void BufferedFile::refill_buffer() {
if (at_eof()) {
return;
}
int bytes_to_read = buffer_size();
int max = file_size() - file_pos();
if (bytes_to_read > max) {
bytes_to_read = max;
}
int count_read;
{
// The file_pointer() may be shared with a FileDecoder
// object. This may cause BufferedFile::file_pos() to become out
// of date. A call to OsFile_seek() makes everything consistent again.
AllocationDisabler raw_pointers_used_in_this_block;
Buffer::Raw fb = data_buffer();
OsFile_seek(file_pointer(), file_pos(), SEEK_SET);
count_read = OsFile_read(file_pointer(), fb().base_address(),
1, bytes_to_read);
}
set_count(count_read);
set_file_pos(long(file_pos() + count_read));
set_index(0);
if (count_read <= 0) {
set_at_eof(true);
}
return;
}
int BufferedFile::seek(jint offset, int origin) {
int ndx = index();
int cnt = count();
switch (origin) {
case SEEK_CUR:
// we may have data in the buffer so seek relative to current index into
// buffer
if (cnt > 0) {
// we have some data, so seek from current index
if (offset + ndx >= 0 && offset + ndx < cnt) {
// we are seeking somewhere in the buffer, just set the ndx and return
set_index((int) (ndx + offset));
return 0;
} else {
// we are seeking out of buffer, do a SEEK_CUR to the right position
offset -= (cnt - ndx);
set_file_pos((long)(file_pos() + offset));
}
}
break;
case SEEK_SET:
if (cnt > 0) {
if (offset >= (file_pos() - cnt) && offset < file_pos()) {
// we're seeking in the buffer so just adjust pointer
set_index((int) (cnt - (file_pos() - offset)));
return 0;
}
}
set_file_pos(offset);
break;
case SEEK_END:
if (cnt > 0) {
if (cnt == file_size()) {
// The whole thing is in the buffer so just adjust the index
if ((cnt + offset ) >= 0) {
set_index((int) (cnt + offset));
return 0;
}
}
// There's more data beyond what we have in the buffer so just seek there
}
set_file_pos(long(file_size() + offset));
break;
}
set_count(0); // flush buffer
set_index(0);
if (file_pos() < file_size()) {
set_at_eof(false);
}
return (int) OsFile_seek(file_pointer(), offset, origin);
}
int FileDecoder::get_bytes_raw(address dest_address, int count) {
OsFile_Handle handle = file_handle();
GUARANTEE(handle != NULL, "What are we reading from?");
int pos = file_pos();
OsFile_seek(handle, pos, SEEK_SET);
int bytes_read = OsFile_read(handle, dest_address, 1, count);
set_file_pos(pos + bytes_read);
return bytes_read;
}
inline jint last_unread_file_pos() {
return file_pos() - (count() - index());
}
static int modfile_ftell( INSTANCE * my, int * params )
{
return file_pos(( file * )params[0] ) ;
}
