pathname.c

给出了 zip 压缩算法的完整实现过程。

/*
  Copyright (c) 1990-2005 Info-ZIP.  All rights reserved.

  See the accompanying file LICENSE, version 2004-May-22 or later
  (the contents of which are also included in zip.h) for terms of use.
  If, for some reason, both of these files are missing, the Info-ZIP license
  also may be found at:  ftp://ftp.info-zip.org/pub/infozip/license.htmlhtml
*/
/*---------------------------------------------------------------------------

  pathname.c

  Function dealing with the pathname. Mostly C-string work.

  ---------------------------------------------------------------------------*/

/*****************************************************************************/
/*  Includes                                                                 */
/*****************************************************************************/

#include <string.h>
#include <stdio.h>
#include <unistd.h>
#include <sound.h>

#include "pathname.h"
#include "helpers.h"
#include "macstuff.h"


/*****************************************************************************/
/*  Global Vars                                                              */
/*****************************************************************************/

const char  ResourceMark[] = "XtraStuf.mac:";  /* see also macos.c */


#include "zip.h"




/*****************************************************************************/
/*  Functions                                                                */
/*****************************************************************************/




/*
**  return volumename from pathname
**
*/

unsigned short GetVolumeFromPath(const char *FullPath, char *VolumeName)
{
const char *VolEnd, *tmpPtr1;
char *tmpPtr2 = VolumeName;

AssertStr(FullPath,"GetVolumeFromPath")

for (VolEnd = FullPath; *VolEnd != '\0' && *VolEnd != ':'; VolEnd++)
      ;
if (*VolEnd == '\0') return 0;

for (tmpPtr1 = FullPath; tmpPtr1 != VolEnd;)
    {
    *tmpPtr2++ = *tmpPtr1++;
    }

*tmpPtr2 = '\0';

return (unsigned short) strlen(VolumeName);
}



/***********************************/
/* Function FindNewExtractFolder() */
/***********************************/

char *FindNewExtractFolder(char *ExtractPath)
{
char buffer[NAME_MAX], *tmpPtr, *namePtr;
short count = 0, folderCount = 0;
OSErr err;
FSSpec Spec;
long theDirID;
Boolean isDirectory;
unsigned short namelen, pathlen = strlen(ExtractPath);

AssertStr(ExtractPath,"FindNewExtractFolder ExtractPath == NULL")

for (tmpPtr = ExtractPath; *tmpPtr; tmpPtr++)
    if (*tmpPtr == ':')
        {
        folderCount++;
        namePtr = tmpPtr;
        }

if (folderCount > 1)
    namelen = strlen(namePtr);
else
    namelen = strlen(ExtractPath);

for (count = 0; count < 99; count++)
    {
    memset(buffer,0,sizeof(buffer));

    if (namelen >= 28)
        ExtractPath[pathlen-2] = 0x0;
    else
        ExtractPath[pathlen-1] = 0x0;

    sprintf(buffer,"%s%d",ExtractPath,count);
    GetCompletePath(ExtractPath, buffer, &Spec,&err);
    err = FSpGetDirectoryID(&Spec, &theDirID, &isDirectory);
    if (err == -43) break;
    }

/* Foldernames must always end with a colon  */
sstrcat(ExtractPath,":");
return ExtractPath;
}



/*
**  creates an archive file name
**
*/

void createArchiveName(char *thePath)
{
char *tmpPtr, *namePtr;
short folderCount = 0;
unsigned short namelen, pathlen = strlen(thePath);

if (thePath[pathlen-1] == ':') thePath[pathlen-1] = 0x0;

for (tmpPtr = thePath; *tmpPtr; tmpPtr++)
    if (*tmpPtr == ':')
        {
        folderCount++;
        namePtr = tmpPtr;
        }

namelen = strlen(namePtr);

    /* we have to eliminate illegal chars:
     * The name space for Mac filenames and Zip filenames (unix style names)
     * do both include all printable extended-ASCII characters.  The only
     * difference we have to take care of is the single special character
     * used as path delimiter:
     * ':' on MacOS and '/' on Unix and '\' on Dos.
     * So, to convert between Mac filenames and Unix filenames without any
     * loss of information, we simply interchange ':' and '/'.  Additionally,
     * we try to convert the coding of the extended-ASCII characters into
     * InfoZip's standard ISO 8859-1 codepage table.
     */
  MakeCompatibleString(namePtr, '/', '_', '.', '-', -1);

 /* Avoid filenames like: "Archive..zip"  */
if (thePath[pathlen-1] == '.')
    {
    thePath[pathlen-1] = 0;
    }

if (folderCount >= 1)
    { /* path contains at least one folder */

    if (namelen >= 28)
        {
        pathlen = pathlen-4;
        }

    thePath[pathlen]   = '.';
    thePath[pathlen+1] = 'z';
    thePath[pathlen+2] = 'i';
    thePath[pathlen+3] = 'p';
    thePath[pathlen+4] = 0x0;
    return;
    }
else
    {  /* path contains no folder */
    FindDesktopFolder(thePath);
    createArchiveName(thePath);
    }
}



/*
** finds the desktop-folder on a volume with
** largest amount of free-space.
*/

void FindDesktopFolder(char *Path)
{
char buffer[255];
FSSpec  volumes[50];        /* 50 Volumes should be enough */
short   actVolCount, volIndex = 1, VolCount = 0;
OSErr   err;
short     i, foundVRefNum;
FSSpec spec;
UnsignedWide freeBytes;
UnsignedWide totalBytes;
UnsignedWide MaxFreeBytes;

err = OnLine(volumes, 50, &actVolCount, &volIndex);
printerr("OnLine:", (err != -35) && (err != 0), err, __LINE__, __FILE__, "");

MaxFreeBytes.hi = 0;
MaxFreeBytes.lo = 0;

for (i=0; i < actVolCount; i++)
    {
    XGetVInfo(volumes[i].vRefNum,
              volumes[i].name,
              &volumes[i].vRefNum,
              &freeBytes,
              &totalBytes);

    if (MaxFreeBytes.hi < freeBytes.hi) {
        MaxFreeBytes.hi = freeBytes.hi;
        MaxFreeBytes.lo = freeBytes.lo;
        foundVRefNum = volumes[i].vRefNum;
    }

    if ((freeBytes.hi == 0) && (MaxFreeBytes.lo < freeBytes.lo)) {
        MaxFreeBytes.hi = freeBytes.hi;
        MaxFreeBytes.lo = freeBytes.lo;
        foundVRefNum = volumes[i].vRefNum;
    }

}

 FSpFindFolder(foundVRefNum, kDesktopFolderType,
            kDontCreateFolder,&spec);

 GetFullPathFromSpec(buffer, &spec , &err);
 sstrcat(buffer,Path);
 sstrcpy(Path,buffer);
}


/*
**  return the path without the filename
**
*/

char *TruncFilename(char *DirPath, const char *FilePath)
{
char *tmpPtr;
char *dirPtr = NULL;

AssertStr(DirPath,"TruncFilename")
Assert_it(Spec,"TruncFilename","")

sstrcpy(DirPath, FilePath);

for (tmpPtr = DirPath; *tmpPtr; tmpPtr++)
    if (*tmpPtr == ':')
        dirPtr = tmpPtr;

if (dirPtr)
    *++dirPtr = '\0';
else
    printerr("TruncFilename: FilePath has no Folders", -1,
         -1, __LINE__, __FILE__, FilePath);

return DirPath;
}



/*
**  return only filename
**
*/

char *GetFilename(char *FileName, const char *FilePath)
{
const char *tmpPtr;
const char *dirPtr = NULL;

Assert_it(FileName,"GetFilename","")
Assert_it(FilePath,"GetFilename","")

for (tmpPtr = FilePath; *tmpPtr; tmpPtr++)
    {
    if (*tmpPtr == ':')
        {
        dirPtr = tmpPtr;
        }
    }

if (dirPtr)
    {
    ++dirPtr;  /* jump over the ':' */
    }
else
    {
    return strcpy(FileName, FilePath); /* FilePath has no Folders */
    }

return strcpy(FileName, dirPtr);
}



/*
**  return fullpathname from folder/dir-id
**
*/

char *GetFullPathFromID(char *CompletePath, short vRefNum, long dirID,
                        ConstStr255Param name, OSErr *err)
{
FSSpec      spec;

    *err = FSMakeFSSpecCompat(vRefNum, dirID, name, &spec);
    printerr("FSMakeFSSpecCompat:", (*err != -43) && (*err != 0), *err,
             __LINE__, __FILE__, "");
    if ( (*err == noErr) || (*err == fnfErr) )
        {
        return GetFullPathFromSpec(CompletePath, &spec, err);
        }

return NULL;
}