Extract strlcpy and strlcmp to libtor-string

src/lib/string/compat_string.h

@@ -0,0 +1,39 @@
+/* Copyright (c) 2003-2004, Roger Dingledine
+ * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
+ * Copyright (c) 2007-2018, The Tor Project, Inc. */
+/* See LICENSE for licensing information */
+
+#ifndef TOR_COMPAT_STRING_H
+#define TOR_COMPAT_STRING_H
+
+#include "orconfig.h"
+#include "lib/cc/compat_compiler.h"
+
+#include <stddef.h>
+
+/* ===== String compatibility */
+#ifdef _WIN32
+/* Windows names string functions differently from most other platforms. */
+#define strncasecmp _strnicmp
+#define strcasecmp _stricmp
+#endif
+
+#if defined __APPLE__
+/* On OSX 10.9 and later, the overlap-checking code for strlcat would
+ * appear to have a severe bug that can sometimes cause aborts in Tor.
+ * Instead, use the non-checking variants.  This is sad.
+ *
+ * See https://trac.torproject.org/projects/tor/ticket/15205
+ */
+#undef strlcat
+#undef strlcpy
+#endif /* defined __APPLE__ */
+
+#ifndef HAVE_STRLCAT
+size_t strlcat(char *dst, const char *src, size_t siz) ATTR_NONNULL((1,2));
+#endif
+#ifndef HAVE_STRLCPY
+size_t strlcpy(char *dst, const char *src, size_t siz) ATTR_NONNULL((1,2));
+#endif
+
+#endif