1 files changed, 74 insertions, 0 deletions
diff --git a/src/common/BackTrace.cc b/src/common/BackTrace.cc
new file mode 100644
index 000000000..42a8da2ae
--- /dev/null
+++ b/src/common/BackTrace.cc
@@ -0,0 +1,74 @@
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab
+
+#include <ostream>
+#include <cxxabi.h>
+#include <string.h>
+
+#include "BackTrace.h"
+#include "common/version.h"
+#include "common/Formatter.h"
+
+namespace ceph {
+
+void BackTrace::print(std::ostream& out) const
+{
+  out << " " << pretty_version_to_str() << std::endl;
+  for (size_t i = skip; i < size; i++) {
+    out << " " << (i-skip+1) << ": " << demangle(strings[i]) << std::endl;
+  }
+}
+
+void BackTrace::dump(Formatter *f) const
+{
+  f->open_array_section("backtrace");
+  for (size_t i = skip; i < size; i++) {
+    //      out << " " << (i-skip+1) << ": " << strings[i] << std::endl;
+    f->dump_string("frame", demangle(strings[i]));
+  }
+  f->close_section();
+}
+
+std::string BackTrace::demangle(const char* name)
+{
+  // find the parentheses and address offset surrounding the mangled name
+#ifdef __FreeBSD__
+  static constexpr char OPEN = '<';
+#else
+  static constexpr char OPEN = '(';
+#endif
+  const char* begin = nullptr;
+  const char* end = nullptr;
+  for (const char *j = name; *j; ++j) {
+    if (*j == OPEN) {
+      begin = j + 1;
+    } else if (*j == '+') {
+      end = j;
+    }
+  }
+  if (begin && end && begin < end) {
+    std::string mangled(begin, end);
+    int status;
+    // only demangle a C++ mangled name
+    if (mangled.compare(0, 2, "_Z") == 0) {
+      // let __cxa_demangle do the malloc
+      char* demangled = abi::__cxa_demangle(mangled.c_str(), nullptr, nullptr, &status);
+      if (!status) {
+        std::string full_name{OPEN};
+        full_name += demangled;
+        full_name += end;
+        // buf could be reallocated, so free(demangled) instead
+        free(demangled);
+        return full_name;
+      }
+      // demangle failed, just pretend it's a C function with no args
+    }
+    // C function
+    return mangled + "()";
+  } else {
+    // didn't find the mangled name, just print the whole line
+    return name;
+  }
+}
+
+}