feature: add readonly mode (#1861)

* init

* Fixed code smells

* Updated documentation as per feedback

docs/content/configuration/command-line-options.md

@@ -33,6 +33,7 @@ see information on these options by running `btm -h`, or run `btm --help` to dis
 | `-S, --case_sensitive`      | Enables case sensitivity by default when searching.                                    |
 | `-u, --current_usage`       | Calculates process CPU usage as a percentage of current usage rather than total usage. |
 | `--disable_advanced_kill`   | Hides additional stopping options on Unix-like systems.                                |
+| `--read_only`               | Prevents performing any actions that affect the system (e.g. stopping processes).      |
 | `--get_threads`             | Also gather process thread information.                                                |
 | `-g, --group_processes`     | Groups processes with the same name by default. No effect if `--tree` is set.          |
 | `--hide_k_threads`          | Hide kernel threads by default.                                                        |

docs/content/configuration/config-file/flags.md

@@ -41,6 +41,7 @@ each time:
 | `show_table_scroll_position` | Boolean                                                                                                            | Shows the scroll position tracker in table widgets.                                                                          |
 | `process_command`            | Boolean                                                                                                            | Show processes as their commands by default.                                                                                 |
 | `disable_advanced_kill`      | Boolean                                                                                                            | Disable being able to send signals to processes on supported Unix-like systems. Only available on Linux, macOS, and FreeBSD. |
+| `read_only`                  | Boolean                                                                                                            | Prevents performing any actions that affect the system (e.g. stopping processes).                                           |
 | `network_use_binary_prefix`  | Boolean                                                                                                            | Displays the network widget with binary prefixes.                                                                            |
 | `network_use_bytes`          | Boolean                                                                                                            | Displays the network widget using bytes.                                                                                     |
 | `network_use_log`            | Boolean                                                                                                            | Displays the network widget with a log scale.                                                                                |

sample_configs/default_config.toml

@@ -106,6 +106,9 @@
 # Hides advanced options to stop a process on Unix-like systems.
 #disable_advanced_kill = false
 
+# Prevents performing any actions that affect the system (e.g. stopping processes).
+#read_only = false
+
 # Hides the kernel threads
 #hide_k_threads = false
 

src/app.rs

@@ -57,6 +57,7 @@ pub struct AppConfigFields {
     pub show_table_scroll_position: bool,
     #[cfg(any(target_os = "linux", target_os = "macos", target_os = "freebsd"))]
     pub is_advanced_kill: bool,
+    pub is_read_only: bool,
     #[cfg(target_os = "linux")]
     pub hide_k_threads: bool,
     #[cfg(feature = "zfs")]
@@ -991,6 +992,10 @@ impl App {
     ///
     /// TODO: This ideally gets abstracted out into a separate widget.
     pub(crate) fn kill_current_process(&mut self) {
+        if self.app_config_fields.is_read_only {
+            return;
+        }
+
         if let Some(pws) = self
             .states
             .proc_state

src/constants.rs

@@ -352,6 +352,9 @@ pub(crate) const CONFIG_TEXT: &str = r#"# This is a default config file for bott
 # Hides advanced options to stop a process on Unix-like systems.
 #disable_advanced_kill = false
 
+# Prevents performing any actions that affect the system (e.g. stopping processes).
+#read_only = false
+
 # Hides the kernel threads
 #hide_k_threads = false
 

src/options.rs

@@ -242,6 +242,7 @@ pub(crate) fn init_app(args: BottomArgs, config: Config) -> Result<(App, BottomL
     let is_default_command = is_flag_enabled!(process_command, args.process, config);
     #[cfg(any(target_os = "linux", target_os = "macos", target_os = "freebsd"))]
     let is_advanced_kill = !(is_flag_enabled!(disable_advanced_kill, args.process, config));
+    let is_read_only = is_flag_enabled!(read_only, args.process, config);
     #[cfg(target_os = "linux")]
     let hide_k_threads = is_flag_enabled!(hide_k_threads, args.process, config);
 
@@ -321,6 +322,7 @@ pub(crate) fn init_app(args: BottomArgs, config: Config) -> Result<(App, BottomL
         ),
         #[cfg(any(target_os = "linux", target_os = "macos", target_os = "freebsd"))]
         is_advanced_kill,
+        is_read_only,
         #[cfg(target_os = "linux")]
         hide_k_threads,
         memory_legend_position,

src/options/args.rs

@@ -324,6 +324,16 @@ pub struct ProcessArgs {
     )]
     pub disable_advanced_kill: bool,
 
+    #[arg(
+        long,
+        action = ArgAction::SetTrue,
+        help = "Prevents performing any actions that affect the system.",
+        long_help = "Prevents performing any actions that affect the system. Disables operations such as stopping or sending signals \
+                 to processes.",
+        alias = "read-only"
+    )]
+    pub read_only: bool,
+
     #[cfg(target_os = "linux")]
     #[arg(
         long,

src/options/config/flags.rs

@@ -40,6 +40,7 @@ pub(crate) struct GeneralConfig {
     pub(crate) process_command: Option<bool>,
     // #[cfg(any(target_os = "linux", target_os = "macos", target_os = "freebsd"))]
     pub(crate) disable_advanced_kill: Option<bool>, // This does nothing on Windows, but we leave it enabled to make the config file consistent across platforms.
+    pub(crate) read_only: Option<bool>,
     // #[cfg(target_os = "linux")]
     pub(crate) hide_k_threads: Option<bool>,
     // #[cfg(feature = "zfs")]