Skip to content

[EH] Tidy up format_exception.cpp (NFC) #16995

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
aheejin merged 1 commit into from
May 20, 2022
Merged

[EH] Tidy up format_exception.cpp (NFC) #16995

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
43 changes: 25 additions & 18 deletions system/lib/libcxxabi/src/format_exception.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -1,39 +1,46 @@
#include "cxa_exception.h"
#include "cxxabi.h"
#include "private_typeinfo.h"
#include <stdio.h>
#include <typeinfo>

#ifdef __USING_EMSCRIPTEN_EXCEPTIONS__

extern "C" {
using namespace __cxxabiv1;

// Utility routines copied from cxa_exception.cpp
static inline __cxa_exception*
cxa_exception_from_thrown_object(void* thrown_object) {
return static_cast<__cxa_exception*>(thrown_object) - 1;
}

@sbc100 sbc100 May 20, 2022

Copy link
Copy Markdown
Collaborator

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

I have another change that also adds this function: #16627

But I don't mind merging them when I land that.


int __cxa_can_catch(const std::type_info* catchType,
const std::type_info* excpType,
void** thrown);
extern "C" {

char* emscripten_format_exception(void* exc_ptr) {
__cxxabiv1::__cxa_exception* exc_info =
(__cxxabiv1::__cxa_exception*)exc_ptr - 1;
std::type_info* exc_type = exc_info->exceptionType;
const char* exc_name = exc_type->name();
char* emscripten_format_exception(void* thrown_object) {
__cxa_exception* exception_header =
cxa_exception_from_thrown_object(thrown_object);
const __shim_type_info* thrown_type =
static_cast<const __shim_type_info*>(exception_header->exceptionType);
const char* type_name = thrown_type->name();

int status = 0;
char* demangled_buf = __cxxabiv1::__cxa_demangle(exc_name, 0, 0, &status);
char* demangled_buf = __cxa_demangle(type_name, 0, 0, &status);
if (status == 0 && demangled_buf) {
exc_name = demangled_buf;
type_name = demangled_buf;
}

int can_catch = __cxa_can_catch(&typeid(std::exception), exc_type, &exc_ptr);
const __shim_type_info* catch_type =
static_cast<const __shim_type_info*>(&typeid(std::exception));
int can_catch = catch_type->can_catch(thrown_type, thrown_object);
char* result = NULL;
if (can_catch) {
const char* exc_what = ((std::exception*)exc_ptr)->what();
asprintf(&result, "Cpp Exception %s: %s", exc_name, exc_what);
const char* what =
static_cast<const std::exception*>(thrown_object)->what();
asprintf(&result, "Cpp Exception %s: %s", type_name, what);
} else {
asprintf(&result,
"Cpp Exception: The exception is an object of type '%s' at "
"address %p which does not inherit from std::exception",
exc_name,
exc_ptr);
type_name,
thrown_object);
}

if (demangled_buf) {
Expand Down