char_io.c

i386的bootloader源码grub

/* char_io.c - basic console input and output */
/*
 *  GRUB  --  GRand Unified Bootloader
 *  Copyright (C) 1999,2000,2001,2002,2004  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>

#ifdef SUPPORT_HERCULES
# include <hercules.h>
#endif

#ifdef SUPPORT_SERIAL
# include <serial.h>
#endif

#ifndef STAGE1_5
struct term_entry term_table[] =
  {
    {
      "console",
      0,
      console_putchar,
      console_checkkey,
      console_getkey,
      console_getxy,
      console_gotoxy,
      console_cls,
      console_setcolorstate,
      console_setcolor,
      console_setcursor
    },
#ifdef SUPPORT_SERIAL
    {
      "serial",
      /* A serial device must be initialized.  */
      TERM_NEED_INIT,
      serial_putchar,
      serial_checkkey,
      serial_getkey,
      serial_getxy,
      serial_gotoxy,
      serial_cls,
      serial_setcolorstate,
      0,
      0
    },
#endif /* SUPPORT_SERIAL */
#ifdef SUPPORT_HERCULES
    {
      "hercules",
      0,
      hercules_putchar,
      console_checkkey,
      console_getkey,
      hercules_getxy,
      hercules_gotoxy,
      hercules_cls,
      hercules_setcolorstate,
      hercules_setcolor,
      hercules_setcursor
    },      
#endif /* SUPPORT_HERCULES */
    /* This must be the last entry.  */
    { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }
  };

/* This must be console.  */
struct term_entry *current_term = term_table;

int max_lines = 24;
int count_lines = -1;
int use_pager = 1;
#endif

void
print_error (void)
{
  if (errnum > ERR_NONE && errnum < MAX_ERR_NUM)
#ifndef STAGE1_5
    /* printf("\7\n %s\n", err_list[errnum]); */
    printf ("\nError %u: %s\n", errnum, err_list[errnum]);
#else /* STAGE1_5 */
    printf ("Error %u\n", errnum);
#endif /* STAGE1_5 */
}

char *
convert_to_ascii (char *buf, int c,...)
{
  unsigned long num = *((&c) + 1), mult = 10;
  char *ptr = buf;

#ifndef STAGE1_5
  if (c == 'x' || c == 'X')
    mult = 16;

  if ((num & 0x80000000uL) && c == 'd')
    {
      num = (~num) + 1;
      *(ptr++) = '-';
      buf++;
    }
#endif

  do
    {
      int dig = num % mult;
      *(ptr++) = ((dig > 9) ? dig + 'a' - 10 : '0' + dig);
    }
  while (num /= mult);

  /* reorder to correct direction!! */
  {
    char *ptr1 = ptr - 1;
    char *ptr2 = buf;
    while (ptr1 > ptr2)
      {
	int tmp = *ptr1;
	*ptr1 = *ptr2;
	*ptr2 = tmp;
	ptr1--;
	ptr2++;
      }
  }

  return ptr;
}

void
grub_putstr (const char *str)
{
  while (*str)
    grub_putchar (*str++);
}

void
grub_printf (const char *format,...)
{
  int *dataptr = (int *) &format;
  char c, str[16];
  
  dataptr++;

  while ((c = *(format++)) != 0)
    {
      if (c != '%')
	grub_putchar (c);
      else
	switch (c = *(format++))
	  {
#ifndef STAGE1_5
	  case 'd':
	  case 'x':
	  case 'X':
#endif
	  case 'u':
	    *convert_to_ascii (str, c, *((unsigned long *) dataptr++)) = 0;
	    grub_putstr (str);
	    break;

#ifndef STAGE1_5
	  case 'c':
	    grub_putchar ((*(dataptr++)) & 0xff);
	    break;

	  case 's':
	    grub_putstr ((char *) *(dataptr++));
	    break;
#endif
	  }
    }
}

#ifndef STAGE1_5
int
grub_sprintf (char *buffer, const char *format, ...)
{
  /* XXX hohmuth
     ugly hack -- should unify with printf() */
  int *dataptr = (int *) &format;
  char c, *ptr, str[16];
  char *bp = buffer;

  dataptr++;

  while ((c = *format++) != 0)
    {
      if (c != '%')
	*bp++ = c; /* putchar(c); */
      else
	switch (c = *(format++))
	  {
	  case 'd': case 'u': case 'x':
	    *convert_to_ascii (str, c, *((unsigned long *) dataptr++)) = 0;

	    ptr = str;

	    while (*ptr)
	      *bp++ = *(ptr++); /* putchar(*(ptr++)); */
	    break;

	  case 'c': *bp++ = (*(dataptr++))&0xff;
	    /* putchar((*(dataptr++))&0xff); */
	    break;

	  case 's':
	    ptr = (char *) (*(dataptr++));

	    while ((c = *ptr++) != 0)
	      *bp++ = c; /* putchar(c); */
	    break;
	  }
    }

  *bp = 0;
  return bp - buffer;
}


void
init_page (void)
{
  cls ();

  grub_printf ("\n    GNU GRUB  version %s  (%dK lower / %dK upper memory)\n\n",
	  version_string, mbi.mem_lower, mbi.mem_upper);
}

/* The number of the history entries.  */
static int num_history = 0;

/* Get the NOth history. If NO is less than zero or greater than or
   equal to NUM_HISTORY, return NULL. Otherwise return a valid string.  */
static char *
get_history (int no)
{
  if (no < 0 || no >= num_history)
    return 0;

  return (char *) HISTORY_BUF + MAX_CMDLINE * no;
}

/* Add CMDLINE to the history buffer.  */
static void
add_history (const char *cmdline, int no)
{
  grub_memmove ((char *) HISTORY_BUF + MAX_CMDLINE * (no + 1),
		(char *) HISTORY_BUF + MAX_CMDLINE * no,
		MAX_CMDLINE * (num_history - no));
  grub_strcpy ((char *) HISTORY_BUF + MAX_CMDLINE * no, cmdline);
  if (num_history < HISTORY_SIZE)
    num_history++;
}

static int
real_get_cmdline (char *prompt, char *cmdline, int maxlen,
		  int echo_char, int readline)
{
  /* This is a rather complicated function. So explain the concept.
     
     A command-line consists of ``section''s. A section is a part of the
     line which may be displayed on the screen, but a section is never
     displayed with another section simultaneously.

     Each section is basically 77 or less characters, but the exception
     is the first section, which is 78 or less characters, because the
     starting point is special. See below.

     The first section contains a prompt and a command-line (or the
     first part of a command-line when it is too long to be fit in the
     screen). So, in the first section, the number of command-line
     characters displayed is 78 minus the length of the prompt (or
     less). If the command-line has more characters, `>' is put at the
     position 78 (zero-origin), to inform the user of the hidden
     characters.

     Other sections always have `<' at the first position, since there
     is absolutely a section before each section. If there is a section
     after another section, this section consists of 77 characters and
     `>' at the last position. The last section has 77 or less
     characters and doesn't have `>'.

     Each section other than the last shares some characters with the
     previous section. This region is called ``margin''. If the cursor
     is put at the magin which is shared by the first section and the
     second, the first section is displayed. Otherwise, a displayed
     section is switched to another section, only if the cursor is put
     outside that section.  */

  /* XXX: These should be defined in shared.h, but I leave these here,
     until this code is freezed.  */
#define CMDLINE_WIDTH	78
#define CMDLINE_MARGIN	10
  
  int xpos, lpos, c, section;
  /* The length of PROMPT.  */
  int plen;
  /* The length of the command-line.  */
  int llen;
  /* The index for the history.  */
  int history = -1;
  /* The working buffer for the command-line.  */
  char *buf = (char *) CMDLINE_BUF;
  /* The kill buffer.  */
  char *kill_buf = (char *) KILL_BUF;
  
  /* Nested function definitions for code simplicity.  */

  /* The forward declarations of nested functions are prefixed
     with `auto'.  */
  auto void cl_refresh (int full, int len);
  auto void cl_backward (int count);
  auto void cl_forward (int count);
  auto void cl_insert (const char *str);
  auto void cl_delete (int count);
  auto void cl_init (void);
  
  /* Move the cursor backward.  */
  void cl_backward (int count)
    {
      lpos -= count;
      
      /* If the cursor is in the first section, display the first section
	 instead of the second.  */
      if (section == 1 && plen + lpos < CMDLINE_WIDTH)
	cl_refresh (1, 0);
      else if (xpos - count < 1)
	cl_refresh (1, 0);
      else
	{
	  xpos -= count;

	  if (current_term->flags & TERM_DUMB)
	    {
	      int i;
	      
	      for (i = 0; i < count; i++)
		grub_putchar ('\b');
	    }
	  else
	    gotoxy (xpos, getxy () & 0xFF);
	}
    }

  /* Move the cursor forward.  */
  void cl_forward (int count)
    {
      lpos += count;

      /* If the cursor goes outside, scroll the screen to the right.  */
      if (xpos + count >= CMDLINE_WIDTH)
	cl_refresh (1, 0);
      else
	{
	  xpos += count;

	  if (current_term->flags & TERM_DUMB)
	    {
	      int i;
	      
	      for (i = lpos - count; i < lpos; i++)
		{
		  if (! echo_char)
		    grub_putchar (buf[i]);
		  else
		    grub_putchar (echo_char);
		}
	    }
	  else
	    gotoxy (xpos, getxy () & 0xFF);
	}
    }

  /* Refresh the screen. If FULL is true, redraw the full line, otherwise,
     only LEN characters from LPOS.  */
  void cl_refresh (int full, int len)
    {
      int i;
      int start;
      int pos = xpos;
      
      if (full)
	{
	  /* Recompute the section number.  */
	  if (lpos + plen < CMDLINE_WIDTH)
	    section = 0;
	  else
	    section = ((lpos + plen - CMDLINE_WIDTH)
		       / (CMDLINE_WIDTH - 1 - CMDLINE_MARGIN) + 1);

	  /* From the start to the end.  */
	  len = CMDLINE_WIDTH;
	  pos = 0;
	  grub_putchar ('\r');

	  /* If SECTION is the first section, print the prompt, otherwise,
	     print `<'.  */
	  if (section == 0)
	    {
	      grub_printf ("%s", prompt);
	      len -= plen;
	      pos += plen;
	    }
	  else
	    {
	      grub_putchar ('<');
	      len--;
	      pos++;
	    }
	}

      /* Compute the index to start writing BUF and the resulting position
	 on the screen.  */
      if (section == 0)
	{
	  int offset = 0;
	  
	  if (! full)
	    offset = xpos - plen;
	  
	  start = 0;
	  xpos = lpos + plen;
	  start += offset;
	}
      else
	{
	  int offset = 0;
	  
	  if (! full)
	    offset = xpos - 1;
	  
	  start = ((section - 1) * (CMDLINE_WIDTH - 1 - CMDLINE_MARGIN)
		   + CMDLINE_WIDTH - plen - CMDLINE_MARGIN);
	  xpos = lpos + 1 - start;
	  start += offset;
	}

      /* Print BUF. If ECHO_CHAR is not zero, put it instead.  */
      for (i = start; i < start + len && i < llen; i++)
	{
	  if (! echo_char)
	    grub_putchar (buf[i]);
	  else
	    grub_putchar (echo_char);

	  pos++;
	}
      
      /* Fill up the rest of the line with spaces.  */
      for (; i < start + len; i++)
	{
	  grub_putchar (' ');
	  pos++;
	}
      
      /* If the cursor is at the last position, put `>' or a space,
	 depending on if there are more characters in BUF.  */
      if (pos == CMDLINE_WIDTH)
	{
	  if (start + len < llen)
	    grub_putchar ('>');
	  else
	    grub_putchar (' ');
	  
	  pos++;
	}
      
      /* Back to XPOS.  */
      if (current_term->flags & TERM_DUMB)
	{
	  for (i = 0; i < pos - xpos; i++)
	    grub_putchar ('\b');
	}
      else
	gotoxy (xpos, getxy () & 0xFF);
    }

  /* Initialize the command-line.  */
  void cl_init (void)
    {
      /* Distinguish us from other lines and error messages!  */
      grub_putchar ('\n');

      /* Print full line and set position here.  */
      cl_refresh (1, 0);
    }

  /* Insert STR to BUF.  */
  void cl_insert (const char *str)
    {
      int l = grub_strlen (str);

      if (llen + l < maxlen)
	{
	  if (lpos == llen)
	    grub_memmove (buf + lpos, str, l + 1);
	  else
	    {
	      grub_memmove (buf + lpos + l, buf + lpos, llen - lpos + 1);
	      grub_memmove (buf + lpos, str, l);
	    }
	  
	  llen += l;
	  lpos += l;
	  if (xpos + l >= CMDLINE_WIDTH)
	    cl_refresh (1, 0);
	  else if (xpos + l + llen - lpos > CMDLINE_WIDTH)
	    cl_refresh (0, CMDLINE_WIDTH - xpos);
	  else
	    cl_refresh (0, l + llen - lpos);
	}
    }

  /* Delete COUNT characters in BUF.  */
  void cl_delete (int count)
    {
      grub_memmove (buf + lpos, buf + lpos + count, llen - count + 1);
      llen -= count;
      
      if (xpos + llen + count - lpos > CMDLINE_WIDTH)
	cl_refresh (0, CMDLINE_WIDTH - xpos);
      else
	cl_refresh (0, llen + count - lpos);
    }

  plen = grub_strlen (prompt);
  llen = grub_strlen (cmdline);

  if (maxlen > MAX_CMDLINE)
    {
      maxlen = MAX_CMDLINE;
      if (llen >= MAX_CMDLINE)
	{
	  llen = MAX_CMDLINE - 1;
	  cmdline[MAX_CMDLINE] = 0;
	}
    }
  lpos = llen;
  grub_strcpy (buf, cmdline);

  cl_init ();

  while ((c = ASCII_CHAR (getkey ())) != '\n' && c != '\r')
    {
      /* If READLINE is non-zero, handle readline-like key bindings.  */
      if (readline)
	{
	  switch (c)
	    {
	    case 9:		/* TAB lists completions */
	      {
		int i;
		/* POS points to the first space after a command.  */
		int pos = 0;
		int ret;
		char *completion_buffer = (char *) COMPLETION_BUF;
		int equal_pos = -1;
		int is_filename;

		/* Find the first word.  */
		while (buf[pos] == ' ')
		  pos++;
		while (buf[pos] && buf[pos] != '=' && buf[pos] != ' ')
		  pos++;

		is_filename = (lpos > pos);

		/* Find the position of the equal character after a
		   command, and replace it with a space.  */
		for (i = pos; buf[i] && buf[i] != ' '; i++)
		  if (buf[i] == '=')
		    {
		      equal_pos = i;
		      buf[i] = ' ';
		      break;
		    }

		/* Find the position of the first character in this
		   word.  */
		for (i = lpos; i > 0 && buf[i - 1] != ' '; i--)
		  ;

		/* Invalidate the cache, because the user may exchange
		   removable disks.  */
		buf_drive = -1;

		/* Copy this word to COMPLETION_BUFFER and do the
		   completion.  */
		grub_memmove (completion_buffer, buf + i, lpos - i);
		completion_buffer[lpos - i] = 0;
		ret = print_completions (is_filename, 1);
		errnum = ERR_NONE;

		if (ret >= 0)
		  {
		    /* Found, so insert COMPLETION_BUFFER.  */
		    cl_insert (completion_buffer + lpos - i);

		    if (ret > 0)
		      {
			/* There are more than one candidates, so print
			   the list.  */
			grub_putchar ('\n');
			print_completions (is_filename, 0);
			errnum = ERR_NONE;
		      }
		  }

		/* Restore the command-line.  */
		if (equal_pos >= 0)
		  buf[equal_pos] = '=';

		if (ret)
		  cl_init ();
	      }
	      break;
	    case 1:		/* C-a go to beginning of line */
	      cl_backward (lpos);
	      break;
	    case 5:		/* C-e go to end of line */
	      cl_forward (llen - lpos);
	      break;
	    case 6:		/* C-f forward one character */
	      if (lpos < llen)
		cl_forward (1);