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  */
24 
25 /*
26  * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
27  * All rights reserved.
28  *
29  * Redistribution and use in source and binary forms, with or without modification,
30  * are permitted provided that the following conditions are met:
31  *
32  * 1. Redistributions of source code must retain the above copyright notice,
33  *    this list of conditions and the following disclaimer.
34  * 2. Redistributions in binary form must reproduce the above copyright notice,
35  *    this list of conditions and the following disclaimer in the documentation
36  *    and/or other materials provided with the distribution.
37  * 3. The name of the author may not be used to endorse or promote products
38  *    derived from this software without specific prior written permission.
39  *
40  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
41  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
42  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
43  * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
44  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
45  * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
46  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
47  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
48  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
49  * OF SUCH DAMAGE.
50  *
51  * This file is part of the lwIP TCP/IP stack.
52  *
53  * Author: Simon Goldschmidt
54  *
55  */
56 
57 #include "lwip/opt.h"
58 #include "lwip/def.h"
59 #include "aos/kernel.h"
60 
61 
62 #include <string.h>
63 
64 #if BYTE_ORDER == LITTLE_ENDIAN
65 
66 #if !defined(lwip_htons)
67 /**
68  * Convert an u16_t from host- to network byte order.
69  *
70  * @param n u16_t in host byte order
71  * @return n in network byte order
72  */
73 u16_t
lwip_htons(u16_t n)74 lwip_htons(u16_t n)
75 {
76   return (u16_t)PP_HTONS(n);
77 }
78 
79 #endif /* lwip_htons */
80 
81 #if !defined(lwip_htonl)
82 /**
83  * Convert an u32_t from host- to network byte order.
84  *
85  * @param n u32_t in host byte order
86  * @return n in network byte order
87  */
88 u32_t
lwip_htonl(u32_t n)89 lwip_htonl(u32_t n)
90 {
91   return (u32_t)PP_HTONL(n);
92 }
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*
lwip_strnstr(const char * buffer,const char * token,size_t n)105 lwip_strnstr(const char* buffer, const char* token, size_t n)
106 {
107   const char* p;
108   int tokenlen = (int)strlen(token);
109   if (tokenlen == 0) {
110     return (char *)(size_t)buffer;
111   }
112   for (p = buffer; *p && (p + tokenlen <= buffer + n); p++) {
113     if ((*p == *token) && (strncmp(p, token, tokenlen) == 0)) {
114       return (char *)(size_t)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
lwip_stricmp(const char * str1,const char * str2)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
lwip_strnicmp(const char * str1,const char * str2,size_t len)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
lwip_itoa(char * result,size_t bufsize,int number)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
223