sd-device: remove debug log message when dirs are missing

This is a common case, and nothing noteworthy at all. For example, if we
establish an enumerator for listing all devices tagged by some tag, then
the per-tag dir is not going to exist if there are currently no devices
tagged that way, but that's a really common case, and doesn't really
deserve any mention, not even at debug level.

(cherry picked from commit a68c97a)
(cherry picked from commit 8aa9e60)
(cherry picked from commit a321caf)
(cherry picked from commit 32a3200)
(cherry picked from commit 9988e09)

Author: poettering

src/libsystemd/sd-device/device-enumerator.c

@@ -688,13 +688,11 @@ static int enumerator_scan_dir_and_add_devices(
 
         dir = opendir(path);
         if (!dir) {
-                bool ignore = errno == ENOENT;
+                /* This is necessarily racey, so ignore missing directories */
+                if (errno == ENOENT)
+                        return 0;
 
-                /* this is necessarily racey, so ignore missing directories */
-                log_debug_errno(errno,
-                                "sd-device-enumerator: Failed to open directory %s%s: %m",
-                                path, ignore ? ", ignoring" : "");
-                return ignore ? 0 : -errno;
+                return log_debug_errno(errno, "sd-device-enumerator: Failed to open directory '%s': %m", path);
         }
 
         FOREACH_DIRENT_ALL(de, dir, return -errno) {
@@ -754,12 +752,10 @@ static int enumerator_scan_dir(
 
         dir = opendir(path);
         if (!dir) {
-                bool ignore = errno == ENOENT;
+                if (errno == ENOENT)
+                        return 0;
 
-                log_debug_errno(errno,
-                                "sd-device-enumerator: Failed to open directory %s%s: %m",
-                                path, ignore ? ", ignoring" : "");
-                return ignore ? 0 : -errno;
+                return log_debug_errno(errno, "sd-device-enumerator: Failed to open directory '%s': %m", path);
         }
 
         FOREACH_DIRENT_ALL(de, dir, return -errno) {
@@ -791,12 +787,10 @@ static int enumerator_scan_devices_tag(sd_device_enumerator *enumerator, const c
 
         dir = opendir(path);
         if (!dir) {
-                bool ignore = errno == ENOENT;
+                if (errno == ENOENT)
+                        return 0;
 
-                log_debug_errno(errno,
-                                "sd-device-enumerator: Failed to open directory %s%s: %m",
-                                path, ignore ? ", ignoring" : "");
-                return ignore ? 0 : -errno;
+                return log_debug_errno(errno, "sd-device-enumerator: Failed to open directory '%s': %m", path);
         }
 
         /* TODO: filter away subsystems? */
@@ -879,12 +873,10 @@ static int parent_crawl_children(sd_device_enumerator *enumerator, const char *p
 
         dir = opendir(path);
         if (!dir) {
-                bool ignore = errno == ENOENT;
+                if (errno == ENOENT)
+                        return 0;
 
-                log_debug_errno(errno,
-                                "sd-device-enumerator: Failed to open directory %s%s: %m",
-                                path, ignore ? ", ignoring" : "");
-                return ignore ? 0 : -errno;
+                return log_debug_errno(errno, "sd-device-enumerator: Failed to open directory '%s': %m", path);
         }
 
         FOREACH_DIRENT_ALL(de, dir, return -errno) {