Compressing -and Decompressing File

diff -r 4816d766a08a -r f345bda72bc4 Symbian3/PDK/Source/GUID-84922B27-FDCF-56FD-91ED-5E0BFE3ED0E4.dita --- a/Symbian3/PDK/Source/GUID-84922B27-FDCF-56FD-91ED-5E0BFE3ED0E4.dita Tue Mar 30 11:42:04 2010 +0100 +++ b/Symbian3/PDK/Source/GUID-84922B27-FDCF-56FD-91ED-5E0BFE3ED0E4.dita Tue Mar 30 11:56:28 2010 +0100 @@ -1,147 +1,147 @@ - - - - - -Compressing -and Decompressing File - Zip Format The Zip Compression Library, EZLib provides stream and file compression -and decompression functionality for the Symbian platforms. The files can be -compressed to two formats namely zip and gzip. Compression and Decompression -are performed iteratively, till the completion of required task. - - -Pass the input and -output files as parameters to construct an instance of CEZFileBufferManager. -This returns a pointer to CEZFileBufferManager (input buffer). - CEZFileBufferManager provides functions that accept -and converts the data into buffers for MEZBufferManager class -to manage it internally. - - -Pass the input buffer and other compression parameters to the object -of the CEZCompressor class. - - -Use CEZCompressor::DeflateL() to compress the file. - - -

The following code demonstrates a compression procedure.

/* - * Compresses the file into a zip file using the EZlib component. - * It is assumed that the input and output file names are contained in a - * provided ini file. - */ - - -void CEZlibEZipTests::DoEZlibDeflateL() - { -RFs iFs; - iFS.connect(); - - - - //Open input file -_LIT(KInputFileLocation, "c:\\private\\E80000B7\\zip\\input\\input.doc"); -TFileName inputFile(KInputFileLocation); - RFile input; - err = input.Open(iFs, inputFile, EFileStream | EFileRead | EFileShareExclusive); - if(err != KErrNone) - { - INFO_PRINTF1(KOpenFileError); - User::Leave(err); - } - - - - //open output file - -_LIT(KOutputFileLocation, "c:\\private\\E80000B7\\zip\\input\\output.zip"); -TFileName outputFile(KOutputFileLocation); - RFile output; - err = output.Replace(iFs, outputFile, EFileStream | EFileWrite | EFileShareExclusive); - if(err != KErrNone) - { - INFO_PRINTF1(KCreateFileError); - User::Leave(err); - } - - - - CEZFileBufferManager *bufferManager = CEZFileBufferManager::NewLC(input, output); - CEZCompressor *compressor = CEZCompressor::NewLC(*bufferManager, aLevel, aWindowBits, aMemLevel, aStrategy); - - while(compressor->DeflateL()) - { - } - output.Close(); -input.Close(); - iFS.Close(); - - - - } - -

The decompression of a .zip file can be achieved -through the following the steps:

Pass the -input and output files as parameters to construct an instance of CEZFileBufferManager. -This returns a pointer to CEZFileBufferManager ( buffer).
Pass the buffer to the -object of the CEZDecompressor class.
CEZDecompressor::InflateL() is -called repeatedly until the decompression is complete.

The following code demonstrates the decompression procedure.

/* Decompresses the file contained in a Zip file using the EZlib component. - * It is assumed that the input and output file names are contained in a - * provided ini file. - */ - -void CEZlibEZipTests::DoEZlibInflateL() - { -RFs iFs; - iFS.connect(); - -//Open input file -_LIT(KInputFileLocation, "c:\\private\\E80000B7\\zip\\input\\output.zip"); -TFileName inputFile(KInputFileLocation); - RFile input; - err = input.Open(iRfs, inputFile, EFileStream | EFileRead | EFileShareExclusive); - if(err != KErrNone) - { - INFO_PRINTF1(KOpenFileError); - User::Leave(err); - } - - - - //open output file - -_LIT(KOutputFile, "c:\\private\\E80000B7\\zip\\input\\input.doc"); -TFileName outputFile(KOutputFile); - RFile output; - err = output.Replace(iFs, outputFile, EFileStream | EFileWrite | EFileShareExclusive); - if(err != KErrNone) - { - INFO_PRINTF1(KCreateFileError); - User::Leave(err); - } - - - -CEZFileBufferManager *bufferManager = CEZFileBufferManager::NewLC(input, Output); -CEZDecompressor *decompressor = CEZDecompressor::NewLC(*bufferManager, aWindowBits); - - - while(decompressor->InflateL()) - { - } -output.Close(); - input.Close(); - ifs.Close(); - - } + + + + + +Compressing +and Decompressing File - Zip Format The Zip Compression Library, EZLib provides stream and file compression +and decompression functionality for the Symbian platforms. The files can be +compressed to two formats namely zip and gzip. Compression and Decompression +are performed iteratively, till the completion of required task. + + +Pass the input and +output files as parameters to construct an instance of CEZFileBufferManager. +This returns a pointer to CEZFileBufferManager (input buffer). + CEZFileBufferManager provides functions that accept +and converts the data into buffers for MEZBufferManager class +to manage it internally. + + +Pass the input buffer and other compression parameters to the object +of the CEZCompressor class. + + +Use CEZCompressor::DeflateL() to compress the file. + + +

The following code demonstrates a compression procedure.

/* + * Compresses the file into a zip file using the EZlib component. + * It is assumed that the input and output file names are contained in a + * provided ini file. + */ + + +void CEZlibEZipTests::DoEZlibDeflateL() + { +RFs iFs; + iFS.connect(); + + + + //Open input file +_LIT(KInputFileLocation, "c:\\private\\E80000B7\\zip\\input\\input.doc"); +TFileName inputFile(KInputFileLocation); + RFile input; + err = input.Open(iFs, inputFile, EFileStream | EFileRead | EFileShareExclusive); + if(err != KErrNone) + { + INFO_PRINTF1(KOpenFileError); + User::Leave(err); + } + + + + //open output file + +_LIT(KOutputFileLocation, "c:\\private\\E80000B7\\zip\\input\\output.zip"); +TFileName outputFile(KOutputFileLocation); + RFile output; + err = output.Replace(iFs, outputFile, EFileStream | EFileWrite | EFileShareExclusive); + if(err != KErrNone) + { + INFO_PRINTF1(KCreateFileError); + User::Leave(err); + } + + + + CEZFileBufferManager *bufferManager = CEZFileBufferManager::NewLC(input, output); + CEZCompressor *compressor = CEZCompressor::NewLC(*bufferManager, aLevel, aWindowBits, aMemLevel, aStrategy); + + while(compressor->DeflateL()) + { + } + output.Close(); +input.Close(); + iFS.Close(); + + + + } + +

The decompression of a .zip file can be achieved +through the following the steps:

Pass the +input and output files as parameters to construct an instance of CEZFileBufferManager. +This returns a pointer to CEZFileBufferManager ( buffer).
Pass the buffer to the +object of the CEZDecompressor class.
CEZDecompressor::InflateL() is +called repeatedly until the decompression is complete.

The following code demonstrates the decompression procedure.

/* Decompresses the file contained in a Zip file using the EZlib component. + * It is assumed that the input and output file names are contained in a + * provided ini file. + */ + +void CEZlibEZipTests::DoEZlibInflateL() + { +RFs iFs; + iFS.connect(); + +//Open input file +_LIT(KInputFileLocation, "c:\\private\\E80000B7\\zip\\input\\output.zip"); +TFileName inputFile(KInputFileLocation); + RFile input; + err = input.Open(iRfs, inputFile, EFileStream | EFileRead | EFileShareExclusive); + if(err != KErrNone) + { + INFO_PRINTF1(KOpenFileError); + User::Leave(err); + } + + + + //open output file + +_LIT(KOutputFile, "c:\\private\\E80000B7\\zip\\input\\input.doc"); +TFileName outputFile(KOutputFile); + RFile output; + err = output.Replace(iFs, outputFile, EFileStream | EFileWrite | EFileShareExclusive); + if(err != KErrNone) + { + INFO_PRINTF1(KCreateFileError); + User::Leave(err); + } + + + +CEZFileBufferManager *bufferManager = CEZFileBufferManager::NewLC(input, Output); +CEZDecompressor *decompressor = CEZDecompressor::NewLC(*bufferManager, aWindowBits); + + + while(decompressor->InflateL()) + { + } +output.Close(); + input.Close(); + ifs.Close(); + + } \ No newline at end of file