console.c

一个开源著名的TDE编辑器源代码

        les     di, screen_ptr
        mov     ah, BYTE PTR attr
        mov     al, BYTE PTR c
        jmp     short done
   }
repeater:
   ASSEMBLE {
        mov     es:[di], ax
        add     di, bx
   }
done:
   ASSEMBLE {
        dec     cx                      /* is count more than zero? */
        jns     repeater

        pop     di
   }
}


/*
 * Name:    s_output
 * Purpose: To output a string
 * Date:    June 5, 1991
 * Passed:  s:     string to output
 *          line:  line to display
 *          col:   column to begin display
 *          attr:  color to display string
 * Notes:   This function is used to output most strings not part of file text.
 *
 * jmh 991023:  Possibly output an extra space before and after.
 * jmh 991027:  don't bother testing (s == NULL) or (*s == '\n').
 */
void s_output( const char *s, int line, int col, int attr )
{
char *screen_ptr = SCREEN_PTR( line, col );
int  max_col = g_display.ncols;
int  space = g_display.output_space;

   ASSEMBLE {
        push    ds                      /* save ds on stack */
        push    di                      /* save di on stack */
        push    si                      /* save si on stack */

        les     di, screen_ptr          /* load SEGMENT+OFFSET of screen ptr */
        lds     si, s                   /* load segment+offset of string ptr */
        mov     dx, WORD PTR col        /* put cols in dx */
        mov     cx, WORD PTR max_col    /* keep max_col in cx */
        mov     ah, BYTE PTR attr       /* keep attribute in ah */
        cmp     BYTE PTR space, 0       /* outputting a space? */
        je      begin                   /* no, skip it */
        test    dx, dx                  /* already on left edge? */
        je      begin                   /* yep, skip it */
        mov     al, ' '
        mov     es:[di-2], ax
   }
begin:
   ASSEMBLE {
        sub     cx, dx          /* max_col -= col */
        jle     getout
   }
top:

   ASSEMBLE {
        lodsb                   /* get next char in string - put in al */
        test    al, al          /* is it '\0' */
        jz      end             /* yes, end of string */
        stosw                   /* else show attr + char on screen (ah + al) */
        loop    SHORT top       /* get another character */
   }
end:

   ASSEMBLE {
        cmp     BYTE PTR space, 0
        je      getout
        jcxz    getout
        mov     al, ' '
        stosw
   }
getout:

   ASSEMBLE {
        pop     si              /* get back si */
        pop     di              /* get back di */
        pop     ds              /* get back ds */
   }
}


/*
 * Name:    hlight_line
 * Date:    July 21, 1991
 * Passed:  x:     column to begin hi lite
 *          y:     line to begin hi lite
 *          lgth:  number of characters to hi lite
 *          attr:  attribute color
 * Notes:   The attribute byte is the hi byte.
 */
void hlight_line( int x, int y, int lgth, int attr )
{
char *screen_ptr = SCREEN_PTR( y, x );

   ASSEMBLE {
        push    di              /* save di */

        mov     cx, lgth        /* number of characters to change color */
        les     di, screen_ptr  /* get destination - video memory */
        mov     al, BYTE PTR attr       /* attribute */
   }
lite_len:

   ASSEMBLE {
        inc     di              /* skip over character to attribute */
        stosb                   /* store a BYTE */
        loop    lite_len        /* change next attribute */

        pop     di              /* restore di */
   }
}


/*
 * Name:    cls
 * Purpose: clear screen
 * Date:    June 5, 1991
 * Notes:   Call the video BIOS routine to clear the screen.
 */
void cls( void )
{
int  line;
unsigned char column;
unsigned char attr;

   line = g_display.nlines - 1;
   column = (unsigned char)(g_display.ncols - 1);
   attr   = (unsigned char)Color( Text );

   ASSEMBLE {
        xor     cx, cx                  /* starting row in ch = 0 */
                                        /* starting column in cl = 0 */
        mov     ax, WORD PTR line       /* get ending row */
        mov     dh, al                  /* put it in dh */
        mov     dl, Byte Ptr column     /* ending column in dl = 79 */
        mov     bh, Byte Ptr attr       /* attribute in bh (jmh 990414) */
        mov     al, cl                  /* get number of lines */
        mov     ah, 6                   /* get function number */
        push    bp                      /* some BIOS versions wipe out bp */
        int     VIDEO_INT
        pop     bp
   }
}


/*
 * Name:    set_cursor_size
 * Purpose: To set cursor size according to insert mode.
 * Date:    June 5, 1991
 * Passed:  csize:  desired cursor size
 * Notes:   use the global display structures to set the cursor size
 */
void set_cursor_size( int csize )
{
   ASSEMBLE {
        mov     ah, 1                   /* function 1 - set cursor size */
        mov     cx, WORD PTR csize      /* get cursor size ch:cl == top:bot */
        push    bp
        int     VIDEO_INT               /* video interrupt = 10h */
        pop     bp
   }
}


/*
 * Name:    set_overscan_color
 * Purpose: To set overscan color
 * Date:    April 1, 1993
 * Passed:  color:  overscan color
 * Notes:   before setting the overscan color, the old overscan color
 *           needs to be saved so it can be restored.
 */
void set_overscan_color( int color )
{
   ASSEMBLE {
        mov     ah, 0x0b                /* function 0x0b */
        mov     bl, BYTE PTR color      /* get new overscan color */
        xor     bh, bh
        push    bp
        int     VIDEO_INT               /* video interrupt = 10h */
        pop     bp
   }
}


/*
 * Name:    save_screen_line
 * Purpose: To save the characters and attributes of a line on screen.
 * Date:    June 5, 1991
 * Passed:  col:    desired column, usually always zero
 *          line:   line on screen to save (0 up to max)
 *          screen_buffer:  buffer for screen contents, must be >= 160 chars
 * Notes:   Save the contents of the line on screen where prompt is
 *           to be displayed
 * jmh 991028: may as well write it in assembly.
 */
void save_screen_line( int col, int line, Char *screen_buffer )
{
char *p = SCREEN_PTR( line, col );
int  max_cols = g_display.ncols;

   ASSEMBLE {
        push    ds
        push    si
        push    di

        les     di, screen_buffer
        lds     si, p
        mov     cx, max_cols
        rep     movsw

        pop     di
        pop     si
        pop     ds
   }
}


/*
 * Name:    restore_screen_line
 * Purpose: To restore the characters and attributes of a line on screen.
 * Date:    June 5, 1991
 * Passed:  col:    usually always zero
 *          line:   line to restore (0 up to max)
 *          screen_buffer:  buffer for screen contents, must be >= 160 chars
 * Notes:   Restore the contents of the line on screen where the prompt
 *           was displayed
 * jmh 991028: may as well write it in assembly.
 */
void restore_screen_line( int col, int line, Char *screen_buffer )
{
char *p = SCREEN_PTR( line, col );
int  max_cols = g_display.ncols;

   ASSEMBLE {
        push    ds
        push    si
        push    di

        les     di, p
        lds     si, screen_buffer
        mov     cx, max_cols
        rep     movsw

        pop     di
        pop     si
        pop     ds
   }
}


/*
 * Name:    save_area
 * Purpose: save text and attribute
 * Date:    November 13, 1993
 * Passed:  buffer: storage for text and attribute
 *          wid: width to save
 *          len: length to save
 *          row: starting row of save
 *          col: starting column of save
 *
 * jmh 991022:  Rewrote in assembly.
 *              I should point out that the buffer should be (at least)
 *                (wid + 4) * (len + 1) * sizeof(Char) bytes.
 */
void save_area( Char *buffer, int wid, int len, int row, int col )
{
char *pointer;
int  cols = g_display.ncols;

   adjust_area( &wid, &len, &row, &col, NULL );

   pointer = SCREEN_PTR( row, col );

   ASSEMBLE {
        push    ds
        push    si
        push    di

        lds     si, pointer
        les     di, buffer
        mov     bx, cols                /* BX = (cols - wid) * 2 */
        sub     bx, wid                 /* It is used to point to */
        shl     bx, 1                   /*  the next screen row */
        mov     ax, len
   }
   line_loop:

   ASSEMBLE {
        mov     cx, wid
        rep     movsw                   /* buffer = screen */
        add     si, bx                  /* next row */
        dec     ax                      /* any more? */
        jnz     line_loop               /* yep (assumes len > 0) */

        pop     di
        pop     si
        pop     ds
   }
}


/*
 * Name:    restore_area
 * Purpose: restore text and attribute
 * Date:    November 13, 1993
 * Passed:  buffer: storage for text and attribute
 *          wid: width to restore
 *          len: length to restore
 *          row: starting row for restore
 *          col: starting column for restore
 *
 * jmh 991022:  Rewrote in assembly.
 *              I should point out that these parameters should be identical
 *                to those used in the corresponding save_area().
 */
void restore_area( Char *buffer, int wid, int len, int row, int col )
{
char *pointer;
int  cols = g_display.ncols;

   adjust_area( &wid, &len, &row, &col, NULL );

   pointer = SCREEN_PTR( row, col );

   ASSEMBLE {
        push    ds
        push    si
        push    di

        les     di, pointer
        lds     si, buffer
        mov     bx, cols                /* BX = (cols - wid) * 2 */
        sub     bx, wid                 /* It is used to point to */
        shl     bx, 1                   /*  the next screen row */
        mov     ax, len
   }
   line_loop:

   ASSEMBLE {
        mov     cx, wid
        rep     movsw                   /* screen = buffer */
        add     di, bx                  /* next row */
        dec     ax                      /* any more? */
        jnz     line_loop               /* yep (assumes len > 0) */

        pop     di
        pop     si
        pop     ds
   }
}


/*
 * Name:    shadow_area
 * Purpose: draw a shadow around an area
 * Author:  Jason Hood
 * Date:    October 20, 1999
 * Passed:  wid: width of area
 *          len: length of area
 *          row: starting row of area
 *          col: starting column of area
 * Notes:   the characters being shadowed are not saved.
 *          Use attribute 8 (dark grey on black) as the shadow.
 */
void shadow_area( int wid, int len, int row, int col )
{
char *pointer;
int w;
int cols = g_display.ncols * 2;
int alen;

   if (g_display.shadow) {
      alen = len;
      adjust_area( &wid, &len, &row, &col, &w );

      if (w > 0) {
         pointer = display_address + (row + 1) * cols + (col + wid) * 2;
      ASSEMBLE {
        push    di

        les     di, pointer
        mov     dx, cols
        mov     ax, w
        shl     ax, 1
        add     dx, ax          /* dx is offset to next line */
        mov     al, 8           /* attribute */
        mov     cx, len
        dec     cx              /* skip the first line */
        std                     /* going backwards */
      }
   shadow_line:

      ASSEMBLE {
        mov     bx, w           /* number of characters to shadow */
      }
   shadow_char:

      ASSEMBLE {
        dec     di              /* point to attribute */
        stosb                   /* store a BYTE */
        dec     bx
        jnz     shadow_char
        add     di, dx          /* next line */
        loop    shadow_line

        cld
        pop     di
       }
      }
      if (alen < len) {
         col += g_display.shadow_width;
         wid -= g_display.shadow_width + w;
         /* hlight_line( col, row + len - 1, wid, 8 ); */
         pointer = display_address + (row + len - 1) * cols + col * 2;
      ASSEMBLE {
        push    di

        mov     cx, wid
        les     di, pointer
        mov     al, 8
      }
   shadow_len:

      ASSEMBLE {
        inc     di              /* skip over character to attribute */
        stosb                   /* store a BYTE */
        loop    shadow_len      /* change next attribute */

        pop     di
       }
      }
   }
}