main.c

源码,标准c++用力

		 */
#ifdef DEBUGGING
		fprintf(stderr, "Opened!\n");
#endif
		(void) devindex++;
		return 0;
	    }
#ifdef DEBUGGING
		fprintf(stderr, "Didn't open!\n");
#endif
	    devindex++;
	}
	devindex = 0;
	(void) letter++;
    }
#endif /* CRAY else */
    /*
     * We were unable to allocate a pty master!  Return an error
     * condition and let our caller terminate cleanly.
     */
    return 1;
}

get_terminal ()
/* 
 * sets up X and initializes the terminal structure except for term.buf.fildes.
 */
{
	register TScreen *screen = &term->screen;
	
#ifdef DEBUGGING
	fprintf(stderr, "entered get_terminal\n");
#endif
	screen->arrow = make_colored_cursor (XC_left_ptr, 
					     screen->mousecolor,
					     screen->mousecolorback);
}

/*
 * The only difference in /etc/termcap between 4014 and 4015 is that 
 * the latter has support for switching character sets.  We support the
 * 4015 protocol, but ignore the character switches.  Therefore, we 
 * choose 4014 over 4015.
 *
 * Features of the 4014 over the 4012: larger (19") screen, 12-bit
 * graphics addressing (compatible with 4012 10-bit addressing),
 * special point plot mode, incremental plot mode (not implemented in
 * later Tektronix terminals), and 4 character sizes.
 * All of these are supported by xterm.
 */

static char *tekterm[] = {
	"tek4014",
	"tek4015",		/* 4014 with APL character set support */
	"tek4012",		/* 4010 with lower case */
	"tek4013",		/* 4012 with APL character set support */
	"tek4010",		/* small screen, upper-case only */
	"dumb",
	0
};

/* The VT102 is a VT100 with the Advanced Video Option included standard.
 * It also adds Escape sequences for insert/delete character/line.
 * The VT220 adds 8-bit character sets, selective erase.
 * The VT320 adds a 25th status line, terminal state interrogation.
 * The VT420 has up to 48 lines on the screen.
 */

static char *vtterm[] = {
#ifdef USE_X11TERM
	"x11term",		/* for people who want special term name */
#endif
	"color_xterm",
	"xterm",		/* the prefered name, should be fastest */
	"vt102",
	"vt100",
	"ansi",
	"dumb",
	0
};

/* ARGSUSED */
SIGNAL_T hungtty(i)
	int i;
{
#ifdef DEBUGGING
	fprintf(stderr, "entered hungtty\n");
#endif
	longjmp(env, 1);
	SIGNAL_RETURN;
}

#ifdef USE_HANDSHAKE
typedef enum {		/* c == child, p == parent                        */
	PTY_BAD,	/* c->p: can't open pty slave for some reason     */
	PTY_FATALERROR,	/* c->p: we had a fatal error with the pty        */
	PTY_GOOD,	/* c->p: we have a good pty, let's go on          */
	PTY_NEW,	/* p->c: here is a new pty slave, try this        */
	PTY_NOMORE,	/* p->c; no more pty's, terminate                 */
	UTMP_ADDED,	/* c->p: utmp entry has been added                */
	UTMP_TTYSLOT,	/* c->p: here is my ttyslot                       */
	PTY_EXEC	/* p->c: window has been mapped the first time    */
} status_t;

typedef struct {
	status_t status;
	int error;
	int fatal_error;
	int tty_slot;
	int rows;
	int cols;
	char buffer[1024];
} handshake_t;

/* HsSysError()
 *
 * This routine does the equivalent of a SysError but it handshakes
 * over the errno and error exit to the master process so that it can
 * display our error message and exit with our exit code so that the
 * user can see it.
 */

void
HsSysError(pf, error)
int pf;
int error;
{
	handshake_t handshake;
#ifdef DEBUGGING
	fprintf(stderr, "entered HsSysError\n");
#endif

	handshake.status = PTY_FATALERROR;
	handshake.error = errno;
	handshake.fatal_error = error;
	strcpy(handshake.buffer, ttydev);
	write(pf, (char *) &handshake, sizeof(handshake));
	exit(error);
}

static int pc_pipe[2];	/* this pipe is used for parent to child transfer */
static int cp_pipe[2];	/* this pipe is used for child to parent transfer */

void first_map_occurred ()
{
    handshake_t handshake;
    register TScreen *screen = &term->screen;

#ifdef DEBUGGING
	fprintf(stderr, "entered first_map_occurred\n");
#endif
    handshake.status = PTY_EXEC;
    handshake.rows = screen->max_row;
    handshake.cols = screen->max_col;
    write (pc_pipe[1], (char *) &handshake, sizeof(handshake));
    close (cp_pipe[0]);
    close (pc_pipe[1]);
    waiting_for_initial_map = False;
}
#else
/*
 * temporary hack to get xterm working on att ptys
 */
void first_map_occurred ()
{
    return;
}
#define HsSysError(a,b)
#endif /* USE_HANDSHAKE else !USE_HANDSHAKE */


spawn ()
/* 
 *  Inits pty and tty and forks a login process.
 *  Does not close fd Xsocket.
 *  If slave, the pty named in passedPty is already open for use
 */
{
	extern char *SysErrorMsg();
	register TScreen *screen = &term->screen;
	int Xsocket = ConnectionNumber(screen->display);
#ifdef USE_HANDSHAKE
	handshake_t handshake;
#else
	int fds[2];
#endif
	int tty = -1;
	int discipline;
	int done;
#ifdef USE_SYSV_TERMIO
	struct termio tio;
	struct termio dummy_tio;
#ifdef TIOCLSET
	unsigned lmode;
#endif	/* TIOCLSET */
#ifdef TIOCSLTC
	struct ltchars ltc;
#endif	/* TIOCSLTC */
	int one = 1;
	int zero = 0;
	int status;
#else	/* else not USE_SYSV_TERMIO */
	unsigned lmode;
	struct tchars tc;
	struct ltchars ltc;
	struct sgttyb sg;
#ifdef sony
	int jmode;
	struct jtchars jtc;
#endif /* sony */
#endif	/* USE_SYSV_TERMIO */

	char termcap [1024];
	char newtc [1024];
	char *ptr, *shname, *shname_minus;
	int i, no_dev_tty = FALSE;
#ifdef USE_SYSV_TERMIO
	char *dev_tty_name = (char *) 0;
	int fd;			/* for /etc/wtmp */
#endif	/* USE_SYSV_TERMIO */
	char **envnew;		/* new environment */
	int envsize;		/* elements in new environment */
	char buf[64];
	char *TermName = NULL;
	int ldisc = 0;
#ifdef sun
#ifdef TIOCSSIZE
	struct ttysize ts;
#endif	/* TIOCSSIZE */
#else	/* not sun */
#ifdef TIOCSWINSZ
	struct winsize ws;
#endif	/* TIOCSWINSZ */
#endif	/* sun */
	struct passwd *pw = NULL;
#ifdef UTMP
	struct utmp utmp;
#ifdef LASTLOG
	struct lastlog lastlog;
#endif	/* LASTLOG */
#endif	/* UTMP */

#ifdef DEBUGGING
	fprintf(stderr, "entered spawn()\n");
#endif
	screen->uid = getuid();
	screen->gid = getgid();

#ifdef SIGTTOU
	/* so that TIOCSWINSZ || TIOCSIZE doesn't block */
	signal(SIGTTOU,SIG_IGN);
#endif

	if (am_slave) {
		screen->respond = am_slave;
		ptydev[strlen(ptydev) - 2] = ttydev[strlen(ttydev) - 2] =
			passedPty[0];
		ptydev[strlen(ptydev) - 1] = ttydev[strlen(ttydev) - 1] =
			passedPty[1];

		setgid (screen->gid);
#ifdef GAPING_SECURITY_HOLE
	  if (resetuid)
#endif
		setuid (screen->uid);
	} else {
		Bool tty_got_hung = False;

 		/*
 		 * Sometimes /dev/tty hangs on open (as in the case of a pty
 		 * that has gone away).  Simply make up some reasonable
 		 * defaults.
 		 */
 		signal(SIGALRM, hungtty);
 		alarm(2);		/* alarm(1) might return too soon */
 		if (! setjmp(env)) {
 			tty = open ("/dev/tty", O_RDWR, 0);
 			alarm(0);
 		} else {
			tty_got_hung = True;
 			tty = -1;
 			errno = ENXIO;
 		}
 		signal(SIGALRM, SIG_DFL);
 
		/*
		 * Check results and ignore current control terminal if
		 * necessary.  ENXIO is what is normally returned if there is
		 * no controlling terminal, but some systems (e.g. SunOS 4.0)
		 * seem to return EIO.
		 */
 		if (tty < 0) {
			DBG("Problem with tty.")
			if (tty_got_hung || errno == ENXIO || errno == EIO ||
			    errno == ENOTTY) {
				no_dev_tty = TRUE;
#ifdef TIOCSLTC
				ltc = d_ltc;
#endif	/* TIOCSLTC */
#ifdef TIOCLSET
				lmode = d_lmode;
#endif	/* TIOCLSET */
#ifdef USE_SYSV_TERMIO
				tio = d_tio;
#else	/* not USE_SYSV_TERMIO */
				sg = d_sg;
				tc = d_tc;
				discipline = d_disipline;
#ifdef sony
				jmode = d_jmode;
				jtc = d_jtc;
#endif /* sony */
#endif	/* USE_SYSV_TERMIO */
			} else {
			    SysError(ERROR_OPDEVTTY);
			}
		} else {
			/* Get a copy of the current terminal's state,
			 * if we can.  Some systems (e.g., SVR4 and MacII)
			 * may not have a controlling terminal at this point
			 * if started directly from xdm or xinit,     
			 * in which case we just use the defaults as above.
			 */
#ifdef TIOCSLTC
			if(ioctl(tty, TIOCGLTC, &ltc) == -1)
				ltc = d_ltc;
#endif	/* TIOCSLTC */
#ifdef TIOCLSET
			if(ioctl(tty, TIOCLGET, &lmode) == -1)
				lmode = d_lmode;
#endif	/* TIOCLSET */
#ifdef USE_SYSV_TERMIO
		        if(ioctl(tty, TCGETA, &tio) == -1)
			        tio = d_tio;

#else	/* not USE_SYSV_TERMIO */
			if(ioctl(tty, TIOCGETP, (char *)&sg) == -1)
			        sg = d_sg;
			if(ioctl(tty, TIOCGETC, (char *)&tc) == -1)
			        tc = d_tc;
			if(ioctl(tty, TIOCGETD, (char *)&discipline) == -1)
			        discipline = d_disipline;
#ifdef sony
			if(ioctl(tty, TIOCKGET, (char *)&jmode) == -1)
			        jmode = d_jmode;
			if(ioctl(tty, TIOCKGETC, (char *)&jtc) == -1)
				jtc = d_jtc;
#endif /* sony */
#endif	/* USE_SYSV_TERMIO */
			close (tty);
			/* tty is no longer an open fd! */
			tty = -1;
		}

#ifdef 	PUCC_PTYD
		if(-1 == (screen->respond = openrpty(ttydev, ptydev,
				(resource.utmpInhibit ?  OPTY_NOP : OPTY_LOGIN),
				getuid(), XDisplayString(screen->display)))) {
#else /* not PUCC_PTYD */
		if (get_pty (&screen->respond)) {
#endif /* PUCC_PTYD */
			/*  no ptys! */
			(void) fprintf(stderr, "%s: no available ptys\n",
				       xterm_name);
			exit (ERROR_PTYS);
#ifdef PUCC_PTYD
		}
#else
		}			/* keep braces balanced for emacs */
#endif
#ifdef PUCC_PTYD
		  else {
			/*
			 *  set the fd of the master in a global var so
			 *  we can undo all this on exit
			 *
			 */
			Ptyfd = screen->respond;
		  }
#endif /* PUCC_PTYD */
	}

	/* avoid double MapWindow requests */
	XtSetMappedWhenManaged( screen->TekEmu ? XtParent(tekWidget) :
			        XtParent(term), False );
	wm_delete_window = XInternAtom(XtDisplay(toplevel), "WM_DELETE_WINDOW",
				       False);
	if (!screen->TekEmu)
	    VTInit();		/* realize now so know window size for tty driver */
#ifdef TIOCCONS
	if (Console) {
	    /*
	     * Inform any running xconsole program
	     * that we are going to steal the console.
	     */
	    XmuGetHostname (mit_console_name + MIT_CONSOLE_LEN, 255);
	    mit_console = XInternAtom(screen->display, mit_console_name, False);
	    /* the user told us to be the console, so we can use CurrentTime */
	    XtOwnSelection(screen->TekEmu ? XtParent(tekWidget) : XtParent(term),
			   mit_console, CurrentTime,
			   ConvertConsoleSelection, NULL, NULL);
	}
#endif
	if(screen->TekEmu) {
		envnew = tekterm;
		ptr = newtc;
	} else {
		envnew = vtterm;
		ptr = termcap;
	}
	TermName = NULL;
	if (resource.term_name) {
	    if (tgetent (ptr, resource.term_name) == 1) {
		TermName = resource.term_name;
		if (!screen->TekEmu)
		    resize (screen, TermName, termcap, newtc);
	    } else {
		fprintf (stderr, "%s:  invalid termcap entry \"%s\".\n",
			 ProgramName, resource.term_name);
	    }
	}
	if (!TermName) {
	    while (*envnew != NULL) {
		if(tgetent(ptr, *envnew) == 1) {
			TermName = *envnew;
			if(!screen->TekEmu)
			    resize(screen, TermName, termcap, newtc);
			break;
		}
		envnew++;
	    }
	    if (TermName == NULL) {
		fprintf (stderr, "%s:  unable to find usable termcap entry.\n",
			 ProgramName);
		Exit (1);
	    }
	}

#ifdef sun
#ifdef TIOCSSIZE
	/* tell tty how big window is */
	if(screen->TekEmu) {
		ts.ts_lines = 38;
		ts.ts_cols = 81;
	} else {
		ts.ts_lines = screen->max_row + 1;
		ts.ts_cols = screen->max_col + 1;
	}
#endif	/* TIOCSSIZE */
#else	/* not sun */
#ifdef TIOCSWINSZ
	/* tell tty how big window is */
	if(screen->TekEmu) {
		ws.ws_row = 38;
		ws.ws_col = 81;
		ws.ws_xpixel = TFullWidth(screen);
		ws.ws_ypixel = TFullHeight(screen);
	} else {
		ws.ws_row = screen->max_row + 1;
		ws.ws_col = screen->max_col + 1;
		ws.ws_xpixel = FullWidth(screen);
		ws.ws_ypixel = FullHeight(screen);
	}
#endif	/* TIOCSWINSZ */
#endif	/* sun */

	if (!am_slave) {
#ifdef USE_HANDSHAKE
	    if (pipe(pc_pipe) || pipe(cp_pipe))
		SysError (ERROR_FORK);
#endif
	    if ((screen->pid = fork ()) == -1)
		SysError (ERROR_FORK);
		
	    if (screen->pid == 0) {
		/*