fs/io/File{Reader,OutputStream}: convert path to UTF-8 for error message

src/fs/io/FileOutputStream.cxx

@@ -43,8 +43,11 @@ FileOutputStream::FileOutputStream(Path _path, Error &error)
 			   FILE_ATTRIBUTE_NORMAL|FILE_FLAG_WRITE_THROUGH,
 			   nullptr))
 {
-	if (handle == INVALID_HANDLE_VALUE)
-		error.FormatLastError("Failed to create %s", path.c_str());
+	if (handle == INVALID_HANDLE_VALUE) {
+		const auto path_utf8 = path.ToUTF8();
+		error.FormatLastError("Failed to create %s",
+				      path_utf8.c_str());
+	}
 }
 
 bool
@@ -54,13 +57,17 @@ FileOutputStream::Write(const void *data, size_t size, Error &error)
 
 	DWORD nbytes;
 	if (!WriteFile(handle, data, size, &nbytes, nullptr)) {
-		error.FormatLastError("Failed to write to %s", path.c_str());
+		const auto path_utf8 = path.ToUTF8();
+		error.FormatLastError("Failed to write to %s",
+				      path_utf8.c_str());
 		return false;
 	}
 
 	if (size_t(nbytes) != size) {
+		const auto path_utf8 = path.ToUTF8();
 		error.FormatLastError(ERROR_DISK_FULL,
-				      "Failed to write to %s", path.c_str());
+				      "Failed to write to %s",
+				      path_utf8.c_str());
 		return false;
 	}
 

src/fs/io/FileReader.cxx

@@ -30,8 +30,10 @@ FileReader::FileReader(Path _path, Error &error)
 			   nullptr, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL,
 			   nullptr))
 {
-	if (handle == INVALID_HANDLE_VALUE)
-		error.FormatLastError("Failed to open %s", path.c_str());
+	if (handle == INVALID_HANDLE_VALUE) {
+		const auto path_utf8 = path.ToUTF8();
+		error.FormatLastError("Failed to open %s", path_utf8.c_str());
+	}
 }
 
 size_t
@@ -41,7 +43,9 @@ FileReader::Read(void *data, size_t size, Error &error)
 
 	DWORD nbytes;
 	if (!ReadFile(handle, data, size, &nbytes, nullptr)) {
-		error.FormatLastError("Failed to read from %s", path.c_str());
+		const auto path_utf8 = path.ToUTF8();
+		error.FormatLastError("Failed to read from %s",
+				      path_utf8.c_str());
 		nbytes = 0;
 	}