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#include <cpptrace/cpptrace.hpp>
#include <algorithm>
#include <cctype>
#include <iostream>
#include <string>
#include <sys/wait.h>
#include <cstring>
#include <signal.h>
#include <csignal>
#include <unistd.h>
void trace() {
*(volatile char*)0 = 2;
}
void bar() {
trace();
}
void foo() {
bar();
}
struct pipe_t {
union {
struct {
int read_end;
int write_end;
};
int data[2];
};
};
static_assert(sizeof(pipe_t) == 2 * sizeof(int), "Unexpected struct packing");
void handler(int signo, siginfo_t* info, void* context) {
const char* message = "SIGSEGV occurred:\n";
write(STDERR_FILENO, message, strlen(message));
cpptrace::frame_ptr buffer[100];
std::size_t count = cpptrace::safe_generate_raw_trace(buffer, 100);
pipe_t input_pipe;
pipe(input_pipe.data);
const pid_t pid = fork();
if(pid == -1) {
const char* fork_failure_message = "fork() failed\n";
write(STDERR_FILENO, fork_failure_message, strlen(fork_failure_message));
_exit(1);
}
if(pid == 0) { // child
dup2(input_pipe.read_end, STDIN_FILENO);
close(input_pipe.read_end);
close(input_pipe.write_end);
execl(
"signal_tracer",
"signal_tracer",
nullptr
);
const char* exec_failure_message = "exec(signal_tracer) failed: Make sure the signal_tracer executable is in "
"the current working directory and the binary's permissions are correct.\n";
write(STDERR_FILENO, exec_failure_message, strlen(exec_failure_message));
_exit(1);
}
for(std::size_t i = 0; i < count; i++) {
cpptrace::safe_object_frame frame;
cpptrace::get_safe_object_frame(buffer[i], &frame);
write(input_pipe.write_end, &frame, sizeof(frame));
}
close(input_pipe.read_end);
close(input_pipe.write_end);
waitpid(pid, nullptr, 0);
_exit(1);
}
void warmup_cpptrace() {
cpptrace::frame_ptr buffer[10];
std::size_t count = cpptrace::safe_generate_raw_trace(buffer, 10);
cpptrace::safe_object_frame frame;
cpptrace::get_safe_object_frame(buffer[0], &frame);
}
int main() {
cpptrace::absorb_trace_exceptions(false);
cpptrace::use_default_stderr_logger();
cpptrace::register_terminate_handler();
warmup_cpptrace();
struct sigaction action = { 0 };
action.sa_flags = 0;
action.sa_sigaction = &handler;
if (sigaction(SIGSEGV, &action, NULL) == -1) {
perror("sigaction");
exit(EXIT_FAILURE);
}
foo();
}
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