size_t block_store_write(block_store_t *const bs, const size_t block_id, const void *buffer, const size_t nbytes, const size_t offset) {
if (bs && bs->fbm && bs->data_blocks && BLOCKID_VALID(block_id)
&& buffer && nbytes && (nbytes + offset <= BLOCK_SIZE)) {
size_t total_offset = offset + (BLOCK_SIZE * (block_id - FBM_SIZE));
memcpy((void *)(bs->data_blocks + total_offset), buffer, nbytes);
block_store_errno = bitmap_test(bs->fbm, block_id) ? BS_OK : BS_FBM_REQUEST_MISMATCH;
return nbytes;
}
block_store_errno = BS_FATAL;
return 0;
}
// Need to refactor this for V3. Have this switch on FILE_BASED and have it either do
// block_mem_write or block_file_write (both with same params) which then handles everything
// (same for read)
size_t block_store_write(block_store_t *const bs, const size_t block_id, const void *buffer, const size_t nbytes, const size_t offset) {
if (bs && BLOCKID_VALID(block_id) && buffer && nbytes && (nbytes + offset <= BLOCK_SIZE)) {
// Not going to forbid writing of not-in-use blocks (but we'll log it via errno)
bitmap_set(bs->dbm, block_id);
FLAG_SET(bs, DIRTY);
memcpy((void *)(bs->data_blocks + BLOCK_OFFSET_POSITION(block_id, offset)), buffer, nbytes);
bs_errno = bitmap_test(bs->fbm, block_id) ? BS_OK : BS_REQUEST_MISMATCH;
return nbytes;
}
bs_errno = BS_PARAM;
return 0;
}
size_t block_store_release(block_store_t *const bs, const size_t block_id) {
if (bs && bs->fbm && BLOCKID_VALID(block_id)) {
// we could clear the dirty bit, since the info is no longer in use but...
// We'll keep it. Could be useful. Doesn't really hurt anything.
// Keeps it more true to a standard block device.
// You could also use this function to format the specified block for security reasons
bitmap_reset(bs->fbm, block_id);
block_store_errno = BS_OK;
return block_id;
}
block_store_errno = BS_PARAM;
return 0;
}
size_t block_store_read(const block_store_t *const bs, const size_t block_id, void *buffer, const size_t nbytes, const size_t offset) {
if (bs && BLOCKID_VALID(block_id) && buffer && nbytes && (nbytes + offset <= BLOCK_SIZE)) {
// Not going to forbid reading of not-in-use blocks (but we'll log it via the errno)
memcpy(buffer, bs->data_blocks + BLOCK_OFFSET_POSITION(block_id, offset), nbytes);
bs_errno = bitmap_test(bs->fbm, block_id) ? BS_OK : BS_REQUEST_MISMATCH;
return nbytes;
}
// technically we return BS_PARAM even if the internal structure of the BS object is busted
// Which, in reality, would be more of a BS_INTERNAL or a BS_FATAL... but it'll add another branch to everything
// And technically the bs is a parameter...
bs_errno = BS_PARAM;
return 0;
}
bool block_store_request(block_store_t *const bs, const size_t block_id) {
if (bs && BLOCKID_VALID(block_id)) {
if (!bitmap_test(bs->fbm, block_id)) {
bitmap_set(bs->fbm, block_id);
bitmap_set(bs->dbm, FBM_BLOCK_CHANGE_LOCATION(block_id));
// Set that FBM block as changed
FLAG_SET(bs, DIRTY);
bs_errno = BS_OK;
return true;
} else {
bs_errno = BS_IN_USE;
return false;
}
}
bs_errno = BS_PARAM;
return false;
}