void file_buffer_on(FIL *fp)
{
file_buffer_offset = f_tell(fp) % 4;
file_buffer_pointer = fb_alloc_all(&file_buffer_size) + file_buffer_offset;
if (!file_buffer_size) {
nlr_raise(mp_obj_new_exception_msg(&mp_type_MemoryError, "No memory!"));
}
file_buffer_size -= file_buffer_offset;
file_buffer_index = 0;
if (fp->flag & FA_READ) {
uint32_t file_remaining = f_size(fp) - f_tell(fp);
uint32_t can_do = FF_MIN(file_buffer_size, file_remaining);
UINT bytes;
FRESULT res = f_read(fp, file_buffer_pointer, can_do, &bytes);
if (res != FR_OK) ff_fail(fp, res);
if (bytes != can_do) ff_read_fail(fp);
}
}
// returns null pointer without error if returned size==0
void *fb_alloc0_all(uint32_t *size)
{
void *mem = fb_alloc_all(size);
memset(mem, 0, *size); // does nothing if size is zero.
return mem;
}