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
lwip_htons(u16_t n)76 lwip_htons(u16_t n)
77 {
78 return 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
lwip_htonl(u32_t n)90 lwip_htonl(u32_t n)
91 {
92 return 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 *
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 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
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 len--;
187 } while ((len != 0) && (c1 != 0));
188 return 0;
189 }
190 #endif
191
192 #ifndef lwip_itoa
193 /**
194 * @ingroup sys_nonstandard
195 * lwIP default implementation for itoa() non-standard function.
196 * This can be \#defined to itoa() or snprintf(result, bufsize, "%d", number) depending on your platform port.
197 */
198 void
lwip_itoa(char * result,size_t bufsize,int number)199 lwip_itoa(char *result, size_t bufsize, int number)
200 {
201 char *res = result;
202 char *tmp = result + bufsize - 1;
203 int n = (number >= 0) ? number : -number;
204
205 /* handle invalid bufsize */
206 if (bufsize < 2) {
207 if (bufsize == 1) {
208 *result = 0;
209 }
210 return;
211 }
212
213 /* First, add sign */
214 if (number < 0) {
215 *res++ = '-';
216 }
217 /* Then create the string from the end and stop if buffer full,
218 and ensure output string is zero terminated */
219 *tmp = 0;
220 while ((n != 0) && (tmp > res)) {
221 char val = (char)('0' + (n % 10));
222 tmp--;
223 *tmp = val;
224 n = n / 10;
225 }
226 if (n) {
227 /* buffer is too small */
228 *result = 0;
229 return;
230 }
231 if (*tmp == 0) {
232 /* Nothing added? */
233 *res++ = '0';
234 *res++ = 0;
235 return;
236 }
237 /* move from temporary buffer to output buffer (sign is not moved) */
238 memmove(res, tmp, (size_t)((result + bufsize) - tmp));
239 }
240 #endif
241