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Diffstat (limited to '')
-rw-r--r-- | src/string/strlen.c | 53 | ||||
-rw-r--r-- | src/wchar/wcslen.c | 52 |
2 files changed, 105 insertions, 0 deletions
diff --git a/src/string/strlen.c b/src/string/strlen.c new file mode 100644 index 0000000..7023cc0 --- /dev/null +++ b/src/string/strlen.c @@ -0,0 +1,53 @@ +/** + * 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 <http://www.gnu.org/licenses/>. + */ +#include <string.h> +#include <stddef.h> + + + +/** + * Returns the number of bytes in a NUL-terminated + * string. This excludes the NUL byte. + * + * @param str The string. + * @return The number of bytes before the first NUL byte. + */ +size_t strlen(const char* str) +{ + /* TODO optimise strlen */ + char* s = str; + while (*str++); + return (size_t)(s - 1 - str); +} + + +/** + * Variant of `strlen` that only inspects the + * beginning of s string. + * + * @param str The string. + * @param maxlen The number of bytes to inspect, at most. + * @return The number of bytes before, the first NUL byte. + * `maxlen` if no NUL byte was found. + */ +size_t strnlen(const char* str, size_t maxlen) +{ + const char* end = memchr(str, 0, maxlen); + return end == NULL ? maxlen : (size_t)(end - str); +} + diff --git a/src/wchar/wcslen.c b/src/wchar/wcslen.c new file mode 100644 index 0000000..ad81227 --- /dev/null +++ b/src/wchar/wcslen.c @@ -0,0 +1,52 @@ +/** + * 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 <http://www.gnu.org/licenses/>. + */ +#include <wchar.h> +#include <stddef.h> + + + +/** + * `wchar_t` version of `strlen`. + * + * @param str The string. + * @return The number of `wchar_t`:s before the + * first NUL character. + */ +size_t wcslen(const wchar_t* str) +{ + const wchar_t* s = str; + while (*s++); + return (size_t)(s - 1 - str); +} + + +/** + * `wchar_t` version of `strnlen`. + * + * @param str The string. + * @param maxlen The number of bytes to inspect, at most. + * @return The number of `wchar_t`:s before the + * first NUL character. `maxlen` if no + * NUL character was found. + */ +size_t wcsnlen(const wchar_t* str, size_t maxlen) +{ + const wchar_t* end = wmemchr(str, 0, maxlen); + return end == NULL ? maxlen : (size_t)(end - str); +} + |