1 files changed, 60 insertions, 0 deletions
diff --git a/src/pdclib/functions/string/strncat.c b/src/pdclib/functions/string/strncat.c
new file mode 100644
index 0000000..ba20edc
--- /dev/null
+++ b/src/pdclib/functions/string/strncat.c
@@ -0,0 +1,60 @@
+/* strncat( 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 <string.h>
+
+#ifndef REGTEST
+
+char * strncat( char * _PDCLIB_restrict s1, const char * _PDCLIB_restrict s2, size_t n )
+{
+    char * rc = s1;
+    while ( *s1 )
+    {
+        ++s1;
+    }
+    while ( n && ( *s1++ = *s2++ ) )
+    {
+        --n;
+    }
+    if ( n == 0 )
+    {
+        *s1 = '\0';
+    }
+    return rc;
+}
+
+#endif
+
+#ifdef TEST
+
+#include "_PDCLIB_test.h"
+
+int main( void )
+{
+    char s[] = "xx\0xxxxxx";
+    TESTCASE( strncat( s, abcde, 10 ) == s );
+    TESTCASE( s[2] == 'a' );
+    TESTCASE( s[6] == 'e' );
+    TESTCASE( s[7] == '\0' );
+    TESTCASE( s[8] == 'x' );
+    s[0] = '\0';
+    TESTCASE( strncat( s, abcdx, 10 ) == s );
+    TESTCASE( s[4] == 'x' );
+    TESTCASE( s[5] == '\0' );
+    TESTCASE( strncat( s, "\0", 10 ) == s );
+    TESTCASE( s[5] == '\0' );
+    TESTCASE( s[6] == 'e' );
+    TESTCASE( strncat( s, abcde, 0 ) == s );
+    TESTCASE( s[5] == '\0' );
+    TESTCASE( s[6] == 'e' );
+    TESTCASE( strncat( s, abcde, 3 ) == s );
+    TESTCASE( s[5] == 'a' );
+    TESTCASE( s[7] == 'c' );
+    TESTCASE( s[8] == '\0' );
+    return TEST_RESULTS;
+}
+
+#endif