Compression Unicode C Reference Documentation
Compression
Current Version: 10.1.2
Implements the Bzip2, Deflate, and LZW compression algorithms.
Create/Dispose
HCkCompressionW instance = CkCompressionW_Create(); // ... CkCompressionW_Dispose(instance);
Creates an instance of the HCkCompressionW object and returns a handle ("void *" pointer). The handle is passed in the 1st argument for the functions listed on this page.
Objects created by calling CkCompressionW_Create must be freed by calling this method. A memory leak occurs if a handle is not disposed by calling this function. Also, any handle returned by a Chilkat "C" function must also be freed by the application by calling the appropriate Dispose method, such as CkCompressionW_Dispose.
Callback Functions
Provides the opportunity for a method call to be aborted. If TRUE is returned, the operation in progress is aborted. Return FALSE to allow the current method call to continue. This callback function is called periodically based on the value of the HeartbeatMs property. (If HeartbeatMs is 0, then no callbacks are made.) As an example, to make 5 AbortCheck callbacks per second, set the HeartbeatMs property equal to 200.
Provides the percentage completed for any method that involves network communications or time-consuming processing (assuming it is a method where a percentage completion can be measured). This callback is only called when it is possible to know a percentage completion, and when it makes sense to express the operation as a percentage completed. The pctDone argument will have a value from 1 to 100. For methods that complete very quickly, the number of PercentDone callbacks will vary, but the final callback should have a value of 100. For long running operations, no more than one callback per percentage point will occur (for example: 1, 2, 3, ... 98, 99, 100).
This callback counts as an AbortCheck callback, and takes the place of the AbortCheck event when it fires.
The return value indicates whether the method call should be aborted, or whether it should proceed. Return TRUE to abort, and FALSE to proceed.
This is a general callback that provides name/value information about what is happening at certain points during a method call. To see the information provided in ProgressInfo callbacks, if any, write code to handle this event and log the name/value pairs. Most are self-explanatory.
Called in the background thread when an asynchronous task completes. (Note: When an async method is running, all callbacks are in the background thread.)
Properties
Algorithm
void CkCompressionW_putAlgorithm(HCkCompressionW cHandle, const wchar_t *newVal);
const wchar_t *CkCompressionW_algorithm(HCkCompressionW cHandle);
Specifies the compression algorithm: "deflate", "zlib", "bzip2", or "lzw". Note that "ppmd" is deprecated and should not be used. It was only available for 32-bit systems and specifically used the "J" variant. Please transition to one of the recommended algorithms.
topCharset
void CkCompressionW_putCharset(HCkCompressionW cHandle, const wchar_t *newVal);
const wchar_t *CkCompressionW_charset(HCkCompressionW cHandle);
Only applies to methods that compress or decompress strings. This specifies the character encoding that the string should be converted to before compression. Many programming languages use Unicode (2 bytes per char) for representing characters. This property allows for the string to be converted to a 1-byte per char encoding prior to compression.
topDebugLogFilePath
void CkCompressionW_putDebugLogFilePath(HCkCompressionW cHandle, const wchar_t *newVal);
const wchar_t *CkCompressionW_debugLogFilePath(HCkCompressionW cHandle);
If set to a file path, this property logs the LastErrorText of each Chilkat method or property call to the specified file. This logging helps identify the context and history of Chilkat calls leading up to any crash or hang, aiding in debugging.
Enabling the VerboseLogging property provides more detailed information. This property is mainly used for debugging rare instances where a Chilkat method call causes a hang or crash, which should generally not happen.
Possible causes of hangs include:
- A timeout property set to 0, indicating an infinite timeout.
- A hang occurring within an event callback in the application code.
- An internal bug in the Chilkat code causing the hang.
DeflateLevel
void CkCompressionW_putDeflateLevel(HCkCompressionW cHandle, int newVal);
This property allows for customization of the compression level for the "deflate" and "zlib" compression algoirthms. ("zlib" is just the deflate algorithm with a zlib header.) A value of 0 = no compression, while 9 = maximum compression. The default is 6.
topEncodingMode
void CkCompressionW_putEncodingMode(HCkCompressionW cHandle, const wchar_t *newVal);
const wchar_t *CkCompressionW_encodingMode(HCkCompressionW cHandle);
Controls the encoding expected by methods ending in "ENC", such as CompressBytesENC. Valid values are "base64", "hex", "url", and "quoted-printable". Compression methods ending in ENC return the binary compressed data as an encoded string using this encoding. Decompress methods expect the input string to be this encoding.
topHeartbeatMs
void CkCompressionW_putHeartbeatMs(HCkCompressionW cHandle, int newVal);
The number of milliseconds between each AbortCheck event callback. The AbortCheck callback allows an application to abort any method call prior to completion. If HeartbeatMs is 0 (the default), no AbortCheck event callbacks will fire.
topLastErrorHtml
const wchar_t *CkCompressionW_lastErrorHtml(HCkCompressionW cHandle);
Provides HTML-formatted information about the last called method or property. If a method call fails or behaves unexpectedly, check this property for details. Note that information is available regardless of the method call's success.
topLastErrorText
const wchar_t *CkCompressionW_lastErrorText(HCkCompressionW cHandle);
Provides plain text information about the last called method or property. If a method call fails or behaves unexpectedly, check this property for details. Note that information is available regardless of the method call's success.
LastErrorXml
const wchar_t *CkCompressionW_lastErrorXml(HCkCompressionW cHandle);
Provides XML-formatted information about the last called method or property. If a method call fails or behaves unexpectedly, check this property for details. Note that information is available regardless of the method call's success.
topLastMethodSuccess
void CkCompressionW_putLastMethodSuccess(HCkCompressionW cHandle, BOOL newVal);
Indicates the success or failure of the most recent method call: TRUE means success, FALSE means failure. This property remains unchanged by property setters or getters. This method is present to address challenges in checking for null or Nothing returns in certain programming languages.
topVerboseLogging
void CkCompressionW_putVerboseLogging(HCkCompressionW cHandle, BOOL newVal);
If set to TRUE, then the contents of LastErrorText (or LastErrorXml, or LastErrorHtml) may contain more verbose information. The default value is FALSE. Verbose logging should only be used for debugging. The potentially large quantity of logged information may adversely affect peformance.
topVersion
const wchar_t *CkCompressionW_version(HCkCompressionW cHandle);
Methods
BeginCompressBytes
Large amounts of binary byte data may be compressed in chunks by first calling BeginCompressBytes, followed by 0 or more calls to MoreCompressedBytes, and ending with a final call to EndCompressBytes. Each call returns 0 or more bytes of compressed data which may be output to a compressed data stream (such as a file, socket, etc.).
Returns TRUE for success, FALSE for failure.
topBeginCompressBytesAsync (1)
Creates an asynchronous task to call the BeginCompressBytes method with the arguments provided.
Returns NULL on failure
topBeginCompressBytes2
Large amounts of binary byte data may be compressed in chunks by first calling BeginCompressBytes, followed by 0 or more calls to MoreCompressedBytes, and ending with a final call to EndCompressBytes. Each call returns 0 or more bytes of compressed data which may be output to a compressed data stream (such as a file, socket, etc.).
Returns TRUE for success, FALSE for failure.
topBeginCompressBytesENC
const wchar_t *CkCompressionW_beginCompressBytesENC(HCkCompressionW cHandle, HCkByteData data);
Large amounts of binary byte data may be compressed in chunks by first calling BeginCompressBytesENC, followed by 0 or more calls to MoreCompressedBytesENC, and ending with a final call to EndCompressBytesENC. Each call returns 0 or more characters of compressed data (encoded as a string according to the EncodingMode property setting) which may be output to a compressed data stream (such as a file, socket, etc.).
Returns TRUE for success, FALSE for failure.
topBeginCompressBytesENCAsync (1)
Creates an asynchronous task to call the BeginCompressBytesENC method with the arguments provided.
Returns NULL on failure
topBeginCompressString
Large amounts of string data may be compressed in chunks by first calling BeginCompressString, followed by 0 or more calls to MoreCompressedString, and ending with a final call to EndCompressString. Each call returns 0 or more bytes of compressed data which may be output to a compressed data stream (such as a file, socket, etc.).
Returns TRUE for success, FALSE for failure.
topBeginCompressStringAsync (1)
Creates an asynchronous task to call the BeginCompressString method with the arguments provided.
Returns NULL on failure
topBeginCompressStringENC
const wchar_t *CkCompressionW_beginCompressStringENC(HCkCompressionW cHandle, const wchar_t *str);
Large amounts of string data may be compressed in chunks by first calling BeginCompressStringENC, followed by 0 or more calls to MoreCompressedStringENC, and ending with a final call to EndCompressStringENC. Each call returns 0 or more characters of compressed data (encoded as a string according to the EncodingMode property setting) which may be output to a compressed data stream (such as a file, socket, etc.).
Returns TRUE for success, FALSE for failure.
BeginCompressStringENCAsync (1)
Creates an asynchronous task to call the BeginCompressStringENC method with the arguments provided.
Returns NULL on failure
topBeginDecompressBytes
A compressed data stream may be decompressed in chunks by first calling BeginDecompressBytes, followed by 0 or more calls to MoreDecompressedBytes, and ending with a final call to EndDecompressBytes. Each call returns 0 or more bytes of decompressed data.
Returns TRUE for success, FALSE for failure.
topBeginDecompressBytesAsync (1)
Creates an asynchronous task to call the BeginDecompressBytes method with the arguments provided.
Returns NULL on failure
topBeginDecompressBytes2
A compressed data stream may be decompressed in chunks by first calling BeginDecompressBytes, followed by 0 or more calls to MoreDecompressedBytes, and ending with a final call to EndDecompressBytes. Each call returns 0 or more bytes of decompressed data.
Returns TRUE for success, FALSE for failure.
topBeginDecompressBytesENC
The input to this method is an encoded string containing compressed data. The EncodingMode property should be set prior to calling this method. The input string is decoded according to the EncodingMode (hex, base64, etc.) and then decompressed.
A compressed data stream may be decompressed in chunks by first calling BeginDecompressBytesENC, followed by 0 or more calls to MoreDecompressedBytesENC, and ending with a final call to EndDecompressBytesENC. Each call returns 0 or more bytes of decompressed data.
Returns TRUE for success, FALSE for failure.
topBeginDecompressBytesENCAsync (1)
Creates an asynchronous task to call the BeginDecompressBytesENC method with the arguments provided.
Returns NULL on failure
topBeginDecompressString
const wchar_t *CkCompressionW_beginDecompressString(HCkCompressionW cHandle, HCkByteData data);
A compressed data stream may be decompressed in chunks by first calling BeginDecompressString, followed by 0 or more calls to MoreDecompressedString, and ending with a final call to EndDecompressString. Each call returns 0 or more characters of decompressed text.
Returns TRUE for success, FALSE for failure.
topBeginDecompressStringAsync (1)
Creates an asynchronous task to call the BeginDecompressString method with the arguments provided.
Returns NULL on failure
topBeginDecompressStringENC
const wchar_t *CkCompressionW_beginDecompressStringENC(HCkCompressionW cHandle, const wchar_t *str);
The input to this method is an encoded string containing compressed data. The EncodingMode property should be set prior to calling this method. The input string is decoded according to the EncodingMode (hex, base64, etc.) and then decompressed.
A compressed data stream may be decompressed in chunks by first calling BeginDecompressStringENC, followed by 0 or more calls to MoreDecompressedStringENC, and ending with a final call to EndDecompressStringENC. Each call returns 0 or more characters of decompressed text.
Returns TRUE for success, FALSE for failure.
topBeginDecompressStringENCAsync (1)
Creates an asynchronous task to call the BeginDecompressStringENC method with the arguments provided.
Returns NULL on failure
topCompressBd
Compresses the data contained in a BinData object.
Returns TRUE for success, FALSE for failure.
CompressBdAsync (1)
Creates an asynchronous task to call the CompressBd method with the arguments provided.
Returns NULL on failure
topCompressBytes
CompressBytesAsync (1)
Creates an asynchronous task to call the CompressBytes method with the arguments provided.
Returns NULL on failure
topCompressBytes2
CompressBytesENC
const wchar_t *CkCompressionW_compressBytesENC(HCkCompressionW cHandle, HCkByteData data);
Compresses bytes and returns the compressed data encoded to a string. The encoding (hex, base64, etc.) is determined by the EncodingMode property setting.
Returns TRUE for success, FALSE for failure.
topCompressBytesENCAsync (1)
Creates an asynchronous task to call the CompressBytesENC method with the arguments provided.
Returns NULL on failure
topCompressEncryptFile
Performs file-to-file compression and encryption. Files of any size may be compressed because the file is compressed and encrypted internally in streaming mode.
Returns TRUE for success, FALSE for failure.
CompressEncryptFileAsync (1)
Creates an asynchronous task to call the CompressEncryptFile method with the arguments provided.
Returns NULL on failure
topCompressFile
Performs file-to-file compression. Files of any size may be compressed because the file is compressed internally in streaming mode.
Returns TRUE for success, FALSE for failure.
CompressFileAsync (1)
Creates an asynchronous task to call the CompressFile method with the arguments provided.
Returns NULL on failure
topCompressSb
Compresses the contents of sb and appends the compressed bytes to binData.
Returns TRUE for success, FALSE for failure.
topCompressSbAsync (1)
Creates an asynchronous task to call the CompressSb method with the arguments provided.
Returns NULL on failure
topCompressStream
Compresses a stream. Internally, the strm's source is read, compressed, and the compressed data written to the strm's sink. It does this in streaming fashion. Extremely large or even infinite streams can be compressed with stable ungrowing memory usage.
Returns TRUE for success, FALSE for failure.
CompressStreamAsync (1)
Creates an asynchronous task to call the CompressStream method with the arguments provided.
Returns NULL on failure
topCompressString
CompressStringAsync (1)
Creates an asynchronous task to call the CompressString method with the arguments provided.
Returns NULL on failure
topCompressStringENC
const wchar_t *CkCompressionW_compressStringENC(HCkCompressionW cHandle, const wchar_t *str);
Compresses a string and returns the compressed data encoded to a string. The output encoding (hex, base64, etc.) is determined by the EncodingMode property setting.
Returns TRUE for success, FALSE for failure.
CompressStringENCAsync (1)
Creates an asynchronous task to call the CompressStringENC method with the arguments provided.
Returns NULL on failure
topDecompressBd
Decompresses the data contained in a BinData object.
Returns TRUE for success, FALSE for failure.
DecompressBdAsync (1)
Creates an asynchronous task to call the DecompressBd method with the arguments provided.
Returns NULL on failure
topDecompressBytes
DecompressBytesAsync (1)
Creates an asynchronous task to call the DecompressBytes method with the arguments provided.
Returns NULL on failure
topDecompressBytes2
DecompressBytesENC
The opposite of CompressBytesENC. encodedCompressedData contains the compressed data as an encoded string (hex, base64, etc) as specified by the EncodingMode property setting.
Returns TRUE for success, FALSE for failure.
topDecompressBytesENCAsync (1)
Creates an asynchronous task to call the DecompressBytesENC method with the arguments provided.
Returns NULL on failure
topDecompressFile
Performs file-to-file decompression (the opposite of CompressFile). Internally the file is decompressed in streaming mode which allows files of any size to be decompressed.
Returns TRUE for success, FALSE for failure.
DecompressFileAsync (1)
Creates an asynchronous task to call the DecompressFile method with the arguments provided.
Returns NULL on failure
topDecompressSb
Decompresses the contents of binData and appends the decompressed string to sb.
Returns TRUE for success, FALSE for failure.
topDecompressSbAsync (1)
Creates an asynchronous task to call the DecompressSb method with the arguments provided.
Returns NULL on failure
topDecompressStream
Decompresses a stream. Internally, the strm's source is read, decompressed, and the decompressed data written to the strm's sink. It does this in streaming fashion. Extremely large or even infinite streams can be decompressed with stable ungrowing memory usage.
Returns TRUE for success, FALSE for failure.
DecompressStreamAsync (1)
Creates an asynchronous task to call the DecompressStream method with the arguments provided.
Returns NULL on failure
topDecompressString
const wchar_t *CkCompressionW_decompressString(HCkCompressionW cHandle, HCkByteData data);
Takes compressed bytes, decompresses, and returns the resulting string.
Returns TRUE for success, FALSE for failure.
topDecompressStringAsync (1)
Creates an asynchronous task to call the DecompressString method with the arguments provided.
Returns NULL on failure
topDecompressStringENC
const wchar_t *CkCompressionW_decompressStringENC(HCkCompressionW cHandle, const wchar_t *encodedCompressedData);
The opposite of CompressStringENC. encodedCompressedData contains the compressed data as an encoded string (hex, base64, etc) as specified by the EncodingMode property setting.
Returns TRUE for success, FALSE for failure.
DecompressStringENCAsync (1)
Creates an asynchronous task to call the DecompressStringENC method with the arguments provided.
Returns NULL on failure
topDecryptDecompressFile
Performs file-to-file decryption and decompression.
Returns TRUE for success, FALSE for failure.
DecryptDecompressFileAsync (1)
Creates an asynchronous task to call the DecryptDecompressFile method with the arguments provided.
Returns NULL on failure
topEndCompressBytes
Must be callled to finalize a compression stream. Returns any remaining (buffered) compressed data.
(See BeginCompressBytes)
Returns TRUE for success, FALSE for failure.
topEndCompressBytesAsync (1)
Creates an asynchronous task to call the EndCompressBytes method with the arguments provided.
Returns NULL on failure
topEndCompressBytesENC
const wchar_t *CkCompressionW_endCompressBytesENC(HCkCompressionW cHandle);
Must be callled to finalize a compression stream. Returns any remaining (buffered) compressed data.
(See BeginCompressBytesENC)
Returns TRUE for success, FALSE for failure.
topEndCompressBytesENCAsync (1)
Creates an asynchronous task to call the EndCompressBytesENC method with the arguments provided.
Returns NULL on failure
topEndCompressString
Must be callled to finalize a compression stream. Returns any remaining (buffered) compressed data.
(See BeginCompressString)
Returns TRUE for success, FALSE for failure.
topEndCompressStringAsync (1)
Creates an asynchronous task to call the EndCompressString method with the arguments provided.
Returns NULL on failure
topEndCompressStringENC
const wchar_t *CkCompressionW_endCompressStringENC(HCkCompressionW cHandle);
Must be callled to finalize a compression stream. Returns any remaining (buffered) compressed data.
(See BeginCompressStringENC)
Returns TRUE for success, FALSE for failure.
EndCompressStringENCAsync (1)
Creates an asynchronous task to call the EndCompressStringENC method with the arguments provided.
Returns NULL on failure
topEndDecompressBytes
Called to finalize the decompression stream and return any remaining (buffered) decompressed data.
(See BeginDecompressBytes)
Returns TRUE for success, FALSE for failure.
topEndDecompressBytesAsync (1)
Creates an asynchronous task to call the EndDecompressBytes method with the arguments provided.
Returns NULL on failure
topEndDecompressBytesENC
Called to finalize the decompression stream and return any remaining (buffered) decompressed data.
The input to this method is an encoded string containing compressed data. The EncodingMode property should be set prior to calling this method. The input string is decoded according to the EncodingMode (hex, base64, etc.) and then decompressed.
(See BeginDecompressBytesENC)
Returns TRUE for success, FALSE for failure.
topEndDecompressBytesENCAsync (1)
Creates an asynchronous task to call the EndDecompressBytesENC method with the arguments provided.
Returns NULL on failure
topEndDecompressString
const wchar_t *CkCompressionW_endDecompressString(HCkCompressionW cHandle);
Called to finalize the decompression stream and return any remaining (buffered) decompressed data.
(See BeginDecompressString)
Returns TRUE for success, FALSE for failure.
EndDecompressStringAsync (1)
Creates an asynchronous task to call the EndDecompressString method with the arguments provided.
Returns NULL on failure
topEndDecompressStringENC
const wchar_t *CkCompressionW_endDecompressStringENC(HCkCompressionW cHandle);
Called to finalize the decompression stream and return any remaining (buffered) decompressed data.
The input to this method is an encoded string containing compressed data. The EncodingMode property should be set prior to calling this method. The input string is decoded according to the EncodingMode (hex, base64, etc.) and then decompressed.
(See BeginDecompressStringENC)
Returns TRUE for success, FALSE for failure.
topEndDecompressStringENCAsync (1)
Creates an asynchronous task to call the EndDecompressStringENC method with the arguments provided.
Returns NULL on failure
topLoadTaskCaller
MoreCompressBytes
MoreCompressBytesAsync (1)
Creates an asynchronous task to call the MoreCompressBytes method with the arguments provided.
Returns NULL on failure
topMoreCompressBytes2
MoreCompressBytesENC
const wchar_t *CkCompressionW_moreCompressBytesENC(HCkCompressionW cHandle, HCkByteData data);
MoreCompressBytesENCAsync (1)
Creates an asynchronous task to call the MoreCompressBytesENC method with the arguments provided.
Returns NULL on failure
topMoreCompressString
MoreCompressStringAsync (1)
Creates an asynchronous task to call the MoreCompressString method with the arguments provided.
Returns NULL on failure
topMoreCompressStringENC
const wchar_t *CkCompressionW_moreCompressStringENC(HCkCompressionW cHandle, const wchar_t *str);
(See BeginCompressStringENC)
Returns TRUE for success, FALSE for failure.
MoreCompressStringENCAsync (1)
Creates an asynchronous task to call the MoreCompressStringENC method with the arguments provided.
Returns NULL on failure
topMoreDecompressBytes
MoreDecompressBytesAsync (1)
Creates an asynchronous task to call the MoreDecompressBytes method with the arguments provided.
Returns NULL on failure
topMoreDecompressBytes2
MoreDecompressBytesENC
The input to this method is an encoded string containing compressed data. The EncodingMode property should be set prior to calling this method. The input string is decoded according to the EncodingMode (hex, base64, etc.) and then decompressed.
(See BeginDecompressBytesENC)
Returns TRUE for success, FALSE for failure.
topMoreDecompressBytesENCAsync (1)
Creates an asynchronous task to call the MoreDecompressBytesENC method with the arguments provided.
Returns NULL on failure
topMoreDecompressString
const wchar_t *CkCompressionW_moreDecompressString(HCkCompressionW cHandle, HCkByteData data);
MoreDecompressStringAsync (1)
Creates an asynchronous task to call the MoreDecompressString method with the arguments provided.
Returns NULL on failure
topMoreDecompressStringENC
const wchar_t *CkCompressionW_moreDecompressStringENC(HCkCompressionW cHandle, const wchar_t *str);
The input to this method is an encoded string containing compressed data. The EncodingMode property should be set prior to calling this method. The input string is decoded according to the EncodingMode (hex, base64, etc.) and then decompressed.
(See BeginDecompressStringENC)
Returns TRUE for success, FALSE for failure.
topMoreDecompressStringENCAsync (1)
Creates an asynchronous task to call the MoreDecompressStringENC method with the arguments provided.
Returns NULL on failure
top