cstdio.h

研读AxCrypt对加解密的处理方法

#ifndef CSTDIO_H
#define CSTDIO_H
/*! \file CStdIO.h
    \brief Standard Input and Output Source and Sink, AxPipe::CSourceStdIn and AxPipe::CSinkStdOut

    @(#) $Id$

    AxPipe - Binary Stream Framework

    Copyright (C) 2003 Svante Seleborg/Axon Data, All rights reserved.

    This program is free software; you can redistribute it and/or modify it under the terms
    of the GNU General Public License as published by the Free Software Foundation;
    either version 2 of the License, or (at your option) any later version.

    This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
    without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
    See the GNU General Public License for more details.

    You should have received a copy of the GNU General Public License along with this program;
    if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
    Boston, MA 02111-1307 USA

    The author may be reached at mailto:[e-mail] and http://axpipe.sourceforge.net

    Why is this framework released as GPL and not LGPL? See http://www.gnu.org/philosophy/why-not-lgpl.html

----
\verbatim
    CStdIO.h                        Standard Input and Output Source and Sink

    E-mail                          YYYY-MM-DD              Reason
    [e-mail]              2004-09-12              Initial
\endverbatim

    AxPipe Standard Input and Output source and sink classes.

    C[T]SourceStdIn  - a source [in it's own thread]
    C[T]SinkStdOut   - a sink [in it's own thread]

    Copyright 2003, Axon Data/Svante Seleborg, All Rights Reserved.
*/
#include    "AxPipe.h"
#include    <stdio.h>
#include    <stdlib.h>

#include "AxAssert.h"
#define AXLIB_ASSERT_FILE "CStdIO.h"

namespace AxPipe {

/// \brief A CSource providing data from standard input
class CSourceStdIn : public CSource {
    size_t m_cbChunk;                       // The reading chunk-size
public:
    /// \brief Set chunk size
    /// \param fBinary set to true for binary style reading
    /// \param cbChunk the size of the read buffer
    /// \return A pointer to this
    CSourceStdIn *Init(bool fBinary = false, size_t cbChunk = 64*1024) {
        m_cbChunk = cbChunk;
        ASSCHK(setmode(fileno(stdin), fBinary ? O_BINARY : O_TEXT) != -1, _T("CSourceStdIn::Init() setmode() failed"));
        return this;
    }

    /// \brief Set chunk size to default and stream-mode
    /// \param fBinary set to true binary style access
    CSourceStdIn(bool fBinary = false) {
        Init(fBinary);
    }

protected:
    ///< Get the next chunk from the input file
    /// \return data, or zero-length on EOF or NULL on error
    CSeg *In() {
        if (ferror(stdin)) {
            return NULL;
        }
        if (feof(stdin)) {
            return new CSeg(0);
        }
        CSeg *pSeg = new CSeg(m_cbChunk);
        size_t cbLen = fread(pSeg->PtrWr(), 1, pSeg->Size(), stdin);
        if (cbLen < pSeg->Size()) {
            if (ferror(stdin)) {
                pSeg->Release();
                return NULL;
            }
        }
        // Just return the amount of data we actually got. If it's zero for eof that's ok too.
        pSeg->Len(cbLen);
        return pSeg;
    }
};

/// \brief A CSink writing data to standard output
class CSinkStdOut : public CSink {
public:
    /// \brief Set file mode
    /// \param fBinary Set to true for binary mode writing
    /// \return A pointer to this
    CSinkStdOut *Init(bool fBinary = false) {
        ASSCHK(setmode(fileno(stdout), fBinary ? O_BINARY : O_TEXT) != -1, _T("CSourceStdOut::Init() setmode() failed"));
        return this;
    }

    // Set default mode (text)
    CSinkStdOut(){
        Init();
    }

    /// \brief output a segment
    /// Check with CError::GetErrorCode() and CError::GetErrorMsg() for errors
    /// \param pSeg The segment to write
    virtual void Out(CSeg *pSeg) {
        size_t cbLen = fwrite(pSeg->PtrRd(), 1, pSeg->Len(), stdout);
        if (cbLen != pSeg->Len()) {
            SetError(ERROR_CODE_GENERIC, _T("CSinkStdOut::fwrite failed [%s]"), strerror(errno));
        }
    }
};

} // namespace AxPipe;
#endif