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use symbol_table::Entry;
use zero::Pod;
#[derive(Debug)]
#[repr(C)]
pub struct HashTable {
bucket_count: u32,
chain_count: u32,
first_bucket: u32,
}
unsafe impl Pod for HashTable {}
pub fn hash(input: &str) -> u32 {
let mut result = 0;
for i in input.bytes() {
result = (result << 4) + i as u32;
let g = result & 0xf0000000;
if g != 0 {
result ^= g >> 24;
}
result &= !g
}
result
}
impl HashTable {
pub fn get_bucket(&self, index: u32) -> u32 {
assert!(index < self.bucket_count);
unsafe {
let ptr = (&self.first_bucket as *const u32).offset(index as isize);
*ptr
}
}
pub fn get_chain(&self, index: u32) -> u32 {
assert!(index < self.chain_count);
let index = self.bucket_count + index;
unsafe {
let ptr = (&self.first_bucket as *const u32).offset(index as isize);
*ptr
}
}
pub fn lookup<'a, F>(&'a self, name: &str, f: F) -> &'a Entry
where F: Fn(&'a Entry) -> bool
{
unimplemented!();
}
}