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-rw-r--r--src/string/memcasecmp.c50
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diff --git a/src/string/memcasecmp.c b/src/string/memcasecmp.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>
+#include <ctype.h>
+
+
+
+/**
+ * Compare two memory segments alphabetically in a case insensitive manner.
+ *
+ * This is a slibc extension added because it was useful
+ * in implementing slibc itself.
+ *
+ * @param a A negative value is returned if this is the lesser.
+ * @param b A positive value is returned if this is the lesser.
+ * @param size The size of the segments.
+ * @return Zero is returned if `a` and `b` are equal, otherwise,
+ * see the specifications for `a` and `b`.
+ */
+int memcasecmp(const void* a, const void* b, size_t size)
+{
+ const signed char* s1 = a;
+ const signed char* s2 = b;
+ int c1, c2;
+ for (; size--; s1++, s2++)
+ if (*s1 != *s2)
+ {
+ c1 = isalpha(*s1) ? tolower(*s1) : (int)*s1;
+ c2 = isalpha(*s2) ? tolower(*s2) : (int)*s2;
+ if ((c1 -= c2))
+ return c1;
+ }
+ return 0;
+}
+