Add Windows API plugin

[nemequ]

http://msdn.microsoft.com/en-us/library/windows/hardware/ff552127%28v=vs.85%29.aspx (RtlCompressBuffer)

Depends on #38.

[nemequ]

I've added a Windows plugin to the wip/windows branch. There is still some work to be done (which is hard for me to do without a Windows development environment), but it should be pretty straightforward.

Basically, someone just needs to get it to compile, then provide more realistic implementations of the get_max_compressed_size functions.

Just in case I end up deleting the branch, here is the diff:

diff --git a/docs/index.md b/docs/index.md
index efe7167..ef38773 100644
--- a/docs/index.md
+++ b/docs/index.md
@@ -60,6 +60,7 @@ Squash currently contains plugins for the following libraries:
 - [QuickLZ](@ref md_plugins_quicklz_quicklz)
 - [Snappy](@ref md_plugins_snappy_snappy)
 - [wfLZ](@ref md_plugins_wflz_wflz)
+- [Windows](@ref md_plugins_windows_windows)
 - [yalz77](@ref md_plugins_yalz77_yalz77)
 - [zlib](@ref md_plugins_zlib_zlib)
 - [zlib-ng](@ref md_plugins_zlib-ng_zlib-ng)
diff --git a/plugins/CMakeLists.txt b/plugins/CMakeLists.txt
index f4a4a4e..21443fa 100644
--- a/plugins/CMakeLists.txt
+++ b/plugins/CMakeLists.txt
@@ -27,6 +27,7 @@ set (plugins_available
   quicklz
   snappy
   wflz
+  windows
   yalz77
   zlib
   zlib-ng
diff --git a/plugins/windows/CMakeLists.txt b/plugins/windows/CMakeLists.txt
new file mode 100644
index 0000000..b35ba3c
--- /dev/null
+++ b/plugins/windows/CMakeLists.txt
@@ -0,0 +1,13 @@
+include (SquashPlugin)
+
+check_include_file("Ntifs.h" HAVE_NTIFS_H)
+if(HAVE_NTIFS_H)
+  set(SQUASH_WINDOWS_ENABLED_DEFAULT "")
+else()
+  set(SQUASH_WINDOWS_ENABLED_DEFAULT "DEFAULT_DISABLED")
+endif(HAVE_NTIFS_H)
+
+squash_plugin (
+  NAME windows
+  ${SQUASH_WINDOWS_ENABLED_DEFAULT}
+  SOURCES squash-windows.c)
diff --git a/plugins/windows/squash-windows.c b/plugins/windows/squash-windows.c
new file mode 100644
index 0000000..03280e7
--- /dev/null
+++ b/plugins/windows/squash-windows.c
@@ -0,0 +1,194 @@
+/* Copyright (c) 2016 The Squash Authors
+ *
+ * Permission is hereby granted, free of charge, to any person
+ * obtaining a copy of this software and associated documentation
+ * files (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use, copy,
+ * modify, merge, publish, distribute, sublicense, and/or sell copies
+ * of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ *
+ * Authors:
+ *   Evan Nemerson <evan@nemerson.com>
+ */
+
+#include <assert.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#include <Ntifs.h>
+
+#include <squash/squash.h>
+
+SQUASH_PLUGIN_EXPORT
+SquashStatus squash_plugin_init_codec (SquashCodec* codec, SquashCodecImpl* impl);
+
+static size_t
+squash_windows_lznt1_get_max_compressed_size (SquashCodec* codec, size_t uncompressed_size) {
+  return uncompressed_size * 2 + 256;
+}
+
+static size_t
+squash_windows_xpress_get_max_compressed_size (SquashCodec* codec, size_t uncompressed_size) {
+  return uncompressed_size * 2 + 256;
+}
+
+static size_t
+squash_windows_xpress_huffman_get_max_compressed_size (SquashCodec* codec, size_t uncompressed_size) {
+  return uncompressed_size * 2 + 256;
+}
+
+enum SquashWindowsOptIndex {
+  SQUASH_WINDOWS_OPT_LEVEL = 0
+};
+
+static SquashOptionInfo squash_windows_options[] = {
+  { "level",
+    SQUASH_OPTION_TYPE_RANGE_INT,
+    .info.range_int = {
+      .min = 1,
+      .max = 2 },
+    .default_value.int_value = 1 },
+};
+
+static USHORT squash_windows_get_format_from_codec (SquashCodec* codec) {
+  const char* name = squash_codec_get_name (codec);
+
+  if (name[0] == 'l')
+    return COMPRESSION_FORMAT_LZNT1;
+  else if (name[6] == '-')
+    return COMPRESSION_FORMAT_XPRESS_HUFF;
+  else
+    return COMPRESSION_FORMAT_XPRESS;
+}
+
+static SquashStatus
+squash_windows_compress_buffer (SquashCodec* codec,
+                                size_t* compressed_size,
+                                uint8_t compressed[SQUASH_ARRAY_PARAM(*compressed_size)],
+                                size_t uncompressed_size,
+                                const uint8_t uncompressed[SQUASH_ARRAY_PARAM(uncompressed_size)],
+                                SquashOptions* options) {
+  const USHORT engine = squash_options_get_int_at (options, codec, SQUASH_ZLIB_OPT_LEVEL) == 1 ?
+    COMPRESSION_ENGINE_STANDARD : COMPRESSION_ENGINE_MAXIMUM;
+  const USHORT format = squash_windows_get_format_from_codec (codec);
+  const USHORT format_and_engine = format | engine;
+  uint8_t* workmem = NULL;
+  ULONG workmem_size;
+  NTSTATUS r;
+  ULONG out_size;
+
+#if ULONG_MAX < SIZE_MAX
+  if (SQUASH_UNLIKELY(ULONG_MAX < *compressed_size) ||
+      SQUASH_UNLIKELY(ULONG_MAX < decompressed_size))
+    return squash_error (SQUASH_RANGE);
+#endif
+
+  r = RtlGetCompressionWorkSpaceSize (format_and_engine, &workmem_size, NULL);
+  if (SQUASH_UNLIKELY(r != STATUS_SUCCESS))
+    return squash_error (SQUASH_FAILED);
+
+  workmem = squash_malloc(workmem_size);
+  if (SQUASH_UNLIKELY(workmem == NULL))
+    return squash_error (SQUASH_MEMORY);
+
+  r = RtlCompressBuffer (format_and_engine,
+                         (PUCHAR) uncompressed, (ULONG) uncompressed_size,
+                         (PUCHAR) compressed, (ULONG) *compressed_size,
+                         4096, &out_size, workmem);
+
+  squash_free (workmem);
+
+  if (SQUASH_UNLIKELY(r != STATUS_SUCCCESS)) {
+    switch (r) {
+      case STATUS_BUFFER_ALL_ZEROS:
+        break;
+      case STATUS_BUFFER_TOO_SMALL:
+        return squash_error (SQUASH_BUFFER_FULL);
+      default:
+        return squash_error (SQUASH_FAILED);
+    }
+  }
+
+#if SIZE_MAX < ULONG_MAX
+  if (SQUASH_UNLIKELY(SIZE_MAX < out_size))
+    return squash_error (SQUASH_RANGE);
+#endif
+
+  *compressed_size = (size_t) out_size;
+
+  return SQUASH_OK;
+}
+
+static SquashStatus
+squash_windows_decompress_buffer (SquashCodec* codec,
+                                  size_t* decompressed_size,
+                                  uint8_t decompressed[SQUASH_ARRAY_PARAM(*decompressed_size)],
+                                  size_t compressed_size,
+                                  const uint8_t compressed[SQUASH_ARRAY_PARAM(compressed_size)],
+                                  SquashOptions* options) {
+  const USHORT format = squash_windows_get_format_from_codec (codec);
+  ULONG out_size;
+  NTSTATUS r;
+
+#if ULONG_MAX < SIZE_MAX
+  if (SQUASH_UNLIKELY(ULONG_MAX < compressed_size) ||
+      SQUASH_UNLIKELY(ULONG_MAX < *decompressed_size))
+    return squash_error (SQUASH_RANGE);
+#endif
+
+  r = RtlDecompressBuffer(format,
+                          (PUCHAR) decompressed, (ULONG) *decompressed_size,
+                          (PUCHAR) compressed, (ULONG) compressed_size,
+                          &out_size);
+
+#if SIZE_MAX < ULONG_MAX
+  if (SQUASH_UNLIKELY(SIZE_MAX < out_size))
+    return squash_error (SQUASH_RANGE);
+#endif
+
+  if (SQUASH_UNLIKELY(r != STATUS_SUCCESS)) {
+    switch (r) {
+      case STATUS_BAD_COMPRESSION_BUFFER:
+        return squash_error (SQUASH_BUFFER_FULL);
+      default:
+        return squash_error (SQUASH_FAILED);
+    }
+  }
+
+  *decompressed_size = (size_t) out_size;
+
+  return SQUASH_OK;
+}
+
+SquashStatus
+squash_plugin_init_codec (SquashCodec* codec, SquashCodecImpl* impl) {
+  const char* name = squash_codec_get_name (codec);
+
+  if (strcmp ("lznt1", name) == 0)
+    impl->get_max_compressed_size = squash_windows_lznt1_get_max_compressed_size;
+  else if (strcmp ("xpress", name) == 0)
+    impl->get_max_compressed_size = squash_windows_xpress_get_max_compressed_size;
+  else if (strcmp ("xpress-huffman", name) == 0)
+    impl->get_max_compressed_size = squash_windows_xpress_huffman_get_max_compressed_size;
+  else
+    return squash_error (SQUASH_UNABLE_TO_LOAD);
+
+  impl->options = squash_windows_options;
+  impl->decompress_buffer = squash_windows_decompress_buffer;
+  impl->compress_buffer = squash_windows_compress_buffer;
+
+  return SQUASH_OK;
+}
diff --git a/plugins/windows/squash.ini b/plugins/windows/squash.ini
new file mode 100644
index 0000000..7ebb826
--- /dev/null
+++ b/plugins/windows/squash.ini
@@ -0,0 +1,5 @@
+license=Proprietary
+
+[lznt1]
+[xpress]
+[xpress-huffman]
diff --git a/plugins/windows/windows.md b/plugins/windows/windows.md
new file mode 100644
index 0000000..10715df
--- /dev/null
+++ b/plugins/windows/windows.md
@@ -0,0 +1,29 @@
+# windows Plugin #
+
+This plugin uses the Windows compression API (RtlCompressBuffer et. al.).
+
+For more information about this API, see the
+[RtlCompressBuffer documentation](https://msdn.microsoft.com/en-us/library/windows/hardware/ff552127(v=vs.85).aspx)
+
+Note: this plugin is only available on Windows.  For a cross-platform
+implementation of LZNT1 and Xpress-huffman, see the ms-compress
+plugin.
+
+## Codecs ##
+
+- **lznt1** — LZNT1 data.
+- **xpress** — Xpress data.
+- **xpress-huffman** — Xpress-huffman data.
+
+## Options ##
+
+### Compression Only ###
+
+- **level** (integer, 1 or 2, default 1): whether to use the standard
+  or maximume compression engine.
+
+## License ##
+
+The windows plugin is licensed under the
+[MIT License](http://opensource.org/licenses/MIT).  The Windows API is
+proprietary.

[nemequ]

Note that the random-data test provides a convenient way to figure out those get_max_compressed_size functions. Just do something like:

./tests/test-squash --log-visible debug --show-stderr --param codec windows:$codec /random

Where $codec is lznt1, xpress, and xpress-huffman.