From a90c8e9e34ebe7142515d032f9f3a63b8bf6cf6f Mon Sep 17 00:00:00 2001
From: Victor Polevoy <fx@thefx.co>
Date: Sun, 5 Mar 2023 16:52:33 +0100
Subject: [PATCH] Support iOS

---
 Cargo.toml  |  4 ++--
 README.md   |  1 +
 src/lib.rs  |  2 ++
 src/unix.rs | 35 ++++++++++++++++++++++++++++++-----
 4 files changed, 35 insertions(+), 7 deletions(-)

diff --git a/Cargo.toml b/Cargo.toml
index 5a28184..cb3f470 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "thread-priority"
-version = "0.13.1"
+version = "0.14.0"
 authors = ["Victor Polevoy <fx@thefx.co>"]
 description = "Library for managing threads priority and schedule policies"
 repository = "https://github.com/vityafx/thread-priority"
@@ -20,7 +20,7 @@ cfg-if = "1"
 rustversion = "1"
 bitflags = "1"
 
-[target.'cfg(any(target_os = "linux", target_os = "android", target_os = "macos", target_os = "dragonfly", target_os = "freebsd", target_os = "openbsd", target_os = "netbsd"))'.dependencies]
+[target.'cfg(any(target_os = "linux", target_os = "android", target_os = "macos", target_os = "ios", target_os = "dragonfly", target_os = "freebsd", target_os = "openbsd", target_os = "netbsd"))'.dependencies]
 libc = ">=0.2.123"
 
 [target.'cfg(windows)'.dependencies]
diff --git a/README.md b/README.md
index 5ecafa5..6bfbb2c 100644
--- a/README.md
+++ b/README.md
@@ -17,6 +17,7 @@ Is `1.46`. If you need any help making it possible to compile with `1.36` please
 - OpenBSD
 - NetBSD
 - macOS
+- iOS
 - Windows
 
 ## Examples
diff --git a/src/lib.rs b/src/lib.rs
index 32181fc..9060af6 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -148,6 +148,7 @@
 #[cfg(any(
     target_os = "linux",
     target_os = "macos",
+    target_os = "ios",
     target_os = "dragonfly",
     target_os = "freebsd",
     target_os = "openbsd",
@@ -162,6 +163,7 @@ use std::time::Duration;
 #[cfg(any(
     target_os = "linux",
     target_os = "macos",
+    target_os = "ios",
     target_os = "dragonfly",
     target_os = "freebsd",
     target_os = "openbsd",
diff --git a/src/unix.rs b/src/unix.rs
index b653c49..15802b1 100644
--- a/src/unix.rs
+++ b/src/unix.rs
@@ -49,7 +49,7 @@ fn errno() -> libc::c_int {
                 *libc::__errno()
             } else if #[cfg(target_os = "linux")] {
                 *libc::__errno_location()
-            } else if #[cfg(any(target_os = "macos", target_os = "freebsd"))] {
+            } else if #[cfg(any(target_os = "macos", target_os = "ios", target_os = "freebsd"))] {
                 *libc::__error()
             } else {
                 compile_error!("Your OS is probably not supported.")
@@ -65,7 +65,7 @@ fn set_errno(number: libc::c_int) {
                 *libc::__errno() = number;
             } else if #[cfg(target_os = "linux")] {
                 *libc::__errno_location() = number;
-            } else if #[cfg(any(target_os = "macos", target_os = "freebsd"))] {
+            } else if #[cfg(any(target_os = "macos", target_os = "ios", target_os = "freebsd"))] {
                 *libc::__error() = number;
             } else {
                 compile_error!("Your OS is probably not supported.")
@@ -305,7 +305,16 @@ impl ThreadPriority {
             }
             ThreadSchedulePolicy::Normal(_) => {
                 // Niceness can be used, from -20 to 19, where `-20` is the maximum.
-                Ok(NICENESS_MAX as libc::c_int)
+                #[cfg(any(target_os = "linux", target_os = "android"))]
+                return Ok(NICENESS_MAX as libc::c_int);
+
+                // On other systems there is no notion of using niceness
+                // for just threads but for whole processes instead.
+                #[cfg(not(any(target_os = "linux", target_os = "android")))]
+                Err(Error::Priority(
+                    "This OS doesn't support specifying this thread priority with this policy.
+                    Consider changing the scheduling policy.",
+                ))
             }
             _ => {
                 let max_priority = unsafe { libc::sched_get_priority_max(policy.to_posix()) };
@@ -326,7 +335,19 @@ impl ThreadPriority {
             ThreadSchedulePolicy::Normal(NormalThreadSchedulePolicy::Idle) => Ok(0),
             ThreadSchedulePolicy::Normal(_) => {
                 // Niceness can be used, from -20 to 19, where `-20` is the maximum.
-                Ok(NICENESS_MIN as libc::c_int)
+                #[cfg(any(target_os = "linux", target_os = "android"))]
+                {
+                    Ok(NICENESS_MIN as libc::c_int)
+                }
+                // On other systems there is no notion of using niceness
+                // for just threads but for whole processes instead.
+                #[cfg(not(any(target_os = "linux", target_os = "android")))]
+                {
+                    Err(Error::Priority(
+                        "This OS doesn't support specifying this thread priority with this policy.
+                    Consider changing the scheduling policy.",
+                    ))
+                }
             }
             _ => {
                 let min_priority = unsafe { libc::sched_get_priority_min(policy.to_posix()) };
@@ -524,7 +545,11 @@ pub fn set_thread_priority_and_policy(
         }
         _ => {
             let fixed_priority = priority.to_posix(policy)?;
-            if let ThreadSchedulePolicy::Realtime(_) = policy {
+            // On macOS and iOS it is possible to set the priority
+            // this way.
+            if matches!(policy, ThreadSchedulePolicy::Realtime(_))
+                || cfg!(any(target_os = "macos", target_os = "ios"))
+            {
                 // If the policy is a realtime one, the priority is set via
                 // pthread_setschedparam.
                 let params = ScheduleParams {