Testing

test_ext4_server is a utility component that can be used for testing of the Ext4 library.

Note that this test server exposes an ext4 filesystem with full read functionality but limited write support and any changes to metadata are not persisted. Only truncating files to zero and overwriting file contents are supported. Other operations will fail with a “not supported” error.

An ext4 image must be provided to the server. On startup, the server reads an Ext4 filesystem image from its package data directory (/pkg/data/ext4_image.img).

Usage

To use this component in a test, use the ext4_test_server GN template provided in test_ext4_server.gni.

import("//src/storage/ext4/testing/test_ext4_server.gni")

ext4_test_server("ext4_test_pkg") {
  image = "path/to/my_image.img"
}

This template will:

1. Include the my_image.img as a resource in the package, mapped to data/ext4_image.img.
2. Create a fuchsia_package containing the server and the image.

Component Manifest Integration

To use the server in your test, include the provided manifest shard in your test's component manifest. This shard automatically adds the server as a child and mounts its root directory to /test_ext4_filesystem_root.

In my_test.cml:

{
    include: [
        "//src/storage/ext4/testing/meta/server.shard.cml",
    ],
    ...
}