From c17546faff2ecdc688cdcb25875a26492d43733e Mon Sep 17 00:00:00 2001
From: Harald Welte <laforge@osmocom.org>
Date: Mon, 28 Mar 2022 15:38:28 +0200
Subject: [PATCH] vty: Support platforms that don't support
 pthread_getname_np()

pthread_getname_np() is a non-portable extension of pthreads.  While
it exists in glibc, for example musl didn't have it until rather
recently (April 2021) and there still hasn't yet been a musl release
with this change, resulting even current OpenWRT not yet supporting
pthread_getname_np.

So let's check if pthread_getname_np is supported, and only use it
in that case.

Change-Id: Ibd01485af24e2fe574006f8d049bf37226dda966
---
 configure.ac            | 18 ++++++++++++++++++
 src/vty/cpu_sched_vty.c |  4 ++++
 2 files changed, 22 insertions(+)

diff --git a/configure.ac b/configure.ac
index 021092679..990d0e7e1 100644
--- a/configure.ac
+++ b/configure.ac
@@ -78,6 +78,24 @@ AC_SUBST(BACKTRACE_LIB)
 # check for pthread (PTHREAD_CFLAGS, PTHREAD_LIBS)
 AX_PTHREAD
 
+AC_MSG_CHECKING(for pthread_getname_np(pthread_t, char*, size_t))
+saved_CFLAGS="$CFLAGS"
+saved_LIBS="$LIBS"
+CFLAGS="$CFLAGS $PTHREAD_CFLAGS"
+LIBS="$LIBS $PTHREAD_LIBS"
+AC_LINK_IFELSE(
+	       [AC_LANG_PROGRAM(
+		[#define _GNU_SOURCE
+		 #include <pthread.h>],
+		[pthread_getname_np(pthread_self(),"example",0)])],
+	       [AC_MSG_RESULT(yes)
+	        AC_DEFINE(HAVE_PTHREAD_GETNAME_NP,1,
+		 [Have function pthread_setname_np(const char*)])],
+	       [AC_MSG_RESULT(no)])
+CFLAGS="$saved_CFLAGS"
+LIBS="$saved_LIBS"
+
+
 # check for old glibc < 2.17 to get clock_gettime
 AC_SEARCH_LIBS([clock_gettime], [rt posix4],
 	       [AC_DEFINE(HAVE_CLOCK_GETTIME, 1, [Define if clock_gettime is available])
diff --git a/src/vty/cpu_sched_vty.c b/src/vty/cpu_sched_vty.c
index 0b4b24921..dbb3cd59a 100644
--- a/src/vty/cpu_sched_vty.c
+++ b/src/vty/cpu_sched_vty.c
@@ -25,6 +25,8 @@
 
 #define _GNU_SOURCE
 
+#include "../../config.h"
+
 #include <string.h>
 #include <stdlib.h>
 #include <errno.h>
@@ -637,8 +639,10 @@ int osmo_cpu_sched_vty_apply_localthread(void)
 		return 0;
 	}
 
+#ifdef HAVE_PTHREAD_GETNAME_NP
 	if (pthread_getname_np(pthread_self(), name, sizeof(name)) == 0)
 		has_name = true;
+#endif
 
 	/* Get latest matching mask for the thread */
 	pthread_mutex_lock(&sched_vty_opts->cpu_affinity_li_mutex);