955 lines
30 KiB
Rust
955 lines
30 KiB
Rust
// Copyright 2012-2013 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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// 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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struct EbmlTag {
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id: uint,
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size: uint,
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}
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struct EbmlState {
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ebml_tag: EbmlTag,
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tag_pos: uint,
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data_pos: uint,
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}
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pub struct Doc {
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data: @~[u8],
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start: uint,
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end: uint,
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}
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pub struct TaggedDoc {
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tag: uint,
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doc: Doc,
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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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EsStr, // 11
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EsF64, // 12
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EsF32, // 13
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EsFloat, // 14
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EsEnum, // 15
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EsEnumVid, // 16
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EsEnumBody, // 17
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EsVec, // 18
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EsVecLen, // 19
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EsVecElt, // 20
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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 ebml::{Doc, EbmlEncoderTag, EsBool, EsEnum, EsEnumBody, EsEnumVid};
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use ebml::{EsI16, EsI32, EsI64, EsI8, EsInt};
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use ebml::{EsLabel, EsOpaque, EsStr, EsU16, EsU32, EsU64, EsU8, EsUint};
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use ebml::{EsVec, EsVecElt, EsVecLen, TaggedDoc};
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use serialize;
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use core::cast::transmute;
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use core::int;
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use core::io;
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use core::ptr::offset;
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use core::str;
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use core::unstable::intrinsics::bswap32;
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use core::vec;
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// ebml reading
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pub impl Doc {
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fn get(&self, tag: uint) -> Doc {
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get_doc(*self, tag)
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}
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}
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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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#[cfg(target_arch = "x86")]
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#[cfg(target_arch = "x86_64")]
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pub fn vuint_at(data: &[u8], start: uint) -> Res {
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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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unsafe {
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let (ptr, _): (*u8, uint) = transmute(data);
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let ptr = offset(ptr, start);
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let ptr: *i32 = transmute(ptr);
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let val = bswap32(*ptr);
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let val: u32 = transmute(val);
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if (val & 0x80000000) != 0 {
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Res {
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val: ((val >> 24) & 0x7f) as uint,
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next: start + 1
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}
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} else if (val & 0x40000000) != 0 {
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Res {
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val: ((val >> 16) & 0x3fff) as uint,
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next: start + 2
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}
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} else if (val & 0x20000000) != 0 {
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Res {
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val: ((val >> 8) & 0x1fffff) as uint,
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next: start + 3
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}
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} else {
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Res {
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val: (val & 0x0fffffff) as uint,
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next: start + 4
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}
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}
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}
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}
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#[cfg(target_arch = "arm")]
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pub fn vuint_at(data: &[u8], start: uint) -> Res {
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vuint_at_slow(data, start)
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}
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pub fn Doc(data: @~[u8]) -> Doc {
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Doc { data: data, start: 0u, end: vec::len::<u8>(*data) }
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}
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pub fn doc_at(data: @~[u8], start: uint) -> TaggedDoc {
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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(d: Doc, tg: uint) -> Option<Doc> {
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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(d: Doc, tg: uint) -> Doc {
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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 %u", 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(d: Doc, it: &fn(uint, Doc) -> 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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break;
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}
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}
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}
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pub fn tagged_docs(d: Doc, tg: uint, it: &fn(Doc) -> 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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break;
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}
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}
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}
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}
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pub fn doc_data(d: Doc) -> ~[u8] {
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vec::slice::<u8>(*d.data, d.start, d.end).to_vec()
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}
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pub fn with_doc_data<T>(d: Doc, f: &fn(x: &[u8]) -> T) -> T {
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f(vec::slice(*d.data, d.start, d.end))
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}
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pub fn doc_as_str(d: Doc) -> ~str { str::from_bytes(doc_data(d)) }
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pub fn doc_as_u8(d: Doc) -> u8 {
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assert!(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!(d.end == d.start + 2u);
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io::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!(d.end == d.start + 4u);
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io::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!(d.end == d.start + 8u);
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io::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 {
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priv parent: Doc,
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priv pos: uint,
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}
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pub fn Decoder(d: Doc) -> Decoder {
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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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priv impl Decoder {
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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 = doc_as_str(r_doc);
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if lbl != str {
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fail!(fmt!("Expected label %s but found %s",
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lbl,
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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 {
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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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copy self.parent.start, copy self.parent.end,
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copy self.pos, r_tag, r_doc.start, r_doc.end);
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if r_tag != (exp_tag as uint) {
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fail!(fmt!("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!(fmt!("invalid EBML, child extends to 0x%x, \
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parent to 0x%x", 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, d: Doc, f: &fn() -> T) -> T {
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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();
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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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}
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pub impl Decoder {
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fn read_opaque<R>(&mut self, op: &fn(&mut Decoder, 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 serialize::Decoder for Decoder {
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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 > (::core::uint::max_value as u64) {
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fail!(fmt!("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_value as i64) || v < (int::min_value as i64) {
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fail!(fmt!("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)) as bool
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}
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fn read_f64(&mut self) -> f64 { fail!(~"read_f64()"); }
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fn read_f32(&mut self) -> f32 { fail!(~"read_f32()"); }
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fn read_float(&mut self) -> float { fail!(~"read_float()"); }
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fn read_char(&mut self) -> char { fail!(~"read_char()"); }
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fn read_str(&mut self) -> ~str { doc_as_str(self.next_doc(EsStr)) }
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// Compound types:
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fn read_enum<T>(&mut self,
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name: &str,
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f: &fn(&mut Decoder) -> T)
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-> T {
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debug!("read_enum(%s)", 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: &fn(&mut Decoder, 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=%u", 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: &fn(&mut Decoder) -> T) -> T {
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debug!("read_enum_variant_arg(idx=%u)", 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: &fn(&mut Decoder, 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=%u", 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_struct_variant_field<T>(&mut self,
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name: &str,
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idx: uint,
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f: &fn(&mut Decoder) -> T)
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-> T {
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debug!("read_enum_struct_variant_arg(name=%?, idx=%u)", name, idx);
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f(self)
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}
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fn read_struct<T>(&mut self,
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name: &str,
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_: uint,
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f: &fn(&mut Decoder) -> T)
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-> T {
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debug!("read_struct(name=%s)", name);
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f(self)
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}
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fn read_struct_field<T>(&mut self,
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name: &str,
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idx: uint,
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f: &fn(&mut Decoder) -> T)
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-> T {
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debug!("read_struct_field(name=%?, idx=%u)", name, idx);
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self._check_label(name);
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f(self)
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}
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fn read_tuple<T>(&mut self, f: &fn(&mut Decoder, uint) -> T) -> T {
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debug!("read_tuple()");
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self.read_seq(f)
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}
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fn read_tuple_arg<T>(&mut self, idx: uint, f: &fn(&mut Decoder) -> T)
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-> T {
|
|
debug!("read_tuple_arg(idx=%u)", idx);
|
|
self.read_seq_elt(idx, f)
|
|
}
|
|
|
|
fn read_tuple_struct<T>(&mut self,
|
|
name: &str,
|
|
f: &fn(&mut Decoder, uint) -> T)
|
|
-> T {
|
|
debug!("read_tuple_struct(name=%?)", name);
|
|
self.read_tuple(f)
|
|
}
|
|
|
|
fn read_tuple_struct_arg<T>(&mut self,
|
|
idx: uint,
|
|
f: &fn(&mut Decoder) -> T)
|
|
-> T {
|
|
debug!("read_tuple_struct_arg(idx=%u)", idx);
|
|
self.read_tuple_arg(idx, f)
|
|
}
|
|
|
|
fn read_option<T>(&mut self, f: &fn(&mut Decoder, bool) -> T) -> T {
|
|
debug!("read_option()");
|
|
do self.read_enum("Option") |this| {
|
|
do 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: &fn(&mut Decoder, uint) -> T) -> T {
|
|
debug!("read_seq()");
|
|
let doc = self.next_doc(EsVec);
|
|
|
|
let (old_parent, old_pos) = (self.parent, self.pos);
|
|
self.parent = doc;
|
|
self.pos = self.parent.start;
|
|
|
|
let len = self._next_uint(EsVecLen);
|
|
debug!(" len=%u", len);
|
|
let result = f(self, len);
|
|
|
|
self.parent = old_parent;
|
|
self.pos = old_pos;
|
|
result
|
|
}
|
|
|
|
fn read_seq_elt<T>(&mut self, idx: uint, f: &fn(&mut Decoder) -> T)
|
|
-> T {
|
|
debug!("read_seq_elt(idx=%u)", idx);
|
|
let doc = self.next_doc(EsVecElt);
|
|
|
|
let (old_parent, old_pos) = (self.parent, self.pos);
|
|
self.parent = doc;
|
|
self.pos = self.parent.start;
|
|
|
|
let result = f(self);
|
|
|
|
self.parent = old_parent;
|
|
self.pos = old_pos;
|
|
result
|
|
}
|
|
|
|
fn read_map<T>(&mut self, _: &fn(&mut Decoder, uint) -> T) -> T {
|
|
debug!("read_map()");
|
|
fail!(~"read_map is unimplemented");
|
|
}
|
|
|
|
fn read_map_elt_key<T>(&mut self,
|
|
idx: uint,
|
|
_: &fn(&mut Decoder) -> T)
|
|
-> T {
|
|
debug!("read_map_elt_key(idx=%u)", idx);
|
|
fail!(~"read_map_elt_val is unimplemented");
|
|
}
|
|
|
|
fn read_map_elt_val<T>(&mut self,
|
|
idx: uint,
|
|
_: &fn(&mut Decoder) -> T)
|
|
-> T {
|
|
debug!("read_map_elt_val(idx=%u)", idx);
|
|
fail!(~"read_map_elt_val is unimplemented");
|
|
}
|
|
}
|
|
}
|
|
|
|
pub mod writer {
|
|
use ebml::{EbmlEncoderTag, EsBool, EsEnum, EsEnumBody, EsEnumVid};
|
|
use ebml::{EsI16, EsI32, EsI64, EsI8, EsInt};
|
|
use ebml::{EsLabel, EsOpaque, EsStr, EsU16, EsU32, EsU64, EsU8, EsUint};
|
|
use ebml::{EsVec, EsVecElt, EsVecLen};
|
|
|
|
use core::io;
|
|
use core::str;
|
|
use core::vec;
|
|
|
|
// ebml writing
|
|
pub struct Encoder {
|
|
writer: @io::Writer,
|
|
priv mut size_positions: ~[uint],
|
|
}
|
|
|
|
fn write_sized_vuint(w: @io::Writer, 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!(fmt!("vint to write too big: %?", n))
|
|
};
|
|
}
|
|
|
|
fn write_vuint(w: @io::Writer, 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!(fmt!("vint to write too big: %?", n));
|
|
}
|
|
|
|
pub fn Encoder(w: @io::Writer) -> Encoder {
|
|
let size_positions: ~[uint] = ~[];
|
|
Encoder { writer: w, mut size_positions: size_positions }
|
|
}
|
|
|
|
// FIXME (#2741): Provide a function to write the standard ebml header.
|
|
pub impl Encoder {
|
|
fn start_tag(&mut self, tag_id: uint) {
|
|
debug!("Start tag %u", tag_id);
|
|
|
|
// Write the enum ID:
|
|
write_vuint(self.writer, tag_id);
|
|
|
|
// Write a placeholder four-byte size.
|
|
self.size_positions.push(self.writer.tell());
|
|
let zeroes: &[u8] = &[0u8, 0u8, 0u8, 0u8];
|
|
self.writer.write(zeroes);
|
|
}
|
|
|
|
fn end_tag(&mut self) {
|
|
let last_size_pos = self.size_positions.pop();
|
|
let cur_pos = self.writer.tell();
|
|
self.writer.seek(last_size_pos as int, io::SeekSet);
|
|
let size = (cur_pos - last_size_pos - 4u);
|
|
write_sized_vuint(self.writer, size, 4u);
|
|
self.writer.seek(cur_pos as int, io::SeekSet);
|
|
|
|
debug!("End tag (size = %u)", size);
|
|
}
|
|
|
|
fn wr_tag(&mut self, tag_id: uint, blk: &fn()) {
|
|
self.start_tag(tag_id);
|
|
blk();
|
|
self.end_tag();
|
|
}
|
|
|
|
fn wr_tagged_bytes(&mut self, tag_id: uint, b: &[u8]) {
|
|
write_vuint(self.writer, tag_id);
|
|
write_vuint(self.writer, vec::len(b));
|
|
self.writer.write(b);
|
|
}
|
|
|
|
fn wr_tagged_u64(&mut self, tag_id: uint, v: u64) {
|
|
do io::u64_to_be_bytes(v, 8u) |v| {
|
|
self.wr_tagged_bytes(tag_id, v);
|
|
}
|
|
}
|
|
|
|
fn wr_tagged_u32(&mut self, tag_id: uint, v: u32) {
|
|
do io::u64_to_be_bytes(v as u64, 4u) |v| {
|
|
self.wr_tagged_bytes(tag_id, v);
|
|
}
|
|
}
|
|
|
|
fn wr_tagged_u16(&mut self, tag_id: uint, v: u16) {
|
|
do io::u64_to_be_bytes(v as u64, 2u) |v| {
|
|
self.wr_tagged_bytes(tag_id, v);
|
|
}
|
|
}
|
|
|
|
fn wr_tagged_u8(&mut self, tag_id: uint, v: u8) {
|
|
self.wr_tagged_bytes(tag_id, &[v]);
|
|
}
|
|
|
|
fn wr_tagged_i64(&mut self, tag_id: uint, v: i64) {
|
|
do io::u64_to_be_bytes(v as u64, 8u) |v| {
|
|
self.wr_tagged_bytes(tag_id, v);
|
|
}
|
|
}
|
|
|
|
fn wr_tagged_i32(&mut self, tag_id: uint, v: i32) {
|
|
do io::u64_to_be_bytes(v as u64, 4u) |v| {
|
|
self.wr_tagged_bytes(tag_id, v);
|
|
}
|
|
}
|
|
|
|
fn wr_tagged_i16(&mut self, tag_id: uint, v: i16) {
|
|
do io::u64_to_be_bytes(v as u64, 2u) |v| {
|
|
self.wr_tagged_bytes(tag_id, v);
|
|
}
|
|
}
|
|
|
|
fn wr_tagged_i8(&mut self, tag_id: uint, v: i8) {
|
|
self.wr_tagged_bytes(tag_id, &[v as u8]);
|
|
}
|
|
|
|
fn wr_tagged_str(&mut self, tag_id: uint, v: &str) {
|
|
str::byte_slice(v, |b| self.wr_tagged_bytes(tag_id, b));
|
|
}
|
|
|
|
fn wr_bytes(&mut self, b: &[u8]) {
|
|
debug!("Write %u bytes", vec::len(b));
|
|
self.writer.write(b);
|
|
}
|
|
|
|
fn wr_str(&mut self, s: &str) {
|
|
debug!("Write str: %?", s);
|
|
self.writer.write(str::to_bytes(s));
|
|
}
|
|
}
|
|
|
|
// 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;
|
|
|
|
priv impl Encoder {
|
|
// 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 impl Encoder {
|
|
fn emit_opaque(&mut self, f: &fn(&mut Encoder)) {
|
|
self.start_tag(EsOpaque as uint);
|
|
f(self);
|
|
self.end_tag();
|
|
}
|
|
}
|
|
|
|
impl ::serialize::Encoder for Encoder {
|
|
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)
|
|
}
|
|
|
|
// FIXME (#2742): implement these
|
|
fn emit_f64(&mut self, _v: f64) {
|
|
fail!(~"Unimplemented: serializing an f64");
|
|
}
|
|
fn emit_f32(&mut self, _v: f32) {
|
|
fail!(~"Unimplemented: serializing an f32");
|
|
}
|
|
fn emit_float(&mut self, _v: float) {
|
|
fail!(~"Unimplemented: serializing a float");
|
|
}
|
|
|
|
fn emit_char(&mut self, _v: char) {
|
|
fail!(~"Unimplemented: serializing a char");
|
|
}
|
|
|
|
fn emit_str(&mut self, v: &str) {
|
|
self.wr_tagged_str(EsStr as uint, v)
|
|
}
|
|
|
|
fn emit_enum(&mut self, name: &str, f: &fn(&mut Encoder)) {
|
|
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: &fn(&mut Encoder)) {
|
|
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: &fn(&mut Encoder)) {
|
|
f(self)
|
|
}
|
|
|
|
fn emit_enum_struct_variant(&mut self,
|
|
v_name: &str,
|
|
v_id: uint,
|
|
cnt: uint,
|
|
f: &fn(&mut Encoder)) {
|
|
self.emit_enum_variant(v_name, v_id, cnt, f)
|
|
}
|
|
|
|
fn emit_enum_struct_variant_field(&mut self,
|
|
_: &str,
|
|
idx: uint,
|
|
f: &fn(&mut Encoder)) {
|
|
self.emit_enum_variant_arg(idx, f)
|
|
}
|
|
|
|
fn emit_struct(&mut self, _: &str, _len: uint, f: &fn(&mut Encoder)) {
|
|
f(self)
|
|
}
|
|
|
|
fn emit_struct_field(&mut self,
|
|
name: &str,
|
|
_: uint,
|
|
f: &fn(&mut Encoder)) {
|
|
self._emit_label(name);
|
|
f(self)
|
|
}
|
|
|
|
fn emit_tuple(&mut self, len: uint, f: &fn(&mut Encoder)) {
|
|
self.emit_seq(len, f)
|
|
}
|
|
fn emit_tuple_arg(&mut self, idx: uint, f: &fn(&mut Encoder)) {
|
|
self.emit_seq_elt(idx, f)
|
|
}
|
|
|
|
fn emit_tuple_struct(&mut self,
|
|
_: &str,
|
|
len: uint,
|
|
f: &fn(&mut Encoder)) {
|
|
self.emit_seq(len, f)
|
|
}
|
|
fn emit_tuple_struct_arg(&mut self, idx: uint, f: &fn(&mut Encoder)) {
|
|
self.emit_seq_elt(idx, f)
|
|
}
|
|
|
|
fn emit_option(&mut self, f: &fn(&mut Encoder)) {
|
|
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: &fn(&mut Encoder)) {
|
|
self.emit_enum_variant("Some", 1, 1, f)
|
|
}
|
|
|
|
fn emit_seq(&mut self, len: uint, f: &fn(&mut Encoder)) {
|
|
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: &fn(&mut Encoder)) {
|
|
self.start_tag(EsVecElt as uint);
|
|
f(self);
|
|
self.end_tag();
|
|
}
|
|
|
|
fn emit_map(&mut self, _len: uint, _f: &fn(&mut Encoder)) {
|
|
fail!(~"emit_map is unimplemented");
|
|
}
|
|
|
|
fn emit_map_elt_key(&mut self, _idx: uint, _f: &fn(&mut Encoder)) {
|
|
fail!(~"emit_map_elt_key is unimplemented");
|
|
}
|
|
|
|
fn emit_map_elt_val(&mut self, _idx: uint, _f: &fn(&mut Encoder)) {
|
|
fail!(~"emit_map_elt_val is unimplemented");
|
|
}
|
|
}
|
|
}
|
|
|
|
// ___________________________________________________________________________
|
|
// Testing
|
|
|
|
#[cfg(test)]
|
|
mod tests {
|
|
use ebml::reader;
|
|
use ebml::writer;
|
|
use serialize::Encodable;
|
|
use serialize;
|
|
|
|
use core::io;
|
|
use core::option::{None, Option, Some};
|
|
|
|
#[test]
|
|
fn test_option_int() {
|
|
fn test_v(v: Option<int>) {
|
|
debug!("v == %?", v);
|
|
let bytes = do io::with_bytes_writer |wr| {
|
|
let mut ebml_w = writer::Encoder(wr);
|
|
v.encode(&mut ebml_w)
|
|
};
|
|
let ebml_doc = reader::Doc(@bytes);
|
|
let mut deser = reader::Decoder(ebml_doc);
|
|
let v1 = serialize::Decodable::decode(&mut deser);
|
|
debug!("v1 == %?", v1);
|
|
assert!(v == v1);
|
|
}
|
|
|
|
test_v(Some(22));
|
|
test_v(None);
|
|
test_v(Some(3));
|
|
}
|
|
}
|