Add Microphone Input Level applet

[Skatterbrainz]

A Cinnamon panel applet for controlling microphone input volume and mute status.

Features:

• Real-time volume display on panel
• Volume slider (0-100%)
• Mute/unmute toggle
• Dynamic icon that changes based on volume level and mute status
• Uses PulseAudio (pactl) for audio control
• Updates automatically every second

Tested on Cinnamon 6.6.6 with Linux Mint 22.3

[github-actions]

Best-practices scanner

This is a regex-based check for API usage that can pose security, performance or
maintainability issues, or that may already be provided by Cinnamon. Having code flagged
by it doesn't automatically disqualify a pull request.

This check is not perfect will not replace a normal review.

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Found 12 potential issue(s):

⚠️ sync_spawn_command_line

mic-input/files/mic-input/applet.js:56

let [result, stdout, stderr] = GLib.spawn_command_line_sync('pactl get-default-source');

Synchronous process spawning blocks the main loop.
Use GLib.spawn_command_line_async() or Gio.Subprocess instead.

mic-input/files/mic-input/applet.js:68

let [result, stdout, stderr] = GLib.spawn_command_line_sync('pactl get-source-volume ' + source);

Synchronous process spawning blocks the main loop.
Use GLib.spawn_command_line_async() or Gio.Subprocess instead.

mic-input/files/mic-input/applet.js:84

let [result, stdout, stderr] = GLib.spawn_command_line_sync('pactl get-source-mute ' + source);

Synchronous process spawning blocks the main loop.
Use GLib.spawn_command_line_async() or Gio.Subprocess instead.

⚠️ lang_bind

mic-input/files/mic-input/applet.js:28

this._timeoutId = Mainloop.timeout_add_seconds(1, Lang.bind(this, this._updateVolume));

Lang.bind() is deprecated. Use arrow functions (() => {}) or Function.prototype.bind() instead.

mic-input/files/mic-input/applet.js:33

this.muteSwitch.connect('toggled', Lang.bind(this, this._onMuteToggled));

Lang.bind() is deprecated. Use arrow functions (() => {}) or Function.prototype.bind() instead.

mic-input/files/mic-input/applet.js:42

this.volumeSlider.connect('value-changed', Lang.bind(this, this._onVolumeChanged));

Lang.bind() is deprecated. Use arrow functions (() => {}) or Function.prototype.bind() instead.

ℹ️ shell_string_spawn

mic-input/files/mic-input/applet.js:49

Util.spawnCommandLine("cinnamon-settings sound");

Prefer argument vector spawn functions over shell command strings.
This is especially important when arguments include untrusted input (user data,
filenames, settings values, etc.) as shell strings are vulnerable to injection.
Static command strings are generally fine, but argv is always safer.
Use Util.spawn(["cmd", "arg1", "arg2"]) or Util.trySpawn() instead.

mic-input/files/mic-input/applet.js:56

let [result, stdout, stderr] = GLib.spawn_command_line_sync('pactl get-default-source');

Prefer argument vector spawn functions over shell command strings.
This is especially important when arguments include untrusted input (user data,
filenames, settings values, etc.) as shell strings are vulnerable to injection.
Static command strings are generally fine, but argv is always safer.
Use Util.spawn(["cmd", "arg1", "arg2"]) or Util.trySpawn() instead.

mic-input/files/mic-input/applet.js:68

let [result, stdout, stderr] = GLib.spawn_command_line_sync('pactl get-source-volume ' + source);

Prefer argument vector spawn functions over shell command strings.
This is especially important when arguments include untrusted input (user data,
filenames, settings values, etc.) as shell strings are vulnerable to injection.
Static command strings are generally fine, but argv is always safer.
Use Util.spawn(["cmd", "arg1", "arg2"]) or Util.trySpawn() instead.

mic-input/files/mic-input/applet.js:84

let [result, stdout, stderr] = GLib.spawn_command_line_sync('pactl get-source-mute ' + source);

Prefer argument vector spawn functions over shell command strings.
This is especially important when arguments include untrusted input (user data,
filenames, settings values, etc.) as shell strings are vulnerable to injection.
Static command strings are generally fine, but argv is always safer.
Use Util.spawn(["cmd", "arg1", "arg2"]) or Util.trySpawn() instead.

mic-input/files/mic-input/applet.js:128

Util.spawnCommandLine("pactl set-source-volume " + source + " " + volume + "%");

Prefer argument vector spawn functions over shell command strings.
This is especially important when arguments include untrusted input (user data,
filenames, settings values, etc.) as shell strings are vulnerable to injection.
Static command strings are generally fine, but argv is always safer.
Use Util.spawn(["cmd", "arg1", "arg2"]) or Util.trySpawn() instead.

mic-input/files/mic-input/applet.js:139

Util.spawnCommandLine("pactl set-source-mute " + source + " " + muteValue);

Prefer argument vector spawn functions over shell command strings.
This is especially important when arguments include untrusted input (user data,
filenames, settings values, etc.) as shell strings are vulnerable to injection.
Static command strings are generally fine, but argv is always safer.
Use Util.spawn(["cmd", "arg1", "arg2"]) or Util.trySpawn() instead.

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Automated pattern check.

[Skatterbrainz]

I'm not sure I submitted this PR correctly, my first time doing this. Hopefully someone will let me know if I need to make any corrections. Thank you!