commit aa63d9f980f95718fc28ca7e222c1e8d7ca9e778
author Christopher Ferris <cferris@google.com> Tue Apr 29 09:35:30 2014 -0700
committer Christopher Ferris <cferris@google.com> Wed Apr 30 16:32:47 2014 -0700
tree 98901cf725457fc80c71c6a4bede3fda4e172cb0
parent f3661cc2f124bb7ca38285f156c624dda974b4c5

Use real time signal for threads instead of SIGURG.

This guarantees that any application is not also using this signal
for some other purpose.

Change-Id: I7c9bbb0ec8bb4e13322ecda951bcd43c6bf6ee1a

libbacktrace/BacktraceThread.cpp

diff --git a/libbacktrace/BacktraceThread.cpp b/libbacktrace/BacktraceThread.cpp
index 4cda19e..e0bab24 100644
--- a/libbacktrace/BacktraceThread.cpp
+++ b/libbacktrace/BacktraceThread.cpp
@@ -136,7 +136,7 @@
 bool BacktraceThread::TriggerUnwindOnThread(ThreadEntry* entry) {
   entry->state = STATE_WAITING;
 
-  if (tgkill(Pid(), Tid(), SIGURG) != 0) {
+  if (tgkill(Pid(), Tid(), THREAD_SIGNAL) != 0) {
     BACK_LOGW("tgkill failed %s", strerror(errno));
     return false;
   }
@@ -196,9 +196,9 @@
     act.sa_sigaction = SignalHandler;
     act.sa_flags = SA_RESTART | SA_SIGINFO | SA_ONSTACK;
     sigemptyset(&act.sa_mask);
-    if (sigaction(SIGURG, &act, &oldact) == 0) {
+    if (sigaction(THREAD_SIGNAL, &act, &oldact) == 0) {
       retval = TriggerUnwindOnThread(entry);
-      sigaction(SIGURG, &oldact, NULL);
+      sigaction(THREAD_SIGNAL, &oldact, NULL);
     } else {
       BACK_LOGW("sigaction failed %s", strerror(errno));
     }