tests: core_routes: Handle limit of rlimit's soft limit

By default, macOS's soft limit of rlimit is up to 256.
SO, just eating up 256 of output instances could cause too many open
errors.

Signed-off-by: Hiroshi Hatake <hiroshi@chronosphere.io>

Author: cosmo0920

tests/runtime/core_routes.c

@@ -2,6 +2,12 @@
 
 #include <fluent-bit.h>
 #include <fluent-bit/flb_time.h>
+#ifdef FLB_SYSTEM_MACOS
+#include <stdio.h>
+#include <string.h>
+#include <errno.h>
+#include <sys/resource.h>
+#endif
 #include "flb_tests_runtime.h"
 
 pthread_mutex_t result_mutex = PTHREAD_MUTEX_INITIALIZER;
@@ -44,7 +50,11 @@ void flb_test_basic_functionality_test(void)
     int                   result;
     size_t                index;
     flb_ctx_t            *ctx;
-
+    size_t                olimit = 257;
+#ifdef FLB_SYSTEM_MACOS
+    struct rlimit rlim;
+    int           rlimit_rc;
+#endif
     cb_context = 0;
 
     /* Prepare output callback with expected result */
@@ -56,9 +66,20 @@ void flb_test_basic_functionality_test(void)
     input_instance = flb_input(ctx, (char *) "lib", NULL);
     TEST_CHECK(input_instance >= 0);
 
+#ifdef FLB_SYSTEM_MACOS
+    rlimit_rc = getrlimit(RLIMIT_NOFILE, &rlim);
+    TEST_CHECK(rlimit_rc == 0);
+    if (rlimit_rc == 0 && rlim.rlim_cur < 257) {
+        olimit = (size_t) (rlim.rlim_cur / 2.5);
+        if (olimit == 0) {
+            olimit = 1;
+        }
+    }
+#endif
+
     flb_input_set(ctx, input_instance, "tag", "test", NULL);
 
-    for (index = 0 ; index < 257 ; index++) {
+    for (index = 0 ; index < olimit ; index++) {
         output_instances[index] = flb_output(ctx, (char *) "lib", &cb_data);
         TEST_CHECK(output_instances[index] >= 0);
 
@@ -82,14 +103,14 @@ void flb_test_basic_functionality_test(void)
     delivery_counter = get_output_num();
 
     for (index = 0 ;
-         index < 100 && delivery_counter < 257 ;
+         index < 100 && delivery_counter < olimit ;
          index++) {
         flb_time_msleep(100);
 
         delivery_counter = get_output_num();
     }
 
-    TEST_CHECK(delivery_counter == 257);
+    TEST_CHECK(delivery_counter == olimit);
 
     flb_stop(ctx);
     flb_destroy(ctx);