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use errors::*;
use network_msgs::*;
use protocol::{DatNetMessage, DatConnection};
use integer_encoding::VarInt;
use bit_field::BitArray;
use sleep_register::HyperRegister;
fn decode_bitfiled(raw_bf: &[u8]) -> Result<Vec<u8>> {
let mut offset = 0; // byte offset that we have read up to
if raw_bf.len() < 1 {
bail!("Expected (varint-encoded) bitfield to have len>=1");
}
let mut bit_array: Vec<u8> = vec![];
while offset < raw_bf.len() {
let (header, inc): (u64, usize) = VarInt::decode_var(&raw_bf[offset..]);
offset += inc;
if (header & 0x01) == 0x01 {
// compressed
let bit = (header & 0x02) == 0x02;
let run_len = header >> 2;
if bit {
bit_array.append(&mut vec![0xFF; run_len as usize]);
} else {
bit_array.append(&mut vec![0x00; run_len as usize]);
}
} else {
// uncompressed
let byte_count = header >> 1;
let mut data = raw_bf[offset..(offset + byte_count as usize)].to_vec();
bit_array.append(&mut data);
offset += byte_count as usize;
}
}
// XXX: HACK
bit_array.reverse();
return Ok(bit_array);
}
/// Finds the index of the lowest bit
fn max_high_bit(bf: &[u8]) -> u64 {
// XXX: HACK, going backwards
for i in 0..bf.bit_length() {
if bf.get_bit(i) {
return (bf.bit_length() - i - 1) as u64;
}
}
return 0;
}
fn max_index(have_msg: &Have) -> Result<u64> {
if have_msg.has_length() {
return Ok(have_msg.get_start() + have_msg.get_length());
} else if have_msg.has_bitfield() {
let raw_bf = have_msg.get_bitfield();
let bf = decode_bitfiled(raw_bf)?;
trace!("decoded bitfield: {:?}", bf);
return Ok(max_high_bit(&bf));
} else {
return Ok(have_msg.get_start() + 1);
}
}
#[test]
fn test_max_index() {
let mut hm = Have::new();
hm.set_start(0);
hm.set_bitfield(vec![7,2,128]);
assert_eq!(max_index(&hm).unwrap(), 8);
hm.set_bitfield(vec![2, 207]);
assert_eq!(max_index(&hm).unwrap(), 7);
// Alphabet test dat
hm.set_bitfield(vec![2, 254]);
assert_eq!(max_index(&hm).unwrap(), 6);
hm.set_bitfield(vec![2, 252]);
assert_eq!(max_index(&hm).unwrap(), 5);
}
/// Tries to connect to a single peer, pull register, and close.
pub fn node_simple_clone(host_port: &str, key: &[u8], register: &mut HyperRegister, is_content: bool) -> Result<()> {
if register.len()? > 0 {
bail!("Register already had data in it (expected empty for naive clone)");
}
let mut dc = DatConnection::connect(host_port, key, false)?;
// Info: downloading, not uploading
let mut im = Info::new();
im.set_uploading(false);
im.set_downloading(true);
let im = DatNetMessage::Info(im);
dc.send_msg(&im, is_content)?;
// Have: nothing (so far)
let mut hm = Have::new();
hm.set_start(0);
hm.set_length(0);
let hm = DatNetMessage::Have(hm);
dc.send_msg(&hm, is_content)?;
// UnHave: still nothing
let mut uhm = Unhave::new();
uhm.set_start(0);
let uhm = DatNetMessage::Unhave(uhm);
dc.send_msg(&uhm, is_content)?;
// Want: everything
let mut wm = Want::new();
wm.set_start(0);
let wm = DatNetMessage::Want(wm);
dc.send_msg(&wm, is_content)?;
let last_entry: u64;
// Receive Have messages to determine lengths
loop {
let (was_content, msg) = dc.recv_msg()?;
match msg {
DatNetMessage::Have(dh) => {
info!("is_content={}; {:?}; bitfield={:?}", was_content, dh, dh.get_bitfield());
last_entry = max_index(&dh)?;
break;
},
_ => {
info!("Other message: {:?}", &msg);
}
}
}
info!("last_entry={}", last_entry);
// Request / Data loops
for i in 0..(last_entry+1) {
let mut rm = Request::new();
rm.set_index(i);
info!("Sending request: {:?}", rm);
dc.send_msg(&DatNetMessage::Request(rm), false)?;
let (was_content, msg) = dc.recv_msg()?;
assert!(!was_content);
match msg {
DatNetMessage::Data(dm) => {
info!("Got data: index={}", dm.get_index());
assert!(dm.has_value());
assert!(dm.get_index() == i);
register.append(dm.get_value())?;
},
_ => {
info!("Other message: {:?}", &msg);
}
}
}
Ok(())
}
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