From dbdafb6cc503ce5820713dfa79cc956438b7957a Mon Sep 17 00:00:00 2001
From: David CARLIER <devnexen@gmail.com>
Date: Wed, 19 Apr 2023 22:49:14 +0100
Subject: [PATCH] os: expand sched_getaffinity wrapper and update freebsd's
 cpuset api flags.

---
 lib/std/c/freebsd.zig | 13 +++++++++++++
 lib/std/os.zig        | 35 +++++++++++++++++++++++++++--------
 2 files changed, 40 insertions(+), 8 deletions(-)

diff --git a/lib/std/c/freebsd.zig b/lib/std/c/freebsd.zig
index 795b9a695e..534b6bc592 100644
--- a/lib/std/c/freebsd.zig
+++ b/lib/std/c/freebsd.zig
@@ -13,6 +13,19 @@ pub const cpulevel_t = c_int;
 pub const cpuwhich_t = c_int;
 pub const id_t = i64;
 
+pub const CPU_LEVEL_ROOT: cpulevel_t = 1;
+pub const CPU_LEVEL_CPUSET: cpulevel_t = 2;
+pub const CPU_LEVEL_WHICH: cpulevel_t = 3;
+pub const CPU_WHICH_TID: cpuwhich_t = 1;
+pub const CPU_WHICH_PID: cpuwhich_t = 2;
+pub const CPU_WHICH_CPUSET: cpuwhich_t = 3;
+pub const CPU_WHICH_IRQ: cpuwhich_t = 4;
+pub const CPU_WHICH_JAIL: cpuwhich_t = 5;
+pub const CPU_WHICH_DOMAIN: cpuwhich_t = 6;
+pub const CPU_WHICH_INTRHANDLER: cpuwhich_t = 7;
+pub const CPU_WHICH_ITHREAD: cpuwhich_t = 8;
+pub const CPU_WHICH_TIDPID: cpuwhich_t = 8;
+
 extern "c" fn __error() *c_int;
 pub const _errno = __error;
 
diff --git a/lib/std/os.zig b/lib/std/os.zig
index 6f4e027d14..13b0c62455 100644
--- a/lib/std/os.zig
+++ b/lib/std/os.zig
@@ -141,7 +141,12 @@ pub const addrinfo = system.addrinfo;
 pub const blkcnt_t = system.blkcnt_t;
 pub const blksize_t = system.blksize_t;
 pub const clock_t = system.clock_t;
-pub const cpu_set_t = system.cpu_set_t;
+pub const cpu_set_t = if (builtin.os.tag == .linux)
+    system.cpu_set_t
+else if (builtin.os.tag == .freebsd)
+    freebsd.cpuset_t
+else
+    u32;
 pub const dev_t = system.dev_t;
 pub const dl_phdr_info = system.dl_phdr_info;
 pub const empty_sigset = system.empty_sigset;
@@ -5518,13 +5523,27 @@ pub const SchedGetAffinityError = error{PermissionDenied} || UnexpectedError;
 
 pub fn sched_getaffinity(pid: pid_t) SchedGetAffinityError!cpu_set_t {
     var set: cpu_set_t = undefined;
-    switch (errno(system.sched_getaffinity(pid, @sizeOf(cpu_set_t), &set))) {
-        .SUCCESS => return set,
-        .FAULT => unreachable,
-        .INVAL => unreachable,
-        .SRCH => unreachable,
-        .PERM => return error.PermissionDenied,
-        else => |err| return unexpectedErrno(err),
+    if (builtin.os.tag == .linux) {
+        switch (errno(system.sched_getaffinity(pid, @sizeOf(cpu_set_t), &set))) {
+            .SUCCESS => return set,
+            .FAULT => unreachable,
+            .INVAL => unreachable,
+            .SRCH => unreachable,
+            .PERM => return error.PermissionDenied,
+            else => |err| return unexpectedErrno(err),
+        }
+    } else if (builtin.os.tag == .freebsd) {
+        switch (errno(freebsd.cpuset_getaffinity(freebsd.CPU_LEVEL_WHICH, freebsd.CPU_WHICH_PID, pid, @sizeOf(cpu_set_t), &set))) {
+            .SUCCESS => return set,
+            .FAULT => unreachable,
+            .INVAL => unreachable,
+            .SRCH => unreachable,
+            .EDEADLK => unreachable,
+            .PERM => return error.PermissionDenied,
+            else => |err| return unexpectedErrno(err),
+        }
+    } else {
+        @compileError("unsupported platform");
     }
 }