opus conversie

private/scan.rkt

@@ -1,12 +1,39 @@
 #lang racket/base
 
-(require racket/file
-         racket/list
+(require racket/list
+         racket/path
          "util.rkt")
 
-(provide find-flac-files)
+(provide find-flac-files
+         find-regular-files)
+
+(define (directory-list/quiet dir)
+  (with-handlers ([exn:fail? (lambda (_) '())])
+    (directory-list dir #:build? #t)))
+
+(define (directory-exists?/quiet p)
+  (with-handlers ([exn:fail? (lambda (_) #f)])
+    (directory-exists? p)))
+
+(define (file-exists?/quiet p)
+  (with-handlers ([exn:fail? (lambda (_) #f)])
+    (file-exists? p)))
+
+(define (sort-paths paths)
+  (sort paths string<? #:key path->string))
+
+(define (find-regular-files base-dir)
+  ;; Do not use racket/file:find-files here.  On Windows UNC trees, especially
+  ;; with long paths, fold-files can raise "path disappeared" for a single
+  ;; entry and abort the whole scan.  This walker treats entries that disappear,
+  ;; are inaccessible, or cannot be represented by the platform path layer as a
+  ;; skipped entry and continues the scan.
+  (define root (filesystem-path base-dir))
+  (let loop ([dir root] [acc '()])
+    (for/fold ([acc acc]) ([p (in-list (sort-paths (directory-list/quiet dir)))])
+      (cond [(directory-exists?/quiet p) (loop p acc)]
+            [(file-exists?/quiet p) (cons p acc)]
+            [else acc]))))
 
 (define (find-flac-files base-dir)
-  (sort (find-files flac-path? base-dir)
-        string<?
-        #:key path->string))
+  (sort-paths (filter flac-path? (find-regular-files base-dir))))