path: root/src/string/str/strstr.c

/**
 * 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.
 * 
 * @param   haystack  The string to search.
 * @param   needle    The sought after substring.
 * @return            Pointer to the first occurrence of the
 *                    substring, `NULL` if not found.
 */
char* (strstr)(const char* haystack, const char* needle)
{
  if (*needle && !(needle[1]))
    return (strchr)(haystack, *needle);
  return (memmem)(haystack, strlen(haystack), needle, strlen(needle));
}