directory.h

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#ifndef _DIRECTORY_H
#define _DIRECTORY_H


//
// author: Owen Astrachan
// date:  9/21/93
//
// modified 11/28/94
// modified  4/5/95
// modified 1/18/96
// modified 5/10/99, ported to 32-bit windows
//
// classes for manipulating directories
// provide a standard interface for directory
// queries from C++ programs that can, in theory, be implemented
// on several platforms
//
// currently supported: Unix, DOS, Windows
//
// the class DirEntry provides directory information
// accessible via methods Name, Size, and IsDir
//
// the class DirStream does I/O on directories
// it supports "standard" (for the Tapestry book)
// iterator methods/member functions
//

// *********  DirEntry member functions:
//
// string Name() -- returns name of file
// int Size()    -- returns size of file (in bytes)
// bool IsDir()  -- returns false if NOT directory, else true
// string Path() -- returns full path to file
// DirEntry()    -- constructor, directory entry undefined attributes

// *********  DirStream member functions:
//
// DirStream(string name) -- constructor (pass name of directory)
// DirStream()            -- default constructor (use current directory)
// void open(string name) -- opens directory stream with given name
// bool fail()            -- returns true if directory operations has
//                           failed, else returns false
// void close()           -- close stream
//
//
// void Init()           -- set DirStream so first entry is accessible
// bool HasMore()        -- returns true if current ok, else false
// void Next()            -- advance to next entry
// DirEntry Current()     -- return current directory entry
//                           call only when HasMore = true

#include <string>
using namespace std;

const string DIR_SEPARATOR = "\\";  // platform specific

class DirStream;     // need forward reference for friendship
class WIN32_DATA;    // defined in .cpp file (avoid parsing huge <windows.h>

#include "date.h"
#include "clockt.h"

class DirEntry
{
  public:
    DirEntry();                      // constructor
    ~DirEntry();                     // destructor
    
    string Name() const;        // return name (not full path) of file
    string Path() const;        // return canonicalized path of file
	long  Size()  const;        // return size (bytes) of file
    bool IsDir()  const;        // return false if file, true if directory
    Date GetDate()   const;
    ClockTime GetTime() const;
    friend DirStream;     // class has access to internals
        
  private:
    
    // this is the private directory entry information
    // it is platform specific, probably should be a 'handle'
    // to a class PrivateDirEntry defined in directory.cc

    DirEntry(WIN32_DATA* dat); // from platform-specific constructor

    string myName;               // NOT full path, just 'file' name
    string myPath;               // full, canonicalized path
    Date   myDate;               // creation date
    ClockTime myTime;            // creation time
	long mySize;                 // in bytes
    bool myIsDirectory;          // true if directory, else false
};

class HHandle;  // forward, really a HANDLE, but avoid parsing <windows.h>

class DirStream
{

  public:
    DirStream(const string & name);  // name is path to directory
    DirStream();                     // current directory
    ~DirStream();                    // destructor
    void open(const string & name);  // open, bind to file with name
    void close();                    // close the stream
    bool fail();                     // return true if failed, else false

    void Init();                    // standard iterator functions
    void Next();
    bool HasMore();
    DirEntry Current();
        
    // stuff below is 'esoteric' C++
    //
    // the () method returning void * is what allows
    // the expression: while (dirstream)
    // to work [see Teale, The I/O Stream Handbook]
    
    operator void *() const
    {
        return myStatus ? (void *) this : (void *) 0;
    };

    // allow the expression if (!dirstream)
    
    int operator !() const
    {
        return !myStatus; 
    }

  private:
      
    HHandle  *   myStream;  // for Windows
    WIN32_DATA * myData;    // for Windows
    bool     myStatus;      // if true, everything ok, else all done
    string   myPath;        // full path to this directory
    DirEntry myEntry;       // cached, current entry
    bool     myIsClosed;    // already closed myStream?
	    
	void Initialize(const string & s);  // private init commonality
    void SetEntry();                    // common code (Init/Next)
    
   // disable assignment and copy
 
    DirStream operator = (const DirStream & dir);
    DirStream(const DirStream & dir);
};

#endif /*  _DIRECTORY_H not defined */