--- /dev/null
+/*
+ * Copyright (C) 2011 Red Hat, Inc.
+ *
+ * This 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.
+ *
+ * This 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 this library; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ */
+
+/*
+ * This is a helper for shunloadtest.c. This function is built into
+ * a shared library and linked with libvirto.so
+ *
+ * The function initializes libvirt and primes the thread local with
+ * an error which needs to be freed at thread exit
+ */
+
+#include <config.h>
+#include "internal.h"
+
+#include <libvirt/libvirt.h>
+#include <libvirt/virterror.h>
+#include <stdlib.h>
+
+static void shunloadError(void *userData ATTRIBUTE_UNUSED,
+ virErrorPtr error ATTRIBUTE_UNUSED)
+{
+}
+
+void shunloadStart(void);
+
+void shunloadStart(void) {
+ virConnectPtr conn;
+
+ virSetErrorFunc(NULL, shunloadError);
+ virInitialize();
+
+ conn = virConnectOpen("test:///default");
+ virDomainDestroy(NULL);
+ if (conn)
+ virConnectClose(conn);
+}
--- /dev/null
+/*
+ * Copyright (C) 2011 Red Hat, Inc.
+ *
+ * This 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.
+ *
+ * This 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 this library; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ */
+
+/*
+ * When libvirt initializes, it creates a thread local for storing
+ * the last virErrorPtr instance. It also registers a cleanup
+ * callback for the thread local that will be invoked whenever
+ * a thread exits.
+ *
+ * If the libvirt.so library was dlopen()'d and is dlclose()'d
+ * while there is still a thread present, then when that thread
+ * later exits, the libvirt cleanup callback will be invoked.
+ * Unfortunately libvirt.so will no longer be in memory so the
+ * callback SEGVs (if you're lucky), or invokes unlreated
+ * code at the same address as the old callback (if you're
+ * unlucky).
+ *
+ * To fix the problem libvirt is linked '-z nodelete' which
+ * prevents the code being removed from memory at dlclose().
+ *
+ * This test case demonstrates this SEGV scenario. If this
+ * test does not SEGV, then the '-z nodelete' fix is working
+ */
+
+#include <config.h>
+
+#ifdef linux
+
+# include <dlfcn.h>
+# include <pthread.h>
+# include <stdbool.h>
+# include <stdio.h>
+# include <unistd.h>
+# include <signal.h>
+
+# include "internal.h"
+# include "ignore-value.h"
+# include "testutils.h"
+
+pthread_cond_t cond = PTHREAD_COND_INITIALIZER;
+pthread_mutex_t lock = PTHREAD_MUTEX_INITIALIZER;
+bool running = false;
+bool quit = false;
+
+static void *threadMain(void *arg)
+{
+ void (*startup)(void) = arg;
+
+ startup();
+
+ pthread_mutex_lock(&lock);
+ running = true;
+ pthread_cond_signal(&cond);
+
+ while (!quit) {
+ pthread_cond_wait(&cond, &lock);
+ }
+ pthread_mutex_unlock(&lock);
+
+ return NULL;
+}
+
+static void sigHandler(int sig)
+{
+ ignore_value(write(STDERR_FILENO, "FAIL\n", 5));
+ signal(sig, SIG_DFL);
+ raise(sig);
+}
+
+/* We're not using the testutils.c main() wrapper because
+ * we don't want 'shunloadtest' itself to link against
+ * libvirt.so. We need to test dlopen()'ing of libvirt.so
+ */
+int main(int argc ATTRIBUTE_UNUSED, char **argv)
+{
+ void (*startup)(void);
+ pthread_t t;
+ void *lib;
+ char *theprogname;
+
+ theprogname = argv[0];
+ if (STRPREFIX(theprogname, "./"))
+ theprogname += 2;
+
+ fprintf(stderr, "TEST: %s\n", theprogname);
+ fprintf(stderr, " .%*s 1 ", 39, "");
+ signal(SIGSEGV, sigHandler);
+
+ if (!(lib = dlopen("./.libs/libshunload.so", RTLD_NOW))) {
+ fprintf(stderr, "Cannot load ./.libs/libshunload.so %s\n", dlerror());
+ return 1;
+ }
+ if (!(startup = dlsym(lib, "shunloadStart"))) {
+ fprintf(stderr, "Cannot find shunloadStart %s\n", dlerror());
+ return 1;
+ }
+
+ /*
+ * Create a thread which is going to initialize libvirt
+ * and raise an error
+ */
+ pthread_create(&t, NULL, threadMain, startup);
+
+ /* Wait for the thread to start and call libvirt */
+ pthread_mutex_lock(&lock);
+ while (!running) {
+ pthread_cond_wait(&cond, &lock);
+ }
+
+ /* Close the shared library (and thus make libvirt.so
+ * non-resident */
+ dlclose(lib);
+
+ /* Tell the thread to quit */
+ quit = true;
+ pthread_cond_signal(&cond);
+ pthread_mutex_unlock(&lock);
+
+ pthread_join(t, NULL);
+
+ /* If we got to here the thread successfully exited without
+ * causing a SEGV !
+ */
+
+ fprintf(stderr, "OK\n");
+
+ return 0;
+}
+
+#else
+
+int main(void)
+{
+ return EXIT_AM_SKIP;
+}
+
+#endif
projects / libvirt.git / commitdiff