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glibc/elf/reldep3.c
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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 ("reldepmod4.so", RTLD_LAZY); | |
if (h2 == NULL) | |
{ | |
printf ("cannot open reldepmod4.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); | |
} | |
/* 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); | |
} | |
/* 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); | |
} | |
if (dlclose (h2) != 0) | |
{ | |
printf ("closing h2 failed: %s\n", dlerror ()); | |
exit (1); | |
} | |
return 0; | |
} |