[lttng-dev] [lttng-ust][PATCH V3] Add config time check for new gettid API

[Khem Raj]

glibc 2.30 introduced this function see [1]
so it's best to detect it
and provide fallback only if it's not present

[1] https://sourceware.org/bugzilla/show_bug.cgi?id=6399

Signed-off-by: Khem Raj <raj.khem at gmail.com>
---
v2: Fix typos in commit message
v3: Fix more typos in commit message

 configure.ac            | 1 +
 include/lttng/ust-tid.h | 7 +++++--
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/configure.ac b/configure.ac
index 7fa059a..b1099c1 100644
--- a/configure.ac
+++ b/configure.ac
@@ -137,6 +137,7 @@ AC_CHECK_FUNCS([ \
 	clock_gettime \
 	ftruncate \
 	getpagesize \
+	gettid \
 	gettimeofday \
 	localeconv \
 	memchr \
diff --git a/include/lttng/ust-tid.h b/include/lttng/ust-tid.h
index e669d7e..7995c78 100644
--- a/include/lttng/ust-tid.h
+++ b/include/lttng/ust-tid.h
@@ -26,7 +26,10 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  * SOFTWARE.
  */
-
+#include <config.h>
+#if HAVE_GETTID
+#include <unistd.h>
+#else
 #ifdef __linux__
 #include <syscall.h>
 #endif
@@ -49,5 +52,5 @@ static inline pid_t gettid(void)
 	return getpid();
 }
 #endif
-
+#endif /* HAVE_GETTID */
 #endif /* _LTTNG_UST_TID_H */
-- 
2.22.0