test: add sigabbrev_np() for systems where it's not available

sigabbrev_np() was first added to glibc 2.32 (Aug 2020) which is too recent
for some of the distributions we support.

test/pwtest-compat.c

@@ -0,0 +1,55 @@
+/* PipeWire
+ *
+ * Copyright © 2021 Red Hat, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ */
+
+#include "config.h"
+
+#if !HAVE_SIGABBREV_NP
+#include <stddef.h>
+#include <signal.h>
+
+/* glibc >= 2.32 */
+static inline const char *sigabbrev_np(int sig)
+{
+#define SIGABBREV(a_) case SIG##a_: return #a_
+	switch(sig) {
+	SIGABBREV(INT);
+	SIGABBREV(ABRT);
+	SIGABBREV(BUS);
+	SIGABBREV(SEGV);
+	SIGABBREV(ALRM);
+	SIGABBREV(CHLD);
+	SIGABBREV(HUP);
+	SIGABBREV(PIPE);
+	SIGABBREV(CONT);
+	SIGABBREV(STOP);
+	SIGABBREV(ILL);
+	SIGABBREV(KILL);
+	SIGABBREV(TERM);
+	}
+#undef SIGABBREV
+
+	return NULL;
+}
+
+#endif /* HAVE_SIGABBREV_NP */