/* * Copyright (c) 2007 Mans Rullgard * * This file is part of FFmpeg. * * FFmpeg is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * FFmpeg is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with FFmpeg; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ #ifndef AVUTIL_AVSTRING_H #define AVUTIL_AVSTRING_H #include <stddef.h> #include <stdint.h> #include "attributes.h" /** * @addtogroup lavu_string * @{ */ /** * Return non-zero if pfx is a prefix of str. If it is, *ptr is set to * the address of the first character in str after the prefix. * * @param str input string * @param pfx prefix to test * @param ptr updated if the prefix is matched inside str * @return non-zero if the prefix matches, zero otherwise */ int av_strstart(const char *str, const char *pfx, const char **ptr); /** * Return non-zero if pfx is a prefix of str independent of case. If * it is, *ptr is set to the address of the first character in str * after the prefix. * * @param str input string * @param pfx prefix to test * @param ptr updated if the prefix is matched inside str * @return non-zero if the prefix matches, zero otherwise */ int av_stristart(const char *str, const char *pfx, const char **ptr); /** * Locate the first case-independent occurrence in the string haystack * of the string needle. A zero-length string needle is considered to * match at the start of haystack. * * This function is a case-insensitive version of the standard strstr(). * * @param haystack string to search in * @param needle string to search for * @return pointer to the located match within haystack * or a null pointer if no match */ char *av_stristr(const char *haystack, const char *needle); /** * Locate the first occurrence of the string needle in the string haystack * where not more than hay_length characters are searched. A zero-length * string needle is considered to match at the start of haystack. * * This function is a length-limited version of the standard strstr(). * * @param haystack string to search in * @param needle string to search for * @param hay_length length of string to search in * @return pointer to the located match within haystack * or a null pointer if no match */ char *av_strnstr(const char *haystack, const char *needle, size_t hay_length); /** * Copy the string src to dst, but no more than size - 1 bytes, and * null-terminate dst. * * This function is the same as BSD strlcpy(). * * @param dst destination buffer * @param src source string * @param size size of destination buffer * @return the length of src * * @warning since the return value is the length of src, src absolutely * _must_ be a properly 0-terminated string, otherwise this will read beyond * the end of the buffer and possibly crash. */ size_t av_strlcpy(char *dst, const char *src, size_t size); /** * Append the string src to the string dst, but to a total length of * no more than size - 1 bytes, and null-terminate dst. * * This function is similar to BSD strlcat(), but differs when * size <= strlen(dst). * * @param dst destination buffer * @param src source string * @param size size of destination buffer * @return the total length of src and dst * * @warning since the return value use the length of src and dst, these * absolutely _must_ be a properly 0-terminated strings, otherwise this * will read beyond the end of the buffer and possibly crash. */ size_t av_strlcat(char *dst, const char *src, size_t size); /** * Append output to a string, according to a format. Never write out of * the destination buffer, and always put a terminating 0 within * the buffer. * @param dst destination buffer (string to which the output is * appended) * @param size total size of the destination buffer * @param fmt printf-compatible format string, specifying how the * following parameters are used * @return the length of the string that would have been generated * if enough space had been available */ size_t av_strlcatf(char *dst, size_t size, const char *fmt, ...) av_printf_format(3, 4); /** * Get the count of continuous non zero chars starting from the beginning. * * @param len maximum number of characters to check in the string, that * is the maximum value which is returned by the function */ static inline size_t av_strnlen(const char *s, size_t len) { size_t i; for (i = 0; i < len && s[i]; i++) ; return i; } /** * Print arguments following specified format into a large enough auto * allocated buffer. It is similar to GNU asprintf(). * @param fmt printf-compatible format string, specifying how the * following parameters are used. * @return the allocated string * @note You have to free the string yourself with av_free(). */ char *av_asprintf(const char *fmt, ...) av_printf_format(1, 2); /** * Convert a number to an av_malloced string. */ char *av_d2str(double d); /** * Unescape the given string until a non escaped terminating char, * and return the token corresponding to the unescaped string. * * The normal \ and ' escaping is supported. Leading and trailing * whitespaces are removed, unless they are escaped with '\' or are * enclosed between ''. * * @param buf the buffer to parse, buf will be updated to point to the * terminating char * @param term a 0-terminated list of terminating chars * @return the malloced unescaped string, which must be av_freed by * the user, NULL in case of allocation failure */ char *av_get_token(const char **buf, const char *term); /** * Split the string into several tokens which can be accessed by * successive calls to av_strtok(). * * A token is defined as a sequence of characters not belonging to the * set specified in delim. * * On the first call to av_strtok(), s should point to the string to * parse, and the value of saveptr is ignored. In subsequent calls, s * should be NULL, and saveptr should be unchanged since the previous * call. * * This function is similar to strtok_r() defined in POSIX.1. * * @param s the string to parse, may be NULL * @param delim 0-terminated list of token delimiters, must be non-NULL * @param saveptr user-provided pointer which points to stored * information necessary for av_strtok() to continue scanning the same * string. saveptr is updated to point to the next character after the * first delimiter found, or to NULL if the string was terminated * @return the found token, or NULL when no token is found */ char *av_strtok(char *s, const char *delim, char **saveptr); /** * Locale-independent conversion of ASCII isdigit. */ static inline av_const int av_isdigit(int c) { return c >= '0' && c <= '9'; } /** * Locale-independent conversion of ASCII isgraph. */ static inline av_const int av_isgraph(int c) { return c > 32 && c < 127; } /** * Locale-independent conversion of ASCII isspace. */ static inline av_const int av_isspace(int c) { return c == ' ' || c == '\f' || c == '\n' || c == '\r' || c == '\t' || c == '\v'; } /** * Locale-independent conversion of ASCII characters to uppercase. */ static inline av_const int av_toupper(int c) { if (c >= 'a' && c <= 'z') c ^= 0x20; return c; } /** * Locale-independent conversion of ASCII characters to lowercase. */ static inline av_const int av_tolower(int c) { if (c >= 'A' && c <= 'Z') c ^= 0x20; return c; } /** * Locale-independent conversion of ASCII isxdigit. */ static inline av_const int av_isxdigit(int c) { c = av_tolower(c); return av_isdigit(c) || (c >= 'a' && c <= 'f'); } /** * Locale-independent case-insensitive compare. * @note This means only ASCII-range characters are case-insensitive */ int av_strcasecmp(const char *a, const char *b); /** * Locale-independent case-insensitive compare. * @note This means only ASCII-range characters are case-insensitive */ int av_strncasecmp(const char *a, const char *b, size_t n); /** * Locale-independent strings replace. * @note This means only ASCII-range characters are replace */ char *av_strireplace(const char *str, const char *from, const char *to); /** * Thread safe basename. * @param path the string to parse, on DOS both \ and / are considered separators. * @return pointer to the basename substring. * If path does not contain a slash, the function returns a copy of path. * If path is a NULL pointer or points to an empty string, a pointer * to a string "." is returned. */ const char *av_basename(const char *path); /** * Thread safe dirname. * @param path the string to parse, on DOS both \ and / are considered separators. * @return A pointer to a string that's the parent directory of path. * If path is a NULL pointer or points to an empty string, a pointer * to a string "." is returned. * @note the function may modify the contents of the path, so copies should be passed. */ const char *av_dirname(char *path); /** * Match instances of a name in a comma-separated list of names. * List entries are checked from the start to the end of the names list, * the first match ends further processing. If an entry prefixed with '-' * matches, then 0 is returned. The "ALL" list entry is considered to * match all names. * * @param name Name to look for. * @param names List of names. * @return 1 on match, 0 otherwise. */ int av_match_name(const char *name, const char *names); /** * Append path component to the existing path. * Path separator '/' is placed between when needed. * Resulting string have to be freed with av_free(). * @param path base path * @param component component to be appended * @return new path or NULL on error. */ char *av_append_path_component(const char *path, const char *component); enum AVEscapeMode { AV_ESCAPE_MODE_AUTO, ///< Use auto-selected escaping mode. AV_ESCAPE_MODE_BACKSLASH, ///< Use backslash escaping. AV_ESCAPE_MODE_QUOTE, ///< Use single-quote escaping. }; /** * Consider spaces special and escape them even in the middle of the * string. * * This is equivalent to adding the whitespace characters to the special * characters lists, except it is guaranteed to use the exact same list * of whitespace characters as the rest of libavutil. */ #define AV_ESCAPE_FLAG_WHITESPACE (1 << 0) /** * Escape only specified special characters. * Without this flag, escape also any characters that may be considered * special by av_get_token(), such as the single quote. */ #define AV_ESCAPE_FLAG_STRICT (1 << 1) /** * Escape string in src, and put the escaped string in an allocated * string in *dst, which must be freed with av_free(). * * @param dst pointer where an allocated string is put * @param src string to escape, must be non-NULL * @param special_chars string containing the special characters which * need to be escaped, can be NULL * @param mode escape mode to employ, see AV_ESCAPE_MODE_* macros. * Any unknown value for mode will be considered equivalent to * AV_ESCAPE_MODE_BACKSLASH, but this behaviour can change without * notice. * @param flags flags which control how to escape, see AV_ESCAPE_FLAG_ macros * @return the length of the allocated string, or a negative error code in case of error * @see av_bprint_escape() */ av_warn_unused_result int av_escape(char **dst, const char *src, const char *special_chars, enum AVEscapeMode mode, int flags); #define AV_UTF8_FLAG_ACCEPT_INVALID_BIG_CODES 1 ///< accept codepoints over 0x10FFFF #define AV_UTF8_FLAG_ACCEPT_NON_CHARACTERS 2 ///< accept non-characters - 0xFFFE and 0xFFFF #define AV_UTF8_FLAG_ACCEPT_SURROGATES 4 ///< accept UTF-16 surrogates codes #define AV_UTF8_FLAG_EXCLUDE_XML_INVALID_CONTROL_CODES 8 ///< exclude control codes not accepted by XML #define AV_UTF8_FLAG_ACCEPT_ALL \ AV_UTF8_FLAG_ACCEPT_INVALID_BIG_CODES|AV_UTF8_FLAG_ACCEPT_NON_CHARACTERS|AV_UTF8_FLAG_ACCEPT_SURROGATES /** * Read and decode a single UTF-8 code point (character) from the * buffer in *buf, and update *buf to point to the next byte to * decode. * * In case of an invalid byte sequence, the pointer will be updated to * the next byte after the invalid sequence and the function will * return an error code. * * Depending on the specified flags, the function will also fail in * case the decoded code point does not belong to a valid range. * * @note For speed-relevant code a carefully implemented use of * GET_UTF8() may be preferred. * * @param codep pointer used to return the parsed code in case of success. * The value in *codep is set even in case the range check fails. * @param bufp pointer to the address the first byte of the sequence * to decode, updated by the function to point to the * byte next after the decoded sequence * @param buf_end pointer to the end of the buffer, points to the next * byte past the last in the buffer. This is used to * avoid buffer overreads (in case of an unfinished * UTF-8 sequence towards the end of the buffer). * @param flags a collection of AV_UTF8_FLAG_* flags * @return >= 0 in case a sequence was successfully read, a negative * value in case of invalid sequence */ av_warn_unused_result int av_utf8_decode(int32_t *codep, const uint8_t **bufp, const uint8_t *buf_end, unsigned int flags); /** * Check if a name is in a list. * @returns 0 if not found, or the 1 based index where it has been found in the * list. */ int av_match_list(const char *name, const char *list, char separator); /** * See libc sscanf manual for more information. * Locale-independent sscanf implementation. */ int av_sscanf(const char *string, const char *format, ...); /** * @} */ #endif /* AVUTIL_AVSTRING_H */