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// Copyright 2013 The Servo Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// option. This file may not be copied, modified, or distributed
// except according to those terms.
//! Immutable strings.
pub use core_foundation_sys::string::*;
use crate::base::{CFIndexConvertible, TCFType};
use core_foundation_sys::base::{kCFAllocatorDefault, kCFAllocatorNull};
use core_foundation_sys::base::{Boolean, CFIndex, CFRange};
use std::borrow::Cow;
use std::ffi::CStr;
use std::fmt;
use std::ptr;
use std::str::{self, FromStr};
declare_TCFType! {
/// An immutable string in one of a variety of encodings.
CFString, CFStringRef
}
impl_TCFType!(CFString, CFStringRef, CFStringGetTypeID);
impl FromStr for CFString {
type Err = ();
/// See also [`CFString::new()`] for a variant of this which does not return a `Result`.
#[inline]
fn from_str(string: &str) -> Result<CFString, ()> {
Ok(CFString::new(string))
}
}
impl<'a> From<&'a str> for CFString {
#[inline]
fn from(string: &'a str) -> CFString {
CFString::new(string)
}
}
impl<'a> From<&'a CFString> for Cow<'a, str> {
fn from(cf_str: &'a CFString) -> Cow<'a, str> {
unsafe {
// Do this without allocating if we can get away with it
let c_string = CFStringGetCStringPtr(cf_str.0, kCFStringEncodingUTF8);
if !c_string.is_null() {
let c_str = CStr::from_ptr(c_string);
Cow::Borrowed(str::from_utf8_unchecked(c_str.to_bytes()))
} else {
let char_len = cf_str.char_len();
// First, ask how big the buffer ought to be.
let mut bytes_required: CFIndex = 0;
CFStringGetBytes(
cf_str.0,
CFRange {
location: 0,
length: char_len,
},
kCFStringEncodingUTF8,
0,
false as Boolean,
ptr::null_mut(),
0,
&mut bytes_required,
);
// Then, allocate the buffer and actually copy.
let mut buffer = vec![b'\x00'; bytes_required as usize];
let mut bytes_used: CFIndex = 0;
let chars_written = CFStringGetBytes(
cf_str.0,
CFRange {
location: 0,
length: char_len,
},
kCFStringEncodingUTF8,
0,
false as Boolean,
buffer.as_mut_ptr(),
buffer.len().to_CFIndex(),
&mut bytes_used,
);
assert_eq!(chars_written, char_len);
// This is dangerous; we over-allocate and null-terminate the string (during
// initialization).
assert_eq!(bytes_used, buffer.len().to_CFIndex());
Cow::Owned(String::from_utf8_unchecked(buffer))
}
}
}
}
impl fmt::Display for CFString {
fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
fmt.write_str(&Cow::from(self))
}
}
impl fmt::Debug for CFString {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
write!(f, "\"{}\"", self)
}
}
impl CFString {
/// Creates a new `CFString` instance from a Rust string.
#[inline]
pub fn new(string: &str) -> CFString {
unsafe {
let string_ref = CFStringCreateWithBytes(
kCFAllocatorDefault,
string.as_ptr(),
string.len().to_CFIndex(),
kCFStringEncodingUTF8,
false as Boolean,
);
CFString::wrap_under_create_rule(string_ref)
}
}
/// Like `CFString::new`, but references a string that can be used as a backing store
/// by virtue of being statically allocated.
#[inline]
pub fn from_static_string(string: &'static str) -> CFString {
unsafe {
let string_ref = CFStringCreateWithBytesNoCopy(
kCFAllocatorDefault,
string.as_ptr(),
string.len().to_CFIndex(),
kCFStringEncodingUTF8,
false as Boolean,
kCFAllocatorNull,
);
TCFType::wrap_under_create_rule(string_ref)
}
}
/// Returns the number of characters in the string.
#[inline]
pub fn char_len(&self) -> CFIndex {
unsafe { CFStringGetLength(self.0) }
}
}
impl<'a> PartialEq<&'a str> for CFString {
fn eq(&self, other: &&str) -> bool {
unsafe {
let temp = CFStringCreateWithBytesNoCopy(
kCFAllocatorDefault,
other.as_ptr(),
other.len().to_CFIndex(),
kCFStringEncodingUTF8,
false as Boolean,
kCFAllocatorNull,
);
self.eq(&CFString::wrap_under_create_rule(temp))
}
}
}
impl<'a> PartialEq<CFString> for &'a str {
#[inline]
fn eq(&self, other: &CFString) -> bool {
other.eq(self)
}
}
impl PartialEq<CFString> for String {
#[inline]
fn eq(&self, other: &CFString) -> bool {
other.eq(&self.as_str())
}
}
impl PartialEq<String> for CFString {
#[inline]
fn eq(&self, other: &String) -> bool {
self.eq(&other.as_str())
}
}
#[test]
fn str_cmp() {
let cfstr = CFString::new("hello");
assert_eq!("hello", cfstr);
assert_eq!(cfstr, "hello");
assert_ne!(cfstr, "wrong");
assert_ne!("wrong", cfstr);
let hello = String::from("hello");
assert_eq!(hello, cfstr);
assert_eq!(cfstr, hello);
}
#[test]
fn string_and_back() {
let original = "The quick brown fox jumped over the slow lazy dog.";
let cfstr = CFString::from_static_string(original);
let converted = cfstr.to_string();
assert_eq!(converted, original);
}