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/*
* test-static-tls: Verify that libgtk3-nocsd.so doesn't use up an
* overflow DTV entry in the loaded program
*
* Logic is simple: try to dlopen() as many different libraries as
* possible that contain static TLS entries (62 were built by the
* Makefile), so that it can be determined what the cutoff is for
* the case with and without LD_PRELOAD. (The cutoff is limited by
* the number of overflow static DTV entries the dynamic linker
* users by default.)
*
* This program will output the number of libraries it could load.
*
* Threading is necessary, otherwise the DTV will not be used.
*/
#include <dlfcn.h>
#include <stdio.h>
#include <pthread.h>
#include <errno.h>
#include <string.h>
#include <unistd.h>
static const char alphabet[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";
static const char *preloaded = "none";
static void *doit(void *dummy)
{
char buf[] = "testlibs/libdummy-_.so.0"; /* replace char @ index 18 (_) */
char buf2[] = "testlib_dummy_get__"; /* replace char @ index 18 (_) */
void *hdl;
int *(*fn)();
int c;
int lastlib = -1;
int *ptr;
for (c = 0; c < sizeof(alphabet) - 1; c++) {
buf[18] = alphabet[c];
buf2[18] = alphabet[c];
hdl = dlopen(buf, RTLD_NOW | RTLD_GLOBAL);
if (!hdl) {
if (lastlib < 0) {
printf("ERROR[preloaded = %s]: couldn't load ANY library at all: %s\n", preloaded, dlerror());
break;
}
printf("%d\n", lastlib + 1);
break;
}
fn = (int *(*)())dlsym(hdl, buf2);
if (!fn) {
printf("ERROR[preloaded = %s]: symbol %s not found: %s\n", preloaded, buf2, dlerror());
break;
}
ptr = fn();
if (*ptr != 0) {
printf("ERROR[preloaded = %s]: function %s did not give expected result\n", preloaded, buf2);
break;
}
lastlib = c;
}
if (c == sizeof(alphabet) - 1)
printf("%d\n", lastlib + 1);
return dummy;
}
int main(int argc, char **argv)
{
int r;
pthread_t thread;
if (argc >= 2)
preloaded = argv[1];
r = pthread_create(&thread, NULL, doit, NULL);
if (r < 0) {
printf("ERROR[preloaded = %s]: could not create thread: %s\n", preloaded, strerror(errno));
return 1;
}
(void) pthread_join(thread, NULL);
return 0;
}
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