db/update/{Walk,ExcludeList}: use InputStream to read .mpdignore

Supports .mpdignore on NFS/SMB and others (closes #290).

src/db/update/ExcludeList.cxx

@@ -26,8 +26,8 @@
 #include "ExcludeList.hxx"
 #include "fs/Path.hxx"
 #include "fs/NarrowPath.hxx"
-#include "fs/io/TextFile.hxx"
-#include "system/Error.hxx"
+#include "input/TextInputStream.hxx"
+#include "util/StringUtil.hxx"
 #include "Log.hxx"
 
 #include <stdexcept>
@@ -44,13 +44,13 @@ ExcludeList::ParseLine(char *line) noexcept
 }
 
 bool
-ExcludeList::LoadFile(Path path_fs) noexcept
-try {
+ExcludeList::Load(InputStreamPtr is)
+{
 #ifdef HAVE_CLASS_GLOB
-	TextFile file(path_fs);
+	TextInputStream tis(std::move(is));
 
 	char *line;
-	while ((line = file.ReadLine()) != nullptr)
+	while ((line = tis.ReadLine()) != nullptr)
 		ParseLine(line);
 #else
 	/* not implemented */
@@ -58,13 +58,6 @@ try {
 #endif
 
 	return true;
-} catch (const std::system_error &e) {
-	if (!IsFileNotFound(e))
-		LogError(e);
-	return false;
-} catch (const std::exception &e) {
-	LogError(e);
-	return false;
 }
 
 bool

src/db/update/ExcludeList.hxx

@@ -28,6 +28,7 @@
 #include "check.h"
 #include "Compiler.h"
 #include "fs/Glob.hxx"
+#include "input/Ptr.hxx"
 
 #ifdef HAVE_CLASS_GLOB
 #include <forward_list>
@@ -62,7 +63,7 @@ public:
 	/**
 	 * Loads and parses a .mpdignore file.
 	 */
-	bool LoadFile(Path path_fs) noexcept;
+	bool Load(InputStreamPtr is);
 
 	/**
 	 * Checks whether one of the patterns in the .mpdignore file matches

src/db/update/Walk.cxx

@@ -36,6 +36,9 @@
 #include "fs/Traits.hxx"
 #include "fs/FileSystem.hxx"
 #include "storage/FileInfo.hxx"
+#include "input/InputStream.hxx"
+#include "input/Error.hxx"
+#include "thread/Cond.hxx"
 #include "util/Alloc.hxx"
 #include "util/StringCompare.hxx"
 #include "util/UriUtil.hxx"
@@ -345,11 +348,16 @@ UpdateWalk::UpdateDirectory(Directory &directory,
 
 	ExcludeList child_exclude_list(exclude_list);
 
-	{
-		const auto exclude_path_fs =
-			storage.MapChildFS(directory.GetPath(), ".mpdignore");
-		if (!exclude_path_fs.IsNull())
-			child_exclude_list.LoadFile(exclude_path_fs);
+	try {
+		Mutex mutex;
+		Cond cond;
+		auto is = InputStream::OpenReady(PathTraitsUTF8::Build(storage.MapUTF8(directory.GetPath()).c_str(),
+								       ".mpdignore").c_str(),
+						 mutex, cond);
+		child_exclude_list.Load(std::move(is));
+	} catch (...) {
+		if (!IsFileNotFound(std::current_exception()))
+			LogError(std::current_exception());
 	}
 
 	if (!child_exclude_list.IsEmpty())