forked from npgsql/npgsql
-
Notifications
You must be signed in to change notification settings - Fork 0
Expand file tree
/
Copy pathNpgsqlLengthCache.cs
More file actions
67 lines (59 loc) · 2 KB
/
NpgsqlLengthCache.cs
File metadata and controls
67 lines (59 loc) · 2 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
using System.Collections.Generic;
using System.Diagnostics;
using Npgsql.TypeHandling;
namespace Npgsql
{
/// <summary>
/// An array of cached lengths for the parameters sending process.
///
/// When sending parameters, lengths need to be calculated more than once (once for Bind, once for
/// an array, once for the string within that array). This cache optimized that. Lengths are added
/// to the cache, and then retrieved at the same order.
/// </summary>
public sealed class NpgsqlLengthCache
{
internal bool IsPopulated;
internal int Position;
internal List<int> Lengths;
internal NpgsqlLengthCache() => Lengths = new List<int>();
internal NpgsqlLengthCache(int capacity) => Lengths = new List<int>(capacity);
/// <summary>
/// Stores a length value in the cache, to be fetched later via <see cref="Get"/>.
/// Called at the <see cref="NpgsqlTypeHandler.ValidateAndGetLength{TAny}"/> phase.
/// </summary>
/// <returns>The length parameter.</returns>
public int Set(int len)
{
Debug.Assert(!IsPopulated);
Lengths.Add(len);
Position++;
return len;
}
/// <summary>
/// Retrieves a length value previously stored in the cache via <see cref="Set(int)"/>.
/// Called at the writing phase, after validation has already occurred and the length cache is populated.
/// </summary>
/// <returns></returns>
public int Get()
{
Debug.Assert(IsPopulated);
return Lengths[Position++];
}
internal int GetLast()
{
Debug.Assert(IsPopulated);
return Lengths[Position-1];
}
internal void Rewind()
{
Position = 0;
IsPopulated = true;
}
internal void Clear()
{
Lengths.Clear();
Position = 0;
IsPopulated = false;
}
}
}