split out string/strn/ from string/str/

Signed-off-by: Mattias Andrée <maandree@operamail.com>

1 files changed, 39 insertions, 0 deletions

diff --git a/src/string/strn/strnstr.c b/src/string/strn/strnstr.c
new file mode 100644
index 0000000..8db61ac
--- /dev/null
+++ b/src/string/strn/strnstr.c
@@ -0,0 +1,39 @@
+/**
+ * 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>
+
+
+
+/**
+ * Finds the first occurrence of a substring.
+ * This search is case sensitive.
+ * 
+ * This is a slibc extension added for because it was useful
+ * in implementing slibc itself.
+ * 
+ * @param   haystack  The string to search.
+ * @param   needle    The sought after substring.
+ * @param   maxlen    The maximum number of character to search.
+ * @return            Pointer to the first occurrence of the
+ *                    substring, `NULL` if not found.
+ */
+char* (strnstr)(const char* haystack, const char* needle, size_t maxlen)
+{
+  return (memmem)(haystack, strnlen(haystack, maxlen), needle, strlen(needle));
+}
+