tests/uid.test: adopt for alpha

Make the test work on alpha that has getxuid syscall instead of getuid.

* tests/uid.awk (BEGIN): Update getuid regexp to match both getuid
and getxuid syscalls.
* tests/uid.c (main): Allow __NR_getxuid as an alternative
to __NR_getuid.
* tests/uid.test: If getuid syscall is not available, probe for
getxuid syscall.

tests/uid.awk

@@ -1,6 +1,6 @@
 BEGIN {
   r_uint = "(0|[1-9][0-9]*)"
-  regexp = "^getuid" suffix "\\(\\)[[:space:]]+= " r_uint "$"
+  regexp = "^getx?uid" suffix "\\(\\)[[:space:]]+= " r_uint "$"
   expected = "getuid"
   fail = 0
 }

tests/uid.c

@@ -9,7 +9,7 @@
 int
 main(void)
 {
-#if defined(__NR_getuid) \
+#if (defined __NR_getuid || defined __NR_getxuid) \
  && defined(__NR_setuid) \
  && defined(__NR_getresuid) \
  && defined(__NR_setreuid) \
@@ -20,6 +20,9 @@ main(void)
 	int size;
 	int *list = 0;
 
+#ifndef __NR_getuid
+# define __NR_getuid __NR_getxuid
+#endif
 	uid = syscall(__NR_getuid);
 	assert(syscall(__NR_setuid, uid) == 0);
 	{

tests/uid.test

@@ -9,7 +9,17 @@ w="${uid_t_size-}"
 
 run_prog ./uid$s$w
 
-syscalls="getuid$s,setuid$s,getresuid$s,setreuid$s,setresuid$s,fchown$s,getgroups$s"
+syscalls=
+for n in "getuid$s" "getxuid$s"; do
+	if $STRACE -e "$n" -h > /dev/null; then
+		syscalls="$n"
+		break
+	fi
+done
+test -n "$syscalls" ||
+        fail_ "neither getuid$s nor getxuid$s is supported on this architecture"
+
+syscalls="$syscalls,setuid$s,getresuid$s,setreuid$s,setresuid$s,fchown$s,getgroups$s"
 run_strace -e trace="$syscalls" $args
 
 AWK=gawk