Fix a potential crash

If the read system call returned an error, we would crash (negative number of read bytes).

Also fix compilation on Windows, but not really (only if fileDescriptor were available on FileHandle on Windows…).

Author: Frizlab

Tests/JSONLoggerTests/Helpers/FileHandleHelper.swift

@@ -35,12 +35,17 @@ extension FileHandle {
 			let buffer = UnsafeMutableRawBufferPointer.allocate(byteCount: 512, alignment: MemoryLayout<UInt8>.alignment)
 			defer {buffer.deallocate()}
 
+#if !os(Windows)
 			var nread = 0
+			let bufferCount = buffer.count
+#else
+			var nread = Int32(0)
+			let bufferCount = UInt32(buffer.count)
+#endif
 			var ret = Data()
-			repeat {
-				nread = system_read(fileDescriptor, buffer.baseAddress, buffer.count)
-				ret += buffer[0..<nread]
-			} while nread > 0
+			while ({ nread = system_read(fileDescriptor, buffer.baseAddress, bufferCount); return nread }()) > 0 {
+				ret += buffer[0..<Int(nread)]
+			}
 			guard nread >= 0 else {
 				throw Errno()
 			}
@@ -50,12 +55,17 @@ extension FileHandle {
 			let buffer = UnsafeMutableRawBufferPointer.allocate(byteCount: 512, alignment: MemoryLayout<UInt8>.alignment)
 			defer {buffer.deallocate()}
 
+#if !os(Windows)
 			var nread = 0
+			let bufferCount = buffer.count
+#else
+			var nread = Int32(0)
+			let bufferCount = UInt32(buffer.count)
+#endif
 			var ret = Data()
-			repeat {
-				nread = system_read(fileDescriptor, buffer.baseAddress, buffer.count)
-				ret += buffer[0..<nread]
-			} while nread > 0
+			while ({ nread = system_read(fileDescriptor, buffer.baseAddress, bufferCount); return nread }()) > 0 {
+				ret += buffer[0..<Int(nread)]
+			}
 			guard nread >= 0 else {
 				throw Errno()
 			}