1120 lines
35 KiB
Rust
1120 lines
35 KiB
Rust
// Copyright 2012-2014 The Rust Project Developers. See the COPYRIGHT
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// file at the top-level directory of this distribution and at
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// http://rust-lang.org/COPYRIGHT.
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//
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// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
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// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
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// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
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// option. This file may not be copied, modified, or distributed
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// except according to those terms.
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#[allow(missing_doc)];
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use std::str;
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macro_rules! try( ($e:expr) => (
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match $e { Ok(e) => e, Err(e) => { self.last_error = Err(e); return } }
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) )
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// Simple Extensible Binary Markup Language (ebml) reader and writer on a
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// cursor model. See the specification here:
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// http://www.matroska.org/technical/specs/rfc/index.html
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// Common data structures
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#[deriving(Clone)]
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pub struct Doc<'a> {
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data: &'a [u8],
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start: uint,
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end: uint,
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}
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impl<'doc> Doc<'doc> {
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pub fn get<'a>(&'a self, tag: uint) -> Doc<'a> {
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reader::get_doc(*self, tag)
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}
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pub fn as_str_slice<'a>(&'a self) -> &'a str {
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str::from_utf8(self.data.slice(self.start, self.end)).unwrap()
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}
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pub fn as_str(&self) -> ~str {
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self.as_str_slice().to_owned()
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}
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}
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pub struct TaggedDoc<'a> {
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priv tag: uint,
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doc: Doc<'a>,
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}
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pub enum EbmlEncoderTag {
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EsUint, // 0
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EsU64, // 1
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EsU32, // 2
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EsU16, // 3
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EsU8, // 4
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EsInt, // 5
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EsI64, // 6
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EsI32, // 7
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EsI16, // 8
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EsI8, // 9
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EsBool, // 10
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EsChar, // 11
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EsStr, // 12
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EsF64, // 13
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EsF32, // 14
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EsFloat, // 15
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EsEnum, // 16
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EsEnumVid, // 17
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EsEnumBody, // 18
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EsVec, // 19
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EsVecLen, // 20
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EsVecElt, // 21
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EsMap, // 22
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EsMapLen, // 23
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EsMapKey, // 24
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EsMapVal, // 25
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EsOpaque,
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EsLabel, // Used only when debugging
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}
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// --------------------------------------
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pub mod reader {
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use std::char;
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use std::cast::transmute;
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use std::int;
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use std::option::{None, Option, Some};
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use std::io::extensions::u64_from_be_bytes;
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use serialize;
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use super::{ EsVec, EsMap, EsEnum, EsVecLen, EsVecElt, EsMapLen, EsMapKey,
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EsEnumVid, EsU64, EsU32, EsU16, EsU8, EsInt, EsI64, EsI32, EsI16, EsI8,
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EsBool, EsF64, EsF32, EsChar, EsStr, EsMapVal, EsEnumBody, EsUint,
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EsOpaque, EsLabel, EbmlEncoderTag, Doc, TaggedDoc };
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// ebml reading
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pub struct Res {
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val: uint,
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next: uint
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}
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#[inline(never)]
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fn vuint_at_slow(data: &[u8], start: uint) -> Res {
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let a = data[start];
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if a & 0x80u8 != 0u8 {
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return Res {val: (a & 0x7fu8) as uint, next: start + 1u};
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}
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if a & 0x40u8 != 0u8 {
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return Res {val: ((a & 0x3fu8) as uint) << 8u |
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(data[start + 1u] as uint),
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next: start + 2u};
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}
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if a & 0x20u8 != 0u8 {
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return Res {val: ((a & 0x1fu8) as uint) << 16u |
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(data[start + 1u] as uint) << 8u |
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(data[start + 2u] as uint),
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next: start + 3u};
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}
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if a & 0x10u8 != 0u8 {
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return Res {val: ((a & 0x0fu8) as uint) << 24u |
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(data[start + 1u] as uint) << 16u |
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(data[start + 2u] as uint) << 8u |
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(data[start + 3u] as uint),
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next: start + 4u};
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}
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fail!("vint too big");
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}
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pub fn vuint_at(data: &[u8], start: uint) -> Res {
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use std::mem::from_be32;
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if data.len() - start < 4 {
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return vuint_at_slow(data, start);
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}
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// Lookup table for parsing EBML Element IDs as per http://ebml.sourceforge.net/specs/
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// The Element IDs are parsed by reading a big endian u32 positioned at data[start].
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// Using the four most significant bits of the u32 we lookup in the table below how the
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// element ID should be derived from it.
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//
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// The table stores tuples (shift, mask) where shift is the number the u32 should be right
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// shifted with and mask is the value the right shifted value should be masked with.
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// If for example the most significant bit is set this means it's a class A ID and the u32
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// should be right shifted with 24 and masked with 0x7f. Therefore we store (24, 0x7f) at
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// index 0x8 - 0xF (four bit numbers where the most significant bit is set).
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//
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// By storing the number of shifts and masks in a table instead of checking in order if
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// the most significant bit is set, the second most significant bit is set etc. we can
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// replace up to three "and+branch" with a single table lookup which gives us a measured
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// speedup of around 2x on x86_64.
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static SHIFT_MASK_TABLE: [(u32, u32), ..16] = [
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(0, 0x0), (0, 0x0fffffff),
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(8, 0x1fffff), (8, 0x1fffff),
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(16, 0x3fff), (16, 0x3fff), (16, 0x3fff), (16, 0x3fff),
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(24, 0x7f), (24, 0x7f), (24, 0x7f), (24, 0x7f),
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(24, 0x7f), (24, 0x7f), (24, 0x7f), (24, 0x7f)
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];
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unsafe {
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let ptr = data.as_ptr().offset(start as int) as *i32;
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let val = from_be32(*ptr) as u32;
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let i = (val >> 28u) as uint;
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let (shift, mask) = SHIFT_MASK_TABLE[i];
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Res {
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val: ((val >> shift) & mask) as uint,
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next: start + (((32 - shift) >> 3) as uint)
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}
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}
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}
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pub fn Doc<'a>(data: &'a [u8]) -> Doc<'a> {
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Doc { data: data, start: 0u, end: data.len() }
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}
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pub fn doc_at<'a>(data: &'a [u8], start: uint) -> TaggedDoc<'a> {
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let elt_tag = vuint_at(data, start);
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let elt_size = vuint_at(data, elt_tag.next);
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let end = elt_size.next + elt_size.val;
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TaggedDoc {
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tag: elt_tag.val,
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doc: Doc { data: data, start: elt_size.next, end: end }
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}
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}
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pub fn maybe_get_doc<'a>(d: Doc<'a>, tg: uint) -> Option<Doc<'a>> {
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let mut pos = d.start;
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while pos < d.end {
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let elt_tag = vuint_at(d.data, pos);
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let elt_size = vuint_at(d.data, elt_tag.next);
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pos = elt_size.next + elt_size.val;
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if elt_tag.val == tg {
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return Some(Doc { data: d.data, start: elt_size.next,
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end: pos });
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}
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}
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None
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}
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pub fn get_doc<'a>(d: Doc<'a>, tg: uint) -> Doc<'a> {
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match maybe_get_doc(d, tg) {
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Some(d) => d,
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None => {
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error!("failed to find block with tag {}", tg);
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fail!();
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}
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}
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}
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pub fn docs<'a>(d: Doc<'a>, it: |uint, Doc<'a>| -> bool) -> bool {
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let mut pos = d.start;
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while pos < d.end {
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let elt_tag = vuint_at(d.data, pos);
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let elt_size = vuint_at(d.data, elt_tag.next);
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pos = elt_size.next + elt_size.val;
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let doc = Doc { data: d.data, start: elt_size.next, end: pos };
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if !it(elt_tag.val, doc) {
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return false;
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}
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}
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return true;
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}
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pub fn tagged_docs<'a>(d: Doc<'a>, tg: uint, it: |Doc<'a>| -> bool) -> bool {
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let mut pos = d.start;
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while pos < d.end {
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let elt_tag = vuint_at(d.data, pos);
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let elt_size = vuint_at(d.data, elt_tag.next);
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pos = elt_size.next + elt_size.val;
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if elt_tag.val == tg {
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let doc = Doc { data: d.data, start: elt_size.next,
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end: pos };
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if !it(doc) {
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return false;
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}
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}
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}
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return true;
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}
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pub fn with_doc_data<'a, T>(d: Doc<'a>, f: |x: &'a [u8]| -> T) -> T {
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f(d.data.slice(d.start, d.end))
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}
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pub fn doc_as_u8(d: Doc) -> u8 {
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assert_eq!(d.end, d.start + 1u);
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d.data[d.start]
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}
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pub fn doc_as_u16(d: Doc) -> u16 {
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assert_eq!(d.end, d.start + 2u);
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u64_from_be_bytes(d.data, d.start, 2u) as u16
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}
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pub fn doc_as_u32(d: Doc) -> u32 {
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assert_eq!(d.end, d.start + 4u);
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u64_from_be_bytes(d.data, d.start, 4u) as u32
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}
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pub fn doc_as_u64(d: Doc) -> u64 {
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assert_eq!(d.end, d.start + 8u);
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u64_from_be_bytes(d.data, d.start, 8u)
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}
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pub fn doc_as_i8(d: Doc) -> i8 { doc_as_u8(d) as i8 }
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pub fn doc_as_i16(d: Doc) -> i16 { doc_as_u16(d) as i16 }
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pub fn doc_as_i32(d: Doc) -> i32 { doc_as_u32(d) as i32 }
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pub fn doc_as_i64(d: Doc) -> i64 { doc_as_u64(d) as i64 }
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pub struct Decoder<'a> {
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priv parent: Doc<'a>,
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priv pos: uint,
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}
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pub fn Decoder<'a>(d: Doc<'a>) -> Decoder<'a> {
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Decoder {
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parent: d,
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pos: d.start
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}
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}
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impl<'doc> Decoder<'doc> {
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fn _check_label(&mut self, lbl: &str) {
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if self.pos < self.parent.end {
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let TaggedDoc { tag: r_tag, doc: r_doc } =
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doc_at(self.parent.data, self.pos);
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if r_tag == (EsLabel as uint) {
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self.pos = r_doc.end;
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let str = r_doc.as_str_slice();
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if lbl != str {
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fail!("Expected label {} but found {}", lbl, str);
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}
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}
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}
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}
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fn next_doc(&mut self, exp_tag: EbmlEncoderTag) -> Doc<'doc> {
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debug!(". next_doc(exp_tag={:?})", exp_tag);
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if self.pos >= self.parent.end {
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fail!("no more documents in current node!");
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}
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let TaggedDoc { tag: r_tag, doc: r_doc } =
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doc_at(self.parent.data, self.pos);
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debug!("self.parent={}-{} self.pos={} r_tag={} r_doc={}-{}",
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self.parent.start,
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self.parent.end,
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self.pos,
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r_tag,
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r_doc.start,
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r_doc.end);
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if r_tag != (exp_tag as uint) {
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fail!("expected EBML doc with tag {:?} but found tag {:?}",
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exp_tag, r_tag);
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}
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if r_doc.end > self.parent.end {
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fail!("invalid EBML, child extends to {:#x}, parent to {:#x}",
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r_doc.end, self.parent.end);
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}
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self.pos = r_doc.end;
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r_doc
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}
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fn push_doc<T>(&mut self, exp_tag: EbmlEncoderTag,
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f: |&mut Decoder<'doc>| -> T) -> T {
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let d = self.next_doc(exp_tag);
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let old_parent = self.parent;
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let old_pos = self.pos;
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self.parent = d;
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self.pos = d.start;
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let r = f(self);
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self.parent = old_parent;
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self.pos = old_pos;
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r
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}
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fn _next_uint(&mut self, exp_tag: EbmlEncoderTag) -> uint {
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let r = doc_as_u32(self.next_doc(exp_tag));
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debug!("_next_uint exp_tag={:?} result={}", exp_tag, r);
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r as uint
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}
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pub fn read_opaque<R>(&mut self, op: |&mut Decoder<'doc>, Doc| -> R) -> R {
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let doc = self.next_doc(EsOpaque);
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let (old_parent, old_pos) = (self.parent, self.pos);
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self.parent = doc;
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self.pos = doc.start;
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let result = op(self, doc);
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self.parent = old_parent;
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self.pos = old_pos;
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result
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}
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}
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impl<'doc> serialize::Decoder for Decoder<'doc> {
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fn read_nil(&mut self) -> () { () }
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fn read_u64(&mut self) -> u64 { doc_as_u64(self.next_doc(EsU64)) }
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fn read_u32(&mut self) -> u32 { doc_as_u32(self.next_doc(EsU32)) }
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fn read_u16(&mut self) -> u16 { doc_as_u16(self.next_doc(EsU16)) }
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fn read_u8 (&mut self) -> u8 { doc_as_u8 (self.next_doc(EsU8 )) }
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fn read_uint(&mut self) -> uint {
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let v = doc_as_u64(self.next_doc(EsUint));
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if v > (::std::uint::MAX as u64) {
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fail!("uint {} too large for this architecture", v);
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}
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v as uint
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}
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fn read_i64(&mut self) -> i64 {
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doc_as_u64(self.next_doc(EsI64)) as i64
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}
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fn read_i32(&mut self) -> i32 {
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doc_as_u32(self.next_doc(EsI32)) as i32
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}
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fn read_i16(&mut self) -> i16 {
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doc_as_u16(self.next_doc(EsI16)) as i16
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}
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fn read_i8 (&mut self) -> i8 {
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doc_as_u8(self.next_doc(EsI8 )) as i8
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}
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fn read_int(&mut self) -> int {
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let v = doc_as_u64(self.next_doc(EsInt)) as i64;
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if v > (int::MAX as i64) || v < (int::MIN as i64) {
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debug!("FIXME \\#6122: Removing this makes this function miscompile");
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fail!("int {} out of range for this architecture", v);
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}
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v as int
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}
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fn read_bool(&mut self) -> bool {
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doc_as_u8(self.next_doc(EsBool)) != 0
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}
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fn read_f64(&mut self) -> f64 {
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let bits = doc_as_u64(self.next_doc(EsF64));
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unsafe { transmute(bits) }
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}
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fn read_f32(&mut self) -> f32 {
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let bits = doc_as_u32(self.next_doc(EsF32));
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unsafe { transmute(bits) }
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}
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fn read_char(&mut self) -> char {
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char::from_u32(doc_as_u32(self.next_doc(EsChar))).unwrap()
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}
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fn read_str(&mut self) -> ~str {
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self.next_doc(EsStr).as_str()
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}
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// Compound types:
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fn read_enum<T>(&mut self, name: &str, f: |&mut Decoder<'doc>| -> T) -> T {
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debug!("read_enum({})", name);
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self._check_label(name);
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let doc = self.next_doc(EsEnum);
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let (old_parent, old_pos) = (self.parent, self.pos);
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self.parent = doc;
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self.pos = self.parent.start;
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let result = f(self);
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self.parent = old_parent;
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self.pos = old_pos;
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result
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}
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fn read_enum_variant<T>(&mut self,
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_: &[&str],
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f: |&mut Decoder<'doc>, uint| -> T)
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-> T {
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debug!("read_enum_variant()");
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let idx = self._next_uint(EsEnumVid);
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debug!(" idx={}", idx);
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let doc = self.next_doc(EsEnumBody);
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let (old_parent, old_pos) = (self.parent, self.pos);
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self.parent = doc;
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self.pos = self.parent.start;
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let result = f(self, idx);
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self.parent = old_parent;
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self.pos = old_pos;
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result
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}
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fn read_enum_variant_arg<T>(&mut self,
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idx: uint,
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f: |&mut Decoder<'doc>| -> T) -> T {
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debug!("read_enum_variant_arg(idx={})", idx);
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f(self)
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}
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fn read_enum_struct_variant<T>(&mut self,
|
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_: &[&str],
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f: |&mut Decoder<'doc>, uint| -> T)
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-> T {
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debug!("read_enum_struct_variant()");
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let idx = self._next_uint(EsEnumVid);
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debug!(" idx={}", idx);
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let doc = self.next_doc(EsEnumBody);
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let (old_parent, old_pos) = (self.parent, self.pos);
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self.parent = doc;
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self.pos = self.parent.start;
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|
|
let result = f(self, idx);
|
|
|
|
self.parent = old_parent;
|
|
self.pos = old_pos;
|
|
result
|
|
}
|
|
|
|
fn read_enum_struct_variant_field<T>(&mut self,
|
|
name: &str,
|
|
idx: uint,
|
|
f: |&mut Decoder<'doc>| -> T)
|
|
-> T {
|
|
debug!("read_enum_struct_variant_arg(name={}, idx={})", name, idx);
|
|
f(self)
|
|
}
|
|
|
|
fn read_struct<T>(&mut self,
|
|
name: &str,
|
|
_: uint,
|
|
f: |&mut Decoder<'doc>| -> T)
|
|
-> T {
|
|
debug!("read_struct(name={})", name);
|
|
f(self)
|
|
}
|
|
|
|
fn read_struct_field<T>(&mut self,
|
|
name: &str,
|
|
idx: uint,
|
|
f: |&mut Decoder<'doc>| -> T)
|
|
-> T {
|
|
debug!("read_struct_field(name={}, idx={})", name, idx);
|
|
self._check_label(name);
|
|
f(self)
|
|
}
|
|
|
|
fn read_tuple<T>(&mut self, f: |&mut Decoder<'doc>, uint| -> T) -> T {
|
|
debug!("read_tuple()");
|
|
self.read_seq(f)
|
|
}
|
|
|
|
fn read_tuple_arg<T>(&mut self, idx: uint, f: |&mut Decoder<'doc>| -> T)
|
|
-> T {
|
|
debug!("read_tuple_arg(idx={})", idx);
|
|
self.read_seq_elt(idx, f)
|
|
}
|
|
|
|
fn read_tuple_struct<T>(&mut self,
|
|
name: &str,
|
|
f: |&mut Decoder<'doc>, uint| -> T)
|
|
-> T {
|
|
debug!("read_tuple_struct(name={})", name);
|
|
self.read_tuple(f)
|
|
}
|
|
|
|
fn read_tuple_struct_arg<T>(&mut self,
|
|
idx: uint,
|
|
f: |&mut Decoder<'doc>| -> T)
|
|
-> T {
|
|
debug!("read_tuple_struct_arg(idx={})", idx);
|
|
self.read_tuple_arg(idx, f)
|
|
}
|
|
|
|
fn read_option<T>(&mut self, f: |&mut Decoder<'doc>, bool| -> T) -> T {
|
|
debug!("read_option()");
|
|
self.read_enum("Option", |this| {
|
|
this.read_enum_variant(["None", "Some"], |this, idx| {
|
|
match idx {
|
|
0 => f(this, false),
|
|
1 => f(this, true),
|
|
_ => fail!(),
|
|
}
|
|
})
|
|
})
|
|
}
|
|
|
|
fn read_seq<T>(&mut self, f: |&mut Decoder<'doc>, uint| -> T) -> T {
|
|
debug!("read_seq()");
|
|
self.push_doc(EsVec, |d| {
|
|
let len = d._next_uint(EsVecLen);
|
|
debug!(" len={}", len);
|
|
f(d, len)
|
|
})
|
|
}
|
|
|
|
fn read_seq_elt<T>(&mut self, idx: uint, f: |&mut Decoder<'doc>| -> T)
|
|
-> T {
|
|
debug!("read_seq_elt(idx={})", idx);
|
|
self.push_doc(EsVecElt, f)
|
|
}
|
|
|
|
fn read_map<T>(&mut self, f: |&mut Decoder<'doc>, uint| -> T) -> T {
|
|
debug!("read_map()");
|
|
self.push_doc(EsMap, |d| {
|
|
let len = d._next_uint(EsMapLen);
|
|
debug!(" len={}", len);
|
|
f(d, len)
|
|
})
|
|
}
|
|
|
|
fn read_map_elt_key<T>(&mut self, idx: uint, f: |&mut Decoder<'doc>| -> T)
|
|
-> T {
|
|
debug!("read_map_elt_key(idx={})", idx);
|
|
self.push_doc(EsMapKey, f)
|
|
}
|
|
|
|
fn read_map_elt_val<T>(&mut self, idx: uint, f: |&mut Decoder<'doc>| -> T)
|
|
-> T {
|
|
debug!("read_map_elt_val(idx={})", idx);
|
|
self.push_doc(EsMapVal, f)
|
|
}
|
|
}
|
|
}
|
|
|
|
pub mod writer {
|
|
use std::cast;
|
|
use std::clone::Clone;
|
|
use std::io;
|
|
use std::io::{Writer, Seek};
|
|
use std::io::MemWriter;
|
|
use std::io::extensions::u64_to_be_bytes;
|
|
|
|
use super::{ EsVec, EsMap, EsEnum, EsVecLen, EsVecElt, EsMapLen, EsMapKey,
|
|
EsEnumVid, EsU64, EsU32, EsU16, EsU8, EsInt, EsI64, EsI32, EsI16, EsI8,
|
|
EsBool, EsF64, EsF32, EsChar, EsStr, EsMapVal, EsEnumBody, EsUint,
|
|
EsOpaque, EsLabel, EbmlEncoderTag };
|
|
|
|
use serialize;
|
|
|
|
// ebml writing
|
|
pub struct Encoder<'a> {
|
|
// FIXME(#5665): this should take a trait object. Note that if you
|
|
// delete this comment you should consider removing the
|
|
// unwrap()'s below of the results of the calls to
|
|
// write(). We're guaranteed that writing into a MemWriter
|
|
// won't fail, but this is not true for all I/O streams in
|
|
// general.
|
|
writer: &'a mut MemWriter,
|
|
priv size_positions: ~[uint],
|
|
last_error: io::IoResult<()>,
|
|
}
|
|
|
|
fn write_sized_vuint(w: &mut MemWriter, n: uint, size: uint) {
|
|
match size {
|
|
1u => w.write(&[0x80u8 | (n as u8)]),
|
|
2u => w.write(&[0x40u8 | ((n >> 8_u) as u8), n as u8]),
|
|
3u => w.write(&[0x20u8 | ((n >> 16_u) as u8), (n >> 8_u) as u8,
|
|
n as u8]),
|
|
4u => w.write(&[0x10u8 | ((n >> 24_u) as u8), (n >> 16_u) as u8,
|
|
(n >> 8_u) as u8, n as u8]),
|
|
_ => fail!("vint to write too big: {}", n)
|
|
}.unwrap()
|
|
}
|
|
|
|
fn write_vuint(w: &mut MemWriter, n: uint) {
|
|
if n < 0x7f_u { write_sized_vuint(w, n, 1u); return; }
|
|
if n < 0x4000_u { write_sized_vuint(w, n, 2u); return; }
|
|
if n < 0x200000_u { write_sized_vuint(w, n, 3u); return; }
|
|
if n < 0x10000000_u { write_sized_vuint(w, n, 4u); return; }
|
|
fail!("vint to write too big: {}", n);
|
|
}
|
|
|
|
pub fn Encoder<'a>(w: &'a mut MemWriter) -> Encoder<'a> {
|
|
let size_positions: ~[uint] = ~[];
|
|
Encoder {
|
|
writer: w,
|
|
size_positions: size_positions,
|
|
last_error: Ok(()),
|
|
}
|
|
}
|
|
|
|
// FIXME (#2741): Provide a function to write the standard ebml header.
|
|
impl<'a> Encoder<'a> {
|
|
/// FIXME(pcwalton): Workaround for badness in trans. DO NOT USE ME.
|
|
pub unsafe fn unsafe_clone(&self) -> Encoder<'a> {
|
|
Encoder {
|
|
writer: cast::transmute_copy(&self.writer),
|
|
size_positions: self.size_positions.clone(),
|
|
last_error: Ok(()),
|
|
}
|
|
}
|
|
|
|
pub fn start_tag(&mut self, tag_id: uint) {
|
|
debug!("Start tag {}", tag_id);
|
|
|
|
// Write the enum ID:
|
|
write_vuint(self.writer, tag_id);
|
|
|
|
// Write a placeholder four-byte size.
|
|
self.size_positions.push(try!(self.writer.tell()) as uint);
|
|
let zeroes: &[u8] = &[0u8, 0u8, 0u8, 0u8];
|
|
try!(self.writer.write(zeroes));
|
|
}
|
|
|
|
pub fn end_tag(&mut self) {
|
|
let last_size_pos = self.size_positions.pop().unwrap();
|
|
let cur_pos = try!(self.writer.tell());
|
|
try!(self.writer.seek(last_size_pos as i64, io::SeekSet));
|
|
let size = cur_pos as uint - last_size_pos - 4;
|
|
write_sized_vuint(self.writer, size, 4u);
|
|
try!(self.writer.seek(cur_pos as i64, io::SeekSet));
|
|
|
|
debug!("End tag (size = {})", size);
|
|
}
|
|
|
|
pub fn wr_tag(&mut self, tag_id: uint, blk: ||) {
|
|
self.start_tag(tag_id);
|
|
blk();
|
|
self.end_tag();
|
|
}
|
|
|
|
pub fn wr_tagged_bytes(&mut self, tag_id: uint, b: &[u8]) {
|
|
write_vuint(self.writer, tag_id);
|
|
write_vuint(self.writer, b.len());
|
|
self.writer.write(b).unwrap();
|
|
}
|
|
|
|
pub fn wr_tagged_u64(&mut self, tag_id: uint, v: u64) {
|
|
u64_to_be_bytes(v, 8u, |v| {
|
|
self.wr_tagged_bytes(tag_id, v);
|
|
})
|
|
}
|
|
|
|
pub fn wr_tagged_u32(&mut self, tag_id: uint, v: u32) {
|
|
u64_to_be_bytes(v as u64, 4u, |v| {
|
|
self.wr_tagged_bytes(tag_id, v);
|
|
})
|
|
}
|
|
|
|
pub fn wr_tagged_u16(&mut self, tag_id: uint, v: u16) {
|
|
u64_to_be_bytes(v as u64, 2u, |v| {
|
|
self.wr_tagged_bytes(tag_id, v);
|
|
})
|
|
}
|
|
|
|
pub fn wr_tagged_u8(&mut self, tag_id: uint, v: u8) {
|
|
self.wr_tagged_bytes(tag_id, &[v]);
|
|
}
|
|
|
|
pub fn wr_tagged_i64(&mut self, tag_id: uint, v: i64) {
|
|
u64_to_be_bytes(v as u64, 8u, |v| {
|
|
self.wr_tagged_bytes(tag_id, v);
|
|
})
|
|
}
|
|
|
|
pub fn wr_tagged_i32(&mut self, tag_id: uint, v: i32) {
|
|
u64_to_be_bytes(v as u64, 4u, |v| {
|
|
self.wr_tagged_bytes(tag_id, v);
|
|
})
|
|
}
|
|
|
|
pub fn wr_tagged_i16(&mut self, tag_id: uint, v: i16) {
|
|
u64_to_be_bytes(v as u64, 2u, |v| {
|
|
self.wr_tagged_bytes(tag_id, v);
|
|
})
|
|
}
|
|
|
|
pub fn wr_tagged_i8(&mut self, tag_id: uint, v: i8) {
|
|
self.wr_tagged_bytes(tag_id, &[v as u8]);
|
|
}
|
|
|
|
pub fn wr_tagged_str(&mut self, tag_id: uint, v: &str) {
|
|
self.wr_tagged_bytes(tag_id, v.as_bytes());
|
|
}
|
|
|
|
pub fn wr_bytes(&mut self, b: &[u8]) {
|
|
debug!("Write {} bytes", b.len());
|
|
self.writer.write(b).unwrap();
|
|
}
|
|
|
|
pub fn wr_str(&mut self, s: &str) {
|
|
debug!("Write str: {}", s);
|
|
self.writer.write(s.as_bytes()).unwrap();
|
|
}
|
|
}
|
|
|
|
// FIXME (#2743): optionally perform "relaxations" on end_tag to more
|
|
// efficiently encode sizes; this is a fixed point iteration
|
|
|
|
// Set to true to generate more debugging in EBML code.
|
|
// Totally lame approach.
|
|
static DEBUG: bool = true;
|
|
|
|
impl<'a> Encoder<'a> {
|
|
// used internally to emit things like the vector length and so on
|
|
fn _emit_tagged_uint(&mut self, t: EbmlEncoderTag, v: uint) {
|
|
assert!(v <= 0xFFFF_FFFF_u);
|
|
self.wr_tagged_u32(t as uint, v as u32);
|
|
}
|
|
|
|
fn _emit_label(&mut self, label: &str) {
|
|
// There are various strings that we have access to, such as
|
|
// the name of a record field, which do not actually appear in
|
|
// the encoded EBML (normally). This is just for
|
|
// efficiency. When debugging, though, we can emit such
|
|
// labels and then they will be checked by decoder to
|
|
// try and check failures more quickly.
|
|
if DEBUG { self.wr_tagged_str(EsLabel as uint, label) }
|
|
}
|
|
|
|
pub fn emit_opaque(&mut self, f: |&mut Encoder|) {
|
|
self.start_tag(EsOpaque as uint);
|
|
f(self);
|
|
self.end_tag();
|
|
}
|
|
}
|
|
|
|
impl<'a> serialize::Encoder for Encoder<'a> {
|
|
fn emit_nil(&mut self) {}
|
|
|
|
fn emit_uint(&mut self, v: uint) {
|
|
self.wr_tagged_u64(EsUint as uint, v as u64);
|
|
}
|
|
fn emit_u64(&mut self, v: u64) {
|
|
self.wr_tagged_u64(EsU64 as uint, v);
|
|
}
|
|
fn emit_u32(&mut self, v: u32) {
|
|
self.wr_tagged_u32(EsU32 as uint, v);
|
|
}
|
|
fn emit_u16(&mut self, v: u16) {
|
|
self.wr_tagged_u16(EsU16 as uint, v);
|
|
}
|
|
fn emit_u8(&mut self, v: u8) {
|
|
self.wr_tagged_u8(EsU8 as uint, v);
|
|
}
|
|
|
|
fn emit_int(&mut self, v: int) {
|
|
self.wr_tagged_i64(EsInt as uint, v as i64);
|
|
}
|
|
fn emit_i64(&mut self, v: i64) {
|
|
self.wr_tagged_i64(EsI64 as uint, v);
|
|
}
|
|
fn emit_i32(&mut self, v: i32) {
|
|
self.wr_tagged_i32(EsI32 as uint, v);
|
|
}
|
|
fn emit_i16(&mut self, v: i16) {
|
|
self.wr_tagged_i16(EsI16 as uint, v);
|
|
}
|
|
fn emit_i8(&mut self, v: i8) {
|
|
self.wr_tagged_i8(EsI8 as uint, v);
|
|
}
|
|
|
|
fn emit_bool(&mut self, v: bool) {
|
|
self.wr_tagged_u8(EsBool as uint, v as u8)
|
|
}
|
|
|
|
fn emit_f64(&mut self, v: f64) {
|
|
let bits = unsafe { cast::transmute(v) };
|
|
self.wr_tagged_u64(EsF64 as uint, bits);
|
|
}
|
|
fn emit_f32(&mut self, v: f32) {
|
|
let bits = unsafe { cast::transmute(v) };
|
|
self.wr_tagged_u32(EsF32 as uint, bits);
|
|
}
|
|
fn emit_char(&mut self, v: char) {
|
|
self.wr_tagged_u32(EsChar as uint, v as u32);
|
|
}
|
|
|
|
fn emit_str(&mut self, v: &str) {
|
|
self.wr_tagged_str(EsStr as uint, v)
|
|
}
|
|
|
|
fn emit_enum(&mut self, name: &str, f: |&mut Encoder<'a>|) {
|
|
self._emit_label(name);
|
|
self.start_tag(EsEnum as uint);
|
|
f(self);
|
|
self.end_tag();
|
|
}
|
|
|
|
fn emit_enum_variant(&mut self,
|
|
_: &str,
|
|
v_id: uint,
|
|
_: uint,
|
|
f: |&mut Encoder<'a>|) {
|
|
self._emit_tagged_uint(EsEnumVid, v_id);
|
|
self.start_tag(EsEnumBody as uint);
|
|
f(self);
|
|
self.end_tag();
|
|
}
|
|
|
|
fn emit_enum_variant_arg(&mut self, _: uint, f: |&mut Encoder<'a>|) {
|
|
f(self)
|
|
}
|
|
|
|
fn emit_enum_struct_variant(&mut self,
|
|
v_name: &str,
|
|
v_id: uint,
|
|
cnt: uint,
|
|
f: |&mut Encoder<'a>|) {
|
|
self.emit_enum_variant(v_name, v_id, cnt, f)
|
|
}
|
|
|
|
fn emit_enum_struct_variant_field(&mut self,
|
|
_: &str,
|
|
idx: uint,
|
|
f: |&mut Encoder<'a>|) {
|
|
self.emit_enum_variant_arg(idx, f)
|
|
}
|
|
|
|
fn emit_struct(&mut self,
|
|
_: &str,
|
|
_len: uint,
|
|
f: |&mut Encoder<'a>|) {
|
|
f(self)
|
|
}
|
|
|
|
fn emit_struct_field(&mut self,
|
|
name: &str,
|
|
_: uint,
|
|
f: |&mut Encoder<'a>|) {
|
|
self._emit_label(name);
|
|
f(self)
|
|
}
|
|
|
|
fn emit_tuple(&mut self, len: uint, f: |&mut Encoder<'a>|) {
|
|
self.emit_seq(len, f)
|
|
}
|
|
fn emit_tuple_arg(&mut self, idx: uint, f: |&mut Encoder<'a>|) {
|
|
self.emit_seq_elt(idx, f)
|
|
}
|
|
|
|
fn emit_tuple_struct(&mut self,
|
|
_: &str,
|
|
len: uint,
|
|
f: |&mut Encoder<'a>|) {
|
|
self.emit_seq(len, f)
|
|
}
|
|
fn emit_tuple_struct_arg(&mut self,
|
|
idx: uint,
|
|
f: |&mut Encoder<'a>|) {
|
|
self.emit_seq_elt(idx, f)
|
|
}
|
|
|
|
fn emit_option(&mut self, f: |&mut Encoder<'a>|) {
|
|
self.emit_enum("Option", f);
|
|
}
|
|
fn emit_option_none(&mut self) {
|
|
self.emit_enum_variant("None", 0, 0, |_| ())
|
|
}
|
|
fn emit_option_some(&mut self, f: |&mut Encoder<'a>|) {
|
|
self.emit_enum_variant("Some", 1, 1, f)
|
|
}
|
|
|
|
fn emit_seq(&mut self, len: uint, f: |&mut Encoder<'a>|) {
|
|
self.start_tag(EsVec as uint);
|
|
self._emit_tagged_uint(EsVecLen, len);
|
|
f(self);
|
|
self.end_tag();
|
|
}
|
|
|
|
fn emit_seq_elt(&mut self, _idx: uint, f: |&mut Encoder<'a>|) {
|
|
self.start_tag(EsVecElt as uint);
|
|
f(self);
|
|
self.end_tag();
|
|
}
|
|
|
|
fn emit_map(&mut self, len: uint, f: |&mut Encoder<'a>|) {
|
|
self.start_tag(EsMap as uint);
|
|
self._emit_tagged_uint(EsMapLen, len);
|
|
f(self);
|
|
self.end_tag();
|
|
}
|
|
|
|
fn emit_map_elt_key(&mut self, _idx: uint, f: |&mut Encoder<'a>|) {
|
|
self.start_tag(EsMapKey as uint);
|
|
f(self);
|
|
self.end_tag();
|
|
}
|
|
|
|
fn emit_map_elt_val(&mut self, _idx: uint, f: |&mut Encoder<'a>|) {
|
|
self.start_tag(EsMapVal as uint);
|
|
f(self);
|
|
self.end_tag();
|
|
}
|
|
}
|
|
}
|
|
|
|
// ___________________________________________________________________________
|
|
// Testing
|
|
|
|
#[cfg(test)]
|
|
mod tests {
|
|
use ebml::reader;
|
|
use ebml::writer;
|
|
use {Encodable, Decodable};
|
|
|
|
use std::io::MemWriter;
|
|
use std::option::{None, Option, Some};
|
|
|
|
#[test]
|
|
fn test_vuint_at() {
|
|
let data = [
|
|
0x80,
|
|
0xff,
|
|
0x40, 0x00,
|
|
0x7f, 0xff,
|
|
0x20, 0x00, 0x00,
|
|
0x3f, 0xff, 0xff,
|
|
0x10, 0x00, 0x00, 0x00,
|
|
0x1f, 0xff, 0xff, 0xff
|
|
];
|
|
|
|
let mut res: reader::Res;
|
|
|
|
// Class A
|
|
res = reader::vuint_at(data, 0);
|
|
assert_eq!(res.val, 0);
|
|
assert_eq!(res.next, 1);
|
|
res = reader::vuint_at(data, res.next);
|
|
assert_eq!(res.val, (1 << 7) - 1);
|
|
assert_eq!(res.next, 2);
|
|
|
|
// Class B
|
|
res = reader::vuint_at(data, res.next);
|
|
assert_eq!(res.val, 0);
|
|
assert_eq!(res.next, 4);
|
|
res = reader::vuint_at(data, res.next);
|
|
assert_eq!(res.val, (1 << 14) - 1);
|
|
assert_eq!(res.next, 6);
|
|
|
|
// Class C
|
|
res = reader::vuint_at(data, res.next);
|
|
assert_eq!(res.val, 0);
|
|
assert_eq!(res.next, 9);
|
|
res = reader::vuint_at(data, res.next);
|
|
assert_eq!(res.val, (1 << 21) - 1);
|
|
assert_eq!(res.next, 12);
|
|
|
|
// Class D
|
|
res = reader::vuint_at(data, res.next);
|
|
assert_eq!(res.val, 0);
|
|
assert_eq!(res.next, 16);
|
|
res = reader::vuint_at(data, res.next);
|
|
assert_eq!(res.val, (1 << 28) - 1);
|
|
assert_eq!(res.next, 20);
|
|
}
|
|
|
|
#[test]
|
|
fn test_option_int() {
|
|
fn test_v(v: Option<int>) {
|
|
debug!("v == {:?}", v);
|
|
let mut wr = MemWriter::new();
|
|
{
|
|
let mut ebml_w = writer::Encoder(&mut wr);
|
|
v.encode(&mut ebml_w);
|
|
}
|
|
let ebml_doc = reader::Doc(wr.get_ref());
|
|
let mut deser = reader::Decoder(ebml_doc);
|
|
let v1 = Decodable::decode(&mut deser);
|
|
debug!("v1 == {:?}", v1);
|
|
assert_eq!(v, v1);
|
|
}
|
|
|
|
test_v(Some(22));
|
|
test_v(None);
|
|
test_v(Some(3));
|
|
}
|
|
}
|
|
|
|
#[cfg(test)]
|
|
mod bench {
|
|
extern crate test;
|
|
use self::test::BenchHarness;
|
|
use ebml::reader;
|
|
|
|
#[bench]
|
|
pub fn vuint_at_A_aligned(bh: &mut BenchHarness) {
|
|
use std::vec;
|
|
let data = vec::from_fn(4*100, |i| {
|
|
match i % 2 {
|
|
0 => 0x80u8,
|
|
_ => i as u8,
|
|
}
|
|
});
|
|
let mut sum = 0u;
|
|
bh.iter(|| {
|
|
let mut i = 0;
|
|
while i < data.len() {
|
|
sum += reader::vuint_at(data, i).val;
|
|
i += 4;
|
|
}
|
|
});
|
|
}
|
|
|
|
#[bench]
|
|
pub fn vuint_at_A_unaligned(bh: &mut BenchHarness) {
|
|
use std::vec;
|
|
let data = vec::from_fn(4*100+1, |i| {
|
|
match i % 2 {
|
|
1 => 0x80u8,
|
|
_ => i as u8
|
|
}
|
|
});
|
|
let mut sum = 0u;
|
|
bh.iter(|| {
|
|
let mut i = 1;
|
|
while i < data.len() {
|
|
sum += reader::vuint_at(data, i).val;
|
|
i += 4;
|
|
}
|
|
});
|
|
}
|
|
|
|
#[bench]
|
|
pub fn vuint_at_D_aligned(bh: &mut BenchHarness) {
|
|
use std::vec;
|
|
let data = vec::from_fn(4*100, |i| {
|
|
match i % 4 {
|
|
0 => 0x10u8,
|
|
3 => i as u8,
|
|
_ => 0u8
|
|
}
|
|
});
|
|
let mut sum = 0u;
|
|
bh.iter(|| {
|
|
let mut i = 0;
|
|
while i < data.len() {
|
|
sum += reader::vuint_at(data, i).val;
|
|
i += 4;
|
|
}
|
|
});
|
|
}
|
|
|
|
#[bench]
|
|
pub fn vuint_at_D_unaligned(bh: &mut BenchHarness) {
|
|
use std::vec;
|
|
let data = vec::from_fn(4*100+1, |i| {
|
|
match i % 4 {
|
|
1 => 0x10u8,
|
|
0 => i as u8,
|
|
_ => 0u8
|
|
}
|
|
});
|
|
let mut sum = 0u;
|
|
bh.iter(|| {
|
|
let mut i = 1;
|
|
while i < data.len() {
|
|
sum += reader::vuint_at(data, i).val;
|
|
i += 4;
|
|
}
|
|
});
|
|
}
|
|
}
|