Add a test for clock_gettime() supported clocks

This probes the system for available clocks to see if they can be
reliably used to get a monotonic-like timer (the test doesn't verify the
monotonic part, just usability).

2 files changed, 162 insertions, 2 deletions

diff --git a/tests/Makefile.am b/tests/Makefile.am
index 441af73..45f73fc 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -20,7 +20,7 @@
 
 TESTS = test_dict test_set test_tio test_expr test_getpeercred test_cfg \
         test_myldap.sh test_common test_nsscmds.sh test_pamcmds.sh \
-        test_manpages.sh
+        test_manpages.sh test_clock
 if HAVE_PYTHON
   TESTS += test_pycompile.sh test_pylint.sh
 endif
@@ -31,7 +31,7 @@ endif
 AM_TESTS_ENVIRONMENT = PYTHON='@PYTHON@'; export PYTHON;
 
 check_PROGRAMS = test_dict test_set test_tio test_expr test_getpeercred \
-                 test_cfg test_myldap test_common \
+                 test_cfg test_myldap test_common test_clock \
                  lookup_netgroup lookup_shadow
 
 EXTRA_DIST = nslcd-test.conf usernames.txt in_testenv.sh test_myldap.sh \
@@ -85,6 +85,8 @@ test_myldap_LDADD = ../nslcd/cfg.o $(common_nslcd_LDADD)
 test_common_SOURCES = test_common.c ../nslcd/common.h
 test_common_LDADD = ../nslcd/cfg.o $(common_nslcd_LDADD)
 
+test_clock_SOURCES = test_clock.c
+
 lookup_netgroup_SOURCES = lookup_netgroup.c
 
 lookup_shadow_SOURCES = lookup_shadow.c
diff --git a/tests/test_clock.c b/tests/test_clock.c
new file mode 100644
index 0000000..8d55f93
--- /dev/null
+++ b/tests/test_clock.c
@@ -0,0 +1,158 @@
+/*
+   test_clock.c - tests for finding usable system clocks
+   This file is part of the nss-pam-ldapd library.
+
+   Copyright (C) 2013 Arthur de Jong
+
+   This library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   This library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with this library; if not, write to the Free Software
+   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+   02110-1301 USA
+*/
+
+#include "config.h"
+
+#include <stdio.h>
+#include <assert.h>
+#include <time.h>
+#include <errno.h>
+#include <string.h>
+#include <stdlib.h>
+
+#include "compat/attrs.h"
+
+/* use clock_gettime() to see if the specified clock is supported */
+static int test_clock_gettime(clockid_t c, const char *cname)
+{
+  struct timespec t1 = {0, 0};
+  struct timespec t2 = {0, 0};
+  struct timespec t3 = {0, 50 * 1000 * 1000}; /* 50 msec */
+  struct timespec t4 = {0, 0};
+  long diff;
+  int result = 0;
+  /* see if we can get resolution (not important so ignore any failures) */
+  errno = 0;
+  if (clock_getres(c, &t1))
+    printf("     clock %s resolution not supported: %s\n", cname, strerror(errno));
+  if ((t1.tv_sec != 0) || (t1.tv_nsec != 0))
+    printf("     clock %s resolution: %ld.%09ld\n", cname, (long)t1.tv_sec, (long)t1.tv_nsec);
+  /* see if we can get the time */
+  errno = 0;
+  if (clock_gettime(c, &t2))
+  {
+    printf("FAIL clock %s get time not supported: %s\n",
+           cname, strerror(errno));
+    if ((t2.tv_sec != 0) || (t2.tv_nsec != 0))
+      printf("     clock %s time: %ld.%09ld\n", cname, (long)t2.tv_sec, (long)t2.tv_nsec);
+    return -1;
+  }
+  else
+    printf("OK   clock %s time: %ld.%09ld\n", cname, (long)t2.tv_sec, (long)t2.tv_nsec);
+  /* quick sleep (assume we're not interrupted) */
+  (void)nanosleep(&t3, NULL);
+  /* see if we can get the time again */
+  errno = 0;
+  if (clock_gettime(c, &t4))
+  {
+    printf("FAIL clock %s get time twice not supported: %s\n",
+           cname, strerror(errno));
+    if ((t4.tv_sec != 0) || (t4.tv_nsec != 0))
+      printf("     clock %s time: %ld.%09ld\n", cname, (long)t4.tv_sec, (long)t4.tv_nsec);
+    return -1;
+  }
+  else
+    printf("OK   clock %s time: %ld.%09ld\n", cname, (long)t4.tv_sec, (long)t4.tv_nsec);
+  /* calculate difference */
+  diff = ((long)t4.tv_sec - (long)t2.tv_sec - (long)t3.tv_sec) * (long)1000000000 +
+         ((long)t4.tv_nsec - (long)t2.tv_nsec - (long)t3.tv_nsec);
+  if ((diff < (-10 * 1000 * 1000)) || (diff > (20 * 1000 * 1000)))
+  {
+    result = -1;
+    printf("FAIL ");
+  }
+  else
+    printf("OK   ");
+  printf("clock %s time diff: %s%ld.%09ld %.1f%%\n", cname, (diff < 0) ? "-" : "",
+         (labs(diff) / 1000000000L), (labs(diff) % 1000000000L),
+         labs(100L * diff) / (float)((long)t3.tv_sec * 1000000000L + (long)t3.tv_nsec));
+  return result;
+}
+
+/* wrapper for test_clock_gettime() that passes the clock name */
+#define TEST_CLOCK_GETTIME(clock) test_clock_gettime(clock, #clock)
+
+int main(int UNUSED(argc), char UNUSED(*argv[]))
+{
+  int found_clocks = 0;
+#ifdef CLOCK_MONOTONIC_RAW
+  if (!TEST_CLOCK_GETTIME(CLOCK_MONOTONIC_RAW))
+    found_clocks++;
+#endif
+#ifdef CLOCK_MONOTONIC_FAST
+  if (!TEST_CLOCK_GETTIME(CLOCK_MONOTONIC_FAST))
+    found_clocks++;
+#endif
+#ifdef CLOCK_MONOTONIC_COARSE
+  if (!TEST_CLOCK_GETTIME(CLOCK_MONOTONIC_COARSE))
+    found_clocks++;
+#endif
+#ifdef CLOCK_MONOTONIC
+  if (!TEST_CLOCK_GETTIME(CLOCK_MONOTONIC))
+    found_clocks++;
+#endif
+#ifdef CLOCK_UPTIME_FAST
+  if (!TEST_CLOCK_GETTIME(CLOCK_UPTIME_FAST))
+    found_clocks++;
+#endif
+#ifdef CLOCK_UPTIME
+  if (!TEST_CLOCK_GETTIME(CLOCK_UPTIME))
+    found_clocks++;
+#endif
+#ifdef CLOCK_BOOTTIME
+  if (!TEST_CLOCK_GETTIME(CLOCK_BOOTTIME))
+    found_clocks++;
+#endif
+#ifdef CLOCK_MONOTONIC_PRECISE
+  if (!TEST_CLOCK_GETTIME(CLOCK_MONOTONIC_PRECISE))
+    found_clocks++;
+#endif
+#ifdef CLOCK_UPTIME_PRECISE
+  if (!TEST_CLOCK_GETTIME(CLOCK_UPTIME_PRECISE))
+    found_clocks++;
+#endif
+#ifdef CLOCK_HIGHRES
+#if CLOCK_HIGHRES == CLOCK_MONOTONIC
+  printf("     CLOCK_HIGHRES == CLOCK_MONOTONIC\n");
+#else
+  /* for Solaris, should be similar to CLOCK_MONOTONIC (it may be an alias) */
+  if (!TEST_CLOCK_GETTIME(CLOCK_HIGHRES))
+    found_clocks++;
+#endif
+#endif
+#ifdef CLOCK_REALTIME_FAST
+  if (!TEST_CLOCK_GETTIME(CLOCK_REALTIME_FAST))
+    found_clocks++;
+#endif
+#ifdef CLOCK_REALTIME_COARSE
+  if (!TEST_CLOCK_GETTIME(CLOCK_REALTIME_COARSE))
+    found_clocks++;
+#endif
+  if (!TEST_CLOCK_GETTIME(CLOCK_REALTIME))
+    found_clocks++;
+#ifdef CLOCK_REALTIME_PRECISE
+  if (!TEST_CLOCK_GETTIME(CLOCK_REALTIME_PRECISE))
+    found_clocks++;
+#endif
+  printf("%d usable clocks found\n", found_clocks);
+  return !(found_clocks > 0);
+}