Gzip Swift Reference Documentation
CkoGzip
Current Version: 11.1.0
GZip compression component.
Object Creation
let obj = CkoGzip()!
Properties
AbortCurrent
When set to true, causes the currently running method to abort. Methods that always finish quickly (i.e.have no length file operations or network communications) are not affected. If no method is running, then this property is automatically reset to false when the next method is called. When the abort occurs, this property is reset to false. Both synchronous and asynchronous method calls can be aborted. (A synchronous method call could be aborted by setting this property from a separate thread.)
Comment
Specifies an optional comment string that can be embedded within the .gz when any Compress* method is called.
topCompressionLevel
The compression level to be used when compressing. The default is 6, which is the typical value used for zip utility programs when compressing data. The compression level may range from 0 (no compression) to 9 (the most compression). The benefits of trying to increase compression may not be worth the added expense in compression time. In many cases (which is data dependent), the improvement in compression is minimal while the increase in computation time is significant.
topDebugLogFilePath
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.
Filename
The filename that is embedded within the .gz during any Compress* method call. When extracting from a .gz using applications such as WinZip, this will be the filename that is created.
topHeartbeatMs
The interval in milliseconds between each AbortCheck event callback, which enables an application to abort certain method calls before they complete. By default, HeartbeatMs is set to 0, meaning no AbortCheck event callbacks will trigger.
LastErrorHtml
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
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
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
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.
LastModStr
The last-modification date/time to be embedded within the .gz when a Compress* method is called. By default, the current system date/time is used. Uses the RFC822 string format.
topUseCurrentDate
If set to true, the file produced by an Uncompress* method will use the current date/time for the last-modification date instead of the date/time found within the Gzip format.
VerboseLogging
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.
Version
Methods
CompressBd
In-place gzip the contents of binDat.
Returns true for success, false for failure.
CompressBdAsync (1)
Creates an asynchronous task to call the CompressBd method with the arguments provided.
Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.
Returns nil on failure
CompressFile
Compresses a file to create a GZip compressed file (.gz).
Returns true for success, false for failure.
CompressFileAsync (1)
Creates an asynchronous task to call the CompressFile method with the arguments provided.
Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.
Returns nil on failure
CompressFile2
Compresses a file to create a GZip compressed file (.gz). inFilename is the actual filename on disk. embeddedFilename is the filename to be embedded in the .gz such that when it is un-gzipped, this is the name of the file that will be created.
Returns true for success, false for failure.
CompressFile2Async (1)
Creates an asynchronous task to call the CompressFile2 method with the arguments provided.
Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.
Returns nil on failure
CompressFileBd
Gzip compresses a file into an in-memory .gz file stored in bd, with a maximum compressed size of 4GB.
Returns true for success, false for failure.
topCompressFileBdAsync (1)
Creates an asynchronous task to call the CompressFileBd method with the arguments provided.
Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.
Returns nil on failure
CompressFileToMem
Gzip compresses a file into an in-memory .gz image with a maximum size limit of 4GB.
Returns nil on failure
CompressFileToMemAsync (1)
Creates an asynchronous task to call the CompressFileToMem method with the arguments provided.
Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.
Returns nil on failure
CompressMemory
Compresses in-memory data to an in-memory image of a .gz file.
Note: There is a 4GB uncompressed size limitation. The uncompressed size of the file cannot be more than 4GB. Chilkat will be working to alleviate this limitation in the future.
Returns nil on failure
CompressMemoryAsync (1)
Creates an asynchronous task to call the CompressMemory method with the arguments provided.
Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.
Returns nil on failure
CompressMemToFile
Gzip compresses and creates a .gz file from in-memory data.
Returns true for success, false for failure.
topCompressMemToFileAsync (1)
Creates an asynchronous task to call the CompressMemToFile method with the arguments provided.
Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.
Returns nil on failure
CompressSb
Gzip compresses the byte representation of the string using the specified charset from charset (e.g., utf-8, iso-8859-1, or shift_JIS) and writes the compressed output to charset.
Returns true for success, false for failure.
topCompressSbAsync (1)
Creates an asynchronous task to call the CompressSb method with the arguments provided.
Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.
Returns nil on failure
CompressString
Gzip compresses a string and writes the output to a byte array. The string is first converted to the charset specified by destCharset. Typical charsets are utf-8, iso-8859-1, shift_JIS, etc.
Returns nil on failure
CompressStringAsync (1)
Creates an asynchronous task to call the CompressString method with the arguments provided.
Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.
Returns nil on failure
CompressStringENC
The same as CompressString, except the binary output is returned in encoded string form according to the encoding. The encoding can be any of the following: Base64, modBase64, Base32, UU, QP (for quoted-printable), URL (for url-encoding), Hex, Q, B, url_oath, url_rfc1738, url_rfc2396, and url_rfc3986.
Returns nil on failure
CompressStringToFile
Gzip compresses a string and writes the output to a .gz compressed file. The string is first converted to the charset specified by destCharset. Typical charsets are utf-8, iso-8859-1, shift_JIS, etc.
Returns true for success, false for failure.
CompressStringToFileAsync (1)
Creates an asynchronous task to call the CompressStringToFile method with the arguments provided.
Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.
Returns nil on failure
Decode
Decodes an encoded string and returns the original data. The encoding mode is determined by encoding. It may be base64, hex, quoted-printable, or url.
Returns nil on failure
DeflateStringENC
Provides the ability to use the zip/gzip's deflate algorithm directly to compress a string. Internal to this method, inString is first converted to the charset specified by charsetName. The data is then compressed using the deflate compression algorithm. The binary output is then encoded according to outputEncoding. Possible values for outputEncoding are hex, base64, url, and quoted-printable.
Note: The output of this method is compressed data with no Gzip file format. Use the Compress* methods to produce Gzip file format output.
Returns nil on failure
Encode
Encodes binary data to a printable string. The encoding mode is determined by encoding. It may be base64, hex, quoted-printable, or url.
Returns nil on failure
ExamineFile
Determines if the inGzFilename is a Gzip formatted file. Returns true if it is a Gzip formatted file, otherwise returns false.
ExamineMemory
Determines if the in-memory bytes (inGzData) contain a Gzip formatted file. Returns true if it is Gzip format, otherwise returns false.
InflateStringENC
This the reverse of DeflateStringENC.
The input string is first decoded according to inputEncoding. (Possible values for inputEncoding are hex, base64, url, and quoted-printable.) The compressed data is then inflated, and the result is then converted from convertFromCharset (if necessary) to return a string.
Returns nil on failure
IsGzip
Checks if the data in bd is in Gzip format. Returns true if it is, otherwise returns false.
LoadTaskCaller
ReadFile
Reads a binary file into memory and returns the byte array. Note: This method does not parse a Gzip, it is only a convenience method for reading a binary file into memory.
Returns nil on failure
SetDt
Sets the last-modification date/time to be embedded within the .gz when a Compress* method is called. If not explicitly set, the current system date/time is used.
Returns true for success, false for failure.
topSetExtraData
Sets the optional extra data that can be included within a .gz when a Compress* method is called. The extra binary data is passed in encoded form, where the encoding can be base64, hex, or ascii if simple text.
Returns true for success, false for failure.
topUncompressBd
UncompressBdAsync (1)
Creates an asynchronous task to call the UncompressBd method with the arguments provided.
Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.
Returns nil on failure
UncompressBdToFile
UncompressBdToFileAsync (1)
Creates an asynchronous task to call the UncompressBdToFile method with the arguments provided.
Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.
Returns nil on failure
UncompressFile
Un-Gzips a .gz file. The output filename is specified by the 2nd argument and not by the filename embedded within the .gz.
Returns true for success, false for failure.
UncompressFileAsync (1)
Creates an asynchronous task to call the UncompressFile method with the arguments provided.
Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.
Returns nil on failure
UncompressFileToMem
Un-Gzips a .gz file directly to memory.
Note: There is a 4GB uncompressed size limitation. The uncompressed size of the file cannot be more than 4GB. Chilkat will be working to alleviate this limitation in the future.
Returns nil on failure
UncompressFileToMemAsync (1)
Creates an asynchronous task to call the UncompressFileToMem method with the arguments provided.
Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.
Returns nil on failure
UncompressFileToString
Uncompresses a .gz file that contains a text file. The contents of the text file are returned as a string. The character encoding of the text file is specified by charset. Typical charsets are iso-8859-1, utf-8, windows-1252, shift_JIS, big5, etc.
Returns nil on failure
UncompressFileToStringAsync (1)
Creates an asynchronous task to call the UncompressFileToString method with the arguments provided.
Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.
Returns nil on failure
UncompressMemory
Un-Gzips from an in-memory image of a .gz file directly into memory.
Note: There is a 4GB uncompressed size limitation. The uncompressed size of the file cannot be more than 4GB. Chilkat will be working to alleviate this limitation in the future.
Returns nil on failure
UncompressMemoryAsync (1)
Creates an asynchronous task to call the UncompressMemory method with the arguments provided.
Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.
Returns nil on failure
UncompressMemToFile
Un-Gzips from an in-memory image of a .gz file to a file.
Returns true for success, false for failure.
topUncompressMemToFileAsync (1)
Creates an asynchronous task to call the UncompressMemToFile method with the arguments provided.
Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.
Returns nil on failure
UncompressString
The reverse of CompressString.
The bytes in inData are uncompressed, then converted from inCharset (if necessary) to return a string.
Returns nil on failure
UncompressStringAsync (1)
Creates an asynchronous task to call the UncompressString method with the arguments provided.
Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.
Returns nil on failure
UncompressStringENC
The same as UncompressString, except the compressed data is provided in encoded string form based on the value of encoding.
The encoding can be Base64, modBase64, Base32, UU, QP (for quoted-printable), URL (for url-encoding), Hex, Q, B, url_oath, url_rfc1738, url_rfc2396, and url_rfc3986.
Returns nil on failure
UnTarGz
Unpacks a .tar.gz file. The ungzip and untar occur in streaming mode. There are no temporary files and the memory footprint is constant (and small) while untarring. bNoAbsolute may be true or false. A value of true protects from untarring to absolute paths. (For example, imagine the trouble if the tar contains files with absolute paths beginning with /Windows/system32)
Returns true for success, false for failure.
topUnTarGzAsync (1)
Creates an asynchronous task to call the UnTarGz method with the arguments provided.
Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.
Returns nil on failure
WriteFile
A convenience method for writing a binary byte array to a file.
Returns true for success, false for failure.
topXfdlToXml
Converts base64-gzip .xfdl data to a decompressed XML string. The xfldData contains the base64 data. This method returns the decoded/decompressed XML string.
Returns nil on failure
Events
To implement an event callback, your application would define and implement a class that inherits from CkoBaseProgress. Your application can implement methods to override some or all of the default/empty method implementations of the CkoBaseProgress base class.
For example:
class MyGzipProgress : CkoBaseProgress {
override func ProgressInfo(name: String!, value: String!) {
// application code goes here...
print(name + ": " + value)
}
override func AbortCheck(abort: UnsafeMutablePointer) {
// application code goes here...
// To abort the operation, set this equal to true instead of false.
abort.memory = false
}
override func PercentDone(pctDone: NSNumber!, abort: UnsafeMutablePointer) {
// application code goes here...
print(pctDone)
// To abort the operation, set this equal to true instead of false.
abort.memory = false
}
// For asynchronous method calls.
override func TaskCompleted(task: CkoTask!) {
// application code goes here...
}
}
func someAppFunction() {
// Demonstrate how to set the event callback object...
let gzip = CkoGzip()
let myGzipProgress = MyGzipProgress()
gzip.setEventCallbackObject(myGzipProgress)
// ...
// ...
// ...
}
AbortCheck
Enables a method call to be aborted by triggering the AbortCheck event at intervals defined by the HeartbeatMs property. If HeartbeatMs is set to its default value of 0, no events will occur. For instance, set HeartbeatMs to 200 to trigger 5 AbortCheck events per second.
PercentDone
This provides the percentage completion for any method involving network communications or time-consuming processing, assuming the progress can be measured as a percentage. This event is triggered only when it's possible and logical to express the operation's progress as a percentage. The pctDone argument will range from 1 to 100. For methods that finish quickly, the number of PercentDone callbacks may vary, but the final callback will have pctDone equal to 100. For longer operations, callbacks will not exceed one per percentage point (e.g., 1, 2, 3, ..., 98, 99, 100).
The PercentDone callback also acts as an AbortCheck event. For fast methods where PercentDone fires, an AbortCheck event may not trigger since the PercentDone callback already provides an opportunity to abort. For longer operations, where time between PercentDone callbacks is extended, AbortCheck callbacks enable more responsive operation termination.
To abort the operation, set the abort output argument to true. This will cause the method to terminate and return a failure status or corresponding failure value.
ProgressInfo
This event callback provides tag name/value pairs that detail what occurs during a method call. To discover existing tag names, create code to handle the event, emit the pairs, and review them. Most tag names are self-explanatory.
TaskCompleted
Called from the background thread when an asynchronous task completes.
Deprecated
GetDt
Applications should instead access the LastModStr property.
Gets the last-modification date/time to be embedded within the .gz.
Returns nil on failure