udev: move udev_rules_check_timestamp to shared

I want to use this from a bulitin in a subsequent patch.

2 files changed, 34 insertions, 0 deletions

diff --git a/src/shared/path-util.c b/src/shared/path-util.c
index 45099eeda8..def7a7409a 100644
--- a/src/shared/path-util.c
+++ b/src/shared/path-util.c
@@ -473,3 +473,34 @@ int find_binary(const char *name, char **filename) {
                 return -ENOENT;
         }
 }
+
+bool paths_check_timestamp(char **paths, usec_t *paths_ts_usec, bool update)
+{
+        unsigned int i;
+        bool changed = false;
+
+        if (paths == NULL)
+                goto out;
+
+        for (i = 0; paths[i]; i++) {
+                struct stat stats;
+
+                if (stat(paths[i], &stats) < 0)
+                        continue;
+
+                if (paths_ts_usec[i] == timespec_load(&stats.st_mtim))
+                        continue;
+
+                /* first check */
+                if (paths_ts_usec[i] != 0) {
+                        log_debug("reload - timestamp of '%s' changed\n", paths[i]);
+                        changed = true;
+                }
+
+                /* update timestamp */
+                if (update)
+                        paths_ts_usec[i] = timespec_load(&stats.st_mtim);
+        }
+out:
+        return changed;
+}
diff --git a/src/shared/path-util.h b/src/shared/path-util.h
index 0a42de7e27..42b4189d77 100644
--- a/src/shared/path-util.h
+++ b/src/shared/path-util.h
@@ -24,6 +24,7 @@
 #include <stdbool.h>
 
 #include "macro.h"
+#include "time-util.h"
 
 #ifdef HAVE_SPLIT_USR
 #  define DEFAULT_PATH "/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin"
@@ -52,6 +53,8 @@ int path_is_os_tree(const char *path);
 
 int find_binary(const char *name, char **filename);
 
+bool paths_check_timestamp(char **paths, usec_t *paths_ts_usec, bool update);
+
 /* Iterates through the path prefixes of the specified path, going up
  * the tree, to root. Also returns "" (and not "/"!) for the root
  * directory. Excludes the specified directory itself */