Struct ipworkszip::Zstd

Properties   Methods   Events   Config Settings   Errors  

TBD.

Syntax

ipworkszip::Zstd

Remarks

TBD

Object Lifetime

The new() method returns a mutable reference to a struct instance. The object itself is kept in the global list maintained by IPWorksZip. Due to this, the Zstd struct cannot be disposed of automatically. Please, call the dispose(&mut self) method of Zstd when you have finished using the instance.

Property List

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The following is the full list of the properties of the struct with short descriptions. Click on the links for further details.

Method List

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The following is the full list of the methods of the struct with short descriptions. Click on the links for further details.

Event List

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The following is the full list of the events fired by the struct with short descriptions. Click on the links for further details.

Config Settings

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The following is a list of config settings for the struct with short descriptions. Click on the links for further details.

compression_level property (Zstd Struct)

The compression level to use.

Syntax

fn compression_level(&self ) -> Result<i32, IPWorksZipError> 
fn set_compression_level(&self, value : i32) ->  Option<IPWorksZipError> 

Default Value

4

Remarks

The compression level to use, from 1 to 6. Higher values will cause the component to compress better; lower values will cause the component to compress faster.

When get_compression_stream is invoked the stream will be created with the specified compression level. After a stream has been created it is independent of the control, and changing compression_level will have no effect on existing streams.

Data Type

i32

input_data property (Zstd Struct)

Specifies the data to compress or decompress.

Syntax

fn input_data(&self ) -> Result<Vec<u8>, IPWorksZipError> 
fn set_input_data(&self, value : Vec<u8>) ->  Option<IPWorksZipError> 
fn set_input_data_ref(&self, value : &[u8]) ->  Option<IPWorksZipError> 

Default Value

""

Remarks

This property specifies the data to compress or decompress.

When decompressing this should be set to the compressed data before calling decompress_data or decompress_block.

When compressing this should be set to the decompressed data before calling compress_data or compress_block.

When performing operations on multiple chunks of data, note that this property is not automatically cleared after each operation.

Data Type

Vec

output_data property (Zstd Struct)

The output data after compression or decompression.

Syntax

fn output_data(&self ) -> Result<Vec<u8>, IPWorksZipError> 

Default Value

""

Remarks

This property holds the compressed or decompressed data after compress_data or decompress_data is called.

This property is not applicable when calling compress_block or decompress_block.

This property is read-only.

Data Type

Vec

compress_block method (Zstd Struct)

Compresses a block of data.

Syntax

fn compress_block(&self, last_block : bool) -> Result<(), IPWorksZipError>

Remarks

This method compresses the block of data specified by input_data.

The compress_block and decompress_block methods operate on blocks (chunks) of data. The methods may be used to compress and decompress data as it becomes available.

Note that when using blocks of data the output_data property is not applicable. Instead data is made available through the on_compressed_data and on_decompressed_data events.

If all data is available ahead of time compress_data and decompress_data may be called instead.

Compress Data

Set input_data to the current block to be compressed. Next call compress_block to compress the current block. Note that compress_block takes a LastBlock parameter. If the block of data is the final block to be compressed set this to True. For all other blocks set this to False.

During compression the on_compressed_data event will fire with the compressed data. Note that this event may not fire for every call to compress_block due to the way the compression algorithm operates. For example:

zipstream.InputDataB = MyDecompressedData; zipstream.CompressBlock(); Data is accumulated inside the on_compressed_data event: private static void Zipstream_OnCompressedData(object sender, ZipstreamCompressedDataEventArgs e) { DoSomethingWith(e.DataB); }

Note that output_data is not applicable when compressing block data.

Decompress Data

Set input_data to the current block to be decompressed. Next call decompress_block to decompress the current block.

During decompression the on_decompressed_data event will fire with the decompressed data. Note that this event may not fire for every call to decompress_block due to the way the decompression algorithm operates. For example:

zipstream.InputDataB = MyCompressedData; zipstream.DecompressBlock(); Data is accumulated inside the on_decompressed_data event: private static void Zipstream_OnDecompressedData(object sender, ZipstreamDecompressedDataEventArgs e) { DoSomethingWith(e.DataB); }

Note that output_data is not applicable when decompressing block data.

compress_data method (Zstd Struct)

Compresses the specified data.

Syntax

fn compress_data(&self) -> Result<(), IPWorksZipError>

Remarks

This method compresses the data specified by input_data. After calling this method output_data holds the compressed data.

The compress_data and decompress_data methods operate on the complete blob of data. The entire compressed or decompressed data must be set to input_data before calling either method.

To compress and decompress data in blocks (chunks) see compress_block and decompress_block.

Compress Data

Set input_data to the decompressed data. This should be the entire data to be compressed. Next call compress_data. After compression output_data will hold the compressed data. For example:

zipstream.InputDataB = MyDecompressedData; zipstream.CompressData(); MyCompressedData = zipstream.OutputDataB;

In addition to output_data, the compressed data may also be accumulated within the on_compressed_data event.

Decompress Data

Set input_data to the compressed data. This should be the entire data to be decompressed. Next call decompress_data. After decompression output_data will hold the decompressed data. For example:

zipstream.InputDataB = MyCompressedData; zipstream.DecompressData(); MyDecompressedData = zipstream.OutputDataB;

In addition to output_data, the compressed data may also be accumulated within the on_decompressed_data event.

config method (Zstd Struct)

Sets or retrieves a configuration setting.

Syntax

fn config(&self, configuration_string : &str) ->  Result<String, IPWorksZipError>

Remarks

config is a generic method available in every struct. It is used to set and retrieve configuration settings for the struct.

These settings are similar in functionality to properties, but they are rarely used. In order to avoid "polluting" the property namespace of the struct, access to these internal properties is provided through the config method.

To set a configuration setting named PROPERTY, you must call Config("PROPERTY=VALUE"), where VALUE is the value of the setting expressed as a string. For boolean values, use the strings "True", "False", "0", "1", "Yes", or "No" (case does not matter).

To read (query) the value of a configuration setting, you must call Config("PROPERTY"). The value will be returned as a string.

decompress_block method (Zstd Struct)

Decompresses a block of data.

Syntax

fn decompress_block(&self) -> Result<(), IPWorksZipError>

Remarks

This method decompresses the block of data specified by input_data.

The compress_block and decompress_block methods operate on blocks (chunks) of data. The methods may be used to compress and decompress data as it becomes available.

Note that when using blocks of data the output_data property is not applicable. Instead data is made available through the on_compressed_data and on_decompressed_data events.

If all data is available ahead of time compress_data and decompress_data may be called instead.

Compress Data

Set input_data to the current block to be compressed. Next call compress_block to compress the current block. Note that compress_block takes a LastBlock parameter. If the block of data is the final block to be compressed set this to True. For all other blocks set this to False.

During compression the on_compressed_data event will fire with the compressed data. Note that this event may not fire for every call to compress_block due to the way the compression algorithm operates. For example:

zipstream.InputDataB = MyDecompressedData; zipstream.CompressBlock(); Data is accumulated inside the on_compressed_data event: private static void Zipstream_OnCompressedData(object sender, ZipstreamCompressedDataEventArgs e) { DoSomethingWith(e.DataB); }

Note that output_data is not applicable when compressing block data.

Decompress Data

Set input_data to the current block to be decompressed. Next call decompress_block to decompress the current block.

During decompression the on_decompressed_data event will fire with the decompressed data. Note that this event may not fire for every call to decompress_block due to the way the decompression algorithm operates. For example:

zipstream.InputDataB = MyCompressedData; zipstream.DecompressBlock(); Data is accumulated inside the on_decompressed_data event: private static void Zipstream_OnDecompressedData(object sender, ZipstreamDecompressedDataEventArgs e) { DoSomethingWith(e.DataB); }

Note that output_data is not applicable when decompressing block data.

decompress_data method (Zstd Struct)

Decompresses the specified data.

Syntax

fn decompress_data(&self) -> Result<(), IPWorksZipError>

Remarks

This method decompresses the data specified by input_data. After calling this method output_data holds the decompressed data.

The compress_data and decompress_data methods operate on the complete blob of data. The entire compressed or decompressed data must be set to input_data before calling either method.

To compress and decompress data in blocks (chunks) see compress_block and decompress_block.

Compress Data

Set input_data to the decompressed data. This should be the entire data to be compressed. Next call compress_data. After compression output_data will hold the compressed data. For example:

zipstream.InputDataB = MyDecompressedData; zipstream.CompressData(); MyCompressedData = zipstream.OutputDataB;

In addition to output_data, the compressed data may also be accumulated within the on_compressed_data event.

Decompress Data

Set input_data to the compressed data. This should be the entire data to be decompressed. Next call decompress_data. After decompression output_data will hold the decompressed data. For example:

zipstream.InputDataB = MyCompressedData; zipstream.DecompressData(); MyDecompressedData = zipstream.OutputDataB;

In addition to output_data, the compressed data may also be accumulated within the on_decompressed_data event.

reset method (Zstd Struct)

Resets the struct.

Syntax

fn reset(&self) -> Result<(), IPWorksZipError>

Remarks

reset resets the state of the struct. All properties will be set to their default values, and any files open will be closed.

on_compressed_data event (Zstd Struct)

This event fires with compressed data.

Syntax

// ZstdCompressedDataEventArgs carries the Zstd CompressedData event's parameters.
pub struct ZstdCompressedDataEventArgs {
  fn data(&self) -> &[u8]
}

// ZstdCompressedDataEvent defines the signature of the Zstd CompressedData event's handler function.
pub trait ZstdCompressedDataEvent {
  fn on_compressed_data(&self, sender : Zstd, e : &mut ZstdCompressedDataEventArgs);
}

impl <'a> Zstd<'a> {
  pub fn on_compressed_data(&self) -> &'a dyn ZstdCompressedDataEvent;
  pub fn set_on_compressed_data(&mut self, value : &'a dyn ZstdCompressedDataEvent);
  ...
}

Remarks

The on_compressed_data event fires as compressed data is available when compress_data or compress_block is called. This may fire one or more times when data is compressed.

data holds the current block of compressed data.

on_decompressed_data event (Zstd Struct)

This event fires with decompressed data.

Syntax

// ZstdDecompressedDataEventArgs carries the Zstd DecompressedData event's parameters.
pub struct ZstdDecompressedDataEventArgs {
  fn data(&self) -> &[u8]
}

// ZstdDecompressedDataEvent defines the signature of the Zstd DecompressedData event's handler function.
pub trait ZstdDecompressedDataEvent {
  fn on_decompressed_data(&self, sender : Zstd, e : &mut ZstdDecompressedDataEventArgs);
}

impl <'a> Zstd<'a> {
  pub fn on_decompressed_data(&self) -> &'a dyn ZstdDecompressedDataEvent;
  pub fn set_on_decompressed_data(&mut self, value : &'a dyn ZstdDecompressedDataEvent);
  ...
}

Remarks

The on_decompressed_data event fires as compressed data is available when decompress_data or decompress_block is called. This may fire one or more times as data is decompressed.

data holds the current block of decompressed data.

on_error event (Zstd Struct)

Information about errors during data delivery.

Syntax

// ZstdErrorEventArgs carries the Zstd Error event's parameters.
pub struct ZstdErrorEventArgs {
  fn error_code(&self) -> i32
  fn description(&self) -> &String
}

// ZstdErrorEvent defines the signature of the Zstd Error event's handler function.
pub trait ZstdErrorEvent {
  fn on_error(&self, sender : Zstd, e : &mut ZstdErrorEventArgs);
}

impl <'a> Zstd<'a> {
  pub fn on_error(&self) -> &'a dyn ZstdErrorEvent;
  pub fn set_on_error(&mut self, value : &'a dyn ZstdErrorEvent);
  ...
}

Remarks

The on_error event is fired in case of exceptional conditions during message processing. Normally the struct fails with an error.

error_code contains an error code and description contains a textual description of the error. For a list of valid error codes and their descriptions, please refer to the Error Codes section.

Config Settings (Zstd Struct)

The struct accepts one or more of the following configuration settings. Configuration settings are similar in functionality to properties, but they are rarely used. In order to avoid "polluting" the property namespace of the struct, access to these internal properties is provided through the config method.

No configuration settings defined.

Base Config Settings

Trappable Errors (Zstd Struct)

Note that the streams returned by get_compression_stream and get_decompression_stream will throw standard IOExceptions in case of error.

ZipStream Errors