grub-mkimage.c

最新的grub2源代码

/* grub-mkimage.c - make a bootable image */
/*
 *  GRUB  --  GRand Unified Bootloader
 *  Copyright (C) 2002,2003,2004,2005  Free Software Foundation, Inc.
 *
 *  GRUB 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 GRUB; if not, write to the Free Software
 *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#include <config.h>
#include <grub/types.h>
#include <grub/machine/boot.h>
#include <grub/machine/kernel.h>
#include <grub/kernel.h>
#include <grub/disk.h>
#include <grub/util/misc.h>
#include <grub/util/resolve.h>

#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <stdlib.h>

#define _GNU_SOURCE	1
#include <getopt.h>

#if defined(HAVE_LZO_LZO1X_H)
# include <lzo/lzo1x.h>
#elif defined(HAVE_LZO1X_H)
# include <lzo1x.h>
#endif

static void
compress_kernel (char *kernel_img, size_t kernel_size,
		 char **core_img, size_t *core_size)
{
  lzo_uint size;
  char *wrkmem;
  
  grub_util_info ("kernel_img=%p, kernel_size=0x%x", kernel_img, kernel_size);
  if (kernel_size < GRUB_KERNEL_MACHINE_RAW_SIZE)
    grub_util_error ("the core image is too small");
  
  if (lzo_init () != LZO_E_OK)
    grub_util_error ("cannot initialize LZO");

  *core_img = xmalloc (kernel_size + kernel_size / 64 + 16 + 3);
  wrkmem = xmalloc (LZO1X_999_MEM_COMPRESS);

  memcpy (*core_img, kernel_img, GRUB_KERNEL_MACHINE_RAW_SIZE);
  
  grub_util_info ("compressing the core image");
  if (lzo1x_999_compress (kernel_img + GRUB_KERNEL_MACHINE_RAW_SIZE,
			  kernel_size - GRUB_KERNEL_MACHINE_RAW_SIZE,
			  *core_img + GRUB_KERNEL_MACHINE_RAW_SIZE,
			  &size, wrkmem)
      != LZO_E_OK)
    grub_util_error ("cannot compress the kernel image");

  free (wrkmem);

  *core_size = (size_t) size + GRUB_KERNEL_MACHINE_RAW_SIZE;
}

static void
generate_image (const char *dir, FILE *out, char *mods[])
{
  grub_addr_t module_addr = 0;
  char *kernel_img, *boot_img, *core_img;
  size_t kernel_size, boot_size, total_module_size, core_size;
  char *kernel_path, *boot_path;
  unsigned num;
  size_t offset;
  struct grub_util_path_list *path_list, *p, *next;
  struct grub_module_info *modinfo;

  path_list = grub_util_resolve_dependencies (dir, "moddep.lst", mods);

  kernel_path = grub_util_get_path (dir, "kernel.img");
  kernel_size = grub_util_get_image_size (kernel_path);

  total_module_size = sizeof (struct grub_module_info);
  for (p = path_list; p; p = p->next)
    total_module_size += (grub_util_get_image_size (p->name)
			  + sizeof (struct grub_module_header));

  grub_util_info ("the total module size is 0x%x", total_module_size);

  kernel_img = xmalloc (kernel_size + total_module_size);
  grub_util_load_image (kernel_path, kernel_img);

  /* Fill in the grub_module_info structure.  */
  modinfo = (struct grub_module_info *) (kernel_img + kernel_size);
  modinfo->magic = GRUB_MODULE_MAGIC;
  modinfo->offset = sizeof (struct grub_module_info);
  modinfo->size = total_module_size;

  offset = kernel_size + sizeof (struct grub_module_info);
  for (p = path_list; p; p = p->next)
    {
      struct grub_module_header *header;
      size_t mod_size;

      mod_size = grub_util_get_image_size (p->name);
      
      header = (struct grub_module_header *) (kernel_img + offset);
      header->offset = grub_cpu_to_le32 (sizeof (*header));
      header->size = grub_cpu_to_le32 (mod_size + sizeof (*header));
      
      grub_util_load_image (p->name, kernel_img + offset + sizeof (*header));

      offset += sizeof (*header) + mod_size;
    }

  compress_kernel (kernel_img, kernel_size + total_module_size,
		   &core_img, &core_size);

  grub_util_info ("the core size is 0x%x", core_size);
  
  num = ((core_size + GRUB_DISK_SECTOR_SIZE - 1) >> GRUB_DISK_SECTOR_BITS);
  if (num > 0xffff)
    grub_util_error ("the core image is too big");

  boot_path = grub_util_get_path (dir, "diskboot.img");
  boot_size = grub_util_get_image_size (boot_path);
  if (boot_size != GRUB_DISK_SECTOR_SIZE)
    grub_util_error ("diskboot.img is not one sector size");
  
  boot_img = grub_util_read_image (boot_path);
  
  /* i386 is a little endian architecture.  */
  *((grub_uint16_t *) (boot_img + GRUB_DISK_SECTOR_SIZE
		       - GRUB_BOOT_MACHINE_LIST_SIZE + 4))
    = grub_cpu_to_le16 (num);

  grub_util_write_image (boot_img, boot_size, out);
  free (boot_img);
  free (boot_path);
  
  module_addr = (path_list
		 ? (GRUB_BOOT_MACHINE_KERNEL_ADDR + GRUB_DISK_SECTOR_SIZE
		    + kernel_size)
		 : 0);

  grub_util_info ("the first module address is 0x%x", module_addr);
  *((grub_uint32_t *) (core_img + GRUB_KERNEL_MACHINE_TOTAL_MODULE_SIZE))
    = grub_cpu_to_le32 (total_module_size);
  *((grub_uint32_t *) (core_img + GRUB_KERNEL_MACHINE_KERNEL_IMAGE_SIZE))
    = grub_cpu_to_le32 (kernel_size);
  *((grub_uint32_t *) (core_img + GRUB_KERNEL_MACHINE_COMPRESSED_SIZE))
    = grub_cpu_to_le32 (core_size - GRUB_KERNEL_MACHINE_RAW_SIZE);
  
  grub_util_write_image (core_img, core_size, out);
  free (kernel_img);
  free (core_img);
  free (kernel_path);

  while (path_list)
    {
      next = path_list->next;
      free ((void *) path_list->name);
      free (path_list);
      path_list = next;
    }
}



static struct option options[] =
  {
    {"directory", required_argument, 0, 'd'},
    {"output", required_argument, 0, 'o'},
    {"help", no_argument, 0, 'h'},
    {"version", no_argument, 0, 'V'},
    {"verbose", no_argument, 0, 'v'},
    {0, 0, 0, 0}
  };

static void
usage (int status)
{
  if (status)
    fprintf (stderr, "Try ``grub-mkimage --help'' for more information.\n");
  else
    printf ("\
Usage: grub-mkimage [OPTION]... [MODULES]\n\
\n\
Make a bootable image of GRUB.\n\
\n\
  -d, --directory=DIR     use images and modules under DIR [default=%s]\n\
  -o, --output=FILE       output a generated image to FILE [default=stdout]\n\
  -h, --help              display this message and exit\n\
  -V, --version           print version information and exit\n\
  -v, --verbose           print verbose messages\n\
\n\
Report bugs to <%s>.\n\
", GRUB_DATADIR, PACKAGE_BUGREPORT);

  exit (status);
}

int
main (int argc, char *argv[])
{
  char *output = 0;
  char *dir = 0;
  FILE *fp = stdout;

  progname = "grub-mkimage";
  
  while (1)
    {
      int c = getopt_long (argc, argv, "d:o:hVv", options, 0);

      if (c == -1)
	break;
      else
	switch (c)
	  {
	  case 'o':
	    if (output)
	      free (output);
	    
	    output = xstrdup (optarg);
	    break;

	  case 'd':
	    if (dir)
	      free (dir);

	    dir = xstrdup (optarg);
	    break;

	  case 'h':
	    usage (0);
	    break;

	  case 'V':
	    printf ("grub-mkimage (%s) %s\n", PACKAGE_NAME, PACKAGE_VERSION);
	    return 0;

	  case 'v':
	    verbosity++;
	    break;

	  default:
	    usage (1);
	    break;
	  }
    }

  if (output)
    {
      fp = fopen (output, "wb");
      if (! fp)
	grub_util_error ("cannot open %s", output);
    }

  generate_image (dir ? : GRUB_DATADIR, fp, argv + optind);

  fclose (fp);

  if (dir)
    free (dir);

  return 0;
}