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MOD: simplified code by removing unnecessary separation between prefi…
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…x_code and prefix_tree
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@ende76
ende76 committed Oct 26, 2015
1 parent 1e90eb5 commit 3540aa1
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Showing 2 changed files with 25 additions and 83 deletions.
106 changes: 24 additions & 82 deletions src/lib.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -87,29 +87,6 @@ enum PrefixCodeKind {
Complex(HSkip),
}

#[derive(Debug, Clone, PartialEq)]
struct PrefixCodeSimple {
n_sym: Option<NSym>,
symbols: Option<Symbols>,
tree_select: Option<TreeSelect>,
}

#[derive(Debug, Clone, PartialEq)]
enum PrefixCode {
Simple(PrefixCodeSimple),
Complex,
}

impl PrefixCode {
fn new_simple(n_sym: Option<NSym>, symbols: Option<Symbols>, tree_select:Option<TreeSelect>) -> PrefixCode {
PrefixCode::Simple(PrefixCodeSimple {
n_sym: n_sym,
symbols: symbols,
tree_select: tree_select,
})
}
}

#[derive(Debug, Clone, PartialEq)]
struct Header {
wbits: Option<WBits>,
Expand Down Expand Up @@ -210,15 +187,6 @@ struct MetaBlockHeader {
n_trees_d: Option<NTrees>,
c_map_d: Option<ContextMap>,
c_map_l: Option<ContextMap>,
prefix_code_block_types_literals: Option<PrefixCode>,
prefix_code_block_counts_literals: Option<PrefixCode>,
prefix_code_block_types_insert_and_copy_lengths: Option<PrefixCode>,
prefix_code_block_counts_insert_and_copy_lengths: Option<PrefixCode>,
prefix_code_block_types_distances: Option<PrefixCode>,
prefix_code_block_counts_distances: Option<PrefixCode>,
prefix_codes_literals: Option<Vec<PrefixCode>>,
prefix_codes_insert_and_copy_lengths: Option<Vec<PrefixCode>>,
prefix_codes_distances: Option<Vec<PrefixCode>>,
}

impl MetaBlockHeader {
Expand All @@ -240,15 +208,6 @@ impl MetaBlockHeader {
n_trees_d: None,
c_map_d: None,
c_map_l: None,
prefix_code_block_types_literals: None,
prefix_code_block_counts_literals: None,
prefix_code_block_types_insert_and_copy_lengths: None,
prefix_code_block_counts_insert_and_copy_lengths: None,
prefix_code_block_types_distances: None,
prefix_code_block_counts_distances: None,
prefix_codes_literals: None,
prefix_codes_insert_and_copy_lengths: None,
prefix_codes_distances: None,
}
}
}
Expand All @@ -271,16 +230,16 @@ enum State {
MLenLiterals(MLenLiterals),
BltypeCodes(HuffmanCodes),
NBltypesL(NBltypes),
PrefixCodeBlockTypesLiterals((PrefixCode, HuffmanCodes)),
PrefixCodeBlockCountsLiterals((PrefixCode, HuffmanCodes)),
PrefixCodeBlockTypesLiterals(HuffmanCodes),
PrefixCodeBlockCountsLiterals(HuffmanCodes),
FirstBlockCountLiterals(BLen),
NBltypesI(NBltypes),
PrefixCodeBlockTypesInsertAndCopyLengths((PrefixCode, HuffmanCodes)),
PrefixCodeBlockCountsInsertAndCopyLengths((PrefixCode, HuffmanCodes)),
PrefixCodeBlockTypesInsertAndCopyLengths(HuffmanCodes),
PrefixCodeBlockCountsInsertAndCopyLengths(HuffmanCodes),
FirstBlockCountInsertAndCopyLengths(BLen),
NBltypesD(NBltypes),
PrefixCodeBlockTypesDistances((PrefixCode, HuffmanCodes)),
PrefixCodeBlockCountsDistances((PrefixCode, HuffmanCodes)),
PrefixCodeBlockTypesDistances(HuffmanCodes),
PrefixCodeBlockCountsDistances(HuffmanCodes),
FirstBlockCountDistances(BLen),
NPostfix(NPostfix),
NDirect(NDirect),
Expand All @@ -289,9 +248,9 @@ enum State {
NTreesD(NTrees),
ContextMapDistances(ContextMap),
ContextMapLiterals(ContextMap),
PrefixCodesLiterals(Vec<(PrefixCode, HuffmanCodes)>),
PrefixCodesInsertAndCopyLengths(Vec<(PrefixCode, HuffmanCodes)>),
PrefixCodesDistances(Vec<(PrefixCode, HuffmanCodes)>),
PrefixCodesLiterals(Vec<HuffmanCodes>),
PrefixCodesInsertAndCopyLengths(Vec<HuffmanCodes>),
PrefixCodesDistances(Vec<HuffmanCodes>),
DataMetaBlockBegin,
InsertAndCopyLength(InsertAndCopyLength),
InsertLengthAndCopyLength(InsertLengthAndCopyLength),
Expand Down Expand Up @@ -658,7 +617,7 @@ impl<R: Read> Decompressor<R> {
}
}

fn parse_simple_prefix_code(&mut self, alphabet_size: usize) -> Result<(PrefixCode, HuffmanCodes), DecompressorError> {
fn parse_simple_prefix_code(&mut self, alphabet_size: usize) -> Result<HuffmanCodes, DecompressorError> {
let bit_width = 16 - (alphabet_size as u16 - 1).leading_zeros() as usize;

// debug(&format!("Bit Width = {:?}", bit_width));
Expand Down Expand Up @@ -712,12 +671,11 @@ impl<R: Read> Decompressor<R> {
// debug(&format!("Sorted Symbols = {:?}", symbols));
// debug(&format!("Code Lengths = {:?}", code_lengths));

Ok((PrefixCode::new_simple(Some(n_sym as u8), Some(symbols.clone()), tree_select),
huffman::codes_from_lengths_and_symbols(&code_lengths, &symbols)))
Ok(huffman::codes_from_lengths_and_symbols(&code_lengths, &symbols))
}

fn parse_complex_prefix_code(&mut self, h_skip: u8, alphabet_size: usize)
-> Result<(PrefixCode, HuffmanCodes), DecompressorError> {
-> Result<HuffmanCodes, DecompressorError> {
let mut symbols = vec![1, 2, 3, 4, 0, 5, 17, 6, 16, 7, 8, 9, 10, 11, 12, 13, 14, 15];
let bit_lengths_code = {
let bit_lengths_patterns = vec![
Expand Down Expand Up @@ -939,11 +897,10 @@ impl<R: Read> Decompressor<R> {
return Err(DecompressorError::LessThanTwoNonZeroCodeLengths);
}

Ok((PrefixCode::Complex,
huffman::codes_from_lengths(&actual_code_lengths)))
Ok(huffman::codes_from_lengths(&actual_code_lengths))
}

fn parse_prefix_code(&mut self, alphabet_size: usize) -> Result<(PrefixCode, HuffmanCodes), DecompressorError> {
fn parse_prefix_code(&mut self, alphabet_size: usize) -> Result<HuffmanCodes, DecompressorError> {
let prefix_code_kind = match self.parse_prefix_code_kind() {
Ok(kind) => kind,
Err(e) => return Err(e),
Expand Down Expand Up @@ -1143,7 +1100,7 @@ impl<R: Read> Decompressor<R> {

// debug(&format!("Alphabet Size = {:?}", alphabet_size));

let (_, prefix_tree) = match self.parse_prefix_code(alphabet_size) {
let prefix_tree = match self.parse_prefix_code(alphabet_size) {
Ok(v) => v,
Err(e) => return Err(e),
};
Expand Down Expand Up @@ -1879,8 +1836,7 @@ impl<R: Read> Decompressor<R> {
}
}
},
State::PrefixCodeBlockTypesLiterals((prefix_code, prefix_tree)) => {
self.meta_block.header.prefix_code_block_types_literals = Some(prefix_code);
State::PrefixCodeBlockTypesLiterals(prefix_tree) => {
self.meta_block.prefix_tree_block_types_literals = Some(prefix_tree);

// debug(&format!("Prefix Code Block Types Literals = {:?}", self.meta_block.header.prefix_code_block_types_literals));
Expand All @@ -1891,8 +1847,7 @@ impl<R: Read> Decompressor<R> {
Err(e) => return Err(e),
};
},
State::PrefixCodeBlockCountsLiterals((prefix_code, prefix_tree)) => {
self.meta_block.header.prefix_code_block_counts_literals = Some(prefix_code);
State::PrefixCodeBlockCountsLiterals(prefix_tree) => {
self.meta_block.prefix_tree_block_counts_literals = Some(prefix_tree);

// debug(&format!("Prefix Code Block Counts Literals = {:?}", self.meta_block.header.prefix_code_block_counts_literals));
Expand Down Expand Up @@ -1930,8 +1885,7 @@ impl<R: Read> Decompressor<R> {
}
}
},
State::PrefixCodeBlockTypesInsertAndCopyLengths((prefix_code, prefix_tree)) => {
self.meta_block.header.prefix_code_block_types_insert_and_copy_lengths = Some(prefix_code);
State::PrefixCodeBlockTypesInsertAndCopyLengths(prefix_tree) => {
self.meta_block.prefix_tree_block_types_insert_and_copy_lengths = Some(prefix_tree);

// debug(&format!("Prefix Code Block Types Insert And Copy Lengths = {:?}", self.meta_block.header.prefix_code_block_types_insert_and_copy_lengths));
Expand All @@ -1942,8 +1896,7 @@ impl<R: Read> Decompressor<R> {
Err(e) => return Err(e),
};
},
State::PrefixCodeBlockCountsInsertAndCopyLengths((prefix_code, prefix_tree)) => {
self.meta_block.header.prefix_code_block_counts_insert_and_copy_lengths = Some(prefix_code);
State::PrefixCodeBlockCountsInsertAndCopyLengths(prefix_tree) => {
self.meta_block.prefix_tree_block_counts_insert_and_copy_lengths = Some(prefix_tree);

// debug(&format!("Prefix Code Block Counts Insert And Copy Lengths = {:?}", self.meta_block.header.prefix_code_block_counts_insert_and_copy_lengths));
Expand Down Expand Up @@ -1981,8 +1934,7 @@ impl<R: Read> Decompressor<R> {
}
};
},
State::PrefixCodeBlockTypesDistances((prefix_code, prefix_tree)) => {
self.meta_block.header.prefix_code_block_types_distances = Some(prefix_code);
State::PrefixCodeBlockTypesDistances(prefix_tree) => {
self.meta_block.prefix_tree_block_types_distances = Some(prefix_tree);

// debug(&format!("Prefix Code Block Types Distances = {:?}", self.meta_block.header.prefix_code_block_types_distances));
Expand All @@ -1993,8 +1945,7 @@ impl<R: Read> Decompressor<R> {
Err(e) => return Err(e),
};
},
State::PrefixCodeBlockCountsDistances((prefix_code, prefix_tree)) => {
self.meta_block.header.prefix_code_block_counts_distances = Some(prefix_code);
State::PrefixCodeBlockCountsDistances(prefix_tree) => {
self.meta_block.prefix_tree_block_counts_distances = Some(prefix_tree);

// debug(&format!("Prefix Code Block Counts Distances = {:?}", self.meta_block.header.prefix_code_block_counts_distances));
Expand Down Expand Up @@ -2101,10 +2052,7 @@ impl<R: Read> Decompressor<R> {
Err(e) => return Err(e),
};
},
State::PrefixCodesLiterals(prefix_codes_and_trees) => {
let (prefix_codes, prefix_trees): (Vec<_>, Vec<_>) = prefix_codes_and_trees.iter().cloned().unzip();

self.meta_block.header.prefix_codes_literals = Some(prefix_codes);
State::PrefixCodesLiterals(prefix_trees) => {
self.meta_block.prefix_trees_literals = Some(prefix_trees);

// debug(&format!("Prefix Codes Literals = {:?}", self.meta_block.header.prefix_codes_literals));
Expand All @@ -2115,10 +2063,7 @@ impl<R: Read> Decompressor<R> {
Err(e) => return Err(e),
};
},
State::PrefixCodesInsertAndCopyLengths(prefix_codes_and_trees) => {
let (prefix_codes, prefix_trees): (Vec<_>, Vec<_>) = prefix_codes_and_trees.iter().cloned().unzip();

self.meta_block.header.prefix_codes_insert_and_copy_lengths = Some(prefix_codes);
State::PrefixCodesInsertAndCopyLengths(prefix_trees) => {
self.meta_block.prefix_trees_insert_and_copy_lengths = Some(prefix_trees);

// println!("Prefix Codes Insert And Copy Lengths = {:?}", self.meta_block.header.prefix_codes_insert_and_copy_lengths);
Expand All @@ -2129,10 +2074,7 @@ impl<R: Read> Decompressor<R> {
Err(e) => return Err(e),
};
},
State::PrefixCodesDistances(prefix_codes_and_trees) => {
let (prefix_codes, prefix_trees): (Vec<_>, Vec<_>) = prefix_codes_and_trees.iter().cloned().unzip();

self.meta_block.header.prefix_codes_distances = Some(prefix_codes);
State::PrefixCodesDistances(prefix_trees) => {
self.meta_block.prefix_trees_distances = Some(prefix_trees);

// debug(&format!("Prefix Codes Distances = {:?}", self.meta_block.header.prefix_codes_distances));
Expand Down
2 changes: 1 addition & 1 deletion src/main.rs
View file
Original file line number Diff line number Diff line change
Expand Up @@ -6,4 +6,4 @@ use brotli::Decompressor;
fn main() {
let mut input = vec![];
let _ = Decompressor::new(&b"\x12\x1b\x00\x1e\x11\x00\x05\x09\x21\x00\x05\x04\x43\x05\xf5\x21\x1e\x11\x00\x05\xf5\x21\x00\x05\x04\x43".to_vec() as &[u8]).read_to_end(&mut input);
}
}

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