X-Git-Url: https://pd.if.org/git/?p=pdclib;a=blobdiff_plain;f=functions%2Fstring%2Fstrcat.c;h=50d66ee0891c681438d95f6fc8200235ef459968;hp=cb0c0a128d83d93cdbd8e3d43229236dc6904fa4;hb=da0f3f353d417fed71f358a48d5d5394145e460d;hpb=34893ecc2200dc7017c36a54cb6c5f4c2378b5ec

diff --git a/functions/string/strcat.c b/functions/string/strcat.c
index cb0c0a1..50d66ee 100644
--- a/functions/string/strcat.c
+++ b/functions/string/strcat.c
@@ -1,8 +1,44 @@
-// ----------------------------------------------------------------------------
-// $Id$
-// ----------------------------------------------------------------------------
-// Public Domain C Library - http://pdclib.sourceforge.net
-// This code is Public Domain. Use, modify, and redistribute at will.
-// ----------------------------------------------------------------------------
-
-char * strcat( char * restrict s1, const char * restrict s2 ) { /* TODO */ };
+/* strcat( char *, const char * )
+
+   This file is part of the Public Domain C Library (PDCLib).
+   Permission is granted to use, modify, and / or redistribute at will.
+*/
+
+#include <string.h>
+
+#ifndef REGTEST
+
+char * strcat( char * _PDCLIB_restrict s1, const char * _PDCLIB_restrict s2 )
+{
+    char * rc = s1;
+    if ( *s1 )
+    {
+        while ( *++s1 );
+    }
+    while ( (*s1++ = *s2++) );
+    return rc;
+}
+
+#endif
+
+#ifdef TEST
+#include "_PDCLIB_test.h"
+
+int main( void )
+{
+    char s[] = "xx\0xxxxxx";
+    TESTCASE( strcat( s, abcde ) == s );
+    TESTCASE( s[2] == 'a' );
+    TESTCASE( s[6] == 'e' );
+    TESTCASE( s[7] == '\0' );
+    TESTCASE( s[8] == 'x' );
+    s[0] = '\0';
+    TESTCASE( strcat( s, abcdx ) == s );
+    TESTCASE( s[4] == 'x' );
+    TESTCASE( s[5] == '\0' );
+    TESTCASE( strcat( s, "\0" ) == s );
+    TESTCASE( s[5] == '\0' );
+    TESTCASE( s[6] == 'e' );
+    return TEST_RESULTS;
+}
+#endif