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-rw-r--r--src/io/stream/gzipstream.cpp456
1 files changed, 456 insertions, 0 deletions
diff --git a/src/io/stream/gzipstream.cpp b/src/io/stream/gzipstream.cpp
new file mode 100644
index 0000000..60d17f9
--- /dev/null
+++ b/src/io/stream/gzipstream.cpp
@@ -0,0 +1,456 @@
+// SPDX-License-Identifier: LGPL-2.1-or-later
+/** @file
+ * Zlib-enabled input and output streams
+ *//*
+ * Authors:
+ * see git history
+ * Bob Jamison <rjamison@titan.com>
+ *
+ *
+ * Copyright (C) 2018 Authors
+ * Released under GNU LGPL v2.1+, read the file 'COPYING' for more information.
+ */
+/*
+ * This is a thin wrapper of libz calls, in order
+ * to provide a simple interface to our developers
+ * for gzip input and output.
+ */
+
+#include "gzipstream.h"
+#include <cstdio>
+#include <cstdlib>
+#include <cstring>
+#include <string>
+
+namespace Inkscape
+{
+namespace IO
+{
+
+//#########################################################################
+//# G Z I P I N P U T S T R E A M
+//#########################################################################
+
+#define OUT_SIZE 4000
+
+/**
+ *
+ */
+GzipInputStream::GzipInputStream(InputStream &sourceStream)
+ : BasicInputStream(sourceStream),
+ loaded(false),
+ outputBuf(nullptr),
+ srcBuf(nullptr),
+ crc(0),
+ srcCrc(0),
+ srcSiz(0),
+ srcLen(0),
+ outputBufPos(0),
+ outputBufLen(0)
+{
+ memset( &d_stream, 0, sizeof(d_stream) );
+}
+
+/**
+ *
+ */
+GzipInputStream::~GzipInputStream()
+{
+ close();
+ if ( srcBuf ) {
+ delete[] srcBuf;
+ srcBuf = nullptr;
+ }
+ if ( outputBuf ) {
+ delete[] outputBuf;
+ outputBuf = nullptr;
+ }
+}
+
+/**
+ * Returns the number of bytes that can be read (or skipped over) from
+ * this input stream without blocking by the next caller of a method for
+ * this input stream.
+ */
+int GzipInputStream::available()
+{
+ if (closed || !outputBuf)
+ return 0;
+ return outputBufLen - outputBufPos;
+}
+
+
+/**
+ * Closes this input stream and releases any system resources
+ * associated with the stream.
+ */
+void GzipInputStream::close()
+{
+ if (closed)
+ return;
+
+ int zerr = inflateEnd(&d_stream);
+ if (zerr != Z_OK) {
+ printf("inflateEnd: Some kind of problem: %d\n", zerr);
+ }
+
+ if ( srcBuf ) {
+ delete[] srcBuf;
+ srcBuf = nullptr;
+ }
+ if ( outputBuf ) {
+ delete[] outputBuf;
+ outputBuf = nullptr;
+ }
+ closed = true;
+}
+
+/**
+ * Reads the next byte of data from the input stream. -1 if EOF
+ */
+int GzipInputStream::get()
+{
+ int ch = -1;
+ if (closed) {
+ // leave return value -1
+ }
+ else if (!loaded && !load()) {
+ closed=true;
+ } else {
+ loaded = true;
+
+ if ( outputBufPos >= outputBufLen ) {
+ // time to read more, if we can
+ fetchMore();
+ }
+
+ if ( outputBufPos < outputBufLen ) {
+ ch = (int)outputBuf[outputBufPos++];
+ }
+ }
+
+ return ch;
+}
+
+#define FTEXT 0x01
+#define FHCRC 0x02
+#define FEXTRA 0x04
+#define FNAME 0x08
+#define FCOMMENT 0x10
+
+bool GzipInputStream::load()
+{
+ crc = crc32(0L, Z_NULL, 0);
+
+ std::vector<Byte> inputBuf;
+ while (true)
+ {
+ int ch = source.get();
+ if (ch<0)
+ break;
+ inputBuf.push_back(static_cast<Byte>(ch & 0xff));
+ }
+ long inputBufLen = inputBuf.size();
+
+ if (inputBufLen < 19) //header + tail + 1
+ {
+ return false;
+ }
+
+ srcLen = inputBuf.size();
+ srcBuf = new (std::nothrow) Byte [srcLen];
+ if (!srcBuf) {
+ return false;
+ }
+
+ outputBuf = new (std::nothrow) unsigned char [OUT_SIZE];
+ if ( !outputBuf ) {
+ delete[] srcBuf;
+ srcBuf = nullptr;
+ return false;
+ }
+ outputBufLen = 0; // Not filled in yet
+
+ std::vector<unsigned char>::iterator iter;
+ Bytef *p = srcBuf;
+ for (iter=inputBuf.begin() ; iter != inputBuf.end() ; ++iter)
+ {
+ *p++ = *iter;
+ }
+
+ int headerLen = 10;
+
+ //Magic
+ //int val = (int)srcBuf[0];
+ ////printf("val:%x\n", val);
+ //val = (int)srcBuf[1];
+ ////printf("val:%x\n", val);
+
+ ////Method
+ //val = (int)srcBuf[2];
+ ////printf("val:%x\n", val);
+
+ //flags
+ int flags = static_cast<int>(srcBuf[3]);
+
+ ////time
+ //val = (int)srcBuf[4];
+ //val = (int)srcBuf[5];
+ //val = (int)srcBuf[6];
+ //val = (int)srcBuf[7];
+
+ ////xflags
+ //val = (int)srcBuf[8];
+ ////OS
+ //val = (int)srcBuf[9];
+
+// if ( flags & FEXTRA ) {
+// headerLen += 2;
+// int xlen =
+// TODO deal with optional header parts
+// }
+ if ( flags & FNAME ) {
+ int cur = 10;
+ while ( srcBuf[cur] )
+ {
+ cur++;
+ headerLen++;
+ }
+ headerLen++;
+ }
+
+
+ srcCrc = ((0x0ff & srcBuf[srcLen - 5]) << 24)
+ | ((0x0ff & srcBuf[srcLen - 6]) << 16)
+ | ((0x0ff & srcBuf[srcLen - 7]) << 8)
+ | ((0x0ff & srcBuf[srcLen - 8]) << 0);
+ //printf("srcCrc:%lx\n", srcCrc);
+
+ srcSiz = ((0x0ff & srcBuf[srcLen - 1]) << 24)
+ | ((0x0ff & srcBuf[srcLen - 2]) << 16)
+ | ((0x0ff & srcBuf[srcLen - 3]) << 8)
+ | ((0x0ff & srcBuf[srcLen - 4]) << 0);
+ //printf("srcSiz:%lx/%ld\n", srcSiz, srcSiz);
+
+ //outputBufLen = srcSiz + srcSiz/100 + 14;
+
+ unsigned char *data = srcBuf + headerLen;
+ unsigned long dataLen = srcLen - (headerLen + 8);
+ //printf("%x %x\n", data[0], data[dataLen-1]);
+
+ d_stream.zalloc = (alloc_func)nullptr;
+ d_stream.zfree = (free_func)nullptr;
+ d_stream.opaque = (voidpf)nullptr;
+ d_stream.next_in = data;
+ d_stream.avail_in = dataLen;
+ d_stream.next_out = outputBuf;
+ d_stream.avail_out = OUT_SIZE;
+
+ int zerr = inflateInit2(&d_stream, -MAX_WBITS);
+ if ( zerr == Z_OK )
+ {
+ zerr = fetchMore();
+ } else {
+ printf("inflateInit2: Some kind of problem: %d\n", zerr);
+ }
+
+
+ return (zerr == Z_OK) || (zerr == Z_STREAM_END);
+}
+
+
+int GzipInputStream::fetchMore()
+{
+ // TODO assumes we aren't called till the buffer is empty
+ d_stream.next_out = outputBuf;
+ d_stream.avail_out = OUT_SIZE;
+ outputBufLen = 0;
+ outputBufPos = 0;
+
+ int zerr = inflate( &d_stream, Z_SYNC_FLUSH );
+ if ( zerr == Z_OK || zerr == Z_STREAM_END ) {
+ outputBufLen = OUT_SIZE - d_stream.avail_out;
+ if ( outputBufLen ) {
+ crc = crc32(crc, const_cast<const Bytef *>(outputBuf), outputBufLen);
+ }
+ //printf("crc:%lx\n", crc);
+// } else if ( zerr != Z_STREAM_END ) {
+// // TODO check to be sure this won't happen for partial end reads
+// printf("inflate: Some kind of problem: %d\n", zerr);
+ }
+
+ return zerr;
+}
+
+//#########################################################################
+//# G Z I P O U T P U T S T R E A M
+//#########################################################################
+
+/**
+ *
+ */
+GzipOutputStream::GzipOutputStream(OutputStream &destinationStream)
+ : BasicOutputStream(destinationStream)
+{
+
+ totalIn = 0;
+ totalOut = 0;
+ crc = crc32(0L, Z_NULL, 0);
+
+ //Gzip header
+ destination.put(0x1f);
+ destination.put(0x8b);
+
+ //Say it is compressed
+ destination.put(Z_DEFLATED);
+
+ //flags
+ destination.put(0);
+
+ //time
+ destination.put(0);
+ destination.put(0);
+ destination.put(0);
+ destination.put(0);
+
+ //xflags
+ destination.put(0);
+
+ //OS code - from zutil.h
+ //destination.put(OS_CODE);
+ //apparently, we should not explicitly include zutil.h
+ destination.put(0);
+
+}
+
+/**
+ *
+ */
+GzipOutputStream::~GzipOutputStream()
+{
+ close();
+}
+
+/**
+ * Closes this output stream and releases any system resources
+ * associated with this stream.
+ */
+void GzipOutputStream::close()
+{
+ if (closed)
+ return;
+
+ flush();
+
+ //# Send the CRC
+ uLong outlong = crc;
+ for (int n = 0; n < 4; n++)
+ {
+ destination.put(static_cast<char>(outlong & 0xff));
+ outlong >>= 8;
+ }
+ //# send the file length
+ outlong = totalIn & 0xffffffffL;
+ for (int n = 0; n < 4; n++)
+ {
+ destination.put(static_cast<char>(outlong & 0xff));
+ outlong >>= 8;
+ }
+
+ destination.close();
+ closed = true;
+}
+
+/**
+ * Flushes this output stream and forces any buffered output
+ * bytes to be written out.
+ */
+void GzipOutputStream::flush()
+{
+ if (closed || inputBuf.empty())
+ {
+ return;
+ }
+
+ uLong srclen = inputBuf.size();
+ Bytef *srcbuf = new (std::nothrow) Bytef [srclen];
+ if (!srcbuf)
+ {
+ return;
+ }
+
+ uLong destlen = srclen;
+ Bytef *destbuf = new (std::nothrow) Bytef [(destlen + (srclen/100) + 13)];
+ if (!destbuf)
+ {
+ delete[] srcbuf;
+ return;
+ }
+
+ std::vector<unsigned char>::iterator iter;
+ Bytef *p = srcbuf;
+ for (iter=inputBuf.begin() ; iter != inputBuf.end() ; ++iter)
+ *p++ = *iter;
+
+ crc = crc32(crc, const_cast<const Bytef *>(srcbuf), srclen);
+
+ int zerr = compress(destbuf, static_cast<uLongf *>(&destlen), srcbuf, srclen);
+ if (zerr != Z_OK)
+ {
+ printf("Some kind of problem\n");
+ }
+
+ totalOut += destlen;
+ //skip the redundant zlib header and checksum
+ for (uLong i=2; i<destlen-4 ; i++)
+ {
+ destination.put((int)destbuf[i]);
+ }
+
+ destination.flush();
+
+ inputBuf.clear();
+ delete[] srcbuf;
+ delete[] destbuf;
+}
+
+
+
+/**
+ * Writes the specified byte to this output stream.
+ */
+int GzipOutputStream::put(char ch)
+{
+ if (closed)
+ {
+ //probably throw an exception here
+ return -1;
+ }
+
+
+ //Add char to buffer
+ inputBuf.push_back(ch);
+ totalIn++;
+ return 1;
+}
+
+
+
+} // namespace IO
+} // namespace Inkscape
+
+
+//#########################################################################
+//# E N D O F F I L E
+//#########################################################################
+
+/*
+ Local Variables:
+ mode:c++
+ c-file-style:"stroustrup"
+ c-file-offsets:((innamespace . 0)(inline-open . 0))
+ indent-tabs-mode:nil
+ fill-column:99
+ End:
+*/
+// vim: expandtab:shiftwidth=4:tabstop=8:softtabstop=4 :
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