2 * This file is part of the libpayload project.
4 * Copyright (C) 2007 Uwe Hermann <uwe@hermann-uwe.de>
5 * Copyright (C) 2008 Advanced Micro Devices, Inc.
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. The name of the author may not be used to endorse or promote products
16 * derived from this software without specific prior written permission.
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 #include <libpayload.h>
34 * Calculate the length of a fixed-size string.
36 * @param str The input string.
37 * @param maxlen Return at most maxlen characters as length of the string.
38 * @return The length of the string, not including the final NUL character.
39 * The maximum length returned is maxlen.
41 size_t strnlen(const char *str, size_t maxlen)
45 /* NULL and empty strings have length 0. */
49 /* Loop until we find a NUL character, or maxlen is reached. */
50 while ((*str++ != '\0') && (len < maxlen))
57 * Calculate the length of a string.
59 * @param str The input string.
60 * @return The length of the string, not including the final NUL character.
62 size_t strlen(const char *str)
66 /* NULL and empty strings have length 0. */
70 /* Loop until we find a NUL character. */
71 while (*str++ != '\0')
78 * Compare two strings.
80 * @param s1 The first string.
81 * @param s2 The second string.
82 * @return Returns a value less than zero, if s1 is shorter than s2. Returns
83 * zero, if s1 equals s2. Returns a value greater than zero, if
84 * s1 is longer than s2.
86 int strcmp(const char *s1, const char *s2)
90 /* Set c1 == c2, so that we can enter the while loop. */
94 /* Compare characters until they differ, or one of the strings ends. */
96 /* Read the next character from each string. */
100 /* Return something negative (if s1 is shorter than s2), or
101 zero (if s1 equals s2). */
106 /* Return something positive (if s1 is longer than s2), or zero (if s1
107 and s2 are equal). */
112 * Compare two strings with fixed length.
114 * @param s1 The first string.
115 * @param s2 The second string.
116 * @param maxlen Return at most maxlen characters as length of the string.
117 * @return A non-zero value if s1 and s2 differ, or zero if s1 equals s2.
119 int strncmp(const char *s1, const char *s2, size_t maxlen)
123 for (i = 0; i < maxlen; i++) {
125 return s1[i] - s2[i];
132 * Copy a string with a maximum length.
134 * @param d The destination memory.
135 * @param s The source string.
136 * @param n Copy at most n characters as length of the string.
137 * @return A pointer to the destination memory.
139 char *strncpy(char *d, const char *s, size_t n)
141 /* Use +1 to get the NUL terminator. */
142 int max = n > strlen(s) + 1 ? strlen(s) + 1 : n;
145 for (i = 0; i < max; i++)
154 * @param d The destination memory.
155 * @param s The source string.
156 * @return A pointer to the destination memory.
158 char *strcpy(char *d, const char *s)
160 return strncpy(d, s, strlen(s) + 1);
164 * Concatenates two strings with a maximum length.
166 * @param d The destination string.
167 * @param s The source string.
168 * @param n The target string will have a length of n characters at most.
169 * @return A pointer to the destination string.
171 char *strncat(char *d, const char *s, size_t n)
173 char *p = d + strlen(d);
174 int max = n > strlen(s) ? strlen(s) : n;
177 for (i = 0; i < max; i++)
185 * Find a character in a string.
187 * @param s The string.
188 * @param c The character.
189 * @return A pointer to the first occurence of the character in the
190 * string, or NULL if the character was not encountered within the string.
192 char *strchr(const char *s, int c)
196 for (; *p != 0; p++) {
205 * Duplicate a string.
207 * @param s The string to duplicate.
208 * @return A pointer to the copy of the original string.
210 char *strdup(const char *s)
213 char *p = malloc(n + 1);
223 * Find a substring within a string.
225 * @param h The haystack string.
226 * @param n The needle string (substring).
227 * @return A pointer to the first occurence of the substring in
228 * the string, or NULL if the substring was not encountered within the string.
230 char *strstr(const char *h, const char *n)
236 for (i = 0; i <= hn - nn; i++)
237 if (!strcmp(&h[i], n))
238 return (char *)&h[i];
246 * @param stringp reference of the string to separate.
247 * @param delim string containing all delimiters.
248 * @return Token string.
250 char *strsep(char **stringp, const char *delim)
254 if (!stringp || !*stringp || !**stringp)
257 token = walk = *stringp;
259 /* Walk, search for delimiters */
260 while(*walk && !strchr(delim, *walk))