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#include <dlfcn.h>
#include <mcheck.h>
#include <stdio.h>
#include <stdlib.h>
int
main (void)
{
void *h1;
void *h2;
int (*fp) (void);
int *vp;
mtrace ();
/* Open the two objects. */
h1 = dlopen ("reldepmod1.so", RTLD_LAZY | RTLD_GLOBAL);
if (h1 == NULL)
{
printf ("cannot open reldepmod1.so: %s\n", dlerror ());
exit (1);
}
h2 = dlopen ("reldepmod2.so", RTLD_LAZY);
if (h2 == NULL)
{
printf ("cannot open reldepmod2.so: %s\n", dlerror ());
exit (1);
}
/* Get the address of the variable in reldepmod1.so. */
vp = dlsym (h1, "some_var");
if (vp == NULL)
{
printf ("cannot get address of \"some_var\": %s\n", dlerror ());
exit (1);
}
*vp = 42;
/* Get the function `call_me' in the second object. This has a
dependency which is resolved by a definition in reldepmod1.so. */
fp = dlsym (h2, "call_me");
if (fp == NULL)
{
printf ("cannot get address of \"call_me\": %s\n", dlerror ());
exit (1);
}
/* Call the function. */
if (fp () != 0)
{
puts ("function \"call_me\" returned wrong result");
exit (1);
}
/* Now close the first object. If must still be around since we have
an implicit dependency. */
if (dlclose (h1) != 0)
{
printf ("closing h1 failed: %s\n", dlerror ());
exit (1);
}
/* Try calling the function again. This will fail if the first object
got unloaded. */
if (fp () != 0)
{
puts ("second call of function \"call_me\" returned wrong result");
exit (1);
}
/* Now close the second file as well. */
if (dlclose (h2) != 0)
{
printf ("closing h2 failed: %s\n", dlerror ());
exit (1);
}
/* Finally, open the first object again. */
h1 = dlopen ("reldepmod1.so", RTLD_LAZY | RTLD_GLOBAL);
if (h1 == NULL)
{
printf ("cannot open reldepmod1.so the second time: %s\n", dlerror ());
exit (1);
}
/* And get the variable address again. */
vp = dlsym (h1, "some_var");
if (vp == NULL)
{
printf ("cannot get address of \"some_var\" the second time: %s\n",
dlerror ());
exit (1);
}
/* The variable now must have its originial value. */
if (*vp != 0)
{
puts ("variable \"some_var\" not reset");
exit (1);
}
/* Close the first object again, we are done. */
if (dlclose (h1) != 0)
{
printf ("closing h1 failed: %s\n", dlerror ());
exit (1);
}
return 0;
}
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