Merge "Revert "Remove device-side printflags source"" into main

    preinstalled-packages-asl-files.xml \

    preinstalled-packages-platform.xml \

    preinstalled-packages-strict-signature.xml \

    printflags \

    privapp-permissions-platform.xml \

    prng_seeder \

    recovery-persist \

        "preinstalled-packages-platform.xml", // base_system

        "preinstalled-packages-strict-signature.xml", // base_system

        "preloaded-classes", // ok

        "printflags", // base_system

        "privapp-permissions-platform.xml", // base_system

        "prng_seeder", // base_system

        "public.libraries.android.txt",

package {

    default_applicable_licenses: ["Android-Apache-2.0"],

}

rust_defaults {

    name: "printflags.defaults",

    edition: "2021",

    clippy_lints: "android",

    lints: "android",

    srcs: ["src/main.rs"],

    rustlibs: [

        "libaconfig_protos",

        "libanyhow",

        "libprotobuf",

        "libregex",

    ],

}

rust_binary {

    name: "printflags",

    defaults: ["printflags.defaults"],

    apex_available: [

        "//apex_available:platform",

    ],

}

rust_test_host {

    name: "printflags.test",

    defaults: ["printflags.defaults"],

    test_suites: ["general-tests"],

}

[package]

name = "printflags"

version = "0.1.0"

edition = "2021"

[features]

default = ["cargo"]

cargo = []

[dependencies]

anyhow = "1.0.69"

paste = "1.0.11"

protobuf = "3.2.0"

regex = "1.10.3"

aconfig_protos = { path = "../aconfig_protos" }

/*

 * Copyright (C) 2023 The Android Open Source Project

 *

 * Licensed under the Apache License, Version 2.0 (the "License");

 * you may not use this file except in compliance with the License.

 * You may obtain a copy of the License at

 *

 *      http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

 */

//! `printflags` is a device binary to print feature flags.

use aconfig_protos::ProtoFlagState as State;

use aconfig_protos::ProtoParsedFlags;

use anyhow::{bail, Context, Result};

use regex::Regex;

use std::collections::BTreeMap;

use std::collections::HashMap;

use std::process::Command;

use std::{fs, str};

fn parse_device_config(raw: &str) -> HashMap<String, String> {

    let mut flags = HashMap::new();

    let regex = Regex::new(r"(?m)^([[[:alnum:]]_]+/[[[:alnum:]]_\.]+)=(true|false)$").unwrap();

    for capture in regex.captures_iter(raw) {

        let key = capture.get(1).unwrap().as_str().to_string();

        let value = match capture.get(2).unwrap().as_str() {

            "true" => format!("{:?} (device_config)", State::ENABLED),

            "false" => format!("{:?} (device_config)", State::DISABLED),

            _ => panic!(),

        };

        flags.insert(key, value);

    }

    flags

}

fn xxd(bytes: &[u8]) -> String {

    let n = 8.min(bytes.len());

    let mut v = Vec::with_capacity(n);

    for byte in bytes.iter().take(n) {

        v.push(format!("{:02x}", byte));

    }

    let trailer = match bytes.len() {

        0..=8 => "",

        _ => " ..",

    };

    format!("[{}{}]", v.join(" "), trailer)

}

fn main() -> Result<()> {

    // read device_config

    let output = Command::new("/system/bin/device_config").arg("list").output()?;

    if !output.status.success() {

        let reason = match output.status.code() {

            Some(code) => format!("exit code {}", code),

            None => "terminated by signal".to_string(),

        };

        bail!("failed to execute device_config: {}", reason);

    }

    let dc_stdout = str::from_utf8(&output.stdout)?;

    let device_config_flags = parse_device_config(dc_stdout);

    // read aconfig_flags.pb files

    let apex_pattern = Regex::new(r"^/apex/[^@]+\.[^@]+$").unwrap();

    let mut mount_points = vec![

        "system".to_string(),

        "system_ext".to_string(),

        "product".to_string(),

        "vendor".to_string(),

    ];

    for apex in fs::read_dir("/apex")? {

        let path_name = apex?.path().display().to_string();

        if let Some(canonical_path) = apex_pattern.captures(&path_name) {

            mount_points.push(canonical_path.get(0).unwrap().as_str().to_owned());

        }

    }

    let mut flags: BTreeMap<String, Vec<String>> = BTreeMap::new();

    for mount_point in mount_points {

        let path = format!("/{}/etc/aconfig_flags.pb", mount_point);

        let Ok(bytes) = fs::read(&path) else {

            eprintln!("warning: failed to read {}", path);

            continue;

        };

        let parsed_flags: ProtoParsedFlags = protobuf::Message::parse_from_bytes(&bytes)

            .with_context(|| {

                format!("failed to parse {} ({}, {} byte(s))", path, xxd(&bytes), bytes.len())

            })?;

        for flag in parsed_flags.parsed_flag {

            let key = format!("{}/{}.{}", flag.namespace(), flag.package(), flag.name());

            let value = format!("{:?} + {:?} ({})", flag.permission(), flag.state(), mount_point);

            flags.entry(key).or_default().push(value);

        }

    }

    // print flags

    for (key, mut value) in flags {

        if let Some(dc_value) = device_config_flags.get(&key) {

            value.push(dc_value.to_string());

        }

        println!("{}: {}", key, value.join(", "));

    }

    Ok(())

}

#[cfg(test)]

mod tests {

    use super::*;

    #[test]

    fn test_parse_device_config() {

        let input = r#"

namespace_one/com.foo.bar.flag_one=true

namespace_one/com.foo.bar.flag_two=false

random_noise;

namespace_two/android.flag_one=true

namespace_two/android.flag_two=nonsense

"#;

        let expected = HashMap::from([

            (

                "namespace_one/com.foo.bar.flag_one".to_string(),

                "ENABLED (device_config)".to_string(),

            ),

            (

                "namespace_one/com.foo.bar.flag_two".to_string(),

                "DISABLED (device_config)".to_string(),

            ),

            ("namespace_two/android.flag_one".to_string(), "ENABLED (device_config)".to_string()),

        ]);

        let actual = parse_device_config(input);

        assert_eq!(expected, actual);

    }

    #[test]

    fn test_xxd() {

        let input = [0x0, 0x1, 0x2, 0x3, 0x4, 0x5, 0x6, 0x7, 0x8, 0x9];

        assert_eq!("[]", &xxd(&input[0..0]));

        assert_eq!("[00]", &xxd(&input[0..1]));

        assert_eq!("[00 01]", &xxd(&input[0..2]));

        assert_eq!("[00 01 02 03 04 05 06]", &xxd(&input[0..7]));

        assert_eq!("[00 01 02 03 04 05 06 07]", &xxd(&input[0..8]));

        assert_eq!("[00 01 02 03 04 05 06 07 ..]", &xxd(&input[0..9]));

        assert_eq!("[00 01 02 03 04 05 06 07 ..]", &xxd(&input));

    }

}