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* - Simplify offs[] index in construct()
* - Add input size and checking, using longjmp() to
* maintain easy readability
* - Use short data type for large arrays
* - Use pointers instead of long to specify source and
* destination sizes to avoid arbitrary 4 GB limits
* 1.2 17 Mar 2002 - Add faster version of decode(), doubles speed (!),
* but leave simple version for readabilty
* - Make sure invalid distances detected if pointers
* are 16 bits
* - Fix fixed codes table error
* - Provide a scanning mode for determining size of
* uncompressed data
* 1.3 20 Mar 2002 - Go back to lengths for puff() parameters [Gailly]
* - Add a puff.h file for the interface
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* - Simplify offs[] index in construct()
* - Add input size and checking, using longjmp() to
* maintain easy readability
* - Use short data type for large arrays
* - Use pointers instead of long to specify source and
* destination sizes to avoid arbitrary 4 GB limits
* 1.2 17 Mar 2002 - Add faster version of decode(), doubles speed (!),
* but leave simple version for readability
* - Make sure invalid distances detected if pointers
* are 16 bits
* - Fix fixed codes table error
* - Provide a scanning mode for determining size of
* uncompressed data
* 1.3 20 Mar 2002 - Go back to lengths for puff() parameters [Gailly]
* - Add a puff.h file for the interface
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* - If there are only literal codes and no lengths, then there are no distance
* codes. This is represented by one distance code with zero bits.
*
* - The list of up to 286 length/literal lengths and up to 30 distance lengths
* are themselves compressed using Huffman codes and run-length encoding. In
* the list of code lengths, a 0 symbol means no code, a 1..15 symbol means
* that length, and the symbols 16, 17, and 18 are run-length instructions.
* Each of 16, 17, and 18 are follwed by extra bits to define the length of
* the run. 16 copies the last length 3 to 6 times. 17 represents 3 to 10
* zero lengths, and 18 represents 11 to 138 zero lengths. Unused symbols
* are common, hence the special coding for zero lengths.
*
* - The symbols for 0..18 are Huffman coded, and so that code must be
* described first. This is simply a sequence of up to 19 three-bit values
* representing no code (0) or the code length for that symbol (1..7).
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* - If there are only literal codes and no lengths, then there are no distance
* codes. This is represented by one distance code with zero bits.
*
* - The list of up to 286 length/literal lengths and up to 30 distance lengths
* are themselves compressed using Huffman codes and run-length encoding. In
* the list of code lengths, a 0 symbol means no code, a 1..15 symbol means
* that length, and the symbols 16, 17, and 18 are run-length instructions.
* Each of 16, 17, and 18 are followed by extra bits to define the length of
* the run. 16 copies the last length 3 to 6 times. 17 represents 3 to 10
* zero lengths, and 18 represents 11 to 138 zero lengths. Unused symbols
* are common, hence the special coding for zero lengths.
*
* - The symbols for 0..18 are Huffman coded, and so that code must be
* described first. This is simply a sequence of up to 19 three-bit values
* representing no code (0) or the code length for that symbol (1..7).
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