int nxffs_stat(FAR struct inode *mountpt, FAR const char *relpath,
FAR struct stat *buf)
{
FAR struct nxffs_volume_s *volume;
struct nxffs_entry_s entry;
int ret;
fvdbg("Entry\n");
/* Sanity checks */
DEBUGASSERT(mountpt && mountpt->i_private && buf);
/* Get the mountpoint private data from the NuttX inode structure */
volume = mountpt->i_private;
ret = sem_wait(&volume->exclsem);
if (ret != OK)
{
goto errout;
}
/* Initialize the return stat instance */
memset(buf, 0, sizeof(struct stat));
buf->st_blksize = volume->geo.blocksize;
buf->st_blocks = entry.datlen / (volume->geo.blocksize - SIZEOF_NXFFS_BLOCK_HDR);
/* The requested directory must be the volume-relative "root" directory */
if (relpath && relpath[0] != '\0')
{
/* Not the top directory.. find the NXFFS inode with this name */
ret = nxffs_findinode(volume, relpath, &entry);
if (ret < 0)
{
fdbg("ERROR: Inode '%s' not found: %d\n", -ret);
goto errout_with_semaphore;
}
buf->st_mode = S_IFREG|S_IXOTH|S_IXGRP|S_IXUSR;
buf->st_size = entry.datlen;
buf->st_atime = entry.utc;
buf->st_mtime = entry.utc;
buf->st_ctime = entry.utc;
/* Free inode resources */
nxffs_freeentry(&entry);
}
else
{
/* It's a read/execute-only directory name */
buf->st_mode = S_IFDIR|S_IROTH|S_IRGRP|S_IRUSR|S_IXOTH|S_IXGRP|S_IXUSR;
}
ret = OK;
errout_with_semaphore:
sem_post(&volume->exclsem);
errout:
return ret;
}
static inline int nxffs_wropen(FAR struct nxffs_volume_s *volume,
FAR const char *name, mode_t oflags,
FAR struct nxffs_ofile_s **ppofile)
{
FAR struct nxffs_wrfile_s *wrfile;
FAR struct nxffs_entry_s entry;
bool packed;
bool truncate = false;
int namlen;
int ret;
/* Limitation: Only a single writer is permitted. Writing may involve
* extension of the file system in FLASH. Since files are contiguous
* in FLASH, only a single file may be extending the FLASH region.
*/
ret = sem_wait(&volume->wrsem);
if (ret != OK)
{
fdbg("ERROR: sem_wait failed: %d\n", ret);
ret = -get_errno();
goto errout;
}
/* Get exclusive access to the volume. Note that the volume exclsem
* protects the open file list. Note that exclsem is ALWAYS taken
* after wrsem to avoid deadlocks.
*/
ret = sem_wait(&volume->exclsem);
if (ret != OK)
{
fdbg("ERROR: sem_wait failed: %d\n", ret);
ret = -get_errno();
goto errout_with_wrsem;
}
/* Check if the file exists */
ret = nxffs_findinode(volume, name, &entry);
if (ret == OK)
{
FAR struct nxffs_ofile_s *ofile;
/* It exists. Release the entry. */
nxffs_freeentry(&entry);
/* Is the file already open for reading? */
ofile = nxffs_findofile(volume, name);
if (ofile)
{
/* The file is already open.
* Limitation: Files cannot be open both for reading and writing.
*/
fdbg("ERROR: File is open for reading\n");
ret = -ENOSYS;
goto errout_with_exclsem;
}
/* It would be an error if we are asked to create the file
* exclusively.
*/
else if ((oflags & (O_CREAT|O_EXCL)) == (O_CREAT|O_EXCL))
{
fdbg("ERROR: File exists, can't create O_EXCL\n");
ret = -EEXIST;
goto errout_with_exclsem;
}
/* Were we asked to truncate the file? NOTE: Don't truncate the
* file if we were not also asked to created it. See below...
* we will not re-create the file unless O_CREAT is also specified.
*/
else if ((oflags & (O_CREAT|O_TRUNC)) == (O_CREAT|O_TRUNC))
{
/* Just schedule the removal the file and fall through to re-create it.
* Note that the old file of the same name will not actually be removed
* until the new file is successfully written.
*/
truncate = true;
}
/* The file exists and we were not asked to truncate (and recreate) it.
* Limitation: Cannot write to existing files.
*/
else
{
fdbg("ERROR: File %s exists and we were not asked to truncate it\n");
ret = -ENOSYS;
goto errout_with_exclsem;
}
}
/* Okay, the file is not open and does not exists (maybe because we deleted
* it). Now, make sure that we were asked to created it.
*/
if ((oflags & O_CREAT) == 0)
{
fdbg("ERROR: Not asked to create the file\n");
ret = -ENOENT;
goto errout_with_exclsem;
}
/* Make sure that the length of the file name will fit in a uint8_t */
namlen = strlen(name);
if (namlen > CONFIG_NXFFS_MAXNAMLEN)
{
fdbg("ERROR: Name is too long: %d\n", namlen);
ret = -EINVAL;
goto errout_with_exclsem;
}
/* Yes.. Create a new structure that will describe the state of this open
* file. NOTE that a special variant of the open file structure is used
* that includes additional information to support the write operation.
*/
#ifdef CONFIG_NXFFS_PREALLOCATED
wrfile = &g_wrfile;
memset(wrfile, 0, sizeof(struct nxffs_wrfile_s));
#else
wrfile = (FAR struct nxffs_wrfile_s *)kmm_zalloc(sizeof(struct nxffs_wrfile_s));
if (!wrfile)
{
ret = -ENOMEM;
goto errout_with_exclsem;
}
#endif
/* Initialize the open file state structure */
wrfile->ofile.crefs = 1;
wrfile->ofile.oflags = oflags;
wrfile->ofile.entry.utc = time(NULL);
wrfile->truncate = truncate;
/* Save a copy of the inode name. */
wrfile->ofile.entry.name = strdup(name);
if (!wrfile->ofile.entry.name)
{
ret = -ENOMEM;
goto errout_with_ofile;
}
/* Allocate FLASH memory for the file and set up for the write.
*
* Loop until the inode header is configured or until a failure occurs.
* Note that nothing is written to FLASH. The inode header is not
* written until the file is closed.
*/
packed = false;
for (;;)
{
/* File a valid location to position the inode header. Start with the
* first byte in the free FLASH region.
*/
ret = nxffs_hdrpos(volume, wrfile);
if (ret == OK)
{
/* Find a region of memory in the block that is fully erased */
ret = nxffs_hdrerased(volume, wrfile);
if (ret == OK)
{
/* Valid memory for the inode header was found. Break out of
* the loop.
*/
break;
}
}
/* If no valid memory is found searching to the end of the volume,
* then -ENOSPC will be returned. Other errors are not handled.
*/
if (ret != -ENOSPC || packed)
{
fdbg("ERROR: Failed to find inode header memory: %d\n", -ret);
goto errout_with_name;
}
/* -ENOSPC is a special case.. It means that the volume is full.
* Try to pack the volume in order to free up some space.
*/
ret = nxffs_pack(volume);
if (ret < 0)
{
fdbg("ERROR: Failed to pack the volume: %d\n", -ret);
goto errout_with_name;
}
/* After packing the volume, froffset will be updated to point to the
* new free flash region. Try again.
*/
packed = true;
}
/* Loop until the inode name is configured or until a failure occurs.
* Note that nothing is written to FLASH.
*/
for (;;)
{
/* File a valid location to position the inode name. Start with the
* first byte in the free FLASH region.
*/
ret = nxffs_nampos(volume, wrfile, namlen);
if (ret == OK)
{
/* Find a region of memory in the block that is fully erased */
ret = nxffs_namerased(volume, wrfile, namlen);
if (ret == OK)
{
/* Valid memory for the inode header was found. Write the
* inode name to this location.
*/
ret = nxffs_wrname(volume, &wrfile->ofile.entry, namlen);
if (ret < 0)
{
fdbg("ERROR: Failed to write the inode name: %d\n", -ret);
goto errout_with_name;
}
/* Then just break out of the loop reporting success. Note
* that the alllocated inode name string is retained; it
* will be needed later to calculate the inode CRC.
*/
break;
}
}
/* If no valid memory is found searching to the end of the volume,
* then -ENOSPC will be returned. Other errors are not handled.
*/
if (ret != -ENOSPC || packed)
{
fdbg("ERROR: Failed to find inode name memory: %d\n", -ret);
goto errout_with_name;
}
/* -ENOSPC is a special case.. It means that the volume is full.
* Try to pack the volume in order to free up some space.
*/
ret = nxffs_pack(volume);
if (ret < 0)
{
fdbg("ERROR: Failed to pack the volume: %d\n", -ret);
goto errout_with_name;
}
/* After packing the volume, froffset will be updated to point to the
* new free flash region. Try again.
*/
packed = true;
}
/* Add the open file structure to the head of the list of open files */
wrfile->ofile.flink = volume->ofiles;
volume->ofiles = &wrfile->ofile;
/* Indicate that the volume is open for writing and return the open file
* instance. Releasing exclsem allows other readers while the write is
* in progress. But wrsem is still held for this open file, preventing
* any further writers until this inode is closed.s
*/
*ppofile = &wrfile->ofile;
sem_post(&volume->exclsem);
return OK;
errout_with_name:
kmm_free(wrfile->ofile.entry.name);
errout_with_ofile:
#ifndef CONFIG_NXFFS_PREALLOCATED
kmm_free(wrfile);
#endif
errout_with_exclsem:
sem_post(&volume->exclsem);
errout_with_wrsem:
sem_post(&volume->wrsem);
errout:
return ret;
}
static inline int nxffs_rdopen(FAR struct nxffs_volume_s *volume,
FAR const char *name,
FAR struct nxffs_ofile_s **ppofile)
{
FAR struct nxffs_ofile_s *ofile;
int ret;
/* Get exclusive access to the volume. Note that the volume exclsem
* protects the open file list.
*/
ret = sem_wait(&volume->exclsem);
if (ret != OK)
{
fdbg("ERROR: sem_wait failed: %d\n", ret);
ret = -get_errno();
goto errout;
}
/* Check if the file has already been opened (for reading) */
ofile = nxffs_findofile(volume, name);
if (ofile)
{
/* The file is already open.
* Limitation: Files cannot be open both for reading and writing.
*/
if ((ofile->oflags & O_WROK) != 0)
{
fdbg("ERROR: File is open for writing\n");
ret = -ENOSYS;
goto errout_with_exclsem;
}
/* Just increment the reference count on the ofile */
ofile->crefs++;
fvdbg("crefs: %d\n", ofile->crefs);
}
/* The file has not yet been opened.
* Limitation: The file must exist. We do not support creation of files
* read-only.
*/
else
{
/* Not already open.. create a new open structure */
ofile = (FAR struct nxffs_ofile_s *)kmm_zalloc(sizeof(struct nxffs_ofile_s));
if (!ofile)
{
fdbg("ERROR: ofile allocation failed\n");
ret = -ENOMEM;
goto errout_with_exclsem;
}
/* Initialize the open file state structure */
ofile->crefs = 1;
ofile->oflags = O_RDOK;
/* Find the file on this volume associated with this file name */
ret = nxffs_findinode(volume, name, &ofile->entry);
if (ret != OK)
{
fvdbg("Inode '%s' not found: %d\n", name, -ret);
goto errout_with_ofile;
}
/* Add the open file structure to the head of the list of open files */
ofile->flink = volume->ofiles;
volume->ofiles = ofile;
}
/* Return the open file state structure */
*ppofile = ofile;
sem_post(&volume->exclsem);
return OK;
errout_with_ofile:
kmm_free(ofile);
errout_with_exclsem:
sem_post(&volume->exclsem);
errout:
return ret;
}
int nxffs_rminode(FAR struct nxffs_volume_s *volume, FAR const char *name)
{
FAR struct nxffs_ofile_s *ofile;
FAR struct nxffs_inode_s *inode;
struct nxffs_entry_s entry;
int ret;
/* Check if the file is open */
ofile = nxffs_findofile(volume, name);
if (ofile)
{
/* We can't remove the inode if it is open */
fdbg("Inode '%s' is open\n", name);
ret = -EBUSY;
goto errout;
}
/* Find the NXFFS inode */
ret = nxffs_findinode(volume, name, &entry);
if (ret < 0)
{
fdbg("Inode '%s' not found\n", name);
goto errout;
}
/* Set the position to the FLASH offset of the file header (nxffs_findinode
* should have left the block in the cache).
*/
nxffs_ioseek(volume, entry.hoffset);
/* Make sure that the block is in the cache */
ret = nxffs_rdcache(volume, volume->ioblock);
if (ret < 0)
{
fdbg("Failed to read data into cache: %d\n", ret);
goto errout_with_entry;
}
/* Change the file status... it is no longer valid */
inode = (FAR struct nxffs_inode_s *)&volume->cache[volume->iooffset];
inode->state = INODE_STATE_DELETED;
/* Then write the cached block back to FLASH */
ret = nxffs_wrcache(volume);
if (ret < 0)
{
fdbg("Failed to read data into cache: %d\n", ret);
}
errout_with_entry:
nxffs_freeentry(&entry);
errout:
return ret;
}
