/* Copyright (C) 2006-2022 Free Software Foundation, Inc. This file is part of the GNU C Library. The GNU C Library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. The GNU C Library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with the GNU C Library; if not, see <https://www.gnu.org/licenses/>. */ #include <errno.h> #include <stdlib.h> #include <stdio.h> #include <ucontext.h> #include <assert.h> #include <unwind.h> #include <dlfcn.h> #include <gnu/lib-names.h> ucontext_t ucp; char st1[16384]; __thread int thr; int somevar = -76; long othervar = -78L; struct trace_arg { int cnt, size; }; static _Unwind_Reason_Code backtrace_helper (struct _Unwind_Context *ctx, void *a) { struct trace_arg *arg = a; if (++arg->cnt == arg->size) return _URC_END_OF_STACK; return _URC_NO_REASON; } void cf (int i) { struct trace_arg arg = { .size = 100, .cnt = -1 }; void *handle; _Unwind_Reason_Code (*unwind_backtrace) (_Unwind_Trace_Fn, void *); if (i != othervar || thr != 94) { printf ("i %d thr %d\n", i, thr); exit (1); } /* Test if callback function of _Unwind_Backtrace is not called infinitely times. See Bug 18508 or gcc bug "Bug 66303 - runtime.Caller() returns infinitely deep stack frames on s390x.". The go runtime calls backtrace_full() in <gcc-src>/libbacktrace/backtrace.c, which uses _Unwind_Backtrace(). */ handle = dlopen (LIBGCC_S_SO, RTLD_LAZY); if (handle != NULL) { unwind_backtrace = dlsym (handle, "_Unwind_Backtrace"); if (unwind_backtrace != NULL) { unwind_backtrace (backtrace_helper, &arg); assert (arg.cnt != -1 && arg.cnt < 100); } dlclose (handle); } /* Since uc_link below has been set to NULL, setcontext is supposed to terminate the process normally after this function returns. */ } int do_test (void) { if (getcontext (&ucp) != 0) { if (errno == ENOSYS) { puts ("context handling not supported"); return 0; } puts ("getcontext failed"); return 1; } thr = 94; ucp.uc_link = NULL; ucp.uc_stack.ss_sp = st1; ucp.uc_stack.ss_size = sizeof st1; makecontext (&ucp, (void (*) (void)) cf, 1, somevar - 2); if (setcontext (&ucp) != 0) { puts ("setcontext failed"); return 1; } return 2; } #define TEST_FUNCTION do_test () #include "../test-skeleton.c"