#include <control/signal_handling.h>
#include <cxxabi.h>
#include <execinfo.h>
#include <iostream>
#include <signal.h>
#include <unistd.h>

/*
 * crit_err_hdlr - stack trace for debugging
 * @sig_num - number of signal
 */
static void crit_err_hdlr(int sig_num __attribute__((unused)))
{
	void* addrlist[10];
	int addrlen = backtrace(addrlist, sizeof(addrlist) / sizeof(void*));
	
	if (!addrlen) {
		std::cerr << "Possible corruption\n";
		exit(EXIT_FAILURE);
	}
	
	char** symbollist = backtrace_symbols(addrlist, addrlen);
	
	size_t funcnamesize = 256;
	char* funcname = (char*) malloc(funcnamesize * sizeof(char));

	for (int i = 1; i < addrlen; i++) {
		char *begin_name = NULL;
		char *begin_offset = NULL;
		char *end_offset = NULL;

		for (char *p = symbollist[i]; *p; ++p) {
			if (*p == '(') {
				begin_name = p;
			} else if (*p == '+') {
				begin_offset = p;
			}else if (*p == ')' && begin_offset) {
				end_offset = p;
				break;
			}
		}

		if (begin_name && begin_offset && end_offset && begin_name < begin_offset) {
			*begin_name++ = '\0';
			*begin_offset++ = '\0';
			*end_offset = '\0';

			int status;
			char* ret = abi::__cxa_demangle(begin_name, funcname, &funcnamesize, &status);
			
			if (status == 0) {
				funcname = ret;
				fprintf(stderr, "  %s : %s+%s\n", symbollist[i], funcname, begin_offset);
			} else {
				fprintf(stderr, "  %s : %s()+%s\n", symbollist[i], begin_name, begin_offset);
			}
		} else {
			fprintf(stderr, "  %s\n", symbollist[i]);
		}
	}

	free(funcname);
	free(symbollist);
	
	exit(EXIT_FAILURE);
}

/*
 * init_signals - initializes the signals for signal handling
 */
void init_signals()
{
	signal(SIGSEGV, crit_err_hdlr);
}