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-rw-r--r--src/string/strrchr.c48
1 files changed, 48 insertions, 0 deletions
diff --git a/src/string/strrchr.c b/src/string/strrchr.c
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+++ b/src/string/strrchr.c
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+/**
+ * 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>
+
+
+# pragma GCC diagnostic ignored "-Wdiscarded-qualifiers"
+
+
+
+/**
+ * Find the last occurrence of a byte in a string.
+ *
+ * For improved performace, use `memrchr` instead of
+ * this function if you already know the length of the
+ * string.
+ *
+ * @param string The string to search.
+ * The terminating NUL character is
+ * considered a part of the string.
+ * @param c The sought after character.
+ * @return Pointer to the last occurrence of `c`,
+ * `NULL` if none were found.
+ */
+char* (strrchr)(const char* string, int c)
+{
+ char* r = NULL;
+ for (;;)
+ if (*string == c)
+ r = string;
+ else if (!*string++)
+ return c ? r : (string - 1);
+}
+