Skip to content

Commit

Permalink
Refactor bert-convert and BertTerm::write_as_bert
Browse files Browse the repository at this point in the history
  • Loading branch information
@gnuvince
gnuvince committed Sep 2, 2018
1 parent 4e6400f commit 56c7ae9
Show file tree
Hide file tree
Showing 2 changed files with 69 additions and 79 deletions.
136 changes: 63 additions & 73 deletions src/bertterm.rs
View file
Original file line number Diff line number Diff line change
Expand Up @@ -3,6 +3,7 @@ extern crate itoa;
use std::io;
use std::iter;

use byteorder::{BigEndian, WriteBytesExt};
use num_bigint::{BigInt, Sign};

use consts::*;
Expand Down Expand Up @@ -114,6 +115,15 @@ impl BertTerm {
let () = JsonPrettyPrinter::new(&self, transform_prolists).write(w)?;
Ok(())
}

/// Writes a `BertTerm` into `W` encoded using Erlang's [External Term Format].
///
/// [External Term Format]: http://erlang.org/doc/apps/erts/erl_ext_dist.html
pub fn write_as_bert<W: io::Write>(&self, w: &mut W) -> Result<()> {
BertWriter::new(&self).write(w)?;
return Ok(());
}

}

struct ErlangPrettyPrinter<'a> {
Expand Down Expand Up @@ -347,125 +357,105 @@ fn must_be_escaped(b: u8) -> bool {
b == b'"' || b == b'\\'
}

struct BertWriter<'a> {
term: &'a BertTerm
}

impl BertTerm {
pub fn write_bert(&self) -> Vec<u8> {
let mut out: Vec<u8> = Vec::with_capacity(4096);
out.push(BERT_MAGIC_NUMBER);
self.dump_bert(&mut out);
return out;
impl <'a> BertWriter<'a> {
fn new(term: &'a BertTerm) -> Self {
BertWriter { term }
}

fn dump_bert(&self, out: &mut Vec<u8>) {
match *self {
BertTerm::Nil => out.push(NIL_EXT),
fn write<W: io::Write>(&self, w: &mut W) -> Result<()> {
w.write_u8(BERT_MAGIC_NUMBER)?;
self.write_bert(&self.term, w)?;
return Ok(());
}

fn write_bert<W: io::Write>(&self, term: &BertTerm, w: &mut W) -> io::Result<()> {
match *term {
BertTerm::Nil => w.write_u8(NIL_EXT),
BertTerm::Int(n) => {
if n >= 0 && n < 256 {
out.push(SMALL_INTEGER_EXT);
out.push(n as u8);
w.write_u8(SMALL_INTEGER_EXT)?;
w.write_u8(n as u8)
} else {
out.push(INTEGER_EXT);
out.push( ((n >> 24) & 0xff) as u8 );
out.push( ((n >> 16) & 0xff) as u8 );
out.push( ((n >> 8) & 0xff) as u8 );
out.push( (n & 0xff) as u8 );
w.write_u8(INTEGER_EXT)?;
w.write_i32::<BigEndian>(n)
}
}
BertTerm::BigInt(ref b) => {
let (sign, bytes) = b.to_bytes_le();
let len = bytes.len();
if len < 256 {
out.push(SMALL_BIG_EXT);
out.push(len as u8);
w.write_u8(SMALL_BIG_EXT)?;
w.write_u8(len as u8)?;
} else {
out.push(LARGE_BIG_EXT);
out.push( ((len >> 24) & 0xff) as u8 );
out.push( ((len >> 16) & 0xff) as u8 );
out.push( ((len >> 8) & 0xff) as u8 );
out.push( (len & 0xff) as u8 );
w.write_u8(LARGE_BIG_EXT)?;
w.write_u32::<BigEndian>(len as u32)?;
}
if sign == Sign::Minus {
out.push(1);
w.write_u8(1)?;
} else {
out.push(0);
w.write_u8(0)?;
}
out.extend(bytes);
w.write_all(&bytes)
}
BertTerm::Float(f) => {
let n = f.to_bits();
out.push(NEW_FLOAT_EXT);
out.push( ((n >> 56) & 0xff) as u8 );
out.push( ((n >> 48) & 0xff) as u8 );
out.push( ((n >> 40) & 0xff) as u8 );
out.push( ((n >> 32) & 0xff) as u8 );
out.push( ((n >> 24) & 0xff) as u8 );
out.push( ((n >> 16) & 0xff) as u8 );
out.push( ((n >> 8) & 0xff) as u8 );
out.push( (n & 0xff) as u8 );
w.write_u8(NEW_FLOAT_EXT)?;
w.write_f64::<BigEndian>(f)
}
BertTerm::Tuple(ref terms) => {
let len = terms.len();
if len < 256 {
out.push(SMALL_TUPLE_EXT);
out.push(len as u8);
w.write_u8(SMALL_TUPLE_EXT)?;
w.write_u8(len as u8)?;
} else {
out.push(LARGE_TUPLE_EXT);
out.push( ((len >> 24) & 0xff) as u8 );
out.push( ((len >> 16) & 0xff) as u8 );
out.push( ((len >> 8) & 0xff) as u8 );
out.push( (len & 0xff) as u8 );
w.write_u8(LARGE_TUPLE_EXT)?;
w.write_u32::<BigEndian>(len as u32)?;
}
for t in terms {
t.dump_bert(out);
self.write_bert(t, w)?;
}
Ok(())
}
BertTerm::List(ref terms) => {
let len = terms.len();
out.push(LIST_EXT);
out.push( ((len >> 24) & 0xff) as u8 );
out.push( ((len >> 16) & 0xff) as u8 );
out.push( ((len >> 8) & 0xff) as u8 );
out.push( (len & 0xff) as u8 );
w.write_u8(LIST_EXT)?;
w.write_u32::<BigEndian>(len as u32)?;
for t in terms {
t.dump_bert(out);
self.write_bert(t, w)?;
}
out.push(NIL_EXT);
w.write_u8(NIL_EXT)
}
BertTerm::Map(ref keys, ref vals) => {
let len = keys.len();
out.push(MAP_EXT);
out.push( ((len >> 24) & 0xff) as u8 );
out.push( ((len >> 16) & 0xff) as u8 );
out.push( ((len >> 8) & 0xff) as u8 );
out.push( (len & 0xff) as u8 );
w.write_u8(MAP_EXT)?;
w.write_u32::<BigEndian>(len as u32)?;
for (k, v) in keys.iter().zip(vals) {
k.dump_bert(out);
v.dump_bert(out);
self.write_bert(k, w)?;
self.write_bert(v, w)?;
}
Ok(())
}
BertTerm::Atom(ref chars) => {
let bytes = chars.bytes();
let bytes = chars.as_bytes();
let len = bytes.len();
out.push(ATOM_UTF8_EXT);
out.push( ((len >> 8) & 0xff) as u8 );
out.push( (len & 0xff) as u8 );
out.extend(bytes);
w.write_u8(ATOM_UTF8_EXT)?;
w.write_u16::<BigEndian>(len as u16)?;
w.write_all(bytes)
}
BertTerm::String(ref bytes) => {
let len = bytes.len();
out.push(STRING_EXT);
out.push( ((len >> 8) & 0xff) as u8 );
out.push( (len & 0xff) as u8 );
out.extend(bytes);
w.write_u8(STRING_EXT)?;
w.write_u16::<BigEndian>(len as u16)?;
w.write_all(bytes)
}
BertTerm::Binary(ref bytes) => {
let len = bytes.len();
out.push(BINARY_EXT);
out.push( ((len >> 24) & 0xff) as u8 );
out.push( ((len >> 16) & 0xff) as u8 );
out.push( ((len >> 8) & 0xff) as u8 );
out.push( (len & 0xff) as u8 );
out.extend(bytes);
w.write_u8(BINARY_EXT)?;
w.write_u32::<BigEndian>(len as u32)?;
w.write_all(bytes)
}
}
}
Expand Down
12 changes: 6 additions & 6 deletions src/convert.rs
View file
Original file line number Diff line number Diff line change
Expand Up @@ -6,7 +6,7 @@ use clap::{Arg, App};
use rayon::prelude::*;

use std::io::{self, Read, Write, BufWriter};
use std::fs::File;
use std::fs::{self, File};
use std::path::PathBuf;
use std::process::exit;
use std::time::Instant;
Expand Down Expand Up @@ -74,8 +74,7 @@ fn handle(file: &str, verbose: bool, output_dir: &PathBuf) -> Result<(), BertErr
let mut stdin = io::stdin();
stdin.read_to_end(&mut buf)?;
} else {
let mut f = File::open(file)?;
f.read_to_end(&mut buf)?;
buf = fs::read(file)?;
}

let top = Instant::now();
Expand Down Expand Up @@ -112,9 +111,10 @@ fn create_bert2_file(term: BertTerm, output_dir: &PathBuf) -> Result<(), BertErr
let f = File::create(path)?;
let mut stream = BufWriter::new(f);
for item in items {
let item_bert = item.write_bert();
stream.write_all(&usize_to_leb128(item_bert.len()))?;
stream.write_all(&item_bert)?;
let mut bytes = Vec::with_capacity(4096);
item.write_as_bert(&mut bytes)?;
stream.write_all(&usize_to_leb128(bytes.len()))?;
stream.write_all(&bytes)?;
}
} else {
return Err(BertError::NotABertFile);
Expand Down

0 comments on commit 56c7ae9

Please sign in to comment.