feat: add support for multiple bars (#8)

SketchyBar allows for multiple bar by symlinking to `sketchybar` and
running a second process (eg. `bottombar`). In order for the helper to
find the `mach` port for the targeted bar we need to provide the bar
processes name.

FelixKratz/SketchyBar#353 (comment)
FelixKratz/SketchyBarHelper#2

Cargo.toml

@@ -15,4 +15,4 @@ license = "MIT"
 libc = "0.2.151"
 
 [build-dependencies]
-cc = "1.0.84"
+cc = "1.0.83"

src/lib.rs

@@ -29,7 +29,7 @@ impl Error for SketchybarError {}
 
 #[link(name = "sketchybar", kind = "static")]
 extern "C" {
-    fn sketchybar(message: *mut i8) -> *mut i8;
+    fn sketchybar(message: *mut i8, bar_name: *mut i8) -> *mut i8;
 }
 
 /// Sends a message to `SketchyBar` and returns the response.
@@ -38,6 +38,10 @@ extern "C" {
 ///
 /// * `message` - A string slice containing the message to be sent to
 /// `SketchyBar`.
+/// * `bar_name` - An optional string slice containing the name of the process
+/// of the target bar. This defaults to `sketchybar` however, if you're using a
+/// secondary bar (eg. a `bottombar`) you can override the default there to pass
+/// a message to this other bar.
 ///
 /// # Returns
 ///
@@ -68,12 +72,18 @@ extern "C" {
 ///     println!("Response from SketchyBar: {}", response);
 /// }
 /// ```
-pub fn message(message: &str) -> Result<String, SketchybarError> {
+pub fn message(
+    message: &str,
+    bar_name: Option<&str>,
+) -> Result<String, SketchybarError> {
     let command = CString::new(message)
         .map_err(|_| SketchybarError::MessageConversionError)?;
 
+    let bar_name = CString::new(bar_name.unwrap_or("sketchybar"))
+        .map_err(|_| SketchybarError::MessageConversionError)?;
+
     let result = unsafe {
-        CStr::from_ptr(sketchybar(command.into_raw()))
+        CStr::from_ptr(sketchybar(command.into_raw(), bar_name.into_raw()))
             .to_string_lossy()
             .into_owned()
     };

src/sketchybar.h

@@ -50,7 +50,7 @@ char* env_get_value_for_key(env env, char* key) {
   return (char*)"";
 }
 
-mach_port_t mach_get_bs_port() {
+mach_port_t mach_get_bs_port(char* bar_name) {
   mach_port_name_t task = mach_task_self();
 
   mach_port_t bs_port;
@@ -60,9 +60,12 @@ mach_port_t mach_get_bs_port() {
     return 0;
   }
 
+  char service_name[256]; // Assuming the service name will not exceed 255 chars
+  snprintf(service_name, sizeof(service_name), "git.felix.%s", bar_name);
+
   mach_port_t port;
   if (bootstrap_look_up(bs_port,
-                        "git.felix.sketchybar",
+                        service_name,
                         &port                  ) != KERN_SUCCESS) {
     return 0;
   }
@@ -190,7 +193,7 @@ bool mach_server_begin(struct mach_server* mach_server, mach_handler handler, ch
 }
 #pragma clang diagnostic pop
 
-char* sketchybar(char* message) {
+char* sketchybar(char* message, char* bar_name) {
   uint32_t message_length = strlen(message) + 1;
   char formatted_message[message_length + 1];
 
@@ -213,7 +216,7 @@ char* sketchybar(char* message) {
   }
 
   formatted_message[caret] = '\0';
-  if (!g_mach_port) g_mach_port = mach_get_bs_port();
+  if (!g_mach_port) g_mach_port = mach_get_bs_port(bar_name);
   char* response = mach_send_message(g_mach_port,
                                      formatted_message,
                                      caret + 1          );