Zip: Add zip file reader

Signed-off-by: Roopesh Chander <roop@roopc.net>
2018-10-29 01:04:46 +05:30
parent 38b816ba4c
commit de3dde84fd
2 changed files with 84 additions and 0 deletions
@@ -0,0 +1,78 @@
+// SPDX-License-Identifier: MIT
+// Copyright © 2018 WireGuard LLC. All rights reserved.
+
+import Foundation
+
+enum ZipArchiveError: Error {
+    case cantOpenInputZipFile
+    case badArchive
+}
+
+class ZipArchive {
+
+    static func unarchive(url: URL, requiredFileExtensions: [String]) throws -> [(fileName: String, contents: Data)] {
+
+        var results: [(fileName: String, contents: Data)] = []
+
+        guard let zipFile = unzOpen64(url.path) else {
+            throw ZipArchiveError.cantOpenInputZipFile
+        }
+        defer {
+            unzClose(zipFile)
+        }
+        guard (unzGoToFirstFile(zipFile) == UNZ_OK) else {
+            throw ZipArchiveError.badArchive
+        }
+
+        var resultOfGoToNextFile: Int32
+        repeat {
+            guard (unzOpenCurrentFile(zipFile) == UNZ_OK) else {
+                throw ZipArchiveError.badArchive
+            }
+
+            let bufferSize = 1024
+            var fileNameBuffer = UnsafeMutablePointer<Int8>.allocate(capacity: bufferSize)
+            var dataBuffer = UnsafeMutablePointer<Int8>.allocate(capacity: bufferSize)
+
+            defer {
+                fileNameBuffer.deallocate()
+                dataBuffer.deallocate()
+            }
+
+            guard (unzGetCurrentFileInfo64(zipFile, nil, fileNameBuffer, UInt(bufferSize), nil, 0, nil, 0) == UNZ_OK) else {
+                throw ZipArchiveError.badArchive
+            }
+
+            let fileName = String(cString: fileNameBuffer)
+            let fileExtension = URL(string: fileName)?.pathExtension ?? ""
+
+            if (requiredFileExtensions.contains(fileExtension)) {
+                var unzippedData = Data()
+                var bytesRead: Int32 = 0
+                repeat {
+                    bytesRead = unzReadCurrentFile(zipFile, dataBuffer, UInt32(bufferSize))
+                    if (bytesRead > 0) {
+                        let dataRead = dataBuffer.withMemoryRebound(to: UInt8.self, capacity: bufferSize) {
+                            (buf: UnsafeMutablePointer<UInt8>) -> Data in
+                            return Data(bytes: buf, count: Int(bytesRead))
+                        }
+                        unzippedData.append(dataRead)
+                    }
+                } while (bytesRead > 0)
+                results.append((fileName: fileName, contents: unzippedData))
+            }
+
+            guard (unzCloseCurrentFile(zipFile) == UNZ_OK) else {
+                throw ZipArchiveError.badArchive
+            }
+
+            resultOfGoToNextFile = unzGoToNextFile(zipFile)
+        } while (resultOfGoToNextFile == UNZ_OK)
+
+        if (resultOfGoToNextFile == UNZ_END_OF_LIST_OF_FILE) {
+            return results
+        } else {
+            throw ZipArchiveError.badArchive
+        }
+    }
+}