inotify-util: declare iterator in FOREACH_INOTIFY_EVENT()

This also makes the macro check if the event is actually in the buffer,
and if it is not, then log about that and finish the loop.

src/basic/inotify-util.h

@@ -6,12 +6,31 @@
 #include <stddef.h>
 #include <sys/inotify.h>
 
+#include "log.h"
+
 #define INOTIFY_EVENT_MAX (offsetof(struct inotify_event, name) + NAME_MAX + 1)
 
-#define FOREACH_INOTIFY_EVENT(e, 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))
+#define _FOREACH_INOTIFY_EVENT(e, buffer, sz, log_level, start, end)    \
+        for (struct inotify_event                                       \
+                            *start = &((buffer).ev),                    \
+                     *end = (struct inotify_event*) ((uint8_t*) start + (sz)), \
+                     *e = start;                                        \
+             (uint8_t*) e + sizeof(struct inotify_event) <= (uint8_t*) end && \
+             (uint8_t*) e + sizeof(struct inotify_event) + e->len <= (uint8_t*) end ? true : \
+                     ({                                                 \
+                             log_full(log_level, "Received invalid inotify event, ignoring."); \
+                             false;                                     \
+                     });                                                \
+             e = (struct inotify_event*) ((uint8_t*) e + sizeof(struct inotify_event) + e->len))
+
+#define _FOREACH_INOTIFY_EVENT_FULL(e, buffer, sz, log_level)           \
+        _FOREACH_INOTIFY_EVENT(e, buffer, sz, log_level, UNIQ_T(start, UNIQ), UNIQ_T(end, UNIQ))
+
+#define FOREACH_INOTIFY_EVENT(e, buffer, sz)                    \
+        _FOREACH_INOTIFY_EVENT_FULL(e, buffer, sz, LOG_DEBUG)
+
+#define FOREACH_INOTIFY_EVENT_WARN(e, buffer, sz)               \
+        _FOREACH_INOTIFY_EVENT_FULL(e, buffer, sz, LOG_WARNING)
 
 union inotify_event_buffer {
         struct inotify_event ev;

src/basic/terminal-util.c

@@ -432,7 +432,6 @@ int acquire_terminal(
 
                 for (;;) {
                         union inotify_event_buffer buffer;
-                        struct inotify_event *e;
                         ssize_t l;
 
                         if (timeout != USEC_INFINITY) {