love2d.love/src/modules/filesystem/wrap_File.cpp

/**
 * Copyright (c) 2006-2014 LOVE Development Team
 *
 * This software is provided 'as-is', without any express or implied
 * warranty.  In no event will the authors be held liable for any damages
 * arising from the use of this software.
 *
 * Permission is granted to anyone to use this software for any purpose,
 * including commercial applications, and to alter it and redistribute it
 * freely, subject to the following restrictions:
 *
 * 1. The origin of this software must not be misrepresented; you must not
 *    claim that you wrote the original software. If you use this software
 *    in a product, an acknowledgment in the product documentation would be
 *    appreciated but is not required.
 * 2. Altered source versions must be plainly marked as such, and must not be
 *    misrepresented as being the original software.
 * 3. This notice may not be removed or altered from any source distribution.
 **/

#include "wrap_File.h"

#include "physfs/Filesystem.h"

#include "common/Data.h"
#include "common/Exception.h"
#include "common/int.h"

namespace love
{
namespace filesystem
{

int luax_ioError(lua_State *L, const char *fmt, ...)
{
	va_list args;
	va_start(args, fmt);

	lua_pushnil(L);
	lua_pushvfstring(L, fmt, args);

	va_end(args);
	return 2;
}

File *luax_checkfile(lua_State *L, int idx)
{
	return luax_checktype<File>(L, idx, "File", FILESYSTEM_FILE_T);
}

int w_File_getSize(lua_State *L)
{
	File *t = luax_checkfile(L, 1);

	int64 size = -1;
	try
	{
		size = t->getSize();
	}
	catch (love::Exception &e)
	{
		return luax_ioError(L, "%s", e.what());
	}

	// Push nil on failure or if size does not fit into a double precision floating-point number.
	if (size == -1)
		return luax_ioError(L, "Could not determine file size.");
	else if (size >= 0x20000000000000LL)
		return luax_ioError(L, "Size is too large.");

	lua_pushnumber(L, (lua_Number) size);
	return 1;
}

int w_File_open(lua_State *L)
{
	File *file = luax_checkfile(L, 1);
	const char *str = luaL_checkstring(L, 2);
	File::Mode mode;

	if (!File::getConstant(str, mode))
		return luaL_error(L, "Incorrect file open mode: %s", str);

	try
	{
		luax_pushboolean(L, file->open(mode));
	}
	catch (love::Exception &e)
	{
		return luax_ioError(L, "%s", e.what());
	}

	return 1;
}

int w_File_close(lua_State *L)
{
	File *file = luax_checkfile(L, 1);
	luax_pushboolean(L, file->close());
	return 1;
}

int w_File_isOpen(lua_State *L)
{
	File *file = luax_checkfile(L, 1);
	luax_pushboolean(L, file->isOpen());
	return 1;
}

int w_File_read(lua_State *L)
{
	File *file = luax_checkfile(L, 1);
	Data *d = 0;

	int64 size = (int64)luaL_optnumber(L, 2, File::ALL);

	try
	{
		d = file->read(size);
	}
	catch (love::Exception &e)
	{
		return luax_ioError(L, "%s", e.what());
	}

	lua_pushlstring(L, (const char *) d->getData(), d->getSize());
	lua_pushnumber(L, d->getSize());
	d->release();
	return 2;
}

int w_File_write(lua_State *L)
{
	File *file = luax_checkfile(L, 1);
	bool result = false;

	if (lua_isstring(L, 2))
	{
		try
		{
			size_t datasize = 0;
			const char *data = lua_tolstring(L, 2, &datasize);

			if (!lua_isnoneornil(L, 3))
				datasize = luaL_checkinteger(L, 3);

			result = file->write(data, datasize);
		}
		catch (love::Exception &e)
		{
			return luax_ioError(L, "%s", e.what());
		}
	}
	else if (luax_istype(L, 2, DATA_T))
	{
		try
		{
			love::Data *data = luax_totype<love::Data>(L, 2, "Data", DATA_T);
			result = file->write(data, luaL_optinteger(L, 3, data->getSize()));
		}
		catch (love::Exception &e)
		{
			return luax_ioError(L, "%s", e.what());
		}
	}
	else
	{
		return luaL_argerror(L, 2, "string or data expected");
	}

	luax_pushboolean(L, result);
	return 1;
}

int w_File_flush(lua_State *L)
{
	File *file = luax_checkfile(L, 1);
	bool success = false;
	try
	{
		success = file->flush();
	}
	catch (love::Exception &e)
	{
		return luax_ioError(L, "%s", e.what());
	}
	luax_pushboolean(L, success);
	return 1;
}

int w_File_eof(lua_State *L)
{
	File *file = luax_checkfile(L, 1);
	luax_pushboolean(L, file->eof());
	return 1;
}

int w_File_tell(lua_State *L)
{
	File *file = luax_checkfile(L, 1);
	int64 pos = file->tell();
	// Push nil on failure or if pos does not fit into a double precision floating-point number.
	if (pos == -1)
		return luax_ioError(L, "Invalid position.");
	else if (pos >= 0x20000000000000LL)
		return luax_ioError(L, "Number is too large.");
	else
		lua_pushnumber(L, (lua_Number)pos);
	return 1;
}

int w_File_seek(lua_State *L)
{
	File *file = luax_checkfile(L, 1);
	lua_Number pos = luaL_checknumber(L, 2);

	// Push false on negative and precision-problematic numbers.
	// Better fail than seek to an unknown position.
	if (pos < 0.0 || pos >= 9007199254740992.0)
		luax_pushboolean(L, false);
	else
		luax_pushboolean(L, file->seek((uint64)pos));
	return 1;
}

int w_File_lines(lua_State *L)
{
	File *file = luax_checkfile(L, 1);

	lua_pushnumber(L, 0); // File position.
	luax_pushboolean(L, file->getMode() != File::CLOSED); // Save current file mode.

	if (file->getMode() != File::READ)
	{
		if (file->getMode() != File::CLOSED)
			file->close();

		bool success = false;
		EXCEPT_GUARD(success = file->open(File::READ);)

		if (!success)
			return luaL_error(L, "Could not open file.");
	}

	lua_pushcclosure(L, physfs::Filesystem::lines_i, 3);
	return 1;
}

int w_File_setBuffer(lua_State *L)
{
	File *file = luax_checkfile(L, 1);
	const char *str = luaL_checkstring(L, 2);
	int64 size = (int64) luaL_optnumber(L, 3, 0.0);

	File::BufferMode bufmode;
	if (!File::getConstant(str, bufmode))
		return luaL_error(L, "Incorrect file buffer mode: %s", str);

	bool success = false;
	try
	{
		success = file->setBuffer(bufmode, size);
	}
	catch (love::Exception &e)
	{
		return luax_ioError(L, "%s", e.what());
	}

	luax_pushboolean(L, success);
	return 1;
}

int w_File_getBuffer(lua_State *L)
{
	File *file = luax_checkfile(L, 1);
	int64 size = 0;
	File::BufferMode bufmode = file->getBuffer(size);
	const char *str = 0;

	if (!File::getConstant(bufmode, str))
		return luax_ioError(L, "Unknown file buffer mode.");

	lua_pushstring(L, str);
	lua_pushnumber(L, (lua_Number) size);
	return 2;
}

int w_File_getMode(lua_State *L)
{
	File *file = luax_checkfile(L, 1);

	File::Mode mode = file->getMode();
	const char *str = 0;

	if (!File::getConstant(mode, str))
		return luax_ioError(L, "Unknown file mode.");

	lua_pushstring(L, str);
	return 1;
}

static const luaL_Reg functions[] =
{
	{ "getSize", w_File_getSize },
	{ "open", w_File_open },
	{ "close", w_File_close },
	{ "isOpen", w_File_isOpen },
	{ "read", w_File_read },
	{ "write", w_File_write },
	{ "flush", w_File_flush },
	{ "eof", w_File_eof },
	{ "tell", w_File_tell },
	{ "seek", w_File_seek },
	{ "lines", w_File_lines },
	{ "setBuffer", w_File_setBuffer },
	{ "getBuffer", w_File_getBuffer },
	{ "getMode", w_File_getMode },
	{ 0, 0 }
};

extern "C" int luaopen_file(lua_State *L)
{
	return luax_register_type(L, "File", functions);
}

} // filesystem
} // love