{

// 32 vs. 64bit

#define ADDRESSDISPLAYLENGTH ((sizeof(long)==8)?12:8)

const int fd = fileno(output);

void *callstackArray[32]= {nullptr}; // the less resources the better...

const int currentdepth = backtrace(callstackArray, (int)getArrayLength(callstackArray));

const int offset=2; // some entries on top are within our own exception handling code or libc

if (maxdepth<0)

maxdepth=currentdepth-offset;

else

maxdepth = std::min(maxdepth, currentdepth);

if (lowMem) {

fputs("Callstack (symbols only):\n", output);

backtrace_symbols_fd(callstackArray+offset, maxdepth, fd);

} else {

char **symbolStringList = backtrace_symbols(callstackArray, currentdepth);

if (symbolStringList) {

fputs("Callstack:\n", output);

char demangle_buffer[2048]= {0};

for (int i = offset; i < maxdepth; ++i) {

const char * const symbolString = symbolStringList[i];

char * realnameString = nullptr;

const char * const firstBracketName = strchr(symbolString, '(');

const char * const firstBracketAddress = strchr(symbolString, '[');

const char * const secondBracketAddress = strchr(firstBracketAddress, ']');

const char * const beginAddress = firstBracketAddress+3;

const int addressLen = int(secondBracketAddress-beginAddress);

const int padLen = int(ADDRESSDISPLAYLENGTH-addressLen);

if (demangling && firstBracketName) {

const char * const plus = strchr(firstBracketName, '+');

if (plus && (plus>(firstBracketName+1))) {

char input_buffer[1024]= {0};

strncpy(input_buffer, firstBracketName+1, plus-firstBracketName-1);

size_t length = getArrayLength(demangle_buffer);

int status=0;

// We're violating the specification - passing stack address instead of malloc'ed heap.

// Benefit is that no further heap is required, while there is sufficient stack...

realnameString = abi::__cxa_demangle(input_buffer, demangle_buffer, &length, &status); // non-NULL on success

}

}

const int ordinal=i-offset;

fprintf(output, "#%-2d 0x",

ordinal);

if (padLen>0)

fprintf(output, "%0*d",

padLen, 0);

if (realnameString) {

fprintf(output, "%.*s in %s\n",

(int)(secondBracketAddress-firstBracketAddress-3), firstBracketAddress+3,

realnameString);

} else {

fprintf(output, "%.*s in %.*s\n",

(int)(secondBracketAddress-firstBracketAddress-3), firstBracketAddress+3,

(int)(firstBracketAddress-symbolString), symbolString);

}

}

free(symbolStringList);

} else {

fputs("Callstack could not be obtained\n", output);

}

}

#undef ADDRESSDISPLAYLENGTH