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diff --git a/tools/src/minilzlib/lzma2dec.h b/tools/src/minilzlib/lzma2dec.h
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+++ b/tools/src/minilzlib/lzma2dec.h
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+/*++
+
+Copyright (c) Alex Ionescu.  All rights reserved.
+
+Module Name:
+
+    lzma2dec.h
+
+Abstract:
+
+    This header file contains C-style data structures and enumerations that map
+    back to the LZMA2 standard. This includes the encoding of the LZMA2 Control
+    Byte and the possible LZMA2 Reset States.
+
+Author:
+
+    Alex Ionescu (@aionescu) 15-Apr-2020 - Initial version
+
+Environment:
+
+    Windows & Linux, user mode and kernel mode.
+
+--*/
+
+#pragma once
+
+//
+// The most complex LZMA sequence possible is a "match" sequence where the
+// the length is > 127 bytes, and the distance is > 127 bytes. This type of
+// sequence starts with {1,1} for "match", followed by {1,1,nnnnnnnn} for
+// "8-bit encoded length", followed by {1,1,1,1,1,1} to select the distance
+// slot (63). That's 18 bits so far, which all come from arithmetic-coded
+// bit trees with various probabilities. The next 26 bits are going to be
+// fixed-probability, meaning that the bit tree is mathematically hardcoded
+// at 50%. Finally, there are the last 4 "align" distance bits which also
+// come from an arithmetic-coded bit tree, bringing the total such bits to
+// 22.
+//
+// Each time we have to "normalize" the arithmetic coder, it consumes an
+// additional byte. Normalization is done whenever we consume more than 8
+// of the high bits of the coder's range (i.e.: below 2^24), so exactly
+// every 8 direct bits (which always halve the range due to their 50%).
+// The other bits can have arbitrary probabilities, but in the worst case
+// we need to normalize the range every n bits. As such, this is a total of
+// 20 worst-case normalization per LZMA sequence. Finally, we do one last
+// normalization at the end of LzDecode, to make sure that the decoder is
+// always in a normalized state. This means that a compressed chunk should
+// be at least 21 bytes if we want to guarantee that LzDecode can never
+// read past the current input stream, and avoid range checking.
+//
+#define LZMA_MAX_SEQUENCE_SIZE              21
+
+//
+// This describes the different ways an LZMA2 control byte can request a reset
+//
+typedef enum _LZMA2_COMPRESSED_RESET_STATE
+{
+    Lzma2NoReset = 0,
+    Lzma2SimpleReset = 1,
+    Lzma2PropertyReset = 2,
+    Lzma2FullReset = 3
+} LZMA2_COMPRESSED_RESET_STATE;
+
+//
+// This describes how an LZMA2 control byte can be parsed
+//
+typedef union _LZMA2_CONTROL_BYTE
+{
+    union
+    {
+        struct
+        {
+            uint8_t ResetState : 2;
+            uint8_t Reserved : 5;
+            uint8_t IsLzma : 1;
+        } Raw;
+        struct
+        {
+            uint8_t RawSize : 5;
+            uint8_t ResetState : 2;
+            uint8_t IsLzma : 1;
+        } Lzma;
+        struct
+        {
+            uint8_t : 7;
+            uint8_t IsLzma : 1;
+        } Common;
+    } u;
+    uint8_t Value;
+} LZMA2_CONTROL_BYTE;
+static_assert(sizeof(LZMA2_CONTROL_BYTE) == 1, "Invalid control byte size");