char *
mcview_get_ptr_file (mcview_t * view, off_t byte_index)
{
assert (view->datasource == DS_FILE);
mcview_file_load_data (view, byte_index);
if (mcview_already_loaded (view->ds_file_offset, byte_index, view->ds_file_datalen))
return (char *) (view->ds_file_data + (byte_index - view->ds_file_offset));
return NULL;
}
char *
mcview_get_ptr_file (WView * view, off_t byte_index)
{
#ifdef HAVE_ASSERT_H
assert (view->datasource == DS_FILE);
#endif
mcview_file_load_data (view, byte_index);
if (mcview_already_loaded (view->ds_file_offset, byte_index, view->ds_file_datalen))
return (char *) (view->ds_file_data + (byte_index - view->ds_file_offset));
return NULL;
}
/*static */
void
mcview_file_load_data (mcview_t * view, off_t byte_index)
{
off_t blockoffset;
ssize_t res;
size_t bytes_read;
#ifdef HAVE_ASSERT_H
assert (view->datasource == DS_FILE);
#endif
if (mcview_already_loaded (view->ds_file_offset, byte_index, view->ds_file_datalen))
return;
if (byte_index >= view->ds_file_filesize)
return;
blockoffset = mcview_offset_rounddown (byte_index, view->ds_file_datasize);
if (mc_lseek (view->ds_file_fd, blockoffset, SEEK_SET) == -1)
goto error;
bytes_read = 0;
while (bytes_read < view->ds_file_datasize)
{
res =
mc_read (view->ds_file_fd, view->ds_file_data + bytes_read,
view->ds_file_datasize - bytes_read);
if (res == -1)
goto error;
if (res == 0)
break;
bytes_read += (size_t) res;
}
view->ds_file_offset = blockoffset;
if ((off_t) bytes_read > view->ds_file_filesize - view->ds_file_offset)
{
/* the file has grown in the meantime -- stick to the old size */
view->ds_file_datalen = view->ds_file_filesize - view->ds_file_offset;
}
else
{
view->ds_file_datalen = bytes_read;
}
return;
error:
view->ds_file_datalen = 0;
}