fs/io: move to io/

src/lib/zlib/GzipOutputStream.cxx

@@ -0,0 +1,101 @@
+/*
+ * Copyright (C) 2014-2018 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 "GzipOutputStream.hxx"
+#include "lib/zlib/Error.hxx"
+
+GzipOutputStream::GzipOutputStream(OutputStream &_next)
+	:next(_next)
+{
+	z.next_in = nullptr;
+	z.avail_in = 0;
+	z.zalloc = Z_NULL;
+	z.zfree = Z_NULL;
+	z.opaque = Z_NULL;
+
+	constexpr int windowBits = 15;
+	constexpr int gzip_encoding = 16;
+
+	int result = deflateInit2(&z, Z_DEFAULT_COMPRESSION, Z_DEFLATED,
+				  windowBits | gzip_encoding,
+				  8, Z_DEFAULT_STRATEGY);
+	if (result != Z_OK)
+		throw ZlibError(result);
+}
+
+GzipOutputStream::~GzipOutputStream()
+{
+	deflateEnd(&z);
+}
+
+void
+GzipOutputStream::Flush()
+{
+	/* no more input */
+	z.next_in = nullptr;
+	z.avail_in = 0;
+
+	while (true) {
+		Bytef output[16384];
+		z.next_out = output;
+		z.avail_out = sizeof(output);
+
+		int result = deflate(&z, Z_FINISH);
+		if (z.next_out > output)
+			next.Write(output, z.next_out - output);
+
+		if (result == Z_STREAM_END)
+			break;
+		else if (result != Z_OK)
+			throw ZlibError(result);
+	}
+}
+
+void
+GzipOutputStream::Write(const void *_data, size_t size)
+{
+	/* zlib's API requires non-const input pointer */
+	void *data = const_cast<void *>(_data);
+
+	z.next_in = reinterpret_cast<Bytef *>(data);
+	z.avail_in = size;
+
+	while (z.avail_in > 0) {
+		Bytef output[16384];
+		z.next_out = output;
+		z.avail_out = sizeof(output);
+
+		int result = deflate(&z, Z_NO_FLUSH);
+		if (result != Z_OK)
+			throw ZlibError(result);
+
+		if (z.next_out > output)
+			next.Write(output, z.next_out - output);
+	}
+}