error.rs

//! Errors returned by OpenSSL library.
//!
//! OpenSSL errors are stored in an `ErrorStack`.  Most methods in the crate
/// returns a `Result<T, ErrorStack>` type.
//!
//! # Examples
//!
//! ```
//! use openssl::error::ErrorStack;
//! use openssl::bn::BigNum;
//!
//! let an_error = BigNum::from_dec_str("Cannot parse letters");
//! match an_error {
//!     Ok(_)  => _,
//!     Err(e) => println!("Parsing Error: {:?}", e),
//! }
//! ```
use libc::{c_ulong, c_char, c_int};
use std::fmt;
use std::error;
use std::ffi::CStr;
use std::io;
use std::str;
use std::ptr;
use std::borrow::Cow;

use ffi;

/// Collection of [`Error`]s from OpenSSL.
///
/// [`Error`]: struct.Error.html
#[derive(Debug, Clone)]
pub struct ErrorStack(Vec<Error>);

impl ErrorStack {
    /// Returns the contents of the OpenSSL error stack.
    pub fn get() -> ErrorStack {
        let mut vec = vec![];
        while let Some(err) = Error::get() {
            vec.push(err);
        }
        ErrorStack(vec)
    }
}

impl ErrorStack {
    /// Returns the errors in the stack.
    pub fn errors(&self) -> &[Error] {
        &self.0
    }
}

impl fmt::Display for ErrorStack {
    fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
        let mut first = true;
        for err in &self.0 {
            if !first {
                fmt.write_str(", ")?;
            }
            write!(fmt, "{}", err)?;
            first = false;
        }
        Ok(())
    }
}

impl error::Error for ErrorStack {
    fn description(&self) -> &str {
        "An OpenSSL error stack"
    }