1 | #pragma once |
2 | |
3 | #include <algorithm> |
4 | #include <Processors/Chunk.h> |
5 | #include <Columns/IColumn.h> |
6 | #include <boost/smart_ptr/intrusive_ptr.hpp> |
7 | |
8 | |
9 | namespace DB |
10 | { |
11 | |
12 | /// Allows you refer to the row in the block and hold the block ownership, |
13 | /// and thus avoid creating a temporary row object. |
14 | /// Do not use std::shared_ptr, since there is no need for a place for `weak_count` and `deleter`; |
15 | /// does not use Poco::SharedPtr, since you need to allocate a block and `refcount` in one piece; |
16 | /// does not use Poco::AutoPtr, since it does not have a `move` constructor and there are extra checks for nullptr; |
17 | /// The reference counter is not atomic, since it is used from one thread. |
18 | namespace detail |
19 | { |
20 | struct SharedChunk : Chunk |
21 | { |
22 | int refcount = 0; |
23 | |
24 | ColumnRawPtrs all_columns; |
25 | ColumnRawPtrs sort_columns; |
26 | |
27 | SharedChunk(Chunk && chunk) : Chunk(std::move(chunk)) {} |
28 | }; |
29 | |
30 | } |
31 | |
32 | inline void intrusive_ptr_add_ref(detail::SharedChunk * ptr) |
33 | { |
34 | ++ptr->refcount; |
35 | } |
36 | |
37 | inline void intrusive_ptr_release(detail::SharedChunk * ptr) |
38 | { |
39 | if (0 == --ptr->refcount) |
40 | delete ptr; |
41 | } |
42 | |
43 | using SharedChunkPtr = boost::intrusive_ptr<detail::SharedChunk>; |
44 | |
45 | |
46 | struct SharedChunkRowRef |
47 | { |
48 | ColumnRawPtrs * columns = nullptr; |
49 | size_t row_num; |
50 | SharedChunkPtr shared_block; |
51 | |
52 | void swap(SharedChunkRowRef & other) |
53 | { |
54 | std::swap(columns, other.columns); |
55 | std::swap(row_num, other.row_num); |
56 | std::swap(shared_block, other.shared_block); |
57 | } |
58 | |
59 | /// The number and types of columns must match. |
60 | bool operator==(const SharedChunkRowRef & other) const |
61 | { |
62 | size_t size = columns->size(); |
63 | for (size_t i = 0; i < size; ++i) |
64 | if (0 != (*columns)[i]->compareAt(row_num, other.row_num, *(*other.columns)[i], 1)) |
65 | return false; |
66 | return true; |
67 | } |
68 | |
69 | bool operator!=(const SharedChunkRowRef & other) const |
70 | { |
71 | return !(*this == other); |
72 | } |
73 | |
74 | void reset() |
75 | { |
76 | SharedChunkRowRef empty; |
77 | swap(empty); |
78 | } |
79 | |
80 | bool empty() const { return columns == nullptr; } |
81 | size_t size() const { return empty() ? 0 : columns->size(); } |
82 | |
83 | void set(SharedChunkPtr & shared_block_, ColumnRawPtrs * columns_, size_t row_num_) |
84 | { |
85 | shared_block = shared_block_; |
86 | columns = columns_; |
87 | row_num = row_num_; |
88 | } |
89 | }; |
90 | |
91 | } |
92 | |