Rename helper providers and events for consistency

[lttng-ust.git] / liblttng-ust-dl / lttng-ust-dl.c

diff --git a/liblttng-ust-dl/lttng-ust-dl.c b/liblttng-ust-dl/lttng-ust-dl.c
new file mode 100644 (file)
index 0000000..13d2b43
--- /dev/null
+++ b/liblttng-ust-dl/lttng-ust-dl.c
@@ -0,0 +1,111 @@
+/*
+ * Copyright (C) 2013  Paul Woegerer <paul.woegerer@mentor.com>
+ *
+ * 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; version 2.1 of
+ * the License.
+ *
+ * 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., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301 USA
+ */
+
+#define _LGPL_SOURCE
+#define _GNU_SOURCE
+#include <lttng/ust-dlfcn.h>
+#include <inttypes.h>
+#include <link.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <limits.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <signal.h>
+#include <sched.h>
+#include <stdarg.h>
+#include "usterr-signal-safe.h"
+
+#include <lttng/ust-compiler.h>
+#include <lttng/ust.h>
+
+#define TRACEPOINT_DEFINE
+#include "ust_dl.h"
+
+static void *(*__lttng_ust_plibc_dlopen)(const char *filename, int flag);
+static int (*__lttng_ust_plibc_dlclose)(void *handle);
+
+static
+void *_lttng_ust_dl_libc_dlopen(const char *filename, int flag)
+{
+       if (!__lttng_ust_plibc_dlopen) {
+               __lttng_ust_plibc_dlopen = dlsym(RTLD_NEXT, "dlopen");
+               if (__lttng_ust_plibc_dlopen == NULL) {
+                       fprintf(stderr, "%s\n", dlerror());
+                       return NULL;
+               }
+       }
+       return __lttng_ust_plibc_dlopen(filename, flag);
+}
+
+static
+int _lttng_ust_dl_libc_dlclose(void *handle)
+{
+       if (!__lttng_ust_plibc_dlclose) {
+               __lttng_ust_plibc_dlclose = dlsym(RTLD_NEXT, "dlclose");
+               if (__lttng_ust_plibc_dlclose == NULL) {
+                       fprintf(stderr, "%s\n", dlerror());
+                       return -1;
+               }
+       }
+       return __lttng_ust_plibc_dlclose(handle);
+}
+
+static
+void lttng_ust_dl_dlopen(void *so_base, const char *so_name)
+{
+       char resolved_path[PATH_MAX];
+       struct stat sostat;
+
+       if (!realpath(so_name, resolved_path)) {
+               ERR("could not resolve path '%s'", so_name);
+               return;
+       }
+
+       if (stat(resolved_path, &sostat)) {
+               ERR("could not access file status for %s", resolved_path);
+               return;
+       }
+
+       tracepoint(lttng_ust_dl, dlopen,
+               so_base, resolved_path, sostat.st_size, sostat.st_mtime);
+       return;
+}
+
+void *dlopen(const char *filename, int flag)
+{
+       void *handle = _lttng_ust_dl_libc_dlopen(filename, flag);
+       if (__tracepoint_ptrs_registered && handle) {
+               struct link_map *p = NULL;
+               if (dlinfo(handle, RTLD_DI_LINKMAP, &p) != -1 && p != NULL
+                               && p->l_addr != 0)
+                       lttng_ust_dl_dlopen((void *) p->l_addr, p->l_name);
+       }
+       return handle;
+}
+
+int dlclose(void *handle)
+{
+       if (__tracepoint_ptrs_registered && handle) {
+               struct link_map *p = NULL;
+               if (dlinfo(handle, RTLD_DI_LINKMAP, &p) != -1 && p != NULL
+                               && p->l_addr != 0)
+                       tracepoint(lttng_ust_dl, dlclose, (void *) p->l_addr);
+       }
+       return _lttng_ust_dl_libc_dlclose(handle);
+}