Convert compression filters to in-place transforms and refactor

to minimize the amount of logic needed in the files specific to each
library.

3 files changed, 152 insertions, 0 deletions

diff --git a/src/lib/compression/lzma/info.txt b/src/lib/compression/lzma/info.txt
new file mode 100644
index 000000000..1ec668ca8
--- /dev/null
+++ b/src/lib/compression/lzma/info.txt
@@ -0,0 +1,7 @@
+define LZMA_TRANSFORM 20141118
+
+load_on request
+
+<libs>
+all -> lzma
+</libs>
diff --git a/src/lib/compression/lzma/lzma.cpp b/src/lib/compression/lzma/lzma.cpp
new file mode 100644
index 000000000..d145ed305
--- /dev/null
+++ b/src/lib/compression/lzma/lzma.cpp
@@ -0,0 +1,94 @@
+/*
+* Lzma Compressor
+* (C) 2001 Peter J Jones
+*     2001-2007,2014 Jack Lloyd
+*     2006 Matt Johnston
+*     2012 Vojtech Kral
+*
+* Distributed under the terms of the Botan license
+*/
+
+#include <botan/lzma.h>
+#include <botan/internal/comp_util.h>
+#include <lzma.h>
+
+namespace Botan {
+
+namespace {
+
+class LZMA_Stream : public Zlib_Style_Stream<lzma_stream, byte>
+   {
+   public:
+      LZMA_Stream()
+         {
+         streamp()->allocator = new ::lzma_allocator;
+         streamp()->allocator->opaque = alloc();
+         streamp()->allocator->alloc = Compression_Alloc_Info::malloc<size_t>;
+         streamp()->allocator->free = Compression_Alloc_Info::free;
+         }
+
+      ~LZMA_Stream()
+         {
+         ::lzma_end(streamp());
+         delete streamp()->allocator;
+         }
+
+      bool run(u32bit flags) override
+         {
+         lzma_ret rc = ::lzma_code(streamp(), static_cast<lzma_action>(flags));
+
+         if(rc == LZMA_MEM_ERROR)
+            throw std::bad_alloc();
+         else if (rc != LZMA_OK && rc != LZMA_STREAM_END)
+            throw std::runtime_error("Lzma error");
+
+         return (rc == LZMA_STREAM_END);
+         }
+
+      u32bit run_flag() const override { return LZMA_RUN; }
+      u32bit flush_flag() const override { return LZMA_FULL_FLUSH; }
+      u32bit finish_flag() const override { return LZMA_FINISH; }
+   };
+
+class LZMA_Compression_Stream : public LZMA_Stream
+   {
+   public:
+      LZMA_Compression_Stream(size_t level)
+         {
+         lzma_ret rc = ::lzma_easy_encoder(streamp(), level, LZMA_CHECK_CRC64);
+
+         if(rc == LZMA_MEM_ERROR)
+            throw std::bad_alloc();
+         else if(rc != LZMA_OK)
+            throw std::runtime_error("lzma compress initialization failed");
+         }
+   };
+
+class LZMA_Decompression_Stream : public LZMA_Stream
+   {
+   public:
+      LZMA_Decompression_Stream()
+         {
+         lzma_ret rc = ::lzma_stream_decoder(streamp(), UINT64_MAX,
+                                             LZMA_TELL_UNSUPPORTED_CHECK);
+
+         if(rc == LZMA_MEM_ERROR)
+            throw std::bad_alloc();
+         else if(rc != LZMA_OK)
+            throw std::runtime_error("Bad setting in lzma_stream_decoder");
+         }
+   };
+
+}
+
+Compression_Stream* LZMA_Compression::make_stream() const
+   {
+   return new LZMA_Compression_Stream(m_level);
+   }
+
+Compression_Stream* LZMA_Decompression::make_stream() const
+   {
+   return new LZMA_Decompression_Stream;
+   }
+
+}
diff --git a/src/lib/compression/lzma/lzma.h b/src/lib/compression/lzma/lzma.h
new file mode 100644
index 000000000..0761a8194
--- /dev/null
+++ b/src/lib/compression/lzma/lzma.h
@@ -0,0 +1,51 @@
+/*
+* Lzma Compressor
+* (C) 2001 Peter J Jones
+*     2001-2007 Jack Lloyd
+*     2012 Vojtech Kral
+*
+* Distributed under the terms of the Botan license
+*/
+
+#ifndef BOTAN_LZMA_H__
+#define BOTAN_LZMA_H__
+
+#include <botan/compression.h>
+
+namespace Botan {
+
+/**
+* LZMA Compression
+*/
+class BOTAN_DLL LZMA_Compression : public Stream_Compression
+   {
+   public:
+      /**
+      * @param level how much effort to use on compressing (0 to 9);
+      *        higher levels are slower but tend to give better
+      *        compression
+      */
+      LZMA_Compression(size_t level = 6) : m_level(level) {}
+
+      std::string name() const override { return "LZMA_Compression"; }
+
+   private:
+      Compression_Stream* make_stream() const;
+
+      const size_t m_level;
+   };
+
+/**
+* LZMA Deccompression
+*/
+class BOTAN_DLL LZMA_Decompression : public Stream_Decompression
+   {
+   public:
+      std::string name() const override { return "LZMA_Decompression"; }
+   private:
+      Compression_Stream* make_stream() const;
+   };
+
+}
+
+#endif