/**
* This routine processes the lseek() system call.
*
* @param iop
* @param offset
* @param whence
* @return off_t
*/
static off_t
rtems_rfs_rtems_file_lseek (rtems_libio_t* iop,
off_t offset,
int whence)
{
rtems_rfs_file_handle* file = rtems_rfs_rtems_get_iop_file_handle (iop);
off_t old_offset;
off_t new_offset;
if (rtems_rfs_rtems_trace (RTEMS_RFS_RTEMS_DEBUG_FILE_LSEEK))
printf("rtems-rfs: file-lseek: handle:%p offset:%" PRIdoff_t "\n", file, offset);
rtems_rfs_rtems_lock (rtems_rfs_file_fs (file));
old_offset = iop->offset;
new_offset = rtems_filesystem_default_lseek_file (iop, offset, whence);
if (new_offset != -1)
{
rtems_rfs_pos pos = iop->offset;
int rc = rtems_rfs_file_seek (file, pos, &pos);
if (rc)
{
rtems_rfs_rtems_error ("file_lseek: lseek", rc);
iop->offset = old_offset;
new_offset = -1;
}
}
rtems_rfs_rtems_unlock (rtems_rfs_file_fs (file));
return new_offset;
}
/**
* This routine processes the lseek() system call.
*
* @param iop
* @param offset
* @param whence
* @return off_t
*/
static off_t
rtems_rfs_rtems_file_lseek (rtems_libio_t* iop,
off_t offset,
int whence)
{
rtems_rfs_file_handle* file = rtems_rfs_rtems_get_iop_file_handle (iop);
rtems_rfs_pos pos;
int rc;
if (rtems_rfs_rtems_trace (RTEMS_RFS_RTEMS_DEBUG_FILE_LSEEK))
printf("rtems-rfs: file-lseek: handle:%p offset:%" PRIdoff_t "\n", file, offset);
rtems_rfs_rtems_lock (rtems_rfs_file_fs (file));
pos = iop->offset;
rc = rtems_rfs_file_seek (file, pos, &pos);
if (rc)
{
rtems_rfs_rtems_unlock (rtems_rfs_file_fs (file));
return rtems_rfs_rtems_error ("file_lseek: lseek", rc);
}
rtems_rfs_rtems_unlock (rtems_rfs_file_fs (file));
return iop->offset;
}
/**
* This routine processes the read() system call.
*
* @param iop
* @param buffer
* @param count
* @return int
*/
static ssize_t
rtems_rfs_rtems_file_read (rtems_libio_t* iop,
void* buffer,
size_t count)
{
rtems_rfs_file_handle* file = rtems_rfs_rtems_get_iop_file_handle (iop);
rtems_rfs_pos pos;
uint8_t* data = buffer;
ssize_t read = 0;
int rc;
if (rtems_rfs_rtems_trace (RTEMS_RFS_RTEMS_DEBUG_FILE_READ))
printf("rtems-rfs: file-read: handle:%p count:%zd\n", file, count);
rtems_rfs_rtems_lock (rtems_rfs_file_fs (file));
pos = iop->offset;
if (pos < rtems_rfs_file_size (file))
{
while (count)
{
size_t size;
rc = rtems_rfs_file_io_start (file, &size, true);
if (rc > 0)
{
read = rtems_rfs_rtems_error ("file-read: read: io-start", rc);
break;
}
if (size == 0)
break;
if (size > count)
size = count;
memcpy (data, rtems_rfs_file_data (file), size);
data += size;
count -= size;
read += size;
rc = rtems_rfs_file_io_end (file, size, true);
if (rc > 0)
{
read = rtems_rfs_rtems_error ("file-read: read: io-end", rc);
break;
}
}
}
if (read >= 0)
iop->offset = pos + read;
rtems_rfs_rtems_unlock (rtems_rfs_file_fs (file));
return read;
}
int
rtems_rfs_file_io_release (rtems_rfs_file_handle* handle)
{
int rc = 0;
if (rtems_rfs_buffer_handle_has_block (&handle->buffer))
rc = rtems_rfs_buffer_handle_release (rtems_rfs_file_fs (handle),
rtems_rfs_file_buffer (handle));
return rc;
}
/**
* This routine processes the ftruncate() system call.
*
* @param iop
* @param length
* @return int
*/
static int
rtems_rfs_rtems_file_ftruncate (rtems_libio_t* iop,
off_t length)
{
rtems_rfs_file_handle* file = rtems_rfs_rtems_get_iop_file_handle (iop);
int rc;
if (rtems_rfs_rtems_trace (RTEMS_RFS_RTEMS_DEBUG_FILE_FTRUNC))
printf("rtems-rfs: file-ftrunc: handle:%p length:%" PRIdoff_t "\n", file, length);
rtems_rfs_rtems_lock (rtems_rfs_file_fs (file));
rc = rtems_rfs_file_set_size (file, length);
if (rc)
rc = rtems_rfs_rtems_error ("file_ftruncate: set size", rc);
rtems_rfs_rtems_unlock (rtems_rfs_file_fs (file));
return rc;
}
/**
* This routine processes the close() system call. Note that there is nothing
* to flush at this point.
*
* @param iop
* @return int
*/
static int
rtems_rfs_rtems_file_close (rtems_libio_t* iop)
{
rtems_rfs_file_handle* file = rtems_rfs_rtems_get_iop_file_handle (iop);
rtems_rfs_file_system* fs = rtems_rfs_file_fs (file);
int rc;
if (rtems_rfs_rtems_trace (RTEMS_RFS_RTEMS_DEBUG_FILE_CLOSE))
printf("rtems-rfs: file-close: handle:%p\n", file);
rtems_rfs_rtems_lock (fs);
rc = rtems_rfs_file_close (fs, file);
if (rc > 0)
rc = rtems_rfs_rtems_error ("file-close: file close", rc);
rtems_rfs_rtems_unlock (fs);
return rc;
}
/**
* This routine processes the write() system call.
*
* @param iop
* @param buffer
* @param count
* @return ssize_t
*/
static ssize_t
rtems_rfs_rtems_file_write (rtems_libio_t* iop,
const void* buffer,
size_t count)
{
rtems_rfs_file_handle* file = rtems_rfs_rtems_get_iop_file_handle (iop);
rtems_rfs_pos pos;
rtems_rfs_pos file_size;
const uint8_t* data = buffer;
ssize_t write = 0;
int rc;
if (rtems_rfs_rtems_trace (RTEMS_RFS_RTEMS_DEBUG_FILE_WRITE))
printf("rtems-rfs: file-write: handle:%p count:%zd\n", file, count);
rtems_rfs_rtems_lock (rtems_rfs_file_fs (file));
pos = iop->offset;
file_size = rtems_rfs_file_size (file);
if (pos > file_size)
{
/*
* If the iop position is past the physical end of the file we need to set
* the file size to the new length before writing. The
* rtems_rfs_file_io_end() will grow the file subsequently.
*/
rc = rtems_rfs_file_set_size (file, pos);
if (rc)
{
rtems_rfs_rtems_unlock (rtems_rfs_file_fs (file));
return rtems_rfs_rtems_error ("file-write: write extend", rc);
}
rtems_rfs_file_set_bpos (file, pos);
}
else if (pos < file_size && rtems_libio_iop_is_append(iop))
{
pos = file_size;
rc = rtems_rfs_file_seek (file, pos, &pos);
if (rc)
{
rtems_rfs_rtems_unlock (rtems_rfs_file_fs (file));
return rtems_rfs_rtems_error ("file-write: write append seek", rc);
}
}
while (count)
{
size_t size = count;
rc = rtems_rfs_file_io_start (file, &size, false);
if (rc)
{
/*
* If we have run out of space and have written some data return that
* amount first as the inode will have accounted for it. This means
* there was no error and the return code from can be ignored.
*/
if (!write)
write = rtems_rfs_rtems_error ("file-write: write open", rc);
break;
}
if (size > count)
size = count;
memcpy (rtems_rfs_file_data (file), data, size);
data += size;
count -= size;
write += size;
rc = rtems_rfs_file_io_end (file, size, false);
if (rc)
{
write = rtems_rfs_rtems_error ("file-write: write close", rc);
break;
}
}
if (write >= 0)
iop->offset = pos + write;
rtems_rfs_rtems_unlock (rtems_rfs_file_fs (file));
return write;
}
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_end (rtems_rfs_file_handle* handle,
size_t size,
bool read)
{
bool atime;
bool mtime;
bool length;
int rc = 0;
if (rtems_rfs_trace (RTEMS_RFS_TRACE_FILE_IO))
printf ("rtems-rfs: file-io: end: %s size=%zu\n",
read ? "read" : "write", size);
if (rtems_rfs_buffer_handle_has_block (&handle->buffer))
{
if (!read)
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)
{
printf (
"rtems-rfs: file-io: end: error on release: %s size=%zu: %d: %s\n",
read ? "read" : "write", size, rc, strerror (rc));
return rc;
}
}
/*
* Update the handle's position. Only a block size can be handled at a time
* so no special maths is needed. If the offset is bigger than the block size
* increase the block number and adjust the offset.
*
* If we are the last block and the position is past the current size update
* the size with the new length. The map holds the block count.
*/
handle->bpos.boff += size;
if (handle->bpos.boff >=
rtems_rfs_fs_block_size (rtems_rfs_file_fs (handle)))
{
handle->bpos.bno++;
handle->bpos.boff -= rtems_rfs_fs_block_size (rtems_rfs_file_fs (handle));
}
length = false;
mtime = false;
if (!read &&
rtems_rfs_block_map_past_end (rtems_rfs_file_map (handle),
rtems_rfs_file_bpos (handle)))
{
rtems_rfs_block_map_set_size_offset (rtems_rfs_file_map (handle),
handle->bpos.boff);
length = true;
mtime = true;
}
atime = rtems_rfs_file_update_atime (handle);
mtime = rtems_rfs_file_update_mtime (handle) && mtime;
length = rtems_rfs_file_update_length (handle) && length;
if (rtems_rfs_trace (RTEMS_RFS_TRACE_FILE_IO))
printf ("rtems-rfs: file-io: end: pos=%" PRIu32 ":%" PRIu32 " %c %c %c\n",
handle->bpos.bno, handle->bpos.boff,
atime ? 'A' : '-', mtime ? 'M' : '-', length ? 'L' : '-');
if (atime || mtime)
{
time_t now = time (NULL);
if (read && atime)
handle->shared->atime = now;
if (!read && mtime)
handle->shared->mtime = now;
}
if (length)
{
handle->shared->size.count =
rtems_rfs_block_map_count (rtems_rfs_file_map (handle));
handle->shared->size.offset =
rtems_rfs_block_map_size_offset (rtems_rfs_file_map (handle));
}
return rc;
}
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;
}
/**
* This routine processes the write() system call.
*
* @param iop
* @param buffer
* @param count
* @return ssize_t
*/
static ssize_t
rtems_rfs_rtems_file_write (rtems_libio_t* iop,
const void* buffer,
size_t count)
{
rtems_rfs_file_handle* file = rtems_rfs_rtems_get_iop_file_handle (iop);
rtems_rfs_pos pos;
const uint8_t* data = buffer;
ssize_t write = 0;
int rc;
if (rtems_rfs_rtems_trace (RTEMS_RFS_RTEMS_DEBUG_FILE_WRITE))
printf("rtems-rfs: file-write: handle:%p count:%zd\n", file, count);
rtems_rfs_rtems_lock (rtems_rfs_file_fs (file));
pos = iop->offset;
/*
* If the iop position is past the physical end of the file we need to set
* the file size to the new length before writing. If the position equals the
* size of file we are still past the end of the file as positions number
* from 0. For a specific position we need a file that has a length of one
* more.
*/
if (pos >= rtems_rfs_file_size (file))
{
rc = rtems_rfs_file_set_size (file, pos + 1);
if (rc)
{
rtems_rfs_rtems_unlock (rtems_rfs_file_fs (file));
return rtems_rfs_rtems_error ("file-write: write extend", rc);
}
}
rtems_rfs_file_set_bpos (file, pos);
while (count)
{
size_t size = count;
rc = rtems_rfs_file_io_start (file, &size, false);
if (rc)
{
write = rtems_rfs_rtems_error ("file-write: write open", rc);
break;
}
if (size > count)
size = count;
memcpy (rtems_rfs_file_data (file), data, size);
data += size;
count -= size;
write += size;
rc = rtems_rfs_file_io_end (file, size, false);
if (rc)
{
write = rtems_rfs_rtems_error ("file-write: write close", rc);
break;
}
}
iop->size = rtems_rfs_file_size (file);
rtems_rfs_rtems_unlock (rtems_rfs_file_fs (file));
return write;
}
