wtitle.c

详细介绍了一篇关于pci开发的接口芯片

/*  CXL - Copyright (c) 1987-1989 by Mike Smedley - All Rights Reserved  */
/*  WTITLE.C    - gives active window a title  */

#include <stdlib.h>
#include <string.h>
#include "cxldef.h"
#include "cxlstr.h"
#include "cxlvid.h"
#include "cxlwin.h"

int wtitle(char *str,int tpos,int tattr)
{
    int left,right,start,len,width,offs;
    char *p;

    /* check for active window */
    if(!_winfo.total) return(_winfo.errno=W_NOACTIVE);

    /* check for monochrome adapter, adjust title attribute */
    tattr=mapattr(tattr);

    /* redraw box if deleting or moving title */
    if(str==NULL||_winfo.active->title!=NULL) {
        if(_winfo.active->border)
            box_(_winfo.active->srow,_winfo.active->scol,_winfo.active->erow,
                 _winfo.active->ecol,_winfo.active->btype,
                 _winfo.active->battr);
    }

    /* if not deleting the title, calculate position and display it */
    if(str!=NULL) {
        left=_winfo.active->scol+1;
        right=_winfo.active->ecol-1;
        width=right-left+1;
        len=strlen(str);

        /* don't display title if window is borderless */
        if(_winfo.active->border) {

            switch(tpos) {
                case TLEFT:
                    start=(len>(width-3))?left:(left+1);
                    break;
                case TCENTER:
                    start=(len>(width-2))?left:(((width/2)+left)-(len/2));
                    break;
                default:        /* default is TRIGHT */
                    offs=width-len;
                    if(offs>2) offs--;
                    start=(len>width)?left:(left+offs);
            }

            /* allocate space for window title string, and copy it there */
            if((p=malloc(((width>len)?width:len)+1))==NULL)
                return(_winfo.errno=W_ALLOCERR);
            strcpy(p,str);
            *(p+width)='\0';

            /* display title string */
            prints(_winfo.active->srow,start,tattr,p);

            /* free allocated space */
            free(p);
        }
    }

    /* update window's record */
    _winfo.active->title=str;
    _winfo.active->tpos=tpos;
    _winfo.active->tattr=tattr;

    /* return normally */
    return(_winfo.errno=W_NOERROR);
}