RWPAL.C

/****************************************************************************/ 
    /*                                                                          */ 
    /*                 Copyright (C) 1987-1996 Microsoft Corp.                */ 
    /*                           All Rights Reserved                            */ 
    /*                                                                          */ 
    /****************************************************************************/ 
    /****************************** Module Header ******************************* 
    * Module Name: rwpal.c 
    * 
    * Routines for reading and writing color palette files. 
    * 
    * History: 
    * 
    ****************************************************************************/ 
     
    #include "imagedit.h" 
     
    #include <stdio.h> 
    #include <fcntl.h> 
    #include <io.h> 
    #include <sys\types.h>                      // For fstat() types. 
    #include <sys\stat.h>                       // For fstat() function. 
     
     
    /* 
     * The color palette is saved in a .PAL file.  This file consists 
     * of a header followed by the colors. 
     * 
     * The header has the following format: 
     * 
     * struct { 
     *     CHAR tag;                // Always 'C'. 
     *     WORD colors;             // Number of colors.  Always COLORSMAX. 
     *     CHAR reserved[47];       // Reserved bytes. 
     * } 
     * 
     * Immediately following this is RGB quads for each of the colors in 
     * the palette. 
     */ 
     
     
    /* 
     * Size in bytes of the header of a color palette file. 
     */ 
    #define CBCOLORHDR          (sizeof(CHAR) + sizeof(WORD) + 47) 
     
    /* 
     * Size in bytes of the color information in the color file. 
     */ 
    #define CBCOLORINFO         (sizeof(DWORD) * COLORSMAX) 
     
    /* 
     * Size in bytes of a color palette file.  This includes the 
     * size of the header and room for all the colors. 
     */ 
    #define CBCOLORFILE         (CBCOLORHDR + CBCOLORINFO) 
     
     
     
    /************************************************************************ 
    * LoadColorFile 
    * 
    * 
    * 
    * Arguments: 
    * 
    * History: 
    * 
    ************************************************************************/ 
     
    VOID LoadColorFile(VOID) 
    { 
        HFILE hf; 
        OFSTRUCT OfStruct; 
        struct stat FileStatus; 
        DWORD argb[COLORSMAX]; 
        UINT cbRead; 
        INT i; 
        CHAR tag; 
        CHAR szFileName[CCHMAXPATH]; 
     
        *szFileName = '\0'; 
        if (!OpenDlg(szFileName, FT_PALETTE)) 
            return; 
     
  if ((hf = (HFILE)OpenFile(szFileName, (LPOFSTRUCT)&OfStruct, OF_READ)) 
                == (HFILE)-1) { 
            Message(MSG_CANTOPEN, szFileName); 
            return; 
        } 
     
        fstat((INT)_open_osfhandle((long)(hf), (int)(O_RDONLY)), &FileStatus); 
     
        if (FileStatus.st_size != CBCOLORFILE) { 
            Message(MSG_BADPALFILE, szFileName); 
            goto Error1; 
        } 
     
        if ((cbRead = _lread((HFILE)hf, &tag, 1)) == -1 || cbRead != 1) { 
            Message(MSG_READERROR, szFileName); 
            goto Error1; 
        } 
     
        if (tag != 'C') { 
            Message(MSG_BADPALFILE, szFileName); 
            goto Error1; 
        } 
     
        SetFilePointer((HANDLE)hf, CBCOLORHDR, NULL, (DWORD)0); 
        if ((cbRead = _lread((HFILE)hf, (LPSTR)argb, CBCOLORINFO)) == -1 || 
                cbRead != CBCOLORINFO) { 
            Message(MSG_READERROR, szFileName); 
            goto Error1; 
        } 
     
        for (i = 0; i < COLORSMAX; i++) 
            gargbColor[i] = argb[i]; 
     
        SetColorPalette(16, giType, TRUE); 
     
    Error1: 
        _lclose((HFILE)hf); 
    } 
     
     
     
    /************************************************************************ 
    * SaveColorFile 
    * 
    * 
    * 
    * Arguments: 
    * 
    * History: 
    * 
    ************************************************************************/ 
     
    VOID SaveColorFile(VOID) 
    { 
        INT i; 
        HFILE hf; 
        OFSTRUCT OfStruct; 
        CHAR reserved[47]; 
        WORD wColors = COLORSMAX; 
        CHAR tag = 'C'; 
        CHAR szFileName[CCHMAXPATH]; 
     
        *szFileName = '\0'; 
        if (!SaveAsDlg(szFileName, FT_PALETTE)) 
            return; 
     
        if ((hf = (HFILE)OpenFile(szFileName, &OfStruct, 
                OF_CREATE | OF_WRITE)) == (HFILE)-1) { 
            Message(MSG_CANTCREATE, szFileName); 
            return; 
        } 
     
        for (i = 0; i < sizeof(reserved); i++) 
            reserved[i] = 0; 
     
        if (_lwrite((HFILE)hf, (LPSTR)&tag, sizeof(tag)) != sizeof(tag) || 
                _lwrite((HFILE)hf, (LPSTR)&wColors, sizeof(wColors)) != 
                sizeof(wColors) || 
                _lwrite((HFILE)hf, (LPSTR)reserved, sizeof(reserved)) != 
                sizeof(reserved) || 
                _lwrite((HFILE)hf, (LPSTR)gargbColor, CBCOLORINFO) != CBCOLORINFO) { 
            Message(MSG_WRITEERROR, szFileName); 
        } 
     
        _lclose((HFILE)hf); 
    }