Subversion Repositories HelenOS

Rev

Rev 3022 | Blame | Compare with Previous | Last modification | View Log | Download | RSS feed

  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,
  66.  *          1 if second smaller.
  67.  *
  68.  */
  69. int strcmp(const char *src, const char *dst)
  70. {
  71.     for (; *src && *dst; src++, dst++) {
  72.         if (*src < *dst)
  73.             return -1;
  74.         if (*src > *dst)
  75.             return 1;
  76.     }
  77.     if (*src == *dst)
  78.         return 0;
  79.     if (!*src)
  80.         return -1;
  81.     return 1;
  82. }
  83.  
  84.  
  85. /** Compare two NULL terminated strings.
  86.  *
  87.  * Do a char-by-char comparison of two NULL terminated strings.
  88.  * The strings are considered equal iff they consist of the same
  89.  * characters on the minimum of their lengths and specified maximal
  90.  * length.
  91.  *
  92.  * @param src       First string to compare.
  93.  * @param dst       Second string to compare.
  94.  * @param len       Maximal length for comparison.
  95.  *
  96.  * @return      0 if the strings are equal, -1 if first is smaller,
  97.  *          1 if second smaller.
  98.  *
  99.  */
  100. int strncmp(const char *src, const char *dst, size_t len)
  101. {
  102.     int i;
  103.    
  104.     for (i = 0; *src && *dst && i < len; src++, dst++, i++) {
  105.         if (*src < *dst)
  106.             return -1;
  107.         if (*src > *dst)
  108.             return 1;
  109.     }
  110.     if (i == len || *src == *dst)
  111.         return 0;
  112.     if (!*src)
  113.         return -1;
  114.     return 1;
  115. }
  116.  
  117. /** Copy NULL terminated string.
  118.  *
  119.  * Copy at most 'len' characters from string 'src' to 'dest'.
  120.  * If 'src' is shorter than 'len', '\0' is inserted behind the
  121.  * last copied character.
  122.  *
  123.  * @param src       Source string.
  124.  * @param dest      Destination buffer.
  125.  * @param len       Size of destination buffer.
  126.  */
  127. void strncpy(char *dest, const char *src, size_t len)
  128. {
  129.     int i;
  130.     for (i = 0; i < len; i++) {
  131.         if (!(dest[i] = src[i]))
  132.             return;
  133.     }
  134.     dest[i-1] = '\0';
  135. }
  136.  
  137. /** Convert ascii representation to unative_t.
  138.  *
  139.  * Supports 0x for hexa & 0 for octal notation.
  140.  * Does not check for overflows, does not support negative numbers
  141.  *
  142.  * @param text      Textual representation of number.
  143.  * @return      Converted number or 0 if no valid number found.
  144.  */
  145. unative_t atoi(const char *text)
  146. {
  147.     int base = 10;
  148.     unative_t result = 0;
  149.  
  150.     if (text[0] == '0' && text[1] == 'x') {
  151.         base = 16;
  152.         text += 2;
  153.     } else if (text[0] == '0')
  154.         base = 8;
  155.  
  156.     while (*text) {
  157.         if (base != 16 &&
  158.             ((*text >= 'A' && *text <= 'F') ||
  159.             (*text >='a' && *text <='f')))
  160.             break;
  161.         if (base == 8 && *text >='8')
  162.             break;
  163.  
  164.         if (*text >= '0' && *text <= '9') {
  165.             result *= base;
  166.             result += *text - '0';
  167.         } else if (*text >= 'A' && *text <= 'F') {
  168.             result *= base;
  169.             result += *text - 'A' + 10;
  170.         } else if (*text >= 'a' && *text <= 'f') {
  171.             result *= base;
  172.             result += *text - 'a' + 10;
  173.         } else
  174.             break;
  175.         text++;
  176.     }
  177.  
  178.     return result;
  179. }
  180.  
  181. /** Move piece of memory to another, possibly overlapping, location.
  182.  *
  183.  * @param dst       Destination address.
  184.  * @param src       Source address.
  185.  * @param len       Number of bytes to move.
  186.  *
  187.  * @return      Destination address.
  188.  */
  189. void *memmove(void *dst, const void *src, size_t len)
  190. {
  191.     char *d = dst;
  192.     const char *s = src;
  193.     if (s < d) {
  194.         while (len--)
  195.             *(d + len) = *(s + len);
  196.     } else {
  197.         while (len--)
  198.             *d++ = *s++;
  199.     }
  200.    
  201.     return dst;
  202. }
  203.  
  204. /** @}
  205.  */
  206.