BSD more friendly build.

Using native feature for proper TID report.

Author: devnexen

src/libmongoc/CMakeLists.txt

@@ -340,7 +340,10 @@ if (ENABLE_SHM_COUNTERS STREQUAL "ON")
          "Shared memory performance counters not supported on Mac or Windows")
    endif ()
    set (MONGOC_ENABLE_SHM_COUNTERS 1)
-   set (SHM_LIBRARIES rt)
+   find_library(RT_LIBRARY rt)
+   if (RT_LIBRARY)
+   	set (SHM_LIBRARIES rt)
+   endif ()
 endif ()
 
 if (NOT ENABLE_ICU MATCHES "AUTO|ON|OFF")

src/libmongoc/src/mongoc/mongoc-log.c

@@ -19,6 +19,8 @@
 #include <sys/syscall.h>
 #elif defined(_WIN32)
 #include <process.h>
+#elif defined(__FreeBSD__)
+#include <sys/thr.h>
 #else
 #include <unistd.h>
 #endif
@@ -171,6 +173,12 @@ mongoc_log_default_handler (mongoc_log_level_t log_level,
    pid = syscall (SYS_gettid);
 #elif defined(_WIN32)
    pid = (int) _getpid ();
+#elif defined(__FreeBSD__)
+   long tid;
+   thr_self (&tid);
+   pid = (int) tid;
+#elif defined(__OpenBSD__)
+   pid = (int) getthrid ();
 #else
    pid = (int) getpid ();
 #endif