X-Git-Url: https://pd.if.org/git/?p=pdclib;a=blobdiff_plain;f=functions%2Fstring%2Fstrncmp.c;h=e1ec0de66e9797c9739555b4b901116ea4813920;hp=9e5e615f4c42e7a4c90fb3625c297f01c329c90e;hb=da0f3f353d417fed71f358a48d5d5394145e460d;hpb=1d9d92ba957a0b8307c9a65c35867fde68e6533b

diff --git a/functions/string/strncmp.c b/functions/string/strncmp.c
index 9e5e615..e1ec0de 100644
--- a/functions/string/strncmp.c
+++ b/functions/string/strncmp.c
@@ -1,22 +1,52 @@
-/* ----------------------------------------------------------------------------
- * $Id$
- * ----------------------------------------------------------------------------
- * Public Domain C Library - http://pdclib.sourceforge.net
- * This code is Public Domain. Use, modify, and redistribute at will.
- * --------------------------------------------------------------------------*/
+/* strncmp( const char *, const char *, size_t )
 
-#include <__size_t.h>
+   This file is part of the Public Domain C Library (PDCLib).
+   Permission is granted to use, modify, and / or redistribute at will.
+*/
 
-int strncmp( const char * src_1, const char * src_2, size_t n )
+#include <string.h>
+
+#ifndef REGTEST
+
+int strncmp( const char * s1, const char * s2, size_t n )
 {
-    while ( ( n-- != 0 ) && ( *src_1 == *src_2 ) )
+    while ( *s1 && n && ( *s1 == *s2 ) )
     {
-        ++src_1;
-        ++src_2;
+        ++s1;
+        ++s2;
+        --n;
     }
-    if ( ( n == 0 ) )
+    if ( n == 0 )
     {
         return 0;
     }
-    return ( *src_1 - *src_2 );
+    else
+    {
+        return ( *(unsigned char *)s1 - *(unsigned char *)s2 );
+    }
+}
+
+#endif
+
+#ifdef TEST
+#include "_PDCLIB_test.h"
+
+int main( void )
+{
+    char cmpabcde[] = "abcde\0f";
+    char cmpabcd_[] = "abcde\xfc";
+    char empty[] = "";
+    char x[] = "x";
+    TESTCASE( strncmp( abcde, cmpabcde, 5 ) == 0 );
+    TESTCASE( strncmp( abcde, cmpabcde, 10 ) == 0 );
+    TESTCASE( strncmp( abcde, abcdx, 5 ) < 0 );
+    TESTCASE( strncmp( abcdx, abcde, 5 ) > 0 );
+    TESTCASE( strncmp( empty, abcde, 5 ) < 0 );
+    TESTCASE( strncmp( abcde, empty, 5 ) > 0 );
+    TESTCASE( strncmp( abcde, abcdx, 4 ) == 0 );
+    TESTCASE( strncmp( abcde, x, 0 ) == 0 );
+    TESTCASE( strncmp( abcde, x, 1 ) < 0 );
+    TESTCASE( strncmp( abcde, cmpabcd_, 10 ) < 0 );
+    return TEST_RESULTS;
 }
+#endif