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#include <dlfcn.h>
#include <stdio.h>
#include <assert.h>
#ifdef USE_HOST_LIBC
#define LIBBAR "libnative-bar.so"
#define LIBBAZ "libnative-baz.so"
#else
#define LIBBAR "libbar.so"
#define LIBBAZ "libbaz.so"
#endif
int main() {
// In this test, we have bar -> foo and baz -> foo (where -> means 'depends on').
// All three objects contain a definition of a symbol g. Bar calls into foo to retrieve
// what foo thinks g is, but since bar appears earlier in the scope than foo, bar's copy
// of g wins.
//
// Next, we load baz, which is identical to bar. When baz calls into foo to retrieve g,
// foo still sees bar's definition of g, so bar's copy of g wins.
//
// Swapping the load order of bar and baz should therefore change the value of g which
// foo sees. This behaviour is why dlmopen exists. If we ever implement that, we should
// write a similar test and assert that the calls return different results.
void *libbar = dlopen(LIBBAR, RTLD_LAZY | RTLD_LOCAL);
int (*call_bar)(void) = dlsym(libbar, "call_bar");
printf("call_bar: %d\n", call_bar());
assert(call_bar() == 1);
void *libbaz = dlopen(LIBBAZ, RTLD_LAZY | RTLD_LOCAL);
int (*call_baz)(void) = dlsym(libbaz, "call_baz");
printf("call_baz: %d\n", call_baz());
assert(call_baz() == 1);
dlclose(libbar);
dlclose(libbaz);
}
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