linux_like: unify SIGEV_THREAD_ID support

This effectively adds the constant for musl too, as last platform of
this category.

It has been supported in musl since

  7c71792e ("add support for SIGEV_THREAD_ID timers")

and was released with v1.2.2 in January 2021.

Also double-checked that the `sigevent` struct is defined in the exact
same way.

Signed-off-by: Christoph Heiss <c.heiss@proxmox.com>

Author: christoph-heiss

libc-test/semver/linux-musl.txt

@@ -24,6 +24,7 @@ PIDFD_NONBLOCK
 PR_SET_VMA
 PR_SET_VMA_ANON_NAME
 SOL_XDP
+SIGEV_THREAD_ID
 XDP_SHARED_UMEM
 XDP_COPY
 XDP_ZEROCOPY

src/unix/linux_like/android/mod.rs

@@ -2204,8 +2204,6 @@ pub const NLA_TYPE_MASK: ::c_int = !(NLA_F_NESTED | NLA_F_NET_BYTEORDER);
 
 pub const NLA_ALIGNTO: ::c_int = 4;
 
-pub const SIGEV_THREAD_ID: ::c_int = 4;
-
 pub const CIBAUD: ::tcflag_t = 0o02003600000;
 pub const CBAUDEX: ::tcflag_t = 0o010000;
 

src/unix/linux_like/linux/gnu/mod.rs

@@ -819,8 +819,6 @@ pub const PF_NFC: ::c_int = AF_NFC;
 pub const PF_VSOCK: ::c_int = AF_VSOCK;
 pub const PF_XDP: ::c_int = AF_XDP;
 
-pub const SIGEV_THREAD_ID: ::c_int = 4;
-
 pub const BUFSIZ: ::c_uint = 8192;
 pub const TMP_MAX: ::c_uint = 238328;
 pub const FOPEN_MAX: ::c_uint = 16;

src/unix/linux_like/linux/uclibc/mod.rs

@@ -169,8 +169,6 @@ pub const MCL_CURRENT: ::c_int = 0x0001;
 pub const MCL_FUTURE: ::c_int = 0x0002;
 pub const MCL_ONFAULT: ::c_int = 0x0004;
 
-pub const SIGEV_THREAD_ID: ::c_int = 4;
-
 pub const AF_VSOCK: ::c_int = 40;
 
 // Most `*_SUPER_MAGIC` constants are defined at the `linux_like` level; the

src/unix/linux_like/mod.rs

@@ -1269,6 +1269,11 @@ pub const CLD_CONTINUED: ::c_int = 6;
 pub const SIGEV_SIGNAL: ::c_int = 0;
 pub const SIGEV_NONE: ::c_int = 1;
 pub const SIGEV_THREAD: ::c_int = 2;
+cfg_if! {
+    if #[cfg(not(target_os = "emscripten"))] {
+        pub const SIGEV_THREAD_ID: ::c_int = 4;
+    }
+}
 
 pub const P_ALL: idtype_t = 0;
 pub const P_PID: idtype_t = 1;