7 files changed, 248 insertions, 232 deletions

diff --git a/src/lib/compression/bzip2/bzip2.cpp b/src/lib/compression/bzip2/bzip2.cpp
index 565eb09fc..1d1af7e29 100644
--- a/src/lib/compression/bzip2/bzip2.cpp
+++ b/src/lib/compression/bzip2/bzip2.cpp
@@ -8,6 +8,7 @@
 */
 
 #include <botan/bzip2.h>
+#include <botan/exceptn.h>
 #include <botan/internal/compress_utils.h>
 
 #define BZ_NO_STDIO
@@ -15,8 +16,6 @@
 
 namespace Botan {
 
-BOTAN_REGISTER_COMPRESSION(Bzip2_Compression, Bzip2_Decompression);
-
 namespace {
 
 class Bzip2_Stream : public Zlib_Style_Stream<bz_stream, char>
diff --git a/src/lib/compression/compress_utils.cpp b/src/lib/compression/compress_utils.cpp
new file mode 100644
index 000000000..2af629b9c
--- /dev/null
+++ b/src/lib/compression/compress_utils.cpp
@@ -0,0 +1,189 @@
+/*
+* Compression Utils
+* (C) 2014,2016 Jack Lloyd
+*
+* Botan is released under the Simplified BSD License (see license.txt)
+*/
+
+#include <botan/internal/compress_utils.h>
+#include <botan/exceptn.h>
+
+namespace Botan {
+
+void* Compression_Alloc_Info::do_malloc(size_t n, size_t size)
+   {
+   const size_t total_size = n * size;
+
+   BOTAN_ASSERT_EQUAL(total_size / size, n, "Overflow check");
+
+   // TODO maximum length check here?
+
+   void* ptr = std::malloc(total_size);
+
+   /*
+   * Return null rather than throwing here as we are being called by a
+   * C library and it may not be possible for an exception to unwind
+   * the call stack from here. The compression library is expecting a
+   * function written in C and a null return on error, which it will
+   * send upwards to the compression wrappers.
+   */
+
+   if(ptr)
+      {
+      std::memset(ptr, 0, total_size);
+      m_current_allocs[ptr] = total_size;
+      }
+
+   return ptr;
+   }
+
+void Compression_Alloc_Info::do_free(void* ptr)
+   {
+   if(ptr)
+      {
+      auto i = m_current_allocs.find(ptr);
+
+      if(i == m_current_allocs.end())
+         throw Exception("Compression_Alloc_Info::free got pointer not allocated by us");
+
+      zero_mem(ptr, i->second);
+      std::free(ptr);
+      m_current_allocs.erase(i);
+      }
+   }
+
+void Stream_Compression::clear()
+   {
+   m_stream.reset();
+   }
+
+void Stream_Compression::start(size_t level)
+   {
+   m_stream.reset(make_stream(level));
+   }
+
+void Stream_Compression::process(secure_vector<byte>& buf, size_t offset, u32bit flags)
+   {
+   BOTAN_ASSERT(m_stream, "Initialized");
+   BOTAN_ASSERT(buf.size() >= offset, "Offset is sane");
+
+   if(m_buffer.size() < buf.size() + offset)
+      m_buffer.resize(buf.size() + offset);
+
+   // If the output buffer has zero length, .data() might return nullptr. This would
+   // make some compression algorithms (notably those provided by zlib) fail.
+   // Any small positive value works fine, but we choose 32 as it is the smallest power
+   // of two that is large enough to hold all the headers and trailers of the common
+   // formats, preventing further resizings to make room for output data.
+   if(m_buffer.size() == 0)
+      m_buffer.resize(32);
+
+   m_stream->next_in(buf.data() + offset, buf.size() - offset);
+   m_stream->next_out(m_buffer.data() + offset, m_buffer.size() - offset);
+
+   while(true)
+      {
+      m_stream->run(flags);
+
+      if(m_stream->avail_out() == 0)
+         {
+         const size_t added = 8 + m_buffer.size();
+         m_buffer.resize(m_buffer.size() + added);
+         m_stream->next_out(m_buffer.data() + m_buffer.size() - added, added);
+         }
+      else if(m_stream->avail_in() == 0)
+         {
+         m_buffer.resize(m_buffer.size() - m_stream->avail_out());
+         break;
+         }
+      }
+
+   copy_mem(m_buffer.data(), buf.data(), offset);
+   buf.swap(m_buffer);
+   }
+
+void Stream_Compression::update(secure_vector<byte>& buf, size_t offset, bool flush)
+   {
+   BOTAN_ASSERT(m_stream, "Initialized");
+   process(buf, offset, flush ? m_stream->flush_flag() : m_stream->run_flag());
+   }
+
+void Stream_Compression::finish(secure_vector<byte>& buf, size_t offset)
+   {
+   BOTAN_ASSERT(m_stream, "Initialized");
+   process(buf, offset, m_stream->finish_flag());
+   clear();
+   }
+
+void Stream_Decompression::clear()
+   {
+   m_stream.reset();
+   }
+
+void Stream_Decompression::start()
+   {
+   m_stream.reset(make_stream());
+   }
+
+void Stream_Decompression::process(secure_vector<byte>& buf, size_t offset, u32bit flags)
+   {
+   BOTAN_ASSERT(m_stream, "Initialized");
+   BOTAN_ASSERT(buf.size() >= offset, "Offset is sane");
+
+   if(m_buffer.size() < buf.size() + offset)
+      m_buffer.resize(buf.size() + offset);
+
+   m_stream->next_in(buf.data() + offset, buf.size() - offset);
+   m_stream->next_out(m_buffer.data() + offset, m_buffer.size() - offset);
+
+   while(true)
+      {
+      const bool stream_end = m_stream->run(flags);
+
+      if(stream_end)
+         {
+         if(m_stream->avail_in() == 0) // all data consumed?
+            {
+            m_buffer.resize(m_buffer.size() - m_stream->avail_out());
+            clear();
+            break;
+            }
+
+         // More data follows: try to process as a following stream
+         const size_t read = (buf.size() - offset) - m_stream->avail_in();
+         start();
+         m_stream->next_in(buf.data() + offset + read, buf.size() - offset - read);
+         }
+
+      if(m_stream->avail_out() == 0)
+         {
+         const size_t added = 8 + m_buffer.size();
+         m_buffer.resize(m_buffer.size() + added);
+         m_stream->next_out(m_buffer.data() + m_buffer.size() - added, added);
+         }
+      else if(m_stream->avail_in() == 0)
+         {
+         m_buffer.resize(m_buffer.size() - m_stream->avail_out());
+         break;
+         }
+      }
+
+   copy_mem(m_buffer.data(), buf.data(), offset);
+   buf.swap(m_buffer);
+   }
+
+void Stream_Decompression::update(secure_vector<byte>& buf, size_t offset)
+   {
+   process(buf, offset, m_stream->run_flag());
+   }
+
+void Stream_Decompression::finish(secure_vector<byte>& buf, size_t offset)
+   {
+   if(buf.size() != offset || m_stream.get())
+      process(buf, offset, m_stream->finish_flag());
+
+   if(m_stream.get())
+      throw Exception(name() + " finished but not at stream end");
+   }
+
+}
diff --git a/src/lib/compression/compress_utils.h b/src/lib/compression/compress_utils.h
index a60ae3c22..9f6871a0b 100644
--- a/src/lib/compression/compress_utils.h
+++ b/src/lib/compression/compress_utils.h
@@ -9,7 +9,6 @@
 #define BOTAN_COMPRESSION_UTILS_H__
 
 #include <botan/compression.h>
-#include <botan/internal/algo_registry.h>
 #include <memory>
 #include <unordered_map>
 
@@ -85,10 +84,6 @@ class Zlib_Style_Stream : public Compression_Stream
       std::unique_ptr<Compression_Alloc_Info> m_allocs;
    };
 
-#define BOTAN_REGISTER_COMPRESSION(C, D) \
-   BOTAN_REGISTER_T_NOARGS(Compression_Algorithm, C); \
-   BOTAN_REGISTER_T_NOARGS(Decompression_Algorithm, D)
-
 }
 
 #endif
diff --git a/src/lib/compression/compression.cpp b/src/lib/compression/compression.cpp
index f289aa79f..92004a071 100644
--- a/src/lib/compression/compression.cpp
+++ b/src/lib/compression/compression.cpp
@@ -1,233 +1,75 @@
 /*
-* Compression Transform
-* (C) 2014 Jack Lloyd
+* Compression Factory
+* (C) 2014,2016 Jack Lloyd
 *
 * Botan is released under the Simplified BSD License (see license.txt)
 */
 
 #include <botan/compression.h>
-#include <botan/internal/compress_utils.h>
 #include <botan/mem_ops.h>
 #include <cstdlib>
 
-namespace Botan {
-
-void* Compression_Alloc_Info::do_malloc(size_t n, size_t size)
-   {
-   const size_t total_size = n * size;
-
-   BOTAN_ASSERT_EQUAL(total_size / size, n, "Overflow check");
-
-   // TODO maximum length check here?
-
-   void* ptr = std::malloc(total_size);
-
-   /*
-   * Return null rather than throwing here as we are being called by a
-   * C library and it may not be possible for an exception to unwind
-   * the call stack from here. The compression library is expecting a
-   * function written in C and a null return on error, which it will
-   * send upwards to the compression wrappers.
-   */
-
-   if(ptr)
-      {
-      std::memset(ptr, 0, total_size);
-      m_current_allocs[ptr] = total_size;
-      }
-
-   return ptr;
-   }
-
-void Compression_Alloc_Info::do_free(void* ptr)
-   {
-   if(ptr)
-      {
-      auto i = m_current_allocs.find(ptr);
-
-      if(i == m_current_allocs.end())
-         throw Exception("Compression_Alloc_Info::free got pointer not allocated by us");
-
-      zero_mem(ptr, i->second);
-      std::free(ptr);
-      m_current_allocs.erase(i);
-      }
-   }
-
-Compression_Algorithm* make_compressor(const std::string& type)
-   {
-   const std::map<std::string, std::string> trans{
-      {"zlib", "Zlib"},
-      {"deflate", "Deflate"},
-      {"gzip", "Gzip"},
-      {"gz", "Gzip"},
-      {"bzip2", "Bzip2"},
-      {"bz2", "Bzip2"},
-      {"lzma", "LZMA"},
-      {"xz", "LZMA"}};
-
-   auto i = trans.find(type);
-
-   if(i == trans.end())
-      return nullptr;
-
-   const SCAN_Name t_name(i->second + "_Compression");
-   return Algo_Registry<Compression_Algorithm>::global_registry().make(t_name);
-   }
-
-Decompression_Algorithm* make_decompressor(const std::string& type)
-   {
-   const std::map<std::string, std::string> trans{
-      {"zlib", "Zlib"},
-      {"deflate", "Deflate"},
-      {"gzip", "Gzip"},
-      {"gz", "Gzip"},
-      {"bzip2", "Bzip2"},
-      {"bz2", "Bzip2"},
-      {"lzma", "LZMA"},
-      {"xz", "LZMA"}};
-
-   auto i = trans.find(type);
-
-   if(i == trans.end())
-      return nullptr;
-
-   const SCAN_Name t_name(i->second + "_Decompression");
-   return Algo_Registry<Decompression_Algorithm>::global_registry().make(t_name);
-   }
-
-void Stream_Compression::clear()
-   {
-   m_stream.reset();
-   }
-
-void Stream_Compression::start(size_t level)
-   {
-   m_stream.reset(make_stream(level));
-   }
-
-void Stream_Compression::process(secure_vector<byte>& buf, size_t offset, u32bit flags)
-   {
-   BOTAN_ASSERT(m_stream, "Initialized");
-   BOTAN_ASSERT(buf.size() >= offset, "Offset is sane");
-
-   if(m_buffer.size() < buf.size() + offset)
-      m_buffer.resize(buf.size() + offset);
-
-   // If the output buffer has zero length, .data() might return nullptr. This would
-   // make some compression algorithms (notably those provided by zlib) fail.
-   // Any small positive value works fine, but we choose 32 as it is the smallest power
-   // of two that is large enough to hold all the headers and trailers of the common
-   // formats, preventing further resizings to make room for output data.
-   if(m_buffer.size() == 0)
-      m_buffer.resize(32);
-
-   m_stream->next_in(buf.data() + offset, buf.size() - offset);
-   m_stream->next_out(m_buffer.data() + offset, m_buffer.size() - offset);
-
-   while(true)
-      {
-      m_stream->run(flags);
+#if defined(BOTAN_HAS_ZLIB)
+  #include <botan/zlib.h>
+#endif
 
-      if(m_stream->avail_out() == 0)
-         {
-         const size_t added = 8 + m_buffer.size();
-         m_buffer.resize(m_buffer.size() + added);
-         m_stream->next_out(m_buffer.data() + m_buffer.size() - added, added);
-         }
-      else if(m_stream->avail_in() == 0)
-         {
-         m_buffer.resize(m_buffer.size() - m_stream->avail_out());
-         break;
-         }
-      }
+#if defined(BOTAN_HAS_BZIP2)
+  #include <botan/bzip2.h>
+#endif
 
-   copy_mem(m_buffer.data(), buf.data(), offset);
-   buf.swap(m_buffer);
-   }
-
-void Stream_Compression::update(secure_vector<byte>& buf, size_t offset, bool flush)
-   {
-   BOTAN_ASSERT(m_stream, "Initialized");
-   process(buf, offset, flush ? m_stream->flush_flag() : m_stream->run_flag());
-   }
+#if defined(BOTAN_HAS_LZMA)
+  #include <botan/lzma.h>
+#endif
 
-void Stream_Compression::finish(secure_vector<byte>& buf, size_t offset)
-   {
-   BOTAN_ASSERT(m_stream, "Initialized");
-   process(buf, offset, m_stream->finish_flag());
-   clear();
-   }
-
-void Stream_Decompression::clear()
-   {
-   m_stream.reset();
-   }
+namespace Botan {
 
-void Stream_Decompression::start()
+Compression_Algorithm* make_compressor(const std::string& name)
    {
-   m_stream.reset(make_stream());
+#if defined(BOTAN_HAS_ZLIB)
+   if(name == "Zlib" || name == "zlib")
+      return new Zlib_Compression;
+   if(name == "Gzip" || name == "gzip" || name == "gz")
+      return new Gzip_Compression;
+   if(name == "Deflate" || name == "deflate")
+      return new Deflate_Compression;
+#endif
+
+#if defined(BOTAN_HAS_BZIP2)
+   if(name == "bzip2" || name == "bz2" || name == "Bzip2")
+      return new Bzip2_Compression;
+#endif
+
+#if defined(BOTAN_HAS_LZMA)
+   if(name == "lzma" || name == "xz" || name == "LZMA")
+      return new LZMA_Compression;
+#endif
+
+   return nullptr;
    }
 
-void Stream_Decompression::process(secure_vector<byte>& buf, size_t offset, u32bit flags)
+Decompression_Algorithm* make_decompressor(const std::string& name)
    {
-   BOTAN_ASSERT(m_stream, "Initialized");
-   BOTAN_ASSERT(buf.size() >= offset, "Offset is sane");
-
-   if(m_buffer.size() < buf.size() + offset)
-      m_buffer.resize(buf.size() + offset);
-
-   m_stream->next_in(buf.data() + offset, buf.size() - offset);
-   m_stream->next_out(m_buffer.data() + offset, m_buffer.size() - offset);
-
-   while(true)
-      {
-      const bool stream_end = m_stream->run(flags);
-
-      if(stream_end)
-         {
-         if(m_stream->avail_in() == 0) // all data consumed?
-            {
-            m_buffer.resize(m_buffer.size() - m_stream->avail_out());
-            clear();
-            break;
-            }
-
-         // More data follows: try to process as a following stream
-         const size_t read = (buf.size() - offset) - m_stream->avail_in();
-         start();
-         m_stream->next_in(buf.data() + offset + read, buf.size() - offset - read);
-         }
-
-      if(m_stream->avail_out() == 0)
-         {
-         const size_t added = 8 + m_buffer.size();
-         m_buffer.resize(m_buffer.size() + added);
-         m_stream->next_out(m_buffer.data() + m_buffer.size() - added, added);
-         }
-      else if(m_stream->avail_in() == 0)
-         {
-         m_buffer.resize(m_buffer.size() - m_stream->avail_out());
-         break;
-         }
-      }
-
-   copy_mem(m_buffer.data(), buf.data(), offset);
-   buf.swap(m_buffer);
-   }
-
-void Stream_Decompression::update(secure_vector<byte>& buf, size_t offset)
-   {
-   process(buf, offset, m_stream->run_flag());
+#if defined(BOTAN_HAS_ZLIB)
+   if(name == "Zlib" || name == "zlib")
+      return new Zlib_Decompression;
+   if(name == "Gzip" || name == "gzip" || name == "gz")
+      return new Gzip_Decompression;
+   if(name == "Deflate" || name == "deflate")
+      return new Deflate_Decompression;
+#endif
+
+#if defined(BOTAN_HAS_BZIP2)
+   if(name == "bzip2" || name == "bz2" || name == "Bzip2")
+      return new Bzip2_Decompression;
+#endif
+
+#if defined(BOTAN_HAS_LZMA)
+   if(name == "lzma" || name == "xz" || name == "LZMA")
+      return new LZMA_Decompression;
+#endif
+
+   return nullptr;
    }
 
-void Stream_Decompression::finish(secure_vector<byte>& buf, size_t offset)
-   {
-   if(buf.size() != offset || m_stream.get())
-      process(buf, offset, m_stream->finish_flag());
-
-   if(m_stream.get())
-      throw Exception(name() + " finished but not at stream end");
-   }
 
 }
diff --git a/src/lib/compression/compression.h b/src/lib/compression/compression.h
index f135f6d04..693772b6a 100644
--- a/src/lib/compression/compression.h
+++ b/src/lib/compression/compression.h
@@ -9,7 +9,6 @@
 #define BOTAN_COMPRESSION_TRANSFORM_H__
 
 #include <botan/secmem.h>
-#include <botan/scan_name.h>
 
 namespace Botan {
 
@@ -19,8 +18,6 @@ namespace Botan {
 class BOTAN_DLL Compression_Algorithm
    {
    public:
-      typedef SCAN_Name Spec;
-
       /**
       * Begin compressing. Most compression algorithms offer a tunable
       * time/compression tradeoff parameter generally represented by
@@ -67,8 +64,6 @@ class BOTAN_DLL Compression_Algorithm
 class BOTAN_DLL Decompression_Algorithm
    {
    public:
-      typedef SCAN_Name Spec;
-
       /**
       * Begin decompressing.
       * Decompression does not support levels, as compression does.
@@ -108,7 +103,7 @@ BOTAN_DLL Compression_Algorithm* make_compressor(const std::string& type);
 BOTAN_DLL Decompression_Algorithm* make_decompressor(const std::string& type);
 
 /**
-* FIXME add doc
+* Adapts a zlib style API
 */
 class Compression_Stream
    {
@@ -131,7 +126,7 @@ class Compression_Stream
    };
 
 /**
-* FIXME add doc
+* Used to implement compression using Compression_Stream
 */
 class Stream_Compression : public Compression_Algorithm
    {
diff --git a/src/lib/compression/lzma/lzma.cpp b/src/lib/compression/lzma/lzma.cpp
index 18701278d..3831ef68c 100644
--- a/src/lib/compression/lzma/lzma.cpp
+++ b/src/lib/compression/lzma/lzma.cpp
@@ -10,12 +10,11 @@
 
 #include <botan/lzma.h>
 #include <botan/internal/compress_utils.h>
+#include <botan/exceptn.h>
 #include <lzma.h>
 
 namespace Botan {
 
-BOTAN_REGISTER_COMPRESSION(LZMA_Compression, LZMA_Decompression);
-
 namespace {
 
 class LZMA_Stream : public Zlib_Style_Stream<lzma_stream, byte>
diff --git a/src/lib/compression/zlib/zlib.cpp b/src/lib/compression/zlib/zlib.cpp
index 836925a68..27ae6fb20 100644
--- a/src/lib/compression/zlib/zlib.cpp
+++ b/src/lib/compression/zlib/zlib.cpp
@@ -9,15 +9,12 @@
 
 #include <botan/zlib.h>
 #include <botan/internal/compress_utils.h>
+#include <botan/exceptn.h>
 #include <ctime>
 #include <zlib.h>
 
 namespace Botan {
 
-BOTAN_REGISTER_COMPRESSION(Zlib_Compression, Zlib_Decompression);
-BOTAN_REGISTER_COMPRESSION(Gzip_Compression, Gzip_Decompression);
-BOTAN_REGISTER_COMPRESSION(Deflate_Compression, Deflate_Decompression);
-
 namespace {
 
 class Zlib_Stream : public Zlib_Style_Stream<z_stream, Bytef>