  160.             break;
  161.  
  162.         if (*text >= '0' && *text <= '9') {
  163.             result *= base;
  164.             result += *text - '0';
  165.         } else if (*text >= 'A' && *text <= 'F') {
  166.             result *= base;
  167.             result += *text - 'A' + 10;
  168.         } else if (*text >= 'a' && *text <= 'f') {
  169.             result *= base;
  170.             result += *text - 'a' + 10;
  171.         } else
  172.             break;
  173.         text++;
  174.     }
  175.  
  176.     return result;
  177. }
  178.  
  179. /** @}
  180.  */
  181.