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Diffstat (limited to 'src/libs/7zip/unix/CPP/7zip/Compress/ZlibDecoder.cpp')
-rw-r--r--src/libs/7zip/unix/CPP/7zip/Compress/ZlibDecoder.cpp89
1 files changed, 89 insertions, 0 deletions
diff --git a/src/libs/7zip/unix/CPP/7zip/Compress/ZlibDecoder.cpp b/src/libs/7zip/unix/CPP/7zip/Compress/ZlibDecoder.cpp
new file mode 100644
index 000000000..90d6715db
--- /dev/null
+++ b/src/libs/7zip/unix/CPP/7zip/Compress/ZlibDecoder.cpp
@@ -0,0 +1,89 @@
+// ZlibDecoder.cpp
+
+#include "StdAfx.h"
+
+#include "../Common/StreamUtils.h"
+
+#include "ZlibDecoder.h"
+
+namespace NCompress {
+namespace NZlib {
+
+#define DEFLATE_TRY_BEGIN try {
+#define DEFLATE_TRY_END } catch(...) { return S_FALSE; }
+
+#define ADLER_MOD 65521
+#define ADLER_LOOP_MAX 5550
+
+UInt32 Adler32_Update(UInt32 adler, const Byte *buf, size_t size)
+{
+ UInt32 a = adler & 0xFFFF;
+ UInt32 b = (adler >> 16) & 0xFFFF;
+ while (size > 0)
+ {
+ unsigned curSize = (size > ADLER_LOOP_MAX) ? ADLER_LOOP_MAX : (unsigned )size;
+ unsigned i;
+ for (i = 0; i < curSize; i++)
+ {
+ a += buf[i];
+ b += a;
+ }
+ buf += curSize;
+ size -= curSize;
+ a %= ADLER_MOD;
+ b %= ADLER_MOD;
+ }
+ return (b << 16) + a;
+}
+
+STDMETHODIMP COutStreamWithAdler::Write(const void *data, UInt32 size, UInt32 *processedSize)
+{
+ HRESULT result = _stream->Write(data, size, &size);
+ _adler = Adler32_Update(_adler, (const Byte *)data, size);
+ if (processedSize != NULL)
+ *processedSize = size;
+ return result;
+}
+
+STDMETHODIMP CDecoder::Code(ISequentialInStream *inStream, ISequentialOutStream *outStream,
+ const UInt64 *inSize, const UInt64 *outSize, ICompressProgressInfo *progress)
+{
+ DEFLATE_TRY_BEGIN
+ if (!AdlerStream)
+ AdlerStream = AdlerSpec = new COutStreamWithAdler;
+ if (!DeflateDecoder)
+ {
+ DeflateDecoderSpec = new NDeflate::NDecoder::CCOMCoder;
+ DeflateDecoderSpec->ZlibMode = true;
+ DeflateDecoder = DeflateDecoderSpec;
+ }
+
+ Byte buf[2];
+ RINOK(ReadStream_FALSE(inStream, buf, 2));
+ int method = buf[0] & 0xF;
+ if (method != 8)
+ return S_FALSE;
+ // int dicSize = buf[0] >> 4;
+ if ((((UInt32)buf[0] << 8) + buf[1]) % 31 != 0)
+ return S_FALSE;
+ if ((buf[1] & 0x20) != 0) // dictPresent
+ return S_FALSE;
+ // int level = (buf[1] >> 6);
+
+ AdlerSpec->SetStream(outStream);
+ AdlerSpec->Init();
+ HRESULT res = DeflateDecoder->Code(inStream, AdlerStream, inSize, outSize, progress);
+ AdlerSpec->ReleaseStream();
+
+ if (res == S_OK)
+ {
+ const Byte *p = DeflateDecoderSpec->ZlibFooter;
+ UInt32 adler = ((UInt32)p[0] << 24) | ((UInt32)p[1] << 16) | ((UInt32)p[2] << 8) | p[3];
+ if (adler != AdlerSpec->GetAdler())
+ return S_FALSE;
+ }
+ return res;
+ DEFLATE_TRY_END
+}
+
+}}