lib/gcrypt/MD5: move code to util/HexFormat.cxx

Makefile.am

@@ -493,6 +493,7 @@ libutil_a_SOURCES = \
 	src/util/CharUtil.hxx \
 	src/util/WCharUtil.hxx \
 	src/util/NumberParser.hxx \
+	src/util/HexFormat.cxx src/util/HexFormat.hxx \
 	src/util/MimeType.cxx src/util/MimeType.hxx \
 	src/util/StringBuffer.hxx \
 	src/util/StringFormat.hxx \

src/lib/gcrypt/MD5.cxx

@@ -29,6 +29,7 @@
 
 #include "MD5.hxx"
 #include "Hash.hxx"
+#include "util/HexFormat.hxx"
 
 #include <stdio.h>
 
@@ -42,13 +43,5 @@ StringBuffer<33>
 MD5Hex(ConstBuffer<void> input) noexcept
 {
 	const auto raw = MD5(input);
-	StringBuffer<33> result;
-
-	char *p = result.data();
-	for (const auto i : raw) {
-		sprintf(p, "%02x", i);
-		p += 2;
-	}
-
-	return result;
+	return HexFormatBuffer<raw.size()>(&raw.front());
 }

src/util/HexFormat.cxx

@@ -0,0 +1,43 @@
+/*
+ * Copyright (C) 2018 Max Kellermann <max.kellermann@gmail.com>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * - Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * - Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the
+ * distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
+ * FOUNDATION OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "HexFormat.hxx"
+
+#include <stdio.h>
+
+char *
+HexFormat(char *dest, ConstBuffer<uint8_t> src) noexcept
+{
+	for (auto i : src) {
+		sprintf(dest, "%02x", i);
+		dest += 2;
+	}
+
+	return dest;
+}

src/util/HexFormat.hxx

@@ -0,0 +1,64 @@
+/*
+ * Copyright (C) 2018 Max Kellermann <max.kellermann@gmail.com>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * - Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * - Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the
+ * distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
+ * FOUNDATION OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef HEX_FORMAT_HXX
+#define HEX_FORMAT_HXX
+
+#include "ConstBuffer.hxx"
+#include "StringBuffer.hxx"
+#include "Compiler.h"
+
+#include <stdint.h>
+
+/**
+ * Format the given byte sequence into a null-terminated hexadecimal
+ * string.
+ *
+ * @param dest the destination buffer; must be large enough to hold
+ * all hex digits plus the null terminator
+ * @return a pointer to the generated null terminator
+ */
+char *
+HexFormat(char *dest, ConstBuffer<uint8_t> src) noexcept;
+
+/**
+ * Like HexFormat(), but return a #StringBuffer with exactly the
+ * required size.
+ */
+template<size_t size>
+gcc_pure
+auto
+HexFormatBuffer(const uint8_t *src) noexcept
+{
+	StringBuffer<size * 2 + 1> dest;
+	HexFormat(dest.data(), {src, size});
+	return dest;
+}
+
+#endif