From 461967af6834fb0fccdd39a8d76192d411223148 Mon Sep 17 00:00:00 2001
From: Mikko Rasa <tdb@tdb.fi>
Date: Sun, 19 Oct 2014 20:33:05 +0300
Subject: [PATCH] Support adding packs from IO::Seekable objects

This allows using any seekable objects as packs, such as Android assets.
---
 source/packsource.cpp | 38 +++++++++++++++++++++++++++++++-------
 source/packsource.h   | 13 ++++++++++++-
 2 files changed, 43 insertions(+), 8 deletions(-)

diff --git a/source/packsource.cpp b/source/packsource.cpp
index 00af3ad..938a627 100644
--- a/source/packsource.cpp
+++ b/source/packsource.cpp
@@ -24,6 +24,16 @@ void PackSource::add_pack_file(const string &fn)
 }
 
 void PackSource::add_pack_file(const string &fn, const string &filter)
+{
+	add_pack(0, fn, filter);
+}
+
+void PackSource::add_pack_io(IO::Seekable &io, const string &fn)
+{
+	add_pack(&io, fn, string());
+}
+
+void PackSource::add_pack(IO::Seekable *io, const string &fn, const string &filter)
 {
 	Pack *pack = 0;
 	for(list<Pack>::iterator i=packs.begin(); (!pack && i!=packs.end()); ++i)
@@ -31,9 +41,16 @@ void PackSource::add_pack_file(const string &fn, const string &filter)
 			pack = &*i;
 	if(!pack)
 	{
-		packs.push_back(Pack(fn));
+		packs.push_back(Pack(io, fn));
 		pack = &packs.back();
-		DataFile::load(*pack, fn);
+		if(io)
+		{
+			DataFile::Parser parser(*io, fn);
+			Pack::Loader loader(*pack);
+			loader.load(parser);
+		}
+		else
+			DataFile::load(*pack, fn);
 	}
 
 	FileMap pack_files;
@@ -115,8 +132,9 @@ IO::Seekable *PackSource::open(const string &fn) const
 }
 
 
-PackSource::Pack::Pack(const string &fn):
+PackSource::Pack::Pack(IO::Seekable *i, const string &fn):
 	filename(fn),
+	io(i),
 	base_offset(0)
 { }
 
@@ -148,10 +166,16 @@ PackSource::File::File(const Pack &p, const string &fn):
 
 RefPtr<IO::Seekable> PackSource::File::open() const
 {
-	IO::BufferedFile *io_file = new IO::BufferedFile(pack.get_filename());
-	IO::Slice *io_slice = new IO::Slice(*io_file, pack.get_base_offset()+offset, length);
-	io_slice->signal_deleted.connect(sigc::bind(sigc::ptr_fun(delete_io), io_file));
-	return io_slice;
+	if(pack.get_io())
+		// TODO Performance may be poor without buffering
+		return new IO::Slice(*pack.get_io(), pack.get_base_offset()+offset, length);
+	else
+	{
+		IO::BufferedFile *io_file = new IO::BufferedFile(pack.get_filename());
+		IO::Slice *io_slice = new IO::Slice(*io_file, pack.get_base_offset()+offset, length);
+		io_slice->signal_deleted.connect(sigc::bind(sigc::ptr_fun(delete_io), io_file));
+		return io_slice;
+	}
 }
 
 PackSource::FileInfo PackSource::File::get_info() const
diff --git a/source/packsource.h b/source/packsource.h
index a599b5c..440b451 100644
--- a/source/packsource.h
+++ b/source/packsource.h
@@ -48,13 +48,15 @@ private:
 
 	private:
 		std::string filename;
+		IO::Seekable *io;
 		unsigned base_offset;
 		std::list<File> files;
 
 	public:
-		Pack(const std::string &);
+		Pack(IO::Seekable *, const std::string &);
 
 		const std::string &get_filename() const { return filename; }
+		IO::Seekable *get_io() const { return io; }
 		unsigned get_base_offset() const { return base_offset; }
 
 		void collect_files(FileMap &, const std::string &) const;
@@ -123,6 +125,15 @@ public:
 	read on the first call; subsequent calls will use cached data. */
 	void add_pack_file(const std::string &, const std::string &);
 
+	/** Adds a pack from an existing seekable I/O object.  The same object is
+	used for all accesses to the pack, so it must not be deleted before the
+	PackSource. */
+	void add_pack_io(IO::Seekable &, const std::string & = std::string());
+
+private:
+	void add_pack(IO::Seekable *, const std::string &, const std::string &);
+
+public:
 	/// Returns information about the files in the pack.
 	std::list<FileInfo> list_files() const;
 
-- 
2.43.0