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#include <assert.h>
#include <string.h>
#include <stdio.h>
#include "rd_route.h"

static char* my_strerror(int err)
{
  return "It's OK";
}

static char* my_super_strerror(int err)
{
  return "It's super OK";
}

int main (void)
{

    void *(*original)(int) = NULL;
    int err = 2;

    // hook strerror with my_strerror and backup implementation at original
    rd_route(strerror, my_strerror, (void **)&original);
    
    // See if the patch works
    assert(0 == strcmp("It's OK", strerror(err)));

    // See if an original implementation is still available
    assert(0 == strcmp("No such file or directory", original(err)));


    // hook my_strerror by name with my_super_strerror and backup patched implementation at original
    rd_route_byname("my_strerror", NULL, my_super_strerror, (void **)&original);

    // See if the patch by name works
    assert(0 == strcmp("It's super OK", my_strerror(err)));
    assert(0 == strcmp("It's super OK", strerror(err)));

    // See if an original patched implementation is still available
    assert(0 == strcmp("It's OK", original(err)));

    return 0;
}