add memcasecmp and wmemcasecmp

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

1 files changed, 29 insertions, 0 deletions

diff --git a/src/string/strcmp.c b/src/string/strcmp.c
index 066b7c1..bffb2ad 100644
--- a/src/string/strcmp.c
+++ b/src/string/strcmp.c
@@ -45,6 +45,35 @@ int memcmp(const void* a, const void* b, size_t size)
 
 
 /**
+ * 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;
+}
+
+
+/**
  * Compare two strings alphabetically in a case sensitive manner.
  * 
  * @param   a  A negative value is returned if this is the lesser.