replace println! with trace!

until now groups had members without useraccount after the account has been deleted.

fixes: #5

.github/workflows/rust.yml

@@ -0,0 +1,45 @@
+name: Rust
+
+on:
+  push:
+    branches: [ master ]
+  pull_request:
+    branches: [ master ]
+
+env:
+  CARGO_TERM_COLOR: always
+
+jobs:
+  build:
+
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v2
+    - name: Install latest nightly
+      uses: actions-rs/toolchain@v1
+      with:
+          toolchain: nightly
+          override: true
+          components: rustfmt, clippy
+
+    # `cargo check` command here will use installed `nightly`
+    # as it is set as an "override" for current directory
+
+    - name: Run cargo check
+      uses: actions-rs/cargo@v1
+      with:
+        command: check
+    - name: Annotate commit with clippy warnings
+      uses: actions-rs/clippy-check@v1
+      with:
+        token: ${{ secrets.GITHUB_TOKEN }}
+        args: --all-features -- -Wclippy::all -Wclippy::pedantic -Wclippy::nursery -Wclippy::cargo -Aclippy::non_ascii_literal -Aclippy::missing_errors_doc -Aclippy::multiple_crate_versions
+    - name: Run cargo Build
+      uses: actions-rs/cargo@v1
+      with:
+        command: build
+    - name: Run cargo test
+      uses: actions-rs/cargo@v1
+      with:
+        command: test

.gitignore

@@ -1,3 +1,4 @@
 /target
 .vscode
 launch.json
+*.orig

Cargo.lock

@@ -1,5 +1,575 @@
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+checksum = "ac3b87c63620426dd9b991e5ce0329eff545bccbbb34f3be09ff6fb6ab51b7b6"
+
+[[package]]
+name = "winapi-util"
+version = "0.1.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "70ec6ce85bb158151cae5e5c87f95a8e97d2c0c4b001223f33a334e3ce5de178"
+dependencies = [
+ "winapi",
+]
+
+[[package]]
+name = "winapi-x86_64-pc-windows-gnu"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "712e227841d057c1ee1cd2fb22fa7e5a5461ae8e48fa2ca79ec42cfc1931183f"

Cargo.toml

@@ -1,9 +1,33 @@
 [package]
-name = "adduser"
+name = "umanux"
-version = "0.1.0"
+version = "0.1.1"
+description = "Library for managing Linux users and their directories"
 authors = ["Dietrich <dietrich@teilgedanken.de>"]
 edition = "2018"
+license = "MIT OR Apache-2.0"
+keywords = ["user", "admin", "linux", "manage", "passwd"]
+categories = ["os", "os::linux-apis", "parser-implementations", "command-line-utilities"]
+repository = "https://github.com/umanux/umanux"
+readme = "README.md"
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
+regex = "1"
+lazy_static = "1.4"
+log = "0.4"
+simplelog = "0.8"
+chrono = "0.4"
+env_logger = "0.8"
+derive_builder = "0.9"
+clap = "3.0.0-beta"
+
+[dev-dependencies]
+tempfile = "3.1"
+test_bin= "0.3"
+
+
+# optimize for size at cost of compilation speed.
+[profile.release]
+lto = true
+codegen-units = 1

LICENSE

@@ -0,0 +1,9 @@
+MIT License
+
+Copyright (c) 2020 Franz Dietrich
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

LICENSE-APACHE

@@ -0,0 +1,201 @@
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
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+      and distribution as defined by Sections 1 through 9 of this document.
+
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+
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+      direction or management of such entity, whether by contract or
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+      outstanding shares, or (iii) beneficial ownership of such entity.
+
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+      for use, reproduction, or distribution of Your modifications, or
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+      reproduction, and distribution of the Work otherwise complies with
+      the conditions stated in this License.
+
+   5. Submission of Contributions. Unless You explicitly state otherwise,
+      any Contribution intentionally submitted for inclusion in the Work
+      by You to the Licensor shall be under the terms and conditions of
+      this License, without any additional terms or conditions.
+      Notwithstanding the above, nothing herein shall supersede or modify
+      the terms of any separate license agreement you may have executed
+      with Licensor regarding such Contributions.
+
+   6. Trademarks. This License does not grant permission to use the trade
+      names, trademarks, service marks, or product names of the Licensor,
+      except as required for reasonable and customary use in describing the
+      origin of the Work and reproducing the content of the NOTICE file.
+
+   7. Disclaimer of Warranty. Unless required by applicable law or
+      agreed to in writing, Licensor provides the Work (and each
+      Contributor provides its Contributions) on an "AS IS" BASIS,
+      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+      implied, including, without limitation, any warranties or conditions
+      of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
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+      appropriateness of using or redistributing the Work and assume any
+      risks associated with Your exercise of permissions under this License.
+
+   8. Limitation of Liability. In no event and under no legal theory,
+      whether in tort (including negligence), contract, or otherwise,
+      unless required by applicable law (such as deliberate and grossly
+      negligent acts) or agreed to in writing, shall any Contributor be
+      liable to You for damages, including any direct, indirect, special,
+      incidental, or consequential damages of any character arising as a
+      result of this License or out of the use or inability to use the
+      Work (including but not limited to damages for loss of goodwill,
+      work stoppage, computer failure or malfunction, or any and all
+      other commercial damages or losses), even if such Contributor
+      has been advised of the possibility of such damages.
+
+   9. Accepting Warranty or Additional Liability. While redistributing
+      the Work or Derivative Works thereof, You may choose to offer,
+      and charge a fee for, acceptance of support, warranty, indemnity,
+      or other liability obligations and/or rights consistent with this
+      License. However, in accepting such obligations, You may act only
+      on Your own behalf and on Your sole responsibility, not on behalf
+      of any other Contributor, and only if You agree to indemnify,
+      defend, and hold each Contributor harmless for any liability
+      incurred by, or claims asserted against, such Contributor by reason
+      of your accepting any such warranty or additional liability.
+
+   END OF TERMS AND CONDITIONS
+
+   APPENDIX: How to apply the Apache License to your work.
+
+      To apply the Apache License to your work, attach the following
+      boilerplate notice, with the fields enclosed by brackets "[]"
+      replaced with your own identifying information. (Don't include
+      the brackets!)  The text should be enclosed in the appropriate
+      comment syntax for the file format. We also recommend that a
+      file or class name and description of purpose be included on the
+      same "printed page" as the copyright notice for easier
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+
+   Copyright 2020 Franz Dietrich
+
+   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.

README.md

@@ -0,0 +1,51 @@
+# **U**ser **MAN**ager for lin**UX**
+### A Usermanager written in Rust
+
+> This project is **very much** work in progress. Do **absolutely not** use in production systems!
+
+When done this library intends to provide all the functionality needed to manage users on a linux system.
+
+What is working so far:
+  * [x] Parsing:
+    * [x] `/etc/passwd`
+    * [x] `/etc/shadow` (root permission needed)
+    * [x] `/etc/group`
+
+  * Modifying:
+    * delete a user
+        * [x] passwd
+        * [x] shadow
+        * [X] group
+            * [x] own primary group
+            * [x] membership in other groups
+        * [x] home dir
+            * [x] delete
+            * [x] keep
+            * [ ] archive
+        * [ ] mail?
+        * [ ] multiple entries "Multiple entries named '%s' in %s. Please fix this with pwck or grpck."
+        * [ ] cancel jobs:
+            * [ ] cron
+            * [ ] at
+            * [ ] print
+    * create a user
+        - [x] passwd
+        - [x] shadow
+        - [ ] group
+            - [ ] own group
+        - [ ] home dir
+            - [ ] create from skeleton
+            - [ ] Skip
+            - [ ] create from directory
+        - [ ] mail?
+        - [ ] multiple entries (check uid duplication)
+
+
+## License
+
+Umanux is licensed under either of the following, at your option:
+
+ * Apache License, Version 2.0, ([LICENSE-APACHE](LICENSE-APACHE) or http://www.apache.org/licenses/LICENSE-2.0)
+ * MIT License ([LICENSE-MIT](LICENSE) or http://opensource.org/licenses/MIT)
+
+`SPDX-License-Identifier: Apache-2.0 OR MIT`

src/api/createuser_args.rs

@@ -0,0 +1,40 @@
+#![allow(clippy::default_trait_access)]
+use std::path::PathBuf;
+
+#[derive(Debug, Clone, Eq, PartialEq)]
+pub enum CreateHome {
+    Create,
+    Skip,
+    HomeFromDir { path: PathBuf },
+}
+#[derive(Debug, Clone, Eq, PartialEq)]
+pub enum CreatePrimaryGroup {
+    Create,
+    Skip,
+    CreateIfEmptyOrAdd,
+}
+#[derive(Debug, Builder, Eq, PartialEq)]
+#[builder(public)]
+#[builder(default)]
+pub struct CreateUserArgs<'a> {
+    pub username: &'a str,
+    pub delete_home: CreateHome,
+    pub delete_primary_group: CreatePrimaryGroup,
+}
+
+impl<'a> CreateUserArgs<'a> {
+    #[must_use]
+    pub fn builder() -> CreateUserArgsBuilder<'a> {
+        CreateUserArgsBuilder::default()
+    }
+}
+
+impl Default for CreateUserArgs<'_> {
+    fn default() -> Self {
+        Self {
+            username: "defaultuser",
+            delete_home: CreateHome::Create,
+            delete_primary_group: CreatePrimaryGroup::CreateIfEmptyOrAdd,
+        }
+    }
+}

src/api/deleteuser_args.rs

@@ -0,0 +1,40 @@
+#![allow(clippy::default_trait_access)]
+use std::path::PathBuf;
+
+#[derive(Debug, Clone, Eq, PartialEq)]
+pub enum DeleteHome {
+    Delete,
+    Keep,
+    Archive { path: PathBuf },
+}
+#[derive(Debug, Clone, Eq, PartialEq)]
+pub enum DeletePrimaryGroup {
+    Delete,
+    Keep,
+    DeleteIfEmpty,
+}
+#[derive(Debug, Builder, Eq, PartialEq)]
+#[builder(public)]
+#[builder(default)]
+pub struct DeleteUserArgs<'a> {
+    pub username: &'a str,
+    pub delete_home: DeleteHome,
+    pub delete_primary_group: DeletePrimaryGroup,
+}
+
+impl<'a> DeleteUserArgs<'a> {
+    #[must_use]
+    pub fn builder() -> DeleteUserArgsBuilder<'a> {
+        DeleteUserArgsBuilder::default()
+    }
+}
+
+impl Default for DeleteUserArgs<'_> {
+    fn default() -> Self {
+        Self {
+            username: "defaultuser",
+            delete_home: DeleteHome::Keep,
+            delete_primary_group: DeletePrimaryGroup::DeleteIfEmpty,
+        }
+    }
+}

src/api/mod.rs

@@ -0,0 +1,72 @@
+pub mod createuser_args;
+pub mod deleteuser_args;
+
+pub use createuser_args::{CreateHome, CreatePrimaryGroup, CreateUserArgs};
+pub use deleteuser_args::{DeleteHome, DeletePrimaryGroup, DeleteUserArgs};
+pub trait UserDBRead {
+    fn get_all_users(&self) -> Vec<&crate::User>;
+    fn get_user_by_name(&self, name: &str) -> Option<&crate::User>;
+    fn get_user_by_id(&self, uid: u32) -> Option<&crate::User>;
+    fn get_all_groups(&self) -> Vec<crate::Group>;
+    fn get_group_by_name(&self, name: &str) -> Option<&crate::Group>;
+    fn get_group_by_id(&self, name: u32) -> Option<&crate::Group>;
+}
+
+pub trait UserDBValidation {
+    fn is_uid_valid_and_free(&self, uid: u32) -> bool;
+    fn is_username_valid_and_free(&self, name: &str) -> bool;
+    fn is_gid_valid_and_free(&self, gid: u32) -> bool;
+    fn is_groupname_valid_and_free(&self, name: &str) -> bool;
+}
+
+pub trait UserDBWrite {
+    fn delete_user(&mut self, params: DeleteUserArgs) -> Result<crate::User, crate::UserLibError>;
+    fn new_user(&mut self, params: CreateUserArgs) -> Result<&crate::User, crate::UserLibError>;
+    fn delete_group(&mut self, group: &crate::Group) -> Result<(), crate::UserLibError>;
+    fn new_group(&mut self) -> Result<&crate::Group, crate::UserLibError>;
+}
+
+pub trait UserRead {
+    fn get_username(&self) -> Option<&str>;
+    fn get_uid(&self) -> u32;
+    fn get_gid(&self) -> u32;
+    fn get_password(&self) -> Option<&str>;
+    fn get_gecos(&self) -> Option<&crate::Gecos>;
+    fn get_home_dir(&self) -> Option<&str>;
+    fn get_shell_path(&self) -> Option<&str>;
+    fn get_full_name(&self) -> Option<&str>;
+    fn get_room(&self) -> Option<&str>;
+    fn get_phone_work(&self) -> Option<&str>;
+    fn get_phone_home(&self) -> Option<&str>;
+    fn get_other(&self) -> Option<&Vec<String>>;
+}
+
+pub trait UserWrite {
+    fn set_username(&self, username: String);
+    fn set_uid(&self, uid: u32);
+    fn set_gid(&self, gid: u32);
+    fn set_password(&self, password: String);
+    fn set_gecos(&self, gecos: crate::Gecos);
+    fn set_home_dir(&self, home_dir: String);
+    fn set_shell_path(&self, shell_path: String);
+    fn set_full_name(&self, full_name: String);
+    fn set_room(&self, room: String);
+    fn set_phone_work(&self, phone_work: String);
+    fn set_phone_home(&self, phone_home: String);
+    fn set_other(&self, other: Option<Vec<String>>);
+}
+
+pub trait GroupRead {
+    fn get_groupname(&self) -> Option<&str>;
+    fn get_encrypted_password(&self) -> Option<&str>;
+    fn get_gid(&self) -> Option<u32>;
+    fn get_member_names(&self) -> Option<Vec<&str>>;
+}
+
+pub trait GroupWrite<T> {
+    fn set_groupname(&self) -> Option<crate::Group>;
+    fn set_password(&self) -> Option<crate::Group>;
+    fn set_gid(&self) -> Option<crate::Group>;
+    fn add_member(user: T) -> Option<crate::Group>;
+    fn remove_member(user: T) -> Option<crate::Group>;
+}

src/bin/create_user.rs

@@ -0,0 +1,69 @@
+use std::path::PathBuf;
+
+extern crate clap;
+use clap::{App, Arg};
+
+extern crate umanux;
+use umanux::{api::UserDBWrite, UserLibError};
+
+fn main() -> Result<(), UserLibError> {
+    env_logger::init();
+    let matches = App::new("Create a new linux user")
+        .version("0.1.0")
+        .author("Franz Dietrich <dietrich@teilgedanken.de>")
+        .about("Create a linux user do not use this in production (yet)")
+        .arg(
+            Arg::new("username")
+                .value_name("USERNAME")
+                .about("the new users name")
+                .takes_value(true)
+                .required(true),
+        )
+        .arg(
+            Arg::new("passwd")
+                .short('p')
+                .long("passwd")
+                .value_name("FILE")
+                .about("The passwd file")
+                .default_value("/etc/passwd")
+                .takes_value(true),
+        )
+        .arg(
+            Arg::new("shadow")
+                .short('s')
+                .long("shadow")
+                .value_name("FILE")
+                .about("The shadow file")
+                .default_value("/etc/shadow")
+                .takes_value(true),
+        )
+        .arg(
+            Arg::new("group")
+                .short('g')
+                .long("group")
+                .value_name("FILE")
+                .about("The group file")
+                .default_value("/etc/group")
+                .takes_value(true),
+        )
+        .get_matches();
+
+    let mf = umanux::Files {
+        passwd: Some(PathBuf::from(matches.value_of("passwd").unwrap())),
+        shadow: Some(PathBuf::from(matches.value_of("shadow").unwrap())),
+        group: Some(PathBuf::from(matches.value_of("group").unwrap())),
+    };
+
+    let mut db = umanux::UserDBLocal::load_files(mf).unwrap();
+
+    match db.new_user(
+        umanux::api::CreateUserArgs::builder()
+            .username(matches.value_of("username").unwrap())
+            // .delete_home(umanux::api::DeleteHome::Delete)
+            .build()
+            .unwrap(),
+    ) {
+        Ok(_) => Ok(()),
+        Err(e) => Err(e),
+    }
+}

src/bin/delete_user.rs

@@ -0,0 +1,37 @@
+use std::path::PathBuf;
+
+extern crate umanux;
+
+use umanux::api::UserDBWrite;
+use umanux::api::UserRead;
+
+extern crate env_logger;
+#[allow(unused_imports)]
+use log::{debug, error, info, trace, warn};
+
+fn main() {
+    env_logger::init();
+
+    let mf = umanux::Files {
+        passwd: Some(PathBuf::from("./passwd")),
+        shadow: Some(PathBuf::from("./shadow")),
+        group: Some(PathBuf::from("./group")),
+    };
+
+    let mut db = umanux::UserDBLocal::load_files(mf).unwrap();
+
+    let user_res: Result<umanux::User, umanux::UserLibError> = db.delete_user(
+        umanux::api::DeleteUserArgs::builder()
+            .username("teste")
+            // .delete_home(umanux::api::DeleteHome::Delete)
+            .build()
+            .unwrap(),
+    );
+    match user_res {
+        Ok(u) => info!(
+            "The user <{}> has been deleted! ",
+            u.get_username().unwrap()
+        ),
+        Err(e) => error!("Failed to delete the user: {}", e),
+    }
+}

src/bin/main.rs

@@ -1,21 +0,0 @@
-extern crate adduser;
-
-use adduser::passwd::Passwd;
-use std::fs::File;
-use std::io::{prelude::*, BufReader};
-
-fn main() {
-    let file = File::open("/etc/passwd").unwrap();
-    let reader = BufReader::new(file);
-
-    for line in reader.lines() {
-        println!("{}", Passwd::new_from_string(&line.unwrap()).unwrap());
-    }
-
-    // let pwd = Passwd::default();
-    // let pwd2 =
-    //     Passwd::new_from_string("howdy:notencrypted:1001:1001:not done:/home/test:/bin/bash");
-    // println!("Test struct: {}", pwd);
-
-    // assert_eq!(pwd, pwd2.unwrap())
-}

src/bin/read_all.rs

@@ -0,0 +1,36 @@
+extern crate umanux;
+use umanux::api::GroupRead;
+use umanux::api::UserDBRead;
+
+fn main() {
+    simplelog::CombinedLogger::init(vec![simplelog::TermLogger::new(
+        simplelog::LevelFilter::Warn,
+        simplelog::Config::default(),
+        simplelog::TerminalMode::Mixed,
+    )])
+    .unwrap();
+
+    let db = umanux::UserDBLocal::load_files(umanux::Files::default()).unwrap();
+
+    for u in db.get_all_users() {
+        println!("{}", u);
+        println!(
+            "Groups: {:?}",
+            u.get_groups()
+                .iter()
+                .map(|group| {
+                    (
+                        format!("{:?}", group.0),
+                        group.1.borrow().get_groupname().unwrap().to_owned(),
+                    )
+                })
+                .collect::<Vec<(String, String)>>()
+        );
+    }
+
+    for group in db.get_all_groups() {
+        let gp = group.borrow();
+        println!("{}", gp);
+        println!("{:?}", gp.get_member_names())
+    }
+}

src/error.rs

@@ -0,0 +1,106 @@
+use std::error::Error;
+use std::fmt::{self, Display};
+
+#[allow(clippy::module_name_repetitions)]
+#[derive(Debug, PartialEq)]
+pub enum ParseError {
+    Username,
+    Password,
+    Uid,
+    Gid,
+    Gecos,
+    HomeDir,
+    ShellDir,
+}
+
+#[allow(clippy::module_name_repetitions)]
+#[derive(Debug, PartialEq)]
+pub enum UserLibError {
+    NotFound,
+    ParseError,
+    FilesChanged,
+    FilesRequired,
+    Message(MyMessage),
+}
+
+#[derive(Debug)]
+pub enum MyMessage {
+    Simple(String),
+    IOError(String, std::io::Error),
+}
+
+impl PartialEq for MyMessage {
+    fn eq(&self, other: &Self) -> bool {
+        format!("{}", self).eq(&format!("{}", other))
+    }
+}
+
+impl Display for MyMessage {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        match self {
+            Self::Simple(m) => write!(f, "{}", m),
+            Self::IOError(m, e) => write!(f, "{},{}", m, e),
+        }
+    }
+}
+
+impl Display for UserLibError {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        match self {
+            Self::NotFound => write!(f, "not found"),
+            Self::ParseError => write!(f, "failed to parse"),
+            Self::FilesRequired => write!(
+                f,
+                "File locking is only possible if some files are specified"
+            ),
+            Self::FilesChanged => write!(
+                f,
+                "The files changed. Updating could lead to conflict aborting."
+            ),
+            Self::Message(message) => write!(f, "{}", message),
+        }
+    }
+}
+
+impl Error for UserLibError {
+    fn source(&self) -> Option<&(dyn Error + 'static)> {
+        match *self {
+            Self::NotFound
+            | Self::ParseError
+            | Self::FilesChanged
+            | Self::FilesRequired
+            | Self::Message(MyMessage::Simple(_)) => None,
+            Self::Message(MyMessage::IOError(_, ref e)) => Some(e),
+        }
+    }
+}
+
+impl From<&str> for UserLibError {
+    fn from(err: &str) -> Self {
+        Self::Message(MyMessage::Simple(err.to_owned()))
+    }
+}
+
+impl From<String> for UserLibError {
+    fn from(err: String) -> Self {
+        Self::Message(MyMessage::Simple(err))
+    }
+}
+
+impl From<std::io::Error> for UserLibError {
+    fn from(e: std::io::Error) -> Self {
+        Self::Message(MyMessage::Simple(e.to_string()))
+    }
+}
+
+impl From<(String, std::io::Error)> for UserLibError {
+    fn from((m, e): (String, std::io::Error)) -> Self {
+        Self::Message(MyMessage::IOError(m, e))
+    }
+}
+/*
+impl From<(String, Error)> for UserLibError {
+    fn from((m, e): (String, Error)) -> Self {
+        UserLibError::Message(MyMessage::IOError(m, e))
+    }
+}*/

src/group/mod.rs

@@ -0,0 +1,208 @@
+#![allow(clippy::non_ascii_literal)]
+
+use crate::userlib::NewFromString;
+use log::warn;
+
+use crate::UserLibError;
+use std::fmt::{self, Debug, Display};
+use std::{cell::RefCell, convert::TryFrom};
+use std::{cmp::Eq, rc::Rc};
+
+#[derive(Debug, PartialEq, Eq, Clone, Copy)]
+pub enum MembershipKind {
+    Primary,
+    Member,
+}
+
+#[derive(Debug, PartialEq, Eq, Clone)]
+pub struct Membership {
+    kind: MembershipKind,
+    username: crate::Username,
+}
+
+#[derive(Debug, PartialEq, Eq)]
+pub struct Groupname {
+    groupname: String,
+}
+
+impl Display for Groupname {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "{}", self.groupname,)
+    }
+}
+
+impl TryFrom<String> for Groupname {
+    type Error = UserLibError;
+    fn try_from(source: String) -> std::result::Result<Self, Self::Error> {
+        if is_groupname_valid(&source) {
+            Ok(Self { groupname: source })
+        } else if source == "Debian-exim" {
+            warn!("username {} is not a valid username. This might cause problems. (It is default in Debian and Ubuntu)", source);
+            Ok(Self { groupname: source })
+        } else {
+            Err(format!("Invalid groupname -{}-", source).into())
+        }
+    }
+}
+
+pub(crate) fn is_groupname_valid(name: &str) -> bool {
+    // for now just use the username validation.
+    crate::user::passwd_fields::is_username_valid(name)
+}
+
+pub type Group = Rc<RefCell<Inner>>;
+/// A record(line) in the user database `/etc/shadow` found in most linux systems.
+#[derive(Debug, PartialEq, Eq)]
+pub struct Inner {
+    pos: u32,
+    source: String,
+    groupname: Groupname,                 /* Username.  */
+    pub(crate) password: crate::Password, /* Usually not used (disabled with x) */
+    gid: crate::Gid,                      /* Group ID.  */
+    members: Vec<Membership>,             /* Real name.  */
+}
+
+impl Inner {
+    #[must_use]
+    pub fn remove_in(&self, content: &str) -> String {
+        content
+            .split(&self.source)
+            .map(str::trim)
+            .collect::<Vec<&str>>()
+            .join("\n")
+    }
+
+    pub(super) fn append_user(&mut self, username: &str) {
+        self.members.push(Membership {
+            kind: MembershipKind::Primary,
+            username: crate::Username {
+                username: username.to_owned(),
+            },
+        })
+    }
+
+    pub(super) fn remove_member(&mut self, kind: MembershipKind, username: &str) {
+        self.members
+            .retain(|u| !(u.username.username == username && u.kind == kind))
+    }
+}
+
+use crate::api::GroupRead;
+impl GroupRead for Inner {
+    #[must_use]
+    fn get_groupname(&self) -> Option<&str> {
+        Some(&self.groupname.groupname)
+    }
+    #[must_use]
+    fn get_member_names(&self) -> Option<Vec<&str>> {
+        let mut r: Vec<&str> = Vec::new();
+        for u in &self.members {
+            r.push(&u.username.username);
+        }
+        Some(r)
+    }
+
+    fn get_gid(&self) -> Option<u32> {
+        Some(self.gid.get_gid())
+    }
+
+    fn get_encrypted_password(&self) -> Option<&str> {
+        todo!()
+    }
+}
+
+impl Display for Inner {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> Result<(), fmt::Error> {
+        write!(
+            f,
+            "{}:{}:{}:{}",
+            self.groupname,
+            self.password,
+            self.gid,
+            self.members
+                .iter()
+                .filter_map(|mem| if mem.kind == MembershipKind::Member {
+                    Some(format!("{}", mem.username))
+                } else {
+                    None
+                })
+                .collect::<Vec<String>>()
+                .join(",")
+        )
+    }
+}
+
+impl NewFromString for Group {
+    /// Parse a line formatted like one in `/etc/group` and construct a matching [`Group`] instance
+    ///
+    /// # Example
+    /// ```
+    /// use crate::umanux::api::GroupRead;
+    /// use umanux::NewFromString;
+    /// let grp = umanux::Group::new_from_string(
+    ///     "teste:x:1002:test,teste".to_owned(),
+    ///     0,
+    /// ).unwrap();
+    /// assert_eq!(grp.borrow().get_groupname().unwrap(), "teste");
+    /// ```
+    ///
+    /// # Errors
+    /// When parsing fails this function returns a `UserLibError::Message` containing some information as to why the function failed.
+    fn new_from_string(line: String, position: u32) -> Result<Self, UserLibError> {
+        let elements: Vec<String> = line.split(':').map(ToString::to_string).collect();
+        if elements.len() == 4 {
+            Ok(Self::new(RefCell::new(Inner {
+                pos: position,
+                source: line,
+                groupname: Groupname::try_from(elements.get(0).unwrap().to_string())?,
+                password: crate::Password::Disabled,
+                gid: crate::Gid::try_from(elements.get(2).unwrap().to_string())?,
+                members: parse_members_list(elements.get(3).unwrap()),
+            })))
+        } else {
+            Err(format!(
+                "Failed to parse: not enough elements ({}): {:?}",
+                elements.len(),
+                elements
+            )
+            .into())
+        }
+    }
+}
+
+fn parse_members_list(source: &str) -> Vec<Membership> {
+    let mut res = vec![];
+    for mem in source.split(',').filter_map(|x| {
+        if x.is_empty() {
+            None
+        } else {
+            Some(x.to_string())
+        }
+    }) {
+        res.push(Membership {
+            kind: MembershipKind::Member,
+            username: crate::Username::try_from(mem).expect("failed to parse username"),
+        });
+    }
+    res
+}
+
+#[test]
+fn test_parse_and_back_identity() {
+    let line = "teste:x:1002:test,teste";
+    let line2: Group = Group::new_from_string(line.to_owned(), 0).unwrap();
+    assert_eq!(format!("{}", line2.borrow()), line);
+}
+
+#[test]
+fn test_groupname() {
+    let line = "teste:x:1002:test,teste";
+    let line2 = Group::new_from_string(line.to_owned(), 0).unwrap();
+    assert_eq!(line2.borrow().get_groupname().unwrap(), "teste");
+}
+#[test]
+fn test_root_group() {
+    let line = "root:x:0:";
+    let line2 = Group::new_from_string(line.to_owned(), 0).unwrap();
+    assert_eq!(line2.borrow().get_groupname().unwrap(), "root");
+}

src/lib.rs

@@ -1,3 +1,32 @@
-pub mod passwd;
+#![warn(
+    clippy::all,
+    //clippy::restriction,
+    clippy::pedantic,
+    clippy::nursery,
+    clippy::cargo
+)]
+//#![allow(clippy::non_ascii_literal)]
+#![allow(clippy::missing_errors_doc)]
+#![allow(clippy::clippy::multiple_crate_versions)]
 
-pub use passwd::{Password, Username};
+#[macro_use]
+extern crate lazy_static;
+#[macro_use]
+extern crate derive_builder;
+
+extern crate log;
+
+pub mod api;
+pub mod error;
+pub mod group;
+pub mod user;
+pub mod userlib;
+pub use error::UserLibError;
+pub use group::Group;
+pub use user::gecos_fields::Gecos;
+pub use user::passwd_fields::{
+    EncryptedPassword, Gid, HomeDir, Password, ShellPath, Uid, Username,
+};
+pub use user::shadow_fields::Shadow;
+pub use user::User;
+pub use userlib::{files::Files, NewFromString, UserDBLocal};

src/passwd.rs

@@ -1,376 +0,0 @@
-/*#![warn(
-    clippy::all,
-    clippy::restriction,
-    clippy::pedantic,
-    clippy::nursery,
-    clippy::cargo
-)]*/
-use std::cmp::Eq;
-use std::convert::TryFrom;
-use std::fmt::{self, Display};
-
-/// The username of the current user
-///
-/// When done the validity will automatically be checked in the `trait TryFrom`.
-///
-/// In the future some extra fields might be added.
-#[derive(Debug, PartialEq, Eq)]
-pub struct Username<'a> {
-    /// The username value
-    username: &'a str,
-}
-
-#[derive(Debug, PartialEq, Eq)]
-pub struct Password<'a> {
-    password: &'a str,
-}
-
-#[derive(Debug, PartialEq, Eq)]
-pub struct Uid {
-    uid: u32,
-}
-
-#[derive(Debug, PartialEq, Eq)]
-pub struct Gid {
-    gid: u32,
-}
-
-#[derive(Debug, PartialEq, Eq)]
-pub enum Gecos<'a> {
-    Detail {
-        full_name: &'a str,
-        room: &'a str,
-        phone_work: &'a str,
-        phone_home: &'a str,
-        other: &'a str,
-    },
-    Simple {
-        comment: &'a str,
-    },
-}
-
-#[derive(Debug, PartialEq, Eq)]
-pub struct HomeDir<'a> {
-    dir: &'a str,
-}
-
-#[derive(Debug, PartialEq, Eq)]
-pub struct ShellDir<'a> {
-    shell: &'a str,
-}
-
-/// A record in the user database `/etc/passwd`.
-#[derive(Debug, PartialEq, Eq)]
-pub struct Passwd<'a> {
-    username: Username<'a>,  /* Username.  */
-    password: Password<'a>,  /* Hashed passphrase, if shadow database not in use (see shadow.h).  */
-    uid: Uid,                /* User ID.  */
-    gid: Gid,                /* Group ID.  */
-    gecos: Gecos<'a>,        /* Real name.  */
-    home_dir: HomeDir<'a>,   /* Home directory.  */
-    shell_dir: ShellDir<'a>, /* Shell program.  */
-}
-
-impl<'a> Passwd<'a> {
-    pub fn new_from_string(line: &'a str) -> Result<Self, &str> {
-        let elements: Vec<&str> = line.split(":").collect();
-        if elements.len() == 7 {
-            Ok(Passwd {
-                username: Username::try_from(*elements.get(0).unwrap())
-                    .expect("failed to parse username."),
-                password: Password::try_from(*elements.get(1).unwrap())
-                    .expect("Failed to parse Password"),
-                uid: Uid::try_from(*elements.get(2).unwrap()).expect("Failed to parse uid"),
-                gid: Gid::try_from(*elements.get(3).unwrap()).expect("Failed to parse gid"),
-                gecos: Gecos::try_from(*elements.get(4).unwrap())
-                    .expect("Failed to parse Gecos field"),
-                home_dir: HomeDir::try_from(*elements.get(5).unwrap())
-                    .expect("Failed to parse home directory"),
-                shell_dir: ShellDir::try_from(*elements.get(6).unwrap())
-                    .expect("Failed to parse shell directory"),
-            })
-        } else {
-            Err("Failed to parse: not enough elements")
-        }
-    }
-}
-
-impl Default for Passwd<'_> {
-    fn default() -> Self {
-        Passwd {
-            username: Username {
-                username: "defaultuser",
-            },
-            password: Password {
-                password: "notencrypted",
-            },
-            uid: Uid { uid: 1001 },
-            gid: Gid { gid: 1001 },
-            gecos: Gecos::Simple {
-                comment: "gecos default comment",
-            },
-            home_dir: HomeDir {
-                dir: "/home/default",
-            },
-            shell_dir: ShellDir { shell: "/bin/bash" },
-        }
-    }
-}
-
-impl Display for Passwd<'_> {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        write!(
-            f,
-            "{}:{}:{}:{}:{}:{}:{}",
-            self.username,
-            self.password,
-            self.uid,
-            self.gid,
-            self.gecos,
-            self.home_dir,
-            self.shell_dir
-        )
-    }
-}
-
-impl Display for Username<'_> {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        write!(f, "{}", self.username,)
-    }
-}
-
-impl<'a> TryFrom<&'a str> for Username<'a> {
-    type Error = &'static str;
-    fn try_from(source: &'a str) -> std::result::Result<Self, Self::Error> {
-        Ok(Self { username: source })
-    }
-}
-
-impl Display for Password<'_> {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        write!(f, "{}", self.password,)
-    }
-}
-
-impl<'a> TryFrom<&'a str> for Password<'a> {
-    type Error = &'static str;
-    fn try_from(source: &'a str) -> std::result::Result<Self, Self::Error> {
-        Ok(Self { password: source })
-    }
-}
-
-impl Display for Uid {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        write!(f, "{}", self.uid,)
-    }
-}
-
-impl TryFrom<&str> for Uid {
-    type Error = &'static str;
-    fn try_from(source: &str) -> std::result::Result<Self, Self::Error> {
-        Ok(Self {
-            uid: source.parse::<u32>().unwrap(),
-        })
-    }
-}
-
-impl Display for Gid {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        write!(f, "{}", self.gid,)
-    }
-}
-
-impl TryFrom<&str> for Gid {
-    type Error = &'static str;
-    fn try_from(source: &str) -> std::result::Result<Self, Self::Error> {
-        Ok(Self {
-            gid: source.parse::<u32>().unwrap(),
-        })
-    }
-}
-
-impl Display for Gecos<'_> {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        match &self {
-            Gecos::Simple { comment } => write!(f, "{}", comment),
-            Gecos::Detail {
-                full_name,
-                room,
-                phone_work,
-                phone_home,
-                other,
-            } => write!(
-                f,
-                "{},{},{},{},{}",
-                full_name, room, phone_work, phone_home, other
-            ),
-        }
-    }
-}
-
-impl<'a> TryFrom<&'a str> for Gecos<'a> {
-    type Error = &'static str;
-    fn try_from(source: &'a str) -> std::result::Result<Self, Self::Error> {
-        let vals: Vec<&str> = source.split(',').collect();
-        if vals.len() == 5 {
-            Ok(Gecos::Detail {
-                full_name: vals.get(0).unwrap(),
-                room: vals.get(1).unwrap(),
-                phone_work: vals.get(2).unwrap(),
-                phone_home: vals.get(3).unwrap(),
-                other: vals.get(4).unwrap(),
-            })
-        } else if vals.len() == 4 {
-            Ok(Gecos::Detail {
-                full_name: vals.get(0).unwrap(),
-                room: vals.get(1).unwrap(),
-                phone_work: vals.get(2).unwrap(),
-                phone_home: vals.get(3).unwrap(),
-                other: "",
-            })
-        }
-        else if vals.len() == 1 {
-            Ok(Gecos::Simple {
-                comment: vals.get(0).unwrap(),
-            })
-        } else {
-            panic!(format!("Could not parse this string: {}", source))
-        }
-    }
-}
-
-impl Display for HomeDir<'_> {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        write!(f, "{}", self.dir,)
-    }
-}
-
-impl<'a> TryFrom<&'a str> for HomeDir<'a> {
-    type Error = &'static str;
-    fn try_from(source: &'a str) -> std::result::Result<Self, Self::Error> {
-        Ok(Self { dir: source })
-    }
-}
-
-impl Display for ShellDir<'_> {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        write!(f, "{}", self.shell,)
-    }
-}
-
-impl<'a> TryFrom<&'a str> for ShellDir<'a> {
-    type Error = &'static str;
-    fn try_from(source: &'a str) -> std::result::Result<Self, Self::Error> {
-        Ok(Self { shell: source })
-    }
-}
-
-// Tests ----------------------------------------------------------------------
-
-#[test]
-fn test_default_user() {
-    // Check if a user can be created.
-    let pwd = Passwd::default();
-    assert_eq!(pwd.username.username, "defaultuser");
-    assert_eq!(pwd.home_dir.dir, "/home/default");
-    assert_eq!(pwd.uid.uid, 1001);
-}
-
-#[test]
-fn test_parse_gecos() {
-    // test if the Gecos field can be parsed and the resulting struct is populated correctly.
-    let gcd = "Full Name,504,11345342,ä1-2312,myemail@test.com";
-    let gcs = "A böring comment →";
-    let gc_no_other: &str = "systemd Network Management,,,";
-    let res_detail = Gecos::try_from(gcd).unwrap();
-    let res_simple = Gecos::try_from(gcs).unwrap();
-    let res_no_other = Gecos::try_from(gc_no_other).unwrap();
-    match res_simple {
-        Gecos::Simple { comment } => assert_eq!(comment, "A böring comment →"),
-        _ => unreachable!(),
-    }
-    match res_detail {
-        Gecos::Detail {
-            full_name,
-            room,
-            phone_work,
-            phone_home,
-            other,
-        } => {
-            assert_eq!(full_name, "Full Name");
-            assert_eq!(room, "504");
-            assert_eq!(phone_work, "11345342");
-            assert_eq!(phone_home, "ä1-2312");
-            assert_eq!(other, "myemail@test.com");
-        }
-        _ => unreachable!(),
-    }
-    match res_no_other {
-        Gecos::Detail {
-            full_name,
-            room,
-            phone_work,
-            phone_home,
-            other,
-        } => {
-            assert_eq!(full_name, "systemd Network Management");
-            assert_eq!(room, "");
-            assert_eq!(phone_work, "");
-            assert_eq!(phone_home, "");
-            assert_eq!(other, "");
-        }
-        _ => unreachable!(),
-    }
-}
-
-#[test]
-fn test_new_from_string() {
-    // Test if a single line can be parsed and if the resulting struct is populated correctly.
-    let pwd =
-        Passwd::new_from_string("testuser:testpassword:1001:1001:testcomment:/home/test:/bin/test")
-            .unwrap();
-    let pwd2 =
-        Passwd::new_from_string("testuser:testpassword:1001:1001:full Name,004,000342,001-2312,myemail@test.com:/home/test:/bin/test")
-            .unwrap();
-    assert_eq!(pwd.username.username, "testuser");
-    assert_eq!(pwd.home_dir.dir, "/home/test");
-    assert_eq!(pwd.uid.uid, 1001);
-    match pwd.gecos {
-        Gecos::Simple { comment } => assert_eq!(comment, "testcomment"),
-        _ => unreachable!(),
-    }
-    match pwd2.gecos {
-        Gecos::Detail {
-            full_name,
-            room,
-            phone_work,
-            phone_home,
-            other,
-        } => {
-            assert_eq!(full_name, "full Name");
-            assert_eq!(room, "004");
-            assert_eq!(phone_work, "000342");
-            assert_eq!(phone_home, "001-2312");
-            assert_eq!(other, "myemail@test.com");
-        }
-        _ => unreachable!(),
-    }
-}
-
-#[test]
-fn test_parse_passwd() {
-    // Test wether the passwd file can be parsed and recreated without throwing an exception
-    use std::fs::File;
-    use std::io::{prelude::*, BufReader};
-    let file = File::open("/etc/passwd").unwrap();
-    let reader = BufReader::new(file);
-
-    for line in reader.lines() {
-        let lineorig: String = line.unwrap();
-        assert_eq!(
-            // ignoring the numbers of `,` since the implementation does not (yet) reproduce a missing comment field.
-            format!("{}", Passwd::new_from_string(&lineorig.clone()).unwrap()).replace(",",""),
-            lineorig.replace(",","")
-        );
-    }
-}

src/user/gecos_fields.rs

@@ -0,0 +1,225 @@
+#![allow(clippy::non_ascii_literal)]
+use crate::UserLibError;
+use std::cmp::Eq;
+use std::convert::TryFrom;
+use std::fmt::{self, Display};
+/// The gecos field of a user.
+///
+/// In the `/etc/passwd` file this field is a `,` sepparated list of items.
+/// The first 4 values are more or less standardised to be full name, room, phone at work and phone at home. After that there can be some extra fields often containing the emailadress and even additional information.
+///
+/// This enum represents the first 4 values by name and adds the other values to a list of strings [`Gecos::Detail`]. If only one field is found and no `,` at all this value is used as a human readable comment [`Gecos::Simple`].
+#[derive(Debug, PartialEq, Eq, Clone)]
+pub enum Gecos {
+    Detail {
+        full_name: String,
+        room: String,
+        phone_work: String,
+        phone_home: String,
+        other: Option<Vec<String>>,
+    },
+    Simple {
+        comment: String,
+    },
+}
+
+impl Gecos {
+    #[must_use]
+    pub fn get_comment(&self) -> Option<&str> {
+        match &self {
+            Self::Simple { comment, .. } => Some(comment),
+            Self::Detail { .. } => None,
+        }
+    }
+    #[must_use]
+    pub fn get_full_name(&self) -> Option<&str> {
+        match &self {
+            Self::Simple { .. } => None,
+            Self::Detail { full_name, .. } => {
+                if full_name.is_empty() {
+                    None
+                } else {
+                    Some(full_name)
+                }
+            }
+        }
+    }
+    #[must_use]
+    pub fn get_room(&self) -> Option<&str> {
+        match &self {
+            Self::Simple { .. } => None,
+            Self::Detail { room, .. } => {
+                if room.is_empty() {
+                    None
+                } else {
+                    Some(room)
+                }
+            }
+        }
+    }
+    #[must_use]
+    pub fn get_phone_work(&self) -> Option<&str> {
+        match &self {
+            Self::Simple { .. } => None,
+            Self::Detail { phone_work, .. } => {
+                if phone_work.is_empty() {
+                    None
+                } else {
+                    Some(phone_work)
+                }
+            }
+        }
+    }
+    #[must_use]
+    pub fn get_phone_home(&self) -> Option<&str> {
+        match &self {
+            Self::Simple { .. } => None,
+            Self::Detail { phone_home, .. } => {
+                if phone_home.is_empty() {
+                    None
+                } else {
+                    Some(phone_home)
+                }
+            }
+        }
+    }
+    #[must_use]
+    pub const fn get_other(&self) -> Option<&Vec<String>> {
+        match self {
+            Self::Simple { .. } => None,
+            Self::Detail { other, .. } => match other {
+                None => None,
+                Some(comments) => Some(comments),
+            },
+        }
+    }
+}
+
+impl Display for Gecos {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        match &self {
+            Self::Simple { comment } => write!(f, "{}", comment),
+            Self::Detail {
+                full_name,
+                room,
+                phone_work,
+                phone_home,
+                other,
+            } => write!(
+                f,
+                "{},{},{},{}{}",
+                full_name,
+                room,
+                phone_work,
+                phone_home,
+                match other {
+                    None => "".to_string(),
+                    Some(cont) => format!(",{}", cont.join(",")),
+                }
+            ),
+        }
+    }
+}
+
+impl TryFrom<String> for Gecos {
+    type Error = UserLibError;
+    fn try_from(source: String) -> std::result::Result<Self, Self::Error> {
+        let vals: Vec<String> = source.split(',').map(ToString::to_string).collect();
+        if vals.len() > 3 {
+            Ok(Self::Detail {
+                full_name: vals[0].clone(),
+                room: vals[1].clone(),
+                phone_work: vals[2].clone(),
+                phone_home: vals[3].clone(),
+                other: if vals.len() == 4 {
+                    None
+                } else {
+                    Some(vals[4..].to_vec())
+                },
+            })
+        } else if vals.len() == 1 {
+            Ok(Self::Simple {
+                comment: vals.get(0).unwrap().into(),
+            })
+        } else {
+            panic!(format!("Could not parse this string: {}", source))
+        }
+    }
+}
+#[test]
+fn test_parse_gecos() {
+    // test if the Gecos field can be parsed and the resulting struct is populated correctly.
+    let gcdetail = "Full Name,504,11345342,ä1-2312,myemail@test.com".to_string();
+    let gcsimple = "A böring comment →".to_string();
+    let gc_no_other = "systemd Network Management,,,".to_string();
+    let res_detail = crate::Gecos::try_from(gcdetail).unwrap();
+    let res_simple = crate::Gecos::try_from(gcsimple).unwrap();
+    let res_no_other = crate::Gecos::try_from(gc_no_other).unwrap();
+    match res_simple {
+        crate::Gecos::Simple { comment } => assert_eq!(comment, "A böring comment →"),
+        _ => unreachable!(),
+    }
+    match res_detail {
+        crate::Gecos::Detail {
+            full_name,
+            room,
+            phone_work,
+            phone_home,
+            other,
+        } => {
+            assert_eq!(full_name, "Full Name");
+            assert_eq!(room, "504");
+            assert_eq!(phone_work, "11345342");
+            assert_eq!(phone_home, "ä1-2312");
+            assert_eq!(other.unwrap()[0], "myemail@test.com");
+        }
+        _ => unreachable!(),
+    }
+    match res_no_other {
+        crate::Gecos::Detail {
+            full_name,
+            room,
+            phone_work,
+            phone_home,
+            other,
+        } => {
+            assert_eq!(full_name, "systemd Network Management");
+            assert_eq!(room, "");
+            assert_eq!(phone_work, "");
+            assert_eq!(phone_home, "");
+            assert_eq!(other, None);
+        }
+        _ => unreachable!(),
+    }
+}
+
+#[test]
+fn test_gecos_getters() {
+    // test if the Gecos field can be parsed and the resulting struct is populated correctly.
+    let gcdetail = "Full Name,504,11345342,ä1-2312,myemail@test.com".to_string();
+    let gcsimple = "A böring comment →".to_string();
+    let gc_no_other = "systemd Network Management,,,".to_string();
+    let res_detail = crate::Gecos::try_from(gcdetail).unwrap();
+    let res_simple = crate::Gecos::try_from(gcsimple).unwrap();
+    let res_no_other = crate::Gecos::try_from(gc_no_other).unwrap();
+    assert_eq!(res_simple.get_comment(), Some("A böring comment →"));
+
+    assert_eq!(res_detail.get_comment(), None);
+    assert_eq!(res_detail.get_full_name(), Some("Full Name"));
+    assert_eq!(res_detail.get_room(), Some("504"));
+    assert_eq!(res_detail.get_phone_work(), Some("11345342"));
+    assert_eq!(res_detail.get_phone_home(), Some("ä1-2312"));
+    assert_eq!(
+        res_detail.get_other(),
+        Some(&vec!["myemail@test.com".to_string()])
+    );
+
+    assert_eq!(
+        res_no_other.get_full_name(),
+        Some("systemd Network Management")
+    );
+    assert_eq!(res_no_other.get_room(), None);
+    assert_eq!(res_no_other.get_phone_work(), None);
+    assert_eq!(res_no_other.get_phone_home(), None);
+    assert_eq!(res_no_other.get_other(), None);
+}

src/user/mod.rs

@@ -0,0 +1,312 @@
+pub mod gecos_fields;
+
+pub mod passwd_fields;
+pub mod shadow_fields;
+
+use crate::userlib::NewFromString;
+#[allow(unused_imports)]
+use log::{debug, error, info, trace, warn};
+use std::convert::TryFrom;
+use std::fmt::{self, Display};
+
+/// A record(line) in the user database `/etc/passwd` found in most linux systems.
+#[derive(Debug, PartialEq, Eq, Clone)]
+pub struct User {
+    source: String,
+    pos: u32,
+    username: crate::Username,            /* Username.  */
+    pub(crate) password: crate::Password, /* Hashed passphrase, if shadow database not in use (see shadow.h).  */
+    uid: crate::Uid,                      /* User ID.  */
+    gid: crate::Gid,                      /* Group ID.  */
+    gecos: crate::Gecos,                  /* Real name.  */
+    home_dir: crate::HomeDir,             /* Home directory.  */
+    shell_path: crate::ShellPath,         /* Shell program.  */
+    groups: Vec<(crate::group::MembershipKind, crate::Group)>,
+}
+
+impl User {
+    #[must_use]
+    pub const fn get_shadow(&self) -> Option<&crate::Shadow> {
+        match self.password {
+            crate::Password::Encrypted(_) | crate::Password::Disabled => None,
+            crate::Password::Shadow(ref s) => Some(s),
+        }
+    }
+    #[must_use]
+    pub fn remove_in(&self, content: &str) -> String {
+        content
+            .split(&self.source)
+            .map(str::trim)
+            .collect::<Vec<&str>>()
+            .join("\n")
+    }
+    pub fn username(&mut self, name: String) -> &mut Self {
+        self.username = crate::Username { username: name };
+        if let crate::Password::Shadow(ref mut s) = self.password {
+            s.set_username(self.username.clone());
+        }
+        self
+    }
+    pub fn disable_password(&mut self) -> &mut Self {
+        self.password = crate::Password::Disabled;
+        self
+    }
+    pub fn uid(&mut self, uid: u32) -> &mut Self {
+        self.uid = crate::Uid { uid };
+        self
+    }
+    pub fn gid(&mut self, gid: u32) -> &mut Self {
+        self.gid = crate::Gid { gid };
+        self
+    }
+    pub fn home_dir(&mut self, path: String) -> &mut Self {
+        self.home_dir = crate::HomeDir { dir: path };
+        self
+    }
+    pub fn shell_path(&mut self, path: String) -> &mut Self {
+        self.shell_path = crate::ShellPath { shell: path };
+        self
+    }
+
+    pub fn add_group(
+        &mut self,
+        group_type: crate::group::MembershipKind,
+        group: crate::Group,
+    ) -> &mut Self {
+        self.groups.push((group_type, group));
+        self
+    }
+
+    #[must_use]
+    pub const fn get_groups(&self) -> &Vec<(crate::group::MembershipKind, crate::Group)> {
+        &self.groups
+    }
+}
+
+impl NewFromString for User {
+    /// Parse a line formatted like one in `/etc/passwd` and construct a matching [`User`] instance
+    ///
+    /// # Example
+    /// ```
+    /// use crate::umanux::api::UserRead;
+    /// use umanux::NewFromString;
+    /// let pwd = umanux::User::new_from_string(
+    ///     "testuser:testpassword:1001:1001:full Name,,,,:/home/test:/bin/test".to_string(), 0).unwrap();
+    /// assert_eq!(pwd.get_username().unwrap(), "testuser");
+    /// ```
+    ///
+    /// # Errors
+    /// When parsing fails this function returns a [`UserLibError::Message`](crate::userlib_error::UserLibError::Message) containing some information as to why the function failed.
+    fn new_from_string(line: String, position: u32) -> Result<Self, crate::UserLibError>
+    where
+        Self: Sized,
+    {
+        let elements: Vec<String> = line.split(':').map(ToString::to_string).collect();
+        if elements.len() == 7 {
+            Ok(Self {
+                source: line,
+                pos: position,
+                username: crate::Username::try_from(elements.get(0).unwrap().to_string())?,
+                password: crate::Password::Encrypted(crate::EncryptedPassword::try_from(
+                    elements.get(1).unwrap().to_string(),
+                )?),
+                uid: crate::Uid::try_from(elements.get(2).unwrap().to_string())?,
+                gid: crate::Gid::try_from(elements.get(3).unwrap().to_string())?,
+                gecos: crate::Gecos::try_from(elements.get(4).unwrap().to_string())?,
+                home_dir: crate::HomeDir::try_from(elements.get(5).unwrap().to_string())?,
+                shell_path: crate::ShellPath::try_from(elements.get(6).unwrap().to_string())?,
+                groups: Vec::new(),
+            })
+        } else {
+            Err("Failed to parse: not enough elements".into())
+        }
+    }
+}
+
+impl crate::api::UserRead for User {
+    #[must_use]
+    fn get_username(&self) -> Option<&str> {
+        Some(&self.username.username)
+    }
+    #[must_use]
+    fn get_password(&self) -> Option<&str> {
+        match &self.password {
+            crate::Password::Encrypted(crate::EncryptedPassword { password }) => Some(password),
+            crate::Password::Shadow(crate::Shadow { ref password, .. }) => Some(&password.password),
+            crate::Password::Disabled => None,
+        }
+    }
+    #[must_use]
+    fn get_uid(&self) -> u32 {
+        self.uid.uid
+    }
+    #[must_use]
+    fn get_gid(&self) -> u32 {
+        self.gid.gid
+    }
+    #[must_use]
+    fn get_gecos(&self) -> Option<&crate::Gecos> {
+        Some(&self.gecos)
+    }
+    #[must_use]
+    fn get_home_dir(&self) -> Option<&str> {
+        Some(&self.home_dir.dir)
+    }
+    #[must_use]
+    fn get_shell_path(&self) -> Option<&str> {
+        Some(&self.shell_path.shell)
+    }
+
+    #[must_use]
+    fn get_full_name(&self) -> Option<&str> {
+        self.gecos.get_full_name()
+    }
+
+    #[must_use]
+    fn get_room(&self) -> Option<&str> {
+        self.gecos.get_room()
+    }
+
+    #[must_use]
+    fn get_phone_work(&self) -> Option<&str> {
+        self.gecos.get_phone_work()
+    }
+
+    #[must_use]
+    fn get_phone_home(&self) -> Option<&str> {
+        self.gecos.get_phone_home()
+    }
+
+    #[must_use]
+    fn get_other(&self) -> Option<&Vec<String>> {
+        self.gecos.get_other()
+    }
+}
+
+impl PartialOrd for User {
+    fn partial_cmp(&self, other: &Self) -> Option<std::cmp::Ordering> {
+        Some(self.pos.cmp(&other.pos))
+    }
+}
+
+impl Ord for User {
+    fn cmp(&self, other: &Self) -> std::cmp::Ordering {
+        self.pos.cmp(&other.pos)
+    }
+}
+
+impl Default for User {
+    fn default() -> Self {
+        let username = passwd_fields::Username {
+            username: "defaultusername".to_owned(),
+        };
+        let line = "defaultusername:!!:0:0:99999:7:::";
+        let password = passwd_fields::Password::Shadow(
+            shadow_fields::Shadow::new_from_string(line.to_owned(), u32::MAX).unwrap(),
+        );
+        Self {
+            source: "".to_owned(),
+            pos: u32::MAX,
+            username,
+            password,
+            uid: crate::Uid { uid: 1001 },
+            gid: crate::Gid { gid: 1001 },
+            gecos: crate::Gecos::Simple {
+                comment: "".to_string(),
+            },
+            home_dir: crate::HomeDir {
+                dir: "/".to_owned(),
+            },
+            shell_path: crate::ShellPath {
+                shell: "/bin/nologin".to_owned(),
+            },
+            groups: Vec::new(),
+        }
+    }
+}
+
+impl Display for User {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(
+            f,
+            "{}:{}:{}:{}:{}:{}:{}",
+            self.username,
+            self.password,
+            self.uid,
+            self.gid,
+            self.gecos,
+            self.home_dir,
+            self.shell_path
+        )
+    }
+}
+
+#[test]
+fn test_default_user() {
+    // Check if a user can be created.
+    let mut pwd = User::default();
+    assert_eq!(pwd.username.username, "defaultusername");
+    assert_eq!(pwd.home_dir.dir, "/");
+    assert_eq!(pwd.uid.uid, 1001);
+    let npw = pwd.username("test".to_owned()).clone();
+    assert_eq!(npw.username.username, "test");
+}
+
+#[test]
+fn test_new_from_string() {
+    // Test if a single line can be parsed and if the resulting struct is populated correctly.
+    let fail = User::new_from_string("".into(), 0).err().unwrap();
+    assert_eq!(fail, "Failed to parse: not enough elements".into());
+    let pwd = User::new_from_string(
+        "testuser:testpassword:1001:1001:testcomment:/home/test:/bin/test".into(),
+        0,
+    )
+    .unwrap();
+    let pwd2 =
+        User::new_from_string("testuser:testpassword:1001:1001:full Name,004,000342,001-2312,myemail@test.com:/home/test:/bin/test".into(),0)
+            .unwrap();
+    assert_eq!(pwd.username.username, "testuser");
+    assert_eq!(pwd.home_dir.dir, "/home/test");
+    assert_eq!(pwd.uid.uid, 1001);
+    match pwd.gecos {
+        crate::Gecos::Simple { comment } => assert_eq!(comment, "testcomment"),
+        _ => unreachable!(),
+    }
+    match pwd2.gecos {
+        crate::Gecos::Detail {
+            full_name,
+            room,
+            phone_work,
+            phone_home,
+            other,
+        } => {
+            assert_eq!(full_name, "full Name");
+            assert_eq!(room, "004");
+            assert_eq!(phone_work, "000342");
+            assert_eq!(phone_home, "001-2312");
+            assert_eq!(other.unwrap()[0], "myemail@test.com");
+        }
+        _ => unreachable!(),
+    }
+}
+
+#[test]
+fn test_parse_passwd() {
+    // Test wether the passwd file can be parsed and recreated without throwing an exception
+    use std::convert::TryInto;
+    use std::fs::File;
+    use std::io::{prelude::*, BufReader};
+    let file = File::open("/etc/passwd").unwrap();
+    let reader = BufReader::new(file);
+
+    for (n, line) in reader.lines().enumerate() {
+        let lineorig: String = line.unwrap();
+        let linecopy = lineorig.clone();
+        let pass_struc = User::new_from_string(linecopy, n.try_into().unwrap()).unwrap();
+        assert_eq!(
+            // ignoring the numbers of `,` since the implementation does not (yet) reproduce a missing comment field.
+            lineorig,
+            format!("{}", pass_struc)
+        );
+    }
+}

src/user/passwd_fields.rs

@@ -0,0 +1,229 @@
+#![allow(clippy::non_ascii_literal)]
+
+use log::warn;
+use regex::Regex;
+
+use crate::UserLibError;
+use std::cmp::Eq;
+use std::convert::TryFrom;
+use std::fmt::{self, Display};
+
+/// The username of the current user
+///
+/// When done the validity will automatically be checked in the `trait TryFrom`.
+///
+/// In the future some extra fields might be added.
+#[derive(Debug, PartialEq, Eq, Clone)]
+pub struct Username {
+    /// The username value
+    pub(crate) username: String,
+}
+
+impl Display for Username {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "{}", self.username,)
+    }
+}
+
+impl TryFrom<String> for Username {
+    type Error = UserLibError;
+    fn try_from(source: String) -> std::result::Result<Self, Self::Error> {
+        if is_username_valid(&source) {
+            Ok(Self { username: source })
+        } else if source == "Debian-exim" {
+            warn!("username {} is not a valid username. This might cause problems. (It is default in Debian and Ubuntu)", source);
+            Ok(Self { username: source })
+        } else {
+            Err(format!("Invalid username {}", source).into())
+        }
+    }
+}
+
+pub(crate) fn is_username_valid(name: &str) -> bool {
+    lazy_static! {
+        static ref USERVALIDATION: Regex =
+            Regex::new("^[a-z_]([a-z0-9_\\-]{0,31}|[a-z0-9_\\-]{0,30}\\$)$").unwrap();
+    }
+    USERVALIDATION.is_match(name)
+}
+
+#[derive(Debug, PartialEq, Eq, Clone)]
+pub enum Password {
+    Encrypted(crate::EncryptedPassword),
+    Shadow(crate::Shadow),
+    Disabled,
+}
+
+impl Display for Password {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        match self {
+            Self::Encrypted(EncryptedPassword { password }) => write!(f, "{}", password,),
+            Self::Shadow(_) | Self::Disabled => write!(f, "x"),
+        }
+    }
+}
+
+#[derive(Debug, PartialEq, Eq, Clone)]
+pub struct EncryptedPassword {
+    pub(in crate::user) password: String,
+}
+
+impl Display for EncryptedPassword {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(f, "{}", self.password,)
+    }
+}
+
+impl TryFrom<String> for EncryptedPassword {
+    type Error = UserLibError;
+    fn try_from(source: String) -> std::result::Result<Self, Self::Error> {
+        /*if source == "x" {
+            //warn!("password from shadow not loaded!")
+        } else {
+            //warn!("Password field has an unexpected value")
+        };*/
+        Ok(Self { password: source })
+    }
+}
+
+#[derive(Debug, PartialEq, Eq, Clone)]
+pub struct Uid {
+    pub(in crate::user) uid: u32,
+}
+
+impl Display for Uid {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "{}", self.uid,)
+    }
+}
+
+impl TryFrom<String> for Uid {
+    type Error = UserLibError;
+    fn try_from(source: String) -> std::result::Result<Self, Self::Error> {
+        Ok(Self {
+            uid: source.parse::<u32>().unwrap(),
+        })
+    }
+}
+
+impl Uid {
+    #[must_use]
+    pub const fn is_system_uid(&self) -> bool {
+        // since it is a u32  it cannot be smaller than 0
+        self.uid < 1000
+    }
+}
+
+#[derive(Debug, PartialEq, Eq, Clone)]
+pub struct Gid {
+    pub(in crate::user) gid: u32,
+}
+
+impl Display for Gid {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "{}", self.gid,)
+    }
+}
+
+impl TryFrom<String> for Gid {
+    type Error = UserLibError;
+    fn try_from(source: String) -> std::result::Result<Self, Self::Error> {
+        Ok(Self {
+            gid: source.parse::<u32>().unwrap(),
+        })
+    }
+}
+
+impl Gid {
+    #[must_use]
+    pub const fn is_system_gid(&self) -> bool {
+        // since it is a u32  it cannot be smaller than 0
+        self.gid < 1000
+    }
+
+    #[must_use]
+    pub const fn get_gid(&self) -> u32 {
+        self.gid
+    }
+}
+
+/// The home directory of a user
+#[derive(Debug, PartialEq, Eq, Clone)]
+pub struct HomeDir {
+    pub(in crate::user) dir: String,
+}
+
+impl Display for HomeDir {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "{}", self.dir,)
+    }
+}
+
+impl TryFrom<String> for HomeDir {
+    type Error = UserLibError;
+    fn try_from(source: String) -> std::result::Result<Self, Self::Error> {
+        Ok(Self { dir: source })
+    }
+}
+
+/// The path to the Shell binary
+#[derive(Debug, PartialEq, Eq, Clone)]
+pub struct ShellPath {
+    pub(in crate::user) shell: String,
+}
+
+impl Display for ShellPath {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "{}", self.shell,)
+    }
+}
+
+impl TryFrom<String> for ShellPath {
+    type Error = UserLibError;
+    fn try_from(source: String) -> std::result::Result<Self, Self::Error> {
+        Ok(Self { shell: source })
+    }
+}
+
+// Tests ----------------------------------------------------------------------
+
+#[test]
+fn test_username_validation() {
+    // Failing tests
+    let umlauts: Result<Username, UserLibError> = Username::try_from("täst".to_owned()); // umlauts
+    assert_eq!(Err("Invalid username täst".into()), umlauts);
+    let number_first = Username::try_from("11elf".to_owned()); // numbers first
+    assert_eq!(Err("Invalid username 11elf".into()), number_first);
+    let slashes = Username::try_from("test/name".to_owned()); // slashes in the name
+    assert_eq!(Err("Invalid username test/name".into()), slashes);
+    let long = Username::try_from("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa".to_owned()); // maximum size 32 letters
+    assert_eq!(
+        Err("Invalid username aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa".into()),
+        long
+    );
+    // Working tests
+    let ubuntu_exception = Username::try_from("Debian-exim".to_owned()); // for some reason ubuntu and debian have a capital user.
+    assert_eq!(ubuntu_exception.unwrap().username, "Debian-exim");
+    let single = Username::try_from("t".to_owned()); // single characters are ok
+    assert_eq!(single.unwrap().username, "t");
+    let normal = Username::try_from("superman".to_owned()); // regular username
+    assert_eq!(normal.unwrap().username, "superman");
+    let normal = Username::try_from("anna3pete".to_owned()); // regular username containing a number
+    assert_eq!(normal.unwrap().username, "anna3pete");
+    let normal = Username::try_from("enya$".to_owned()); // regular username ending in a $
+    assert_eq!(normal.unwrap().username, "enya$");
+}
+
+#[test]
+fn test_guid_system_user() {
+    // Check uids of system users.
+    let values = vec![
+        ("999".to_owned(), true),
+        ("0".to_owned(), true),
+        ("1000".to_owned(), false),
+    ];
+    for val in values {
+        assert_eq!(Uid::try_from(val.0.clone()).unwrap().is_system_uid(), val.1);
+        assert_eq!(Gid::try_from(val.0.clone()).unwrap().is_system_gid(), val.1);
+    }
+}

src/user/shadow_fields.rs

@@ -0,0 +1,158 @@
+use crate::userlib::NewFromString;
+
+use crate::UserLibError;
+use std::cmp::Eq;
+use std::convert::TryFrom;
+use std::fmt::{self, Debug, Display};
+
+/// A record(line) in the user database `/etc/shadow` found in most linux systems.
+#[derive(Debug, PartialEq, Eq, Clone)]
+pub struct Shadow {
+    pos: u32,
+    source: String,
+    username: crate::Username,                      /* Username.  */
+    pub(crate) password: crate::EncryptedPassword,  /* Hashed passphrase */
+    last_change: Option<chrono::NaiveDateTime>,     /* User ID.  */
+    earliest_change: Option<chrono::NaiveDateTime>, /* Group ID.  */
+    latest_change: Option<chrono::NaiveDateTime>,   /* Real name.  */
+    warn_period: Option<chrono::Duration>,          /* Home directory.  */
+    deactivated: Option<chrono::Duration>,          /* Shell program.  */
+    deactivated_since: Option<chrono::Duration>,    /* Shell program.  */
+    extensions: Option<u64>,                        /* Shell program.  */
+}
+
+impl Shadow {
+    #[must_use]
+    pub fn get_username(&self) -> &str {
+        &self.username.username
+    }
+
+    pub fn set_username(&mut self, username: crate::Username) {
+        self.username = username;
+    }
+
+    #[must_use]
+    pub fn get_password(&self) -> &str {
+        &self.password.password
+    }
+    #[must_use]
+    pub fn remove_in(&self, content: &str) -> String {
+        content
+            .split(&self.source)
+            .map(str::trim)
+            .collect::<Vec<&str>>()
+            .join("\n")
+    }
+}
+
+impl Display for Shadow {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> Result<(), fmt::Error> {
+        write!(
+            f,
+            "{}:{}:{}:{}:{}:{}:{}:{}:{}",
+            self.username,
+            self.password,
+            show_option_date(self.last_change),
+            show_option_date(self.earliest_change),
+            show_option_date(self.latest_change),
+            show_option_duration(self.warn_period),
+            show_option_duration(self.deactivated),
+            show_option_duration(self.deactivated_since),
+            if self.extensions.is_none() {
+                "".to_string()
+            } else {
+                self.extensions.unwrap().to_string()
+            }
+        )
+    }
+}
+
+fn show_option_date(input: Option<chrono::NaiveDateTime>) -> String {
+    if input.is_none() {
+        "".into()
+    } else {
+        format!("{}", input.unwrap().timestamp() / SECONDS_PER_DAY)
+    }
+}
+
+fn show_option_duration(input: Option<chrono::Duration>) -> String {
+    if input.is_none() {
+        "".into()
+    } else {
+        format!("{}", input.unwrap().num_days())
+    }
+}
+
+impl NewFromString for Shadow {
+    /// Parse a line formatted like one in `/etc/shadow` and construct a matching `Shadow` instance
+    ///
+    /// # Example
+    /// ```
+    /// use umanux::NewFromString;
+    /// let shad = umanux::Shadow::new_from_string(
+    ///     "test:$6$u0Hh.9WKRF1Aeu4g$XqoDyL6Re/4ZLNQCGAXlNacxCxbdigexEqzFzkOVPV5Z1H23hlenjW8ZLgq6GQtFURYwenIFpo1c.r4aW9l5S/:18260:0:99999:7:::".to_string(),
+    ///     0,
+    /// ).unwrap();
+    /// assert_eq!(shad.get_username(), "test");
+    /// ```
+    ///
+    /// # Errors
+    /// When parsing fails this function returns a `UserLibError::Message` containing some information as to why the function failed.
+    fn new_from_string(line: String, position: u32) -> Result<Self, UserLibError> {
+        let elements: Vec<String> = line.split(':').map(ToString::to_string).collect();
+        if elements.len() == 9 {
+            let extra = elements.get(8).unwrap();
+            Ok(Self {
+                pos: position,
+                source: line,
+                username: crate::Username::try_from(elements.get(0).unwrap().to_string())?,
+                password: crate::EncryptedPassword::try_from(elements.get(1).unwrap().to_string())?,
+                last_change: date_since_epoch(elements.get(2).unwrap()),
+                earliest_change: date_since_epoch(elements.get(3).unwrap()),
+                latest_change: date_since_epoch(elements.get(4).unwrap()),
+                warn_period: duration_for_days(elements.get(5).unwrap()),
+                deactivated: duration_for_days(elements.get(6).unwrap()),
+                deactivated_since: duration_for_days(elements.get(7).unwrap()),
+                extensions: if extra.is_empty() {
+                    None
+                } else {
+                    Some(extra.parse::<u64>().unwrap())
+                },
+            })
+        } else {
+            Err(format!(
+                "Failed to parse: not enough elements ({}): {:?}",
+                elements.len(),
+                elements
+            )
+            .into())
+        }
+    }
+}
+
+const SECONDS_PER_DAY: i64 = 86400;
+
+fn date_since_epoch(days_since_epoch: &str) -> Option<chrono::NaiveDateTime> {
+    if days_since_epoch.is_empty() {
+        None
+    } else {
+        let days: i64 = days_since_epoch.parse::<i64>().unwrap();
+        let seconds = days * SECONDS_PER_DAY;
+        Some(chrono::NaiveDateTime::from_timestamp(seconds, 0))
+    }
+}
+fn duration_for_days(days_source: &str) -> Option<chrono::Duration> {
+    if days_source.is_empty() {
+        None
+    } else {
+        let days: i64 = days_source.parse::<i64>().unwrap();
+        Some(chrono::Duration::days(days))
+    }
+}
+
+#[test]
+fn test_parse_and_back_identity() {
+    let line = "test:$6$u0Hh.9WKRF1Aeu4g$XqoDyL6Re/4ZLNQCGAXlNacxCxbdigexEqzFzkOVPV5Z1H23hlenjW8ZLgq6GQtFURYwenIFpo1c.r4aW9l5S/:18260:0:99999:7:::";
+    let line2 = Shadow::new_from_string(line.to_owned(), 0).unwrap();
+    assert_eq!(format!("{}", line2), line);
+}

src/userlib/files.rs

@@ -0,0 +1,275 @@
+use std::{io::Seek, io::SeekFrom, path::PathBuf};
+
+#[allow(unused_imports)]
+use log::{debug, error, info, trace, warn};
+use std::fs::{File, OpenOptions};
+use std::io::Read;
+use std::io::Write;
+use std::ops::Deref;
+
+#[derive(Debug)]
+pub struct Files {
+    pub passwd: Option<PathBuf>,
+    pub shadow: Option<PathBuf>,
+    pub group: Option<PathBuf>,
+}
+
+impl Default for Files {
+    /// use the default Linux `/etc/` paths
+    fn default() -> Self {
+        Self {
+            passwd: Some(PathBuf::from("/etc/passwd")),
+            shadow: Some(PathBuf::from("/etc/shadow")),
+            group: Some(PathBuf::from("/etc/group")),
+        }
+    }
+}
+
+impl Files {
+    /// Check if all the files are defined. Because some operations require the files to be present
+    #[must_use]
+    pub const fn is_virtual(&self) -> bool {
+        !(self.group.is_some() & self.passwd.is_some() & self.shadow.is_some())
+    }
+    pub fn lock_and_get_passwd(&self) -> Result<LockedFileGuard, crate::UserLibError> {
+        let path = self.passwd.as_ref();
+        match path {
+            Some(p) => LockedFileGuard::new(p),
+            None => Err(crate::UserLibError::FilesRequired),
+        }
+    }
+    pub fn lock_and_get_shadow(&self) -> Result<LockedFileGuard, crate::UserLibError> {
+        let path = self.shadow.as_ref();
+        match path {
+            Some(p) => LockedFileGuard::new(p),
+            None => Err(crate::UserLibError::FilesRequired),
+        }
+    }
+    pub fn lock_and_get_group(&self) -> Result<LockedFileGuard, crate::UserLibError> {
+        let path = self.group.as_ref();
+        match path {
+            Some(p) => LockedFileGuard::new(p),
+            None => Err(crate::UserLibError::FilesRequired),
+        }
+    }
+
+    pub fn lock_all_get(
+        &self,
+    ) -> Result<(LockedFileGuard, LockedFileGuard, LockedFileGuard), crate::UserLibError> {
+        let pwd = self.lock_and_get_passwd()?;
+        let shd = self.lock_and_get_shadow()?;
+        let grp = self.lock_and_get_group()?;
+        Ok((pwd, shd, grp))
+    }
+}
+
+#[derive(Debug)]
+pub struct LockedFileGuard {
+    lockfile: PathBuf,
+    path: PathBuf,
+    pub(crate) file: File,
+}
+
+#[derive(Debug)]
+struct TempLockFile {
+    tlf: PathBuf,
+}
+
+impl Drop for TempLockFile {
+    fn drop(&mut self) {
+        info!("removing temporary lockfile {}", self.tlf.to_str().unwrap());
+        std::fs::remove_file(&self.tlf).unwrap();
+    }
+}
+impl Deref for TempLockFile {
+    type Target = PathBuf;
+    fn deref(&self) -> &PathBuf {
+        &self.tlf
+    }
+}
+impl LockedFileGuard {
+    pub fn new(path: &PathBuf) -> Result<Self, crate::UserLibError> {
+        let locked = Self::try_to_lock_file(path);
+        match locked {
+            Ok((lockfile, file)) => Ok(Self {
+                lockfile,
+                path: path.to_owned(),
+                file,
+            }),
+            Err(e) => Err(e),
+        }
+    }
+
+    pub fn replace_contents(&mut self, new_content: String) -> Result<(), crate::UserLibError> {
+        self.file = match File::create(&self.path) {
+            Ok(file) => file,
+            Err(e) => return Err(("Failed to truncate file.".to_owned(), e).into()),
+        };
+        match self.file.write_all(&new_content.into_bytes()) {
+            Ok(_) => (),
+            Err(e) => return Err(("Could not write (all) users. ".to_owned(), e).into()),
+        };
+        let _ = self.file.write(b"\n");
+        Ok(())
+    }
+
+    pub fn append(&mut self, appendee: String) -> Result<(), crate::UserLibError> {
+        // Seek to the last character.
+        self.file.seek(SeekFrom::End(-1)).map_or_else(
+            |e| Err(format!("Failed to append to file {}", e)),
+            |_| Ok(()),
+        )?;
+        // Read the last character
+        let mut b = [0_u8; 1];
+        self.file.read_exact(&mut b)?;
+        // Verify it is '\n' else append '\n' so in any case the file ends with with a newline now
+        if &b != b"\n" {
+            //self.file.write_all(&b)?;
+            self.file.write_all(b"\n")?;
+        }
+        // write the new line.
+        self.file.write_all(&appendee.into_bytes()).map_or_else(
+            |e| Err(("Failed to append to file".to_owned(), e).into()),
+            Ok,
+        )
+    }
+
+    /// This function tries to lock a file in the way other passwd locking mechanisms work.
+    ///
+    /// * get the pid
+    /// * create the temporary lockfilepath "/etc/passwd.12397"
+    /// * create the lockfilepath "/etc/passwd.lock"
+    /// * open the temporary file
+    /// * write the pid to the tempfile
+    /// * try to make a link from the temporary file created to the lockfile
+    /// * ensure that the file has been linked successfully
+    ///
+    /// when the link could not be created:
+    ///
+    /// * Open the lockfile
+    /// * read the contents of the lockfile
+    /// * check if the lockfile contains a pid if not error out
+    /// * check if the containing pid is in a valid format. If not create a matching error
+    ///
+    /// not implemented yet:
+    ///
+    /// * test if this process could be killed. If so disclose the pid in the error.
+    /// * try to delete the lockfile as it is apparently not used by the process anmore. (cleanup)
+    /// * try to lock again now that the old logfile has been safely removed.
+    /// * remove the original file and only keep the lock hardlink
+    fn try_to_lock_file(path: &PathBuf) -> Result<(PathBuf, File), crate::UserLibError> {
+        info!("locking file {}", path.to_string_lossy());
+        let mut tempfilepath_const = path.clone();
+        // get the pid
+        let pid = std::process::id();
+        debug!("using pid {}", std::process::id());
+        // get the filename
+        let filename = tempfilepath_const.file_name().unwrap().to_owned();
+        // and the base path which is the base for tempfile and lockfile.
+        tempfilepath_const.pop();
+        let mut lockfilepath = tempfilepath_const.clone();
+        // push the filenames to the paths
+        tempfilepath_const.push(format!("{}.{}", filename.to_str().unwrap(), pid));
+        let tempfilepath = TempLockFile {
+            tlf: tempfilepath_const,
+        };
+        lockfilepath.push(format!("{}.lock", filename.to_str().unwrap()));
+        debug!(
+            "Lockfile paths: {:?} (temporary) {:?} (final)",
+            *tempfilepath, lockfilepath
+        );
+        // write the pid into the tempfile
+        {
+            let mut tempfile = File::create(&*tempfilepath).unwrap_or_else(|e| {
+                panic!("Failed to open {} error: {}", filename.to_str().unwrap(), e)
+            });
+            write!(tempfile, "{}", pid).or_else(|e| {
+                let error_msg = format!(
+                    "could not write to {} error {}",
+                    filename.to_string_lossy(),
+                    e
+                );
+                error!("{}", error_msg);
+                let err: crate::UserLibError = error_msg.into();
+                Err(err)
+            })?;
+        }
+
+        // try to make a hardlink from the lockfile to the tempfile
+        let linkresult = std::fs::hard_link(&*tempfilepath, &lockfilepath);
+        match linkresult {
+            Ok(()) => {
+                debug!("successfully locked");
+
+                // open the file
+                let resfile = OpenOptions::new().read(true).write(true).open(&path);
+                return match resfile {
+                    Ok(file) => Ok((lockfilepath, file)),
+                    Err(e) => {
+                        // failed to open the file undo the locks
+                        let _ = std::fs::remove_file(&lockfilepath);
+                        let ret: crate::UserLibError = format!(
+                            "Failed to open the file: {}, error: {}",
+                            path.to_str().unwrap(),
+                            e
+                        )
+                        .into();
+                        Err(ret)
+                    }
+                };
+            }
+            Err(e) => match e.kind() {
+                // analyze the error further
+                std::io::ErrorKind::AlreadyExists => {
+                    warn!("The file is already locked by another process! – testing the validity of the lock");
+                    {
+                        let mut lf = match File::open(&lockfilepath) {
+                            Ok(file) => file,
+                            Err(e) => {
+                                panic!("failed to open the lockfile: {}", e);
+                            }
+                        };
+                        let mut content = String::new();
+                        lf.read_to_string(&mut content)
+                            .unwrap_or_else(|e| panic!("failed to read the lockfile{}", e));
+
+                        let content = content.trim().trim_matches(char::from(0));
+                        let lock_pid = content.parse::<u32>();
+                        match lock_pid {
+                            Ok(pid) => {
+                                warn!(
+                                    "found a pid: {}, checking if this process is still running",
+                                    pid
+                                );
+                                error!("The file could not be locked");
+                                todo!("Validate the lock and delete the file if the process does not exist anymore");
+                                /*let sent = nix::sys::signal::kill(
+                                    nix::unistd::Pid::from_raw(pid as i32),
+                                    nix::sys::signal::Signal::from(0),
+                                );*/
+                            }
+                            Err(e) => error!(
+                                "existing lock file {} with an invalid PID '{}' Error: {}",
+                                lockfilepath.to_str().unwrap(),
+                                content,
+                                e
+                            ),
+                        }
+                    }
+                }
+
+                _ => {
+                    panic!("failed to lock the file: {}", e);
+                }
+            },
+        }
+        Err("was not able to lock!".into())
+    }
+}
+
+impl Drop for LockedFileGuard {
+    fn drop(&mut self) {
+        info!("removing lock");
+        std::fs::remove_file(&self.lockfile).unwrap();
+    }
+}

src/userlib/hashes.rs

@@ -0,0 +1,40 @@
+#[allow(unused_imports)]
+use log::{debug, error, info, trace, warn};
+pub struct SourceHash {
+    hashvalue: String,
+}
+
+impl SourceHash {
+    #[must_use]
+    pub fn new(src: &str) -> Self {
+        Self {
+            hashvalue: src.to_owned(),
+        }
+    }
+    #[must_use]
+    pub fn has_changed(&self, new: &str) -> bool {
+        trace!(
+            "Old and new lengths: {}, {}",
+            self.hashvalue.len(),
+            new.len()
+        );
+        !self.hashvalue.eq(new)
+    }
+}
+
+pub struct Hashes {
+    pub passwd: SourceHash,
+    pub shadow: SourceHash,
+    pub group: SourceHash,
+}
+
+impl Hashes {
+    #[must_use]
+    pub fn new(passwd: &str, shadow: &str, group: &str) -> Self {
+        Self {
+            passwd: SourceHash::new(passwd),
+            shadow: SourceHash::new(shadow),
+            group: SourceHash::new(group),
+        }
+    }
+}

src/userlib/mod.rs

@@ -0,0 +1,605 @@
+#![allow(clippy::non_ascii_literal)]
+
+pub mod files;
+pub mod hashes;
+
+use crate::{
+    api::{
+        CreateUserArgs, DeleteHome, DeleteUserArgs, GroupRead, UserDBRead, UserDBWrite, UserRead,
+    },
+    group::MembershipKind,
+    UserLibError,
+};
+#[allow(unused_imports)]
+use log::{debug, error, info, trace, warn};
+use std::collections::HashMap;
+use std::fs::File;
+use std::io::{BufReader, Read};
+
+pub type UserList = HashMap<String, crate::User>;
+
+pub struct UserDBLocal {
+    source_files: files::Files,
+    source_hashes: hashes::Hashes, // to detect changes
+    pub users: UserList,
+    pub groups: Vec<crate::Group>,
+}
+
+impl UserDBLocal {
+    /// Import the database from strings
+    #[must_use]
+    pub fn import_from_strings(
+        passwd_content: &str,
+        shadow_content: &str,
+        group_content: &str,
+    ) -> Self {
+        let shadow_entries: Vec<crate::Shadow> = string_to(shadow_content);
+        let mut users = user_vec_to_hashmap(string_to(passwd_content));
+        let mut groups = string_to(group_content);
+        shadow_to_users(&mut users, shadow_entries);
+        groups_to_users(&mut users, &mut groups);
+        Self {
+            source_files: files::Files {
+                passwd: None,
+                group: None,
+                shadow: None,
+            },
+            users,
+            groups,
+            source_hashes: hashes::Hashes::new(passwd_content, shadow_content, group_content),
+        }
+    }
+
+    /// Import the database from a [`Files`] struct
+    pub fn load_files(files: files::Files) -> Result<Self, crate::UserLibError> {
+        // Get the Strings for the files use an inner block to drop references after read.
+        let (my_passwd_lines, my_shadow_lines, my_group_lines) = {
+            let opened = files.lock_all_get();
+            let (locked_p, locked_s, locked_g) = opened.expect("failed to lock files!");
+            // read the files to strings
+            let p = file_to_string(&locked_p.file)?;
+            let s = file_to_string(&locked_s.file)?;
+            let g = file_to_string(&locked_g.file)?;
+            // return the strings to the outer scope and release the lock...
+            (p, s, g)
+        };
+
+        let mut users = user_vec_to_hashmap(string_to(&my_passwd_lines));
+        let passwds: Vec<crate::Shadow> = string_to(&my_shadow_lines);
+        let mut groups: Vec<crate::Group> = string_to(&my_group_lines);
+        shadow_to_users(&mut users, passwds);
+        groups_to_users(&mut users, &mut groups);
+        Ok(Self {
+            source_files: files,
+            users,
+            groups,
+            source_hashes: hashes::Hashes::new(&my_passwd_lines, &my_shadow_lines, &my_group_lines),
+        })
+    }
+    fn delete_from_passwd(
+        user: &crate::User,
+        passwd_file_content: &str,
+        locked_p: &mut files::LockedFileGuard,
+    ) -> Result<(), UserLibError> {
+        let modified_p = user.remove_in(passwd_file_content);
+
+        // write the new content to the file.
+        let ncont = locked_p.replace_contents(modified_p);
+        match ncont {
+            Ok(_) => Ok(()),
+            Err(e) => Err(format!("Failed to write the passwd database: {}", e).into()),
+        }
+    }
+
+    fn delete_from_shadow(
+        user: &crate::User,
+        shadow_file_content: &str,
+        locked_s: &mut files::LockedFileGuard,
+    ) -> Result<(), UserLibError> {
+        let shad = user.get_shadow();
+        match shad {
+            Some(shadow) => {
+                let modified_s = shadow.remove_in(shadow_file_content);
+                let ncont = locked_s.replace_contents(modified_s);
+                match ncont {
+                    Ok(_) => Ok(()),
+                    Err(e) => Err(format!(
+                        "Error during write to the database. \
+                    Please doublecheck as the shadowdatabase could be corrupted: {}",
+                        e,
+                    )
+                    .into()),
+                }
+            }
+            None => Ok(()),
+        }
+    }
+
+    fn delete_from_group(
+        group: &crate::Group,
+        group_file_content: &str,
+        locked_g: &mut files::LockedFileGuard,
+    ) -> Result<(), UserLibError> {
+        let modified_g = group.borrow().remove_in(group_file_content);
+        let replace_result = locked_g.replace_contents(modified_g);
+        match replace_result {
+            Ok(_) => Ok(()),
+            Err(e) => Err(format!(
+                "Error during write to the database. \
+            Please doublecheck as the groupdatabase could be corrupted: {}",
+                e,
+            )
+            .into()),
+        }
+    }
+
+    fn write_groups(&self, locked_g: &mut files::LockedFileGuard) -> Result<(), UserLibError> {
+        let content = self
+            .groups
+            .iter()
+            .map(|g| (g.borrow().to_string()))
+            .collect::<Vec<String>>()
+            .join("\n");
+        let replace_result = locked_g.replace_contents(content);
+        match replace_result {
+            Ok(_) => Ok(()),
+            Err(e) => Err(format!(
+                "Error during write to the database. \
+            Please doublecheck as the groupdatabase could be corrupted: {}",
+                e,
+            )
+            .into()),
+        }
+    }
+
+    fn delete_home(user: &crate::User) -> std::io::Result<()> {
+        if let Some(dir) = user.get_home_dir() {
+            std::fs::remove_dir_all(dir)
+        } else {
+            let error_msg = "Failed to remove the home directory! As the user did not have one.";
+            error!("{}", error_msg);
+            Err(std::io::Error::new(
+                std::io::ErrorKind::InvalidInput,
+                error_msg,
+            ))
+        }
+    }
+
+    fn delete_group_by_id(&mut self, gid: u32) {
+        self.groups
+            .retain(|g| g.borrow().get_gid().expect("groups have to have a gid") != gid);
+    }
+}
+
+impl UserDBWrite for UserDBLocal {
+    fn delete_user(&mut self, args: DeleteUserArgs) -> Result<crate::User, UserLibError> {
+        // try to get the user from the database
+        let user_opt = self.get_user_by_name(args.username);
+        let user = match user_opt {
+            Some(user) => user,
+            None => {
+                return Err(UserLibError::NotFound);
+            }
+        };
+
+        if self.source_files.is_virtual() {
+            warn!("There are no associated files working in dummy mode!");
+            let res = self.users.remove(args.username);
+            match res {
+                Some(u) => Ok(u),
+                None => Err(UserLibError::NotFound), // should not happen anymore as existence is checked.
+            }
+        } else {
+            let opened = self.source_files.lock_all_get();
+            let (mut locked_p, mut locked_s, mut locked_g) = opened.expect("failed to lock files!");
+
+            // read the files to strings
+            let passwd_file_content = file_to_string(&locked_p.file)?;
+            let shadow_file_content = file_to_string(&locked_s.file)?;
+            let group_file_content = file_to_string(&locked_g.file)?;
+
+            let src = &self.source_hashes;
+            if src.passwd.has_changed(&passwd_file_content)
+                | src.shadow.has_changed(&shadow_file_content)
+            {
+                error!("The source files have changed. Deleting the user could corrupt the userdatabase. Aborting!");
+                Err(format!("The userdatabase has been changed {}", args.username).into())
+            } else {
+                Self::delete_from_passwd(user, &passwd_file_content, &mut locked_p)?;
+                Self::delete_from_shadow(user, &shadow_file_content, &mut locked_s)?;
+                if args.delete_home == DeleteHome::Delete {
+                    Self::delete_home(user)?;
+                }
+                trace!("The users groups: {:#?}", user.get_groups());
+                // Iterate over the GIDs to avoid borrowing issues
+                let users_groups: Vec<(MembershipKind, u32)> = user
+                    .get_groups()
+                    .iter()
+                    .map(|(k, g)| (*k, g.borrow().get_gid().unwrap()))
+                    .collect();
+                for (kind, group) in users_groups {
+                    trace!("Woring on group: {:?} - {}", kind, group);
+                    match kind {
+                        crate::group::MembershipKind::Primary => {
+                            if self
+                                .get_group_by_id(group)
+                                .expect("The group does not exist")
+                                .borrow()
+                                .get_member_names()
+                                .expect("this group allways has a member")
+                                .len()
+                                == 1
+                            {
+                                trace!(
+                                    "Deleting group as the user to be deleted is the only member {}", self
+                                    .get_group_by_id(group)
+                                    .expect("The group does not exist")
+                                    .borrow()
+                                    .get_groupname().expect("a group has to have a name")
+                                );
+                                Self::delete_from_group(
+                                    self.get_group_by_id(group)
+                                        .expect("The group does not exist"),
+                                    &group_file_content,
+                                    &mut locked_g,
+                                )?;
+                                self.delete_group_by_id(group);
+                            } else {
+                                // remove the from the group instead of deleting the group if he was not the only user in its primary group.
+                                if let Some(group) = self.get_group_by_id(group) {
+                                    group
+                                        .borrow_mut()
+                                        .remove_member(MembershipKind::Primary, args.username)
+                                };
+                                self.write_groups(&mut locked_g)?;
+                                warn!(
+                                    "The primary group (GID: {}) was not empty and is thus not removed. Only the membership has been removed",
+                                    group
+                                );
+                            }
+                        }
+                        crate::group::MembershipKind::Member => {
+                            trace!("delete the membership in the group");
+                            if let Some(group) = self.get_group_by_id(group) {
+                                group
+                                    .borrow_mut()
+                                    .remove_member(MembershipKind::Member, args.username)
+                            };
+                            self.write_groups(&mut locked_g)?;
+                        }
+                    }
+                }
+                // Remove the user from the memory database(HashMap)
+                let res = self.users.remove(args.username);
+                match res {
+                    Some(u) => Ok(u),
+                    None => Err("Failed to remove the user from the internal HashMap".into()),
+                }
+            }
+        }
+    }
+
+    fn new_user(&mut self, args: CreateUserArgs) -> Result<&crate::User, crate::UserLibError> {
+        if self.users.contains_key(args.username) {
+            Err(format!("The username {} already exists! Aborting!", args.username).into())
+        } else {
+            let mut new_user = crate::User::default();
+            new_user.username(args.username.to_owned());
+            if self.users.contains_key(args.username) {
+                Err("Failed to create the user. A user with the same Name already exists".into())
+            } else {
+                let opened = self.source_files.lock_all_get();
+                let (mut locked_p, mut locked_s, mut _locked_g) =
+                    opened.expect("failed to lock files!");
+                //dbg!(&locked_p);
+                locked_p.append(format!("{}", new_user))?;
+                if let Some(shadow) = new_user.get_shadow() {
+                    info!("Adding shadow entry {}", shadow);
+                    locked_s.append(format!("{}", shadow))?;
+                } else {
+                    warn!("Omitting shadow entry!")
+                }
+                assert!(self
+                    .users
+                    .insert(args.username.to_owned(), new_user)
+                    .is_none());
+                self.users
+                    .get(args.username)
+                    .map_or_else(|| Err("User was not successfully added!".into()), Ok)
+            }
+        }
+    }
+
+    fn delete_group(&mut self, _group: &crate::Group) -> Result<(), crate::UserLibError> {
+        todo!()
+    }
+
+    fn new_group(&mut self) -> Result<&crate::Group, crate::UserLibError> {
+        todo!()
+    }
+}
+
+impl UserDBRead for UserDBLocal {
+    fn get_all_users(&self) -> Vec<&crate::User> {
+        let mut res: Vec<&crate::User> = self.users.iter().map(|(_, x)| x).collect();
+        res.sort();
+        res
+    }
+
+    fn get_user_by_name(&self, name: &str) -> Option<&crate::User> {
+        self.users.get(name)
+    }
+
+    fn get_user_by_id(&self, uid: u32) -> Option<&crate::User> {
+        // could probably be more efficient - on the other hand its no problem to loop a thousand users.
+        for user in self.users.values() {
+            if user.get_uid() == uid {
+                return Some(user);
+            }
+        }
+        None
+    }
+
+    fn get_all_groups(&self) -> Vec<crate::Group> {
+        self.groups.iter().map(std::clone::Clone::clone).collect()
+    }
+
+    fn get_group_by_name(&self, name: &str) -> Option<&crate::Group> {
+        for group in &self.groups {
+            if group.borrow().get_groupname()? == name {
+                return Some(group);
+            }
+        }
+        None
+    }
+
+    fn get_group_by_id(&self, id: u32) -> Option<&crate::Group> {
+        for group in &self.groups {
+            if group.borrow().get_gid()? == id {
+                return Some(group);
+            }
+        }
+        None
+    }
+}
+
+use crate::api::UserDBValidation;
+impl UserDBValidation for UserDBLocal {
+    fn is_uid_valid_and_free(&self, uid: u32) -> bool {
+        warn!("No valid check, only free check");
+        let free = self.users.iter().all(|(_, u)| u.get_uid() != uid);
+        free
+    }
+
+    fn is_username_valid_and_free(&self, name: &str) -> bool {
+        let valid = crate::user::passwd_fields::is_username_valid(name);
+        let free = self.get_user_by_name(name).is_none();
+        valid && free
+    }
+
+    fn is_gid_valid_and_free(&self, gid: u32) -> bool {
+        warn!("No valid check, only free check");
+        self.groups
+            .iter()
+            .all(|x| x.borrow().get_gid().unwrap() != gid)
+    }
+
+    fn is_groupname_valid_and_free(&self, name: &str) -> bool {
+        let valid = crate::group::is_groupname_valid(name);
+        let free = self
+            .groups
+            .iter()
+            .all(|x| x.borrow().get_groupname().unwrap() != name);
+        valid && free
+    }
+}
+
+/// Parse a file to a string
+fn file_to_string(file: &File) -> Result<String, crate::UserLibError> {
+    let mut reader = BufReader::new(file);
+    let mut lines = String::new();
+    let res = reader.read_to_string(&mut lines);
+    match res {
+        Ok(_) => Ok(lines),
+        Err(e) => Err(format!("failed to read the file: {:?}", e).into()),
+    }
+}
+
+fn groups_to_users<'a>(
+    users: &'a mut UserList,
+    groups: &'a mut [crate::Group],
+) -> &'a mut UserList {
+    // Populate the regular groups
+
+    for group in groups.iter() {
+        match group.borrow().get_member_names() {
+            Some(usernames) => {
+                for username in usernames {
+                    if let Some(user) = users.get_mut(username) {
+                        user.add_group(crate::group::MembershipKind::Member, group.clone());
+                    }
+                }
+            }
+            None => continue,
+        }
+    }
+
+    // Populate the primary membership
+    for user in users.values_mut() {
+        let gid = user.get_gid();
+        let grouplist: Vec<&crate::Group> = groups
+            .iter()
+            .filter(|g| g.borrow().get_gid().unwrap() == gid)
+            .collect();
+        if grouplist.len() == 1 {
+            let group = *grouplist.first().unwrap();
+            group.borrow_mut().append_user(
+                user.get_username()
+                    .expect("Users without username are not supported"),
+            );
+            user.add_group(crate::group::MembershipKind::Primary, group.clone());
+        } else {
+            error!(
+                "Somehow the group with gid {} was found {} times",
+                gid,
+                grouplist.len()
+            );
+        }
+    }
+    users
+}
+
+/// Merge the Shadow passwords into the users
+fn shadow_to_users(users: &mut UserList, shadow: Vec<crate::Shadow>) -> &mut UserList {
+    for pass in shadow {
+        let user = users
+            .get_mut(pass.get_username())
+            .unwrap_or_else(|| panic!("the user {} does not exist", pass.get_username()));
+        user.password = crate::Password::Shadow(pass);
+    }
+    users
+}
+
+/// Convert a `Vec<crate::User>` to a `UserList` (`HashMap<String, crate::User>`) where the username is used as key
+fn user_vec_to_hashmap(users: Vec<crate::User>) -> UserList {
+    users
+        .into_iter()
+        .map(|x| {
+            (
+                x.get_username()
+                    .expect("An empty username is not supported")
+                    .to_owned(),
+                x,
+            )
+        })
+        .collect()
+}
+
+/// Try to parse a String into some Object.
+///
+/// # Errors
+/// if the parsing failed a [`UserLibError::Message`](crate::userlib_error::UserLibError::Message) is returned containing a more detailed error message.
+pub trait NewFromString {
+    fn new_from_string(line: String, position: u32) -> Result<Self, crate::UserLibError>
+    where
+        Self: Sized;
+}
+
+/// A generic function that parses a string line by line and creates the appropriate `Vec<T>` requested by the type system.
+fn string_to<T>(source: &str) -> Vec<T>
+where
+    T: NewFromString,
+{
+    use std::convert::TryInto;
+    source
+        .lines()
+        .enumerate()
+        .filter_map(|(n, line)| {
+            if line.len() > 5 {
+                Some(
+                    T::new_from_string(
+                        line.to_owned(),
+                        n.try_into()
+                            .unwrap_or_else(|e| panic!("Failed to convert usize to u32 {}", e)),
+                    )
+                    .expect("failed to read lines"),
+                )
+            } else {
+                None
+            }
+        })
+        .collect()
+}
+
+#[test]
+fn test_creator_user_db_local() {
+    let data = UserDBLocal::import_from_strings("test:x:1002:1002:full Name,004,000342,001-2312,myemail@test.com:/home/test:/bin/test", "test:$6$u0Hh.9WKRF1Aeu4g$XqoDyL6Re/4ZLNQCGAXlNacxCxbdigexEqzFzkOVPV5Z1H23hlenjW8ZLgq6GQtFURYwenIFpo1c.r4aW9l5S/:18260:0:99999:7:::", "teste:x:1002:\nanother:x:1003:test");
+    assert_eq!(
+        data.users.get("test").unwrap().get_username().unwrap(),
+        "test"
+    );
+    for user in data.users.values() {
+        dbg!(user.get_groups());
+        let (member_group1, group1) = user.get_groups().first().unwrap();
+        let (member_group2, group2) = user.get_groups().get(1).unwrap();
+
+        assert_eq!(*member_group1, crate::group::MembershipKind::Member);
+        assert_eq!(group1.borrow().get_groupname(), Some("another"));
+        assert_eq!(*member_group2, crate::group::MembershipKind::Primary);
+        assert_eq!(group2.borrow().get_groupname(), Some("teste"));
+    }
+}
+
+#[test]
+fn test_parsing_local_database() {
+    use std::path::PathBuf;
+    // Parse the worldreadable user database ignore the shadow database as this would require root privileges.
+    let pwdfile = File::open(PathBuf::from("/etc/passwd")).unwrap();
+    let grpfile = File::open(PathBuf::from("/etc/group")).unwrap();
+    let my_passwd_lines = file_to_string(&pwdfile).unwrap();
+    let my_group_lines = file_to_string(&grpfile).unwrap();
+    let data = UserDBLocal::import_from_strings(&my_passwd_lines, "", &my_group_lines);
+    assert_eq!(
+        data.groups
+            .get(0)
+            .unwrap()
+            .borrow()
+            .get_groupname()
+            .unwrap(),
+        "root"
+    );
+}
+
+#[test]
+fn test_user_db_read_implementation() {
+    use std::path::PathBuf;
+    let pwdfile = File::open(PathBuf::from("/etc/passwd")).unwrap();
+    let grpfile = File::open(PathBuf::from("/etc/group")).unwrap();
+    let pass = file_to_string(&pwdfile).unwrap();
+    let group = file_to_string(&grpfile).unwrap();
+    let data = UserDBLocal::import_from_strings(&pass, "", &group);
+    // Usually there are more than 10 users
+    assert!(data.get_all_users().len() > 10);
+    assert!(data.get_user_by_name("root").is_some());
+    assert_eq!(data.get_user_by_name("root").unwrap().get_uid(), 0);
+    assert_eq!(
+        data.get_user_by_id(0).unwrap().get_username().unwrap(),
+        "root"
+    );
+    assert!(data.get_all_groups().len() > 10);
+    assert!(data.get_group_by_name("root").is_some());
+    assert_eq!(
+        data.get_group_by_name("root")
+            .unwrap()
+            .borrow()
+            .get_gid()
+            .unwrap(),
+        0
+    );
+    assert_eq!(
+        data.get_group_by_id(0)
+            .unwrap()
+            .borrow()
+            .get_groupname()
+            .unwrap(),
+        "root"
+    );
+    assert!(data.get_user_by_name("norealnameforsure").is_none());
+    assert!(data.get_group_by_name("norealgroupforsure").is_none());
+}
+
+#[test]
+fn test_user_db_write_implementation() {
+    use crate::api::DeleteUserArgs;
+    let mut data = UserDBLocal::import_from_strings("test:x:1001:1001:full Name,004,000342,001-2312,myemail@test.com:/home/test:/bin/test", "test:$6$u0Hh.9WKRF1Aeu4g$XqoDyL6Re/4ZLNQCGAXlNacxCxbdigexEqzFzkOVPV5Z1H23hlenjW8ZLgq6GQtFURYwenIFpo1c.r4aW9l5S/:18260:0:99999:7:::", "teste:x:1002:test,test");
+    let user = "test";
+
+    assert_eq!(data.get_all_users().len(), 1);
+    assert!(data
+        .delete_user(DeleteUserArgs::builder().username(user).build().unwrap())
+        .is_ok());
+    assert!(data
+        .delete_user(DeleteUserArgs::builder().username(user).build().unwrap())
+        .is_err());
+    assert_eq!(data.get_all_users().len(), 0);
+}

tests/create_user_test.rs

@@ -0,0 +1,123 @@
+extern crate test_bin;
+extern crate umanux;
+mod testfiles;
+
+#[test]
+fn test_create_user_function() {
+    use testfiles::Fixture;
+
+    use std::fs;
+    use umanux::api::UserDBWrite;
+    use umanux::api::UserRead;
+
+    let p = Fixture::copy("passwd");
+    let s = Fixture::copy("shadow");
+    let g = Fixture::copy("group");
+
+    let pf = fs::read_to_string(&p.path).unwrap();
+
+    let mf = umanux::Files {
+        passwd: Some(p.path.clone()),
+        shadow: Some(s.path),
+        group: Some(g.path),
+    };
+
+    let mut db = umanux::UserDBLocal::load_files(mf).unwrap();
+
+    let user_res: Result<&umanux::User, umanux::UserLibError> = db.new_user(
+        umanux::api::CreateUserArgs::builder()
+            .username("test2")
+            // .delete_home(umanux::api::DeleteHome::Delete)
+            .build()
+            .unwrap(),
+    );
+    let password_file_string = fs::read_to_string(&p.path).unwrap();
+    let shadow_file_string = fs::read_to_string(&p.path).unwrap();
+    assert_eq!(user_res.unwrap().get_username().unwrap(), "test2");
+    let pflines = pf.lines();
+    let pflines2 = password_file_string.lines();
+    for (l1, l2) in pflines.zip(pflines2) {
+        dbg!(l1, l2);
+        assert!(l1 == l2);
+    }
+    assert!(password_file_string
+        .lines()
+        .last()
+        .unwrap()
+        .starts_with("test2"));
+    assert!(shadow_file_string
+        .lines()
+        .last()
+        .unwrap()
+        .starts_with("test2"));
+}
+#[test]
+fn test_create_user_binary() {
+    use testfiles::Fixture;
+
+    use std::fs;
+
+    let p = Fixture::copy("passwd");
+    let s = Fixture::copy("shadow");
+    let g = Fixture::copy("group");
+
+    //dbg!(&p, &s, &g);
+
+    let passwd_string = fs::read_to_string(&p.path).unwrap();
+    let passwd_lines = passwd_string.lines();
+    let shadow_string = fs::read_to_string(&s.path).unwrap();
+    let shadow_lines = shadow_string.lines();
+
+    let out = test_bin::get_test_bin("create_user")
+        .args(&[
+            "testuser3",
+            "-p",
+            p.path.to_str().unwrap(),
+            "-s",
+            s.path.to_str().unwrap(),
+            "-g",
+            g.path.to_str().unwrap(),
+        ])
+        .output()
+        .expect("Failed to run the command");
+    println!(
+        "The output after running: {}",
+        String::from_utf8_lossy(&out.stdout)
+    );
+    println!(
+        "The error after running: {}",
+        String::from_utf8_lossy(&out.stderr)
+    );
+    assert_eq!(String::from_utf8_lossy(&out.stdout), "");
+    assert_eq!(String::from_utf8_lossy(&out.stderr), "");
+
+    let passwd_string_after = fs::read_to_string(&p.path).unwrap();
+    let passwd_lines_after = passwd_string_after.lines();
+    let shadow_string_after = fs::read_to_string(&s.path).unwrap();
+    let shadow_lines_after = shadow_string_after.lines();
+    for (l1, l2) in passwd_lines.zip(passwd_lines_after) {
+        //dbg!(l1, l2);
+        assert!(l1 == l2);
+    }
+    assert_eq!(
+        passwd_string_after
+            .lines()
+            .last()
+            .unwrap()
+            .starts_with("testuser3"),
+        true
+    );
+    //dbg!(&shadow_string_after);
+    for (l1, l2) in shadow_lines.zip(shadow_lines_after) {
+        //dbg!(l1, l2);
+        assert!(l1 == l2);
+    }
+    assert_eq!(
+        shadow_string_after
+            .lines()
+            .last()
+            .unwrap()
+            .starts_with("testuser3"),
+        true
+    );
+}

tests/delete_user_test.rs

@@ -0,0 +1,53 @@
+extern crate umanux;
+mod testfiles;
+
+#[test]
+fn test_delete_user_function() {
+    use testfiles::Fixture;
+
+    use std::fs;
+    use umanux::api::UserDBWrite;
+    use umanux::api::UserRead;
+
+    let p = Fixture::copy("passwd");
+    let s = Fixture::copy("shadow");
+    let g = Fixture::copy("group");
+
+    let pf = fs::read_to_string(&p.path).unwrap();
+
+    let mf = umanux::Files {
+        passwd: Some(p.path.clone()),
+        shadow: Some(s.path),
+        group: Some(g.path.clone()),
+    };
+
+    let mut db = umanux::UserDBLocal::load_files(mf).unwrap();
+
+    let user_res: Result<umanux::User, umanux::UserLibError> = db.delete_user(
+        umanux::api::DeleteUserArgs::builder()
+            .username("teste")
+            // .delete_home(umanux::api::DeleteHome::Delete)
+            .build()
+            .unwrap(),
+    );
+    let pf2 = fs::read_to_string(&p.path).unwrap();
+    assert_eq!(user_res.unwrap().get_username().unwrap(), "teste");
+    let pflines = pf.lines();
+    let pflines2 = pf2.lines();
+    for (l1, l2) in pflines.zip(pflines2.clone()) {
+        if l1 != l2 {
+            assert!(l1.starts_with("teste"));
+            assert!(l2.starts_with("bergfried"));
+            break;
+        }
+    }
+    for line in pflines2 {
+        assert!(!line.starts_with("teste"))
+    }
+    let groupfile2 = fs::read_to_string(&g.path).unwrap();
+    let groupfilelines2 = groupfile2.lines();
+    for line in groupfilelines2 {
+        println!("{}", &line);
+        assert!(!line.ends_with("teste"))
+    }
+}

tests/fixtures/group

@@ -0,0 +1,93 @@
+root:x:0:
+bin:x:1:
+daemon:x:2:
+sys:x:3:
+adm:x:4:
+tty:x:5:
+disk:x:6:
+lp:x:7:
+mem:x:8:
+kmem:x:9:
+wheel:x:10:dietrich
+cdrom:x:11:
+mail:x:12:
+man:x:15:
+dialout:x:18:dietrich
+floppy:x:19:
+games:x:20:
+tape:x:33:
+video:x:39:
+ftp:x:50:
+lock:x:54:dietrich
+audio:x:63:
+users:x:100:
+nobody:x:65534:
+utmp:x:22:
+utempter:x:35:
+input:x:999:
+kvm:x:36:qemu
+render:x:998:
+systemd-journal:x:190:
+systemd-coredump:x:997:
+systemd-network:x:192:
+systemd-resolve:x:193:
+dbus:x:81:
+systemd-timesync:x:996:
+tss:x:59:clevis
+dip:x:40:
+printadmin:x:995:
+gluster:x:994:
+qemu:x:107:
+nm-openconnect:x:993:
+usbmuxd:x:113:
+geoclue:x:992:
+polkitd:x:991:
+rtkit:x:172:
+pulse-access:x:990:
+pulse-rt:x:989:
+pulse:x:171:
+chrony:x:988:
+avahi:x:70:
+pipewire:x:987:
+dnsmasq:x:986:
+saslauth:x:76:
+radvd:x:75:
+rpc:x:32:
+ssh_keys:x:985:
+openvpn:x:984:
+nm-openvpn:x:983:
+libvirt:x:982:dietrich
+unbound:x:981:
+brlapi:x:980:
+apache:x:48:
+colord:x:979:
+rpcuser:x:29:
+abrt:x:173:
+flatpak:x:978:
+gdm:x:42:
+gnome-initial-setup:x:977:
+sshd:x:74:
+slocate:x:21:
+vboxsf:x:976:
+tcpdump:x:72:
+wbpriv:x:88:
+clevis:x:975:
+cockpit-ws:x:974:
+libvirtdbus:x:973:
+setroubleshoot:x:972:
+mysql:x:27:
+firebird:x:971:
+cockpit-wsinstance:x:970:
+pbuilder:x:969:
+teste:x:1002:test,teste
+testnewgroup:x:1015:teste
+hausle:x:1018:dietrich
+bergfried:x:1009:
+t1:x:1019:
+t2:x:1020:
+docker:x:968:
+jackuser:x:967:
+akmods:x:966:
+mock:x:135:
+rtlsdr:x:965:
+Debian-exim:x:128:

tests/fixtures/passwd

@@ -0,0 +1,60 @@
+root:x:0:0:root:/root:/bin/bash
+bin:x:1:1:bin:/bin:/sbin/nologin
+daemon:x:2:2:daemon:/sbin:/sbin/nologin
+adm:x:3:4:adm:/var/adm:/sbin/nologin
+lp:x:4:7:lp:/var/spool/lpd:/sbin/nologin
+sync:x:5:0:sync:/sbin:/bin/sync
+shutdown:x:6:0:shutdown:/sbin:/sbin/shutdown
+halt:x:7:0:halt:/sbin:/sbin/halt
+mail:x:8:12:mail:/var/spool/mail:/sbin/nologin
+operator:x:11:0:operator:/root:/sbin/nologin
+games:x:12:100:games:/usr/games:/sbin/nologin
+ftp:x:14:50:FTP User:/var/ftp:/sbin/nologin
+nobody:x:65534:65534:Kernel Overflow User:/:/sbin/nologin
+systemd-coredump:x:999:997:systemd Core Dumper:/:/sbin/nologin
+systemd-network:x:192:192:systemd Network Management:/:/sbin/nologin
+systemd-resolve:x:193:193:systemd Resolver:/:/sbin/nologin
+dbus:x:81:81:System message bus:/:/sbin/nologin
+systemd-timesync:x:998:996:systemd Time Synchronization:/:/sbin/nologin
+tss:x:59:59:Account used by the trousers package to sandbox the tcsd daemon:/dev/null:/sbin/nologin
+gluster:x:997:994:GlusterFS daemons:/run/gluster:/sbin/nologin
+qemu:x:107:107:qemu user:/:/sbin/nologin
+nm-openconnect:x:996:993:NetworkManager user for OpenConnect:/:/sbin/nologin
+usbmuxd:x:113:113:usbmuxd user:/:/sbin/nologin
+geoclue:x:995:992:User for geoclue:/var/lib/geoclue:/sbin/nologin
+polkitd:x:994:991:User for polkitd:/:/sbin/nologin
+rtkit:x:172:172:RealtimeKit:/proc:/sbin/nologin
+pulse:x:171:171:PulseAudio System Daemon:/var/run/pulse:/sbin/nologin
+chrony:x:993:988::/var/lib/chrony:/sbin/nologin
+avahi:x:70:70:Avahi mDNS/DNS-SD Stack:/var/run/avahi-daemon:/sbin/nologin
+pipewire:x:992:987:PipeWire System Daemon:/var/run/pipewire:/sbin/nologin
+dnsmasq:x:986:986:Dnsmasq DHCP and DNS server:/var/lib/dnsmasq:/sbin/nologin
+saslauth:x:985:76:Saslauthd user:/run/saslauthd:/sbin/nologin
+radvd:x:75:75:radvd user:/:/sbin/nologin
+rpc:x:32:32:Rpcbind Daemon:/var/lib/rpcbind:/sbin/nologin
+openvpn:x:984:984:OpenVPN:/etc/openvpn:/sbin/nologin
+nm-openvpn:x:983:983:Default user for running openvpn spawned by NetworkManager:/:/sbin/nologin
+unbound:x:982:981:Unbound DNS resolver:/etc/unbound:/sbin/nologin
+apache:x:48:48:Apache:/usr/share/httpd:/sbin/nologin
+colord:x:981:979:User for colord:/var/lib/colord:/sbin/nologin
+rpcuser:x:29:29:RPC Service User:/var/lib/nfs:/sbin/nologin
+abrt:x:173:173::/etc/abrt:/sbin/nologin
+flatpak:x:980:978:User for flatpak system helper:/:/sbin/nologin
+gdm:x:42:42::/var/lib/gdm:/sbin/nologin
+gnome-initial-setup:x:979:977::/run/gnome-initial-setup/:/sbin/nologin
+sshd:x:74:74:Privilege-separated SSH:/var/empty/sshd:/sbin/nologin
+vboxadd:x:978:1::/var/run/vboxadd:/sbin/nologin
+tcpdump:x:72:72::/:/sbin/nologin
+clevis:x:977:975:Clevis Decryption Framework unprivileged user:/var/cache/clevis:/sbin/nologin
+cockpit-ws:x:976:974:User for cockpit-ws:/nonexisting:/sbin/nologin
+libvirtdbus:x:975:973:Libvirt D-Bus bridge:/:/sbin/nologin
+setroubleshoot:x:974:972::/var/lib/setroubleshoot:/sbin/nologin
+mysql:x:27:27:MySQL Server:/var/lib/mysql:/sbin/nologin
+firebird:x:973:971::/:/bin/nologin
+cockpit-wsinstance:x:972:970:User for cockpit-ws instances:/nonexisting:/sbin/nologin
+pbuilder:x:971:969:pbuilder:/var/run/pbuilder:/sbin/nologin
+test:x:1001:1015:Long,007,1499990,1999201,AKK:/home/test:/bin/bash
+teste:x:1002:1002::/home/teste:/bin/bash
+bergfried:x:1009:1009:Bergfried Freiberg,,,,:/home/bergfried:/bin/bash
+akmods:x:970:966:User is used by akmods to build akmod packages:/var/cache/akmods/:/sbin/nologin
+Debian-exim:x:123:128::/var/spool/exim4:/usr/sbin/nologin

tests/fixtures/shadow

@@ -0,0 +1,60 @@
+root:$6$I4MRB1rzlIft7qiw$2i0OBungWyGBxXbcxbHNKfeaXKRQBEksxK8o3Zvb8VQKuDOSCaLjh1p6C1yfY.z/BCX0dzozj6l3F67QW1X8b.:18260:0:99999:7:::
+bin:*:17995:0:99999:7:::
+daemon:*:17995:0:99999:7:::
+adm:*:17995:0:99999:7:::
+lp:*:17995:0:99999:7:::
+sync:*:17995:0:99999:7:::
+shutdown:*:17995:0:99999:7:::
+halt:*:17995:0:99999:7:::
+mail:*:17995:0:99999:7:::
+operator:*:17995:0:99999:7:::
+games:*:17995:0:99999:7:::
+ftp:*:17995:0:99999:7:::
+nobody:*:17995:0:99999:7:::
+systemd-coredump:!!:18107::::::
+systemd-network:!!:18107::::::
+systemd-resolve:!!:18107::::::
+dbus:!!:18107::::::
+systemd-timesync:!!:18107::::::
+tss:!!:18107::::::
+gluster:!!:18107::::::
+qemu:!!:18107::::::
+nm-openconnect:!!:18107::::::
+usbmuxd:!!:18107::::::
+geoclue:!!:18107::::::
+polkitd:!!:18107::::::
+rtkit:!!:18107::::::
+pulse:!!:18107::::::
+chrony:!!:18107::::::
+avahi:!!:18107::::::
+pipewire:!!:18107::::::
+dnsmasq:!!:18107::::::
+saslauth:!!:18107::::::
+radvd:!!:18107::::::
+rpc:!!:18107:0:99999:7:::
+openvpn:!!:18107::::::
+nm-openvpn:!!:18107::::::
+unbound:!!:18107::::::
+apache:!!:18107::::::
+colord:!!:18107::::::
+rpcuser:!!:18107::::::
+abrt:!!:18107::::::
+flatpak:!!:18107::::::
+gdm:!!:18107::::::
+gnome-initial-setup:!!:18107::::::
+sshd:!!:18107::::::
+vboxadd:!!:18107::::::
+tcpdump:!!:18107::::::
+clevis:!!:18113::::::
+cockpit-ws:!!:18113::::::
+libvirtdbus:!!:18113::::::
+setroubleshoot:!!:18113::::::
+mysql:!!:18137::::::
+firebird:!!:18140::::::
+cockpit-wsinstance:!!:18196::::::
+pbuilder:!!:18198::::::
+test:$6$K3iBIIJwfJjolbIV$AaDjW1kvaeYl8KAqAkvXMTWloQV2VsB8a33PHYItRPdETtYGKP2T2n6HjUUuXUZFPxLdnJyB8cWlpPCl1x/VP0:18574:0:99999:7:::
+teste:$6$u0Hh.9WKRF1Aeu4g$XqoDyL6Re/4ZLNQCGAXlNacxCxbdigexEqzFzkOVPV5Z1H23hlenjW8ZLgq6GQtFURYwenIFpo1c.r4aW9l5S/:18574:0:99999:7:::
+bergfried:$6$dzc1lAZo7XaWwFx9$MpUJtzD9WFJhgt.5zVtgP6mGjFldNCZ02Pp9S9Y4XTV16fMUuN/0vi5Xs4BH2T0G6EL2gS/gAHRnsyvY4aVi31:18574:0:99999:7:::
+akmods:!!:18395::::::
+Debian-exim:!:18574:0:99999:7:::

tests/testfiles.rs

@@ -0,0 +1,49 @@
+use std::{env, path::Path};
+use std::{fs, path::PathBuf};
+
+use tempfile::TempDir;
+
+use std::ops::Deref;
+
+#[derive(Debug)]
+pub struct Fixture {
+    pub path: PathBuf,
+    pub source: PathBuf,
+    _tempdir: TempDir,
+}
+
+impl Fixture {
+    #[must_use]
+    pub fn blank(fixture_filename: &str) -> Self {
+        // First, figure out the right file in `tests/fixtures/`:
+        let root_dir = &env::var("CARGO_MANIFEST_DIR").expect("$CARGO_MANIFEST_DIR");
+        let mut source = PathBuf::from(root_dir);
+        source.push("tests/fixtures");
+        source.push(&fixture_filename);
+
+        // The "real" path of the file is going to be under a temporary directory:
+        let tempdir = tempfile::tempdir().unwrap();
+        let mut path = PathBuf::from(&tempdir.path());
+        path.push(&fixture_filename);
+
+        Self {
+            _tempdir: tempdir,
+            source,
+            path,
+        }
+    }
+    #[must_use]
+    pub fn copy(fixture_filename: &str) -> Self {
+        let fixture = Self::blank(fixture_filename);
+        fs::copy(&fixture.source, &fixture.path).unwrap();
+        fixture
+    }
+}
+
+impl Deref for Fixture {
+    type Target = Path;
+
+    fn deref(&self) -> &Self::Target {
+        &self.path
+    }
+}