1use std::{mem, ptr, sync::Arc};
2
3use crate::{StorageExt, StorageExtStr, StorageVTable};
4
5fn as_ptr(addr: *const u8, _: usize) -> *const u8 {
8 addr
9}
10
11fn len(_: *const u8, len: usize) -> usize {
12 len
13}
14
15fn clone_str(addr: *const u8, len: usize) -> Option<(*const u8, usize)> {
16 let slice_ptr: *const [u8] = ptr::slice_from_raw_parts(addr, len);
17 let str_ptr = slice_ptr as *const str;
18 let arc = unsafe { Arc::from_raw(str_ptr) };
19 let arc2 = arc.clone();
20 mem::forget(arc);
21 mem::forget(arc2);
22
23 Some((addr, len))
24}
25
26fn drop_str(addr: *const u8, len: usize) {
27 let slice_ptr: *const [u8] = ptr::slice_from_raw_parts(addr, len);
28 let str_ptr = slice_ptr as *const str;
29 let arc = unsafe { Arc::from_raw(str_ptr) };
30 drop(arc);
31}
32
33const ARC_STR_VTABLE: StorageVTable = StorageVTable::new(as_ptr, len, clone_str, drop_str);
34
35impl StorageExt for Arc<str> {
36 fn create(self) -> (*const u8, usize, &'static StorageVTable) {
37 let ptr = Arc::into_raw(self) as *const [u8];
38
39 let addr = ptr.cast::<()>().cast::<u8>();
41 let len = ptr.len();
42 (addr, len, &ARC_STR_VTABLE)
43 }
44}
45
46unsafe impl StorageExtStr for Arc<str> {}
49
50#[cfg(test)]
51#[allow(unused_must_use)]
52mod tests {
53 use super::*;
54 use crate::{ByteString, Bytes, buf::Buf};
55
56 #[test]
57 fn test_arc_str() {
58 let test: Arc<str> = Arc::from("test".to_string());
59
60 let b = Bytes::from_ext(test.clone());
61 assert_eq!(&b, b"test");
62 assert_eq!(b.storage.capacity(), 4);
63 assert_eq!(Arc::strong_count(&test), 2);
64
65 let b2 = b.clone();
66 assert_eq!(&b2, b"test");
67 assert_eq!(Arc::strong_count(&test), 3);
68
69 drop(b2);
70 assert_eq!(&b, b"test");
71 assert_eq!(Arc::strong_count(&test), 2);
72
73 drop(b);
74 assert_eq!(Arc::strong_count(&test), 1);
75
76 let b = ByteString::from_ext(test.clone());
77 assert_eq!(&b, "test");
78 assert_eq!(Arc::strong_count(&test), 2);
79
80 drop(b);
81 assert_eq!(Arc::strong_count(&test), 1);
82
83 let mut b = Bytes::from_ext(test.clone());
84 assert_eq!(Arc::strong_count(&test), 2);
85 assert_eq!(b.get_u8(), b't');
86 assert_eq!(&b, b"est");
87 assert_eq!(Arc::strong_count(&test), 1);
88
89 let mut b = Bytes::from_ext(test.clone());
90 b.truncate(2);
91 assert_eq!(&b, b"te");
92 assert_eq!(Arc::strong_count(&test), 1);
93
94 let mut b = Bytes::from_ext(test.clone());
95 unsafe { b.storage.set_start(2) };
96 assert_eq!(&b, b"st");
97 assert_eq!(Arc::strong_count(&test), 1);
98
99 let mut b = Bytes::from_ext(test.clone());
100 unsafe { b.storage.set_end(2) };
101 assert_eq!(&b, b"te");
102 assert_eq!(Arc::strong_count(&test), 1);
103 }
104}