Added search functions.

[pdclib] / functions / string / strstr.c

diff --git a/functions/string/strstr.c b/functions/string/strstr.c
new file mode 100644 (file)
index 0000000..fc5950d
--- /dev/null
+++ b/functions/string/strstr.c
@@ -0,0 +1,33 @@
+/* $Id$ */
+
+/* Release $Name$ */
+
+/* strstr( const 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>
+
+char * strstr( const char * s1, const char * s2 )
+{
+    const char * p1 = s1;
+    const char * p2;
+    while ( *s1 )
+    {
+        p2 = s2;
+        while ( *p2 && ( *p1 == *p2 ) )
+        {
+            ++p1;
+            ++p2;
+        }
+        if ( ! *p2 )
+        {
+            return (char *) s1;
+        }
+        ++s1;
+        p1 = s1;
+    }
+    return NULL;
+}