/**
* Given the given fragmentation threshold, determine whether the given bundle should be split
* into several smaller bundles. If so, this returns true and generates a bunch of bundle received
* events for the individual fragments.
*
* @param bundle Bundle to split into fragments
* @param link Bundle to send on the given link
* @param max_length Maximum length of the fragment
* @return FragmentState that has the list of created fragments for the given bundle.
*/
public FragmentState proactively_fragment(Bundle bundle, final Link link, int max_length) {
int payload_len = bundle.payload().length();
Bundle fragment;
FragmentState state = new FragmentState(bundle);
int todo = payload_len;
int offset = 0;
int count = 0;
BlockInfoVec first_frag_blocks = new BlockInfoVec();
BlockInfoVec all_frag_blocks = new BlockInfoVec();
BlockInfoVec this_frag_blocks = first_frag_blocks;
ListIterator<BlockInfo> entry = bundle.xmit_link_block_set().find_blocks(link).listIterator();
while (entry.hasNext()) {
BlockInfo block_info = entry.next();
if ((block_info.type() == bundle_block_type_t.PRIMARY_BLOCK)
|| (block_info.type() == bundle_block_type_t.PAYLOAD_BLOCK)) {
all_frag_blocks.add(block_info);
first_frag_blocks.add(block_info);
} else if ((block_info.flags() & block_flag_t.BLOCK_FLAG_REPLICATE.getCode()) > 0) {
all_frag_blocks.add(block_info);
} else {
first_frag_blocks.add(block_info);
}
}
do {
fragment = create_fragment(bundle, link, this_frag_blocks, offset, max_length);
assert (fragment != null) : TAG + ": proactively_fragment() fragment not valid";
state.add_fragment(fragment);
offset += fragment.payload().length();
todo -= fragment.payload().length();
this_frag_blocks = all_frag_blocks;
++count;
} while (todo > 0);
Logger.getInstance()
.debug(
TAG,
String.format(
"proactively fragmenting " + "%s byte payload into %s %s byte fragments",
payload_len, count, max_length));
String[] hash_key = new String[1];
get_hash_key(fragment, hash_key);
fragment_table_.put(hash_key[0], state);
return state;
}
/**
* Prepare function prepare bundle to generate. It adds Primary Block Info at the start of
* xmit_blocks and add endpoint eids at the start of dictionary.
*
* @param bundle Bundle to prepare
* @param xmit_blocks Empty xmit_blocks of the blundle
* @param source Source endpoint id
* @param link Link of the bundle
* @param list Owner type
* @return Return success message on success
*/
public int prepare(
final Bundle bundle,
BlockInfoVec xmit_blocks,
final BlockInfo source,
final Link link,
list_owner_t list) {
// There shouldn't already be anything in the xmit_blocks
assert (xmit_blocks.size() == 0)
: TAG + ": prepare() there shouldn't be anything already in xmit_blocks";
// Add EIDs to start off the dictionary
xmit_blocks.dict().add_eid(bundle.dest());
xmit_blocks.dict().add_eid(bundle.source());
xmit_blocks.dict().add_eid(bundle.replyto());
xmit_blocks.dict().add_eid(bundle.custodian());
// make sure to add the primary to the front
xmit_blocks.add(0, new BlockInfo(this, source));
return BP_SUCCESS;
}
/**
* Create a fragment to be sent out on a particular link.
*
* @param bundle Source Bundle from which we create a fragment.
* @param link Link on which we will send the fragment
* @param blocks_to_copy Blocks to copy on this fragment.
* @param offset The offset relative to this bundle for the for the new fragment
* @param max_length Maximum length of the newly created fragment
* @return Newly created fragment.
*/
public Bundle create_fragment(
Bundle bundle,
final Link link,
final BlockInfoVec blocks_to_copy,
int offset,
int max_length) {
int block_length = 0;
ListIterator<BlockInfo> entry = blocks_to_copy.listIterator();
BlockInfo block_i;
while (entry.hasNext()) {
block_i = entry.next();
if (block_i.type() == bundle_block_type_t.PRIMARY_BLOCK) {
block_length += block_i.data_length();
} else {
block_length += block_i.data_offset(); // data offset is the
// starting point of
}
}
if (block_length > max_length) {
Logger.getInstance()
.error(
TAG,
String.format(
"unable to create a fragment of length %s; minimum length " + "required is %s",
max_length, block_length));
return null;
}
Bundle fragment = new Bundle(location_t.DISK);
// copy the metadata into the new fragment (which can be further
// fragmented)
bundle.copy_metadata(fragment);
fragment.set_is_fragment(true);
fragment.set_do_not_fragment(false);
// initialize the fragment's orig_length and figure out the offset
// into the payload
if (!bundle.is_fragment()) {
fragment.set_orig_length(bundle.payload().length());
fragment.set_frag_offset(offset);
} else {
fragment.set_orig_length(bundle.orig_length());
fragment.set_frag_offset(bundle.frag_offset() + offset);
}
// initialize payload
int to_copy = Math.min(max_length - block_length, bundle.payload().length() - offset);
fragment.payload().set_length(to_copy);
fragment.payload().write_data(bundle.payload(), offset, to_copy, 0);
BlockInfoVec xmit_blocks = fragment.xmit_link_block_set().create_blocks(link);
entry = blocks_to_copy.listIterator(); // reset Iterator
while (entry.hasNext()) {
block_i = entry.next();
xmit_blocks.add(block_i);
}
Logger.getInstance()
.debug(
TAG,
String.format(
"created %s byte fragment bundle with %s bytes of payload",
to_copy + block_length, to_copy));
return fragment;
}
