prevent sigsev when mapping FileInfo on windows

cryptomator · Oct 19, 2023 · 63281af · 63281af
1 parent d725a32
commit 63281af
Show file tree

Hide file tree

Showing 2 changed files with 18 additions and 5 deletions.
diff --git a/jfuse-win/src/main/java/org/cryptomator/jfuse/win/FileInfoImpl.java b/jfuse-win/src/main/java/org/cryptomator/jfuse/win/FileInfoImpl.java
@@ -3,6 +3,7 @@
 import org.cryptomator.jfuse.api.FileInfo;
 import org.cryptomator.jfuse.win.extr.fcntl.fcntl_h;
 import org.cryptomator.jfuse.win.extr.fuse3.fuse3_file_info;
+import org.jetbrains.annotations.Nullable;
 
 import java.lang.foreign.Arena;
 import java.lang.foreign.MemorySegment;
@@ -20,6 +21,18 @@ record FileInfoImpl(MemorySegment segment) implements FileInfo {
 	private static final int O_TRUNC = fcntl_h.O_TRUNC();
 	private static final int O_EXCL = fcntl_h.O_EXCL();
 
+	/**
+	 * Factory method to map native memory to an {@link FileInfo} object
+	 *
+	 * @param address the {@link MemorySegment} representing the starting address
+	 * @param scope   the {@link Arena} in which this object will be alive
+	 * @return an {@link FileInfo} object or {@code null} if {@code address} is a NULL pointer
+	 */
+	@Nullable
+	public static FileInfoImpl of(MemorySegment address, Arena scope) {
+		return MemorySegment.NULL.equals(address) ? null : new FileInfoImpl(address, scope);
+	}
+
 	public FileInfoImpl(MemorySegment address, Arena scope) {
 		this(fuse3_file_info.ofAddress(address, scope));
 	}

diff --git a/jfuse-win/src/main/java/org/cryptomator/jfuse/win/FuseImpl.java b/jfuse-win/src/main/java/org/cryptomator/jfuse/win/FuseImpl.java
@@ -126,14 +126,14 @@ MemorySegment init(MemorySegment conn, MemorySegment cfg) {
 
 	private int chmod(MemorySegment path, int mode, MemorySegment fi) {
 		try (var arena = Arena.ofConfined()) {
-			return fuseOperations.chmod(path.getUtf8String(0), mode, new FileInfoImpl(fi, arena));
+			return fuseOperations.chmod(path.getUtf8String(0), mode, FileInfoImpl.of(fi, arena));
 		}
 	}
 
 	@VisibleForTesting
 	int chown(MemorySegment path, int uid, int gid, MemorySegment fi) {
 		try (var arena = Arena.ofConfined()) {
-			return fuseOperations.chown(path.getUtf8String(0), uid, gid, new FileInfoImpl(fi, arena));
+			return fuseOperations.chown(path.getUtf8String(0), uid, gid, FileInfoImpl.of(fi, arena));
 		}
 	}
 
@@ -171,7 +171,7 @@ int fsyncdir(MemorySegment path, int datasync, MemorySegment fi) {
 	@VisibleForTesting
 	int getattr(MemorySegment path, MemorySegment stat, MemorySegment fi) {
 		try (var arena = Arena.ofConfined()) {
-			return fuseOperations.getattr(path.getUtf8String(0), new StatImpl(stat, arena), new FileInfoImpl(fi, arena));
+			return fuseOperations.getattr(path.getUtf8String(0), new StatImpl(stat, arena), FileInfoImpl.of(fi, arena));
 		}
 	}
 
@@ -265,7 +265,7 @@ private int symlink(MemorySegment linkname, MemorySegment target) {
 	@VisibleForTesting
 	int truncate(MemorySegment path, long size, MemorySegment fi) {
 		try (var arena = Arena.ofConfined()) {
-			return fuseOperations.truncate(path.getUtf8String(0), size, new FileInfoImpl(fi, arena));
+			return fuseOperations.truncate(path.getUtf8String(0), size, FileInfoImpl.of(fi, arena));
 		}
 	}
 
@@ -282,7 +282,7 @@ int utimens(MemorySegment path, MemorySegment times, MemorySegment fi) {
 			var segment = times.reinterpret(seq.byteSize());
 			var time0 = segment.asSlice(0, fuse_timespec.$LAYOUT().byteSize());
 			var time1 = segment.asSlice(fuse_timespec.$LAYOUT().byteSize(), fuse_timespec.$LAYOUT().byteSize());
-			return fuseOperations.utimens(path.getUtf8String(0), new TimeSpecImpl(time0), new TimeSpecImpl(time1), new FileInfoImpl(fi, arena));
+			return fuseOperations.utimens(path.getUtf8String(0), new TimeSpecImpl(time0), new TimeSpecImpl(time1), FileInfoImpl.of(fi, arena));
 		}
 	}