strget.c

该程序是C语言编写的

/****************************************************************/
/* Getstr() routines of the PCcurses package			*/
/*								*/
/****************************************************************/
/* This version of curses is based on ncurses, a curses version	*/
/* originally written by Pavel Curtis at Cornell University.	*/
/* I have made substantial changes to make it run on IBM PC's,	*/
/* and therefore consider myself free to make it public domain.	*/
/*				Bjorn Larsson ([e-mail])	*/
/****************************************************************/
/* 1.4:  Use of short wherever possible. Portability		*/
/*	 improvements, echo bug, fix for signed character	*/
/*	 (for 8-bit ASCII):				900114	*/
/* 1.3:	 MSC -W3, Turbo'C' -w -w-pro checkes:		881005	*/
/* 1.2:	 Max limits of by 1. Block nest error in function	*/
/*	 backchar(). Fixed thanks to S. Creps:		881002	*/
/* 1.0:	 Release:					870515	*/
/****************************************************************/

#include <curses.h>
#include <curspriv.h>

static	char	*backchar();

char _curses_strget_rcsid[] = "@(#)strget.c     v.1.4  - 900114";

static	bool	 oldecho;
static	bool	 oldcbreak;
static  bool     oldnodelay;
static	char	*strbeg;
static	WINDOW  *w;
static	short	 xbeg;

/****************************************************************/
/* Wgetstr(win,str) reads in a string (terminated by \n or \r)	*/
/* to the buffer pointed to by 'str', and displays the input	*/
/* in window 'win'. The user's erase and kill characters are	*/
/* active.							*/
/****************************************************************/

int wgetstr(win,str)
  WINDOW	*win; 
  char		*str;
  {
  w		  = win;
  strbeg	  = str;		/* keep start for backspacing */
  oldcbreak       = _cursvar.cbreak;	/* remember states */
  oldecho         = _cursvar.echo;
  oldnodelay      = w->_nodelay;
  _cursvar.echo   = FALSE;		/* we do echo ourselves */
  _cursvar.cbreak = TRUE;		/* no wait for chars */
  w->_nodelay   = FALSE;		/* don't return 'NOCHARS' */
  xbeg = w->_curx;			/* remember screen start x-position */

  wrefresh(w);				/* sets cursor at right place */
  while ((*str = (char) getch()) != '\n')
    {
    if (*str == '\r')
      break;
    if (*str == _DCCHAR)
      {
      if (str > strbeg)
	str = backchar(str);
      } /* if */
    else
      if (*str == _DLCHAR)
	while (str > strbeg)
	  str = backchar(str);
      else
	{
        if (oldecho)			/* check if echo */
          {
	  waddch(w,*str++);
	  wrefresh(w);
          }
	else
	  str++;
	} /* else */
      } /* while */

  *str = '\0';
  _cursvar.echo   = oldecho;
  _cursvar.cbreak = oldcbreak;
  win->_nodelay   = oldnodelay;
  return(OK);
  } /* wgetstr */

/****************************************************************/
/* Getstr(str) reads in a string (terminated by \n or \r) to	*/
/* the buffer pointed to by 'str', and displays the input in	*/
/* stdscr. The user's erase and kill characters are active.	*/
/****************************************************************/

int getstr(str)
  char *str;
  {
  return(wgetstr(stdscr,str));
  } /* getstr */

/****************************************************************/
/* Mvgetstr(y,x,str) moves the stdscr cursor to a new position,	*/
/* then reads in a string (terminated by \n or \r) to the buf-	*/
/* fer pointed to by 'str', and displays the input in stdscr.	*/
/* The user's erase and kill characters are active.		*/
/****************************************************************/

int mvgetstr(y,x,str)
  int y;
  int x;
  char *str;
  {
  if (wmove(stdscr,y,x) == ERR)
    return(ERR);
  return(wgetstr(stdscr,str));
  } /* mvgetstr */

/****************************************************************/
/* Mvwgetstr(win,y,x,str) moves the 'win' cursor to a new	*/
/* position, then reads in a string (terminated by \n or \r)	*/
/* to the buffer pointed to by 'str', and displays the input in	*/
/* stdscr. The user's erase and kill characters are active.	*/
/****************************************************************/

int mvwgetstr(win,y,x,str)
  WINDOW *win;
  int	  y;
  int	  x;
  char	 *str;
  {
  if (wmove(win,y,x) == ERR)
    return(ERR);
  return(wgetstr(win,str));
  } /* mvwgetstr */

/****************************************************************/
/* Backchar() does a character delete with screen erase, even	*/
/* up to previous lines. It will not back-scroll if the begi-	*/
/* ning of the string has scrolled off the window. Steps back	*/
/* pointer 's', and returns the new value.			*/
/****************************************************************/

static char *backchar(s)
  char	  *s;
  {
  static short nbs;
  static short x;
  static char *p;
  static short ts;

  x =  xbeg;
  ts =  w->_tabsize;

  s--;						/* step back string */
  nbs = 1;					/* step at least one pos */
  if (((*s & 0xe0) == 0) || (*s == 0x7f))	/* ctrl-char has size 2 */
    nbs++;
  if (*s == '\t')				/* tabs are very special */
    {
    for (p = strbeg; p < s ;p++)		/* find x-pos of last char */
      {
      if (*p == '\t')				/* go to next tab */
	x = ((x/ts)+1) * ts;
      else
	{
	if (((*p & 0xe0) == 0) || (*p == 0x7f))	/* control character */
	  x += 2;
	else					/* normal char */
	  x++;
	} /* else */
      if (x >= w->_maxx)			/* go to next line? */
	x = 0;
      } /* for */
    if (!(w->_curx))				/* if step-over newline */
      nbs = w->_maxx - x;
    else					/* in-line tab */
      nbs = w->_curx - x;			/* positions to erase */
    } /* if */

  if ((int) oldecho)				/* check if echo */
    {
    while(nbs--)				/* do so many */
      {
      if (w->_curx > 0)				/* if not at line beginning */
        waddstr(w,"\b \b");
      else
        if (w->_cury)				/* if not on top line */
	  {
  	  mvwaddch(w,w->_cury-1,w->_maxx -1,' ');/* put space at line end */
	  wmove(w,w->_cury-1,w->_maxx - 1);	/* and go there again */
  	  } /* else */
      } /* while */
    wrefresh(w);				/* redraw screen */
    }
  *(s+1) = '\0';				/* make string terminated */
  return(s);
  } /* backchar */