Add std::streambuf wrapper around SDL_RWops for boost

Also add SDL_RWops version of the readFile utility function.

binding-mri/binding-mri.cpp

@@ -25,6 +25,7 @@
 #include "eventthread.h"
 #include "filesystem.h"
 #include "util.h"
+#include "sdl-util.h"
 #include "debugwriter.h"
 #include "graphics.h"
 #include "audio.h"
@@ -339,7 +340,7 @@ static void runCustomScript(const std::string &filename)
 {
 	std::string scriptData;
 
-	if (!readFile(filename.c_str(), scriptData))
+	if (!readFileSDL(filename.c_str(), scriptData))
 	{
 		showMsg(std::string("Unable to open '") + filename + "'");
 		return;

src/config.cpp

@@ -32,6 +32,7 @@
 
 #include "debugwriter.h"
 #include "util.h"
+#include "sdl-util.h"
 
 #ifdef INI_ENCODING
 extern "C" {
@@ -223,22 +224,19 @@ void Config::read(int argc, char *argv[])
 	}
 
 	/* Parse configuration file */
-	std::ifstream confFile;
+	SDLRWStream confFile(CONF_FILE, "r");
-	confFile.open(CONF_FILE);
 
 	if (confFile)
 	{
 		try
 		{
-			po::store(po::parse_config_file(confFile, podesc, true), vm);
+			po::store(po::parse_config_file(confFile.stream(), podesc, true), vm);
 			po::notify(vm);
 		}
 		catch (po::error &error)
 		{
 			Debug() << CONF_FILE":" << error.what();
 		}
-
-		confFile.close();
 	}
 
 #undef PO_DESC
@@ -306,16 +304,25 @@ void Config::readGameINI()
 	        ("Game.Scripts", po::value<std::string>())
 	        ;
 
-	std::string iniPath = gameFolder + "/Game.ini";
-
-	std::ifstream iniFile;
-	iniFile.open((iniPath).c_str());
-
 	po::variables_map vm;
-	po::store(po::parse_config_file(iniFile, podesc, true), vm);
+	SDLRWStream iniFile("Game.ini", "r");
-	po::notify(vm);
 
-	iniFile.close();
+	if (iniFile)
+	{
+		try
+		{
+			po::store(po::parse_config_file(iniFile.stream(), podesc, true), vm);
+			po::notify(vm);
+		}
+		catch (po::error &error)
+		{
+			Debug() << "Game.ini:" << error.what();
+		}
+	}
+	else
+	{
+		Debug() << "FAILED to open Game.ini";
+	}
 
 	GUARD_ALL( game.title = vm["Game.Title"].as<std::string>(); );
 	GUARD_ALL( game.scripts = vm["Game.Scripts"].as<std::string>(); );

src/sdl-util.h

@@ -3,8 +3,10 @@
 
 #include <SDL_atomic.h>
 #include <SDL_thread.h>
+#include <SDL_rwops.h>
 
 #include <string>
+#include <iostream>
 
 struct AtomicFlag
 {
@@ -45,4 +47,99 @@ SDL_Thread *createSDLThread(C *obj, const std::string &name = std::string())
 	return SDL_CreateThread(__sdlThreadFun<C, func>, name.c_str(), obj);
 }
 
+inline bool readFileSDL(const char *path,
+                        std::string &out)
+{
+	SDL_RWops *f = SDL_RWFromFile(path, "rb");
+
+	if (!f)
+		return false;
+
+	long size = SDL_RWsize(f);
+	size_t back = out.size();
+
+	out.resize(back+size);
+	size_t read = SDL_RWread(f, &out[back], 1, size);
+	SDL_RWclose(f);
+
+	if (read != (size_t) size)
+		out.resize(back+read);
+
+	return true;
+}
+
+template<size_t bufSize = 248, size_t pbSize = 8>
+class SDLRWBuf : public std::streambuf
+{
+public:
+	SDLRWBuf(SDL_RWops *ops)
+	    : ops(ops)
+	{
+		char *end = buf + bufSize + pbSize;
+		setg(end, end, end);
+	}
+
+private:
+	int_type underflow()
+	{
+		if (!ops)
+			return traits_type::eof();
+
+		if (gptr() < egptr())
+			return traits_type::to_int_type(*gptr());
+
+		char *base = buf;
+		char *start = base;
+
+		if (eback() == base)
+		{
+			memmove(base, egptr() - pbSize, pbSize);
+			start += pbSize;
+		}
+
+		size_t n = SDL_RWread(ops, start, 1, bufSize - (start - base));
+		if (n == 0)
+			return traits_type::eof();
+
+		setg(base, start, start + n);
+
+		return underflow();
+	}
+
+	SDL_RWops *ops;
+	char buf[bufSize+pbSize];
+};
+
+class SDLRWStream
+{
+public:
+	SDLRWStream(const char *filename,
+	            const char *mode)
+	    : ops(SDL_RWFromFile(filename, mode)),
+	      buf(ops),
+	      s(&buf)
+	{}
+
+	~SDLRWStream()
+	{
+		if (ops)
+			SDL_RWclose(ops);
+	}
+
+	operator bool() const
+	{
+		return ops != 0;
+	}
+
+	std::istream &stream()
+	{
+		return s;
+	}
+
+private:
+	SDL_RWops *ops;
+	SDLRWBuf<> buf;
+	std::istream s;
+};
+
 #endif // SDLUTIL_H