From f40a7c1c8eeb8466a3db01964893c19141f90f58 Mon Sep 17 00:00:00 2001
From: Nathaniel <me@nathanielbennett.com>
Date: Sat, 17 Aug 2024 13:22:09 -0400
Subject: [PATCH] Linux: add `getitimer()`/`setitimer()`

---
 libc-test/build.rs               |  3 +++
 libc-test/semver/linux.txt       |  4 ++++
 src/unix/linux_like/linux/mod.rs | 37 ++++++++++++++++++++++++++++++++
 3 files changed, 44 insertions(+)

diff --git a/libc-test/build.rs b/libc-test/build.rs
index 26b1c550de22..f01830059676 100644
--- a/libc-test/build.rs
+++ b/libc-test/build.rs
@@ -3648,6 +3648,9 @@ fn test_linux(target: &str) {
             // in the `linux_elf.rs` file.
             "Elf64_Phdr" | "Elf32_Phdr" => true,
 
+            // musl doesn't define these; instead, it uses a raw int for getitimer/setitimer
+            "__itimer_which" | "__itimer_which_t" if musl => true,
+
             // On Linux, the type of `ut_tv` field of `struct utmpx`
             // can be an anonymous struct, so an extra struct,
             // which is absent in glibc, has to be defined.
diff --git a/libc-test/semver/linux.txt b/libc-test/semver/linux.txt
index c93940b82e48..2a61cdd2bd95 100644
--- a/libc-test/semver/linux.txt
+++ b/libc-test/semver/linux.txt
@@ -3475,6 +3475,8 @@ __c_anonymous_sockaddr_can_j1939
 __c_anonymous_sockaddr_can_tp
 __errno_location
 __exit_status
+__itimer_which
+__itimer_which_t
 __s16
 __s32
 __u16
@@ -3591,6 +3593,7 @@ getgrnam_r
 getgrouplist
 gethostid
 getifaddrs
+getitimer
 getline
 getmntent
 getnameinfo
@@ -3892,6 +3895,7 @@ setfsuid
 setgrent
 setgroups
 sethostname
+setitimer
 setmntent
 setns
 setpriority
diff --git a/src/unix/linux_like/linux/mod.rs b/src/unix/linux_like/linux/mod.rs
index 2ce09ed168df..10c75699ae0e 100644
--- a/src/unix/linux_like/linux/mod.rs
+++ b/src/unix/linux_like/linux/mod.rs
@@ -73,6 +73,21 @@ missing! {
     pub enum fpos64_t {} // FIXME: fill this out with a struct
 }
 
+cfg_if! {
+    if #[cfg(not(target_env = "musl"))] {
+        pub type __itimer_which_t = ::__itimer_which;
+
+        e! {
+            #[repr(i32)]
+            pub enum __itimer_which {
+                ITIMER_REAL = 0,
+                ITIMER_VIRTUAL = 1,
+                ITIMER_PROF = 2,
+            }
+        }
+    }
+}
+
 e! {
     pub enum tpacket_versions {
         TPACKET_V1,
@@ -6129,6 +6144,28 @@ extern "C" {
     pub fn ioctl(fd: ::c_int, request: ::Ioctl, ...) -> ::c_int;
 }
 
+cfg_if! {
+    if #[cfg(target_env = "musl")] {
+        extern "C" {
+            pub fn getitimer(which: ::c_int, value: *mut ::itimerval) -> ::c_int;
+            pub fn setitimer(
+                which: ::c_int,
+                new: *const ::itimerval,
+                old: *mut ::itimerval,
+            ) -> ::c_int;
+        }
+    } else {
+        extern "C" {
+            pub fn getitimer(which: ::__itimer_which_t, value: *mut ::itimerval) -> ::c_int;
+            pub fn setitimer(
+                which: ::__itimer_which_t,
+                new: *const ::itimerval,
+                old: *mut ::itimerval,
+            ) -> ::c_int;
+        }
+    }
+}
+
 // LFS64 extensions
 //
 // * musl has 64-bit versions only so aliases the LFS64 symbols to the standard ones