From 8142ffa4d9a22163e82b07dd073c043cf12ed175 Mon Sep 17 00:00:00 2001
From: Eli Barzilay <eli@barzilay.org>
Date: Fri, 5 Aug 2011 01:08:21 -0400
Subject: [PATCH] Return a file size string when possible.

This takes the advice from
  http://files.stairways.com/other/ftp-list-specs-info.txt
further: search for the date by an explicit occurrence of a known month
name.  This means that we won't see files with bad names (they'd be
filtered out of the result), but the filtered out entries are ones that
would not be usable with `ftp-make-file-seconds'.

When the month is found, and the entry is a file, look for a number
preceding the month, and if found, return it as the file size string.
This is a minor change in the API.  (But it's probably better to either
revise it further, or eventually make it irrelevant by exposing the
interesting functionality via `net/url'.)

original commit: 6a1336e75edff75b7fc8a22a31d776acadc536eb
---
 collects/net/ftp-unit.rkt | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/collects/net/ftp-unit.rkt b/collects/net/ftp-unit.rkt
index 1f4aa70..7a80f7c 100644
--- a/collects/net/ftp-unit.rkt
+++ b/collects/net/ftp-unit.rkt
@@ -159,7 +159,9 @@
                       #"250" void (void)))
 
 (define re:dir-line
-  #rx"^(.)......... .* ([A-Z].* .* [0-9][0-9]:?[0-9][0-9]) (.*)$")
+  (regexp (string-append
+           "^(.)(.*) ((?i:jan|feb|mar|apr|may|jun|jul|aug|sep|oct|nov|dec)"
+           " .* [0-9][0-9]:?[0-9][0-9]) (.*)$")))
 
 (define (ftp-directory-list tcp-ports)
   (define tcp-data (establish-data-connection tcp-ports))
@@ -173,9 +175,15 @@
                       (ftp-connection-out tcp-ports)
                       #"226" print-msg (void))
   (for*/list ([l (in-list lines)]
-              [m (in-value (regexp-match re:dir-line l))]
+              [m (in-value (cond [(regexp-match re:dir-line l) => cdr]
+                                 [else #f]))]
               #:when m)
-    (cdr m)))
+    (define size (cond [(and (equal? "-" (car m))
+                             (regexp-match #rx"([0-9]+) *$" (cadr m)))
+                        => cadr]
+                       [else #f]))
+    (define r `(,(car m) ,@(cddr m)))
+    (if size `(,@r ,size) r)))
 
 (define (ftp-download-file tcp-ports folder filename)
   ;; Save the file under the name tmp.file, rename it once download is