sstable 0.11.1

Sorted String Tables, an on-disk format for storing immutable maps consisting of string,string pairs, and retrieving values by key efficiently. This crate also features bloom filters, checksums and skipping bad blocks. It is based on the code implemented for the rusty_leveldb crate.
Documentation 
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use std::convert::From;
use std::error::Error;
use std::fmt::{self, Display, Formatter};
use std::io;
use std::result;
use std::sync;

use snap;

/// StatusCode describes various failure modes of database operations.
#[derive(Clone, Debug, PartialEq)]
#[allow(dead_code)]
pub enum StatusCode {
    OK,

    AlreadyExists,
    Corruption,
    CompressionError,
    IOError,
    InvalidArgument,
    InvalidData,
    LockError,
    NotFound,
    NotSupported,
    PermissionDenied,
    Unknown,
}

/// Status encapsulates a `StatusCode` and an error message. It can be displayed, and also
/// implements `Error`. io::Error can be converted into Status.
#[derive(Clone, Debug, PartialEq)]
pub struct Status {
    pub code: StatusCode,
    pub err: String,
}

impl Default for Status {
    fn default() -> Status {
        Status {
            code: StatusCode::OK,
            err: String::new(),
        }
    }
}

impl Display for Status {
    fn fmt(&self, fmt: &mut Formatter) -> result::Result<(), fmt::Error> {
        fmt.write_str(&self.to_string())
    }
}

impl Error for Status {
    fn description(&self) -> &str {
        &self.err
    }
}

impl Status {
    pub fn new(code: StatusCode, msg: &str) -> Status {
        let err;
        if msg.is_empty() {
            err = format!("{:?}", code)
        } else {
            err = format!("{:?}: {}", code, msg);
        }
        return Status {
            code: code,
            err: err,
        };
    }
}

impl From<io::Error> for Status {
    fn from(e: io::Error) -> Status {
        let c = match e.kind() {
            io::ErrorKind::NotFound => StatusCode::NotFound,
            io::ErrorKind::InvalidData => StatusCode::Corruption,
            io::ErrorKind::InvalidInput => StatusCode::InvalidArgument,
            io::ErrorKind::PermissionDenied => StatusCode::PermissionDenied,
            _ => StatusCode::IOError,
        };

        Status::new(c, &e.to_string())
    }
}

impl<T> From<sync::PoisonError<T>> for Status {
    fn from(_: sync::PoisonError<T>) -> Status {
        Status::new(StatusCode::LockError, "lock poisoned")
    }
}

impl From<snap::Error> for Status {
    fn from(e: snap::Error) -> Status {
        Status {
            code: StatusCode::CompressionError,
            err: e.to_string(),
        }
    }
}

/// The sstable result type.
pub type Result<T> = result::Result<T, Status>;

/// err returns a new Status wrapped in a Result.
pub fn err<T>(code: StatusCode, msg: &str) -> Result<T> {
    Err(Status::new(code, msg))
}