util: fix strict aliasing violations in use of struct inotify_event v5

There is alot of cleanup that will have to happen to turn on
-fstrict-aliasing, but I think our code should be "correct" to the rule.

Signed-off-by: Anthony G. Basile <blueness@gentoo.org>

3 files changed, 10 insertions, 5 deletions

diff --git a/src/shared/util.c b/src/shared/util.c
index e58e51561b..6ef53b05ef 100644
--- a/src/shared/util.c
+++ b/src/shared/util.c
@@ -37,7 +37,6 @@
 #include <linux/tiocl.h>
 #include <termios.h>
 #include <stdarg.h>
-#include <sys/inotify.h>
 #include <poll.h>
 #include <ctype.h>
 #include <sys/prctl.h>
diff --git a/src/shared/util.h b/src/shared/util.h
index 8cdb79cd8f..402203e0dd 100644
--- a/src/shared/util.h
+++ b/src/shared/util.h
@@ -31,6 +31,7 @@
 #include <stddef.h>
 #include <unistd.h>
 #include <sys/socket.h>
+#include <sys/inotify.h>
 
 #include "time-util.h"
 #include "missing.h"
@@ -463,6 +464,11 @@ int execute_command(const char *command, char *const argv[]);
 #define INOTIFY_EVENT_MAX (sizeof(struct inotify_event) + NAME_MAX + 1)
 
 #define FOREACH_INOTIFY_EVENT(e, buffer, sz) \
-        for ((e) = (struct inotify_event*) (buffer);    \
-             (uint8_t*) (e) < (uint8_t*) (buffer) + (sz); \
+        for ((e) = &buffer.ev;                                \
+             (uint8_t*) (e) < (uint8_t*) (buffer.raw) + (sz); \
              (e) = (struct inotify_event*) ((uint8_t*) (e) + sizeof(struct inotify_event) + (e)->len))
+
+union inotify_event_buffer {
+        struct inotify_event ev;
+        uint8_t raw[INOTIFY_EVENT_MAX];
+};
diff --git a/src/udev/udevd.c b/src/udev/udevd.c
index b519dc4c99..092fc95db3 100644
--- a/src/udev/udevd.c
+++ b/src/udev/udevd.c
@@ -807,11 +807,11 @@ static int synthesize_change(struct udev_device *dev) {
 }
 
 static int handle_inotify(struct udev *udev) {
-        uint8_t buffer[INOTIFY_EVENT_MAX] _alignas_(struct inotify_event);
+        union inotify_event_buffer buffer;
         struct inotify_event *e;
         ssize_t l;
 
-        l = read(fd_inotify, buffer, sizeof(buffer));
+        l = read(fd_inotify, &buffer, sizeof(buffer));
         if (l < 0) {
                 if (errno == EAGAIN || errno == EINTR)
                         return 0;