sergiotarxz/nuttx
sergiotarxz/nuttx
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

Combine hard link traversal into one common function

Browse Source 
git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@918 42af7a65-404d-4744-a932-0658087f49c3
This commit is contained in:
patacongo 2008-09-12 20:54:14 +00:00
parent 031dfef23c
commit 890f1034e0
1 changed files with 90 additions and 90 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

180
fs/romfs/fs_romfsutil.c
View File

@ -188,6 +188,59 @@ static inline int romfs_checkentry(struct romfs_mountpt_s *rm, uint32 offset,
return -ENOENT;
}
/****************************************************************************
* Name: romfs_followhardlinks
*
* Desciption:
* Given the offset to a file header, check if the file is a hardlink.
* If so, traverse the hard links until the terminal, non-linked header
* so found and return that offset.
*
****************************************************************************/
static int romfs_followhardlinks(struct romfs_mountpt_s *rm, uint32 offset,
uint32 *poffset)
{
uint32 sector;
uint32 next;
uint16 ndx;
int ret;
int i;
/* Loop while we are redirected by hardlinks */
for (i = 0; i < ROMF_MAX_LINKS; i++)
{
/* Convert the offset into sector + index */
sector = SEC_NSECTORS(rm, offset);
ndx = offset & SEC_NDXMASK(rm);
/* Read the sector into memory */
ret = romfs_devcacheread(rm, sector);
if (ret < 0)
{
return ret;
}
/* Check if this is a hard link */
next = romfs_devread32(rm, ndx + ROMFS_FHDR_NEXT);
if (!IS_HARDLINK(next))
{
*poffset = offset;
return OK;
}
/* Follow the hard-link */
offset = romfs_devread32(rm, ndx + ROMFS_FHDR_INFO);
}
return -ELOOP;
}
/****************************************************************************
* Name: romfs_searchdir
*
@ -760,76 +813,47 @@ int romfs_parsedirentry(struct romfs_mountpt_s *rm, uint32 offset, uint32 *poffs
uint32 sector;
uint32 save;
uint32 next;
uint32 info;
uint32 size;
uint16 ndx;
int ret;
int i;
/* Loop while we are redirected by hardlinks */
/* Convert the offset into sector + index */
for (i = 0; i < ROMF_MAX_LINKS; i++)
sector = SEC_NSECTORS(rm, offset);
ndx = offset & SEC_NDXMASK(rm);
/* Read the sector into memory */
ret = romfs_devcacheread(rm, sector);
if (ret < 0)
{
/* Convert the offset into sector + index */
sector = SEC_NSECTORS(rm, offset);
ndx = offset & SEC_NDXMASK(rm);
/* Read the sector into memory */
ret = romfs_devcacheread(rm, sector);
if (ret < 0)
{
return ret;
}
/* Because everything is chunked and aligned to 16-bit boundaries,
* we know that most the basic node info fits into the sector. The
* associated name may not, however.
*/
next = romfs_devread32(rm, ndx + ROMFS_FHDR_NEXT);
info = romfs_devread32(rm, ndx + ROMFS_FHDR_INFO);
size = romfs_devread32(rm, ndx + ROMFS_FHDR_SIZE);
/* Is this the first offset we have tried? */
if (i == 0)
{
/* Yes.. Save the first 'next' value. That has the offset needed to
* traverse the parent directory.
*/
save = next;
}
/* Is this a hardlink? */
if (IS_HARDLINK(next))
{
/* Yes.. then the info field is the offset to the actual entry
* that we are interested in.
*/
offset = info;
}
else
{
/* No... then break returning the directory information.
* Retaining the original offset
*/
*poffset = offset;
*pnext = (save & RFNEXT_OFFSETMASK) | (next & RFNEXT_ALLMODEMASK);
*pinfo = info;
*psize = size;
return OK;
}
return ret;
}
/* Too many hard links -- probably an infinite loop */
/* Yes.. Save the first 'next' value. That has the offset needed to
* traverse the parent directory. But we may need to change the type
* after we follow the hard links.
*/
return -ELOOP;
save = romfs_devread32(rm, ndx + ROMFS_FHDR_NEXT);
/* Traverse hardlinks as necesssary to get to the real file header */
ret = romfs_followhardlinks(rm, offset, poffset);
if (ret < 0)
{
return ret;
}
/* Because everything is chunked and aligned to 16-bit boundaries,
* we know that most the basic node info fits into the sector. The
* associated name may not, however.
*/
next = romfs_devread32(rm, ndx + ROMFS_FHDR_NEXT);
*pnext = (save & RFNEXT_OFFSETMASK) | (next & RFNEXT_ALLMODEMASK);
*pinfo = romfs_devread32(rm, ndx + ROMFS_FHDR_INFO);
*psize = romfs_devread32(rm, ndx + ROMFS_FHDR_SIZE);
return OK;
}
/****************************************************************************
@ -917,39 +941,15 @@ int romfs_parsefilename(struct romfs_mountpt_s *rm, uint32 offset, char *pname)
int romfs_datastart(struct romfs_mountpt_s *rm, uint32 offset, uint32 *start)
{
uint32 sector;
uint32 next;
uint32 info;
uint16 ndx;
int ret;
/* Loop while we traverse any hardlinks */
/* Traverse hardlinks as necesssary to get to the real file header */
for (;;)
ret = romfs_followhardlinks(rm, offset, &offset);
if (ret < 0)
{
/* Convert the offset into sector + index */
sector = SEC_NSECTORS(rm, offset);
ndx = offset & SEC_NDXMASK(rm);
/* Read the sector into memory */
ret = romfs_devcacheread(rm, sector);
if (ret < 0)
{
return ret;
}
/* Check if this is a hard link */
next = romfs_devread32(rm, ndx + ROMFS_FHDR_NEXT);
if ((next & RFNEXT_MODEMASK) != RFNEXT_HARDLINK)
{
break;
}
/* Follow the hard-link */
offset = romfs_devread32(rm, ndx + ROMFS_FHDR_INFO);
return ret;
}
/* Loop until the header size is obtained. */