pjs/xpcom/io/nsFileSpec.h

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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
*
* The contents of this file are subject to the Netscape Public License
* Version 1.0 (the "NPL"); you may not use this file except in
* compliance with the NPL. You may obtain a copy of the NPL at
* http://www.mozilla.org/NPL/
*
* Software distributed under the NPL is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the NPL
* for the specific language governing rights and limitations under the
* NPL.
*
* The Initial Developer of this code under the NPL is Netscape
* Communications Corporation. Portions created by Netscape are
* Copyright (C) 1998 Netscape Communications Corporation. All Rights
* Reserved.
*/
// First checked in on 98/11/20 by John R. McMullen in the wrong directory.
// Checked in again 98/12/04.
// Polished version 98/12/08.
//========================================================================================
//
// Classes defined:
//
// nsFilePath, nsFileURL, nsNativeFileSpec.
//
// This suite provides the following services:
//
// 1. Encapsulates all platform-specific file details, so that files can be
// described correctly without any platform #ifdefs
//
// 2. Type safety. This will fix the problems that used to occur because people
// confused file paths. They used to use const char*, which could mean three
// or four different things. Bugs were introduced as people coded, right up
// to the moment Communicator 4.5 shipped.
//
// 3. Used in conjunction with nsFileStream.h (q.v.), this supports all the power
// and readability of the ansi stream syntax. ALL METHODS OF istream, ostream,
// AND iostream ARE AVAILABLE!
//
// Basic example:
//
// nsFilePath myPath("/Development/iotest.txt");
//
// nsOutputFileStream testStream(myPath);
// testStream << "Hello World" << endl;
//
// 4. Handy methods for manipulating file specifiers safely, e.g. MakeUnique(),
// SetLeafName(), Exists().
//
// 5. Easy cross-conversion.
//
// Examples:
//
// Initialize a URL from a string without suffix
//
// nsFileURL fileURL("file:///Development/MPW/MPW%20Shell");
//
// Initialize a Unix path from a URL
//
// nsFilePath filePath(fileURL);
//
// Initialize a native file spec from a URL
//
// nsNativeFileSpec fileSpec(fileURL);
//
// Make the spec unique (this one has no suffix).
//
// fileSpec.MakeUnique();
//
// Assign the spec to a URL
//
// fileURL = fileSpec;
//
// Assign a unix path using a string with a suffix.
//
// filePath = "/Development/MPW/SysErrs.err";
//
// Assign to a file spec using a unix path.
//
// fileSpec = filePath;
//
// Make this unique (this one has a suffix).
//
// fileSpec.MakeUnique();
//
// 6. Fixes a bug that have been there for a long time, and
// is inevitable if you use NSPR alone, where files are described as paths.
//
// The problem affects platforms (Macintosh) in which a path does not fully
// specify a file, because two volumes can have the same name. This
// is solved by holding a "private" native file spec inside the
// nsFilePath and nsFileURL classes, which is used when appropriate.
//
// Not yet done:
//
// Equality operators... much more.
//
//========================================================================================
#ifndef _FILESPEC_H_
#define _FILESPEC_H_
#include <ostream.h>
//========================================================================================
// Compiler-specific macros, as needed
//========================================================================================
#if defined(__MWERKS__) || defined(XP_PC)
#define NS_USING_NAMESPACE
#endif
#ifdef NS_USING_NAMESPACE
#define NS_NAMESPACE_PROTOTYPE
#define NS_NAMESPACE namespace
#define NS_NAMESPACE_END
using std::ostream;
#else
#define NS_NAMESPACE_PROTOTYPE static
#define NS_NAMESPACE struct
#define NS_NAMESPACE_END ;
#endif
//=========================== End Compiler-specific macros ===============================
#include "nsDebug.h"
#ifdef XP_MAC
#include <Files.h>
#endif
//========================================================================================
// Here are the allowable ways to describe a file.
//========================================================================================
class nsFilePath; // This can be passed to NSPR file I/O routines.
class nsFileURL;
class nsNativeFileSpec;
#define kFileURLPrefix "file://"
#define kFileURLPrefixLength (7)
//========================================================================================
class nsNativeFileSpec
// This is whatever each platform really prefers to describe files as. Declared first
// because the other two types have an embeded nsNativeFileSpec object.
//========================================================================================
{
public:
nsNativeFileSpec();
explicit nsNativeFileSpec(const char* inString);
explicit nsNativeFileSpec(const nsFilePath& inPath);
explicit nsNativeFileSpec(const nsFileURL& inURL);
nsNativeFileSpec(const nsNativeFileSpec& inPath);
virtual ~nsNativeFileSpec();
void operator = (const char* inPath);
void operator = (const nsFilePath& inPath);
void operator = (const nsFileURL& inURL);
void operator = (const nsNativeFileSpec& inOther);
#ifdef XP_MAC
// For Macintosh people, this is meant to be useful in its own right as a C++ version
// of the FSSpec struct.
nsNativeFileSpec(
short vRefNum,
long parID,
ConstStr255Param name);
nsNativeFileSpec(const FSSpec& inSpec)
: mSpec(inSpec), mError(noErr) {}
operator FSSpec* () { return &mSpec; }
operator const FSSpec* const () { return &mSpec; }
operator FSSpec& () { return mSpec; }
operator const FSSpec& () const { return mSpec; }
OSErr Error() const { return mError; }
void MakeAliasSafe();
// Called for the spec of an alias. Copies the alias to
// a secret temp directory and modifies the spec to point
// to it. Sets mError.
void ResolveAlias(bool& wasAliased);
// Called for the spec of an alias. Modifies the spec to
// point to the original. Sets mError.
void MakeUnique(ConstStr255Param inSuggestedLeafName);
StringPtr GetLeafPName() { return mSpec.name; }
ConstStr255Param GetLeafPName() const { return mSpec.name; }
#endif // end of Macintosh utility methods.
#ifdef XP_MAC
bool Valid() const { return mError == noErr; }
#else
bool Valid() const { return true; } // Fixme.
#endif // XP_MAC
friend ostream& operator << (ostream& s, const nsNativeFileSpec& spec);
char* GetLeafName() const; // Allocated. Use delete [].
void SetLeafName(const char* inLeafName);
bool Exists() const;
void MakeUnique();
void MakeUnique(const char* inSuggestedLeafName);
private:
friend class nsFilePath;
#ifdef XP_MAC
FSSpec mSpec;
OSErr mError;
#elif defined(XP_UNIX) || defined(XP_PC)
char* mPath;
#endif
}; // class nsNativeFileSpec
//========================================================================================
class nsFileURL
// This is an escaped string that looks like "file:///foo/bar/mumble%20fish". Since URLs
// are the standard way of doing things in mozilla, this allows a string constructor,
// which just stashes the string with no conversion.
//========================================================================================
{
public:
nsFileURL(const nsFileURL& inURL);
explicit nsFileURL(const char* inString);
explicit nsFileURL(const nsFilePath& inPath);
explicit nsFileURL(const nsNativeFileSpec& inPath);
virtual ~nsFileURL();
// nsString GetString() const { return mPath; }
// may be needed for implementation reasons,
// but should not provide a conversion constructor.
void operator = (const nsFileURL& inURL);
void operator = (const char* inString);
void operator = (const nsFilePath& inOther);
void operator = (const nsNativeFileSpec& inOther);
friend ostream& operator << (ostream& s, const nsFileURL& spec);
#ifdef XP_MAC
// Accessor to allow quick assignment to a mNativeFileSpec
const nsNativeFileSpec& GetNativeSpec() const { return mNativeFileSpec; }
#endif
private:
// Should not be defined (only nsFilePath is to be treated as strings.
operator char* ();
operator const char* const ();
private:
friend class nsFilePath; // to allow construction of nsFilePath
char* mURL;
#ifdef XP_MAC
// Since the path on the macintosh does not uniquely specify a file (volumes
// can have the same name), stash the secret nsNativeFileSpec, too.
nsNativeFileSpec mNativeFileSpec;
#endif
}; // class nsFileURL
//========================================================================================
class nsFilePath
// This is a string that looks like "/foo/bar/mumble%20fish". Same as nsFileURL, but
// without the "file:// prefix".
//========================================================================================
{
public:
nsFilePath(const nsFilePath& inPath);
explicit nsFilePath(const char* inString);
explicit nsFilePath(const nsFileURL& inURL);
explicit nsFilePath(const nsNativeFileSpec& inPath);
virtual ~nsFilePath();
operator const char* () const { return mPath; }
// This is the only automatic conversion to const char*
// that is provided, and it allows the
// path to be "passed" to NSPR file routines.
operator char* () { return mPath; }
// This is the only automatic conversion to string
// that is provided, because a naked string should
// only mean a standard file path.
void operator = (const nsFilePath& inPath);
void operator = (const char* inString);
void operator = (const nsFileURL& inURL);
void operator = (const nsNativeFileSpec& inOther);
#ifdef XP_MAC
public:
// Accessor to allow quick assignment to a mNativeFileSpec
const nsNativeFileSpec& GetNativeSpec() const { return mNativeFileSpec; }
#endif
private:
char* mPath;
#ifdef XP_MAC
// Since the path on the macintosh does not uniquely specify a file (volumes
// can have the same name), stash the secret nsNativeFileSpec, too.
nsNativeFileSpec mNativeFileSpec;
#endif
}; // class nsFilePath
#endif // _FILESPEC_H_