[grub2.git] / fs / sfs.c

/* sfs.c - Amiga Smart FileSystem.  */
/*
 *  GRUB  --  GRand Unified Bootloader
 *  Copyright (C) 2005,2006,2007,2008  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 3 of the License, or
 *  (at your option) any later version.
 *
 *  GRUB 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, see <http://www.gnu.org/licenses/>.
 */

#include <grub/err.h>
#include <grub/file.h>
#include <grub/mm.h>
#include <grub/misc.h>
#include <grub/disk.h>
#include <grub/dl.h>
#include <grub/types.h>
#include <grub/fshelp.h>

/* The common header for a block.  */
struct grub_sfs_bheader
{
  grub_uint8_t magic[4];
  grub_uint32_t chksum;
  grub_uint32_t ipointtomyself;
} __attribute__ ((packed));

/* The sfs rootblock.  */
struct grub_sfs_rblock
{
  struct grub_sfs_bheader header;
  grub_uint32_t version;
  grub_uint8_t unused1[36];
  grub_uint32_t blocksize;
  grub_uint8_t unused2[40];
  grub_uint8_t unused3[8];
  grub_uint32_t rootobject;
  grub_uint32_t btree;
} __attribute__ ((packed));

/* A SFS object container.  */
struct grub_sfs_obj
{
  grub_uint8_t unused1[4];
  grub_uint32_t nodeid;
  grub_uint8_t unused2[4];
  union
  {
    struct
    {
      grub_uint32_t first_block;
      grub_uint32_t size;
    } file __attribute__ ((packed));
    struct
    {
      grub_uint32_t hashtable;
      grub_uint32_t dir_objc;
    } dir __attribute__ ((packed));
  } file_dir;
  grub_uint8_t unused3[4];
  grub_uint8_t type;
  grub_uint8_t filename[1];
  grub_uint8_t comment[1];
} __attribute__ ((packed));

#define	GRUB_SFS_TYPE_DELETED	32
#define	GRUB_SFS_TYPE_SYMLINK	64
#define	GRUB_SFS_TYPE_DIR	128

/* A SFS object container.  */
struct grub_sfs_objc
{
  struct grub_sfs_bheader header;
  grub_uint32_t parent;
  grub_uint32_t next;
  grub_uint32_t prev;
  /* The amount of objects depends on the blocksize.  */
  struct grub_sfs_obj objects[1];
} __attribute__ ((packed));

struct grub_sfs_btree_node
{
  grub_uint32_t key;
  grub_uint32_t data;
} __attribute__ ((packed));

struct grub_sfs_btree_extent
{
  grub_uint32_t key;
  grub_uint32_t next;
  grub_uint32_t prev;
  grub_uint16_t size;
} __attribute__ ((packed));

struct grub_sfs_btree
{
  struct grub_sfs_bheader header;
  grub_uint16_t nodes;
  grub_uint8_t leaf;
  grub_uint8_t nodesize;
  /* Normally this can be kind of node, but just extents are
     supported.  */
  struct grub_sfs_btree_node node[1];
} __attribute__ ((packed));

\f

struct grub_fshelp_node
{
  struct grub_sfs_data *data;
  int block;
  int size;
};

/* Information about a "mounted" sfs filesystem.  */
struct grub_sfs_data
{
  struct grub_sfs_rblock rblock;
  struct grub_fshelp_node diropen;
  grub_disk_t disk;

  /* Blocksize in sectors.  */
  unsigned int blocksize;

  /* Label of the filesystem.  */
  char *label;
};

static grub_dl_t my_mod;

\f
/* Lookup the extent starting with BLOCK in the filesystem described
   by DATA.  Return the extent size in SIZE and the following extent
   in NEXTEXT.  */
static grub_err_t
grub_sfs_read_extent (struct grub_sfs_data *data, unsigned int block,
		      int *size, int *nextext)
{
  char *treeblock;
  struct grub_sfs_btree *tree;
  int i;
  int next;
  int prev;

  treeblock = grub_malloc (data->blocksize);
  if (!block)
    return 0;

  next = grub_be_to_cpu32 (data->rblock.btree);
  tree = (struct grub_sfs_btree *) treeblock;

  /* Handle this level in the btree.  */
  do
    {
      prev = 0;

      grub_disk_read (data->disk, next, 0, data->blocksize, treeblock);
      if (grub_errno)
	{
	  grub_free (treeblock);
	  return grub_errno;
	}

      for (i = grub_be_to_cpu16 (tree->nodes) - 1; i >= 0; i--)
	{

#define EXTNODE(tree, index)						\
	((struct grub_sfs_btree_node *) (((char *) &(tree)->node[0])	\
					 + (index) * (tree)->nodesize))

	  /* Follow the tree down to the leaf level.  */
	  if ((grub_be_to_cpu32 (EXTNODE(tree, i)->key) <= block)
	      && !tree->leaf)
	    {
	      next = grub_be_to_cpu32 (EXTNODE (tree, i)->data);
	      break;
	    }

	  /* If the leaf level is reached, just find the correct extent.  */
	  if (grub_be_to_cpu32 (EXTNODE (tree, i)->key) == block && tree->leaf)
	    {
	      struct grub_sfs_btree_extent *extent;
	      extent = (struct grub_sfs_btree_extent *) EXTNODE (tree, i);

	      /* We found a correct leaf.  */
	      *size = grub_be_to_cpu16 (extent->size);
	      *nextext = grub_be_to_cpu32 (extent->next);

	      grub_free (treeblock);
	      return 0;
	    }

#undef EXTNODE

	}
    } while (!tree->leaf);

  grub_free (treeblock);

  return grub_error (GRUB_ERR_FILE_READ_ERROR, "SFS extent not found");
}

static grub_disk_addr_t
grub_sfs_read_block (grub_fshelp_node_t node, grub_disk_addr_t fileblock)
{
  int blk = node->block;
  int size = 0;
  int next = 0;

  while (blk)
    {
      grub_err_t err;

      /* In case of the first block we don't have to lookup the
	 extent, the minimum size is always 1.  */
      if (fileblock == 0)
	return blk;

      err = grub_sfs_read_extent (node->data, blk, &size, &next);
      if (err)
	return 0;

      if (fileblock < (unsigned int) size)
	return fileblock + blk;

      fileblock -= size;

      blk = next;
    }

  grub_error (GRUB_ERR_FILE_READ_ERROR,
	      "reading a SFS block outside the extent");

  return 0;
}


/* Read LEN bytes from the file described by DATA starting with byte
   POS.  Return the amount of read bytes in READ.  */
static grub_ssize_t
grub_sfs_read_file (grub_fshelp_node_t node,
		    void NESTED_FUNC_ATTR (*read_hook) (grub_disk_addr_t sector,
				       unsigned offset, unsigned length),
		    int pos, grub_size_t len, char *buf)
{
  return grub_fshelp_read_file (node->data->disk, node, read_hook,
				pos, len, buf, grub_sfs_read_block,
				node->size, 0);
}


static struct grub_sfs_data *
grub_sfs_mount (grub_disk_t disk)
{
  struct grub_sfs_data *data;
  struct grub_sfs_objc *rootobjc;
  char *rootobjc_data = 0;
  unsigned int blk;

  data = grub_malloc (sizeof (*data));
  if (!data)
    return 0;

  /* Read the rootblock.  */
  grub_disk_read (disk, 0, 0, sizeof (struct grub_sfs_rblock),
		  &data->rblock);
  if (grub_errno)
    goto fail;

  /* Make sure this is a sfs filesystem.  */
  if (grub_strncmp ((char *) (data->rblock.header.magic), "SFS", 4))
    {
      grub_error (GRUB_ERR_BAD_FS, "not a sfs filesystem");
      goto fail;
    }

  data->blocksize = grub_be_to_cpu32 (data->rblock.blocksize);
  rootobjc_data = grub_malloc (data->blocksize);
  if (! rootobjc_data)
    goto fail;

  /* Read the root object container.  */
  grub_disk_read (disk, grub_be_to_cpu32 (data->rblock.rootobject), 0,
		  data->blocksize, rootobjc_data);
  if (grub_errno)
    goto fail;

  rootobjc = (struct grub_sfs_objc *) rootobjc_data;

  blk = grub_be_to_cpu32 (rootobjc->objects[0].file_dir.dir.dir_objc);
  data->diropen.size = 0;
  data->diropen.block = blk;
  data->diropen.data = data;
  data->disk = disk;
  data->label = grub_strdup ((char *) (rootobjc->objects[0].filename));

  return data;

 fail:
  if (grub_errno == GRUB_ERR_OUT_OF_RANGE)
    grub_error (GRUB_ERR_BAD_FS, "not an sfs filesystem");

  grub_free (data);
  grub_free (rootobjc_data);
  return 0;
}


static char *
grub_sfs_read_symlink (grub_fshelp_node_t node)
{
  struct grub_sfs_data *data = node->data;
  char *symlink;
  char *block;

  block = grub_malloc (data->blocksize);
  if (!block)
    return 0;

  grub_disk_read (data->disk, node->block, 0, data->blocksize, block);
  if (grub_errno)
    {
      grub_free (block);
      return 0;
    }

  /* This is just a wild guess, but it always worked for me.  How the
     SLNK block looks like is not documented in the SFS docs.  */
  symlink = grub_strdup (&block[24]);
  grub_free (block);
  if (!symlink)
    return 0;

  return symlink;
}

static int
grub_sfs_iterate_dir (grub_fshelp_node_t dir,
		       int NESTED_FUNC_ATTR
		       (*hook) (const char *filename,
				enum grub_fshelp_filetype filetype,
				grub_fshelp_node_t node))
{
  struct grub_fshelp_node *node = 0;
  struct grub_sfs_data *data = dir->data;
  char *objc_data;
  struct grub_sfs_objc *objc;
  unsigned int next = dir->block;
  int pos;

  auto int NESTED_FUNC_ATTR grub_sfs_create_node (const char *name, int block,
						  int size, int type);

  int NESTED_FUNC_ATTR grub_sfs_create_node (const char *name, int block,
					     int size, int type)
    {
      node = grub_malloc (sizeof (*node));
      if (!node)
	return 1;

      node->data = data;
      node->size = size;
      node->block = block;

      return hook (name, type, node);
    }

  objc_data = grub_malloc (data->blocksize);
  if (!objc_data)
    goto fail;

  /* The Object container can consist of multiple blocks, iterate over
     every block.  */
  while (next)
    {
      grub_disk_read (data->disk, next, 0, data->blocksize, objc_data);
      if (grub_errno)
	goto fail;

      objc = (struct grub_sfs_objc *) objc_data;

      pos = (char *) &objc->objects[0] - (char *) objc;

      /* Iterate over all entries in this block.  */
      while (pos + sizeof (struct grub_sfs_obj) < data->blocksize)
	{
	  struct grub_sfs_obj *obj;
	  obj = (struct grub_sfs_obj *) ((char *) objc + pos);
	  char *filename = (char *) (obj->filename);
	  int len;
	  enum grub_fshelp_filetype type;
	  unsigned int block;

	  /* The filename and comment dynamically increase the size of
	     the object.  */
	  len = grub_strlen (filename);
	  len += grub_strlen (filename + len + 1);

	  pos += sizeof (*obj) + len;
	  /* Round up to a multiple of two bytes.  */
	  pos = ((pos + 1) >> 1) << 1;

	  if (grub_strlen (filename) == 0)
	    continue;

	  /* First check if the file was not deleted.  */
	  if (obj->type & GRUB_SFS_TYPE_DELETED)
	    continue;
	  else if (obj->type & GRUB_SFS_TYPE_SYMLINK)
	    type = GRUB_FSHELP_SYMLINK;
	  else if (obj->type & GRUB_SFS_TYPE_DIR)
	    type = GRUB_FSHELP_DIR;
	  else
	    type = GRUB_FSHELP_REG;

	  if (type == GRUB_FSHELP_DIR)
	    block = grub_be_to_cpu32 (obj->file_dir.dir.dir_objc);
	  else
	    block = grub_be_to_cpu32 (obj->file_dir.file.first_block);

	  if (grub_sfs_create_node (filename, block,
				    grub_be_to_cpu32 (obj->file_dir.file.size),
				    type))
	    {
	      grub_free (objc_data);
	      return 1;
	    }
	}

      next = grub_be_to_cpu32 (objc->next);
    }

 fail:
  grub_free (objc_data);
  return 0;
}


/* Open a file named NAME and initialize FILE.  */
static grub_err_t
grub_sfs_open (struct grub_file *file, const char *name)
{
  struct grub_sfs_data *data;
  struct grub_fshelp_node *fdiro = 0;

  grub_dl_ref (my_mod);

  data = grub_sfs_mount (file->device->disk);
  if (!data)
    goto fail;

  grub_fshelp_find_file (name, &data->diropen, &fdiro, grub_sfs_iterate_dir,
			 grub_sfs_read_symlink, GRUB_FSHELP_REG);
  if (grub_errno)
    goto fail;

  file->size = fdiro->size;
  data->diropen = *fdiro;
  grub_free (fdiro);

  file->data = data;
  file->offset = 0;

  return 0;

 fail:
  if (data && fdiro != &data->diropen)
    grub_free (fdiro);
  if (data)
    grub_free (data->label);
  grub_free (data);

  grub_dl_unref (my_mod);

  return grub_errno;
}


static grub_err_t
grub_sfs_close (grub_file_t file)
{
  grub_free (file->data);

  grub_dl_unref (my_mod);

  return GRUB_ERR_NONE;
}


/* Read LEN bytes data from FILE into BUF.  */
static grub_ssize_t
grub_sfs_read (grub_file_t file, char *buf, grub_size_t len)
{
  struct grub_sfs_data *data = (struct grub_sfs_data *) file->data;

  int size = grub_sfs_read_file (&data->diropen, file->read_hook,
				 file->offset, len, buf);

  return size;
}


static grub_err_t
grub_sfs_dir (grub_device_t device, const char *path,
	       int (*hook) (const char *filename,
			    const struct grub_dirhook_info *info))
{
  struct grub_sfs_data *data = 0;
  struct grub_fshelp_node *fdiro = 0;

  auto int NESTED_FUNC_ATTR iterate (const char *filename,
				     enum grub_fshelp_filetype filetype,
				     grub_fshelp_node_t node);

  int NESTED_FUNC_ATTR iterate (const char *filename,
				enum grub_fshelp_filetype filetype,
				grub_fshelp_node_t node)
    {
      struct grub_dirhook_info info;
      grub_memset (&info, 0, sizeof (info));
      info.dir = ((filetype & GRUB_FSHELP_TYPE_MASK) == GRUB_FSHELP_DIR);
      grub_free (node);
      return hook (filename, &info);
    }

  grub_dl_ref (my_mod);

  data = grub_sfs_mount (device->disk);
  if (!data)
    goto fail;

  grub_fshelp_find_file (path, &data->diropen, &fdiro, grub_sfs_iterate_dir,
			grub_sfs_read_symlink, GRUB_FSHELP_DIR);
  if (grub_errno)
    goto fail;

  grub_sfs_iterate_dir (fdiro, iterate);

 fail:
  if (data && fdiro != &data->diropen)
    grub_free (fdiro);
  if (data)
    grub_free (data->label);
  grub_free (data);

  grub_dl_unref (my_mod);

  return grub_errno;
}


static grub_err_t
grub_sfs_label (grub_device_t device, char **label)
{
  struct grub_sfs_data *data;
  grub_disk_t disk = device->disk;

  data = grub_sfs_mount (disk);
  if (data)
    *label = data->label;

  grub_free (data);

  return grub_errno;
}

\f
static struct grub_fs grub_sfs_fs =
  {
    .name = "sfs",
    .dir = grub_sfs_dir,
    .open = grub_sfs_open,
    .read = grub_sfs_read,
    .close = grub_sfs_close,
    .label = grub_sfs_label,
    .next = 0
  };

GRUB_MOD_INIT(sfs)
{
  grub_fs_register (&grub_sfs_fs);
  my_mod = mod;
}

GRUB_MOD_FINI(sfs)
{
  grub_fs_unregister (&grub_sfs_fs);
}
Commit	Line	Data
9a909877	1	/* sfs.c - Amiga Smart FileSystem. */
	2	/*
	3	* GRUB -- GRand Unified Bootloader
21cf716a	4	* Copyright (C) 2005,2006,2007,2008 Free Software Foundation, Inc.
9a909877	5	*
5a79f472	6	* GRUB is free software: you can redistribute it and/or modify
9a909877	7	* it under the terms of the GNU General Public License as published by
5a79f472	8	* the Free Software Foundation, either version 3 of the License, or
9a909877	9	* (at your option) any later version.
9a909877	10	*
5a79f472	11	* GRUB is distributed in the hope that it will be useful,
9a909877	12	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	14	* GNU General Public License for more details.
	15	*
	16	* You should have received a copy of the GNU General Public License
5a79f472	17	* along with GRUB. If not, see <http://www.gnu.org/licenses/>.
9a909877	18	*/
	19
	20	#include <grub/err.h>
	21	#include <grub/file.h>
	22	#include <grub/mm.h>
	23	#include <grub/misc.h>
	24	#include <grub/disk.h>
	25	#include <grub/dl.h>
	26	#include <grub/types.h>
	27	#include <grub/fshelp.h>
	28
	29	/* The common header for a block. */
	30	struct grub_sfs_bheader
	31	{
	32	grub_uint8_t magic[4];
	33	grub_uint32_t chksum;
	34	grub_uint32_t ipointtomyself;
	35	} __attribute__ ((packed));
	36
	37	/* The sfs rootblock. */
	38	struct grub_sfs_rblock
	39	{
	40	struct grub_sfs_bheader header;
	41	grub_uint32_t version;
	42	grub_uint8_t unused1[36];
	43	grub_uint32_t blocksize;
	44	grub_uint8_t unused2[40];
	45	grub_uint8_t unused3[8];
	46	grub_uint32_t rootobject;
	47	grub_uint32_t btree;
	48	} __attribute__ ((packed));
	49
	50	/* A SFS object container. */
	51	struct grub_sfs_obj
	52	{
	53	grub_uint8_t unused1[4];
	54	grub_uint32_t nodeid;
	55	grub_uint8_t unused2[4];
	56	union
	57	{
	58	struct
	59	{
	60	grub_uint32_t first_block;
	61	grub_uint32_t size;
	62	} file __attribute__ ((packed));
	63	struct
	64	{
	65	grub_uint32_t hashtable;
	66	grub_uint32_t dir_objc;
	67	} dir __attribute__ ((packed));
	68	} file_dir;
	69	grub_uint8_t unused3[4];
	70	grub_uint8_t type;
	71	grub_uint8_t filename[1];
	72	grub_uint8_t comment[1];
	73	} __attribute__ ((packed));
	74
	75	#define GRUB_SFS_TYPE_DELETED 32
	76	#define GRUB_SFS_TYPE_SYMLINK 64
	77	#define GRUB_SFS_TYPE_DIR 128
	78
	79	/* A SFS object container. */
	80	struct grub_sfs_objc
	81	{
82	struct grub_sfs_bheader header;
83	grub_uint32_t parent;
84	grub_uint32_t next;
85	grub_uint32_t prev;
86	/* The amount of objects depends on the blocksize. */
87	struct grub_sfs_obj objects[1];
88	} __attribute__ ((packed));
89
90	struct grub_sfs_btree_node
91	{
92	grub_uint32_t key;
93	grub_uint32_t data;
94	} __attribute__ ((packed));
95
96	struct grub_sfs_btree_extent
97	{
98	grub_uint32_t key;
99	grub_uint32_t next;
100	grub_uint32_t prev;
101	grub_uint16_t size;
102	} __attribute__ ((packed));
103
104	struct grub_sfs_btree
105	{
106	struct grub_sfs_bheader header;
107	grub_uint16_t nodes;
108	grub_uint8_t leaf;
109	grub_uint8_t nodesize;
110	/* Normally this can be kind of node, but just extents are
111	supported. */
112	struct grub_sfs_btree_node node[1];
113	} __attribute__ ((packed));
114
115	\f
116
117	struct grub_fshelp_node
118	{
119	struct grub_sfs_data *data;
120	int block;
121	int size;
122	};
123
124	/* Information about a "mounted" sfs filesystem. */
125	struct grub_sfs_data
126	{
127	struct grub_sfs_rblock rblock;
128	struct grub_fshelp_node diropen;
129	grub_disk_t disk;
130
131	/* Blocksize in sectors. */
132	unsigned int blocksize;
133
134	/* Label of the filesystem. */
135	char *label;
136	};
137
9a909877	138	static grub_dl_t my_mod;
9a909877	139
	140	\f
	141	/* Lookup the extent starting with BLOCK in the filesystem described
	142	by DATA. Return the extent size in SIZE and the following extent
	143	in NEXTEXT. */
	144	static grub_err_t
	145	grub_sfs_read_extent (struct grub_sfs_data *data, unsigned int block,
	146	int size, int nextext)
	147	{
	148	char *treeblock;
	149	struct grub_sfs_btree *tree;
	150	int i;
	151	int next;
	152	int prev;
	153
	154	treeblock = grub_malloc (data->blocksize);
	155	if (!block)
	156	return 0;
	157
	158	next = grub_be_to_cpu32 (data->rblock.btree);
	159	tree = (struct grub_sfs_btree *) treeblock;
	160
	161	/* Handle this level in the btree. */
	162	do
	163	{
	164	prev = 0;
	165
	166	grub_disk_read (data->disk, next, 0, data->blocksize, treeblock);
	167	if (grub_errno)
	168	{
	169	grub_free (treeblock);
	170	return grub_errno;
	171	}
	172
34519c3f	173	for (i = grub_be_to_cpu16 (tree->nodes) - 1; i >= 0; i--)
9a909877	174	{
	175
	176	#define EXTNODE(tree, index) \
	177	((struct grub_sfs_btree_node ) (((char ) &(tree)->node[0]) \
	178	+ (index) * (tree)->nodesize))
	179
	180	/* Follow the tree down to the leaf level. */
34519c3f	181	if ((grub_be_to_cpu32 (EXTNODE(tree, i)->key) <= block)
9a909877	182	&& !tree->leaf)
9a909877	183	{
	184	next = grub_be_to_cpu32 (EXTNODE (tree, i)->data);
	185	break;
	186	}
	187
	188	/* If the leaf level is reached, just find the correct extent. */
	189	if (grub_be_to_cpu32 (EXTNODE (tree, i)->key) == block && tree->leaf)
	190	{
	191	struct grub_sfs_btree_extent *extent;
	192	extent = (struct grub_sfs_btree_extent *) EXTNODE (tree, i);
	193
	194	/* We found a correct leaf. */
	195	*size = grub_be_to_cpu16 (extent->size);
	196	*nextext = grub_be_to_cpu32 (extent->next);
b39f9d20	197
9a909877	198	grub_free (treeblock);
	199	return 0;
	200	}
	201
	202	#undef EXTNODE
	203
	204	}
	205	} while (!tree->leaf);
	206
	207	grub_free (treeblock);
	208
	209	return grub_error (GRUB_ERR_FILE_READ_ERROR, "SFS extent not found");
	210	}
	211
887d2619	212	static grub_disk_addr_t
887d2619	213	grub_sfs_read_block (grub_fshelp_node_t node, grub_disk_addr_t fileblock)
9a909877	214	{
	215	int blk = node->block;
	216	int size = 0;
	217	int next = 0;
	218
	219	while (blk)
	220	{
	221	grub_err_t err;
	222
	223	/* In case of the first block we don't have to lookup the
	224	extent, the minimum size is always 1. */
	225	if (fileblock == 0)
	226	return blk;
	227
	228	err = grub_sfs_read_extent (node->data, blk, &size, &next);
	229	if (err)
	230	return 0;
	231
887d2619	232	if (fileblock < (unsigned int) size)
9a909877	233	return fileblock + blk;
	234
	235	fileblock -= size;
	236
	237	blk = next;
	238	}
	239
	240	grub_error (GRUB_ERR_FILE_READ_ERROR,
	241	"reading a SFS block outside the extent");
	242
	243	return 0;
	244	}
	245
	246
	247	/* Read LEN bytes from the file described by DATA starting with byte
	248	POS. Return the amount of read bytes in READ. */
	249	static grub_ssize_t
	250	grub_sfs_read_file (grub_fshelp_node_t node,
9959f7db	251	void NESTED_FUNC_ATTR (*read_hook) (grub_disk_addr_t sector,
9a909877	252	unsigned offset, unsigned length),
524a1e6a	253	int pos, grub_size_t len, char *buf)
9a909877	254	{
	255	return grub_fshelp_read_file (node->data->disk, node, read_hook,
	256	pos, len, buf, grub_sfs_read_block,
	257	node->size, 0);
	258	}
	259
	260
	261	static struct grub_sfs_data *
	262	grub_sfs_mount (grub_disk_t disk)
	263	{
	264	struct grub_sfs_data *data;
	265	struct grub_sfs_objc *rootobjc;
	266	char *rootobjc_data = 0;
	267	unsigned int blk;
	268
	269	data = grub_malloc (sizeof (*data));
	270	if (!data)
	271	return 0;
	272
	273	/* Read the rootblock. */
	274	grub_disk_read (disk, 0, 0, sizeof (struct grub_sfs_rblock),
238e871f	275	&data->rblock);
9a909877	276	if (grub_errno)
	277	goto fail;
	278
	279	/* Make sure this is a sfs filesystem. */
7b455f4d	280	if (grub_strncmp ((char *) (data->rblock.header.magic), "SFS", 4))
9a909877	281	{
	282	grub_error (GRUB_ERR_BAD_FS, "not a sfs filesystem");
	283	goto fail;
	284	}
	285
	286	data->blocksize = grub_be_to_cpu32 (data->rblock.blocksize);
	287	rootobjc_data = grub_malloc (data->blocksize);
7b455f4d	288	if (! rootobjc_data)
9a909877	289	goto fail;
	290
	291	/* Read the root object container. */
	292	grub_disk_read (disk, grub_be_to_cpu32 (data->rblock.rootobject), 0,
	293	data->blocksize, rootobjc_data);
	294	if (grub_errno)
	295	goto fail;
	296
	297	rootobjc = (struct grub_sfs_objc *) rootobjc_data;
	298
	299	blk = grub_be_to_cpu32 (rootobjc->objects[0].file_dir.dir.dir_objc);
	300	data->diropen.size = 0;
	301	data->diropen.block = blk;
	302	data->diropen.data = data;
	303	data->disk = disk;
7b455f4d	304	data->label = grub_strdup ((char *) (rootobjc->objects[0].filename));
9a909877	305
	306	return data;
	307
	308	fail:
0a203f83	309	if (grub_errno == GRUB_ERR_OUT_OF_RANGE)
	310	grub_error (GRUB_ERR_BAD_FS, "not an sfs filesystem");
	311
9a909877	312	grub_free (data);
	313	grub_free (rootobjc_data);
	314	return 0;
	315	}
	316
	317
	318	static char *
	319	grub_sfs_read_symlink (grub_fshelp_node_t node)
	320	{
	321	struct grub_sfs_data *data = node->data;
	322	char *symlink;
	323	char *block;
	324
	325	block = grub_malloc (data->blocksize);
	326	if (!block)
	327	return 0;
	328
	329	grub_disk_read (data->disk, node->block, 0, data->blocksize, block);
	330	if (grub_errno)
	331	{
	332	grub_free (block);
	333	return 0;
	334	}
	335
	336	/* This is just a wild guess, but it always worked for me. How the
	337	SLNK block looks like is not documented in the SFS docs. */
	338	symlink = grub_strdup (&block[24]);
	339	grub_free (block);
	340	if (!symlink)
	341	return 0;
	342
	343	return symlink;
	344	}
	345
	346	static int
	347	grub_sfs_iterate_dir (grub_fshelp_node_t dir,
	348	int NESTED_FUNC_ATTR
	349	(hook) (const char filename,
	350	enum grub_fshelp_filetype filetype,
	351	grub_fshelp_node_t node))
	352	{
	353	struct grub_fshelp_node *node = 0;
	354	struct grub_sfs_data *data = dir->data;
	355	char *objc_data;
	356	struct grub_sfs_objc *objc;
	357	unsigned int next = dir->block;
	358	int pos;
	359
	360	auto int NESTED_FUNC_ATTR grub_sfs_create_node (const char *name, int block,
	361	int size, int type);
	362
	363	int NESTED_FUNC_ATTR grub_sfs_create_node (const char *name, int block,
	364	int size, int type)
	365	{
	366	node = grub_malloc (sizeof (*node));
	367	if (!node)
	368	return 1;
	369
	370	node->data = data;
	371	node->size = size;
	372	node->block = block;
b39f9d20	373
9a909877	374	return hook (name, type, node);
	375	}
	376
	377	objc_data = grub_malloc (data->blocksize);
	378	if (!objc_data)
	379	goto fail;
	380
	381	/* The Object container can consist of multiple blocks, iterate over
	382	every block. */
	383	while (next)
	384	{
	385	grub_disk_read (data->disk, next, 0, data->blocksize, objc_data);
	386	if (grub_errno)
	387	goto fail;
	388
	389	objc = (struct grub_sfs_objc *) objc_data;
	390
	391	pos = (char ) &objc->objects[0] - (char ) objc;
	392
	393	/* Iterate over all entries in this block. */
	394	while (pos + sizeof (struct grub_sfs_obj) < data->blocksize)
	395	{
	396	struct grub_sfs_obj *obj;
	397	obj = (struct grub_sfs_obj ) ((char ) objc + pos);
7b455f4d	398	char filename = (char ) (obj->filename);
9a909877	399	int len;
	400	enum grub_fshelp_filetype type;
	401	unsigned int block;
	402
	403	/* The filename and comment dynamically increase the size of
	404	the object. */
	405	len = grub_strlen (filename);
	406	len += grub_strlen (filename + len + 1);
	407
	408	pos += sizeof (*obj) + len;
	409	/* Round up to a multiple of two bytes. */
	410	pos = ((pos + 1) >> 1) << 1;
	411
	412	if (grub_strlen (filename) == 0)
	413	continue;
	414
	415	/* First check if the file was not deleted. */
	416	if (obj->type & GRUB_SFS_TYPE_DELETED)
	417	continue;
	418	else if (obj->type & GRUB_SFS_TYPE_SYMLINK)
	419	type = GRUB_FSHELP_SYMLINK;
	420	else if (obj->type & GRUB_SFS_TYPE_DIR)
	421	type = GRUB_FSHELP_DIR;
	422	else
	423	type = GRUB_FSHELP_REG;
	424
	425	if (type == GRUB_FSHELP_DIR)
	426	block = grub_be_to_cpu32 (obj->file_dir.dir.dir_objc);
	427	else
	428	block = grub_be_to_cpu32 (obj->file_dir.file.first_block);
	429
	430	if (grub_sfs_create_node (filename, block,
	431	grub_be_to_cpu32 (obj->file_dir.file.size),
	432	type))
	433	{
	434	grub_free (objc_data);
	435	return 1;
	436	}
	437	}
	438
	439	next = grub_be_to_cpu32 (objc->next);
	440	}
	441
	442	fail:
	443	grub_free (objc_data);
0c5e79ab	444	return 0;
9a909877	445	}
	446
	447
	448	/* Open a file named NAME and initialize FILE. */
	449	static grub_err_t
	450	grub_sfs_open (struct grub_file file, const char name)
	451	{
	452	struct grub_sfs_data *data;
	453	struct grub_fshelp_node *fdiro = 0;
b39f9d20	454
9a909877	455	grub_dl_ref (my_mod);
b39f9d20	456
9a909877	457	data = grub_sfs_mount (file->device->disk);
	458	if (!data)
	459	goto fail;
b39f9d20	460
9a909877	461	grub_fshelp_find_file (name, &data->diropen, &fdiro, grub_sfs_iterate_dir,
	462	grub_sfs_read_symlink, GRUB_FSHELP_REG);
	463	if (grub_errno)
	464	goto fail;
b39f9d20	465
9a909877	466	file->size = fdiro->size;
	467	data->diropen = *fdiro;
	468	grub_free (fdiro);
	469
	470	file->data = data;
	471	file->offset = 0;
	472
	473	return 0;
	474
	475	fail:
	476	if (data && fdiro != &data->diropen)
	477	grub_free (fdiro);
bb34586c	478	if (data)
bb34586c	479	grub_free (data->label);
9a909877	480	grub_free (data);
b39f9d20	481
9a909877	482	grub_dl_unref (my_mod);
9a909877	483
	484	return grub_errno;
	485	}
	486
	487
	488	static grub_err_t
	489	grub_sfs_close (grub_file_t file)
	490	{
	491	grub_free (file->data);
	492
9a909877	493	grub_dl_unref (my_mod);
9a909877	494
	495	return GRUB_ERR_NONE;
	496	}
	497
	498
	499	/* Read LEN bytes data from FILE into BUF. */
	500	static grub_ssize_t
524a1e6a	501	grub_sfs_read (grub_file_t file, char *buf, grub_size_t len)
9a909877	502	{
	503	struct grub_sfs_data data = (struct grub_sfs_data ) file->data;
	504
	505	int size = grub_sfs_read_file (&data->diropen, file->read_hook,
	506	file->offset, len, buf);
	507
	508	return size;
	509	}
	510
	511
	512	static grub_err_t
b39f9d20	513	grub_sfs_dir (grub_device_t device, const char *path,
b39f9d20	514	int (hook) (const char filename,
05aaebfb	515	const struct grub_dirhook_info *info))
9a909877	516	{
	517	struct grub_sfs_data *data = 0;
	518	struct grub_fshelp_node *fdiro = 0;
b39f9d20	519
9a909877	520	auto int NESTED_FUNC_ATTR iterate (const char *filename,
	521	enum grub_fshelp_filetype filetype,
	522	grub_fshelp_node_t node);
	523
	524	int NESTED_FUNC_ATTR iterate (const char *filename,
	525	enum grub_fshelp_filetype filetype,
	526	grub_fshelp_node_t node)
	527	{
05aaebfb	528	struct grub_dirhook_info info;
	529	grub_memset (&info, 0, sizeof (info));
	530	info.dir = ((filetype & GRUB_FSHELP_TYPE_MASK) == GRUB_FSHELP_DIR);
9a909877	531	grub_free (node);
05aaebfb	532	return hook (filename, &info);
9a909877	533	}
9a909877	534
9a909877	535	grub_dl_ref (my_mod);
b39f9d20	536
9a909877	537	data = grub_sfs_mount (device->disk);
	538	if (!data)
	539	goto fail;
	540
	541	grub_fshelp_find_file (path, &data->diropen, &fdiro, grub_sfs_iterate_dir,
	542	grub_sfs_read_symlink, GRUB_FSHELP_DIR);
	543	if (grub_errno)
	544	goto fail;
	545
	546	grub_sfs_iterate_dir (fdiro, iterate);
b39f9d20	547
9a909877	548	fail:
	549	if (data && fdiro != &data->diropen)
	550	grub_free (fdiro);
bb34586c	551	if (data)
bb34586c	552	grub_free (data->label);
9a909877	553	grub_free (data);
9a909877	554
9a909877	555	grub_dl_unref (my_mod);
9a909877	556
	557	return grub_errno;
	558	}
	559
	560
	561	static grub_err_t
	562	grub_sfs_label (grub_device_t device, char **label)
	563	{
	564	struct grub_sfs_data *data;
	565	grub_disk_t disk = device->disk;
	566
	567	data = grub_sfs_mount (disk);
	568	if (data)
	569	*label = data->label;
	570
	571	grub_free (data);
	572
	573	return grub_errno;
	574	}
	575
	576	\f
	577	static struct grub_fs grub_sfs_fs =
	578	{
	579	.name = "sfs",
	580	.dir = grub_sfs_dir,
	581	.open = grub_sfs_open,
	582	.read = grub_sfs_read,
	583	.close = grub_sfs_close,
	584	.label = grub_sfs_label,
	585	.next = 0
	586	};
	587
6d099807	588	GRUB_MOD_INIT(sfs)
9a909877	589	{
	590	grub_fs_register (&grub_sfs_fs);
	591	my_mod = mod;
	592	}
	593
6d099807	594	GRUB_MOD_FINI(sfs)
9a909877	595	{
	596	grub_fs_unregister (&grub_sfs_fs);
	597	}