breakpoint: new module.

[ccan] / ccan / breakpoint / breakpoint.c

diff --git a/ccan/breakpoint/breakpoint.c b/ccan/breakpoint/breakpoint.c
new file mode 100644 (file)
index 0000000..279e29a
--- /dev/null
+++ b/ccan/breakpoint/breakpoint.c
@@ -0,0 +1,32 @@
+/* CC0 (Public domain) - see LICENSE file for details
+ *
+ * Idea for implementation thanks to stackoverflow.com:
+ *     http://stackoverflow.com/questions/3596781/detect-if-gdb-is-running
+ */
+#include <ccan/breakpoint/breakpoint.h>
+
+bool breakpoint_initialized;
+bool breakpoint_under_debug;
+
+/* This doesn't get called if we're under GDB. */
+static void trap(int signum)
+{
+       breakpoint_initialized = true;
+}
+
+void breakpoint_init(void)
+{
+       struct sigaction old, new;
+
+       new.sa_handler = trap;
+       new.sa_flags = 0;
+       sigemptyset(&new.sa_mask);
+       sigaction(SIGTRAP, &new, &old);
+       kill(getpid(), SIGTRAP);
+       sigaction(SIGTRAP, &old, NULL);
+
+       if (!breakpoint_initialized) {
+               breakpoint_initialized = true;
+               breakpoint_under_debug = true;
+       }
+}