ckb_rocksdb/ops/
merge.rs

1use crate::ffi;
2use libc::{c_char, size_t};
3
4use crate::{handle::Handle, ColumnFamily, Error, WriteOptions};
5
6pub trait Merge<W> {
7    fn merge_full<K, V>(&self, key: K, value: V, writeopts: Option<&W>) -> Result<(), Error>
8    where
9        K: AsRef<[u8]>,
10        V: AsRef<[u8]>;
11
12    fn merge<K, V>(&self, key: K, value: V) -> Result<(), Error>
13    where
14        K: AsRef<[u8]>,
15        V: AsRef<[u8]>,
16    {
17        self.merge_full(key, value, None)
18    }
19
20    fn merge_opt<K, V>(&self, key: K, value: V, writeopts: &W) -> Result<(), Error>
21    where
22        K: AsRef<[u8]>,
23        V: AsRef<[u8]>,
24    {
25        self.merge_full(key, value, Some(writeopts))
26    }
27}
28
29pub trait MergeCF<W> {
30    fn merge_cf_full<K, V>(
31        &self,
32        cf: Option<&ColumnFamily>,
33        key: K,
34        value: V,
35        writeopts: Option<&W>,
36    ) -> Result<(), Error>
37    where
38        K: AsRef<[u8]>,
39        V: AsRef<[u8]>;
40
41    fn merge_cf<K, V>(&self, cf: &ColumnFamily, key: K, value: V) -> Result<(), Error>
42    where
43        K: AsRef<[u8]>,
44        V: AsRef<[u8]>,
45    {
46        self.merge_cf_full(Some(cf), key, value, None)
47    }
48
49    fn merge_cf_opt<K, V>(
50        &self,
51        cf: &ColumnFamily,
52        key: K,
53        value: V,
54        writeopts: &W,
55    ) -> Result<(), Error>
56    where
57        K: AsRef<[u8]>,
58        V: AsRef<[u8]>,
59    {
60        self.merge_cf_full(Some(cf), key, value, Some(writeopts))
61    }
62}
63
64impl<T, W> Merge<W> for T
65where
66    T: MergeCF<W>,
67{
68    fn merge_full<K: AsRef<[u8]>, V: AsRef<[u8]>>(
69        &self,
70        key: K,
71        value: V,
72        writeopts: Option<&W>,
73    ) -> Result<(), Error> {
74        self.merge_cf_full(None, key, value, writeopts)
75    }
76}
77
78impl<T> MergeCF<WriteOptions> for T
79where
80    T: Handle<ffi::rocksdb_t> + super::Write,
81{
82    fn merge_cf_full<K, V>(
83        &self,
84        cf: Option<&ColumnFamily>,
85        key: K,
86        value: V,
87        writeopts: Option<&WriteOptions>,
88    ) -> Result<(), Error>
89    where
90        K: AsRef<[u8]>,
91        V: AsRef<[u8]>,
92    {
93        let mut default_writeopts = None;
94
95        let wo_handle = WriteOptions::input_or_default(writeopts, &mut default_writeopts)?;
96
97        let key = key.as_ref();
98        let value = value.as_ref();
99        let key_ptr = key.as_ptr() as *const c_char;
100        let key_len = key.len() as size_t;
101        let val_ptr = value.as_ptr() as *const c_char;
102        let val_len = value.len() as size_t;
103
104        unsafe {
105            match cf {
106                Some(cf) => ffi_try!(ffi::rocksdb_merge_cf(
107                    self.handle(),
108                    wo_handle,
109                    cf.handle(),
110                    key_ptr,
111                    key_len,
112                    val_ptr,
113                    val_len,
114                )),
115                None => ffi_try!(ffi::rocksdb_merge(
116                    self.handle(),
117                    wo_handle,
118                    key_ptr,
119                    key_len,
120                    val_ptr,
121                    val_len,
122                )),
123            }
124
125            Ok(())
126        }
127    }
128}