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use std::borrow::Borrow;
use std::collections::HashMap;
use std::ffi::{CStr, CString};
use std::str::from_utf8_unchecked;
use std::ptr;
extern crate libc;
use libc::c_char;
pub mod c;
pub use c::*;
pub struct StringMap {
keys: Vec<*const c_char>,
data: HashMap<CString, CString>,
}
impl StringMap {
pub fn new<'input, P, S, T>(tuples: T) -> StringMap
where P: Borrow<(S, S)>,
S: Borrow<str>,
T: IntoIterator<Item = P>
{
let mut keys: Vec<*const c_char> = Vec::default();
let mut data: HashMap<CString, CString> = HashMap::default();
for pair in tuples {
let &(ref k, ref v) = pair.borrow();
if let Ok(k) = CString::new(k.borrow()) {
if let Ok(v) = CString::new(v.borrow()) {
keys.push(k.as_ptr() as *const c_char);
data.insert(k, v);
}
}
}
keys.push(ptr::null());
StringMap { keys: keys, data: data }
}
pub fn keys(&self) -> Vec<&str> {
self.keys[0..(self.keys.len() - 1)]
.iter()
.map(|&p| unsafe { CStr::from_ptr(p) })
.map(|s| unsafe { from_utf8_unchecked(s.to_bytes()) })
.collect()
}
pub fn get(&self, key: &str) -> Option<&str> {
if let Ok(ref k) = CString::new(key) {
self.data
.get(k)
.map(|s| unsafe { from_utf8_unchecked(s.as_bytes()) })
} else {
None
}
}
pub fn len(&self) -> usize { self.data.len() }
}
#[cfg(test)]
mod tests {
use libc::c_char;
use ::c::*;
use ::StringMap;
#[test]
fn it_works() {
let data = vec![("a", "A"), ("b", "B")];
let m = StringMap::new(&data);
assert!(m.len() == 2);
assert!(m.keys() == vec!["a", "b"]);
assert!(m.get("a") == Some("A"));
assert!(m.get("b") == Some("B"));
}
#[test]
fn extern_basics() {
let data = vec![("a", "A"), ("b", "B")];
let keys: Vec<*const c_char> =
data.iter().map(|&(s, _)| s.as_ptr() as *const c_char).collect();
let vals: Vec<*const c_char> =
data.iter().map(|&(_, s)| s.as_ptr() as *const c_char).collect();
unsafe {
let m = stringmap_new(data.len(), keys.as_ptr(), vals.as_ptr());
assert!(stringmap_len(m) == 2);
assert!(!stringmap_keys(m).is_null());
stringmap_free(m);
}
}
}