Reviewed.

[pdclib] / functions / string / memcmp.c

diff --git a/functions/string/memcmp.c b/functions/string/memcmp.c
index 43b7e585f348f3d112ef817009b94e38d97758ac..fdda92ce7689a8aa6aaaf7c125587d79c1a167b2 100644 (file)
--- a/functions/string/memcmp.c
+++ b/functions/string/memcmp.c
@@ -5,4 +5,20 @@
 // This code is Public Domain. Use, modify, and redistribute at will.
 // ----------------------------------------------------------------------------
 
-int memcmp( const void * s1, const void * s2, size_t n ) { /* TODO */ };
+#include <string.h>
+
+int memcmp( const void * src_1, const void * src_2, size_t n )
+{
+    const unsigned char * p1 = (const unsigned char *) src_1;
+    const unsigned char * p2 = (const unsigned char *) src_2;
+    while ( n-- )
+    {
+        if ( *p1 != *p2 )
+        {
+            return *p2 - *p1;
+        }
+        ++p1;
+        ++p2;
+    }
+    return 0;
+}