rust/src/libstd/io.rs
2013-07-23 16:56:22 -07:00

2121 lines
52 KiB
Rust

// Copyright 2012 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
/*!
The `io` module contains basic input and output routines.
A quick summary:
## `Reader` and `Writer` traits
These traits define the minimal set of methods that anything that can do
input and output should implement.
## `ReaderUtil` and `WriterUtil` traits
Richer methods that allow you to do more. `Reader` only lets you read a certain
number of bytes into a buffer, while `ReaderUtil` allows you to read a whole
line, for example.
Generally, these richer methods are probably the ones you want to actually
use in day-to-day Rust.
Furthermore, because there is an implementation of `ReaderUtil` for
`<T: Reader>`, when your input or output code implements `Reader`, you get
all of these methods for free.
## `print` and `println`
These very useful functions are defined here. You generally don't need to
import them, though, as the prelude already does.
## `stdin`, `stdout`, and `stderr`
These functions return references to the classic three file descriptors. They
implement `Reader` and `Writer`, where appropriate.
*/
#[allow(missing_doc)];
use result::Result;
use clone::Clone;
use container::Container;
use int;
use libc;
use libc::{c_int, c_long, c_void, size_t, ssize_t};
use libc::consts::os::posix88::*;
use num;
use os;
use cast;
use path::Path;
use ops::Drop;
use iterator::IteratorUtil;
use ptr;
use result;
use str;
use str::{StrSlice, OwnedStr};
use to_str::ToStr;
use uint;
use vec;
use vec::{MutableVector, ImmutableVector, OwnedVector, OwnedCopyableVector, CopyableVector};
#[allow(non_camel_case_types)] // not sure what to do about this
pub type fd_t = c_int;
pub mod rustrt {
use libc;
#[abi = "cdecl"]
#[link_name = "rustrt"]
extern {
pub unsafe fn rust_get_stdin() -> *libc::FILE;
pub unsafe fn rust_get_stdout() -> *libc::FILE;
pub unsafe fn rust_get_stderr() -> *libc::FILE;
}
}
// Reading
// FIXME (#2004): This is all buffered. We might need an unbuffered variant
// as well
/**
* The SeekStyle enum describes the relationship between the position
* we'd like to seek to from our current position. It's used as an argument
* to the `seek` method defined on the `Reader` trait.
*
* There are three seek styles:
*
* 1. `SeekSet` means that the new position should become our position.
* 2. `SeekCur` means that we should seek from the current position.
* 3. `SeekEnd` means that we should seek from the end.
*
* # Examples
*
* None right now.
*/
pub enum SeekStyle { SeekSet, SeekEnd, SeekCur, }
/**
* The core Reader trait. All readers must implement this trait.
*
* # Examples
*
* None right now.
*/
pub trait Reader {
// FIXME (#2004): Seekable really should be orthogonal.
// FIXME (#2982): This should probably return an error.
/**
* Reads bytes and puts them into `bytes`, advancing the cursor. Returns the
* number of bytes read.
*
* The number of bytes to be read is `len` or the end of the file,
* whichever comes first.
*
* The buffer must be at least `len` bytes long.
*
* `read` is conceptually similar to C's `fread` function.
*
* # Examples
*
* None right now.
*/
fn read(&self, bytes: &mut [u8], len: uint) -> uint;
/**
* Reads a single byte, advancing the cursor.
*
* In the case of an EOF or an error, returns a negative value.
*
* `read_byte` is conceptually similar to C's `getc` function.
*
* # Examples
*
* None right now.
*/
fn read_byte(&self) -> int;
/**
* Returns a boolean value: are we currently at EOF?
*
* `eof` is conceptually similar to C's `feof` function.
*
* # Examples
*
* None right now.
*/
fn eof(&self) -> bool;
/**
* Seek to a given `position` in the stream.
*
* Takes an optional SeekStyle, which affects how we seek from the
* position. See `SeekStyle` docs for more details.
*
* `seek` is conceptually similar to C's `fseek` function.
*
* # Examples
*
* None right now.
*/
fn seek(&self, position: int, style: SeekStyle);
/**
* Returns the current position within the stream.
*
* `tell` is conceptually similar to C's `ftell` function.
*
* # Examples
*
* None right now.
*/
fn tell(&self) -> uint;
}
impl Reader for @Reader {
fn read(&self, bytes: &mut [u8], len: uint) -> uint {
self.read(bytes, len)
}
fn read_byte(&self) -> int {
self.read_byte()
}
fn eof(&self) -> bool {
self.eof()
}
fn seek(&self, position: int, style: SeekStyle) {
self.seek(position, style)
}
fn tell(&self) -> uint {
self.tell()
}
}
/**
* The `ReaderUtil` trait is a home for many of the utility functions
* a particular Reader should implement.
*
* The default `Reader` trait is focused entirely on bytes. `ReaderUtil` is based
* on higher-level concepts like 'chars' and 'lines.'
*
* # Examples:
*
* None right now.
*/
pub trait ReaderUtil {
/**
* Reads `len` number of bytes, and gives you a new vector back.
*
* # Examples
*
* None right now.
*/
fn read_bytes(&self, len: uint) -> ~[u8];
/**
* Reads up until a specific byte is seen or EOF.
*
* The `include` parameter specifies if the character should be included
* in the returned string.
*
* # Examples
*
* None right now.
*/
fn read_until(&self, c: u8, include: bool) -> ~str;
/**
* Reads up until the first '\n' or EOF.
*
* The '\n' is not included in the result.
*
* # Examples
*
* None right now.
*/
fn read_line(&self) -> ~str;
/**
* Reads `n` chars.
*
* Assumes that those chars are UTF-8 encoded.
*
* The '\n' is not included in the result.
*
* # Examples
*
* None right now.
*/
fn read_chars(&self, n: uint) -> ~[char];
/**
* Reads a single UTF-8 encoded char.
*
* # Examples
*
* None right now.
*/
fn read_char(&self) -> char;
/**
* Reads up until the first null byte or EOF.
*
* The null byte is not returned.
*
* # Examples
*
* None right now.
*/
fn read_c_str(&self) -> ~str;
/**
* Reads all remaining data in the stream.
*
* # Examples
*
* None right now.
*/
fn read_whole_stream(&self) -> ~[u8];
/**
* Iterate over every byte until EOF or the iterator breaks.
*
* # Examples
*
* None right now.
*/
fn each_byte(&self, it: &fn(int) -> bool) -> bool;
/**
* Iterate over every char until EOF or the iterator breaks.
*
* # Examples
*
* None right now.
*/
fn each_char(&self, it: &fn(char) -> bool) -> bool;
/**
* Iterate over every line until EOF or the iterator breaks.
*
* # Examples
*
* None right now.
*/
fn each_line(&self, it: &fn(&str) -> bool) -> bool;
/**
* Reads all of the lines in the stream.
*
* Returns a vector of those lines.
*
* # Examples
*
* None right now.
*/
fn read_lines(&self) -> ~[~str];
/**
* Reads `n` little-endian unsigned integer bytes.
*
* `n` must be between 1 and 8, inclusive.
*
* # Examples
*
* None right now.
*/
fn read_le_uint_n(&self, nbytes: uint) -> u64;
/**
* Reads `n` little-endian signed integer bytes.
*
* `n` must be between 1 and 8, inclusive.
*
* # Examples
*
* None right now.
*/
fn read_le_int_n(&self, nbytes: uint) -> i64;
/**
* Reads `n` big-endian unsigned integer bytes.
*
* `n` must be between 1 and 8, inclusive.
*
* # Examples
*
* None right now.
*/
fn read_be_uint_n(&self, nbytes: uint) -> u64;
/**
* Reads `n` big-endian signed integer bytes.
*
* `n` must be between 1 and 8, inclusive.
*
* # Examples
*
* None right now.
*/
fn read_be_int_n(&self, nbytes: uint) -> i64;
/**
* Reads a little-endian unsigned integer.
*
* The number of bytes returned is system-dependant.
*
* # Examples
*
* None right now.
*/
fn read_le_uint(&self) -> uint;
/**
* Reads a little-endian integer.
*
* The number of bytes returned is system-dependant.
*
* # Examples
*
* None right now.
*/
fn read_le_int(&self) -> int;
/**
* Reads a big-endian unsigned integer.
*
* The number of bytes returned is system-dependant.
*
* # Examples
*
* None right now.
*/
fn read_be_uint(&self) -> uint;
/**
* Reads a big-endian integer.
*
* The number of bytes returned is system-dependant.
*
* # Examples
*
* None right now.
*/
fn read_be_int(&self) -> int;
/**
* Reads a big-endian `u64`.
*
* `u64`s are 8 bytes long.
*
* # Examples
*
* None right now.
*/
fn read_be_u64(&self) -> u64;
/**
* Reads a big-endian `u32`.
*
* `u32`s are 4 bytes long.
*
* # Examples
*
* None right now.
*/
fn read_be_u32(&self) -> u32;
/**
* Reads a big-endian `u16`.
*
* `u16`s are 2 bytes long.
*
* # Examples
*
* None right now.
*/
fn read_be_u16(&self) -> u16;
/**
* Reads a big-endian `i64`.
*
* `i64`s are 8 bytes long.
*
* # Examples
*
* None right now.
*/
fn read_be_i64(&self) -> i64;
/**
* Reads a big-endian `i32`.
*
* `i32`s are 4 bytes long.
*
* # Examples
*
* None right now.
*/
fn read_be_i32(&self) -> i32;
/**
* Reads a big-endian `i16`.
*
* `i16`s are 2 bytes long.
*
* # Examples
*
* None right now.
*/
fn read_be_i16(&self) -> i16;
/**
* Reads a big-endian `f64`.
*
* `f64`s are 8 byte, IEEE754 double-precision floating point numbers.
*
* # Examples
*
* None right now.
*/
fn read_be_f64(&self) -> f64;
/**
* Reads a big-endian `f32`.
*
* `f32`s are 4 byte, IEEE754 single-precision floating point numbers.
*
* # Examples
*
* None right now.
*/
fn read_be_f32(&self) -> f32;
/**
* Reads a little-endian `u64`.
*
* `u64`s are 8 bytes long.
*
* # Examples
*
* None right now.
*/
fn read_le_u64(&self) -> u64;
/**
* Reads a little-endian `u32`.
*
* `u32`s are 4 bytes long.
*
* # Examples
*
* None right now.
*/
fn read_le_u32(&self) -> u32;
/**
* Reads a little-endian `u16`.
*
* `u16`s are 2 bytes long.
*
* # Examples
*
* None right now.
*/
fn read_le_u16(&self) -> u16;
/**
* Reads a little-endian `i64`.
*
* `i64`s are 8 bytes long.
*
* # Examples
*
* None right now.
*/
fn read_le_i64(&self) -> i64;
/**
* Reads a little-endian `i32`.
*
* `i32`s are 4 bytes long.
*
* # Examples
*
* None right now.
*/
fn read_le_i32(&self) -> i32;
/**
* Reads a little-endian `i16`.
*
* `i16`s are 2 bytes long.
*
* # Examples
*
* None right now.
*/
fn read_le_i16(&self) -> i16;
/**
* Reads a little-endian `f64`.
*
* `f64`s are 8 byte, IEEE754 double-precision floating point numbers.
*
* # Examples
*
* None right now.
*/
fn read_le_f64(&self) -> f64;
/**
* Reads a little-endian `f32`.
*
* `f32`s are 4 byte, IEEE754 single-precision floating point numbers.
*
* # Examples
*
* None right now.
*/
fn read_le_f32(&self) -> f32;
/**
* Read a u8.
*
* `u8`s are 1 byte.
*
* # Examples
*
* None right now.
*/
fn read_u8(&self) -> u8;
/**
* Read an i8.
*
* `i8`s are 1 byte.
*
* # Examples
*
* None right now.
*/
fn read_i8(&self) -> i8;
}
impl<T:Reader> ReaderUtil for T {
fn read_bytes(&self,len: uint) -> ~[u8] {
let mut bytes = vec::with_capacity(len);
unsafe { vec::raw::set_len(&mut bytes, len); }
let count = self.read(bytes, len);
unsafe { vec::raw::set_len(&mut bytes, count); }
bytes
}
fn read_until(&self, c: u8, include: bool) -> ~str {
let mut bytes = ~[];
loop {
let ch = self.read_byte();
if ch == -1 || ch == c as int {
if include && ch == c as int {
bytes.push(ch as u8);
}
break;
}
bytes.push(ch as u8);
}
str::from_bytes(bytes)
}
fn read_line(&self) -> ~str {
self.read_until('\n' as u8, false)
}
fn read_chars(&self, n: uint) -> ~[char] {
// returns the (consumed offset, n_req), appends characters to &chars
fn chars_from_bytes<T:Reader>(bytes: &~[u8], chars: &mut ~[char])
-> (uint, uint) {
let mut i = 0;
let bytes_len = bytes.len();
while i < bytes_len {
let b0 = bytes[i];
let w = str::utf8_char_width(b0);
let end = i + w;
i += 1;
assert!((w > 0));
if w == 1 {
chars.push(b0 as char);
loop;
}
// can't satisfy this char with the existing data
if end > bytes_len {
return (i - 1, end - bytes_len);
}
let mut val = 0;
while i < end {
let next = bytes[i] as int;
i += 1;
assert!((next > -1));
assert_eq!(next & 192, 128);
val <<= 6;
val += (next & 63) as uint;
}
// See str::StrSlice::char_at
val += ((b0 << ((w + 1) as u8)) as uint)
<< (w - 1) * 6 - w - 1u;
chars.push(val as char);
}
return (i, 0);
}
let mut bytes = ~[];
let mut chars = ~[];
// might need more bytes, but reading n will never over-read
let mut nbread = n;
while nbread > 0 {
let data = self.read_bytes(nbread);
if data.is_empty() {
// eof - FIXME (#2004): should we do something if
// we're split in a unicode char?
break;
}
bytes.push_all(data);
let (offset, nbreq) = chars_from_bytes::<T>(&bytes, &mut chars);
let ncreq = n - chars.len();
// again we either know we need a certain number of bytes
// to complete a character, or we make sure we don't
// over-read by reading 1-byte per char needed
nbread = if ncreq > nbreq { ncreq } else { nbreq };
if nbread > 0 {
bytes = bytes.slice(offset, bytes.len()).to_owned();
}
}
chars
}
fn read_char(&self) -> char {
let c = self.read_chars(1);
if c.len() == 0 {
return -1 as char; // FIXME will this stay valid? // #2004
}
assert_eq!(c.len(), 1);
return c[0];
}
fn read_c_str(&self) -> ~str {
self.read_until(0u8, false)
}
fn read_whole_stream(&self) -> ~[u8] {
let mut bytes: ~[u8] = ~[];
while !self.eof() { bytes.push_all(self.read_bytes(2048u)); }
bytes
}
fn each_byte(&self, it: &fn(int) -> bool) -> bool {
while !self.eof() {
if !it(self.read_byte()) { return false; }
}
return true;
}
fn each_char(&self, it: &fn(char) -> bool) -> bool {
while !self.eof() {
if !it(self.read_char()) { return false; }
}
return true;
}
fn each_line(&self, it: &fn(s: &str) -> bool) -> bool {
while !self.eof() {
// include the \n, so that we can distinguish an entirely empty
// line read after "...\n", and the trailing empty line in
// "...\n\n".
let mut line = self.read_until('\n' as u8, true);
// blank line at the end of the reader is ignored
if self.eof() && line.is_empty() { break; }
// trim the \n, so that each_line is consistent with read_line
let n = line.len();
if line[n-1] == '\n' as u8 {
unsafe { str::raw::set_len(&mut line, n-1); }
}
if !it(line) { return false; }
}
return true;
}
fn read_lines(&self) -> ~[~str] {
do vec::build |push| {
for self.each_line |line| {
push(str::to_owned(line));
}
}
}
// FIXME int reading methods need to deal with eof - issue #2004
fn read_le_uint_n(&self, nbytes: uint) -> u64 {
assert!(nbytes > 0 && nbytes <= 8);
let mut val = 0u64;
let mut pos = 0;
let mut i = nbytes;
while i > 0 {
val += (self.read_u8() as u64) << pos;
pos += 8;
i -= 1;
}
val
}
fn read_le_int_n(&self, nbytes: uint) -> i64 {
extend_sign(self.read_le_uint_n(nbytes), nbytes)
}
fn read_be_uint_n(&self, nbytes: uint) -> u64 {
assert!(nbytes > 0 && nbytes <= 8);
let mut val = 0u64;
let mut i = nbytes;
while i > 0 {
i -= 1;
val += (self.read_u8() as u64) << i * 8;
}
val
}
fn read_be_int_n(&self, nbytes: uint) -> i64 {
extend_sign(self.read_be_uint_n(nbytes), nbytes)
}
fn read_le_uint(&self) -> uint {
self.read_le_uint_n(uint::bytes) as uint
}
fn read_le_int(&self) -> int {
self.read_le_int_n(int::bytes) as int
}
fn read_be_uint(&self) -> uint {
self.read_be_uint_n(uint::bytes) as uint
}
fn read_be_int(&self) -> int {
self.read_be_int_n(int::bytes) as int
}
fn read_be_u64(&self) -> u64 {
self.read_be_uint_n(8) as u64
}
fn read_be_u32(&self) -> u32 {
self.read_be_uint_n(4) as u32
}
fn read_be_u16(&self) -> u16 {
self.read_be_uint_n(2) as u16
}
fn read_be_i64(&self) -> i64 {
self.read_be_int_n(8) as i64
}
fn read_be_i32(&self) -> i32 {
self.read_be_int_n(4) as i32
}
fn read_be_i16(&self) -> i16 {
self.read_be_int_n(2) as i16
}
fn read_be_f64(&self) -> f64 {
unsafe {
cast::transmute::<u64, f64>(self.read_be_u64())
}
}
fn read_be_f32(&self) -> f32 {
unsafe {
cast::transmute::<u32, f32>(self.read_be_u32())
}
}
fn read_le_u64(&self) -> u64 {
self.read_le_uint_n(8) as u64
}
fn read_le_u32(&self) -> u32 {
self.read_le_uint_n(4) as u32
}
fn read_le_u16(&self) -> u16 {
self.read_le_uint_n(2) as u16
}
fn read_le_i64(&self) -> i64 {
self.read_le_int_n(8) as i64
}
fn read_le_i32(&self) -> i32 {
self.read_le_int_n(4) as i32
}
fn read_le_i16(&self) -> i16 {
self.read_le_int_n(2) as i16
}
fn read_le_f64(&self) -> f64 {
unsafe {
cast::transmute::<u64, f64>(self.read_le_u64())
}
}
fn read_le_f32(&self) -> f32 {
unsafe {
cast::transmute::<u32, f32>(self.read_le_u32())
}
}
fn read_u8(&self) -> u8 {
self.read_byte() as u8
}
fn read_i8(&self) -> i8 {
self.read_byte() as i8
}
}
fn extend_sign(val: u64, nbytes: uint) -> i64 {
let shift = (8 - nbytes) * 8;
(val << shift) as i64 >> shift
}
// Reader implementations
fn convert_whence(whence: SeekStyle) -> i32 {
return match whence {
SeekSet => 0i32,
SeekCur => 1i32,
SeekEnd => 2i32
};
}
impl Reader for *libc::FILE {
fn read(&self, bytes: &mut [u8], len: uint) -> uint {
unsafe {
do bytes.as_mut_buf |buf_p, buf_len| {
assert!(buf_len >= len);
let count = libc::fread(buf_p as *mut c_void, 1u as size_t,
len as size_t, *self) as uint;
if count < len {
match libc::ferror(*self) {
0 => (),
_ => {
error!("error reading buffer");
error!("%s", os::last_os_error());
fail!();
}
}
}
count
}
}
}
fn read_byte(&self) -> int {
unsafe {
libc::fgetc(*self) as int
}
}
fn eof(&self) -> bool {
unsafe {
return libc::feof(*self) != 0 as c_int;
}
}
fn seek(&self, offset: int, whence: SeekStyle) {
unsafe {
assert!(libc::fseek(*self,
offset as c_long,
convert_whence(whence)) == 0 as c_int);
}
}
fn tell(&self) -> uint {
unsafe {
return libc::ftell(*self) as uint;
}
}
}
struct Wrapper<T, C> {
base: T,
cleanup: C,
}
// A forwarding impl of reader that also holds on to a resource for the
// duration of its lifetime.
// FIXME there really should be a better way to do this // #2004
impl<R:Reader,C> Reader for Wrapper<R, C> {
fn read(&self, bytes: &mut [u8], len: uint) -> uint {
self.base.read(bytes, len)
}
fn read_byte(&self) -> int { self.base.read_byte() }
fn eof(&self) -> bool { self.base.eof() }
fn seek(&self, off: int, whence: SeekStyle) {
self.base.seek(off, whence)
}
fn tell(&self) -> uint { self.base.tell() }
}
pub struct FILERes {
f: *libc::FILE,
}
impl FILERes {
pub fn new(f: *libc::FILE) -> FILERes {
FILERes { f: f }
}
}
impl Drop for FILERes {
fn drop(&self) {
unsafe {
libc::fclose(self.f);
}
}
}
pub fn FILE_reader(f: *libc::FILE, cleanup: bool) -> @Reader {
if cleanup {
@Wrapper { base: f, cleanup: FILERes::new(f) } as @Reader
} else {
@f as @Reader
}
}
// FIXME (#2004): this should either be an trait-less impl, a set of
// top-level functions that take a reader, or a set of default methods on
// reader (which can then be called reader)
/**
* Gives a `Reader` that allows you to read values from standard input.
*
* # Example
*
* ~~~ {.rust}
* let stdin = core::io::stdin();
* let line = stdin.read_line();
* core::io::print(line);
* ~~~
*/
pub fn stdin() -> @Reader {
unsafe {
@rustrt::rust_get_stdin() as @Reader
}
}
pub fn file_reader(path: &Path) -> Result<@Reader, ~str> {
let f = do path.to_str().as_c_str |pathbuf| {
do "r".as_c_str |modebuf| {
unsafe { libc::fopen(pathbuf, modebuf as *libc::c_char) }
}
};
if f as uint == 0u {
result::Err(~"error opening " + path.to_str())
} else {
result::Ok(FILE_reader(f, true))
}
}
// Byte readers
pub struct BytesReader {
// FIXME(#5723) see other FIXME below
// FIXME(#7268) this should also be parameterized over <'self>
bytes: &'static [u8],
pos: @mut uint
}
impl Reader for BytesReader {
fn read(&self, bytes: &mut [u8], len: uint) -> uint {
let count = num::min(len, self.bytes.len() - *self.pos);
let view = self.bytes.slice(*self.pos, self.bytes.len());
vec::bytes::copy_memory(bytes, view, count);
*self.pos += count;
count
}
fn read_byte(&self) -> int {
if *self.pos == self.bytes.len() {
return -1;
}
let b = self.bytes[*self.pos];
*self.pos += 1u;
b as int
}
fn eof(&self) -> bool {
*self.pos == self.bytes.len()
}
fn seek(&self, offset: int, whence: SeekStyle) {
let pos = *self.pos;
*self.pos = seek_in_buf(offset, pos, self.bytes.len(), whence);
}
fn tell(&self) -> uint {
*self.pos
}
}
pub fn with_bytes_reader<T>(bytes: &[u8], f: &fn(@Reader) -> T) -> T {
// XXX XXX XXX this is glaringly unsound
// FIXME(#5723) Use a &Reader for the callback's argument. Should be:
// fn with_bytes_reader<'r, T>(bytes: &'r [u8], f: &fn(&'r Reader) -> T) -> T
let bytes: &'static [u8] = unsafe { cast::transmute(bytes) };
f(@BytesReader {
bytes: bytes,
pos: @mut 0
} as @Reader)
}
pub fn with_str_reader<T>(s: &str, f: &fn(@Reader) -> T) -> T {
// FIXME(#5723): As above.
with_bytes_reader(s.as_bytes(), f)
}
// Writing
pub enum FileFlag { Append, Create, Truncate, NoFlag, }
// What type of writer are we?
#[deriving(Eq)]
pub enum WriterType { Screen, File }
// FIXME (#2004): Seekable really should be orthogonal.
// FIXME (#2004): eventually u64
/// The raw underlying writer trait. All writers must implement this.
pub trait Writer {
/// Write all of the given bytes.
fn write(&self, v: &[u8]);
/// Move the current position within the stream. The second parameter
/// determines the position that the first parameter is relative to.
fn seek(&self, int, SeekStyle);
/// Return the current position within the stream.
fn tell(&self) -> uint;
/// Flush the output buffer for this stream (if there is one).
fn flush(&self) -> int;
/// Determine if this Writer is writing to a file or not.
fn get_type(&self) -> WriterType;
}
impl Writer for @Writer {
fn write(&self, v: &[u8]) { self.write(v) }
fn seek(&self, a: int, b: SeekStyle) { self.seek(a, b) }
fn tell(&self) -> uint { self.tell() }
fn flush(&self) -> int { self.flush() }
fn get_type(&self) -> WriterType { self.get_type() }
}
impl<W:Writer,C> Writer for Wrapper<W, C> {
fn write(&self, bs: &[u8]) { self.base.write(bs); }
fn seek(&self, off: int, style: SeekStyle) { self.base.seek(off, style); }
fn tell(&self) -> uint { self.base.tell() }
fn flush(&self) -> int { self.base.flush() }
fn get_type(&self) -> WriterType { File }
}
impl Writer for *libc::FILE {
fn write(&self, v: &[u8]) {
unsafe {
do v.as_imm_buf |vbuf, len| {
let nout = libc::fwrite(vbuf as *c_void,
1,
len as size_t,
*self);
if nout != len as size_t {
error!("error writing buffer");
error!("%s", os::last_os_error());
fail!();
}
}
}
}
fn seek(&self, offset: int, whence: SeekStyle) {
unsafe {
assert!(libc::fseek(*self,
offset as c_long,
convert_whence(whence)) == 0 as c_int);
}
}
fn tell(&self) -> uint {
unsafe {
libc::ftell(*self) as uint
}
}
fn flush(&self) -> int {
unsafe {
libc::fflush(*self) as int
}
}
fn get_type(&self) -> WriterType {
unsafe {
let fd = libc::fileno(*self);
if libc::isatty(fd) == 0 { File }
else { Screen }
}
}
}
pub fn FILE_writer(f: *libc::FILE, cleanup: bool) -> @Writer {
if cleanup {
@Wrapper { base: f, cleanup: FILERes::new(f) } as @Writer
} else {
@f as @Writer
}
}
impl Writer for fd_t {
fn write(&self, v: &[u8]) {
unsafe {
let mut count = 0u;
do v.as_imm_buf |vbuf, len| {
while count < len {
let vb = ptr::offset(vbuf, count) as *c_void;
let nout = libc::write(*self, vb, len as size_t);
if nout < 0 as ssize_t {
error!("error writing buffer");
error!("%s", os::last_os_error());
fail!();
}
count += nout as uint;
}
}
}
}
fn seek(&self, _offset: int, _whence: SeekStyle) {
error!("need 64-bit foreign calls for seek, sorry");
fail!();
}
fn tell(&self) -> uint {
error!("need 64-bit foreign calls for tell, sorry");
fail!();
}
fn flush(&self) -> int { 0 }
fn get_type(&self) -> WriterType {
unsafe {
if libc::isatty(*self) == 0 { File } else { Screen }
}
}
}
pub struct FdRes {
fd: fd_t,
}
impl FdRes {
pub fn new(fd: fd_t) -> FdRes {
FdRes { fd: fd }
}
}
impl Drop for FdRes {
fn drop(&self) {
unsafe {
libc::close(self.fd);
}
}
}
pub fn fd_writer(fd: fd_t, cleanup: bool) -> @Writer {
if cleanup {
@Wrapper { base: fd, cleanup: FdRes::new(fd) } as @Writer
} else {
@fd as @Writer
}
}
pub fn mk_file_writer(path: &Path, flags: &[FileFlag])
-> Result<@Writer, ~str> {
#[cfg(windows)]
fn wb() -> c_int {
(O_WRONLY | libc::consts::os::extra::O_BINARY) as c_int
}
#[cfg(unix)]
fn wb() -> c_int { O_WRONLY as c_int }
let mut fflags: c_int = wb();
for flags.iter().advance |f| {
match *f {
Append => fflags |= O_APPEND as c_int,
Create => fflags |= O_CREAT as c_int,
Truncate => fflags |= O_TRUNC as c_int,
NoFlag => ()
}
}
let fd = unsafe {
do path.to_str().as_c_str |pathbuf| {
libc::open(pathbuf, fflags,
(S_IRUSR | S_IWUSR) as c_int)
}
};
if fd < (0 as c_int) {
result::Err(fmt!("error opening %s: %s", path.to_str(),
os::last_os_error()))
} else {
result::Ok(fd_writer(fd, true))
}
}
pub fn u64_to_le_bytes<T>(n: u64, size: uint,
f: &fn(v: &[u8]) -> T) -> T {
assert!(size <= 8u);
match size {
1u => f(&[n as u8]),
2u => f(&[n as u8,
(n >> 8) as u8]),
4u => f(&[n as u8,
(n >> 8) as u8,
(n >> 16) as u8,
(n >> 24) as u8]),
8u => f(&[n as u8,
(n >> 8) as u8,
(n >> 16) as u8,
(n >> 24) as u8,
(n >> 32) as u8,
(n >> 40) as u8,
(n >> 48) as u8,
(n >> 56) as u8]),
_ => {
let mut bytes: ~[u8] = ~[];
let mut i = size;
let mut n = n;
while i > 0u {
bytes.push((n & 255_u64) as u8);
n >>= 8_u64;
i -= 1u;
}
f(bytes)
}
}
}
pub fn u64_to_be_bytes<T>(n: u64, size: uint,
f: &fn(v: &[u8]) -> T) -> T {
assert!(size <= 8u);
match size {
1u => f(&[n as u8]),
2u => f(&[(n >> 8) as u8,
n as u8]),
4u => f(&[(n >> 24) as u8,
(n >> 16) as u8,
(n >> 8) as u8,
n as u8]),
8u => f(&[(n >> 56) as u8,
(n >> 48) as u8,
(n >> 40) as u8,
(n >> 32) as u8,
(n >> 24) as u8,
(n >> 16) as u8,
(n >> 8) as u8,
n as u8]),
_ => {
let mut bytes: ~[u8] = ~[];
let mut i = size;
while i > 0u {
let shift = ((i - 1u) * 8u) as u64;
bytes.push((n >> shift) as u8);
i -= 1u;
}
f(bytes)
}
}
}
pub fn u64_from_be_bytes(data: &[u8],
start: uint,
size: uint)
-> u64 {
let mut sz = size;
assert!((sz <= 8u));
let mut val = 0_u64;
let mut pos = start;
while sz > 0u {
sz -= 1u;
val += (data[pos] as u64) << ((sz * 8u) as u64);
pos += 1u;
}
return val;
}
// FIXME: #3048 combine trait+impl (or just move these to
// default methods on writer)
/// Generic utility functions defined on writers.
pub trait WriterUtil {
/// Write a single utf-8 encoded char.
fn write_char(&self, ch: char);
/// Write every char in the given str, encoded as utf-8.
fn write_str(&self, s: &str);
/// Write the given str, as utf-8, followed by '\n'.
fn write_line(&self, s: &str);
/// Write the result of passing n through `int::to_str_bytes`.
fn write_int(&self, n: int);
/// Write the result of passing n through `uint::to_str_bytes`.
fn write_uint(&self, n: uint);
/// Write a little-endian uint (number of bytes depends on system).
fn write_le_uint(&self, n: uint);
/// Write a little-endian int (number of bytes depends on system).
fn write_le_int(&self, n: int);
/// Write a big-endian uint (number of bytes depends on system).
fn write_be_uint(&self, n: uint);
/// Write a big-endian int (number of bytes depends on system).
fn write_be_int(&self, n: int);
/// Write a big-endian u64 (8 bytes).
fn write_be_u64(&self, n: u64);
/// Write a big-endian u32 (4 bytes).
fn write_be_u32(&self, n: u32);
/// Write a big-endian u16 (2 bytes).
fn write_be_u16(&self, n: u16);
/// Write a big-endian i64 (8 bytes).
fn write_be_i64(&self, n: i64);
/// Write a big-endian i32 (4 bytes).
fn write_be_i32(&self, n: i32);
/// Write a big-endian i16 (2 bytes).
fn write_be_i16(&self, n: i16);
/// Write a big-endian IEEE754 double-precision floating-point (8 bytes).
fn write_be_f64(&self, f: f64);
/// Write a big-endian IEEE754 single-precision floating-point (4 bytes).
fn write_be_f32(&self, f: f32);
/// Write a little-endian u64 (8 bytes).
fn write_le_u64(&self, n: u64);
/// Write a little-endian u32 (4 bytes).
fn write_le_u32(&self, n: u32);
/// Write a little-endian u16 (2 bytes).
fn write_le_u16(&self, n: u16);
/// Write a little-endian i64 (8 bytes).
fn write_le_i64(&self, n: i64);
/// Write a little-endian i32 (4 bytes).
fn write_le_i32(&self, n: i32);
/// Write a little-endian i16 (2 bytes).
fn write_le_i16(&self, n: i16);
/// Write a little-endian IEEE754 double-precision floating-point
/// (8 bytes).
fn write_le_f64(&self, f: f64);
/// Write a litten-endian IEEE754 single-precision floating-point
/// (4 bytes).
fn write_le_f32(&self, f: f32);
/// Write a u8 (1 byte).
fn write_u8(&self, n: u8);
/// Write a i8 (1 byte).
fn write_i8(&self, n: i8);
}
impl<T:Writer> WriterUtil for T {
fn write_char(&self, ch: char) {
if (ch as uint) < 128u {
self.write(&[ch as u8]);
} else {
self.write_str(str::from_char(ch));
}
}
fn write_str(&self, s: &str) { self.write(s.as_bytes()) }
fn write_line(&self, s: &str) {
self.write_str(s);
self.write_str(&"\n");
}
fn write_int(&self, n: int) {
int::to_str_bytes(n, 10u, |bytes| self.write(bytes))
}
fn write_uint(&self, n: uint) {
uint::to_str_bytes(n, 10u, |bytes| self.write(bytes))
}
fn write_le_uint(&self, n: uint) {
u64_to_le_bytes(n as u64, uint::bytes, |v| self.write(v))
}
fn write_le_int(&self, n: int) {
u64_to_le_bytes(n as u64, int::bytes, |v| self.write(v))
}
fn write_be_uint(&self, n: uint) {
u64_to_be_bytes(n as u64, uint::bytes, |v| self.write(v))
}
fn write_be_int(&self, n: int) {
u64_to_be_bytes(n as u64, int::bytes, |v| self.write(v))
}
fn write_be_u64(&self, n: u64) {
u64_to_be_bytes(n, 8u, |v| self.write(v))
}
fn write_be_u32(&self, n: u32) {
u64_to_be_bytes(n as u64, 4u, |v| self.write(v))
}
fn write_be_u16(&self, n: u16) {
u64_to_be_bytes(n as u64, 2u, |v| self.write(v))
}
fn write_be_i64(&self, n: i64) {
u64_to_be_bytes(n as u64, 8u, |v| self.write(v))
}
fn write_be_i32(&self, n: i32) {
u64_to_be_bytes(n as u64, 4u, |v| self.write(v))
}
fn write_be_i16(&self, n: i16) {
u64_to_be_bytes(n as u64, 2u, |v| self.write(v))
}
fn write_be_f64(&self, f:f64) {
unsafe {
self.write_be_u64(cast::transmute(f))
}
}
fn write_be_f32(&self, f:f32) {
unsafe {
self.write_be_u32(cast::transmute(f))
}
}
fn write_le_u64(&self, n: u64) {
u64_to_le_bytes(n, 8u, |v| self.write(v))
}
fn write_le_u32(&self, n: u32) {
u64_to_le_bytes(n as u64, 4u, |v| self.write(v))
}
fn write_le_u16(&self, n: u16) {
u64_to_le_bytes(n as u64, 2u, |v| self.write(v))
}
fn write_le_i64(&self, n: i64) {
u64_to_le_bytes(n as u64, 8u, |v| self.write(v))
}
fn write_le_i32(&self, n: i32) {
u64_to_le_bytes(n as u64, 4u, |v| self.write(v))
}
fn write_le_i16(&self, n: i16) {
u64_to_le_bytes(n as u64, 2u, |v| self.write(v))
}
fn write_le_f64(&self, f:f64) {
unsafe {
self.write_le_u64(cast::transmute(f))
}
}
fn write_le_f32(&self, f:f32) {
unsafe {
self.write_le_u32(cast::transmute(f))
}
}
fn write_u8(&self, n: u8) { self.write([n]) }
fn write_i8(&self, n: i8) { self.write([n as u8]) }
}
pub fn file_writer(path: &Path, flags: &[FileFlag]) -> Result<@Writer, ~str> {
mk_file_writer(path, flags).chain(|w| result::Ok(w))
}
// FIXME: fileflags // #2004
pub fn buffered_file_writer(path: &Path) -> Result<@Writer, ~str> {
unsafe {
let f = do path.to_str().as_c_str |pathbuf| {
do "w".as_c_str |modebuf| {
libc::fopen(pathbuf, modebuf)
}
};
return if f as uint == 0u {
result::Err(~"error opening " + path.to_str())
} else {
result::Ok(FILE_writer(f, true))
}
}
}
// FIXME (#2004) it would be great if this could be a const
// FIXME (#2004) why are these different from the way stdin() is
// implemented?
/**
* Gives a `Writer` which allows you to write to the standard output.
*
* # Example
*
* ~~~ {.rust}
* let stdout = core::io::stdout();
* stdout.write_str("hello\n");
* ~~~
*/
pub fn stdout() -> @Writer { fd_writer(libc::STDOUT_FILENO as c_int, false) }
/**
* Gives a `Writer` which allows you to write to standard error.
*
* # Example
*
* ~~~ {.rust}
* let stderr = core::io::stderr();
* stderr.write_str("hello\n");
* ~~~
*/
pub fn stderr() -> @Writer { fd_writer(libc::STDERR_FILENO as c_int, false) }
/**
* Prints a string to standard output.
*
* This string will not have an implicit newline at the end. If you want
* an implicit newline, please see `println`.
*
* # Example
*
* ~~~ {.rust}
* // print is imported into the prelude, and so is always available.
* print("hello");
* ~~~
*/
pub fn print(s: &str) {
stdout().write_str(s);
}
/**
* Prints a string to standard output, followed by a newline.
*
* If you do not want an implicit newline, please see `print`.
*
* # Example
*
* ~~~ {.rust}
* // println is imported into the prelude, and so is always available.
* println("hello");
* ~~~
*/
pub fn println(s: &str) {
stdout().write_line(s);
}
pub struct BytesWriter {
bytes: @mut ~[u8],
pos: @mut uint,
}
impl BytesWriter {
pub fn new() -> BytesWriter {
BytesWriter {
bytes: @mut ~[],
pos: @mut 0
}
}
}
impl Writer for BytesWriter {
fn write(&self, v: &[u8]) {
let v_len = v.len();
let bytes = &mut *self.bytes;
let count = num::max(bytes.len(), *self.pos + v_len);
bytes.reserve(count);
unsafe {
vec::raw::set_len(bytes, count);
let view = bytes.mut_slice(*self.pos, count);
vec::bytes::copy_memory(view, v, v_len);
}
*self.pos += v_len;
}
fn seek(&self, offset: int, whence: SeekStyle) {
let pos = *self.pos;
let len = self.bytes.len();
*self.pos = seek_in_buf(offset, pos, len, whence);
}
fn tell(&self) -> uint {
*self.pos
}
fn flush(&self) -> int {
0
}
fn get_type(&self) -> WriterType {
File
}
}
pub fn with_bytes_writer(f: &fn(@Writer)) -> ~[u8] {
let wr = @BytesWriter::new();
f(wr as @Writer);
let @BytesWriter { bytes, _ } = wr;
(*bytes).clone()
}
pub fn with_str_writer(f: &fn(@Writer)) -> ~str {
let mut v = with_bytes_writer(f);
// Make sure the vector has a trailing null and is proper utf8.
v.push(0);
assert!(str::is_utf8(v));
unsafe {
::cast::transmute(v)
}
}
// Utility functions
pub fn seek_in_buf(offset: int, pos: uint, len: uint, whence: SeekStyle) ->
uint {
let mut bpos = pos as int;
let blen = len as int;
match whence {
SeekSet => bpos = offset,
SeekCur => bpos += offset,
SeekEnd => bpos = blen + offset
}
if bpos < 0 { bpos = 0; } else if bpos > blen { bpos = blen; }
return bpos as uint;
}
pub fn read_whole_file_str(file: &Path) -> Result<~str, ~str> {
result::chain(read_whole_file(file), |bytes| {
if str::is_utf8(bytes) {
result::Ok(str::from_bytes(bytes))
} else {
result::Err(file.to_str() + " is not UTF-8")
}
})
}
// FIXME (#2004): implement this in a low-level way. Going through the
// abstractions is pointless.
pub fn read_whole_file(file: &Path) -> Result<~[u8], ~str> {
result::chain(file_reader(file), |rdr| {
result::Ok(rdr.read_whole_stream())
})
}
// fsync related
pub mod fsync {
use io::{FILERes, FdRes, fd_t};
use libc;
use ops::Drop;
use option::{None, Option, Some};
use os;
pub enum Level {
// whatever fsync does on that platform
FSync,
// fdatasync on linux, similiar or more on other platforms
FDataSync,
// full fsync
//
// You must additionally sync the parent directory as well!
FullFSync,
}
// Artifacts that need to fsync on destruction
pub struct Res<t> {
arg: Arg<t>,
}
impl <t> Res<t> {
pub fn new(arg: Arg<t>) -> Res<t> {
Res { arg: arg }
}
}
#[unsafe_destructor]
impl<T> Drop for Res<T> {
fn drop(&self) {
match self.arg.opt_level {
None => (),
Some(level) => {
// fail hard if not succesful
assert!(((self.arg.fsync_fn)(&self.arg.val, level) != -1));
}
}
}
}
pub struct Arg<t> {
val: t,
opt_level: Option<Level>,
fsync_fn: @fn(f: &t, Level) -> int,
}
// fsync file after executing blk
// FIXME (#2004) find better way to create resources within lifetime of
// outer res
pub fn FILE_res_sync(file: &FILERes, opt_level: Option<Level>,
blk: &fn(v: Res<*libc::FILE>)) {
blk(Res::new(Arg {
val: file.f, opt_level: opt_level,
fsync_fn: |file, l| {
unsafe {
os::fsync_fd(libc::fileno(*file), l) as int
}
}
}));
}
// fsync fd after executing blk
pub fn fd_res_sync(fd: &FdRes, opt_level: Option<Level>,
blk: &fn(v: Res<fd_t>)) {
blk(Res::new(Arg {
val: fd.fd, opt_level: opt_level,
fsync_fn: |fd, l| os::fsync_fd(*fd, l) as int
}));
}
// Type of objects that may want to fsync
pub trait FSyncable { fn fsync(&self, l: Level) -> int; }
// Call o.fsync after executing blk
pub fn obj_sync(o: @FSyncable, opt_level: Option<Level>,
blk: &fn(v: Res<@FSyncable>)) {
blk(Res::new(Arg {
val: o, opt_level: opt_level,
fsync_fn: |o, l| (*o).fsync(l)
}));
}
}
#[cfg(test)]
mod tests {
use i32;
use io::{BytesWriter, SeekCur, SeekEnd, SeekSet};
use io;
use path::Path;
use result;
use u64;
use vec;
#[test]
fn test_simple() {
let tmpfile = &Path("tmp/lib-io-test-simple.tmp");
debug!(tmpfile);
let frood: ~str =
~"A hoopy frood who really knows where his towel is.";
debug!(frood.clone());
{
let out: @io::Writer =
result::unwrap(
io::file_writer(tmpfile, [io::Create, io::Truncate]));
out.write_str(frood);
}
let inp: @io::Reader = result::unwrap(io::file_reader(tmpfile));
let frood2: ~str = inp.read_c_str();
debug!(frood2.clone());
assert_eq!(frood, frood2);
}
#[test]
fn test_readchars_empty() {
do io::with_str_reader("") |inp| {
let res : ~[char] = inp.read_chars(128);
assert_eq!(res.len(), 0);
}
}
#[test]
fn test_read_line_utf8() {
do io::with_str_reader("生锈的汤匙切肉汤hello生锈的汤匙切肉汤") |inp| {
let line = inp.read_line();
assert_eq!(line, ~"生锈的汤匙切肉汤hello生锈的汤匙切肉汤");
}
}
#[test]
fn test_read_lines() {
do io::with_str_reader("a\nb\nc\n") |inp| {
assert_eq!(inp.read_lines(), ~[~"a", ~"b", ~"c"]);
}
do io::with_str_reader("a\nb\nc") |inp| {
assert_eq!(inp.read_lines(), ~[~"a", ~"b", ~"c"]);
}
do io::with_str_reader("") |inp| {
assert!(inp.read_lines().is_empty());
}
}
#[test]
fn test_readchars_wide() {
let wide_test = ~"生锈的汤匙切肉汤hello生锈的汤匙切肉汤";
let ivals : ~[int] = ~[
29983, 38152, 30340, 27748,
21273, 20999, 32905, 27748,
104, 101, 108, 108, 111,
29983, 38152, 30340, 27748,
21273, 20999, 32905, 27748];
fn check_read_ln(len : uint, s: &str, ivals: &[int]) {
do io::with_str_reader(s) |inp| {
let res : ~[char] = inp.read_chars(len);
if len <= ivals.len() {
assert_eq!(res.len(), len);
}
for ivals.iter().zip(res.iter()).advance |(iv, c)| {
assert!(*iv == *c as int)
}
}
}
let mut i = 0;
while i < 8 {
check_read_ln(i, wide_test, ivals);
i += 1;
}
// check a long read for good measure
check_read_ln(128, wide_test, ivals);
}
#[test]
fn test_readchar() {
do io::with_str_reader("") |inp| {
let res : char = inp.read_char();
assert_eq!(res as int, 29983);
}
}
#[test]
fn test_readchar_empty() {
do io::with_str_reader("") |inp| {
let res : char = inp.read_char();
assert_eq!(res as int, -1);
}
}
#[test]
fn file_reader_not_exist() {
match io::file_reader(&Path("not a file")) {
result::Err(e) => {
assert_eq!(e, ~"error opening not a file");
}
result::Ok(_) => fail!()
}
}
#[test]
#[should_fail]
#[ignore(cfg(windows))]
fn test_read_buffer_too_small() {
let path = &Path("tmp/lib-io-test-read-buffer-too-small.tmp");
// ensure the file exists
io::file_writer(path, [io::Create]).unwrap();
let file = io::file_reader(path).unwrap();
let mut buf = vec::from_elem(5, 0u8);
file.read(buf, 6); // this should fail because buf is too small
}
#[test]
fn test_read_buffer_big_enough() {
let path = &Path("tmp/lib-io-test-read-buffer-big-enough.tmp");
// ensure the file exists
io::file_writer(path, [io::Create]).unwrap();
let file = io::file_reader(path).unwrap();
let mut buf = vec::from_elem(5, 0u8);
file.read(buf, 4); // this should succeed because buf is big enough
}
#[test]
fn test_write_empty() {
let file = io::file_writer(&Path("tmp/lib-io-test-write-empty.tmp"),
[io::Create]).unwrap();
file.write([]);
}
#[test]
fn file_writer_bad_name() {
match io::file_writer(&Path("?/?"), []) {
result::Err(e) => {
assert!(e.starts_with("error opening"));
}
result::Ok(_) => fail!()
}
}
#[test]
fn buffered_file_writer_bad_name() {
match io::buffered_file_writer(&Path("?/?")) {
result::Err(e) => {
assert!(e.starts_with("error opening"));
}
result::Ok(_) => fail!()
}
}
#[test]
fn bytes_buffer_overwrite() {
let wr = BytesWriter::new();
wr.write([0u8, 1u8, 2u8, 3u8]);
assert!(*wr.bytes == ~[0u8, 1u8, 2u8, 3u8]);
wr.seek(-2, SeekCur);
wr.write([4u8, 5u8, 6u8, 7u8]);
assert!(*wr.bytes == ~[0u8, 1u8, 4u8, 5u8, 6u8, 7u8]);
wr.seek(-2, SeekEnd);
wr.write([8u8]);
wr.seek(1, SeekSet);
wr.write([9u8]);
assert!(*wr.bytes == ~[0u8, 9u8, 4u8, 5u8, 8u8, 7u8]);
}
#[test]
fn test_read_write_le() {
let path = Path("tmp/lib-io-test-read-write-le.tmp");
let uints = [0, 1, 2, 42, 10_123, 100_123_456, u64::max_value];
// write the ints to the file
{
let file = io::file_writer(&path, [io::Create]).unwrap();
for uints.iter().advance |i| {
file.write_le_u64(*i);
}
}
// then read them back and check that they are the same
{
let file = io::file_reader(&path).unwrap();
for uints.iter().advance |i| {
assert_eq!(file.read_le_u64(), *i);
}
}
}
#[test]
fn test_read_write_be() {
let path = Path("tmp/lib-io-test-read-write-be.tmp");
let uints = [0, 1, 2, 42, 10_123, 100_123_456, u64::max_value];
// write the ints to the file
{
let file = io::file_writer(&path, [io::Create]).unwrap();
for uints.iter().advance |i| {
file.write_be_u64(*i);
}
}
// then read them back and check that they are the same
{
let file = io::file_reader(&path).unwrap();
for uints.iter().advance |i| {
assert_eq!(file.read_be_u64(), *i);
}
}
}
#[test]
fn test_read_be_int_n() {
let path = Path("tmp/lib-io-test-read-be-int-n.tmp");
let ints = [i32::min_value, -123456, -42, -5, 0, 1, i32::max_value];
// write the ints to the file
{
let file = io::file_writer(&path, [io::Create]).unwrap();
for ints.iter().advance |i| {
file.write_be_i32(*i);
}
}
// then read them back and check that they are the same
{
let file = io::file_reader(&path).unwrap();
for ints.iter().advance |i| {
// this tests that the sign extension is working
// (comparing the values as i32 would not test this)
assert_eq!(file.read_be_int_n(4), *i as i64);
}
}
}
#[test]
fn test_read_f32() {
let path = Path("tmp/lib-io-test-read-f32.tmp");
//big-endian floating-point 8.1250
let buf = ~[0x41, 0x02, 0x00, 0x00];
{
let file = io::file_writer(&path, [io::Create]).unwrap();
file.write(buf);
}
{
let file = io::file_reader(&path).unwrap();
let f = file.read_be_f32();
assert_eq!(f, 8.1250);
}
}
#[test]
fn test_read_write_f32() {
let path = Path("tmp/lib-io-test-read-write-f32.tmp");
let f:f32 = 8.1250;
{
let file = io::file_writer(&path, [io::Create]).unwrap();
file.write_be_f32(f);
file.write_le_f32(f);
}
{
let file = io::file_reader(&path).unwrap();
assert_eq!(file.read_be_f32(), 8.1250);
assert_eq!(file.read_le_f32(), 8.1250);
}
}
}