1 files changed, 100 insertions, 0 deletions
diff --git a/btrace.c b/btrace.c
new file mode 100644
index 0000000..e9ade89
--- /dev/null
+++ b/btrace.c
@@ -0,0 +1,100 @@
+#include <execinfo.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+
+#define STACKTRACES 10
+
+
+static char *exec_path = NULL;
+
+
+void bt_set_arg0(const char *arg0) {
+	if (!exec_path && arg0) {
+		exec_path = strdup(arg0);
+	}
+}
+
+static void addr_to_array(char **strings, size_t siz, char **result) {
+	char *start, *end;
+
+	for (size_t i = 0; i < siz; ++i) {
+		start = strchr(strings[i], '+');
+		if (start) {
+			end = strchr(start, ')');
+			start++;
+			if (end)
+				result[i] = strndup(start, end-start);
+			else
+				result[i] = strdup("");
+		}
+	}
+}
+
+void bt_print_trace (void) {
+	void *array[STACKTRACES];
+	size_t bt_size;
+	char **strings;
+	size_t i;
+	char **addrs;
+
+	bt_size = backtrace(array, STACKTRACES);
+	strings = backtrace_symbols(array, bt_size);
+
+	printf("\n\n[1] Obtained %zd stack frames.\n", bt_size);
+	for (i = 0; i < bt_size; ++i)
+		printf("%s\n", strings[i]);
+
+	/* addr2line -p -e ./btrace -f -i [addresses] */
+	if (exec_path) {
+		addrs = (char**) calloc(bt_size, sizeof(*addrs));
+
+		addr_to_array(strings, bt_size, addrs);
+		printf("\n\n[2] Run for more info: addr2line -p -e %s -f -i", exec_path);
+		for (i = 0; i < bt_size; ++i) {
+			printf(" %s", addrs[i]);
+		}
+		printf("%s\n", "");
+
+		for (i = 0; i < bt_size; ++i)
+			if (addrs[i])
+				free(addrs[i]);
+		free(addrs);
+	}
+
+	free(strings);
+}
+
+void bt_sighandler(int signum) {
+	bt_print_trace();
+	switch (signum) {
+		case SIGTERM:
+		case SIGABRT:
+		case SIGSEGV:
+			exit(1);
+	}
+}
+
+
+
+
+/* A dummy function to make the backtrace more interesting. */
+void dummy_function(void) {
+	bt_print_trace();
+}
+
+#include <assert.h>
+int main(int argc, char **argv) {
+	bt_set_arg0(argv[0]);
+	dummy_function();
+	signal(SIGTERM, bt_sighandler);
+	signal(SIGABRT, bt_sighandler);
+	signal(SIGSEGV, bt_sighandler);
+
+	//assert(0);
+	*(int*)(NULL) = 0;
+	return 0;
+}