Test_ifstream_read

#include <windows.h>   // include important windows stuff
#include <windowsx.h>
#include <mmsystem.h>
#include <iostream> // include important C/C++ stuff
#include <conio.h>
#include <stdlib.h>
#include <malloc.h>
#include <memory.h>
#include <cstring>
#include <stdarg.h>
#include <stdio.h>
#include <math.h>
#include <io.h>
#include <fcntl.h>
#include <fstream>

using namespace std;



// DEFINES ////////////////////////////////////////////////

// defines for windows
#define WINDOW_CLASS_NAME L"WINCLASS1"

// default screen size
#define SCREEN_WIDTH    1024  // size of screen
#define SCREEN_HEIGHT   768
#define SCREEN_BPP      16   // bits per pixel

#define BITMAP_ID            0x4D42 // universal id for a bitmap
#define MAX_COLORS_PALETTE   256



// container structure for bitmaps .BMP file
typedef struct BITMAP_FILE_TAG
{
    BITMAPFILEHEADER bitmapfileheader;  // this contains the bitmapfile header
    BITMAPINFOHEADER bitmapinfoheader;  // this is all the info including the palette
    PALETTEENTRY     palette[256];      // we will store the palette here
    UCHAR            *buffer;           // this is a pointer to the data

} BITMAP_FILE, *BITMAP_FILE_PTR;

BITMAP_FILE bitmap;                // holds the bitmap



// FUNCTIONS ////////////////////////////////////////////////

void printError (char * errorName)
{
    // print error to log.txt
    ofstream errorFile = ofstream ("log.txt");
    if (errorFile.is_open ())
    {
        errorFile << errorName << endl; //"Error: OpenFile function failure. "
    }
    errorFile.close ();
}


int Flip_Bitmap(UCHAR *image, int bytes_per_line, int height)
{
    // this function is used to flip bottom-up .BMP images

    UCHAR *buffer; // used to perform the image processing
    int index;     // looping index

    // allocate the temporary buffer
    if (!(buffer = (UCHAR *) malloc (bytes_per_line * height)))
        return(0);

    // copy image to work area
    //memcpy(buffer, image, bytes_per_line * height);
    memcpy_s (buffer, bytes_per_line * height, image, bytes_per_line * height);

    // flip vertically
    for (index = 0; index < height; index++)
        memcpy(&image[((height - 1) - index) * bytes_per_line], &buffer[index * bytes_per_line], bytes_per_line);

    // release the memory
    free(buffer);

    // return success
    return(1);

} // end Flip_Bitmap

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


int Load_Bitmap_File(BITMAP_FILE_PTR bitmap, char *filename)
{
    int file_handle = 0;        // the file handle
    int index;                  // looping index
    UCHAR *temp_buffer = NULL; // used to convert 24 bit images to 16 bit
    streampos pos_cur;

    ifstream bitmapFile = ifstream ();
    bitmapFile.open (filename, ifstream::in);
    if (! bitmapFile.is_open ())
    {
        // print error to log.txt
        ofstream errorFile = ofstream ("log.txt");
        if (! errorFile.is_open ())
        {
            errorFile << "Error: OpenFile function failure. " << endl;
        }
        errorFile.close ();

        // abort
        return(0);
    }


    // load the bitmap file header:
    //_lread(file_handle, &(bitmap->bitmapfileheader), sizeof(BITMAPFILEHEADER));
    bitmapFile.read ((char *) &(bitmap->bitmapfileheader), sizeof (BITMAPFILEHEADER));

    // test if this is a bitmap file
    if (bitmap->bitmapfileheader.bfType != BITMAP_ID)
    {
        // close the file
        //_lclose(file_handle);
        bitmapFile.close ();

        printError ("error: wrong bitmap type");
        cout << "error: wrong bitmap type" << endl;

        // return error
        return(0);
    } // end if

    // now we know this is a bitmap, so read in all the sections.


    // now the bitmap infoheader:

    //_lread(file_handle, &bitmap->bitmapinfoheader, sizeof(BITMAPINFOHEADER));
    bitmapFile.seekg (sizeof (BITMAPFILEHEADER), ios::beg);
    pos_cur = bitmapFile.tellg (); // save current stream position
    bitmapFile.read ((char *) &(bitmap->bitmapinfoheader), sizeof (BITMAPINFOHEADER));

    //cout << bitmap->bitmapinfoheader.biBitCount << endl;

    // now load the color palette if there is one
    if (bitmap->bitmapinfoheader.biBitCount == 8)
    {
        //_lread(file_handle, &bitmap->palette, MAX_COLORS_PALETTE * sizeof(PALETTEENTRY));
        // not tested:
        bitmapFile.read ((char *) &(bitmap->palette), MAX_COLORS_PALETTE * sizeof(PALETTEENTRY));

        // now set all the flags in the palette correctly and fix the reversed
        // BGR RGBQUAD data format
        for (index = 0; index < MAX_COLORS_PALETTE; index++)
        {
            // reverse the red and green fields
            int temp_color                = bitmap->palette[index].peRed;
            bitmap->palette[index].peRed  = bitmap->palette[index].peBlue;
            bitmap->palette[index].peBlue = temp_color;

            // always set the flags word to this
            bitmap->palette[index].peFlags = PC_NOCOLLAPSE;
        } // end for index

    } // end if


    // finally the image data itself:
    //_lseek(file_handle, -((int) (bitmap->bitmapinfoheader.biSizeImage)), SEEK_END);
    bitmapFile.seekg (-((int) bitmap->bitmapinfoheader.biSizeImage), ios::end);
    //bitmapFile.seekg (sizeof (BITMAPINFOHEADER) + sizeof (BITMAPFILEHEADER) + MAX_COLORS_PALETTE * sizeof(PALETTEENTRY), ios::beg);

    // now read in the image, if the image is 8 or 16 bit then simply read it
    // but if its 24 bit then read it into a temporary area and then convert
    // it to a 16 bit image

    if (bitmap->bitmapinfoheader.biBitCount == 8  ||
         bitmap->bitmapinfoheader.biBitCount == 16 ||
         bitmap->bitmapinfoheader.biBitCount == 24)
    {
        // delete the last image if there was one
        if (bitmap->buffer)
            free(bitmap->buffer);

        // allocate the memory for the image
        if (!(bitmap->buffer = (UCHAR *) malloc (bitmap->bitmapinfoheader.biSizeImage)))
        {
            // close the file
            //_lclose(file_handle);
            bitmapFile.close ();

            // return error
            return(0);
        } // end if

        // now read it in
        //_lread(file_handle, bitmap->buffer, bitmap->bitmapinfoheader.biSizeImage);
        bitmapFile.read ((char *) (bitmap->buffer), bitmap->bitmapinfoheader.biSizeImage);

    } // end if
    else
    {
        // serious problem
        return(0);

    } // end else


    // close the file
    //_lclose(file_handle);
    bitmapFile.close ();

    // flip the bitmap
    Flip_Bitmap(bitmap->buffer,
                    bitmap->bitmapinfoheader.biWidth * (bitmap->bitmapinfoheader.biBitCount / 8),
                    bitmap->bitmapinfoheader.biHeight);

    // return success
    return(1);

} // end Load_Bitmap_File

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




int main (int argc, char * argv[])
{
    if (Load_Bitmap_File (&bitmap, "bitmap24.bmp") != 1)
    {
        cout << "error: picture opening failure" << endl;
    }

    cin.get();
    return 0;
}