campo-sirio/al/examples/ex18con.c
alex 714dd74636 Archive Library versione 2.00
git-svn-id: svn://10.65.10.50/trunk@5350 c028cbd2-c16b-5b4b-a496-9718f37d4682
1997-10-09 16:09:54 +00:00

167 lines
6.6 KiB
C
Executable File

/*
* EX18CON.C
*
* C/DOS Example program for ArchiveLib 2.0
*
* Copyright (c) Greenleaf Software, Inc. 1994 - 1996
* All Rights Reserved
*
* MEMBERS/FUNCTIONS DEMONSTRATED
*
* newALCompressedObject()
* deleteALCompressed()
* ALCompressedExtract()
* ALCompressedInsert()
* ALCompressedGetStatusCode()
* ALCompressedGetStatusDetail()
* ALCompressedGetStatusString()
* ALCompressedSetError()
* ALStoragePackedAttributes()
* ALStorageSetFromDosAttributes()
* ALStorageSetFromPackedAtts()
* ALStorageSetTimeDateFromUnix()
*
* DESCRIPTION
*
* This is another one of those example programs that ties together
* a bunch of marginally related functions. It starts off by creating
* a data file on disk, and writing some fixed patterns out to it. Next,
* the data file gets inserted into a compressed object, also on disk.
* Then the weird part: If a random number hits, I randomly change a
* byte in the compressed object. Finally, I extract the original data
* file from the compressed object, for better or worse.
*
* After this is all done, I have three TMP files on the disk. In an
* imitation of what you might do in a real debugging situation, I check
* to see if the input and output match. If they do match, I just go
* ahead and delete them, all is well. If they don't match, I want to
* hang on to the files. Not only do I hang on to the files, I give
* them a funny time date stamp, and set them to be read-only.
*
* REVISION HISTORY
*
* February 1, 1996 2.0A : Second release
*
*/
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <conio.h>
#include "al.h"
int main()
{
hALStorage DataFile;
hALStorage CompressedFile;
hALStorage OutputFile;
hALCompressor Compressor;
hALDecompressor Decompressor;
hALCompressed CompressedObject;
int status;
short unsigned int atts;
int i;
int j;
printf( "Archive Library 2.0\nEX18CON.C\n\n" );
printf( "This is another one of those example programs that ties together\n" );
printf( "a bunch of marginally related functions. It starts off by creating\n" );
printf( "a data file on disk, and writing some fixed patterns out to it. Next,\n" );
printf( "the data file gets inserted into a compressed object, also on disk.\n" );
printf( "Then the weird part: If a random number hits, I randomly change a\n" );
printf( "byte in the compressed object. Finally, I extract the original data\n" );
printf( "file from the compressed object, for better or worse.\n\n" );
getch();
#if defined( ZIP )
Compressor = newALPkCompressor( AL_DEFAULT, AL_DEFAULT, AL_DEFAULT );
Decompressor = newALPkDecompressor();
#else
Compressor = newALGlCompressor( AL_DEFAULT, 0 );
Decompressor = newALGlDecompressor( AL_DEFAULT );
#endif
/*
* Here is where I create the input data file and the compressed object.
* This is all fairly realistic, you could write code that looks a lot
* like this.
*/
DataFile = newALFile( "" );
CompressedFile = newALFile( "" );
OutputFile = newALFile( "" );
CompressedObject = newALCompressed( CompressedFile, Compressor, Decompressor );
ALStorageCreate( DataFile, -1 ); /* Temporary file */
for ( i = 0 ; i < 64 ; i++ )
for ( j = i; j < 64 ; j++ )
ALStorageWriteChar( DataFile, j );
ALStorageClose( DataFile );
ALCompressedInsert( CompressedObject, DataFile );
/*
* If the one in four chance hits, I change a single byte in the compressed
* file. This will almost always cause an expansion error, although it
* is possible to create a benign change (like the 1/256 chance that you
* write over the old byte with a new byte that is the same!)
*/
srand( (unsigned) time( NULL ) );
if ( ( rand() & 3 ) == 0 ) {
printf( "Mangling the compressed file!\n" );
ALStorageOpen( CompressedFile );
ALStorageSeek( CompressedFile, 32 + ( rand() & 31 ));
ALStorageWriteChar( CompressedFile, ( rand() & 0xff ) );
ALStorageClose( CompressedFile );
}
/*
* Now I try to extract the output file. Once I have done that, I perform
* a compare to the original to see how things went. Note that there is
* a tricky bit here. The only time ALFile objects will get new time/date
* and attribute stamps is if they are closed immediately after having been
* created. The CompressedObject->Extract() call will create the file,
* then close it. Once it is closed, the flag indicating that it was just
* created will be cleared, so I won't be able to set the time stamp. But,
* if *I* create it here, the Extract() function will leave it open after
* performing its magic. After it returns, I have to close the file,
* but I can mung the time/date stamp first.
*/
ALStorageCreate( OutputFile, AL_DEFAULT );
ALCompressedExtract( CompressedObject, OutputFile );
ALStorageSeek( OutputFile, 0L );
status = ALStorageCompare( DataFile, OutputFile );
printf( "Compare returned : %d\n", status );
/*
* If the comparison passed, I just delete all of the TMP files created
* here. (Note that they all have TMP names because I didn't give them
* any names in their constructors.)
*/
if ( status >= 0 ) {
ALStorageDelete( DataFile );
ALStorageDelete( CompressedFile );
ALStorageClose( OutputFile );
ALStorageDelete( OutputFile );
} else {
ALStorageSetTimeDateFromUnix(
OutputFile,
20L*365L*24L*60L*60L + 5L*24L*60L*60L + 12L*60L*60L );
atts = ALStoragePackedAttributes( OutputFile );
atts = (short unsigned int) ( atts | ATTR_READ_ONLY );
ALStorageSetFromPackedAtts( OutputFile, atts );
ALStorageClose( OutputFile );
ALCompressedSetError( CompressedObject,
status,
ALStorageGetStatusDetail( DataFile ) );
}
printf( "Compressed object status code: %d\n",
ALCompressedGetStatusCode( CompressedObject ) );
printf( "Compressed object status string: %s\n",
ALCompressedGetStatusString( CompressedObject ) );
printf( "Compressed object status detail: %s\n",
ALCompressedGetStatusDetail( CompressedObject ) );
deleteALCompressed( CompressedObject );
deleteALCompressor( Compressor );
deleteALDecompressor( Decompressor );
deleteALStorage( CompressedFile );
deleteALStorage( DataFile );
deleteALStorage( OutputFile );
return status;
}