Bind to capture's macOS C frameworks with bindgen

Nathan Sobo created 3 years ago

Change summary

Cargo.lock                     |  1 +
crates/capture/Cargo.toml      |  1 +
crates/capture/build.rs        | 23 ++++++++++++++++++++++-
crates/capture/src/bindings.h  |  2 ++
crates/capture/src/bindings.rs |  5 +++++
crates/capture/src/main.rs     | 34 ++++++++++++++--------------------
6 files changed, 45 insertions(+), 21 deletions(-)

Detailed changes

Cargo.lock

@@ -754,6 +754,7 @@ dependencies = [
 name = "capture"
 version = "0.1.0"
 dependencies = [
+ "bindgen",
  "block",
  "cc",
  "cocoa",

crates/capture/Cargo.toml

@@ -21,4 +21,5 @@ objc = "0.2"
 simplelog = "0.9"
 
 [build-dependencies]
+bindgen = "0.59.2"
 cc = "1.0"

crates/capture/build.rs

@@ -1,9 +1,30 @@
+use std::{env, path::PathBuf};
+
 fn main() {
-    println!("cargo:rustc-link-lib=framework=ScreenCaptureKit");
     println!("cargo:rustc-link-lib=framework=CoreMedia");
+    println!("cargo:rustc-link-lib=framework=ScreenCaptureKit");
+    println!("cargo:rustc-link-lib=framework=System");
     println!("cargo:rustc-env=MACOSX_DEPLOYMENT_TARGET=12.3");
     println!("cargo:rustc-link-arg=-ObjC");
 
+    let bindings = bindgen::Builder::default()
+        .header("src/bindings.h")
+        .clang_arg("-isysroot/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX12.3.sdk")
+        .allowlist_function("CMTimeMake")
+        .allowlist_type("CMSampleBufferRef")
+        .allowlist_var("_dispatch_main_q")
+        .allowlist_function("dispatch_async_f")
+        .allowlist_function("dispatch_queue_create")
+        .parse_callbacks(Box::new(bindgen::CargoCallbacks))
+        .layout_tests(false)
+        .generate()
+        .expect("unable to generate bindings");
+
+    let out_path = PathBuf::from(env::var("OUT_DIR").unwrap());
+    bindings
+        .write_to_file(out_path.join("bindings.rs"))
+        .expect("couldn't write dispatch bindings");
+
     cc::Build::new()
         .file("src/dummy.m")
         .flag("-mmacosx-version-min=12.3")

crates/capture/src/bindings.h

@@ -0,0 +1,2 @@
+#import <CoreMedia/CMSampleBuffer.h>
+#import <dispatch/dispatch.h>

crates/capture/src/bindings.rs

@@ -0,0 +1,5 @@
+include!(concat!(env!("OUT_DIR"), "/bindings.rs"));
+
+pub fn dispatch_get_main_queue() -> dispatch_queue_t {
+    unsafe { &_dispatch_main_q as *const _ as dispatch_queue_t }
+}

crates/capture/src/main.rs

@@ -1,16 +1,19 @@
-use std::{ffi::CStr, slice, str, ptr};
+mod bindings;
+
+use std::{slice, str};
 
 use block::ConcreteBlock;
 use cocoa::{
     base::{id, nil},
     foundation::{NSArray, NSString, NSUInteger, NSInteger},
 };
-use core_graphics::display::CGDirectDisplayID;
-use gpui::{actions, elements::*, keymap::Binding, Menu, MenuItem, mac::dispatcher::{dispatch_get_main_queue, dispatch_queue_create}};
+use gpui::{actions, elements::*, keymap::Binding, Menu, MenuItem};
 use log::LevelFilter;
 use objc::{class, msg_send, sel, sel_impl, declare::ClassDecl, runtime::{Protocol, Object, Sel}};
 use simplelog::SimpleLogger;
 
+use crate::bindings::dispatch_get_main_queue;
+
 #[allow(non_upper_case_globals)]
 const NSUTF8StringEncoding: NSUInteger = 4;
 
@@ -57,6 +60,10 @@ fn main() {
                     let output: id = msg_send![capture_output_class, alloc];
                     let output: id = msg_send![output, init];
                     
+                    let conforms: bool = msg_send![output, conformsToProtocol: Protocol::get("SCStreamOutput").unwrap()];
+                    dbg!(conforms);
+                    assert!(conforms, "expect CaptureOutput instance to conform to SCStreamOutput protocol");
+                    
                     let excluded_windows: id = msg_send![class!(NSArray), array];
                     let filter: id = msg_send![class!(SCContentFilter), alloc];
                     let filter: id = msg_send![filter, initWithDisplay: display excludingWindows: excluded_windows];
@@ -65,14 +72,15 @@ fn main() {
                     // Configure the display content width and height.
                     let _: () = msg_send![config, setWidth: 800];
                     let _: () = msg_send![config, setHeight: 600];
-                    let _: () = msg_send![config, setMinimumFrameInterval: CMTimeMake(1, 60)];
+                    let _: () = msg_send![config, setMinimumFrameInterval: bindings::CMTimeMake(1, 60)];
                     let _: () = msg_send![config, setQueueDepth: 5];
                     
                     let stream: id = msg_send![class!(SCStream), alloc];
                     let stream: id = msg_send![stream, initWithFilter: filter configuration: config delegate: nil];
                     let error: id = nil;
-                    let queue = dispatch_queue_create(ptr::null(), ptr::null_mut());
-                    let _: () = msg_send![stream, addStreamOutput: output type: 0 sampleHandlerQueue: queue error: &error];
+                    // let queue = dispatch_queue_create(ptr::null(), ptr::null_mut());
+                    
+                    let _: () = msg_send![stream, addStreamOutput: output type: 0 sampleHandlerQueue: dispatch_get_main_queue() error: &error];
                     
                     let start_capture_completion = ConcreteBlock::new(move |error: id| {
                         if !error.is_null() {
@@ -126,20 +134,6 @@ extern "C" fn sample_output(this: &Object, _: Sel, stream: id, buffer: id, kind:
     println!("sample_output");
 }
 
-
-extern "C" {
-    fn CMTimeMake(value: u64, timescale: i32) -> CMTime;
-}
-
-#[repr(C)]
-struct CMTime {
-	value: i64,
-	timescale: i32,
-	flags: u32,
-	epoch: i64,
-}
-
-
 fn quit(_: &Quit, cx: &mut gpui::MutableAppContext) {
     cx.platform().quit();
 }