/* * Copyright (c) 2001-2004 Jakub Jermar * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * - Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * - 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. * - 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. */ /** @addtogroup generic * @{ */ /** * @file * @brief Miscellaneous functions. */ #include #include #include #include #include #include /** Decode a single UTF-8 character from a NULL-terminated string. * * Decode a single UTF-8 character from a plain char NULL-terminated * string. Decoding starts at @index and this index is incremented * if the current UTF-8 string is encoded in more than a single byte. * * @param str Plain character NULL-terminated string. * @param index Index (counted in plain characters) where to start * the decoding. * * @return Decoded character in UTF-32 or '?' if the encoding is wrong. * */ wchar_t utf8_decode(const char *str, index_t *index) { uint8_t c1; /* First plain character from str */ uint8_t c2; /* Second plain character from str */ uint8_t c3; /* Third plain character from str */ uint8_t c4; /* Fourth plain character from str */ c1 = (uint8_t) str[*index]; if ((c1 & 0x80) == 0) { /* Plain ASCII (code points 0 .. 127) */ return (wchar_t) c1; } else if ((c1 & 0xe0) == 0xc0) { /* Code points 128 .. 2047 */ c2 = (uint8_t) str[*index + 1]; if ((c2 & 0xc0) == 0x80) { (*index)++; return ((wchar_t) ((c1 & 0x1f) << 6) | (c2 & 0x3f)); } else return ((wchar_t) '?'); } else if ((c1 & 0xf0) == 0xe0) { /* Code points 2048 .. 65535 */ c2 = (uint8_t) str[*index + 1]; if ((c2 & 0xc0) == 0x80) { (*index)++; c3 = (uint8_t) str[*index + 1]; if ((c3 & 0xc0) == 0x80) { (*index)++; return ((wchar_t) ((c1 & 0x0f) << 12) | ((c2 & 0x3f) << 6) | (c3 & 0x3f)); } else return ((wchar_t) '?'); } else return ((wchar_t) '?'); } else if ((c1 & 0xf8) == 0xf0) { /* Code points 65536 .. 1114111 */ c2 = (uint8_t) str[*index + 1]; if ((c2 & 0xc0) == 0x80) { (*index)++; c3 = (uint8_t) str[*index + 1]; if ((c3 & 0xc0) == 0x80) { (*index)++; c4 = (uint8_t) str[*index + 1]; if ((c4 & 0xc0) == 0x80) { (*index)++; return ((wchar_t) ((c1 & 0x07) << 18) | ((c2 & 0x3f) << 12) | ((c3 & 0x3f) << 6) | (c4 & 0x3f)); } else return ((wchar_t) '?'); } else return ((wchar_t) '?'); } else return ((wchar_t) '?'); } return ((wchar_t) '?'); } /** Return number of characters in a string. * * @param str NULL terminated string. * * @return Number of characters in str. * */ size_t strlen(const char *str) { int i; for (i = 0; str[i]; i++); return i; } /** Compare two NULL terminated strings * * Do a char-by-char comparison of two NULL terminated strings. * The strings are considered equal iff they consist of the same * characters on the minimum of their lengths. * * @param src First string to compare. * @param dst Second string to compare. * * @return 0 if the strings are equal, -1 if first is smaller, 1 if second smaller. * */ int strcmp(const char *src, const char *dst) { for (; *src && *dst; src++, dst++) { if (*src < *dst) return -1; if (*src > *dst) return 1; } if (*src == *dst) return 0; if (!*src) return -1; return 1; } /** Compare two NULL terminated strings * * Do a char-by-char comparison of two NULL terminated strings. * The strings are considered equal iff they consist of the same * characters on the minimum of their lengths and specified maximal * length. * * @param src First string to compare. * @param dst Second string to compare. * @param len Maximal length for comparison. * * @return 0 if the strings are equal, -1 if first is smaller, 1 if second smaller. * */ int strncmp(const char *src, const char *dst, size_t len) { unsigned int i; for (i = 0; (*src) && (*dst) && (i < len); src++, dst++, i++) { if (*src < *dst) return -1; if (*src > *dst) return 1; } if (i == len || *src == *dst) return 0; if (!*src) return -1; return 1; } /** Copy NULL terminated string. * * Copy at most 'len' characters from string 'src' to 'dest'. * If 'src' is shorter than 'len', '\0' is inserted behind the * last copied character. * * @param src Source string. * @param dest Destination buffer. * @param len Size of destination buffer. * */ void strncpy(char *dest, const char *src, size_t len) { unsigned int i; for (i = 0; i < len; i++) { if (!(dest[i] = src[i])) return; } dest[i - 1] = '\0'; } /** Find first occurence of character in string. * * @param s String to search. * @param i Character to look for. * * @return Pointer to character in @a s or NULL if not found. */ extern char *strchr(const char *s, int i) { while (*s != '\0') { if (*s == i) return (char *) s; ++s; } return NULL; } /** @} */