sleep: improve log msg slightly

Let's make the log msgs a bit longer, to make clearer what is going on
here...

Prompted bymy attempts to debug #15354

diff --git a/src/shared/sleep-config.c b/src/shared/sleep-config.c
index e63ef0f261b08752bfbeadf087146224b3415f86..6dbdff7b28155c0320e6faacb79750dd0c0c86fb 100644 (file)
--- a/src/shared/sleep-config.c
+++ b/src/shared/sleep-config.c
@@ -223,7 +223,7 @@ static int calculate_swap_file_offset(const SwapEntry *swap, uint64_t *ret_offse
 
         fd = open(swap->device, O_RDONLY|O_CLOEXEC|O_NOCTTY);
         if (fd < 0)
-                return log_error_errno(errno, "Failed to open %s: %m", swap->device);
+                return log_error_errno(errno, "Failed to open swap file %s to determine on-disk offset: %m", swap->device);
 
         if (fstat(fd, &sb) < 0)
                 return log_error_errno(errno, "Failed to stat %s: %m", swap->device);