text: /****************************************************************************
   *
   * Copyright 2016 Samsung Electronics All Rights Reserved.
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   * http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing,
   * software distributed under the License is distributed on an
   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
   * either express or implied. See the License for the specific
   * language governing permissions and limitations under the License.
   *
   ****************************************************************************/
  /*
   * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
   * All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without modification,
   * are permitted provided that the following conditions are met:
   *
   * 1. Redistributions of source code must retain the above copyright notice,
   *    this list of conditions and the following disclaimer.
   * 2. Redistributions in binary form must reproduce the above copyright notice,
   *    this list of conditions and the following disclaimer in the documentation
   *    and/or other materials provided with the distribution.
   * 3. The name of the author may not be used to endorse or promote products
   *    derived from this software without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
   * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
   * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
   * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
   * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
   * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
   * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
   * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
   * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
   * OF SUCH DAMAGE.
   *
   * This file is part of the lwIP TCP/IP stack.
   *
   * Author: Simon Goldschmidt
   *
   */
  
  /**
   * @file
   * Common functions used throughout the stack.
   *
   */
  
  #include "lwip/opt.h"
  #include "lwip/def.h"
  
  #include <string.h>
  
  #if BYTE_ORDER == LITTLE_ENDIAN
  
  #if !defined(lwip_htons)
  /**
   * Convert an u16_t from host- to network byte order.
   *
   * @param n u16_t in host byte order
   * @return n in network byte order
   */
  u16_t lwip_htons(u16_t n)
  {
  	return (u16_t) PP_HTONS(n);
  }
  #endif							/* lwip_htons */
  
  #if !defined(lwip_htonl)
  /**
   * Convert an u32_t from host- to network byte order.
   *
   * @param n u32_t in host byte order
   * @return n in network byte order
   */
  u32_t lwip_htonl(u32_t n)
  {
  	return (u32_t) PP_HTONL(n);
  }
  #endif							/* lwip_htonl */
  
  #endif							/* BYTE_ORDER == LITTLE_ENDIAN */
  
  #ifndef lwip_strnstr
  /**
   * lwIP default implementation for strnstr() non-standard function.
   * This can be \#defined to strnstr() depending on your platform port.
   */
  char *lwip_strnstr(const char *buffer, const char *token, size_t n)
  {
  	const char *p;
  	size_t tokenlen = strlen(token);
  	if (tokenlen == 0) {
  		return LWIP_CONST_CAST(char *, buffer);
  	}
  	for (p = buffer; *p && (p + tokenlen <= buffer + n); p++) {
  		if ((*p == *token) && (strncmp(p, token, tokenlen) == 0)) {
  			return LWIP_CONST_CAST(char *, p);
  		}
  	}
  	return NULL;
  }
  #endif
  
  #ifndef lwip_stricmp
  /**
   * @ingroup sys_nonstandard
   * lwIP default implementation for stricmp() non-standard function.
   * This can be \#defined to stricmp() depending on your platform port.
   */
  int lwip_stricmp(const char *str1, const char *str2)
  {
  	char c1, c2;
  
  	do {
  		c1 = *str1++;
  		c2 = *str2++;
  		if (c1 != c2) {
  			char c1_upc = c1 | 0x20;
  			if ((c1_upc >= 'a') && (c1_upc <= 'z')) {
  				/* characters are not equal an one is in the alphabet range:
  				   downcase both chars and check again */
  				char c2_upc = c2 | 0x20;
  				if (c1_upc != c2_upc) {
  					/* still not equal */
  					/* don't care for < or > */
  					return 1;
  				}
  			} else {
  				/* characters are not equal but none is in the alphabet range */
  				return 1;
  			}
  		}
  	} while (c1 != 0);
  	return 0;
  }
  #endif
  
  #ifndef lwip_strnicmp
  /**
   * lwIP default implementation for strnicmp() non-standard function.
   * This can be \#defined to strnicmp() depending on your platform port.
   */
  int lwip_strnicmp(const char *str1, const char *str2, size_t len)
  {
  	char c1, c2;
  
  	do {
  		c1 = *str1++;
  		c2 = *str2++;
  		if (c1 != c2) {
  			char c1_upc = c1 | 0x20;
  			if ((c1_upc >= 'a') && (c1_upc <= 'z')) {
  				/* characters are not equal an one is in the alphabet range:
  				   downcase both chars and check again */
  				char c2_upc = c2 | 0x20;
  				if (c1_upc != c2_upc) {
  					/* still not equal */
  					/* don't care for < or > */
  					return 1;
  				}
  			} else {
  				/* characters are not equal but none is in the alphabet range */
  				return 1;
  			}
  		}
  	} while (len-- && c1 != 0);
  	return 0;
  }
  #endif
  
  #ifndef lwip_itoa
  /**
   * lwIP default implementation for itoa() non-standard function.
   * This can be \#defined to itoa() or snprintf(result, bufsize, "%d", number) depending on your platform port.
   */
  void lwip_itoa(char *result, size_t bufsize, int number)
  {
  	const int base = 10;
  	char *ptr = result, *ptr1 = result, tmp_char;
  	int tmp_value;
  	LWIP_UNUSED_ARG(bufsize);
  
  	do {
  		tmp_value = number;
  		number /= base;
  		*ptr++ = "zyxwvutsrqponmlkjihgfedcba9876543210123456789abcdefghijklmnopqrstuvwxyz"[35 + (tmp_value - number * base)];
  	} while (number);
  
  	/* Apply negative sign */
  	if (tmp_value < 0) {
  		*ptr++ = '-';
  	}
  	*ptr-- = '\0';
  	while (ptr1 < ptr) {
  		tmp_char = *ptr;
  		*ptr-- = *ptr1;
  		*ptr1++ = tmp_char;
  	}
  }
  #endif
  