int
rtems_rfs_block_map_next_block (rtems_rfs_file_system* fs,
rtems_rfs_block_map* map,
rtems_rfs_block_no* block)
{
rtems_rfs_block_pos bpos;
bpos.bno = map->bpos.bno + 1;
bpos.boff = 0;
bpos.block = 0;
return rtems_rfs_block_map_find (fs, map, &bpos, block);
}
int
rtems_rfs_block_map_seek (rtems_rfs_file_system* fs,
rtems_rfs_block_map* map,
rtems_rfs_pos_rel offset,
rtems_rfs_block_no* block)
{
rtems_rfs_block_pos bpos;
rtems_rfs_block_copy_bpos (&bpos, &map->bpos);
rtems_rfs_block_add_pos (fs, offset, &bpos);
return rtems_rfs_block_map_find (fs, map, &bpos, block);
}
int
rtems_rfs_dir_add_entry (rtems_rfs_file_system* fs,
rtems_rfs_inode_handle* dir,
const char* name,
size_t length,
rtems_rfs_ino ino)
{
rtems_rfs_block_map map;
rtems_rfs_block_pos bpos;
rtems_rfs_buffer_handle buffer;
int rc;
if (rtems_rfs_trace (RTEMS_RFS_TRACE_DIR_ADD_ENTRY))
{
int c;
printf ("rtems-rfs: dir-add-entry: dir=%" PRId32 ", name=",
rtems_rfs_inode_ino (dir));
for (c = 0; c < length; c++)
printf ("%c", name[c]);
printf (", len=%zd\n", length);
}
rc = rtems_rfs_block_map_open (fs, dir, &map);
if (rc > 0)
return rc;
rc = rtems_rfs_buffer_handle_open (fs, &buffer);
if (rc > 0)
{
rtems_rfs_block_map_close (fs, &map);
return rc;
}
/*
* Search the map from the beginning to find any empty space.
*/
rtems_rfs_block_set_bpos_zero (&bpos);
while (true)
{
rtems_rfs_block_no block;
uint8_t* entry;
int offset;
bool read = true;
/*
* Locate the first block. If an error the block will be 0. If the map is
* empty which happens when creating a directory and adding the first entry
* the seek will return ENXIO. In this case we need to grow the directory.
*/
rc = rtems_rfs_block_map_find (fs, &map, &bpos, &block);
if (rc > 0)
{
if (rc != ENXIO)
{
if (rtems_rfs_trace (RTEMS_RFS_TRACE_DIR_ADD_ENTRY))
printf ("rtems-rfs: dir-add-entry: "
"block map find failed for ino %" PRIu32 ": %d: %s\n",
rtems_rfs_inode_ino (dir), rc, strerror (rc));
break;
}
/*
* We have reached the end of the directory so add a block.
*/
rc = rtems_rfs_block_map_grow (fs, &map, 1, &block);
if (rc > 0)
{
if (rtems_rfs_trace (RTEMS_RFS_TRACE_DIR_ADD_ENTRY))
printf ("rtems-rfs: dir-add-entry: "
"block map grow failed for ino %" PRIu32 ": %d: %s\n",
rtems_rfs_inode_ino (dir), rc, strerror (rc));
break;
}
read = false;
}
bpos.bno++;
rc = rtems_rfs_buffer_handle_request (fs, &buffer, block, read);
if (rc > 0)
{
if (rtems_rfs_trace (RTEMS_RFS_TRACE_DIR_ADD_ENTRY))
printf ("rtems-rfs: dir-add-entry: "
"block buffer req failed for ino %" PRIu32 ": %d: %s\n",
rtems_rfs_inode_ino (dir), rc, strerror (rc));
break;
}
entry = rtems_rfs_buffer_data (&buffer);
if (!read)
memset (entry, 0xff, rtems_rfs_fs_block_size (fs));
offset = 0;
while (offset < (rtems_rfs_fs_block_size (fs) - RTEMS_RFS_DIR_ENTRY_SIZE))
{
rtems_rfs_ino eino;
int elength;
elength = rtems_rfs_dir_entry_length (entry);
eino = rtems_rfs_dir_entry_ino (entry);
if (elength == RTEMS_RFS_DIR_ENTRY_EMPTY)
{
if ((length + RTEMS_RFS_DIR_ENTRY_SIZE) <
(rtems_rfs_fs_block_size (fs) - offset))
{
uint32_t hash;
hash = rtems_rfs_dir_hash (name, length);
rtems_rfs_dir_set_entry_hash (entry, hash);
rtems_rfs_dir_set_entry_ino (entry, ino);
rtems_rfs_dir_set_entry_length (entry,
RTEMS_RFS_DIR_ENTRY_SIZE + length);
memcpy (entry + RTEMS_RFS_DIR_ENTRY_SIZE, name, length);
rtems_rfs_buffer_mark_dirty (&buffer);
rtems_rfs_buffer_handle_close (fs, &buffer);
rtems_rfs_block_map_close (fs, &map);
return 0;
}
break;
}
if (rtems_rfs_dir_entry_valid (fs, elength, eino))
{
if (rtems_rfs_trace (RTEMS_RFS_TRACE_DIR_ADD_ENTRY))
printf ("rtems-rfs: dir-add-entry: "
"bad length or ino for ino %" PRIu32 ": %u/%" PRId32 " @ %04x\n",
rtems_rfs_inode_ino (dir), elength, eino, offset);
rtems_rfs_buffer_handle_close (fs, &buffer);
rtems_rfs_block_map_close (fs, &map);
return EIO;
}
entry += elength;
offset += elength;
}
}
rtems_rfs_buffer_handle_close (fs, &buffer);
rtems_rfs_block_map_close (fs, &map);
return rc;
}
int
rtems_rfs_file_set_size (rtems_rfs_file_handle* handle,
rtems_rfs_pos new_size)
{
rtems_rfs_block_map* map = rtems_rfs_file_map (handle);
rtems_rfs_pos size;
int rc;
if (rtems_rfs_trace (RTEMS_RFS_TRACE_FILE_IO))
printf ("rtems-rfs: file-set-size: size=%" PRIu64 "\n", new_size);
size = rtems_rfs_file_size (handle);
/*
* If the file is same size do nothing else grow or shrink it ?
*
* If the file does not change size do not update the times.
*/
if (size != new_size)
{
/*
* Short cut for the common truncate on open call.
*/
if (new_size == 0)
{
rc = rtems_rfs_block_map_free_all (rtems_rfs_file_fs (handle), map);
if (rc > 0)
return rc;
}
else
{
if (size < new_size)
{
/*
* Grow. Fill with 0's.
*/
rtems_rfs_pos count;
uint32_t length;
bool read_block;
count = new_size - size;
length = rtems_rfs_fs_block_size (rtems_rfs_file_fs (handle));
read_block = false;
while (count)
{
rtems_rfs_buffer_block block;
rtems_rfs_block_pos bpos;
uint8_t* dst;
/*
* Get the block position for the current end of the file as seen by
* the map. If not found and the EOF grow the map then fill the block
* with 0.
*/
rtems_rfs_block_size_get_bpos (rtems_rfs_block_map_size (map), &bpos);
rc = rtems_rfs_block_map_find (rtems_rfs_file_fs (handle),
map, &bpos, &block);
if (rc > 0)
{
/*
* Have we reached the EOF ?
*/
if (rc != ENXIO)
return rc;
rc = rtems_rfs_block_map_grow (rtems_rfs_file_fs (handle),
map, 1, &block);
if (rc > 0)
return rc;
}
if (count < (length - bpos.boff))
{
length = count + bpos.boff;
read_block = true;
rtems_rfs_block_map_set_size_offset (map, length);
}
else
{
rtems_rfs_block_map_set_size_offset (map, 0);
}
/*
* Only read the block if the length is not the block size.
*/
rc = rtems_rfs_buffer_handle_request (rtems_rfs_file_fs (handle),
rtems_rfs_file_buffer (handle),
block, read_block);
if (rc > 0)
return rc;
dst = rtems_rfs_buffer_data (&handle->buffer);
memset (dst + bpos.boff, 0, length - bpos.boff);
rtems_rfs_buffer_mark_dirty (rtems_rfs_file_buffer (handle));
rc = rtems_rfs_buffer_handle_release (rtems_rfs_file_fs (handle),
rtems_rfs_file_buffer (handle));
if (rc > 0)
return rc;
count -= length - bpos.boff;
}
}
else
{
/*
* Shrink
*/
rtems_rfs_block_no blocks;
uint32_t offset;
blocks =
rtems_rfs_block_map_count (map) -
(((new_size - 1) /
rtems_rfs_fs_block_size (rtems_rfs_file_fs (handle))) + 1);
offset =
new_size % rtems_rfs_fs_block_size (rtems_rfs_file_fs (handle));
if (blocks)
{
int rc;
rc = rtems_rfs_block_map_shrink (rtems_rfs_file_fs (handle),
rtems_rfs_file_map (handle),
blocks);
if (rc > 0)
return rc;
}
rtems_rfs_block_map_set_size_offset (map, offset);
if (rtems_rfs_block_pos_past_end (rtems_rfs_file_bpos (handle),
rtems_rfs_block_map_size (map)))
rtems_rfs_block_size_get_bpos (rtems_rfs_block_map_size (map),
rtems_rfs_file_bpos (handle));
}
}
handle->shared->size.count = rtems_rfs_block_map_count (map);
handle->shared->size.offset = rtems_rfs_block_map_size_offset (map);
if (rtems_rfs_file_update_mtime (handle))
handle->shared->mtime = time (NULL);
}
return 0;
}
int
rtems_rfs_file_seek (rtems_rfs_file_handle* handle,
rtems_rfs_pos pos,
rtems_rfs_pos* new_pos)
{
if (rtems_rfs_trace (RTEMS_RFS_TRACE_FILE_IO))
printf ("rtems-rfs: file-seek: new=%" PRIu64 "\n", pos);
/*
* This call only sets the position if it is in a valid part of the file. The
* user can request past the end of the file then write to extend the
* file. The lseek entry states:
*
* "Although lseek() may position the file offset beyond the end of the
* file, this function does not itself extend the size of the file."
*
* This means the file needs to set the file size to the pos only when a
* write occurs.
*/
if (pos < rtems_rfs_file_shared_get_size (rtems_rfs_file_fs (handle),
handle->shared))
{
rtems_rfs_file_set_bpos (handle, pos);
/*
* If the file has a block check if it maps to the current position and it
* does not release it. That will force us to get the block at the new
* position when the I/O starts.
*/
if (rtems_rfs_buffer_handle_has_block (&handle->buffer))
{
rtems_rfs_buffer_block block;
int rc;
rc = rtems_rfs_block_map_find (rtems_rfs_file_fs (handle),
rtems_rfs_file_map (handle),
rtems_rfs_file_bpos (handle),
&block);
if (rc > 0)
return rc;
if (rtems_rfs_buffer_bnum (&handle->buffer) != block)
{
rc = rtems_rfs_buffer_handle_release (rtems_rfs_file_fs (handle),
rtems_rfs_file_buffer (handle));
if (rc > 0)
return rc;
}
}
}
else
{
/*
* The seek is outside the current file so release any buffer. A write will
* extend the file.
*/
int rc = rtems_rfs_file_io_release (handle);
if (rc > 0)
return rc;
}
*new_pos = pos;
return 0;
}
int
rtems_rfs_file_io_start (rtems_rfs_file_handle* handle,
size_t* available,
bool read)
{
size_t size;
if (rtems_rfs_trace (RTEMS_RFS_TRACE_FILE_IO))
printf ("rtems-rfs: file-io: start: %s pos=%" PRIu32 ":%" PRIu32 "\n",
read ? "read" : "write", handle->bpos.bno, handle->bpos.boff);
if (!rtems_rfs_buffer_handle_has_block (&handle->buffer))
{
rtems_rfs_buffer_block block;
bool request_read;
int rc;
request_read = read;
rc = rtems_rfs_block_map_find (rtems_rfs_file_fs (handle),
rtems_rfs_file_map (handle),
rtems_rfs_file_bpos (handle),
&block);
if (rc > 0)
{
/*
* Has the read reached the EOF ?
*/
if (read && (rc == ENXIO))
{
*available = 0;
return 0;
}
if (rc != ENXIO)
return rc;
if (rtems_rfs_trace (RTEMS_RFS_TRACE_FILE_IO))
printf ("rtems-rfs: file-io: start: grow\n");
rc = rtems_rfs_block_map_grow (rtems_rfs_file_fs (handle),
rtems_rfs_file_map (handle),
1, &block);
if (rc > 0)
return rc;
request_read = false;
}
else
{
/*
* If this is a write check if the write starts within a block or the
* amount of data is less than a block size. If it is read the block
* rather than getting a block to fill.
*/
if (!read &&
(rtems_rfs_file_block_offset (handle) ||
(*available < rtems_rfs_fs_block_size (rtems_rfs_file_fs (handle)))))
request_read = true;
}
if (rtems_rfs_trace (RTEMS_RFS_TRACE_FILE_IO))
printf ("rtems-rfs: file-io: start: block=%" PRIu32 " request-read=%s\n",
block, request_read ? "yes" : "no");
rc = rtems_rfs_buffer_handle_request (rtems_rfs_file_fs (handle),
rtems_rfs_file_buffer (handle),
block, request_read);
if (rc > 0)
return rc;
}
if (read
&& rtems_rfs_block_map_last (rtems_rfs_file_map (handle))
&& rtems_rfs_block_map_size_offset (rtems_rfs_file_map (handle)))
size = rtems_rfs_block_map_size_offset (rtems_rfs_file_map (handle));
else
size = rtems_rfs_fs_block_size (rtems_rfs_file_fs (handle));
*available = size - rtems_rfs_file_block_offset (handle);
if (rtems_rfs_trace (RTEMS_RFS_TRACE_FILE_IO))
printf ("rtems-rfs: file-io: start: available=%zu (%zu)\n",
*available, size);
return 0;
}
