Restructured the source code in the Playdate bindings target.

Sources/PlaydateKit/File/Classes/Handle.swift

@@ -0,0 +1,103 @@
+internal import CPlaydate
+
+extension File {
+    /// An open file. Wraps `SDFile`. The file is closed on deinit if it has
+    /// not been closed explicitly.
+    public final class Handle {
+        let pointer: UnsafeMutableRawPointer
+        private var isClosed = false
+
+        /// Opens the file at `path`.
+        public init(path: String, mode: Options) throws(PlaydateError) {
+            let pointer = path.withPlaydateCString {
+                fileAPI.pointee.open.unsafelyUnwrapped($0, mode.cValue)
+            }
+            guard let pointer else { throw lastFileError() }
+            self.pointer = pointer
+        }
+
+        deinit {
+            if !isClosed {
+                _ = fileAPI.pointee.close.unsafelyUnwrapped(pointer)
+            }
+        }
+
+        /// Closes the file. Further operations are invalid.
+        public func close() throws(PlaydateError) {
+            guard !isClosed else { return }
+            isClosed = true
+            if fileAPI.pointee.close.unsafelyUnwrapped(pointer) != 0 { throw lastFileError() }
+        }
+
+        /// Reads up to `buffer.count` bytes into `buffer`. Returns the number
+        /// of bytes read; 0 indicates end of file.
+        public func read(into buffer: UnsafeMutableRawBufferPointer) throws(PlaydateError) -> Int {
+            let result = fileAPI.pointee.read.unsafelyUnwrapped(
+                pointer, buffer.baseAddress, UInt32(buffer.count))
+            if result < 0 { throw lastFileError() }
+            return Int(result)
+        }
+
+        /// Reads up to `length` bytes and returns them.
+        public func read(length: Int) throws(PlaydateError) -> [UInt8] {
+            var bytes = [UInt8](repeating: 0, count: length)
+            let result = bytes.withUnsafeMutableBytes { buffer in
+                fileAPI.pointee.read.unsafelyUnwrapped(pointer, buffer.baseAddress, UInt32(buffer.count))
+            }
+            if result < 0 { throw lastFileError() }
+            bytes.removeLast(length - Int(result))
+            return bytes
+        }
+
+        /// Writes the buffer to the file. Returns the number of bytes written.
+        @discardableResult
+        public func write(_ buffer: UnsafeRawBufferPointer) throws(PlaydateError) -> Int {
+            let result = fileAPI.pointee.write.unsafelyUnwrapped(
+                pointer, buffer.baseAddress, UInt32(buffer.count))
+            if result < 0 { throw lastFileError() }
+            return Int(result)
+        }
+
+        /// Writes the bytes to the file. Returns the number of bytes written.
+        @discardableResult
+        public func write(_ bytes: [UInt8]) throws(PlaydateError) -> Int {
+            let result = bytes.withUnsafeBytes { buffer in
+                fileAPI.pointee.write.unsafelyUnwrapped(pointer, buffer.baseAddress, UInt32(buffer.count))
+            }
+            if result < 0 { throw lastFileError() }
+            return Int(result)
+        }
+
+        /// Writes the string's UTF-8 to the file. Returns the bytes written.
+        @discardableResult
+        public func write(_ string: String) throws(PlaydateError) -> Int {
+            let result = string.withPlaydateUTF8 { bytes, count in
+                fileAPI.pointee.write.unsafelyUnwrapped(pointer, bytes, UInt32(count))
+            }
+            if result < 0 { throw lastFileError() }
+            return Int(result)
+        }
+
+        /// Flushes buffered writes to disk. Returns the bytes written.
+        @discardableResult
+        public func flush() throws(PlaydateError) -> Int {
+            let result = fileAPI.pointee.flush.unsafelyUnwrapped(pointer)
+            if result < 0 { throw lastFileError() }
+            return Int(result)
+        }
+
+        /// The current read/write offset.
+        public func tell() throws(PlaydateError) -> Int {
+            let result = fileAPI.pointee.tell.unsafelyUnwrapped(pointer)
+            if result < 0 { throw lastFileError() }
+            return Int(result)
+        }
+
+        /// Moves the read/write offset to `offset` relative to `origin`.
+        public func seek(to offset: Int, from origin: SeekOrigin = .start) throws(PlaydateError) {
+            if fileAPI.pointee.seek.unsafelyUnwrapped(pointer, Int32(offset), origin.rawValue) != 0 {
+                throw lastFileError()
+            }
+        }
+    }
+}