stage2.c

i386的bootloader源码grub

/*
 *  GRUB  --  GRand Unified Bootloader
 *  Copyright (C) 2000,2001,2002,2004  Free Software Foundation, Inc.
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#include <shared.h>
#include <term.h>

grub_jmp_buf restart_env;

#if defined(PRESET_MENU_STRING) || defined(SUPPORT_DISKLESS)

# if defined(PRESET_MENU_STRING)
static const char *preset_menu = PRESET_MENU_STRING;
# elif defined(SUPPORT_DISKLESS)
/* Execute the command "bootp" automatically.  */
static const char *preset_menu = "bootp\n";
# endif /* SUPPORT_DISKLESS */

static int preset_menu_offset;

static int
open_preset_menu (void)
{
#ifdef GRUB_UTIL
  /* Unless the user explicitly requests to use the preset menu,
     always opening the preset menu fails in the grub shell.  */
  if (! use_preset_menu)
    return 0;
#endif /* GRUB_UTIL */
  
  preset_menu_offset = 0;
  return preset_menu != 0;
}

static int
read_from_preset_menu (char *buf, int maxlen)
{
  int len = grub_strlen (preset_menu + preset_menu_offset);

  if (len > maxlen)
    len = maxlen;

  grub_memmove (buf, preset_menu + preset_menu_offset, len);
  preset_menu_offset += len;

  return len;
}

static void
close_preset_menu (void)
{
  /* Disable the preset menu.  */
  preset_menu = 0;
}

#else /* ! PRESET_MENU_STRING && ! SUPPORT_DISKLESS */

#define open_preset_menu()	0
#define read_from_preset_menu(buf, maxlen)	0
#define close_preset_menu()

#endif /* ! PRESET_MENU_STRING && ! SUPPORT_DISKLESS */

static char *
get_entry (char *list, int num, int nested)
{
  int i;

  for (i = 0; i < num; i++)
    {
      do
	{
	  while (*(list++));
	}
      while (nested && *(list++));
    }

  return list;
}

/* Print an entry in a line of the menu box.  */
static void
print_entry (int y, int highlight, char *entry)
{
  int x;

  if (current_term->setcolorstate)
    current_term->setcolorstate (COLOR_STATE_NORMAL);
  
  if (highlight && current_term->setcolorstate)
    current_term->setcolorstate (COLOR_STATE_HIGHLIGHT);

  gotoxy (2, y);
  grub_putchar (' ');
  for (x = 3; x < 75; x++)
    {
      if (*entry && x <= 72)
	{
	  if (x == 72)
	    grub_putchar (DISP_RIGHT);
	  else
	    grub_putchar (*entry++);
	}
      else
	grub_putchar (' ');
    }
  gotoxy (74, y);

  if (current_term->setcolorstate)
    current_term->setcolorstate (COLOR_STATE_STANDARD);
}

/* Print entries in the menu box.  */
static void
print_entries (int y, int size, int first, int entryno, char *menu_entries)
{
  int i;
  
  gotoxy (77, y + 1);

  if (first)
    grub_putchar (DISP_UP);
  else
    grub_putchar (' ');

  menu_entries = get_entry (menu_entries, first, 0);

  for (i = 0; i < size; i++)
    {
      print_entry (y + i + 1, entryno == i, menu_entries);

      while (*menu_entries)
	menu_entries++;

      if (*(menu_entries - 1))
	menu_entries++;
    }

  gotoxy (77, y + size);

  if (*menu_entries)
    grub_putchar (DISP_DOWN);
  else
    grub_putchar (' ');

  gotoxy (74, y + entryno + 1);
}

static void
print_entries_raw (int size, int first, char *menu_entries)
{
  int i;

#define LINE_LENGTH 67

  for (i = 0; i < LINE_LENGTH; i++)
    grub_putchar ('-');
  grub_putchar ('\n');

  for (i = first; i < size; i++)
    {
      /* grub's printf can't %02d so ... */
      if (i < 10)
	grub_putchar (' ');
      grub_printf ("%d: %s\n", i, get_entry (menu_entries, i, 0));
    }

  for (i = 0; i < LINE_LENGTH; i++)
    grub_putchar ('-');
  grub_putchar ('\n');

#undef LINE_LENGTH
}


static void
print_border (int y, int size)
{
  int i;

  if (current_term->setcolorstate)
    current_term->setcolorstate (COLOR_STATE_NORMAL);
  
  gotoxy (1, y);

  grub_putchar (DISP_UL);
  for (i = 0; i < 73; i++)
    grub_putchar (DISP_HORIZ);
  grub_putchar (DISP_UR);

  i = 1;
  while (1)
    {
      gotoxy (1, y + i);

      if (i > size)
	break;
      
      grub_putchar (DISP_VERT);
      gotoxy (75, y + i);
      grub_putchar (DISP_VERT);

      i++;
    }

  grub_putchar (DISP_LL);
  for (i = 0; i < 73; i++)
    grub_putchar (DISP_HORIZ);
  grub_putchar (DISP_LR);

  if (current_term->setcolorstate)
    current_term->setcolorstate (COLOR_STATE_STANDARD);
}

static void
run_menu (char *menu_entries, char *config_entries, int num_entries,
	  char *heap, int entryno)
{
  int c, time1, time2 = -1, first_entry = 0;
  char *cur_entry = 0;

  /*
   *  Main loop for menu UI.
   */

restart:
  /* Dumb terminal always use all entries for display 
     invariant for TERM_DUMB: first_entry == 0  */
  if (! (current_term->flags & TERM_DUMB))
    {
      while (entryno > 11)
	{
	  first_entry++;
	  entryno--;
	}
    }

  /* If the timeout was expired or wasn't set, force to show the menu
     interface. */
  if (grub_timeout < 0)
    show_menu = 1;
  
  /* If SHOW_MENU is false, don't display the menu until ESC is pressed.  */
  if (! show_menu)
    {
      /* Get current time.  */
      while ((time1 = getrtsecs ()) == 0xFF)
	;

      while (1)
	{
	  /* Check if ESC is pressed.  */
	  if (checkkey () != -1 && ASCII_CHAR (getkey ()) == '\e')
	    {
	      grub_timeout = -1;
	      show_menu = 1;
	      break;
	    }

	  /* If GRUB_TIMEOUT is expired, boot the default entry.  */
	  if (grub_timeout >=0
	      && (time1 = getrtsecs ()) != time2
	      && time1 != 0xFF)
	    {
	      if (grub_timeout <= 0)
		{
		  grub_timeout = -1;
		  goto boot_entry;
		}
	      
	      time2 = time1;
	      grub_timeout--;
	      
	      /* Print a message.  */
	      grub_printf ("\rPress `ESC' to enter the menu... %d   ",
			   grub_timeout);
	    }
	}
    }

  /* Only display the menu if the user wants to see it. */
  if (show_menu)
    {
      init_page ();
      setcursor (0);

      if (current_term->flags & TERM_DUMB)
	print_entries_raw (num_entries, first_entry, menu_entries);
      else
	print_border (3, 12);

      grub_printf ("\n\
      Use the %c and %c keys to select which entry is highlighted.\n",
		   DISP_UP, DISP_DOWN);
      
      if (! auth && password)
	{
	  printf ("\
      Press enter to boot the selected OS or \'p\' to enter a\n\
      password to unlock the next set of features.");
	}
      else
	{
	  if (config_entries)
	    printf ("\
      Press enter to boot the selected OS, \'e\' to edit the\n\
      commands before booting, or \'c\' for a command-line.");
	  else
	    printf ("\
      Press \'b\' to boot, \'e\' to edit the selected command in the\n\
      boot sequence, \'c\' for a command-line, \'o\' to open a new line\n\
      after (\'O\' for before) the selected line, \'d\' to remove the\n\
      selected line, or escape to go back to the main menu.");
	}

      if (current_term->flags & TERM_DUMB)
	grub_printf ("\n\nThe selected entry is %d ", entryno);
      else
	print_entries (3, 12, first_entry, entryno, menu_entries);
    }

  /* XX using RT clock now, need to initialize value */
  while ((time1 = getrtsecs()) == 0xFF);

  while (1)
    {
      /* Initialize to NULL just in case...  */
      cur_entry = NULL;

      if (grub_timeout >= 0 && (time1 = getrtsecs()) != time2 && time1 != 0xFF)
	{
	  if (grub_timeout <= 0)
	    {
	      grub_timeout = -1;
	      break;
	    }

	  /* else not booting yet! */
	  time2 = time1;

	  if (current_term->flags & TERM_DUMB)
	      grub_printf ("\r    Entry %d will be booted automatically in %d seconds.   ", 
			   entryno, grub_timeout);
	  else
	    {
	      gotoxy (3, 22);
	      grub_printf ("The highlighted entry will be booted automatically in %d seconds.    ",
			   grub_timeout);
	      gotoxy (74, 4 + entryno);
	  }
	  
	  grub_timeout--;
	}

      /* Check for a keypress, however if TIMEOUT has been expired
	 (GRUB_TIMEOUT == -1) relax in GETKEY even if no key has been
	 pressed.  
	 This avoids polling (relevant in the grub-shell and later on
	 in grub if interrupt driven I/O is done).  */
      if (checkkey () >= 0 || grub_timeout < 0)
	{
	  /* Key was pressed, show which entry is selected before GETKEY,
	     since we're comming in here also on GRUB_TIMEOUT == -1 and
	     hang in GETKEY */
	  if (current_term->flags & TERM_DUMB)
	    grub_printf ("\r    Highlighted entry is %d: ", entryno);

	  c = ASCII_CHAR (getkey ());

	  if (grub_timeout >= 0)
	    {
	      if (current_term->flags & TERM_DUMB)
		grub_putchar ('\r');
	      else
		gotoxy (3, 22);
	      printf ("                                                                    ");
	      grub_timeout = -1;
	      fallback_entry = -1;
	      if (! (current_term->flags & TERM_DUMB))
		gotoxy (74, 4 + entryno);
	    }

	  /* We told them above (at least in SUPPORT_SERIAL) to use
	     '^' or 'v' so accept these keys.  */
	  if (c == 16 || c == '^')
	    {
	      if (current_term->flags & TERM_DUMB)
		{
		  if (entryno > 0)
		    entryno--;
		}
	      else
		{
		  if (entryno > 0)
		    {
		      print_entry (4 + entryno, 0,
				   get_entry (menu_entries,
					      first_entry + entryno,
					      0));
		      entryno--;
		      print_entry (4 + entryno, 1,
				   get_entry (menu_entries,
					      first_entry + entryno,
					      0));
		    }
		  else if (first_entry > 0)
		    {
		      first_entry--;
		      print_entries (3, 12, first_entry, entryno,
				     menu_entries);
		    }
		}
	    }
	  else if ((c == 14 || c == 'v')
		   && first_entry + entryno + 1 < num_entries)
	    {
	      if (current_term->flags & TERM_DUMB)
		entryno++;
	      else
		{
		  if (entryno < 11)
		    {
		      print_entry (4 + entryno, 0,
				   get_entry (menu_entries,
					      first_entry + entryno,
					      0));
		      entryno++;
		      print_entry (4 + entryno, 1,
				   get_entry (menu_entries,
					      first_entry + entryno,
					      0));
		  }
		else if (num_entries > 12 + first_entry)
		  {
		    first_entry++;
		    print_entries (3, 12, first_entry, entryno, menu_entries);
		  }
		}
	    }
	  else if (c == 7)
	    {
	      /* Page Up */
	      first_entry -= 12;
	      if (first_entry < 0)
		{
		  entryno += first_entry;
		  first_entry = 0;
		  if (entryno < 0)
		    entryno = 0;
		}
	      print_entries (3, 12, first_entry, entryno, menu_entries);
	    }
	  else if (c == 3)
	    {
	      /* Page Down */
	      first_entry += 12;
	      if (first_entry + entryno + 1 >= num_entries)
		{
		  first_entry = num_entries - 12;
		  if (first_entry < 0)
		    first_entry = 0;
		  entryno = num_entries - first_entry - 1;
		}
	      print_entries (3, 12, first_entry, entryno, menu_entries);
	    }

	  if (config_entries)
	    {
	      if ((c == '\n') || (c == '\r') || (c == 6))
		break;
	    }
	  else
	    {
	      if ((c == 'd') || (c == 'o') || (c == 'O'))
		{
		  if (! (current_term->flags & TERM_DUMB))
		    print_entry (4 + entryno, 0,
				 get_entry (menu_entries,
					    first_entry + entryno,
					    0));

		  /* insert after is almost exactly like insert before */
		  if (c == 'o')
		    {
		      /* But `o' differs from `O', since it may causes
			 the menu screen to scroll up.  */
		      if (entryno < 11 || (current_term->flags & TERM_DUMB))
			entryno++;
		      else