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/*! This crate provides an implementation of the [Snappy compression format](https://github.com/google/snappy/blob/master/format_description.txt), as well as the [framing format](https://github.com/google/snappy/blob/master/framing_format.txt). The goal of Snappy is to provide reasonable compression at high speed. On a modern CPU, Snappy can compress data at about 300 MB/sec or more and can decompress data at about 800 MB/sec or more. # Install To use this crate with [Cargo](http://doc.crates.io/index.html), simply add it as a dependency to your `Cargo.toml`: ```ignore [dependencies] snap = "0.1" ``` and add `extern crate snap;` to your crate root. # Overview This crate provides two ways to use Snappy. The first way is through the `Reader` and `Writer` types, which implement the `std::io::Read` and `std::io::Write` traits with the Snappy frame format. Unless you have a specific reason to the contrary, you should only need to use these types. Specifically, the Snappy frame format permits streaming compression or decompression. The second way is through the `Decoder` and `Encoder` types. These types provide lower level control to the raw Snappy format, and don't support a streaming interface directly. You should only use these types if you know you specifically need the Snappy raw format. Finally, the `Error` type in this crate provides an exhaustive list of error conditions that are probably useless in most circumstances. Therefore, `From<snap::Error> for io::Error` is implemented in this crate, which will let you automatically convert a Snappy error to an `std::io::Error` (when using `try!`) with an appropriate error message to display to an end user. # Example: compress data on `stdin` This program reads data from `stdin`, compresses it and emits it to `stdout`. This example can be found in `examples/compress.rs`: ```rust,ignore extern crate snap; use std::io; fn main() { let stdin = io::stdin(); let stdout = io::stdout(); let mut rdr = stdin.lock(); // Wrap the stdout writer in a Snappy writer. let mut wtr = snap::Writer::new(stdout.lock()); io::copy(&mut rdr, &mut wtr).expect("I/O operation failed"); } ``` # Example: decompress data on `stdin` This program reads data from `stdin`, decompresses it and emits it to `stdout`. This example can be found in `examples/decompress.rs`: ```rust,ignore extern crate snap; use std::io; fn main() { let stdin = io::stdin(); let stdout = io::stdout(); // Wrap the stdin reader in a Snappy reader. let mut rdr = snap::Reader::new(stdin.lock()); let mut wtr = stdout.lock(); io::copy(&mut rdr, &mut wtr).expect("I/O operation failed"); } ``` */ #![deny(missing_docs)] extern crate byteorder; #[macro_use] extern crate lazy_static; #[cfg(test)] extern crate quickcheck; #[cfg(test)] extern crate rand; #[cfg(all(test, feature = "cpp"))] extern crate snappy_cpp; pub use compress::{Encoder, max_compress_len}; pub use decompress::{Decoder, decompress_len}; pub use error::{Error, IntoInnerError, Result}; pub use frame::{Reader, Writer}; /// We don't permit compressing a block bigger than what can fit in a u32. const MAX_INPUT_SIZE: u64 = ::std::u32::MAX as u64; /// The maximum number of bytes that we process at once. A block is the unit /// at which we scan for candidates for compression. const MAX_BLOCK_SIZE: usize = 1<<16; mod compress; mod crc32; mod decompress; mod error; mod frame; mod tag; #[cfg(test)] mod tests; mod varint;