/* gcc stack.c -o stack -pthread */

#define _GNU_SOURCE // for pthread_getattr_np
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <pthread.h>

void print_stack(void)
{
    size_t used, avail;
    pthread_attr_t attr;
    void *stack_addr;
    size_t stack_size;

    size_t esp_val;
    if(sizeof(void*) == 8) {
        asm("movq %%rsp, %0" : "=m"(esp_val) :); // x86_64
    }
    else {
        asm("movl %%esp, %0" : "=m"(esp_val) :); // x86
    }

    memset(&attr, 0, sizeof(pthread_attr_t));
    pthread_getattr_np(pthread_self(), &attr);
    pthread_attr_getstack(&attr, &stack_addr, &stack_size);
    pthread_attr_destroy(&attr);

    printf("statck top   = %p \n", stack_addr);
    printf("espVal       = %p \n", (void*)esp_val);
    printf("stack bottom = %p \n", stack_addr + stack_size);

    avail = esp_val - (size_t)stack_addr;
    used = stack_size - avail;

    printf("print_stack1: used = %ld, avail = %ld, total = %ld \n",
                                                    used, avail, stack_size);

    for(size_t i=0; i<=used; i+=16) {
        printf("%p : ", (void*)esp_val + i);
        for(size_t j=0; j<16; j++) {
            printf("%02X ", ((unsigned char*)esp_val)[i + j]);
        }
        printf("\n");
    }
    printf("\n");
}

int main(int argc, char *argv[])
{
    (void)argc;
    (void)argv;

    print_stack();
    return 0;
}