util/StringUtil: add wchar_t overloads

Makefile.am

@@ -378,6 +378,7 @@ libutil_a_SOURCES = \
 	src/util/CharUtil.hxx \
 	src/util/NumberParser.hxx \
 	src/util/StringUtil.cxx src/util/StringUtil.hxx \
+	src/util/WStringUtil.cxx src/util/WStringUtil.hxx \
 	src/util/StringAPI.hxx \
 	src/util/WStringAPI.hxx \
 	src/util/DivideString.cxx src/util/DivideString.hxx \

src/util/StringUtil.hxx

@@ -24,6 +24,10 @@
 
 #include <stddef.h>
 
+#ifdef _UNICODE
+#include "WStringUtil.hxx"
+#endif
+
 gcc_pure
 bool
 StringStartsWith(const char *haystack, const char *needle);

src/util/WStringUtil.cxx

@@ -0,0 +1,58 @@
+/*
+ * Copyright (C) 2003-2015 The Music Player Daemon Project
+ * http://www.musicpd.org
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include "WStringUtil.hxx"
+#include "WStringAPI.hxx"
+#include "ASCII.hxx"
+
+#include <algorithm>
+
+#include <assert.h>
+#include <string.h>
+
+bool
+StringStartsWith(const wchar_t *haystack, const wchar_t *needle)
+{
+  return memcmp(haystack, needle, StringLength(needle) * sizeof(needle[0])) == 0;
+}
+
+bool
+StringEndsWith(const wchar_t *haystack, const wchar_t *needle)
+{
+  const size_t haystack_length = StringLength(haystack);
+  const size_t needle_length = StringLength(needle);
+
+  return haystack_length >= needle_length &&
+    StringIsEqual(haystack + haystack_length - needle_length, needle);
+}
+
+const wchar_t *
+FindStringSuffix(const wchar_t *p, const wchar_t *suffix)
+{
+	const size_t p_length = StringLength(p);
+	const size_t suffix_length = StringLength(suffix);
+
+	if (p_length < suffix_length)
+		return nullptr;
+
+	const auto *q = p + p_length - suffix_length;
+	return memcmp(q, suffix, suffix_length * sizeof(*suffix)) == 0
+		? q
+		: nullptr;
+}

src/util/WStringUtil.hxx

@@ -0,0 +1,43 @@
+/*
+ * Copyright (C) 2003-2015 The Music Player Daemon Project
+ * http://www.musicpd.org
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#ifndef WSTRING_UTIL_HXX
+#define WSTRING_UTIL_HXX
+
+#include "Compiler.h"
+
+#include <wchar.h>
+
+gcc_pure
+bool
+StringStartsWith(const wchar_t *haystack, const wchar_t *needle);
+
+gcc_pure
+bool
+StringEndsWith(const wchar_t *haystack, const wchar_t *needle);
+
+/**
+ * Check if the given string ends with the specified suffix.  If yes,
+ * returns the position of the suffix, and nullptr otherwise.
+ */
+gcc_pure
+const wchar_t *
+FindStringSuffix(const wchar_t *p, const wchar_t *suffix);
+
+#endif