minix/lib/liblwip/dist/src/core/def.c

   1 /**
   2  * @file
   3  * Common functions used throughout the stack.
   4  *
   5  * These are reference implementations of the byte swapping functions.
   6  * Again with the aim of being simple, correct and fully portable.
   7  * Byte swapping is the second thing you would want to optimize. You will
   8  * need to port it to your architecture and in your cc.h:
   9  *
  10  * \#define lwip_htons(x) your_htons
  11  * \#define lwip_htonl(x) your_htonl
  12  *
  13  * Note lwip_ntohs() and lwip_ntohl() are merely references to the htonx counterparts.
  14  *
  15  * If you \#define them to htons() and htonl(), you should
  16  * \#define LWIP_DONT_PROVIDE_BYTEORDER_FUNCTIONS to prevent lwIP from
  17  * defining htonx/ntohx compatibility macros.
  18
  19  * @defgroup sys_nonstandard Non-standard functions
  20  * @ingroup sys_layer
  21  * lwIP provides default implementations for non-standard functions.
  22  * These can be mapped to OS functions to reduce code footprint if desired.
  23  * All defines related to this section must not be placed in lwipopts.h,
  24  * but in arch/cc.h!
  25  * These options cannot be \#defined in lwipopts.h since they are not options
  26  * of lwIP itself, but options of the lwIP port to your system.
  27  */
  28
  29 /*
  30  * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
  31  * All rights reserved.
  32  *
  33  * Redistribution and use in source and binary forms, with or without modification,
  34  * are permitted provided that the following conditions are met:
  35  *
  36  * 1. Redistributions of source code must retain the above copyright notice,
  37  *    this list of conditions and the following disclaimer.
  38  * 2. Redistributions in binary form must reproduce the above copyright notice,
  39  *    this list of conditions and the following disclaimer in the documentation
  40  *    and/or other materials provided with the distribution.
  41  * 3. The name of the author may not be used to endorse or promote products
  42  *    derived from this software without specific prior written permission.
  43  *
  44  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
  45  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  46  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
  47  * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  48  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
  49  * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  50  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  51  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  52  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
  53  * OF SUCH DAMAGE.
  54  *
  55  * This file is part of the lwIP TCP/IP stack.
  56  *
  57  * Author: Simon Goldschmidt
  58  *
  59  */
  60
  61 #include "lwip/opt.h"
  62 #include "lwip/def.h"
  63
  64 #include <string.h>
  65
  66 #if BYTE_ORDER == LITTLE_ENDIAN
  67
  68 #if !defined(lwip_htons)
  69 /**
  70  * Convert an u16_t from host- to network byte order.
  71  *
  72  * @param n u16_t in host byte order
  73  * @return n in network byte order
  74  */
  75 u16_t
  76 lwip_htons(u16_t n)
  77 {
  78   return (u16_t)PP_HTONS(n);
  79 }
  80 #endif /* lwip_htons */
  81
  82 #if !defined(lwip_htonl)
  83 /**
  84  * Convert an u32_t from host- to network byte order.
  85  *
  86  * @param n u32_t in host byte order
  87  * @return n in network byte order
  88  */
  89 u32_t
  90 lwip_htonl(u32_t n)
  91 {
  92   return (u32_t)PP_HTONL(n);
  93 }
  94 #endif /* lwip_htonl */
  95
  96 #endif /* BYTE_ORDER == LITTLE_ENDIAN */
  97
  98 #ifndef lwip_strnstr
  99 /**
 100  * @ingroup sys_nonstandard
 101  * lwIP default implementation for strnstr() non-standard function.
 102  * This can be \#defined to strnstr() depending on your platform port.
 103  */
 104 char*
 105 lwip_strnstr(const char* buffer, const char* token, size_t n)
 106 {
 107   const char* p;
 108   size_t tokenlen = strlen(token);
 109   if (tokenlen == 0) {
 110     return LWIP_CONST_CAST(char *, buffer);
 111   }
 112   for (p = buffer; *p && (p + tokenlen <= buffer + n); p++) {
 113     if ((*p == *token) && (strncmp(p, token, tokenlen) == 0)) {
 114       return LWIP_CONST_CAST(char *, p);
 115     }
 116   }
 117   return NULL;
 118 }
 119 #endif
 120
 121 #ifndef lwip_stricmp
 122 /**
 123  * @ingroup sys_nonstandard
 124  * lwIP default implementation for stricmp() non-standard function.
 125  * This can be \#defined to stricmp() depending on your platform port.
 126  */
 127 int
 128 lwip_stricmp(const char* str1, const char* str2)
 129 {
 130   char c1, c2;
 131
 132   do {
 133     c1 = *str1++;
 134     c2 = *str2++;
 135     if (c1 != c2) {
 136       char c1_upc = c1 | 0x20;
 137       if ((c1_upc >= 'a') && (c1_upc <= 'z')) {
 138         /* characters are not equal an one is in the alphabet range:
 139         downcase both chars and check again */
 140         char c2_upc = c2 | 0x20;
 141         if (c1_upc != c2_upc) {
 142           /* still not equal */
 143           /* don't care for < or > */
 144           return 1;
 145         }
 146       } else {
 147         /* characters are not equal but none is in the alphabet range */
 148         return 1;
 149       }
 150     }
 151   } while (c1 != 0);
 152   return 0;
 153 }
 154 #endif
 155
 156 #ifndef lwip_strnicmp
 157 /**
 158  * @ingroup sys_nonstandard
 159  * lwIP default implementation for strnicmp() non-standard function.
 160  * This can be \#defined to strnicmp() depending on your platform port.
 161  */
 162 int
 163 lwip_strnicmp(const char* str1, const char* str2, size_t len)
 164 {
 165   char c1, c2;
 166
 167   do {
 168     c1 = *str1++;
 169     c2 = *str2++;
 170     if (c1 != c2) {
 171       char c1_upc = c1 | 0x20;
 172       if ((c1_upc >= 'a') && (c1_upc <= 'z')) {
 173         /* characters are not equal an one is in the alphabet range:
 174         downcase both chars and check again */
 175         char c2_upc = c2 | 0x20;
 176         if (c1_upc != c2_upc) {
 177           /* still not equal */
 178           /* don't care for < or > */
 179           return 1;
 180         }
 181       } else {
 182         /* characters are not equal but none is in the alphabet range */
 183         return 1;
 184       }
 185     }
 186   } while (len-- && c1 != 0);
 187   return 0;
 188 }
 189 #endif
 190
 191 #ifndef lwip_itoa
 192 /**
 193  * @ingroup sys_nonstandard
 194  * lwIP default implementation for itoa() non-standard function.
 195  * This can be \#defined to itoa() or snprintf(result, bufsize, "%d", number) depending on your platform port.
 196  */
 197 void
 198 lwip_itoa(char* result, size_t bufsize, int number)
 199 {
 200   const int base = 10;
 201   char* ptr = result, *ptr1 = result, tmp_char;
 202   int tmp_value;
 203   LWIP_UNUSED_ARG(bufsize);
 204
 205   do {
 206     tmp_value = number;
 207     number /= base;
 208     *ptr++ = "zyxwvutsrqponmlkjihgfedcba9876543210123456789abcdefghijklmnopqrstuvwxyz"[35 + (tmp_value - number * base)];
 209   } while(number);
 210
 211    /* Apply negative sign */
 212   if (tmp_value < 0) {
 213      *ptr++ = '-';
 214   }
 215   *ptr-- = '\0';
 216   while(ptr1 < ptr) {
 217     tmp_char = *ptr;
 218     *ptr--= *ptr1;
 219     *ptr1++ = tmp_char;
 220   }
 221 }
 222 #endif