stdio.c

这是在linux下gnu环境中进行norflash测试的代码

/* ----------------------------------------------------------------------------
 *         ATMEL Microcontroller Software Support 
 * ----------------------------------------------------------------------------
 * Copyright (c) 2008, Atmel Corporation
 *
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * - Redistributions of source code must retain the above copyright notice,
 * this list of conditions and the disclaimer below.
 *
 * Atmel's name may not be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * DISCLAIMER: THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE
 * DISCLAIMED. IN NO EVENT SHALL ATMEL BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
 * OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
 * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 * ----------------------------------------------------------------------------
 */

//------------------------------------------------------------------------------
/// \unit
///
/// !Purpose
///
/// Implementation of several stdio.h methods, such as printf(), sprintf() and
/// so on. This reduces the memory footprint of the binary when using those
/// methods, compared to the libc implementation.
///
/// !Usage
///
/// Adds stdio.c to the list of file to compile for the project. This will
/// automatically replace libc methods by the custom ones.
//------------------------------------------------------------------------------

//------------------------------------------------------------------------------
//         Headers
//------------------------------------------------------------------------------

#include <stdio.h>
#include <stdarg.h>

//------------------------------------------------------------------------------
//         Local Definitions
//------------------------------------------------------------------------------

// Maximum string size allowed (in bytes).
#define MAX_STRING_SIZE         100

//------------------------------------------------------------------------------
//         Global Variables
//------------------------------------------------------------------------------

// Required for proper compilation.
struct _reent r = {0, (FILE *) 0, (FILE *) 1, (FILE *) 0};
struct _reent *_impure_ptr = &r;

//------------------------------------------------------------------------------
//         Local Functions
//------------------------------------------------------------------------------

//------------------------------------------------------------------------------
// Writes a character inside the given string. Returns 1.
// \param pStr  Storage string.
// \param c  Character to write.
//------------------------------------------------------------------------------
signed int PutChar(char *pStr, char c)
{
    *pStr = c;
    return 1;
}

//------------------------------------------------------------------------------
// Writes a string inside the given string.
// Returns the size of the written
// string.
// \param pStr  Storage string.
// \param pSource  Source string.
//------------------------------------------------------------------------------
signed int PutString(char *pStr, const char *pSource)
{
    signed int num = 0;

    while (*pSource != 0) {

        *pStr++ = *pSource++;
        num++;
    }

    return num;
}

//------------------------------------------------------------------------------
// Writes an unsigned int inside the given string, using the provided fill &
// width parameters.
// Returns the size in characters of the written integer.
// \param pStr  Storage string.
// \param fill  Fill character.
// \param width  Minimum integer width.
// \param value  Integer value.
//------------------------------------------------------------------------------
signed int PutUnsignedInt(
    char *pStr,
    char fill,
    signed int width,
    unsigned int value)
{
    signed int num = 0;

    // Take current digit into account when calculating width
    width--;

    // Recursively write upper digits
    if ((value / 10) > 0) {

        num = PutUnsignedInt(pStr, fill, width, value / 10);
        pStr += num;
    }
    // Write filler characters
    else {

        while (width > 0) {

            PutChar(pStr, fill);
            pStr++;
            num++;
            width--;
        }
    }

    // Write lower digit
    num += PutChar(pStr, (value % 10) + '0');

    return num;
}

//------------------------------------------------------------------------------
// Writes a signed int inside the given string, using the provided fill & width
// parameters.
// Returns the size of the written integer.
// \param pStr  Storage string.
// \param fill  Fill character.
// \param width  Minimum integer width.
// \param value  Signed integer value.
//------------------------------------------------------------------------------
signed int PutSignedInt(
    char *pStr,
    char fill,
    signed int width,
    signed int value)
{
    signed int num = 0;
    unsigned int absolute;

    // Compute absolute value
    if (value < 0) {

        absolute = -value;
    }
    else {

        absolute = value;
    }

    // Take current digit into account when calculating width
    width--;

    // Recursively write upper digits
    if ((absolute / 10) > 0) {

        if (value < 0) {
        
            num = PutSignedInt(pStr, fill, width, -(absolute / 10));
        }
        else {

            num = PutSignedInt(pStr, fill, width, absolute / 10);
        }
        pStr += num;
    }
    else {

        // Reserve space for sign
        if (value < 0) {

            width--;
        }

        // Write filler characters
        while (width > 0) {

            PutChar(pStr, fill);
            pStr++;
            num++;
            width--;
        }

        // Write sign
        if (value < 0) {

            num += PutChar(pStr, '-');
            pStr++;
        }
    }

    // Write lower digit
    num += PutChar(pStr, (absolute % 10) + '0');

    return num;
}

//------------------------------------------------------------------------------
// Writes an hexadecimal value into a string, using the given fill, width &
// capital parameters.
// Returns the number of char written.
// \param pStr  Storage string.
// \param fill  Fill character.
// \param width  Minimum integer width.
// \param maj  Indicates if the letters must be printed in lower- or upper-case.
// \param value  Hexadecimal value.
//------------------------------------------------------------------------------
signed int PutHexa(
    char *pStr,
    char fill,
    signed int width,
    unsigned char maj,
    unsigned int value)
{
    signed int num = 0;

    // Decrement width
    width--;

    // Recursively output upper digits
    if ((value >> 4) > 0) {

        num += PutHexa(pStr, fill, width, maj, value >> 4);
        pStr += num;
    }
    // Write filler chars
    else {

        while (width > 0) {

            PutChar(pStr, fill);
            pStr++;
            num++;
            width--;