macOS pre-10.13 support (#264)

* macOS < 10.13: skip log tests for want of fmemopen

There is a dependency on fmemopen in the tests for the logging
functions, which macOS introduced only in version 10.13.  There should
be no other obstacle to building/running/testing on older versions of
macOS.  This commit does the pragmatic thing: remove the dependency and
turns the tests into no-ops in this one case.

Signed-off-by: Erik Boasson <eb@ilities.com>

* Fix macOS clock_gettime_nsec_np availability test

Signed-off-by: Erik Boasson <eb@ilities.com>

src/ddsrt/tests/log.c

@@ -16,6 +16,7 @@
 
 #ifdef __APPLE__
 #include <pthread.h>
+#include <AvailabilityMacros.h>
 #endif /* __APPLE__ */
 
 #include "CUnit/Test.h"
@@ -27,7 +28,19 @@
 #include "dds/ddsrt/threads.h"
 #include "dds/ddsrt/time.h"
 
-static FILE *fh = NULL;
+/* On macOS, fmemopen was introduced in version 10.13.  The hassle of providing
+   an alternative implementation of it just for running a few sanity checks on an
+   old version of macOS isn't worth the bother.
+
+   The CUnit.cmake boiler-plate generator doesn't recognize #ifdef'ing tests away
+   because it runs on the source rather than on the output of the C preprocessor
+   (a reasonable decision in itself).  Therefore, just skip the body of each test. */
+
+#if __APPLE__ && MAC_OS_X_VERSION_MIN_REQUIRED < MAC_OS_X_VERSION_10_13
+#define HAVE_FMEMOPEN 0
+#else
+#define HAVE_FMEMOPEN 1
+#endif
 
 #ifdef _WIN32
 #include <fcntl.h>
@@ -104,6 +117,9 @@ FILE *fmemopen(void *buf, size_t size, const char *mode)
 }
 #endif /* _WIN32 */
 
+#if HAVE_FMEMOPEN
+static FILE *fh = NULL;
+
 static void count(void *ptr, const dds_log_data_t *data)
 {
   (void)data;
@@ -114,6 +130,7 @@ static void copy(void *ptr, const dds_log_data_t *data)
 {
   *(char **)ptr = ddsrt_strdup(data->message);
 }
+#endif
 
 static void reset(void)
 {
@@ -125,14 +142,18 @@ static void reset(void)
 
 static void setup(void)
 {
+#if HAVE_FMEMOPEN
   fh = fmemopen(NULL, 1024, "wb+");
   CU_ASSERT_PTR_NOT_NULL_FATAL(fh);
+#endif
 }
 
 static void teardown(void)
 {
   reset();
+#if HAVE_FMEMOPEN
   (void)fclose(fh);
+#endif
 }
 
 /* By default only DDS_LC_FATAL and DDS_LC_ERROR are set. This means setting a
@@ -140,6 +161,7 @@ static void teardown(void)
    enabled. The message should end up in the log file. */
 CU_Test(dds_log, only_log_file, .init=setup, .fini=teardown)
 {
+#if HAVE_FMEMOPEN
   char buf[1024], *ptr;
   int cnt = 0;
   size_t nbytes;
@@ -157,6 +179,7 @@ CU_Test(dds_log, only_log_file, .init=setup, .fini=teardown)
   /* No trace categories are enabled by default, verify trace callback was
      not invoked. */
   CU_ASSERT_EQUAL(cnt, 0);
+#endif
 }
 
 /* Messages must be printed to the trace file if at least one trace category
@@ -164,6 +187,7 @@ CU_Test(dds_log, only_log_file, .init=setup, .fini=teardown)
    same as the log file. */
 CU_Test(dds_log, same_file, .init=setup, .fini=teardown)
 {
+#if HAVE_FMEMOPEN
   char buf[1024], *ptr;
   size_t nbytes;
 
@@ -182,6 +206,7 @@ CU_Test(dds_log, same_file, .init=setup, .fini=teardown)
      occur again. */
   ptr = strstr(ptr + 1, "foobar\n");
   CU_ASSERT_PTR_NULL(ptr);
+#endif
 }
 
 /* The sinks are considered to be the same only if the callback and userdata
@@ -189,6 +214,7 @@ CU_Test(dds_log, same_file, .init=setup, .fini=teardown)
    be called twice for log messages. */
 CU_Test(dds_log, same_sink_function, .fini=reset)
 {
+#if HAVE_FMEMOPEN
   int log_cnt = 0, trace_cnt = 0;
 
   dds_set_log_mask(DDS_LC_ALL);
@@ -197,10 +223,12 @@ CU_Test(dds_log, same_sink_function, .fini=reset)
   DDS_ERROR("foo%s\n", "bar");
   CU_ASSERT_EQUAL(log_cnt, 1);
   CU_ASSERT_EQUAL(trace_cnt, 1);
+#endif
 }
 
 CU_Test(dds_log, exact_same_sink, .fini=reset)
 {
+#if HAVE_FMEMOPEN
   int cnt = 0;
 
   dds_set_log_mask(DDS_LC_ALL);
@@ -208,6 +236,7 @@ CU_Test(dds_log, exact_same_sink, .fini=reset)
   dds_set_trace_sink(&count, &cnt);
   DDS_ERROR("foo%s\n", "bar");
   CU_ASSERT_EQUAL(cnt, 1);
+#endif
 }
 
 /* The log file must be restored if the sink is unregistered, verify the log
@@ -215,6 +244,7 @@ CU_Test(dds_log, exact_same_sink, .fini=reset)
    restored again when the sink is unregistered. */
 CU_Test(dds_log, no_sink, .init=setup, .fini=teardown)
 {
+#if HAVE_FMEMOPEN
   int ret;
   char buf[1024], *ptr = NULL;
   size_t cnt[2] = {0, 0};
@@ -267,6 +297,7 @@ CU_Test(dds_log, no_sink, .init=setup, .fini=teardown)
   buf[cnt[1]] = '\0';
   ptr = strstr(buf, "foobaz\n");
   CU_ASSERT_PTR_NOT_NULL_FATAL(ptr);
+#endif
 }
 
 /* A newline terminates the message. Until that a newline is encountered, the
@@ -274,6 +305,7 @@ CU_Test(dds_log, no_sink, .init=setup, .fini=teardown)
    NULL byte if it is flushed to a sink. */
 CU_Test(dds_log, newline_terminates, .fini=reset)
 {
+#if HAVE_FMEMOPEN
   char *msg = NULL;
 
   dds_set_log_sink(&copy, &msg);
@@ -285,11 +317,13 @@ CU_Test(dds_log, newline_terminates, .fini=reset)
   CU_ASSERT_PTR_NOT_NULL_FATAL(msg);
   CU_ASSERT(strcmp(msg, "foobarbaz\n") == 0);
   ddsrt_free(msg);
+#endif
 }
 
 /* Nothing must be written unless a category is enabled. */
 CU_Test(dds_log, disabled_categories_discarded, .fini=reset)
 {
+#if HAVE_FMEMOPEN
   char *msg = NULL;
   dds_set_log_sink(&copy, &msg);
   DDS_INFO("foobar\n");
@@ -299,9 +333,10 @@ CU_Test(dds_log, disabled_categories_discarded, .fini=reset)
   CU_ASSERT_PTR_NOT_NULL_FATAL(msg);
   CU_ASSERT(strcmp(msg, "foobar\n") == 0);
   ddsrt_free(msg);
+#endif
 }
 
-
+#if HAVE_FMEMOPEN
 static ddsrt_cond_t cond;
 static ddsrt_mutex_t mutex;
 
@@ -337,12 +372,14 @@ static uint32_t run(void *ptr)
 
   return 0;
 }
+#endif
 
 /* Log and trace sinks can be changed at runtime. However, the operation must
    be synchronous! Verify the dds_set_log_sink blocks while other threads
    reside in the log or trace sinks. */
 CU_Test(dds_log, synchronous_sink_changes, .fini=reset)
 {
+#if HAVE_FMEMOPEN
   struct arg arg;
   ddsrt_thread_t tid;
   ddsrt_threadattr_t tattr;
@@ -364,4 +401,5 @@ CU_Test(dds_log, synchronous_sink_changes, .fini=reset)
 
   CU_ASSERT(arg.before < arg.after);
   CU_ASSERT(arg.after < dds_time());
+#endif
 }