-
Notifications
You must be signed in to change notification settings - Fork 0
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
* Create Parser
- Loading branch information
Showing
14 changed files
with
20,424 additions
and
62 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,167 @@ | ||
| // Copyright (c) 2021 Jeff Lebrun | ||
| // | ||
| // Permission is hereby granted, free of charge, to any person obtaining a copy | ||
| // of this software and associated documentation files (the Software), to deal | ||
| // in the Software without restriction, including without limitation the rights | ||
| // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell | ||
| // copies of the Software, and to permit persons to whom the Software is | ||
| // furnished to do so, subject to the following conditions: | ||
| // | ||
| // The above copyright notice and this permission notice shall be included in all | ||
| // copies or substantial portions of the Software. | ||
| // | ||
| // THE SOFTWARE IS PROVIDED AS IS, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR | ||
| // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, | ||
| // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE | ||
| // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER | ||
| // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, | ||
| // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE | ||
| // SOFTWARE. | ||
|
|
||
| /// `ArArchiveReader` reads `ar` files. | ||
| public struct ArArchiveReader { | ||
| private var data: [UInt8] | ||
| private var currentIndex: Int = 0 | ||
|
|
||
| /// Used primarily when in a for loop: | ||
| /// | ||
| /// ```swift | ||
| /// let bytes = Array<UInt8>(try Data(contentsOf: myURL)) | ||
| /// let reader = try ArArchiveReader(archive: bytes) | ||
| /// for index = in 0..<reader.count { | ||
| /// let header = reader.headers[index] | ||
| /// let data = reader[header] | ||
| /// // Use data and header. | ||
| /// } | ||
| /// ``` | ||
| /// | ||
|
|
||
| /// The headers that describe the files in this archive. | ||
| /// | ||
| /// Use this to find a file in the archive, then use the provided subscript to get the bytes of the file. | ||
| /// | ||
| /// ```swift | ||
| /// let bytes = Array<UInt8>(try Data(contentsOf: myURL)) | ||
| /// let reader = try ArArchiveReader(archive: bytes) | ||
| /// let bytes = reader[reader.headers[0]] | ||
| /// // Use bytes... | ||
| /// ``` | ||
| /// | ||
| public var headers: [Header] = [] | ||
|
|
||
| /// The initializer reads all the `ar` headers in preparation for random access to the header's file contents later. | ||
| public init(archive: [UInt8]) throws { | ||
| if archive.isEmpty { | ||
| throw ArArchiveError.emptyArchive | ||
| } else if archive.count < 8 { | ||
| // The global header is missing. | ||
| throw ArArchiveError.invalidArchive | ||
| } else if Array(archive[0...7]) != globalHeader.asciiArray { | ||
| // The global header is invalid. | ||
| throw ArArchiveError.invalidArchive | ||
| } | ||
|
|
||
| // Drop the global header from the byte array. | ||
| self.data = Array(archive[8...]) | ||
|
|
||
| var index = 0 | ||
|
|
||
| // Read all the headers so we can provide random access to the data later. | ||
| while index < (self.data.count - 1), (index + (headerSize - 1)) < self.data.count - 1 { | ||
| var h = try self.parseHeader(bytes: Array(self.data[index...(index + headerSize - 1)])) | ||
|
|
||
| index += headerSize + 1 | ||
| h.contentLocation = index - 1 | ||
| index += h.size | ||
|
|
||
| self.headers.append(h) | ||
| } | ||
| } | ||
|
|
||
| /// Retrieves the bytes of the item at `index`, where index is the index of the `header` stored in the `headers` property of the reader. | ||
| /// | ||
| /// Internally, the `Header` stored at `index` is used to find the file. | ||
| public subscript(index: Int) -> [UInt8] { | ||
| Array(self.data[self.headers[index].contentLocation..<self.headers[index].contentLocation + self.headers[index].size]) | ||
| } | ||
|
|
||
| /// Retrieves the bytes of the file described in `header`. | ||
| /// | ||
| /// - Parameter header: The `Header` that describes the file you wish to retrieves. | ||
| /// | ||
| /// `header` MUST be a `Header` contained in the `headers` property of this `ArArchiveReader` or else you will get a "index out of range" error. | ||
| public subscript(header header: Header) -> [UInt8] { | ||
| Array(self.data[header.contentLocation..<header.contentLocation + header.size]) | ||
| } | ||
|
|
||
| private func parseHeader(bytes: [UInt8]) throws -> Header { | ||
| var start = 0 | ||
| let name = self.readString(from: Array(bytes[start...15])) | ||
|
|
||
| start = 16 | ||
|
|
||
| let modificationTime = self.readInt(from: Array(bytes[start...(start + 11)])) | ||
|
|
||
| start += 12 | ||
| let userID = self.readInt(from: Array(bytes[start...(start + 5)])) | ||
|
|
||
| start += 6 | ||
|
|
||
| let groupID = self.readInt(from: Array(bytes[start...(start + 5)])) | ||
|
|
||
| start += 6 | ||
|
|
||
| let mode = UInt32(String(readString(from: Array(bytes[start...(start + 5)])).dropFirst(3)), radix: 8) | ||
|
|
||
| start += 8 | ||
|
|
||
| let size = self.readInt(from: Array(bytes[start...(start + 7)])) | ||
|
|
||
| guard | ||
| let mT = modificationTime, | ||
| let u = userID, | ||
| let g = groupID, | ||
| let m = mode, | ||
| let s = size | ||
| else { throw ArArchiveError.invalidHeader } | ||
|
|
||
| var h = Header(name: name, userID: u, groupID: g, mode: m, modificationTime: mT) | ||
| h.size = s | ||
| return h | ||
| } | ||
|
|
||
| /// From [blakesmith/r/reader.go: line 62](https://github.com/blakesmith/ar/blob/809d4375e1fb5bb262c159fc3ec2e7a86a8bfd28/reader.go#L62) . | ||
| private func readString(from bytes: [UInt8]) -> String { | ||
| var i = bytes.count - 1 | ||
|
|
||
| while i > 0, bytes[i] == 32 /* ASCII space character */ { | ||
| i -= 1 | ||
| } | ||
|
|
||
| return String(bytes[0...i].map({ Character(Unicode.Scalar($0)) })) | ||
| } | ||
|
|
||
| private func readInt(from bytes: [UInt8], radix: Int? = nil) -> Int? { | ||
| if let r = radix { | ||
| return Int(self.readString(from: bytes), radix: r) | ||
| } else { | ||
| return Int(self.readString(from: bytes)) | ||
| } | ||
| } | ||
| } | ||
|
|
||
| extension ArArchiveReader: IteratorProtocol, Sequence { | ||
| public typealias Element = (Header, [UInt8]) | ||
|
|
||
| public mutating func next() -> Element? { | ||
| if self.currentIndex > self.headers.count - 1 { | ||
| return nil | ||
| } | ||
|
|
||
| let bytes = self[currentIndex] | ||
| let h = self.headers[self.currentIndex] | ||
| self.currentIndex += 1 | ||
|
|
||
| return (h, bytes) | ||
| } | ||
| } |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Oops, something went wrong.