X-Git-Url: https://pd.if.org/git/?a=blobdiff_plain;f=functions%2Fstring%2Fstrncpy.c;h=da1397a93caaf2a7a1b6b3ebf5499f941f1f8236;hb=d865c4403fc91d1f1ac95ba76febcee9f429bb97;hp=31602ec8a9fef4709ce87b2904c821fb6256d2f4;hpb=1a0d9f7faca36f149db3b85c09a72528e0c73a83;p=pdclib

diff --git a/functions/string/strncpy.c b/functions/string/strncpy.c
index 31602ec..da1397a 100644
--- a/functions/string/strncpy.c
+++ b/functions/string/strncpy.c
@@ -1,40 +1,41 @@
-/* $Id$ */
-
-/* Release $Name$ */
-
 /* strncpy( char *, const char *, size_t )
 
    This file is part of the Public Domain C Library (PDCLib).
    Permission is granted to use, modify, and / or redistribute at will.
 */
 
-#include <_PDCLIB_aux.h>
 #include <string.h>
 
+#ifndef REGTEST
+
 char * strncpy( char * _PDCLIB_restrict s1, const char * _PDCLIB_restrict s2, size_t n )
 {
     char * rc = s1;
     while ( ( n > 0 ) && ( *s1++ = *s2++ ) )
     {
         /* Cannot do "n--" in the conditional as size_t is unsigned and we have
-        to check it again for >0 in the next loop.
+           to check it again for >0 in the next loop below, so we must not risk
+           underflow.
         */
         --n;
     }
-    while ( --n )
+    /* Checking against 1 as we missed the last --n in the loop above. */
+    while ( n-- > 1 )
     {
         *s1++ = '\0';
     }
     return rc;
 }
 
+#endif
+
 #ifdef TEST
-#include <_PDCLIB_test.h>
 
-int main()
+#include "_PDCLIB_test.h"
+
+int main( void )
 {
     char s[] = "xxxxxxx";
-    BEGIN_TESTS;
     TESTCASE( strncpy( s, "", 1 ) == s );
     TESTCASE( s[0] == '\0' );
     TESTCASE( s[1] == 'x' );
@@ -45,6 +46,11 @@ int main()
     TESTCASE( s[6] == 'x' );
     TESTCASE( strncpy( s, abcde, 7 ) == s );
     TESTCASE( s[6] == '\0' );
+    TESTCASE( strncpy( s, "xxxx", 3 ) == s );
+    TESTCASE( s[0] == 'x' );
+    TESTCASE( s[2] == 'x' );
+    TESTCASE( s[3] == 'd' );
     return TEST_RESULTS;
 }
+
 #endif