The purpose we implement xattr is storing passive translator in a
more general way. Now passive translator record now can be stored
using extended attributes. The new diskfs_{get,set}_translator()
functions are also compatibility with the "legacy" passive translator
record.
Thanks for antrik's suggestions.
--
Best regards,
Shengyu Zhang.
---
ext2fs/inode.c | 156 +++++++++++++++++++++++++++++----------------------------
1 file changed, 80 insertions(+), 76 deletions(-)
diff --git a/ext2fs/inode.c b/ext2fs/inode.c
index ccc8d69..be163d5 100644
--- a/ext2fs/inode.c
+++ b/ext2fs/inode.c
@@ -26,6 +26,7 @@
#include <sys/stat.h>
#include <sys/statfs.h>
#include <sys/statvfs.h>
+#include <sys/xattr.h>
/* these flags aren't actually defined by a header file yet, so temporarily
disable them if necessary. */
@@ -540,81 +541,62 @@ error_t
diskfs_set_translator (struct node *np, const char *name, unsigned namelen,
struct protid *cred)
{
- daddr_t blkno;
+ int len;
error_t err;
- char buf[block_size];
- struct ext2_inode *di;
assert (!diskfs_readonly);
- if (sblock->s_creator_os != EXT2_OS_HURD)
- return EOPNOTSUPP;
-
- if (namelen + 2 > block_size)
- return ENAMETOOLONG;
-
err = diskfs_catch_exception ();
if (err)
return err;
- di = dino_ref (np->cache_id);
- blkno = di->i_translator;
-
- if (namelen && !blkno)
+ /* If a old translator record found, clear it */
+ if (sblock->s_creator_os == EXT2_OS_HURD)
{
- /* Allocate block for translator */
- blkno =
- ext2_new_block ((diskfs_node_disknode (np)->info.i_block_group
- * EXT2_BLOCKS_PER_GROUP (sblock))
- + sblock->s_first_data_block,
- 0, 0, 0);
- if (blkno == 0)
+ daddr_t blkno;
+ struct ext2_inode *di;
+
+ di = dino_ref (np->cache_id);
+ blkno = di->i_translator;
+
+ if (blkno)
{
- dino_deref (di);
- diskfs_end_catch_exception ();
- return ENOSPC;
- }
+ ext2_warning("Old tranlator record found, clear it");
- di->i_translator = blkno;
- diskfs_node_disknode (np)->info_i_translator = blkno;
- record_global_poke (di);
+ /* Clear block for translator going away. */
+ di->i_translator = 0;
+ diskfs_node_disknode (np)->info_i_translator = 0;
+ record_global_poke (di);
+ ext2_free_blocks (blkno, 1);
- np->dn_stat.st_blocks += 1 << log2_stat_blocks_per_fs_block;
- np->dn_set_ctime = 1;
- }
- else if (!namelen && blkno)
- {
- /* Clear block for translator going away. */
- di->i_translator = 0;
- diskfs_node_disknode (np)->info_i_translator = 0;
- record_global_poke (di);
- ext2_free_blocks (blkno, 1);
-
- np->dn_stat.st_blocks -= 1 << log2_stat_blocks_per_fs_block;
- np->dn_stat.st_mode &= ~S_IPTRANS;
- np->dn_set_ctime = 1;
+ np->dn_stat.st_blocks -= 1 << log2_stat_blocks_per_fs_block;
+ np->dn_stat.st_mode &= ~S_IPTRANS;
+ np->dn_set_ctime = 1;
+ }
+ else
+ dino_deref (di);
}
- else
- dino_deref (di);
-
- if (namelen)
- {
- void *blkptr;
- buf[0] = namelen & 0xFF;
- buf[1] = (namelen >> 8) & 0xFF;
- memcpy (buf + 2, name, namelen);
+ /* Use xattr to store translator record, with key "gnu.translator" */
+ err = ext2_get_xattr(np, "gnu.translator", NULL, &len);
+ if (err && err != ENODATA)
+ return err;
- blkptr = disk_cache_block_ref (blkno);
- memcpy (blkptr, buf, block_size);
- record_global_poke (blkptr);
+ if (namelen && err == ENODATA)
+ {
+ err = ext2_set_xattr(np, "gnu.translator", name, namelen, XATTR_CREATE);
np->dn_stat.st_mode |= S_IPTRANS;
np->dn_set_ctime = 1;
}
+ else if (!namelen && !err)
+ {
+ err = ext2_set_xattr(np, "gnu.translator", NULL, 0, 0);
+ }
diskfs_end_catch_exception ();
return err;
+
}
/* Implement the diskfs_get_translator callback from the diskfs library.
@@ -623,37 +605,59 @@ error_t
diskfs_get_translator (struct node *np, char **namep, unsigned *namelen)
{
error_t err = 0;
- daddr_t blkno;
- unsigned datalen;
- void *transloc;
- struct ext2_inode *di;
-
- assert (sblock->s_creator_os == EXT2_OS_HURD);
+ int datalen;
err = diskfs_catch_exception ();
if (err)
return err;
- di = dino_ref (np->cache_id);
- blkno = di->i_translator;
- dino_deref (di);
- assert (blkno);
- transloc = disk_cache_block_ref (blkno);
-
- datalen =
- ((unsigned char *)transloc)[0] + (((unsigned char *)transloc)[1] << 8);
- if (datalen > block_size - 2)
- err = EFTYPE; /* ? */
- else
+ /* If a old translator record found, read it firstly */
+ if (sblock->s_creator_os == EXT2_OS_HURD)
{
- *namep = malloc (datalen);
- if (!*namep)
- err = ENOMEM;
- else
- memcpy (*namep, transloc + 2, datalen);
+ daddr_t blkno;
+ void *transloc;
+ struct ext2_inode *di;
+
+ di = dino_ref (np->cache_id);
+ blkno = di->i_translator;
+ dino_deref (di);
+
+ if (blkno)
+ {
+ ext2_warning("This is a old translotor record, please update it");
+
+ transloc = disk_cache_block_ref (blkno);
+ datalen = ((unsigned char *)transloc)[0] +
+ (((unsigned char *)transloc)[1] << 8);
+ if (datalen > block_size - 2)
+ err = EFTYPE; /* ? */
+ else
+ {
+ *namep = malloc (datalen);
+ if (!*namep)
+ err = ENOMEM;
+ else
+ memcpy (*namep, transloc + 2, datalen);
+ }
+
+ disk_cache_block_deref (transloc);
+ diskfs_end_catch_exception ();
+
+ *namelen = datalen;
+ return err;
+ }
}
- disk_cache_block_deref (transloc);
+ err = ext2_get_xattr (np, "gnu.translator", NULL, &datalen);
+ if (err)
+ return err;
+
+ *namep = malloc (datalen);
+ if (!*namep)
+ err = ENOMEM;
+ else
+ err = ext2_get_xattr (np, "gnu.translator", *namep, &datalen);
+
diskfs_end_catch_exception ();
*namelen = datalen;
--
2.9.0
