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Index: lib/libc/Versions.def
===================================================================
--- lib/libc/Versions.def
+++ lib/libc/Versions.def
@@ -27,6 +27,10 @@
FBSD_1.4 {
} FBSD_1.3;
+# This version was first added to 12.0-current.
+FBSD_1.5 {
+} FBSD_1.4;
+
# This is our private namespace. Any global interfaces that are
# strictly for use only by other FreeBSD applications and libraries
@@ -35,4 +39,4 @@
#
# Please do NOT increment the version of this namespace.
FBSDprivate_1.0 {
-} FBSD_1.4;
+} FBSD_1.5;
Index: lib/libc/include/libc_private.h
===================================================================
--- lib/libc/include/libc_private.h
+++ lib/libc/include/libc_private.h
@@ -267,6 +267,12 @@
void _malloc_thread_cleanup(void);
/*
+ * This function is used by the threading libraries to notify libc that a
+ * thread is exiting, so its thread-local dtors should be called.
+ */
+void __cxa_thread_call_dtors(void);
+
+/*
* These functions are used by the threading libraries in order to protect
* malloc across fork().
*/
Index: lib/libc/stdlib/Makefile.inc
===================================================================
--- lib/libc/stdlib/Makefile.inc
+++ lib/libc/stdlib/Makefile.inc
@@ -5,7 +5,7 @@
.PATH: ${LIBC_SRCTOP}/${LIBC_ARCH}/stdlib ${LIBC_SRCTOP}/stdlib
MISRCS+=_Exit.c a64l.c abort.c abs.c atexit.c atof.c atoi.c atol.c atoll.c \
- bsearch.c div.c exit.c getenv.c getopt.c getopt_long.c \
+ bsearch.c cxa_thread_atexit.c div.c exit.c getenv.c getopt.c getopt_long.c \
getsubopt.c hcreate.c hcreate_r.c hdestroy_r.c heapsort.c heapsort_b.c \
hsearch_r.c imaxabs.c imaxdiv.c \
insque.c l64a.c labs.c ldiv.c llabs.c lldiv.c lsearch.c \
Index: lib/libc/stdlib/Symbol.map
===================================================================
--- lib/libc/stdlib/Symbol.map
+++ lib/libc/stdlib/Symbol.map
@@ -116,8 +116,13 @@
reallocarray;
};
+FBSD_1.5 {
+ __cxa_thread_atexit;
+};
+
FBSDprivate_1.0 {
__system;
_system;
__libc_system;
+ __cxa_thread_call_dtors;
};
Index: lib/libc/stdlib/cxa_thread_atexit.c
===================================================================
--- /dev/null
+++ lib/libc/stdlib/cxa_thread_atexit.c
@@ -0,0 +1,126 @@
+/*-
+ * Copyright (c) 2016 Mahdi Mokhtari <mokhi64@gmail.com>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/queue.h>
+#include "namespace.h"
+#include <errno.h>
+#include <link.h>
+#include <pthread.h>
+#include <stddef.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include "un-namespace.h"
+#include "libc_private.h"
+
+/*
+ * C++11 introduces the thread_local scope (like __thread with some
+ * additions). As a key-feature it should support non-trivial
+ * destructors, registered with __cxa_thread_atexit() to be executed
+ * at the thread termination.
+ *
+ *The idea of implementing this is to keep a _Thread_local list of
+ * destructors per each thread, and calling __cxa_thread_call_dtors()
+ * on each thread's exit to do cleanup. For a thread calling exit(3),
+ * in particular, for the initial thread returning from main(), we'll
+ * call __cxa_thread_call_dtors() inside exit().
+ *
+ * It could be possible that a dynamically loaded library, use
+ * thread_local variable but is dlclose()'d before thread exit. The
+ * destructor of this variable will then try to access the address,
+ * for calling it but it's unloaded, so it'll crash. We're using
+ * __elf_phdr_match_addr() to detect and prevent such cases and so
+ * prevent the crash.
+ */
+
+#define CXA_DTORS_ITERATIONS 4
+
+struct cxa_thread_dtor {
+ void *obj;
+ void (*func)(void *);
+ void *dso;
+ LIST_ENTRY(cxa_thread_dtor) entry;
+};
+static _Thread_local LIST_HEAD(dtor_list, cxa_thread_dtor) dtors =
+ LIST_HEAD_INITIALIZER(dtors);
+
+int
+__cxa_thread_atexit(void (*dtor_func)(void *), void *obj, void *dso_symbol)
+{
+ struct cxa_thread_dtor *new_dtor;
+
+ new_dtor = malloc(sizeof(*new_dtor));
+ if (new_dtor == NULL)
+ return (ENOMEM);
+
+ new_dtor->obj = obj;
+ new_dtor->func = dtor_func;
+ new_dtor->dso = dso_symbol;
+ LIST_INSERT_HEAD(&dtors, new_dtor, entry);
+ return (0);
+}
+
+/*
+ * This is the callback function we use to call destructors, once for
+ * each thread. It is called in exit(3) in libc/stdlib/exit.c and
+ * before exit_thread() in libthr/thread/thr_exit.c.
+ */
+void
+__cxa_thread_call_dtors(void)
+{
+ struct cxa_thread_dtor *dtor, *tdtor;
+ struct dl_phdr_info phdr_info;
+ int i;
+
+ for (i = 0; i < CXA_DTORS_ITERATIONS; ++i) {
+ LIST_FOREACH_SAFE(dtor, &dtors, entry, tdtor) {
+ LIST_REMOVE(dtor, entry);
+ if (_rtld_addr_phdr(dtor->dso, &phdr_info) &&
+ __elf_phdr_match_addr(&phdr_info, dtor->func))
+ dtor->func(dtor->obj);
+ else
+ fprintf(stderr, "__cxa_thread_call_dtors: "
+ "dtr %p from unloaded dso, skipping\n",
+ (void *)(dtor->func));
+ free(dtor);
+ }
+ if (LIST_EMPTY(&dtors))
+ break;
+ }
+
+ if (!LIST_EMPTY(&dtors)) {
+ fprintf(stderr, "Thread %p is exiting with more "
+ "thread-specific dtors created after %d iterations "
+ "of destructor calls\n",
+ _pthread_self(), i);
+ LIST_FOREACH_SAFE(dtor, &dtors, entry, tdtor) {
+ LIST_REMOVE(dtor, entry);
+ free(dtor);
+ }
+ }
+}
Index: lib/libc/stdlib/exit.c
===================================================================
--- lib/libc/stdlib/exit.c
+++ lib/libc/stdlib/exit.c
@@ -63,6 +63,12 @@
_thread_autoinit_dummy_decl = 1;
+ /*
+ * We're dealing with cleaning up thread_local destructors in the case of
+ * the process termination through main() exit.
+ * Other cases are handled elsewhere.
+ */
+ __cxa_thread_call_dtors();
__cxa_finalize(NULL);
if (__cleanup)
(*__cleanup)();
Index: lib/libc/tests/stdlib/Makefile
===================================================================
--- lib/libc/tests/stdlib/Makefile
+++ lib/libc/tests/stdlib/Makefile
@@ -4,6 +4,8 @@
ATF_TESTS_C+= mergesort_test
ATF_TESTS_C+= qsort_test
ATF_TESTS_C+= tsearch_test
+ATF_TESTS_CXX+= cxa_thread_atexit_test
+ATF_TESTS_CXX+= cxa_thread_atexit_nothr_test
# TODO: t_getenv_thread, t_mi_vector_hash
NETBSD_ATF_TESTS_C+= abs_test
@@ -33,6 +35,10 @@
CFLAGS+= -I${.CURDIR}
+CXXFLAGS.cxa_thread_atexit_test+= -std=c++11
+CXXFLAGS.cxa_thread_atexit_nothr_test+= -std=c++11
+LIBADD.cxa_thread_atexit_test+= pthread
+
.for t in h_getopt h_getopt_long
CFLAGS.$t+= -I${LIBNETBSD_SRCDIR} -I${SRCTOP}/contrib/netbsd-tests
LDFLAGS.$t+= -L${LIBNETBSD_OBJDIR}
Index: lib/libc/tests/stdlib/Makefile.depend
===================================================================
--- lib/libc/tests/stdlib/Makefile.depend
+++ lib/libc/tests/stdlib/Makefile.depend
@@ -8,7 +8,10 @@
include/xlocale \
lib/${CSU_DIR} \
lib/atf/libatf-c \
+ lib/atf/libatf-c++ \
lib/libc \
+ lib/libc++ \
+ lib/libthr \
lib/libcompiler_rt \
lib/libnetbsd \
lib/libutil \
Index: lib/libc/tests/stdlib/cxa_thread_atexit_nothr_test.cc
===================================================================
--- /dev/null
+++ lib/libc/tests/stdlib/cxa_thread_atexit_nothr_test.cc
@@ -0,0 +1,102 @@
+/*-
+ * Copyright (c) 2016 Mahdi Mokhtari <mokhi64@gmail.com>
+ * Copyright (c) 2016 The FreeBSD Foundation
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <dlfcn.h>
+#include <atf-c++.hpp>
+#include <cstdio>
+#include <cstdlib>
+
+static FILE *output = NULL;
+
+struct Foo {
+ Foo() { ATF_REQUIRE(fprintf(output, "Created\n") > 0); }
+ ~Foo() { ATF_REQUIRE(fprintf(output, "Destroyed\n") > 0); }
+ void use() { ATF_REQUIRE(fprintf(output, "Used\n") > 0); }
+};
+
+static thread_local Foo f;
+
+/*
+ * This test must not be linked to libpthread.
+ */
+ATF_TEST_CASE_WITHOUT_HEAD(cxx__nothr);
+ATF_TEST_CASE_BODY(cxx__nothr)
+{
+ void *libthr_handle;
+
+ /* Avoid coredump during f construction. */
+ output = stderr;
+
+ libthr_handle = dlopen("libthr.so.3", RTLD_LAZY | RTLD_GLOBAL |
+ RTLD_NOLOAD);
+ ATF_REQUIRE(libthr_handle == NULL);
+}
+
+static void
+check_local_main(void)
+{
+ static const char out_log[] = "Created\nUsed\nDestroyed\n";
+
+ fflush(output);
+ ATF_REQUIRE(atf::utils::compare_file("test_main.txt", out_log));
+}
+
+ATF_TEST_CASE_WITHOUT_HEAD(cxx__thread_local_main);
+ATF_TEST_CASE_BODY(cxx__thread_local_main)
+{
+
+ ATF_REQUIRE((output = fopen("test_main.txt", "w")) != NULL);
+ f.use();
+ atexit(check_local_main);
+}
+
+extern "C" int __cxa_thread_atexit(void (*)(void *), void *, void *);
+
+static void
+again(void *arg)
+{
+
+ __cxa_thread_atexit(again, arg, &output);
+}
+
+ATF_TEST_CASE_WITHOUT_HEAD(cxx__thread_inf_dtors);
+ATF_TEST_CASE_BODY(cxx__thread_inf_dtors)
+{
+
+ again(NULL);
+}
+
+ATF_INIT_TEST_CASES(tcs)
+{
+
+ ATF_ADD_TEST_CASE(tcs, cxx__nothr);
+ ATF_ADD_TEST_CASE(tcs, cxx__thread_local_main);
+ ATF_ADD_TEST_CASE(tcs, cxx__thread_inf_dtors);
+}
Index: lib/libc/tests/stdlib/cxa_thread_atexit_test.cc
===================================================================
--- /dev/null
+++ lib/libc/tests/stdlib/cxa_thread_atexit_test.cc
@@ -0,0 +1,180 @@
+/*-
+ * Copyright (c) 2016 Mahdi Mokhtari <mokhi64@gmail.com>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <dlfcn.h>
+#include <atf-c++.hpp>
+#include <cstdio>
+#include <cstdlib>
+#include <thread>
+
+static FILE *output = NULL;
+
+struct Foo {
+ Foo() { ATF_REQUIRE(fprintf(output, "Created\n") > 0); }
+ ~Foo() { ATF_REQUIRE(fprintf(output, "Destroyed\n") > 0); }
+ void use() { ATF_REQUIRE(fprintf(output, "Used\n") > 0); }
+};
+
+struct Bar {
+ Bar() {}
+ ~Bar() {
+ thread_local static Foo foo;
+ ATF_REQUIRE(fprintf(output, "DIED\n") > 0);
+ }
+ void use() {}
+};
+
+extern "C" int __cxa_thread_atexit(void (*)(void *), void *, void *);
+
+static void
+again(void *arg)
+{
+
+ __cxa_thread_atexit(again, arg, &output);
+}
+
+struct Baz {
+ Baz() {}
+ ~Baz() {
+ again(NULL);
+ }
+ void use() {}
+};
+
+static thread_local Foo f;
+static thread_local Foo g;
+static thread_local Bar h;
+static thread_local Baz e;
+
+/*
+ * This test must be linked to libpthread.
+ */
+ATF_TEST_CASE_WITHOUT_HEAD(cxx__thr);
+ATF_TEST_CASE_BODY(cxx__thr)
+{
+ void *libthr_handle;
+
+ /* Avoid coredump during f construction. */
+ output = stderr;
+
+ libthr_handle = dlopen("libthr.so.3", RTLD_LAZY | RTLD_GLOBAL |
+ RTLD_NOLOAD);
+ ATF_REQUIRE(libthr_handle != NULL);
+ dlclose(libthr_handle);
+}
+
+/*
+ * In this test f.use() will test cxa_thread_atexit() in non-threaded mode.
+ * After f.use() main will be threaded and we'll have one additional thread
+ * with its own TLS data.
+ */
+ATF_TEST_CASE_WITHOUT_HEAD(cxx__thread_local_before);
+ATF_TEST_CASE_BODY(cxx__thread_local_before)
+{
+ static const char out_log[] = "Created\nCreated\nUsed\nCreated\n"
+ "Created\nUsed\nCreated\nDIED\nDestroyed\nDestroyed\nDestroyed\n";
+
+ ATF_REQUIRE((output = fopen("test_before.txt", "w")) != NULL);
+
+ f.use();
+ std::thread t([]() { f.use(); });
+ t.join();
+
+ fflush(output);
+
+ ATF_REQUIRE(atf::utils::compare_file("test_before.txt", out_log));
+}
+
+/*
+ * In this test, f.use() will test __cxa_thread_atexit()
+ * in threaded mode (but still in main-threaed).
+ */
+ATF_TEST_CASE_WITHOUT_HEAD(cxx__thread_local_after);
+ATF_TEST_CASE_BODY(cxx__thread_local_after)
+{
+ static const char out_log[] = "Created\nCreated\nUsed\nCreated\n"
+ "DIED\nDestroyed\nDestroyed\nDestroyed\nCreated\nCreated\nUsed\n";
+
+ ATF_REQUIRE((output = fopen("test_after.txt", "w")) != NULL);
+
+ std::thread t([]() { g.use(); });
+ t.join();
+ sleep(1);
+ g.use();
+
+ fflush(output);
+
+ ATF_REQUIRE(atf::utils::compare_file("test_after.txt", out_log));
+}
+
+/*
+ * In this test, we register a new dtor while dtors are being run
+ * in __cxa_thread_atexit().
+ */
+ATF_TEST_CASE_WITHOUT_HEAD(cxx__thread_local_add_while_calling_dtors);
+ATF_TEST_CASE_BODY(cxx__thread_local_add_while_calling_dtors)
+{
+ static const char out_log[] = "Created\nCreated\nCreated\nDIED\n"
+ "Destroyed\nDestroyed\nDestroyed\n";
+
+ ATF_REQUIRE((output = fopen("test_add_meanwhile.txt", "w")) != NULL);
+
+ std::thread t([]() { h.use(); });
+ t.join();
+ sleep(1);
+
+ fflush(output);
+
+ ATF_REQUIRE(atf::utils::compare_file("test_add_meanwhile.txt", out_log));
+}
+
+ATF_TEST_CASE_WITHOUT_HEAD(cxx__thread_inf_dtors);
+ATF_TEST_CASE_BODY(cxx__thread_inf_dtors)
+{
+
+ /*
+ * Only added to make isolated run of this test not
+ * coredumping. Construction of Foo objects require filled
+ * output.
+ */
+ output = stderr;
+
+ std::thread t([]() { e.use(); });
+ t.join();
+}
+
+ATF_INIT_TEST_CASES(tcs)
+{
+
+ ATF_ADD_TEST_CASE(tcs, cxx__thr);
+ ATF_ADD_TEST_CASE(tcs, cxx__thread_local_before);
+ ATF_ADD_TEST_CASE(tcs, cxx__thread_local_after);
+ ATF_ADD_TEST_CASE(tcs, cxx__thread_local_add_while_calling_dtors);
+ ATF_ADD_TEST_CASE(tcs, cxx__thread_inf_dtors);
+}
Index: lib/libthr/thread/thr_exit.c
===================================================================
--- lib/libthr/thread/thr_exit.c
+++ lib/libthr/thread/thr_exit.c
@@ -153,8 +153,12 @@
__pthread_cleanup_pop_imp(1);
}
- if (done)
+ if (done) {
+ /* Tell libc that it should call non-trivial TLS dtors. */
+ __cxa_thread_call_dtors();
+
exit_thread(); /* Never return! */
+ }
return (_URC_NO_REASON);
}
@@ -258,6 +262,8 @@
while (curthread->cleanup != NULL) {
__pthread_cleanup_pop_imp(1);
}
+ __cxa_thread_call_dtors();
+
exit_thread();
}
@@ -265,6 +271,7 @@
while (curthread->cleanup != NULL) {
__pthread_cleanup_pop_imp(1);
}
+ __cxa_thread_call_dtors();
exit_thread();
#endif /* _PTHREAD_FORCED_UNWIND */

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