1 files changed, 78 insertions, 0 deletions
diff --git a/src/basic/inotify-util.c b/src/basic/inotify-util.c
new file mode 100644
index 0000000..ee9b416
--- /dev/null
+++ b/src/basic/inotify-util.c
@@ -0,0 +1,78 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#include "fd-util.h"
+#include "inotify-util.h"
+#include "stat-util.h"
+
+bool inotify_event_next(
+                union inotify_event_buffer *buffer,
+                size_t size,
+                struct inotify_event **iterator,
+                int log_level) {
+
+        struct inotify_event *e;
+        size_t offset = 0;
+
+        assert(buffer);
+        assert(iterator);
+
+        if (*iterator) {
+                assert((uint8_t*) *iterator >= buffer->raw);
+                offset = (uint8_t*) *iterator - buffer->raw;
+                offset += offsetof(struct inotify_event, name) + (*iterator)->len;
+        }
+
+        if (size == offset)
+                return false; /* reached end of list */
+
+        if (size < offset ||
+            size - offset < offsetof(struct inotify_event, name)) {
+                log_full(log_level, "Received invalid inotify event, ignoring.");
+                return false;
+        }
+
+        e = CAST_ALIGN_PTR(struct inotify_event, buffer->raw + offset);
+        if (size - offset - offsetof(struct inotify_event, name) < e->len) {
+                log_full(log_level, "Received invalid inotify event, ignoring.");
+                return false;
+        }
+
+        *iterator = e;
+        return true;
+}
+
+int inotify_add_watch_fd(int fd, int what, uint32_t mask) {
+        int wd, r;
+
+        /* This is like inotify_add_watch(), except that the file to watch is not referenced by a path, but by an fd */
+        wd = inotify_add_watch(fd, FORMAT_PROC_FD_PATH(what), mask);
+        if (wd < 0) {
+                if (errno != ENOENT)
+                        return -errno;
+
+                /* Didn't work with ENOENT? If so, then either /proc/ isn't mounted, or the fd is bad */
+                r = proc_mounted();
+                if (r == 0)
+                        return -ENOSYS;
+                if (r > 0)
+                        return -EBADF;
+
+                return -ENOENT; /* OK, no clue, let's propagate the original error */
+        }
+
+        return wd;
+}
+
+int inotify_add_watch_and_warn(int fd, const char *pathname, uint32_t mask) {
+        int wd;
+
+        wd = inotify_add_watch(fd, pathname, mask);
+        if (wd < 0) {
+                if (errno == ENOSPC)
+                        return log_error_errno(errno, "Failed to add a watch for %s: inotify watch limit reached", pathname);
+
+                return log_error_errno(errno, "Failed to add a watch for %s: %m", pathname);
+        }
+
+        return wd;
+}