RetroShare/libretroshare/src/util/stacktrace.h

/*
 * stacktrace.h
 *
 * Copyright (C) 2016 Gioacchino Mazzurco <gio@eigenlab.org>
 * Copyright (C) 2008 Timo Bingmann http://idlebox.net/
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License Version 2 as published by the Free Software Foundation.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
 * USA.
 *
 */

#ifndef _STACKTRACE_H_
#define _STACKTRACE_H_

#include <stdio.h>

#if !defined(WINDOWS_SYS) && !defined(__ANDROID__)

#include <stdlib.h>
#include <execinfo.h>
#include <cxxabi.h>

/** Print a demangled stack backtrace of the caller function to FILE* out. */
static inline void print_stacktrace(FILE *out = stderr, unsigned int max_frames = 63)
{
	fprintf(out, "stack trace:\n");

	// storage array for stack trace address data
	void* addrlist[max_frames+1];

	// retrieve current stack addresses
	int addrlen = backtrace(addrlist, sizeof(addrlist) / sizeof(void*));

	if (addrlen == 0)
	{
		fprintf(out, "  <empty, possibly corrupt>\n");
		return;
	}

	// resolve addresses into strings containing "filename(function+address)",
	// this array must be free()-ed
	char** symbollist = backtrace_symbols(addrlist, addrlen);

	// allocate string which will be filled with the demangled function name
	size_t funcnamesize = 256;
	char* funcname = (char*)malloc(funcnamesize);

	// iterate over the returned symbol lines. skip the first, it is the
	// address of this function.
	for (int i = 1; i < addrlen; i++)
	{
		char *begin_name = 0, *begin_offset = 0, *end_offset = 0;

		// find parentheses and +address offset surrounding the mangled name:
		// ./module(function+0x15c) [0x8048a6d]
		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';

			// mangled name is now in [begin_name, begin_offset) and caller
			// offset in [begin_offset, end_offset). now apply
			// __cxa_demangle():

			int status;
			char* ret = abi::__cxa_demangle(begin_name, funcname, &funcnamesize, &status);
			if (status == 0)
			{
				funcname = ret; // use possibly realloc()-ed string
				fprintf(out, "  %s : %s+%s\n", symbollist[i], funcname, begin_offset);
			}
			else
			{
				// demangling failed. Output function name as a C function with
				// no arguments.
				fprintf(out, "  %s : %s()+%s\n", symbollist[i], begin_name, begin_offset);
			}
		}
		else
		{
			// couldn't parse the line? print the whole line.
			fprintf(out, "  %s\n", symbollist[i]);
		}
	}

	free(funcname);
	free(symbollist);
}

#else // !defined(WINDOWS_SYS) && !defined(__ANDROID__)
static inline void print_stacktrace(FILE *out = stderr, unsigned int max_frames = 63)
{
	(void) max_frames;

	fprintf(out, "TODO: 2016/01/01 print_stacktrace not implemented yet for WINDOWS_SYS and ANDROID\n");
}
#endif // !defined(WINDOWS_SYS) && !defined(__ANDROID__)

#endif // _STACKTRACE_H_