slug.c

#include "a.h"

int mainstacksize=16384;
Mousectl *mc;
Keyboardctl *kc;
int drawing;

lua_State*
linit(int argc, char *argv[])
{
	lua_State *L;
	const char *s;
	int r;

	L = luaL_newstate();
	lua_gc(L, LUA_GCGEN, 0, 0);	
	lua_pushboolean(L, 1);
	lua_setfield(L, LUA_REGISTRYINDEX, "LUA_NOENV");
	luaL_openlibs(L);
	registerapi(L);
	registerpixels(L);
	initstate(L);
	r = luaL_dofile(L, argc > 1 ? argv[1] : NULL);
	if(r != LUA_OK){
		s = luaL_checkstring(L, lua_gettop(L));
		fprint(2, "error: %s\n", s);
	}
	return L;
}

int
lcallerror(lua_State *L)
{
	const char *m;

	m = lua_tostring(L, 1);
	if(m == nil){
		if(luaL_callmeta(L, 1, "__tostring") && lua_type(L, -1) == LUA_TSTRING)
			return 1;
		else
			m = lua_pushfstring(L, "(error object is a %s value)", luaL_typename(L, 1));
	}
	luaL_traceback(L, L, m, 1);
	return 1;
}	

void
lcall(lua_State *L, char *fn)
{
	int r, base;

	lua_getglobal(L, fn);
	if(!lua_isfunction(L, -1))
		return;
	base = lua_gettop(L);
	lua_pushcfunction(L, lcallerror);
	lua_insert(L, base);
	r = lua_pcall(L, 0, 0, base);
	lua_remove(L, base);
	if(r != LUA_OK){
		fprint(2, "%s\n", lua_tostring(L, -1));
		lua_pop(L, 1);
		threadexitsall("error");
	}
	drawcanvas();
}

void
lset(lua_State *L, const char *name, int value)
{
	lua_pushnumber(L, value);
	lua_setglobal(L, name);
}

void
resize(lua_State *L, int w, int h)
{
	int fd, n;
	char buf[255];

	fd = open("/dev/wctl", OWRITE|OCEXEC);
	if(fd < 0)
		sysfatal("open: %r");
	n = snprint(buf, sizeof buf, "resize -dx %d -dy %d", w, h);
	if(write(fd, buf, n) != n)
		fprint(2, "write error: %r\n");
	close(fd);
	lset(L, "width", w);
	lset(L, "height", h);
}

void
emouse(lua_State *L, Mouse m)
{
	Point xy;

	xy = subpt(m.xy, screen->r.min);
	xy = subpt(xy, origin);
	lset(L, "mouseX", xy.x);
	lset(L, "mouseY", xy.y);
}

void
threadmain(int argc, char *argv[])
{
	lua_State *L;
	vlong t0, t1;
	double delta;
	Mouse m;
	Rune k;
	Alt alts[] = {
		{ nil, &m, CHANRCV },
		{ nil, nil, CHANRCV },
		{ nil, &k,  CHANRCV },
		{ nil, nil, CHANNOBLK },
	};

	if(initdraw(nil, nil, "slug") < 0)
		sysfatal("initdraw: %r");
	display->locking = 0;
	if((mc = initmouse(nil, screen)) == nil)
		sysfatal("initmouse: %r");
	if((kc = initkeyboard(nil)) == nil)
		sysfatal("initkeyboard: %r");
	alts[0].c = mc->c;
	alts[1].c = mc->resizec;
	alts[2].c = kc->c;
	setfcr(getfcr() & ~(FPZDIV | FPOVFL | FPINVAL));	
	L = linit(argc, argv);
	resize(L, width, height);
	drawing = 0;
	lcall(L, "setup");
	drawing = 1;
	for(;;){
		if(looping){
			reset();
			t0 = nsec();
			lcall(L, "draw");
			t1 = nsec();
			delta = (t1 - t0) / 1000000.0;
			if(delta > 0.0)
				sleep((1000.0 / framerate) - delta);
		}
		switch(alt(alts)){
		case 0:
			emouse(L, m);
			break;
		case 1:
			if(getwindow(display, Refnone)<0)
				sysfatal("getwindow: %r");
			resize(L, width, height);
			drawcanvas();
			break;
		case 2:
			if(k == Kdel)
				goto Done;
			break;
		}
	}
Done:
	lua_close(L);
	threadexitsall(nil);
}