Allow referencing a filesystem by a file it contains
From: Pavel Roskin
ChangeLog:
* conf/common.rmk: Add fs_file.mod.
* disk/fs_file.c: New file.
* include/grub/disk.h (enum grub_disk_dev_id): Add
GRUB_DISK_DEVICE_FILE_ID.
---
conf/common.rmk | 9 +++
disk/fs_file.c | 136 +++++++++++++++++++++++++++++++++++++++++++++++++++
include/grub/disk.h | 1
3 files changed, 144 insertions(+), 2 deletions(-)
create mode 100644 disk/fs_file.c
diff --git a/conf/common.rmk b/conf/common.rmk
index d0c142b..fbca2e4 100644
--- a/conf/common.rmk
+++ b/conf/common.rmk
@@ -349,8 +349,8 @@ scsi_mod_LDFLAGS = $(COMMON_LDFLAGS)
# Commands.
pkglib_MODULES += minicmd.mod extcmd.mod hello.mod handler.mod \
- ls.mod cmp.mod cat.mod help.mod search.mod \
- loopback.mod fs_uuid.mod configfile.mod echo.mod \
+ ls.mod cmp.mod cat.mod help.mod search.mod loopback.mod \
+ fs_file.mod fs_uuid.mod configfile.mod echo.mod \
terminfo.mod test.mod blocklist.mod hexdump.mod \
read.mod sleep.mod loadenv.mod crc.mod parttool.mod \
pcpart.mod memrw.mod normal.mod sh.mod lua.mod \
@@ -431,6 +431,11 @@ loopback_mod_SOURCES = disk/loopback.c
loopback_mod_CFLAGS = $(COMMON_CFLAGS)
loopback_mod_LDFLAGS = $(COMMON_LDFLAGS)
+# For fs_file.mod
+fs_file_mod_SOURCES = disk/fs_file.c
+fs_file_mod_CFLAGS = $(COMMON_CFLAGS)
+fs_file_mod_LDFLAGS = $(COMMON_LDFLAGS)
+
# For fs_uuid.mod
fs_uuid_mod_SOURCES = disk/fs_uuid.c
fs_uuid_mod_CFLAGS = $(COMMON_CFLAGS)
diff --git a/disk/fs_file.c b/disk/fs_file.c
new file mode 100644
index 0000000..d81a971
--- /dev/null
+++ b/disk/fs_file.c
@@ -0,0 +1,136 @@
+/* fs_file.c - Access partition by a file it contains. */
+/*
+ * GRUB -- GRand Unified Bootloader
+ * Copyright (C) 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 .
+ */
+
+#include
+#include
+#include
+#include
+#include
+#include
+
+static grub_device_t
+search_fs_file (const char *key, unsigned long *count)
+{
+ char *filename = NULL;
+ grub_device_t ret = NULL;
+ *count = 0;
+
+ auto int iterate_device (const char *name);
+ int iterate_device (const char *name)
+ {
+ int len;
+ grub_file_t file;
+
+ (*count)++;
+
+ len = grub_strlen (name) + 2 + grub_strlen (key) + 1;
+ filename = grub_realloc (filename, len);
+ if (! filename)
+ return 1;
+
+ grub_sprintf (filename, "(%s)%s", name, key);
+ file = grub_file_open (filename);
+ if (file)
+ {
+ grub_file_close (file);
+ ret = grub_device_open (name);
+ return 1;
+ }
+
+ grub_errno = GRUB_ERR_NONE;
+ return 0;
+ }
+
+ grub_device_iterate (iterate_device);
+ grub_free (filename);
+
+ return ret;
+}
+
+static grub_err_t
+grub_fs_file_open (const char *name, grub_disk_t disk)
+{
+ grub_device_t dev;
+
+ if (grub_strncmp (name, "FILE=", sizeof ("FILE=") - 1))
+ return grub_error (GRUB_ERR_UNKNOWN_DEVICE, "not a FILE virtual volume");
+
+ dev = search_fs_file (name + sizeof ("FILE=") - 1, &disk->id);
+ if (! dev)
+ return grub_error (GRUB_ERR_UNKNOWN_DEVICE, "no matching file found");
+
+ disk->total_sectors = dev->disk->total_sectors;
+ disk->has_partitions = 0;
+ if (dev->disk->partition)
+ {
+ disk->partition = grub_malloc (sizeof (*disk->partition));
+ if (disk->partition)
+ grub_memcpy (disk->partition, dev->disk->partition,
+ sizeof (*disk->partition));
+ }
+ else
+ disk->partition = NULL;
+
+ disk->data = dev;
+
+ return GRUB_ERR_NONE;
+}
+
+static void
+grub_fs_file_close (grub_disk_t disk)
+{
+ grub_device_t parent = disk->data;
+ grub_device_close (parent);
+}
+
+static grub_err_t
+grub_fs_file_read (grub_disk_t disk, grub_disk_addr_t sector,
+ grub_size_t size, char *buf)
+{
+ grub_device_t parent = disk->data;
+ return parent->disk->dev->read (parent->disk, sector, size, buf);
+}
+
+static grub_err_t
+grub_fs_file_write (grub_disk_t disk, grub_disk_addr_t sector,
+ grub_size_t size, const char *buf)
+{
+ grub_device_t parent = disk->data;
+ return parent->disk->dev->write (parent->disk, sector, size, buf);
+}
+
+static struct grub_disk_dev grub_fs_file_dev = {
+ .name = "fs_file",
+ .id = GRUB_DISK_DEVICE_FILE_ID,
+ .open = grub_fs_file_open,
+ .close = grub_fs_file_close,
+ .read = grub_fs_file_read,
+ .write = grub_fs_file_write,
+ .next = 0
+};
+
+GRUB_MOD_INIT (fs_file)
+{
+ grub_disk_dev_register (&grub_fs_file_dev);
+}
+
+GRUB_MOD_FINI (fs_file)
+{
+ grub_disk_dev_unregister (&grub_fs_file_dev);
+}
diff --git a/include/grub/disk.h b/include/grub/disk.h
index a0cc642..1f96111 100644
--- a/include/grub/disk.h
+++ b/include/grub/disk.h
@@ -38,6 +38,7 @@ enum grub_disk_dev_id
GRUB_DISK_DEVICE_ATA_ID,
GRUB_DISK_DEVICE_MEMDISK_ID,
GRUB_DISK_DEVICE_NAND_ID,
+ GRUB_DISK_DEVICE_FILE_ID,
GRUB_DISK_DEVICE_UUID_ID,
GRUB_DISK_DEVICE_PXE_ID,
GRUB_DISK_DEVICE_SCSI_ID,