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// stacktrace.h (c) 2008, Timo Bingmann from http://idlebox.net/
// published under the WTFPL v2.0
#ifndef _STACKTRACE_H_
#define _STACKTRACE_H_
#include <stdio.h>
#include <stdlib.h>
#ifndef _MSC_VER
#include <execinfo.h>
#include <cxxabi.h>
#endif
/** Print a demangled stack backtrace of the caller function to FILE* out. */
inline
std::string get_stacktrace(std::string& stack_str,
unsigned int max_frames = 256)
{
#ifdef _MSC_VER
(void) max_frames;
stack_str = "MSVC, stack trace not implemented.";
#else
// storage array for stack trace address data
void* addrlist[max_frames+1];
// retrieve current stack addresses
int addrlen = backtrace(addrlist, (int)(sizeof(addrlist) / sizeof(void*)));
if (addrlen == 0) {
stack_str = " <empty, possibly corrupt>\n";
return stack_str;
}
// 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
stack_str.append(symbollist[i]);
stack_str.append(" : ");
stack_str.append(funcname);
stack_str.append("+");
stack_str.append(begin_offset);
stack_str.append("\n");
}
else {
// demangling failed. Output function name as a C function with
// no arguments.
stack_str.append(symbollist[i]);
stack_str.append(" : ");
stack_str.append(begin_name);
stack_str.append("+");
stack_str.append(begin_offset);
stack_str.append("\n");
}
}
else
{
// couldn't parse the line? print the whole line.
stack_str.append(symbollist[i]);
stack_str.append("\n");
}
}
free(funcname);
free(symbollist);
#endif
return stack_str;
}
#endif // _STACKTRACE_H_