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

//

//      gets.cxx

//

//      ISO C standard I/O gets() function

//

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

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

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

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

//

// Author(s):     jlarmour

// Contributors: 

// Date:          2001-03-15

// Purpose:       Implementation of ISO C standard I/O gets() function

// Description: 

// Usage:       

//

//####DESCRIPTIONEND####

//

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

// CONFIGURATION

#include <pkgconf/libc_stdio.h>   // Configuration header

// INCLUDES

#include <cyg/infra/cyg_type.h>     // Common type definitions

#include <cyg/infra/cyg_ass.h>      // Assertion support

#include <cyg/infra/cyg_trac.h>     // Tracing support

#include <stddef.h>                 // NULL and size_t from compiler

#include <stdio.h>                  // header for this file

#include <errno.h>                  // error codes

#include <cyg/libc/stdio/stream.hxx>// Cyg_StdioStream

// FUNCTIONS

// FIXME: should be reworked to read buffer at a time, and scan that

// for newlines, rather than reading byte at a time.

externC char *

gets( char *s )

{

    Cyg_StdioStream *real_stream = (Cyg_StdioStream *)stdin;

    Cyg_ErrNo err=ENOERR;

    cyg_uint8 c;

    cyg_uint8 *str=(cyg_uint8 *)s;

    int nch;

    CYG_CHECK_DATA_PTRC( s );

    CYG_CHECK_DATA_PTRC( real_stream );

    CYG_REPORT_FUNCTYPE( "returning string %08x");

    CYG_REPORT_FUNCARG1( "s=%08x", s );

    for (nch=1;; nch++) {

        err = real_stream->read_byte( &c );

        // if nothing to read, try again ONCE after refilling buffer

        if (EAGAIN == err) {

            err = real_stream->refill_read_buffer();

            if ( !err )

                err = real_stream->read_byte( &c );

            if (EAGAIN == err) {

                if (1 == nch) {   // indicates EOF at start

                    CYG_REPORT_RETVAL( NULL );

                    return NULL;

                } else

                    break; // EOF

            } // if

        } // if

        if ('\n' == c) // discard newlines

            break;

        *str++ = c;

    } // while

    *str = '\0'; // NULL terminate it

    if (err && EAGAIN != err) {

        real_stream->set_error( err );

        errno = err;

        CYG_REPORT_RETVAL( NULL );

        return NULL;

    } // if

    CYG_REPORT_RETVAL( s );

    return s;

} // gets()

// EOF gets.cxx