class ChunkedDecompressor
Defined at line 45 of file ../../src/lib/chunked-compression/chunked-decompressor.h
ChunkedDecompressor allows chunked archives to be decompressed (either a frame at a time, or in
full).
Usage (error checks omitted):
// Load the header into memory.
const void* header = InputDataHeader();
size_t header_length = 8192; // Read-ahead size for the file header
size_t compressed_length = InputLength(); // Assume >8192
HeaderReader reader;
SeekTable table = reader.Parse(header, header_length, compressed_length);
ChunkedDecompressor decompressor;
size_t target_offset = TargetOffset();
unsigned table_index = table.EntryForDecompressedOffset(TargetOffset()).get();
const SeekTableEntry
&
entry = table.Entries()[table_index];
fbl::Array
<uint8
_t> output_buffer(new uint8_t[entry.decompressed_size],
entry.decompressed_size);
size_t input_chunk_size = entry.compressed_size;
const uint8_t *input_chunk = LoadCompressedData(entry.compressed_offset, input_chunk_size);
size_t bytes_written;
decompressor.DecompressFrame(table, table_index, input_chunk, input_chunk_size,
output_buffer.get(), output_buffer.size(),
&bytes
_written);
Public Methods
void ChunkedDecompressor ()Defined at line 34 of file ../../src/lib/chunked-compression/chunked-decompressor.cc
void ~ChunkedDecompressor ()Defined at line 36 of file ../../src/lib/chunked-compression/chunked-decompressor.cc
Status DecompressBytes (const void * input, size_t len, fbl::Array<uint8_t> * output, size_t * bytes_written_out)Convenience method to do a one-shot decompression of |input|, returning an allocated buffer
containing the decompressed bytes.
Defined at line 38 of file ../../src/lib/chunked-compression/chunked-decompressor.cc
void ChunkedDecompressor (ChunkedDecompressor && o)Defined at line 49 of file ../../src/lib/chunked-compression/chunked-decompressor.h
ChunkedDecompressor & operator= (ChunkedDecompressor && o)Defined at line 50 of file ../../src/lib/chunked-compression/chunked-decompressor.h
void ChunkedDecompressor (const ChunkedDecompressor & )Defined at line 51 of file ../../src/lib/chunked-compression/chunked-decompressor.h
ChunkedDecompressor & operator= (const ChunkedDecompressor & )Defined at line 51 of file ../../src/lib/chunked-compression/chunked-decompressor.h
Status Decompress (const SeekTable & table, const void * input, size_t len, void * output, size_t output_len, size_t * bytes_written_out)Reads the decompressed archive described by |table| from |input|, and writes the decompressed
data to |output|.
|input| should include the full archive contents, including the table itself. The table is
not validated (having already been validated during construction of |table|).
|output_len| must be at least |ComputeOutputSize(table)| bytes long.
Returns the number of decompressed bytes written in |bytes_written_out|.
Defined at line 58 of file ../../src/lib/chunked-compression/chunked-decompressor.cc
size_t ComputeOutputSize (const SeekTable & table)Returns the minimum size that a buffer must be to hold the result of decompressing the archive
described by |table|.
Defined at line 60 of file ../../src/lib/chunked-compression/chunked-decompressor.h
Status DecompressFrame (const void * input_frame, size_t input_frame_len, void * output, size_t output_len, size_t * bytes_written_out)|input_frame| should start at the frame's first byte, and |input_frame_len| must be big enough
to span the entire frame.
|output| starts at the first byte to write the result, and |output_len| must be the resulting
decompressed size.
Returns the number of decompressed bytes written in |bytes_written_out|.
Defined at line 88 of file ../../src/lib/chunked-compression/chunked-decompressor.cc
Status DecompressFrame (const SeekTable & table, unsigned int table_index, const void * input_frame, size_t input_frame_len, void * output, size_t output_len, size_t * bytes_written_out)Reads the |table_index|'th frame of the decompressed archive described by |table| from
|input_frame|, and writes the decompressed frame to |output|.
|input_frame| should start at the frame's first byte, and |input_frame_len| must be big enough
to span the entire frame.
|output_len| must be at least as big as |table.Entries()[table_index].decompressed_size|.
Returns the number of decompressed bytes written in |bytes_written_out|.
Defined at line 112 of file ../../src/lib/chunked-compression/chunked-decompressor.cc