diff options
author | Nat Goodspeed <nat@lindenlab.com> | 2019-11-18 20:22:45 -0500 |
---|---|---|
committer | Nat Goodspeed <nat@lindenlab.com> | 2020-03-25 19:21:16 -0400 |
commit | 9ef702db1149b6961a4c9b158bf203007c0d3a92 (patch) | |
tree | 91334b328d3dd36e4ddf245db3bc96e4ee6ca053 | |
parent | b41a2eff4545b361afbee5d32f5d0f679702b203 (diff) |
DRTVWR-476: Enrich LLExceptions thrown by LLTHROW() with stack trace.
The LLTHROW() abstraction allows us to enrich the subject exception with a
boost::stacktrace -- without having to propagate the boost/stacktrace.hpp
header throughout the code base.
To my delight, our existing use of
boost::current_exception_diagnostic_information() already reports the newly
added boost::stacktrace information -- we don't have to query it specifically!
-rw-r--r-- | indra/llcommon/llexception.cpp | 27 | ||||
-rw-r--r-- | indra/llcommon/llexception.h | 26 |
2 files changed, 50 insertions, 3 deletions
diff --git a/indra/llcommon/llexception.cpp b/indra/llcommon/llexception.cpp index b32ec2c9c9..c0483e8927 100644 --- a/indra/llcommon/llexception.cpp +++ b/indra/llcommon/llexception.cpp @@ -18,10 +18,23 @@ #include <typeinfo> // external library headers #include <boost/exception/diagnostic_information.hpp> +#include <boost/exception/error_info.hpp> +// On Mac, got: +// #error "Boost.Stacktrace requires `_Unwind_Backtrace` function. Define +// `_GNU_SOURCE` macro or `BOOST_STACKTRACE_GNU_SOURCE_NOT_REQUIRED` if +// _Unwind_Backtrace is available without `_GNU_SOURCE`." +#define BOOST_STACKTRACE_GNU_SOURCE_NOT_REQUIRED +#include <boost/stacktrace.hpp> // other Linden headers #include "llerror.h" #include "llerrorcontrol.h" +// used to attach and extract stacktrace information to/from boost::exception, +// see https://www.boost.org/doc/libs/release/doc/html/stacktrace/getting_started.html#stacktrace.getting_started.exceptions_with_stacktrace +// apparently the struct passed as the first template param needs no definition? +typedef boost::error_info<struct errinfo_stacktrace_, boost::stacktrace::stacktrace> + errinfo_stacktrace; + namespace { // used by crash_on_unhandled_exception_() and log_unhandled_exception_() void log_unhandled_exception_(LLError::ELevel level, @@ -53,3 +66,17 @@ void log_unhandled_exception_(const char* file, int line, const char* pretty_fun // routinely, but we DO expect to return from this function. log_unhandled_exception_(LLError::LEVEL_WARN, file, line, pretty_function, context); } + +void annotate_exception_(boost::exception& exc) +{ + // https://www.boost.org/doc/libs/release/libs/exception/doc/tutorial_transporting_data.html + // "Adding of Arbitrary Data to Active Exception Objects" + // Given a boost::exception&, we can add boost::error_info items to it + // without knowing its leaf type. + // The stacktrace constructor that lets us skip a level -- and why would + // we always include annotate_exception_()? -- also requires a max depth. + // For the nullary constructor, the stacktrace class declaration itself + // passes static_cast<std::size_t>(-1), but that's kind of dubious. + // Anyway, which of us is really going to examine more than 100 frames? + exc << errinfo_stacktrace(boost::stacktrace::stacktrace(1, 100)); +} diff --git a/indra/llcommon/llexception.h b/indra/llcommon/llexception.h index dfcb7c192f..422dd8810a 100644 --- a/indra/llcommon/llexception.h +++ b/indra/llcommon/llexception.h @@ -67,9 +67,29 @@ struct LLContinueError: public LLException * enriches the exception's diagnostic_information() with the source file, * line and containing function of the LLTHROW() macro. */ -// Currently we implement that using BOOST_THROW_EXCEPTION(). Wrap it in -// LLTHROW() in case we ever want to revisit that implementation decision. -#define LLTHROW(x) BOOST_THROW_EXCEPTION(x) +#define LLTHROW(x) \ +do { \ + /* Capture the exception object 'x' by value. (Exceptions must */ \ + /* be copyable.) It might seem simpler to use */ \ + /* BOOST_THROW_EXCEPTION(annotate_exception_(x)) instead of */ \ + /* three separate statements, but: */ \ + /* - We want to throw 'x' with its original type, not just a */ \ + /* reference to boost::exception. */ \ + /* - To return x's original type, annotate_exception_() would */ \ + /* have to be a template function. */ \ + /* - We want annotate_exception_() to be opaque. */ \ + /* We also might consider embedding BOOST_THROW_EXCEPTION() in */ \ + /* our helper function, but we want the filename and line info */ \ + /* embedded by BOOST_THROW_EXCEPTION() to be the throw point */ \ + /* rather than always indicating the same line in */ \ + /* llexception.cpp. */ \ + auto exc{x}; \ + annotate_exception_(exc); \ + BOOST_THROW_EXCEPTION(exc); \ + /* Use the classic 'do { ... } while (0)' macro trick to wrap */ \ + /* our multiple statements. */ \ +} while (0) +void annotate_exception_(boost::exception& exc); /// Call this macro from a catch (...) clause #define CRASH_ON_UNHANDLED_EXCEPTION(CONTEXT) \ |