1 /* Test support for single-thread optimizations. No threads, static dlopen. 2 Copyright (C) 2020-2022 Free Software Foundation, Inc. 3 This file is part of the GNU C Library. 4 5 The GNU C Library is free software; you can redistribute it and/or 6 modify it under the terms of the GNU Lesser General Public 7 License as published by the Free Software Foundation; either 8 version 2.1 of the License, or (at your option) any later version. 9 10 The GNU C Library is distributed in the hope that it will be useful, 11 but WITHOUT ANY WARRANTY; without even the implied warranty of 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 13 Lesser General Public License for more details. 14 15 You should have received a copy of the GNU Lesser General Public 16 License along with the GNU C Library; if not, see 17 <https://www.gnu.org/licenses/>. */ 18 19 /* In a static dlopen scenario, the single-threaded optimization is 20 not possible because their is no globally shared dynamic linker 21 across all namespaces. */ 22 23 #include <stddef.h> 24 #include <support/check.h> 25 #include <support/xdlfcn.h> 26 #include <sys/single_threaded.h> 27 28 static int do_test(void)29do_test (void) 30 { 31 TEST_VERIFY (__libc_single_threaded); 32 33 /* Defined in tst-single-threaded-mod1.o. */ 34 extern _Bool single_threaded_1 (void); 35 TEST_VERIFY (single_threaded_1 ()); 36 37 /* A failed dlopen does not change the multi-threaded status. */ 38 TEST_VERIFY (dlopen ("tst-single_threaded-does-not-exist.so", RTLD_LAZY) 39 == NULL); 40 TEST_VERIFY (__libc_single_threaded); 41 TEST_VERIFY (single_threaded_1 ()); 42 43 /* And neither does a successful dlopen for outer (static) libc. */ 44 void *handle_mod2 = xdlopen ("tst-single_threaded-mod2.so", RTLD_LAZY); 45 _Bool (*single_threaded_2) (void) 46 = xdlsym (handle_mod2, "single_threaded_2"); 47 TEST_VERIFY (__libc_single_threaded); 48 TEST_VERIFY (single_threaded_1 ()); 49 /* The inner libc always assumes multi-threaded use. */ 50 TEST_VERIFY (!single_threaded_2 ()); 51 52 xdlclose (handle_mod2); 53 54 return 0; 55 } 56 57 #include <support/test-driver.c> 58