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
|
//===----------------------------------------------------------------------===//
//
// This source file is part of the Swift open source project
//
// Copyright (c) 2023-2024 Apple Inc. and the Swift project authors
// Licensed under Apache License v2.0 with Runtime Library Exception
//
// See https://swift.org/LICENSE.txt for license information
// See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
//
//===----------------------------------------------------------------------===//
internal import class Dispatch.DispatchQueue
internal import struct SystemPackage.FileDescriptor
/// A read-only thread-safe handle to an open file.
package struct OpenReadableFile: Sendable {
/// Maximum size of chunks in bytes produced when reading this file handle.
let chunkSize: Int
/// Underlying storage for this file handle, dependent on the file system type that produced it.
enum Storage {
/// Operating system file descriptor and a queue used for reading from that file descriptor without blocking
/// the Swift Concurrency thread pool.
case real(FileDescriptor, DispatchQueue)
/// Complete contents of the file represented by this handle stored in memory as an array of bytes.
case mock([UInt8])
}
/// Concrete instance of underlying file storage.
let fileHandle: Storage
/// Creates a readable ``AsyncSequence`` that can be iterated on to read from this file handle.
/// - Returns: `ReadableFileStream` value conforming to ``AsyncSequence``, ready for asynchronous iteration.
package func read() async throws -> ReadableFileStream {
switch self.fileHandle {
case let .real(fileDescriptor, ioQueue):
return ReadableFileStream.real(
.init(
fileDescriptor: fileDescriptor,
ioQueue: ioQueue,
readChunkSize: self.chunkSize
)
)
case .mock(let array):
return ReadableFileStream.mock(.init(bytes: array, chunkSize: self.chunkSize))
}
}
}
|
