#include <stdio.h>
#include <libunwind.h>
#include <unistd.h>

void customFunction1(int n);
void customFunction2(int n);
void customFunction3(int n);

// Call this function to get a backtrace.
void backtrace() {
  unw_cursor_t cursor;
  unw_context_t context;

  // Initialize cursor to current frame for local unwinding.
  unw_getcontext(&context);
  unw_init_local(&cursor, &context);

  // Unwind frames one by one, going up the frame stack.
  while (unw_step(&cursor) > 0) {
    unw_word_t offset, pc;
    unw_get_reg(&cursor, UNW_REG_IP, &pc);
    if (pc == 0) {
      break;
    }
    printf("0x%lx:", pc);

    char sym[256];
    if (unw_get_proc_name(&cursor, sym, sizeof(sym), &offset) == 0) {
      printf(" (%s+0x%lx)\n", sym, offset);
    } else {
      printf(" -- error: unable to obtain symbol name for this frame\n");
    }
  }
}

void customFunction1(int n) {
    if(n <= 0) {
        printf("End of recursion\n");
        // output backtrace
        printf("pid: %d\n", getpid());
        backtrace();
        while (1) {
            sleep(1);
        } // never return, keep stack
        return;
    } else {
        printf("Calling customFunction2\n");
        customFunction2(n-1);
    }
}

void customFunction2(int n) {
    printf("Calling customFunction3\n");
    customFunction3(n);
}

void customFunction3(int n) {
    printf("Calling customFunction1\n");
    customFunction1(n);
}

int main() {
    customFunction1(10);

    return 0;
}