update: apply .mpdignore matches to subdirectories

Wildcard matches are directly applied to all filenames in
subdirectories without any attempt at matching relative paths.

This change is based on the following feature request:

  http://bugs.musicpd.org/view.php?id=3729

NEWS

@@ -36,6 +36,8 @@ ver 0.20 (not yet released)
 * support libsystemd (instead of the older libsystemd-daemon)
 * database
   - proxy: add TCP keepalive option
+* update
+  - apply .mpdignore matches to subdirectories
 
 ver 0.19.10 (2015/06/21)
 * input

doc/user.xml

@@ -1077,6 +1077,8 @@ database {
         To exclude a file from the update, create a file called
         <filename>.mpdignore</filename> in its parent directory.  Each
         line of that file may contain a list of shell wildcards.
+        Matching files in the current directory and all subdirectories
+        are excluded.
       </para>
     </section>
 

src/db/update/ExcludeList.cxx

@@ -89,6 +89,12 @@ ExcludeList::Check(Path name_fs) const
 	/* XXX include full path name in check */
 
 #ifdef HAVE_CLASS_GLOB
+	if (parent != nullptr) {
+		if (parent->Check(name_fs)) {
+			return true;
+		}
+	}
+
 	for (const auto &i : patterns)
 		if (i.Check(NarrowPath(name_fs).c_str()))
 			return true;

src/db/update/ExcludeList.hxx

@@ -36,15 +36,23 @@
 class Path;
 
 class ExcludeList {
+	const ExcludeList *const parent;
+
 #ifdef HAVE_CLASS_GLOB
 	std::forward_list<Glob> patterns;
 #endif
 
 public:
+	ExcludeList()
+		:parent(nullptr) {}
+
+	ExcludeList(const ExcludeList &_parent)
+		:parent(&_parent) {}
+
 	gcc_pure
 	bool IsEmpty() const {
 #ifdef HAVE_CLASS_GLOB
-		return patterns.empty();
+		return ((parent == nullptr) || parent->IsEmpty()) && patterns.empty();
 #else
 		/* not implemented */
 		return true;

src/db/update/Walk.cxx

@@ -219,6 +219,7 @@ UpdateWalk::UpdateRegularFile(Directory &directory,
 
 void
 UpdateWalk::UpdateDirectoryChild(Directory &directory,
+				 const ExcludeList &exclude_list,
 				 const char *name, const StorageFileInfo &info)
 {
 	assert(strchr(name, '/') == nullptr);
@@ -236,7 +237,7 @@ UpdateWalk::UpdateDirectoryChild(Directory &directory,
 
 		assert(&directory == subdir->parent);
 
-		if (!UpdateDirectory(*subdir, info))
+		if (!UpdateDirectory(*subdir, exclude_list, info))
 			editor.LockDeleteDirectory(subdir);
 	} else {
 		FormatDebug(update_domain,
@@ -327,7 +328,9 @@ UpdateWalk::SkipSymlink(const Directory *directory,
 }
 
 bool
-UpdateWalk::UpdateDirectory(Directory &directory, const StorageFileInfo &info)
+UpdateWalk::UpdateDirectory(Directory &directory,
+			    const ExcludeList &exclude_list,
+			    const StorageFileInfo &info)
 {
 	assert(info.IsDirectory());
 
@@ -340,17 +343,17 @@ UpdateWalk::UpdateDirectory(Directory &directory, const StorageFileInfo &info)
 		return false;
 	}
 
-	ExcludeList exclude_list;
+	ExcludeList child_exclude_list(exclude_list);
 
 	{
 		const auto exclude_path_fs =
 			storage.MapChildFS(directory.GetPath(), ".mpdignore");
 		if (!exclude_path_fs.IsNull())
-			exclude_list.LoadFile(exclude_path_fs);
+			child_exclude_list.LoadFile(exclude_path_fs);
 	}
 
-	if (!exclude_list.IsEmpty())
+	if (!child_exclude_list.IsEmpty())
-		RemoveExcludedFromDirectory(directory, exclude_list);
+		RemoveExcludedFromDirectory(directory, child_exclude_list);
 
 	PurgeDeletedFromDirectory(directory);
 
@@ -361,7 +364,7 @@ UpdateWalk::UpdateDirectory(Directory &directory, const StorageFileInfo &info)
 
 		{
 			const auto name_fs = AllocatedPath::FromUTF8(name_utf8);
-			if (name_fs.IsNull() || exclude_list.Check(name_fs))
+			if (name_fs.IsNull() || child_exclude_list.Check(name_fs))
 				continue;
 		}
 
@@ -376,7 +379,7 @@ UpdateWalk::UpdateDirectory(Directory &directory, const StorageFileInfo &info)
 			continue;
 		}
 
-		UpdateDirectoryChild(directory, name_utf8, info2);
+		UpdateDirectoryChild(directory, child_exclude_list, name_utf8, info2);
 	}
 
 	directory.mtime = info.mtime;
@@ -468,7 +471,9 @@ UpdateWalk::UpdateUri(Directory &root, const char *uri)
 		return;
 	}
 
-	UpdateDirectoryChild(*parent, name, info);
+	ExcludeList exclude_list;
+
+	UpdateDirectoryChild(*parent, exclude_list, name, info);
 }
 
 bool
@@ -484,7 +489,9 @@ UpdateWalk::Walk(Directory &root, const char *path, bool discard)
 		if (!GetInfo(storage, "", info))
 			return false;
 
-		UpdateDirectory(root, info);
+		ExcludeList exclude_list;
+
+		UpdateDirectory(root, exclude_list, info);
 	}
 
 	return modified;

src/db/update/Walk.hxx

@@ -129,10 +129,12 @@ private:
 			       const char *name, const StorageFileInfo &info);
 
 	void UpdateDirectoryChild(Directory &directory,
+				  const ExcludeList &exclude_list,
 				  const char *name,
 				  const StorageFileInfo &info);
 
 	bool UpdateDirectory(Directory &directory,
+			     const ExcludeList &exclude_list,
 			     const StorageFileInfo &info);
 
 	/**