macstuff.c

给出了 zip 压缩算法的完整实现过程。

/*
These Functions were originally part of More Files version 1.4.8

More Files fixes many of the broken or underfunctional
parts of the file system.

More Files

A collection of File Manager and related routines

by Jim Luther (Apple Macintosh Developer Technical Support Emeritus)
with significant code contributions by Nitin Ganatra
(Apple Macintosh Developer Technical Support Emeritus)
Copyright  1992-1998 Apple Computer, Inc.
Portions copyright  1995 Jim Luther
All rights reserved.

The Package "More Files" is distributed under the following
license terms:

         "You may incorporate this sample code into your
          applications without restriction, though the
          sample code has been provided "AS IS" and the
          responsibility for its operation is 100% yours.
          However, what you are not permitted to do is to
          redistribute the source as "DSC Sample Code" after
          having made changes. If you're going to
          redistribute the source, we require that you make
          it clear in the source that the code was descended
          from Apple Sample Code, but that you've made
          changes."


The following changes are made by Info-ZIP:

- The only changes are made by pasting the functions
  (mostly found in MoreFilesExtras.c / MoreFiles.c)
  directly into macstuff.c / macstuff.h and slightly
  reformatting the text (replacement of TABs by spaces,
  removal/replacement of non-ASCII characters).
  The code itself is NOT changed.

This file has been modified by Info-ZIP for use in MacZip.
This file is NOT part of the original package More Files.

More Files can be found on the MetroWerks CD and Developer CD from
Apple. You can also download the latest version from:

    http://members.aol.com/JumpLong/#MoreFiles

Jim Luther's Home-page:
    http://members.aol.com/JumpLong/


*/

#include <string.h>


#include "macstuff.h"



extern int errno;

static  OSErr   GetCommentFromDesktopFile(short vRefNum,
                                          long dirID,
                                          ConstStr255Param name,
                                          Str255 comment);

static  OSErr   GetCommentID(short vRefNum,
                             long dirID,
                             ConstStr255Param name,
                             short *commentID);

static  OSErr   GetDesktopFileName(short vRefNum,
                                   Str255 desktopName);


enum
{
    kBNDLResType    = 'BNDL',
    kFREFResType    = 'FREF',
    kIconFamResType = 'ICN#',
    kFCMTResType    = 'FCMT',
    kAPPLResType    = 'APPL'
};


/*****************************************************************************/

/*
**  File Manager FSp calls
*/

/*****************************************************************************/

pascal  OSErr   FSMakeFSSpecCompat(short vRefNum,
                                   long dirID,
                                   ConstStr255Param fileName,
                                   FSSpec *spec)
{
    OSErr   result;

#if !__MACOSSEVENORLATER
    if ( !FSHasFSSpecCalls() && !QTHasFSSpecCalls() )
    {
        Boolean isDirectory;

        result = GetObjectLocation(vRefNum, dirID, fileName,
                                    &(spec->vRefNum), &(spec->parID), spec->name,
                                    &isDirectory);
    }
    else
#endif  /* !__MACOSSEVENORLATER */
    {
     /* Let the file system create the FSSpec if it can since it does the job */
     /* much more efficiently than I can. */
        result = FSMakeFSSpec(vRefNum, dirID, fileName, spec);

        /* Fix a bug in Macintosh PC Exchange's MakeFSSpec code where 0 is */
        /* returned in the parID field when making an FSSpec to the volume's */
        /* root directory by passing a full pathname in MakeFSSpec's */
        /* fileName parameter. Fixed in Mac OS 8.1 */
        if ( (result == noErr) && (spec->parID == 0) )
            spec->parID = fsRtParID;
    }
    return ( result );
}


/*****************************************************************************/
/* FSHasFSSpecCalls returns true if the file system provides FSSpec calls. */

#if !__MACOSSEVENORLATER
static  Boolean FSHasFSSpecCalls(void)
{
    long            response;
#if !GENERATENODATA
    static Boolean  tested = false;
    static Boolean  result = false;
#else
    Boolean result = false;
#endif

#if !GENERATENODATA
    if ( !tested )
    {
        tested = true;
#endif
        if ( Gestalt(gestaltFSAttr, &response) == noErr )
        {
            result = ((response & (1L << gestaltHasFSSpecCalls)) != 0);
        }
#if !GENERATENODATA
    }
#endif
    return ( result );
}
#endif  /* !__MACOSSEVENORLATER */



/*****************************************************************************/
/* QTHasFSSpecCalls returns true if QuickTime provides FSSpec calls */
/* except for FSpExchangeFiles. */

#if !__MACOSSEVENORLATER
static  Boolean QTHasFSSpecCalls(void)
{
    long            response;
#if !GENERATENODATA
    static Boolean  tested = false;
    static Boolean  result = false;
#else
    Boolean result = false;
#endif

#if !GENERATENODATA
    if ( !tested )
    {
        tested = true;
#endif
        result = (Gestalt(gestaltQuickTimeVersion, &response) == noErr);
#if !GENERATENODATA
    }
#endif
    return ( result );
}
#endif  /* !__MACOSSEVENORLATER */




/*
 *----------------------------------------------------------------------
 *
 * FSpGetDefaultDir --
 *
 *  This function gets the current default directory.
 *
 * Results:
 *  The provided FSSpec is changed to point to the "default"
 *  directory.  The function returns what ever errors
 *  FSMakeFSSpecCompat may encounter.
 *
 * Side effects:
 *  None.
 *
 *----------------------------------------------------------------------
 */

int FSpGetDefaultDir(FSSpecPtr dirSpec) /* On return the default directory. */
{
    OSErr err;
    short vRefNum = 0;
    long int dirID = 0;

    err = HGetVol(NULL, &vRefNum, &dirID);

    if (err == noErr) {
    err = FSMakeFSSpecCompat(vRefNum, dirID, (ConstStr255Param) NULL,
        dirSpec);
    }

    return err;
}

/*
 *----------------------------------------------------------------------
 *
 * FSpSetDefaultDir --
 *
 *  This function sets the default directory to the directory
 *  pointed to by the provided FSSpec.
 *
 * Results:
 *  The function returns what ever errors HSetVol may encounter.
 *
 * Side effects:
 *  None.
 *
 *----------------------------------------------------------------------
 */

int FSpSetDefaultDir(FSSpecPtr dirSpec) /* The new default directory. */
{
    OSErr err;

    /*
     * The following special case is needed to work around a bug
     * in the Macintosh OS.  (Acutally PC Exchange.)
     */

    if (dirSpec->parID == fsRtParID) {
    err = HSetVol(NULL, dirSpec->vRefNum, fsRtDirID);
    } else {
    err = HSetVol(dirSpec->name, dirSpec->vRefNum, dirSpec->parID);
    }

    return err;
}

/*
 *----------------------------------------------------------------------
 *
 * FSpFindFolder --
 *
 *  This function is a version of the FindFolder function that
 *  returns the result as a FSSpec rather than a vRefNum and dirID.
 *
 * Results:
 *  Results will be simaler to that of the FindFolder function.
 *
 * Side effects:
 *  None.
 *
 *----------------------------------------------------------------------
 */

OSErr
FSpFindFolder(
    short vRefNum,      /* Volume reference number. */
    OSType folderType,      /* Folder type taken by FindFolder. */
    Boolean createFolder,   /* Should we create it if non-existant. */
    FSSpec *spec)       /* Pointer to resulting directory. */
{
    short foundVRefNum;
    long foundDirID;
    OSErr err;

    err = FindFolder(vRefNum, folderType, createFolder,
        &foundVRefNum, &foundDirID);
    if (err != noErr) {
    return err;
    }

    err = FSMakeFSSpecCompat(foundVRefNum, foundDirID, "\p", spec);
    return err;
}



/*
 *----------------------------------------------------------------------
 *
 * FSpPathFromLocation --
 *
 *  This function obtains a full path name for a given macintosh
 *  FSSpec.  Unlike the More Files function FSpGetFullPath, this
 *  function will return a C string in the Handle.  It also will
 *  create paths for FSSpec that do not yet exist.
 *
 * Results:
 *  OSErr code.
 *
 * Side effects:
 *  None.
 *
 *----------------------------------------------------------------------
 */

OSErr
FSpPathFromLocation(
    FSSpec *spec,       /* The location we want a path for. */
    int *length,        /* Length of the resulting path. */
    Handle *fullPath)       /* Handle to path. */
{
    OSErr err;
    FSSpec tempSpec;
    CInfoPBRec pb;

    *fullPath = NULL;

    /*
     * Make a copy of the input FSSpec that can be modified.
     */
    BlockMoveData(spec, &tempSpec, sizeof(FSSpec));

    if (tempSpec.parID == fsRtParID) {
    /*
     * The object is a volume.  Add a colon to make it a full
     * pathname.  Allocate a handle for it and we are done.
     */
    tempSpec.name[0] += 2;
    tempSpec.name[tempSpec.name[0] - 1] = ':';
    tempSpec.name[tempSpec.name[0]] = '\0';

    err = PtrToHand(&tempSpec.name[1], fullPath, tempSpec.name[0]);
    } else {
    /*
     * The object isn't a volume.  Is the object a file or a directory?
     */
    pb.dirInfo.ioNamePtr = tempSpec.name;
    pb.dirInfo.ioVRefNum = tempSpec.vRefNum;
    pb.dirInfo.ioDrDirID = tempSpec.parID;
    pb.dirInfo.ioFDirIndex = 0;
    err = PBGetCatInfoSync(&pb);

    if ((err == noErr) || (err == fnfErr)) {
        /*
         * If the file doesn't currently exist we start over.  If the
         * directory exists everything will work just fine.  Otherwise we
         * will just fail later.  If the object is a directory, append a
         * colon so full pathname ends with colon.
         */
        if (err == fnfErr) {
        BlockMoveData(spec, &tempSpec, sizeof(FSSpec));
        } else if ( (pb.hFileInfo.ioFlAttrib & ioDirMask) != 0 ) {
        tempSpec.name[0] += 1;
        tempSpec.name[tempSpec.name[0]] = ':';
        }

        /*
         * Create a new Handle for the object - make it a C string.
         */
        tempSpec.name[0] += 1;
        tempSpec.name[tempSpec.name[0]] = '\0';
        err = PtrToHand(&tempSpec.name[1], fullPath, tempSpec.name[0]);
        if (err == noErr) {
        /*
         * Get the ancestor directory names - loop until we have an
         * error or find the root directory.
         */
        pb.dirInfo.ioNamePtr = tempSpec.name;
        pb.dirInfo.ioVRefNum = tempSpec.vRefNum;
        pb.dirInfo.ioDrParID = tempSpec.parID;
        do {
            pb.dirInfo.ioFDirIndex = -1;
            pb.dirInfo.ioDrDirID = pb.dirInfo.ioDrParID;
            err = PBGetCatInfoSync(&pb);
            if (err == noErr) {
            /*
             * Append colon to directory name and add
             * directory name to beginning of fullPath.
             */
            ++tempSpec.name[0];
            tempSpec.name[tempSpec.name[0]] = ':';

            (void) Munger(*fullPath, 0, NULL, 0, &tempSpec.name[1],
                tempSpec.name[0]);
            err = MemError();
            }
        } while ( (err == noErr) &&
            (pb.dirInfo.ioDrDirID != fsRtDirID) );
        }
    }
    }

    /*
     * On error Dispose the handle, set it to NULL & return the err.
     * Otherwise, set the length & return.
     */
    if (err == noErr) {
    *length = GetHandleSize(*fullPath) - 1;
    } else {
    if ( *fullPath != NULL ) {
        DisposeHandle(*fullPath);
    }
    *fullPath = NULL;
    *length = 0;
    }

    return err;
}



/*****************************************************************************/

pascal  OSErr   FSpGetDirectoryID(const FSSpec *spec,
                                  long *theDirID,