Crate abx 

abx — Android Binary XML parser

Parses the ABX (Android Binary XML) format produced by BinaryXmlSerializer and read back by BinaryXmlPullParser in AOSP.

Not to be confused with AXML, the unrelated chunk-based binary format used for compiled resources inside APKs (AndroidManifest.xml, res/**/*.xml) — this crate does not read that format. See the crate README’s “Not AXML” section for the comparison.

Two parsers, one format

Parser	Input	When to use
AbxParser	&[u8]	Data already in memory
AbxStreamParser	impl Read	Files, sockets, pipes — any reader

Format overview

Every file starts with the 4-byte magic ABX\0 (0x41 0x42 0x58 0x00). After the magic each token is a single byte split into two nibbles:

high nibble (0xF0) → data-type  (TYPE_STRING, TYPE_INT, …)
low  nibble (0x0F) → event kind (START_TAG, ATTRIBUTE, …)

Interned strings are prefixed with a u16 index; the sentinel value 0xFFFF means “new string follows as a length-prefixed UTF-8 blob”.

Quick start

// Slice-based
use abx::AbxParser;
let data = std::fs::read("foo.abx")?;
let mut p = AbxParser::new(&data)?;
while let Some(ev) = p.next_event()? { println!("{ev:?}"); }

// Stream-based (no intermediate Vec)
use abx::AbxStreamParser;
let file = std::fs::File::open("foo.abx")?;
let mut p = AbxStreamParser::new(std::io::BufReader::new(file))?;
while let Some(ev) = p.next_event()? { println!("{ev:?}"); }

// Convenience helper
let mut p = abx::open_file("foo.abx")?;
let xml = p.to_xml()?;

Crate layout

error, wire, event, decode (in-memory + streaming parsers, see stream), and de (serde support, behind the serialize feature) are internal modules — everything is re-exported at the crate root, so abx::Event etc. work regardless of which file it’s defined in.

Modules

stream

AbxStreamParser — pull parser over any Read source.

Structs

AbxParser

Zero-allocation pull parser that works on an in-memory &[u8].

AbxParserOwned

Heap-owning wrapper. Stores the raw bytes and hands out AbxParser borrows without lifetime gymnastics on the call-site.

AbxStreamParser

Pull parser that reads from any R: Read source.

AbxWriter

Encodes Events to any W: Write sink. Vec<u8> covers the in-memory case (it implements Write); a file/socket/BufWriter covers streaming — unlike the decode side, writing has no ring-buffer/refill complexity to split across two types.

Attribute

One XML attribute: a name plus its typed value.

Enums

AbxError

Everything that can go wrong parsing, encoding, or deserializing ABX data.

AttributeValue

The typed payload of an XML attribute.

Event

One XmlPullParser-style parse event, as read from (or written to) an ABX stream.

Constants

MAGIC

Magic header bytes: ABX\0

Functions

abx_events

Parse ABX bytes and return all events.

abx_to_xml

Convert ABX bytes to an XML string.

events_to_abx

Encode a full Event stream to an in-memory ABX byte buffer.

from_element

Deserialize a single element’s attributes (and optional text content) into T, honoring #[serde(rename = "...")], Option<T> for absent attributes, and numeric/bytes coercions. This convenience entry point has no child elements to offer — it’s meant for callers who already have an Event::StartTag’s attributes in hand. Nested-child mapping is only available through crate::AbxParser::deserialize_next and crate::AbxStreamParser::deserialize_next, which build the child tree by walking the event stream.

from_file

Open a file and deserialize its root element into T.

from_reader

Streaming equivalent of from_slice: deserialize the root element of an ABX document read from any std::io::Read source.

from_slice

Deserialize an entire in-memory ABX document into T, using its root element. The one-shot entry point for “this whole document is one struct” — no parser to construct, no element name to spell out. Matches quick-xml’s from_str/serde_json’s from_slice: the root’s tag name is not checked against T at all, so name your types however you like.

open_file

Open a file and return a buffered AbxStreamParser over it.

xml_to_abx

Encode XML text to ABX bytes.

Type Aliases

InternedStr

A tag or attribute name read from the wire format’s interned-string pool. The same handful of names (pkg, name, version, …) repeat across every element in a typical document, so back-reference clones need to be cheap.

Result

This crate’s Result alias, with AbxError as the error type.