1 files changed, 26 insertions, 3 deletions
diff --git a/libcorkscrew/backtrace.c b/libcorkscrew/backtrace.c
index e57f428..3697d18 100644
--- a/libcorkscrew/backtrace.c
+++ b/libcorkscrew/backtrace.c
@@ -27,16 +27,41 @@
 
 #include <unistd.h>
 #include <signal.h>
+#include <stdlib.h>
+#include <string.h>
 #include <pthread.h>
 #include <unwind.h>
-#include <sys/exec_elf.h>
 #include <cutils/log.h>
 #include <cutils/atomic.h>
+#include <elf.h>
 
 #if HAVE_DLADDR
+#define __USE_GNU // For dladdr(3) in glibc.
 #include <dlfcn.h>
 #endif
 
+#if defined(__BIONIC__)
+
+// Bionic implements and exports gettid but only implements tgkill.
+extern int tgkill(int tgid, int tid, int sig);
+
+#else
+
+// glibc doesn't implement or export either gettid or tgkill.
+
+#include <unistd.h>
+#include <sys/syscall.h>
+
+static pid_t gettid() {
+  return syscall(__NR_gettid);
+}
+
+static int tgkill(int tgid, int tid, int sig) {
+  return syscall(__NR_tgkill, tgid, tid, sig);
+}
+
+#endif
+
 typedef struct {
     backtrace_frame_t* backtrace;
     size_t ignore_depth;
@@ -115,8 +140,6 @@ static void unwind_backtrace_thread_signal_handler(int n __attribute__((unused))
 }
 #endif
 
-extern int tgkill(int tgid, int tid, int sig);
-
 ssize_t unwind_backtrace_thread(pid_t tid, backtrace_frame_t* backtrace,
         size_t ignore_depth, size_t max_depth) {
     if (tid == gettid()) {