From b9307a99676354a77e0d93838777207f2626c74a Mon Sep 17 00:00:00 2001
From: Imberflur <2002109+Imberflur@users.noreply.github.com>
Date: Fri, 5 Feb 2021 02:58:55 -0500
Subject: [PATCH] Change linking of CGDisplayCreateUUIDFromDisplayID on macos
(#1626)
* Link CGDisplayCreateUUIDFromDisplayID through ColorSync instead of CoreGraphics
* Conditionally link through ColorSync only if WINIT_LINK_COLORSYNC is set
to true
* Document new macos env var in README
---
README.md | 10 ++++++++++
build.rs | 10 ++++++++++
src/platform_impl/macos/ffi.rs | 13 ++++++++++++-
3 files changed, 32 insertions(+), 1 deletion(-)
create mode 100644 build.rs
diff --git a/README.md b/README.md
index e387ec0d..8ba6518d 100644
--- a/README.md
+++ b/README.md
@@ -110,3 +110,13 @@ fn main() {
```
And run the application with `cargo apk run --example request_redraw_threaded`
+
+#### MacOS
+
+To ensure compatibility with older MacOS systems, winit links to
+CGDisplayCreateUUIDFromDisplayID through the CoreGraphics framework.
+However, under certain setups this function is only available to be linked
+through the newer ColorSync framework. So, winit provides the
+`WINIT_LINK_COLORSYNC` environment variable which can be set to `1` or `true`
+while compiling to enable linking via ColorSync.
+
diff --git a/build.rs b/build.rs
new file mode 100644
index 00000000..a092e636
--- /dev/null
+++ b/build.rs
@@ -0,0 +1,10 @@
+fn main() {
+ // If building for macos and WINIT_LINK_COLORSYNC is set to true
+ // use CGDisplayCreateUUIDFromDisplayID from ColorSync instead of CoreGraphics
+ if std::env::var("CARGO_CFG_TARGET_OS").map_or(false, |os| os == "macos")
+ && std::env::var("WINIT_LINK_COLORSYNC")
+ .map_or(false, |v| v == "1" || v.eq_ignore_ascii_case("true"))
+ {
+ println!("cargo:rustc-cfg=use_colorsync_cgdisplaycreateuuidfromdisplayid");
+ }
+}
diff --git a/src/platform_impl/macos/ffi.rs b/src/platform_impl/macos/ffi.rs
index aec0fc97..1bcdafba 100644
--- a/src/platform_impl/macos/ffi.rs
+++ b/src/platform_impl/macos/ffi.rs
@@ -161,6 +161,18 @@ pub const IO8BitOverlayPixels: &str = "O8";
pub type CGWindowLevel = i32;
pub type CGDisplayModeRef = *mut libc::c_void;
+#[cfg_attr(
+ not(use_colorsync_cgdisplaycreateuuidfromdisplayid),
+ link(name = "CoreGraphics", kind = "framework")
+)]
+#[cfg_attr(
+ use_colorsync_cgdisplaycreateuuidfromdisplayid,
+ link(name = "ColorSync", kind = "framework")
+)]
+extern "C" {
+ pub fn CGDisplayCreateUUIDFromDisplayID(display: CGDirectDisplayID) -> CFUUIDRef;
+}
+
#[link(name = "CoreGraphics", kind = "framework")]
extern "C" {
pub fn CGRestorePermanentDisplayConfiguration();
@@ -189,7 +201,6 @@ extern "C" {
synchronous: Boolean,
) -> CGError;
pub fn CGReleaseDisplayFadeReservation(token: CGDisplayFadeReservationToken) -> CGError;
- pub fn CGDisplayCreateUUIDFromDisplayID(display: CGDirectDisplayID) -> CFUUIDRef;
pub fn CGShieldingWindowLevel() -> CGWindowLevel;
pub fn CGDisplaySetDisplayMode(
display: CGDirectDisplayID,