help and version flags

Cargo.lock

@@ -34,7 +34,7 @@ checksum = "baf1de4339761588bc0619e3cbc0120ee582ebb74b53b4efbf79117bd2da40fd"
 
 [[package]]
 name = "crab"
-version = "0.0.1"
+version = "0.0.3"
 dependencies = [
  "exec",
  "nix",

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "crab"
-version = "0.0.1"
+version = "0.0.3"
 edition = "2021"
 
 [dependencies]

src/flags.rs

@@ -0,0 +1,58 @@
+pub struct Flags {
+  pub help: bool,
+  pub version: bool,
+  pub dont_persist: bool,
+  pub arg_count: usize
+}
+
+pub fn parse(args: &[String]) -> Flags {
+  let mut flags = Flags { 
+    help: false, 
+    version: false,
+    dont_persist: false, 
+    arg_count: 0 
+  };
+  for arg in args {
+    if !is_arg(&arg) { break; }
+    flags.arg_count += 1;
+    if arg.starts_with("--") {
+      let flag = &arg[2..];
+      check_flag(&flag, &mut flags);
+    } else {
+      let flag = &arg[1..];
+      for char in flag.chars() {
+        check_flag(&char.to_string(), &mut flags);
+      }
+    }
+  }
+  flags
+}
+
+fn is_arg(arg: &str) -> bool {
+  return arg.starts_with("-");
+}
+
+const HELP_FLAG:              &str = "help h";
+const VERSION_FLAG:           &str = "version v";
+const DONT_PERSIST:           &str = "d";
+
+fn check_flag(arg: &str, flags: &mut Flags) {
+  if has_flag_set(&arg, HELP_FLAG) {
+    flags.help = true
+  }
+  if has_flag_set(&arg, VERSION_FLAG) {
+    flags.version = true
+  }
+  if has_flag_set(&arg, DONT_PERSIST) {
+    flags.dont_persist = true
+  }
+}
+
+fn has_flag_set(arg: &str, check: &str) -> bool {
+  for check_arg in check.split(" ") {
+    if check_arg == arg {
+      return true
+    }
+  }
+  return false
+}

src/help.rs

@@ -0,0 +1,11 @@
+pub fn help() {
+  let help = 
+"Usage:
+    crab [-d] command [args]
+
+Options:
+    -v --version    Get the current version of the package
+    -h --help       Generates the crab help message
+    -d              If your user is set to persist, dont save persistance";
+  println!("{}", help);
+}

src/main.rs

@@ -1,30 +1,35 @@
-use std::fs;
-use std::os::linux::fs::MetadataExt;
-use std::{env, os::unix::prelude::PermissionsExt};
+use std::env;
 use std::process::ExitCode;
-use std::time::SystemTime;
 use pwd::Passwd;
 use nix::unistd;
-use serde_json::Value;
 
 extern crate time;
 
-const ERROR_ARGS:           u8 = 1;
+// const ERROR_COMMAND:           u8 = 1;
 const ERROR_CONFIG:         u8 = 2;
 const ERROR_NO_USER:        u8 = 3;
 const ERROR_NOT_AUTHORIZED: u8 = 4;
 const ERROR_AUTH_FAILED:    u8 = 5;
 const ERROR_RUN_ROOT:       u8 = 6;
-const SUCCESS:              u8 = 0;
-
-const PERSIST_TIME:         u64 = 60 * 3;
 
+mod persist;
+mod flags;
+mod help;
 
 fn main() -> ExitCode {
     let args: Vec<String> = env::args().collect();
-    if args.len() < 2 {
-        println!("usage: crab command [args]");
-        return ExitCode::from(ERROR_ARGS);
+    let flags = flags::parse(&args[1..]);
+    if flags.version {
+        println!("crab version 0.0.3");
+        return ExitCode::SUCCESS;
+    }
+    if flags.help {
+        help::help();
+        return ExitCode::SUCCESS;
+    }
+    if args.len() - flags.arg_count < 2 {
+        println!("usage: crab [-d] command [args]");
+        return ExitCode::SUCCESS;
     }
     let config = match config("/etc/crab.conf") {
         Some(data) => data,
@@ -38,7 +43,7 @@ fn main() -> ExitCode {
         }
     };
     let persist = match allowed(&config, &user.name) {
-        Some(data) => data,
+        Some(data) => data && !flags.dont_persist,
         None => {
             eprintln!("Operation Not Permitted.");
             return ExitCode::from(ERROR_NOT_AUTHORIZED);
@@ -54,11 +59,12 @@ fn main() -> ExitCode {
         eprintln!("Failed to set root permissions");
         return ExitCode::from(ERROR_RUN_ROOT);
     };
+    let start = 1 + flags.arg_count;
+    let err = exec::execvp(&args[start], &args[start..]);
     
-    let err = exec::execvp(&args[1], &args[1..]);
-    println!("Error: {}", err);
+    eprintln!("{}", err);
     
-    ExitCode::from(SUCCESS)
+    ExitCode::SUCCESS
 }
 
 struct Config {
@@ -66,7 +72,7 @@ struct Config {
 }
 
 fn validate(user: &str, persist: bool) -> bool {
-    if persist && get_persist(user) {
+    if persist && persist::get_persist(user) {
         return true;
     }
     let input = match rpassword::prompt_password(format!("crab ({}) password: ", user)) {
@@ -82,7 +88,7 @@ fn validate(user: &str, persist: bool) -> bool {
         return false;
     }
     if persist {
-        set_persist(user);
+        persist::set_persist(user);
     }
     return true;
 }
@@ -127,96 +133,3 @@ fn config(path: &str) -> Option<Config> {
     }
     Some(Config{users})
 }
-
-fn get_terminal_process() -> Option<i32> {
-    let id: i32 = match std::process::id().try_into() {
-        Ok(data) => data,
-        Err(_) => return None
-    };
-    let stat = match procinfo::pid::stat(id) {
-        Ok(data) => data,
-        Err(_) => return None
-    };
-    Some(stat.session)
-}
-
-fn is_file_root_only(id: &i32) -> bool {
-    let metadata = match std::fs::metadata(path(&id)) {
-        Ok(data) => data,
-        Err(e) => {
-            if let Some(err) = e.raw_os_error() {
-                return err == 2;
-            }
-            return true
-        }
-    };
-    let perms = metadata.permissions();
-    return perms.mode() == 33200 && metadata.st_uid() == 0 && metadata.st_gid() == 0;
-}
-
-fn get_terminal_config() -> Option<Value> {
-    let id = match get_terminal_process() {
-        Some(data) => data,
-        None => return None
-    };
-    if !is_file_root_only(&id) {
-        return None;
-    }
-    let data = match std::fs::read_to_string(path(&id)) {
-        Ok(data) => data,
-        Err(_) => "{}".to_string()
-    };
-    let json: Value = match serde_json::from_str(&data) {
-        Ok(data) => data,
-        Err(_) => return None
-    };
-    Some(json)
-}
-
-fn write_terminal_config(id: &i32, data: &str) -> Result<(), Box<dyn std::error::Error>> {
-    std::fs::write(path(&id), data)?;
-    unistd::chown(std::path::Path::new(&path(&id)), Some(unistd::Uid::from(0)), Some(unistd::Gid::from(0)))?;
-    let metadata = std::fs::metadata(path(&id))?;
-    let mut perms = metadata.permissions();
-    perms.set_mode(0o660);
-    fs::set_permissions(path(&id), perms)?;
-    Ok(())
-}
-
-fn get_persist(user: &str) -> bool {
-    let json = match get_terminal_config() {
-        Some(data) => data,
-        None => return false
-    };
-    let timestamp = match json[user].as_u64() {
-        Some(data) => data,
-        None => return false
-    };
-    return now() - timestamp < PERSIST_TIME;
-}
-
-fn set_persist(user: &str) {
-    let mut json = match get_terminal_config() {
-        Some(data) => data,
-        None => return
-    };
-    json[user] = Value::from(now());
-    let id = match get_terminal_process() {
-        Some(data) => data,
-        None => return
-    };
-    match write_terminal_config(&id, &json.to_string()) {
-        Ok(_) => {},
-        Err(e) => {
-            eprintln!("Internal Error: {}", e)
-        }
-    };
-}
-
-fn now() -> u64 {
-    return SystemTime::now().duration_since(SystemTime::UNIX_EPOCH).unwrap().as_secs();
-}
-
-fn path(id: &i32) -> String {
-    return format!("/tmp/crab-{}", id);
-}

src/persist.rs

@@ -0,0 +1,101 @@
+use std::fs;
+use std::os::linux::fs::MetadataExt;
+use std::os::unix::prelude::PermissionsExt;
+use std::time::SystemTime;
+use nix::unistd;
+use serde_json::Value;
+
+const PERSIST_TIME:         u64 = 60 * 3;
+
+pub fn get_persist(user: &str) -> bool {
+  let json = match get_terminal_config() {
+      Some(data) => data,
+      None => return false
+  };
+  let timestamp = match json[user].as_u64() {
+      Some(data) => data,
+      None => return false
+  };
+  return now() - timestamp < PERSIST_TIME;
+}
+
+pub fn set_persist(user: &str) {
+  let mut json = match get_terminal_config() {
+      Some(data) => data,
+      None => return
+  };
+  json[user] = Value::from(now());
+  let id = match get_terminal_process() {
+      Some(data) => data,
+      None => return
+  };
+  match write_terminal_config(&id, &json.to_string()) {
+      Ok(_) => {},
+      Err(e) => {
+          eprintln!("Internal Error: {}", e)
+      }
+  };
+}
+
+fn get_terminal_process() -> Option<i32> {
+  let id: i32 = match std::process::id().try_into() {
+      Ok(data) => data,
+      Err(_) => return None
+  };
+  let stat = match procinfo::pid::stat(id) {
+      Ok(data) => data,
+      Err(_) => return None
+  };
+  Some(stat.session)
+}
+
+fn is_file_root_only(id: &i32) -> bool {
+  let metadata = match std::fs::metadata(path(&id)) {
+      Ok(data) => data,
+      Err(e) => {
+          if let Some(err) = e.raw_os_error() {
+              return err == 2;
+          }
+          return true
+      }
+  };
+  let perms = metadata.permissions();
+  return perms.mode() == 33200 && metadata.st_uid() == 0 && metadata.st_gid() == 0;
+}
+
+fn get_terminal_config() -> Option<Value> {
+  let id = match get_terminal_process() {
+      Some(data) => data,
+      None => return None
+  };
+  if !is_file_root_only(&id) {
+      return None;
+  }
+  let data = match std::fs::read_to_string(path(&id)) {
+      Ok(data) => data,
+      Err(_) => "{}".to_string()
+  };
+  let json: Value = match serde_json::from_str(&data) {
+      Ok(data) => data,
+      Err(_) => return None
+  };
+  Some(json)
+}
+
+fn write_terminal_config(id: &i32, data: &str) -> Result<(), Box<dyn std::error::Error>> {
+  std::fs::write(path(&id), data)?;
+  unistd::chown(std::path::Path::new(&path(&id)), Some(unistd::Uid::from(0)), Some(unistd::Gid::from(0)))?;
+  let metadata = std::fs::metadata(path(&id))?;
+  let mut perms = metadata.permissions();
+  perms.set_mode(0o660);
+  fs::set_permissions(path(&id), perms)?;
+  Ok(())
+}
+
+fn now() -> u64 {
+  return SystemTime::now().duration_since(SystemTime::UNIX_EPOCH).unwrap().as_secs();
+}
+
+fn path(id: &i32) -> String {
+  return format!("/tmp/crab-{}", id);
+}