blf: expand a comment.

Give more details on how the amount of padding between log container
objects is not an obvious "padd the object's size to a multiple of
<power of 2> bytes".

[skip ci]

diff --git a/wiretap/blf.c b/wiretap/blf.c
index ed927711fcf9fa9cf43e242071b4d9a80a322719..c8127349b394f6ff8ba032814d2663a5d14987cf 100644 (file)
--- a/wiretap/blf.c
+++ b/wiretap/blf.c
@@ -1048,8 +1048,16 @@ blf_scan_file_for_logcontainers(blf_params_t *params, int *err, gchar **err_info
                 break;
             }
 
-            /* we are moving back and try again but 1 byte later */
-            /* TODO: better understand how this paddings works... */
+            /*
+             * we are moving back and try again but 1 byte later
+             * TODO: better understand how this paddings works...
+             * Note that, in at least one capture - the Example.blf
+             * file attached to
+             * https://gitlab.com/wireshark/wireshark/-/issues/19269 -
+             * one of the log container objects is aligned on a 2-byte
+             * bundary but *not* on a 4-byte boundary, with 3 bytes
+             * of padding.
+             */
             current_start_pos++;
             if (file_seek(params->fh, current_start_pos, SEEK_SET, err) < 0) {
                 return FALSE;