From 729db5025b7f98adf17c87a79492b577c59f9704 Mon Sep 17 00:00:00 2001 From: Mattias Andrée Date: Tue, 1 Sep 2015 15:39:09 +0200 Subject: add strtok functions MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Signed-off-by: Mattias Andrée --- src/string/strtok.c | 112 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 112 insertions(+) create mode 100644 src/string/strtok.c (limited to 'src/string/strtok.c') diff --git a/src/string/strtok.c b/src/string/strtok.c new file mode 100644 index 0000000..04668fc --- /dev/null +++ b/src/string/strtok.c @@ -0,0 +1,112 @@ +/** + * slibc — Yet another C library + * Copyright © 2015 Mattias Andrée (maandree@member.fsf.org) + * + * This program is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, either version 3 of the License, or + * (at your option) any later version. + * + * This program 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 General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see . + */ +#include +#include + + + +/** + * Tokenise a string. + * + * @param string The string to tokenise on the first, + * `NULL` on subsequent calls. + * All bytes found in `delimiters` will + * be overriden with NUL bytes. + * @param delimiters Delimiting bytes (not characters). + * @return The next non-empty string that does not + * contain a byte from `delimiters`. The + * returned string will be as long as possible. + * `NULL` is returned the search as reached + * the end of the string, and there therefore + * are no more tokens. + */ +char* strtok(char* restrict string, const char* restrict delimiters) +{ + static char* state = NULL; + if (string == NULL) + state = NULL; + return strtok_r(string, delimiters, &state); +} + + +/** + * Tokenise a string. + * + * @param string The string to tokenise on the first, + * `NULL` on subsequent calls. + * All bytes found in `delimiters` will + * be overriden with NUL bytes. + * @param delimiters Delimiting bytes (not characters). + * @param state Pointer to a `char*` that the function + * can use to keep track of its state. + * It is reasonable to make it point to `NULL` + * on the first call. + * @return The next non-empty string that does not + * contain a byte from `delimiters`. The + * returned string will be as long as possible. + * `NULL` is returned the search as reached + * the end of the string, and there therefore + * are no more tokens. + */ +char* strtok_r(char* restrict string, const char* restrict delimiters, + char** restrict state) +{ + char* r; + if (string == NULL) + *state = string; + for (;;) + { + r = strsep(state, delimiters); + if (r == NULL) + return NULL; + if (*r) + return r; + } +} + + +/** + * Tokenise a string. + * + * @param string Pointer to the string to tokenise on the first call, + * will be updated to keep track of the state. + * All bytes found in `delimiters` will + * be overriden with NUL bytes. + * @param delimiters Delimiting bytes (not characters). + * @return The next, possibly empty, string that does + * not contain a byte from `delimiters`. The + * returned string will be as long as possible. + * `NULL` is returned the search as reached + * the end of the string, and there therefore + * are no more tokens. + */ +char* strsep(char** restrict string, const char* restrict delimiters) +{ + char* r = *string; + char* next; + if (r == NULL) + return NULL; + + next = stpbrk(string, delimiters); + if (next != NULL) + *next++ = 0; + *string = next; + + return r; +} + -- cgit v1.2.3-70-g09d2