gecko/netwerk/base/src/nsFileStreams.h

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#ifndef nsFileStreams_h__
#define nsFileStreams_h__

#include "nsIFileStreams.h"
#include "nsIFile.h"
#include "nsIInputStream.h"
#include "nsIOutputStream.h"
#include "nsISafeOutputStream.h"
#include "nsISeekableStream.h"
#include "nsILineInputStream.h"
#include "nsCOMPtr.h"
#include "prlog.h"
#include "prio.h"

template<class CharType> class nsLineBuffer;

////////////////////////////////////////////////////////////////////////////////

class nsFileStream : public nsISeekableStream
{
public:
    NS_DECL_ISUPPORTS
    NS_DECL_NSISEEKABLESTREAM

    nsFileStream();
    virtual ~nsFileStream();

    nsresult Close();
    nsresult InitWithFileDescriptor(PRFileDesc* fd, nsISupports* parent);

protected:
    PRFileDesc*           mFD;
    nsCOMPtr<nsISupports> mParent; // strong reference to parent nsFileIO,
                                   // which ensures mFD remains valid.
    PRBool                mCloseFD;
};

////////////////////////////////////////////////////////////////////////////////

class nsFileInputStream : public nsFileStream,
                          public nsIFileInputStream,
                          public nsILineInputStream
{
public:
    NS_DECL_ISUPPORTS_INHERITED
    NS_DECL_NSIINPUTSTREAM
    NS_DECL_NSIFILEINPUTSTREAM
    NS_DECL_NSILINEINPUTSTREAM
    
    // Overrided from nsFileStream
    NS_IMETHOD Seek(PRInt32 aWhence, PRInt64 aOffset);

    nsFileInputStream() : nsFileStream() 
    {
        mLineBuffer = nsnull;
        mBehaviorFlags = 0;
    }
    virtual ~nsFileInputStream() 
    {
        Close();
    }

    static NS_METHOD
    Create(nsISupports *aOuter, REFNSIID aIID, void **aResult);

protected:
    nsLineBuffer<char> *mLineBuffer;

    /**
     * The file being opened.  Only stored when DELETE_ON_CLOSE or
     * REOPEN_ON_REWIND are true.
     */
    nsCOMPtr<nsIFile> mFile;
    /**
     * The IO flags passed to Init() for the file open.
     * Only set for REOPEN_ON_REWIND.
     */
    PRInt32 mIOFlags;
    /**
     * The permissions passed to Init() for the file open.
     * Only set for REOPEN_ON_REWIND.
     */
    PRInt32 mPerm;
    /**
     * Flags describing our behavior.  See the IDL file for possible values.
     */
    PRInt32 mBehaviorFlags;

protected:
    /**
     * Internal, called to open a file.  Parameters are the same as their
     * Init() analogues.
     */
    nsresult Open(nsIFile* file, PRInt32 ioFlags, PRInt32 perm);
    /**
     * Reopen the file (for OPEN_ON_READ only!)
     */
    nsresult Reopen() { return Open(mFile, mIOFlags, mPerm); }
};

////////////////////////////////////////////////////////////////////////////////

class nsFileOutputStream : public nsFileStream,
                           public nsIFileOutputStream
{
public:
    NS_DECL_ISUPPORTS_INHERITED
    NS_DECL_NSIOUTPUTSTREAM
    NS_DECL_NSIFILEOUTPUTSTREAM

    nsFileOutputStream() : nsFileStream() {}
    virtual ~nsFileOutputStream() { nsFileOutputStream::Close(); }
    
    static NS_METHOD
    Create(nsISupports *aOuter, REFNSIID aIID, void **aResult);
};

////////////////////////////////////////////////////////////////////////////////

class nsSafeFileOutputStream : public nsFileOutputStream,
                               public nsISafeOutputStream
{
public:
    NS_DECL_ISUPPORTS_INHERITED
    NS_DECL_NSISAFEOUTPUTSTREAM

    nsSafeFileOutputStream() :
        mTargetFileExists(PR_TRUE),
        mWriteResult(NS_OK) {}

    virtual ~nsSafeFileOutputStream() { nsSafeFileOutputStream::Close(); }

    NS_IMETHODIMP Close();
    NS_IMETHODIMP Write(const char *buf, PRUint32 count, PRUint32 *result);
    NS_IMETHODIMP Init(nsIFile* file, PRInt32 ioFlags, PRInt32 perm, PRInt32 behaviorFlags);

protected:
    nsCOMPtr<nsIFile>         mTargetFile;
    nsCOMPtr<nsIFile>         mTempFile;

    PRBool   mTargetFileExists;
    nsresult mWriteResult; // Internally set in Write()
};

////////////////////////////////////////////////////////////////////////////////

#endif // nsFileStreams_h__