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#ifndef CYGONCE_LIBC_STDIO_STREAM_INL

#define CYGONCE_LIBC_STDIO_STREAM_INL

//========================================================================

//

//      stream.inl

//

//      Inline functions for internal C library stdio stream interface

//

//========================================================================

// ####ECOSGPLCOPYRIGHTBEGIN####

// -------------------------------------------

// This file is part of eCos, the Embedded Configurable Operating System.

// Copyright (C) 1998, 1999, 2000, 2001, 2002 Free Software Foundation, Inc.

//

// eCos 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 or (at your option) any later

// version.

//

// eCos 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 eCos; if not, write to the Free Software Foundation, Inc.,

// 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.

//

// As a special exception, if other files instantiate templates or use

// macros or inline functions from this file, or you compile this file

// and link it with other works to produce a work based on this file,

// this file does not by itself cause the resulting work to be covered by

// the GNU General Public License. However the source code for this file

// must still be made available in accordance with section (3) of the GNU

// General Public License v2.

//

// This exception does not invalidate any other reasons why a work based

// on this file might be covered by the GNU General Public License.

// -------------------------------------------

// ####ECOSGPLCOPYRIGHTEND####

//========================================================================

//#####DESCRIPTIONBEGIN####

//

// Author(s):     jlarmour

// Contributors:

// Date:          2000-04-19

// Purpose:

// Description:

// Usage:         Do not include this file -

//                #include  instead.

//

//####DESCRIPTIONEND####

//

//========================================================================

// CONFIGURATION

#include     // Configuration header

// INCLUDES

#include     // Common project-wide type definitions

#include                 // NULL and size_t from compiler

#include                  // Error codes

#include  // Just be sure that this really is

                                   // included

#include      // I/O system inlines

// FUNCTIONS

#ifdef CYGDBG_USE_ASSERTS

inline cyg_bool

Cyg_StdioStream::check_this( cyg_assert_class_zeal zeal ) const

{

    // check that it has the magic word set meaning it is valid.

    if ( magic_validity_word != 0x7b4321ce )

        return false;

    return true;

} // check_this()

#endif // ifdef CYGDBG_USE_ASSERTS

// LOCKING FUNCTIONS

// returns true on success

inline cyg_bool

Cyg_StdioStream::lock_me( void )

{

    CYG_ASSERTCLASS( this, "Stream object is not a valid stream!" );

#ifdef CYGSEM_LIBC_STDIO_THREAD_SAFE_STREAMS

    return stream_lock.lock();

#else

    // otherwise it "worked"

    return true;

#endif

} // lock_me()

// returns true on success

inline cyg_bool

Cyg_StdioStream::trylock_me( void )

{

    CYG_ASSERTCLASS( this, "Stream object is not a valid stream!" );

#ifdef CYGSEM_LIBC_STDIO_THREAD_SAFE_STREAMS

    return stream_lock.trylock();

#else

    // otherwise it "worked"

    return true;

#endif

} // lock_me()

inline void

Cyg_StdioStream::unlock_me( void )

{

    CYG_ASSERTCLASS( this, "Stream object is not a valid stream!" );

#ifdef CYGSEM_LIBC_STDIO_THREAD_SAFE_STREAMS

    stream_lock.unlock();

#endif

} // unlock_me()

// DESTRUCTOR

inline Cyg_ErrNo

Cyg_StdioStream::close()

{

    Cyg_ErrNo err = ENOERR;

    if (!lock_me())

        return EBADF;

    if( my_device != CYG_STDIO_HANDLE_NULL )

    {

        flush_output_unlocked();

        err = cyg_stdio_close( my_device );

        if( err == ENOERR )

            my_device = CYG_STDIO_HANDLE_NULL;

    }

    unlock_me();

    return err;

} // close()

inline

Cyg_StdioStream::~Cyg_StdioStream()

{

    CYG_ASSERTCLASS( this, "Stream object is not a valid stream!" );

    // Close the device if it has not already been closed.

    if( my_device != CYG_STDIO_HANDLE_NULL )

        close();

#ifdef CYGDBG_USE_ASSERTS

    magic_validity_word = 0xbadbad;

#endif

} // Cyg_StdioStream destructor

// MEMBER FUNCTIONS

// this is currently just a wrapper around write, but having this interface

// leaves scope for optimisations in future

inline Cyg_ErrNo

Cyg_StdioStream::write_byte( cyg_uint8 c )

{

    cyg_ucount32 dummy_bytes_written;

    Cyg_ErrNo err;

    CYG_ASSERTCLASS( this, "Stream object is not a valid stream!" );

    err = write( &c, 1, &dummy_bytes_written );

    CYG_ASSERT( (err!=ENOERR) || (dummy_bytes_written==1),

                "Single byte not written, but no error returned!" );

    return err;

} // write_byte()

inline Cyg_ErrNo

Cyg_StdioStream::unread_byte( cyg_uint8 c )

{

    CYG_ASSERTCLASS( this, "Stream object is not a valid stream!" );

#ifdef CYGFUN_LIBC_STDIO_ungetc

    if (!lock_me())

        return EBADF;  // assume file is now invalid

    if (flags.unread_char_buf_in_use) {

        unlock_me();

        return ENOMEM;

    } // if

    flags.unread_char_buf_in_use = true;

    unread_char_buf = c;

    // can't be at EOF any more

    flags.at_eof = false;

    if (position)    // position is always 0 for certain devices

        --position;

    unlock_me();

    return ENOERR;

#else // ifdef CYGFUN_LIBC_STDIO_ungetc

    return ENOSYS;

#endif // ifdef CYGFUN_LIBC_STDIO_ungetc

} // unread_byte()

inline cyg_ucount32

Cyg_StdioStream::bytes_available_to_read( void )

{

    cyg_ucount32 bytes=0;

    CYG_ASSERTCLASS( this, "Stream object is not a valid stream!" );

#ifdef CYGFUN_LIBC_STDIO_ungetc

    if (flags.unread_char_buf_in_use)

        ++bytes;

#endif

#ifdef CYGSEM_LIBC_STDIO_WANT_BUFFERED_IO

    // either the last operation was a read, which attempted to read bytes

    // into the buffer, or there are no bytes in the buffer

    if (flags.buffering) {

        if (flags.last_buffer_op_was_read == true)

            bytes += io_buf.get_buffer_space_used();

    }

    else

#endif

    if (flags.readbuf_char_in_use)

        ++bytes;

    return bytes;

} // bytes_available_to_read()

inline Cyg_ErrNo

Cyg_StdioStream::flush_output( void )

{

    Cyg_ErrNo err;

    CYG_ASSERTCLASS( this, "Stream object is not a valid stream!" );

    if (!lock_me())

        return EBADF;  // assume file is now invalid

    err = flush_output_unlocked();

    unlock_me();

    return err;

} // flush_output()

// get error status for this file

inline Cyg_ErrNo

Cyg_StdioStream::get_error( void )

{

    Cyg_ErrNo err_temp;

    CYG_ASSERTCLASS( this, "Stream object is not a valid stream!" );

    if (!lock_me())

        return EBADF;     // well, we've certainly got an error now!

    err_temp = error;

    unlock_me();

    return err_temp;

} // get_error()

// set error status for this file

inline void

Cyg_StdioStream::set_error( Cyg_ErrNo errno_to_set )

{

    CYG_ASSERTCLASS( this, "Stream object is not a valid stream!" );

    if (!lock_me())

    {

        errno = EBADF; // best we can do - we can't trust error to be there

        return;

    } // if

    errno = error = errno_to_set;

    if ( EEOF == error )

        flags.at_eof = 1;

    unlock_me();

} // set_error()

// are we at EOF? true means we are, false means no

inline cyg_bool

Cyg_StdioStream::get_eof_state( void )

{

    cyg_bool eof_temp;

    CYG_ASSERTCLASS( this, "Stream object is not a valid stream!" );

    if (!lock_me())

        return false;     // not much we can do here

    eof_temp = flags.at_eof;

    unlock_me();

    return eof_temp;

} // get_eof_state()

// Set whether we are at EOF.

inline void

Cyg_StdioStream::set_eof_state( cyg_bool eof_to_set )

{

    CYG_ASSERTCLASS( this, "Stream object is not a valid stream!" );

    if (!lock_me())

        return;     // not much we can do here

    flags.at_eof = eof_to_set;

    unlock_me();

} // set_eof_state()

// retrieve position

inline Cyg_ErrNo

Cyg_StdioStream::get_position( fpos_t *pos )

{

    CYG_ASSERTCLASS( this, "Stream object is not a valid stream!" );

    if (!lock_me())

        return EBADF; // assume file is now invalid

    *pos = position;

    unlock_me();

    return ENOERR;

} // get_position()

// set absolute position

inline Cyg_ErrNo

Cyg_StdioStream::set_position( fpos_t pos, int whence )

{

    CYG_ASSERTCLASS( this, "Stream object is not a valid stream!" );

#ifndef CYGPKG_LIBC_STDIO_FILEIO

    // this is currently a workaround until we have real files

    // this will be corrected when we decide the true filesystem interface

    Cyg_ErrNo err;

    cyg_uint8 c;

    if ((whence != SEEK_CUR) || pos < 0)

        return ENOSYS;

    if (!lock_me())

        return EBADF; // assume file is now invalid

    // Drain read buffer

    for ( ; pos > 0 ; pos-- ) {

        err = read_byte( &c );

        if (err == EAGAIN)

            err=refill_read_buffer();

        // if read_byte retured error, or refill_read_buffer returned error

        if (err) {

            unlock_me();

            return err;

        } // if

    } // for

    unlock_me();

    return ENOERR;

#else

    if (!lock_me())

        return EBADF; // assume file is now invalid

    if ( whence != SEEK_END ) {

        off_t bytesavail = (off_t)bytes_available_to_read();

        off_t abspos = (whence == SEEK_CUR) ? position + pos : pos;

        off_t posdiff = abspos - position;

        if ( posdiff >= 0 && bytesavail > posdiff ) {

            // can just "seek" within the existing buffer

#ifdef CYGFUN_LIBC_STDIO_ungetc

            if (posdiff>0 && flags.unread_char_buf_in_use) {

                flags.unread_char_buf_in_use = false;

                posdiff--;

            }

#endif

#ifdef CYGSEM_LIBC_STDIO_WANT_BUFFERED_IO

            if (posdiff>0 && flags.buffering) {

                io_buf.set_bytes_read(posdiff);

                posdiff=0;

            } else

#endif

            if (posdiff>0 && flags.readbuf_char_in_use) {

                flags.readbuf_char_in_use = false;

                posdiff--;

            }

            CYG_ASSERT(posdiff==0, "Failed to seek within buffer correctly");

            position = abspos;

            unlock_me();

            return ENOERR;

        } // endif (bytesavail > posdiff)

        if (whence == SEEK_CUR) {

            position += bytesavail;

            pos -= bytesavail;

        }

    } //endif (whence != SEEK_END)

    Cyg_ErrNo err;

    // Flush output if any present.

    err = flush_output_unlocked();

    if( err == ENOERR )

    {

        off_t newpos=pos;

        // Clear any input out of input buffer and any ungot chars

        // from unread buffer.

        io_buf.drain_buffer();

#ifdef CYGFUN_LIBC_STDIO_ungetc

        flags.unread_char_buf_in_use = false;

#endif

        // Clear EOF indicator.

        flags.at_eof = false;

        // Seek the file to the correct place

        err = cyg_stdio_lseek( my_device, &newpos, whence );

        if ( err == ENOERR) {

          // update stream pos

          position = newpos;

        }

    }

    unlock_me();

    return err;

#endif

} // set_position()

#endif // CYGONCE_LIBC_STDIO_STREAM_INL multiple inclusion protection

// EOF stream.inl