automake commit without merge history

grub-core/kern/fs.c

@@ -0,0 +1,261 @@
+/* fs.c - filesystem manager */
+/*
+ *  GRUB  --  GRand Unified Bootloader
+ *  Copyright (C) 2002,2005,2007  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/disk.h>
+#include <grub/net.h>
+#include <grub/fs.h>
+#include <grub/file.h>
+#include <grub/err.h>
+#include <grub/misc.h>
+#include <grub/types.h>
+#include <grub/mm.h>
+#include <grub/term.h>
+
+static grub_fs_t grub_fs_list;
+
+grub_fs_autoload_hook_t grub_fs_autoload_hook = 0;
+
+void
+grub_fs_register (grub_fs_t fs)
+{
+  fs->next = grub_fs_list;
+  grub_fs_list = fs;
+}
+
+void
+grub_fs_unregister (grub_fs_t fs)
+{
+  grub_fs_t *p, q;
+
+  for (p = &grub_fs_list, q = *p; q; p = &(q->next), q = q->next)
+    if (q == fs)
+      {
+	*p = q->next;
+	break;
+      }
+}
+
+void
+grub_fs_iterate (int (*hook) (const grub_fs_t fs))
+{
+  grub_fs_t p;
+
+  for (p = grub_fs_list; p; p = p->next)
+    if (hook (p))
+      break;
+}
+
+grub_fs_t
+grub_fs_probe (grub_device_t device)
+{
+  grub_fs_t p;
+  auto int dummy_func (const char *filename,
+		       const struct grub_dirhook_info *info);
+
+  int dummy_func (const char *filename __attribute__ ((unused)),
+		  const struct grub_dirhook_info *info  __attribute__ ((unused)))
+    {
+      return 1;
+    }
+
+  if (device->disk)
+    {
+      /* Make it sure not to have an infinite recursive calls.  */
+      static int count = 0;
+
+      for (p = grub_fs_list; p; p = p->next)
+	{
+	  grub_dprintf ("fs", "Detecting %s...\n", p->name);
+	  (p->dir) (device, "/", dummy_func);
+	  if (grub_errno == GRUB_ERR_NONE)
+	    return p;
+
+	  grub_error_push ();
+	  grub_dprintf ("fs", "%s detection failed.\n", p->name);
+	  grub_error_pop ();
+
+	  if (grub_errno != GRUB_ERR_BAD_FS)
+	    return 0;
+
+	  grub_errno = GRUB_ERR_NONE;
+	}
+
+      /* Let's load modules automatically.  */
+      if (grub_fs_autoload_hook && count == 0)
+	{
+	  count++;
+
+	  while (grub_fs_autoload_hook ())
+	    {
+	      p = grub_fs_list;
+
+	      (p->dir) (device, "/", dummy_func);
+	      if (grub_errno == GRUB_ERR_NONE)
+		{
+		  count--;
+		  return p;
+		}
+
+	      if (grub_errno != GRUB_ERR_BAD_FS)
+		{
+		  count--;
+		  return 0;
+		}
+
+	      grub_errno = GRUB_ERR_NONE;
+	    }
+
+	  count--;
+	}
+    }
+  else if (device->net->fs)
+    return device->net->fs;
+
+  grub_error (GRUB_ERR_UNKNOWN_FS, "unknown filesystem");
+  return 0;
+}
+
+
+
+/* Block list support routines.  */
+
+struct grub_fs_block
+{
+  grub_disk_addr_t offset;
+  unsigned long length;
+};
+
+static grub_err_t
+grub_fs_blocklist_open (grub_file_t file, const char *name)
+{
+  char *p = (char *) name;
+  unsigned num = 0;
+  unsigned i;
+  grub_disk_t disk = file->device->disk;
+  struct grub_fs_block *blocks;
+
+  /* First, count the number of blocks.  */
+  do
+    {
+      num++;
+      p = grub_strchr (p, ',');
+      if (p)
+	p++;
+    }
+  while (p);
+
+  /* Allocate a block list.  */
+  blocks = grub_zalloc (sizeof (struct grub_fs_block) * (num + 1));
+  if (! blocks)
+    return 0;
+
+  file->size = 0;
+  p = (char *) name;
+  for (i = 0; i < num; i++)
+    {
+      if (*p != '+')
+	{
+	  blocks[i].offset = grub_strtoull (p, &p, 0);
+	  if (grub_errno != GRUB_ERR_NONE || *p != '+')
+	    {
+	      grub_error (GRUB_ERR_BAD_FILENAME,
+			  "invalid file name `%s'", name);
+	      goto fail;
+	    }
+	}
+
+      p++;
+      blocks[i].length = grub_strtoul (p, &p, 0);
+      if (grub_errno != GRUB_ERR_NONE
+	  || blocks[i].length == 0
+	  || (*p && *p != ',' && ! grub_isspace (*p)))
+	{
+	  grub_error (GRUB_ERR_BAD_FILENAME,
+		      "invalid file name `%s'", name);
+	  goto fail;
+	}
+
+      if (disk->total_sectors < blocks[i].offset + blocks[i].length)
+	{
+	  grub_error (GRUB_ERR_BAD_FILENAME, "beyond the total sectors");
+	  goto fail;
+	}
+
+      file->size += (blocks[i].length << GRUB_DISK_SECTOR_BITS);
+      p++;
+    }
+
+  file->data = blocks;
+
+  return GRUB_ERR_NONE;
+
+ fail:
+  grub_free (blocks);
+  return grub_errno;
+}
+
+static grub_ssize_t
+grub_fs_blocklist_read (grub_file_t file, char *buf, grub_size_t len)
+{
+  struct grub_fs_block *p;
+  grub_disk_addr_t sector;
+  grub_off_t offset;
+  grub_ssize_t ret = 0;
+
+  if (len > file->size - file->offset)
+    len = file->size - file->offset;
+
+  sector = (file->offset >> GRUB_DISK_SECTOR_BITS);
+  offset = (file->offset & (GRUB_DISK_SECTOR_SIZE - 1));
+  for (p = file->data; p->length && len > 0; p++)
+    {
+      if (sector < p->length)
+	{
+	  grub_size_t size;
+
+	  size = len;
+	  if (((size + offset + GRUB_DISK_SECTOR_SIZE - 1)
+	       >> GRUB_DISK_SECTOR_BITS) > p->length - sector)
+	    size = ((p->length - sector) << GRUB_DISK_SECTOR_BITS) - offset;
+
+	  if (grub_disk_read (file->device->disk, p->offset + sector, offset,
+			      size, buf) != GRUB_ERR_NONE)
+	    return -1;
+
+	  ret += size;
+	  len -= size;
+	  sector -= ((size + offset) >> GRUB_DISK_SECTOR_BITS);
+	  offset = ((size + offset) & (GRUB_DISK_SECTOR_SIZE - 1));
+	}
+      else
+	sector -= p->length;
+    }
+
+  return ret;
+}
+
+struct grub_fs grub_fs_blocklist =
+  {
+    .name = "blocklist",
+    .dir = 0,
+    .open = grub_fs_blocklist_open,
+    .read = grub_fs_blocklist_read,
+    .close = 0,
+    .next = 0
+  };