Fix: Add pointer check when freeing poll events

[lttng-tools.git] / src / common / compat / poll.h

diff --git a/src/common/compat/poll.h b/src/common/compat/poll.h
index 6dca76d81827324f3767efc90bd06948a7b22fba..cfde4fc8381d36786f23683de1ffa7cc3f9e40f8 100644 (file)
--- a/src/common/compat/poll.h
+++ b/src/common/compat/poll.h
@@ -1,18 +1,18 @@
 /*
  * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
  *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License as published by the Free
- * Software Foundation; only version 2 of the License.
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2 only,
+ * as published by the Free Software Foundation.
  *
  * This program 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 General Public License for
  * more details.
  *
- * You should have received a copy of the GNU General Public License along with
- * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
- * Place - Suite 330, Boston, MA  02111-1307, USA.
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  */
 
 #ifndef _LTT_POLL_H
@@ -42,7 +42,9 @@ extern unsigned int poll_max_size;
  */
 static inline void __lttng_poll_free(void *events)
 {
-       free(events);
+       if (events) {
+               free(events);
+       }
 }
 
 /*
@@ -50,6 +52,7 @@ static inline void __lttng_poll_free(void *events)
  */
 #ifdef HAVE_EPOLL
 #include <sys/epoll.h>
+#include <stdio.h>
 
 /* See man epoll(7) for this define path */
 #define COMPAT_EPOLL_PROC_PATH "/proc/sys/fs/epoll/max_user_watches"
@@ -95,7 +98,7 @@ struct compat_epoll_event {
 extern int compat_epoll_create(struct lttng_poll_event *events,
                int size, int flags);
 #define lttng_poll_create(events, size, flags) \
-       compat_epoll_create(events, size, flags);
+       compat_epoll_create(events, size, flags)
 
 /*
  * Wait on epoll set with the number of fd registered to the lttng_poll_event
@@ -103,7 +106,7 @@ extern int compat_epoll_create(struct lttng_poll_event *events,
  */
 extern int compat_epoll_wait(struct lttng_poll_event *events, int timeout);
 #define lttng_poll_wait(events, timeout) \
-       compat_epoll_wait(events, timeout);
+       compat_epoll_wait(events, timeout)
 
 /*
  * Add a fd to the epoll set and resize the epoll_event structure if needed.
@@ -111,21 +114,21 @@ extern int compat_epoll_wait(struct lttng_poll_event *events, int timeout);
 extern int compat_epoll_add(struct lttng_poll_event *events,
                int fd, uint32_t req_events);
 #define lttng_poll_add(events, fd, req_events) \
-       compat_epoll_add(events, fd, req_events);
+       compat_epoll_add(events, fd, req_events)
 
 /*
  * Remove a fd from the epoll set.
  */
 extern int compat_epoll_del(struct lttng_poll_event *events, int fd);
 #define lttng_poll_del(events, fd) \
-       compat_epoll_del(events, fd);
+       compat_epoll_del(events, fd)
 
 /*
  * Set up the poll set limits variable poll_max_size
  */
 extern void compat_epoll_set_max_size(void);
-#define lttng_poll_set_max_size(void) \
-       compat_epoll_set_max_size(void);
+#define lttng_poll_set_max_size() \
+       compat_epoll_set_max_size()
 
 /*
  * This function memset with zero the structure since it can be reused at each
@@ -146,8 +149,13 @@ static inline void lttng_poll_reset(struct lttng_poll_event *events)
  */
 static inline void lttng_poll_clean(struct lttng_poll_event *events)
 {
+       int ret;
+
        if (events) {
-               close(events->epfd);
+               ret = close(events->epfd);
+               if (ret) {
+                       perror("close");
+               }
                __lttng_poll_free((void *) events->events);
        }
 }
@@ -179,10 +187,17 @@ enum {
        LPOLLRDBAND = POLLRDBAND,
        LPOLLWRNORM = POLLWRNORM,
        LPOLLWRBAND = POLLWRBAND,
+#if __linux__
        LPOLLMSG = POLLMSG,
+       LPOLLRDHUP = POLLRDHUP,
+#elif (defined(__FreeBSD__) || defined(__CYGWIN__))
+       LPOLLMSG = 0,
+       LPOLLRDHUP = 0,
+#else
+#error "Please add support for your OS."
+#endif /* __linux__ */
        LPOLLERR = POLLERR,
        LPOLLHUP = POLLHUP | POLLNVAL,
-       LPOLLRDHUP = POLLRDHUP,
        /* Close on exec feature does not exist for poll(2) */
        LTTNG_CLOEXEC = 0xdead,
 };
@@ -208,7 +223,7 @@ struct compat_poll_event {
  */
 extern int compat_poll_create(struct lttng_poll_event *events, int size);
 #define lttng_poll_create(events, size, flags) \
-       compat_poll_create(events, size);
+       compat_poll_create(events, size)
 
 /*
  * Wait on poll(2) event with nb_fd registered to the lttng_poll_event data
@@ -216,7 +231,7 @@ extern int compat_poll_create(struct lttng_poll_event *events, int size);
  */
 extern int compat_poll_wait(struct lttng_poll_event *events, int timeout);
 #define lttng_poll_wait(events, timeout) \
-       compat_poll_wait(events, timeout);
+       compat_poll_wait(events, timeout)
 
 /*
  * Add the fd to the pollfd structure. Resize if needed.
@@ -224,7 +239,7 @@ extern int compat_poll_wait(struct lttng_poll_event *events, int timeout);
 extern int compat_poll_add(struct lttng_poll_event *events,
                int fd, uint32_t req_events);
 #define lttng_poll_add(events, fd, req_events) \
-       compat_poll_add(events, fd, req_events);
+       compat_poll_add(events, fd, req_events)
 
 /*
  * Remove the fd from the pollfd. Memory allocation is done to recreate a new
@@ -233,14 +248,14 @@ extern int compat_poll_add(struct lttng_poll_event *events,
  */
 extern int compat_poll_del(struct lttng_poll_event *events, int fd);
 #define lttng_poll_del(events, fd) \
-       compat_poll_del(events, fd);
+       compat_poll_del(events, fd)
 
 /*
  * Set up the poll set limits variable poll_max_size
  */
 extern void compat_poll_set_max_size(void);
-#define lttng_poll_set_max_size(void) \
-       compat_poll_set_max_size(void);
+#define lttng_poll_set_max_size() \
+       compat_poll_set_max_size()
 
 /*
  * No need to reset a pollfd structure for poll(2)