added support for error handlers and implemented a REPL

8 files changed, 223 insertions, 7 deletions

diff --git a/Makefile b/Makefile
index 58c74e0..1625863 100644
--- a/Makefile
+++ b/Makefile
@@ -8,11 +8,12 @@ LUA_VERSION = 5.1
 DESTDIR     =
 PREFIX      = /usr/local
 BINDIR      = $(PREFIX)/bin
-LIBDIR      = $(PREFIX)/lib/lua/$(LUA_VERSION)/lem
+LIBDIR      = $(PREFIX)/lib/lua/$(LUA_VERSION)
 INCDIR      = $(PREFIX)/include
 
-programs = lem utils.so
 headers  = lem.h config.h macros.h lua/luaconf.h lua/lua.h lua/lauxlib.h libev/ev.h
+programs = lem utils.so
+scripts  = repl.lua lem-repl
 
 ifdef NDEBUG
 DEFINES += -DNDEBUG
@@ -80,6 +81,10 @@ lem-install: lem bindir-install
 	$Mecho "  INSTALL $<"
 	$O$(INSTALL) $< $(DESTDIR)$(BINDIR)/$<
 
+lem-repl-install: lem-repl bindir-install
+	$Mecho "  INSTALL $<"
+	$O$(INSTALL) $< $(DESTDIR)$(BINDIR)/$<
+
 incdir-install:
 	$Mecho "  INSTALL -d $(INCDIR)/lem"
 	$O$(INSTALL) -d $(DESTDIR)$(INCDIR)/lem
@@ -94,13 +99,17 @@ lem.h-install: lem.h incdir-install
 
 libdir-install:
 	$Mecho "  INSTALL -d $(LIBDIR)"
-	$O$(INSTALL) -d $(DESTDIR)$(LIBDIR)
+	$O$(INSTALL) -d $(DESTDIR)$(LIBDIR)/lem
 
 %.so-install: %.so libdir-install
 	$Mecho "  INSTALL $<"
-	$O$(INSTALL) $< $(DESTDIR)$(LIBDIR)/$<
+	$O$(INSTALL) $< $(DESTDIR)$(LIBDIR)/lem/$<
+
+%.lua-install: %.lua libdir-install
+	$Mecho "  INSTALL $<"
+	$O$(INSTALL) $< $(DESTDIR)$(LIBDIR)/lem/$<
 
-install: $(programs:%=%-install) $(headers:%=%-install)
+install: $(headers:%=%-install) $(programs:%=%-install) $(scripts:%=%-install)
 
 clean:
 	rm -f config.h $(programs) *.o lua/*.o *.c~ *.h~
diff --git a/PKGBUILD b/PKGBUILD
index b2335bc..e2d8a52 100644
--- a/PKGBUILD
+++ b/PKGBUILD
@@ -8,6 +8,7 @@ arch=('i686' 'x86_64' 'armv5tel' 'armv7l')
 url="https://github.com/esmil/lem"
 license=('GPL')
 depends=('glibc')
+optdepends=('lem-streams: for lem-repl')
 source=()
 
 build() {
diff --git a/README.markdown b/README.markdown
index fe47420..56851b9 100644
--- a/README.markdown
+++ b/README.markdown
@@ -154,7 +154,7 @@ License
 -------
 
 The Lua Event Machine is free software. It is distributed under the terms
-of the [GNU General Public License][gpl]
+of the [GNU General Public License][gpl].
 
 [gpl]: http://www.fsf.org/licensing/licenses/gpl.html
 
diff --git a/lem-repl b/lem-repl
new file mode 100755
index 0000000..c796dbe
--- /dev/null
+++ b/lem-repl
@@ -0,0 +1,31 @@
+#!/usr/bin/env lem
+--
+-- This file is part of LEM, a Lua Event Machine.
+-- Copyright 2011 Emil Renner Berthing
+--
+-- LEM is free software: you can redistribute it and/or
+-- modify it under the terms of the GNU General Public License as
+-- published by the Free Software Foundation, either version 3 of
+-- the License, or (at your option) any later version.
+--
+-- LEM is distributed in the hope that it will be useful,
+-- but WITHOUT ANY WARRANTY; without even the implied warranty of
+-- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+-- GNU General Public License for more details.
+--
+-- You should have received a copy of the GNU General Public License
+-- along with LEM.  If not, see <http://www.gnu.org/licenses/>.
+--
+
+local streams = require 'lem.streams'
+local repl    = require 'lem.repl'
+
+streams.stdout:write([[
+A Lua Event Machine 0.1  Copyright 2011 Emil Renner Berthing
+Lua 5.1.4  Copyright (C) 1994-2008 Lua.org, PUC-Rio
+libev 4.03  Copyright (C)2007,2008,2009 Marc Alexander Lehmann
+]])
+
+repl.go('stdin', streams.stdin, streams.stdout)
+
+-- vim: syntax=lua ts=2 sw=2 noet:
diff --git a/lem.c b/lem.c
index 9fd3cc5..f0af489 100644
--- a/lem.c
+++ b/lem.c
@@ -134,6 +134,17 @@ lem_forgetthread(lua_State *T)
 }
 
 void
+lem_sethandler(lua_State *T)
+{
+	/* push T to L */
+	lua_pushthread(T);
+	lua_xmove(T, L, 1);
+	/* move handler to L */
+	lua_xmove(T, L, 1);
+	lua_rawset(L, LEM_THREADTABLE);
+}
+
+void
 lem_queue(lua_State *T, int nargs)
 {
 	struct lem_runqueue_slot *slot;
@@ -220,7 +231,35 @@ runqueue_pop(EV_P_ struct ev_idle *w, int revents)
 	case LUA_ERRRUN: /* runtime error */
 		lem_debug("thread errored");
 
+		/* push T to L */
+		lua_pushthread(T);
 		lua_xmove(T, L, 1);
+
+		/* push thread_table[T] */
+		lua_pushvalue(L, -1);
+		lua_rawget(L, LEM_THREADTABLE);
+		if (lua_type(L, -1) == LUA_TFUNCTION) {
+			lua_State *S = lem_newthread();
+
+			/* move error handler to S */
+			lua_xmove(L, S, 1);
+			/* move error message to S */
+			lua_xmove(T, S, 1);
+			/* queue thread */
+			lem_debug("queueing error handler: %s",
+			          lua_tostring(S, -1));
+			lem_queue(S, 1);
+
+			/* thread_table[T] = nil */
+			lua_pushnil(L);
+			lua_rawset(L, LEM_THREADTABLE);
+			return;
+		}
+		lem_debug("no error handler");
+
+		/* move error message to L */
+		lua_xmove(T, L, 1);
+
 		rq.error = 1;
 		rq.status = EXIT_FAILURE;
 		ev_unloop(EV_A_ EVUNLOOP_ALL);
@@ -330,7 +369,7 @@ main(int argc, char *argv[])
 
 	if (rq.error) {
 		/* print error message */
-		lem_log_error("%s", lua_tostring(L, lua_gettop(L)));
+		lem_log_error("%s", lua_tostring(L, -1));
 	}
 
 	/* shutdown Lua */
diff --git a/lem.h b/lem.h
index 9dd5b41..44f6934 100644
--- a/lem.h
+++ b/lem.h
@@ -32,6 +32,7 @@ extern struct ev_loop *lem_loop;
 void *lem_xmalloc(size_t size);
 lua_State *lem_newthread();
 void lem_forgetthread(lua_State *T);
+void lem_sethandler(lua_State *T);
 void lem_queue(lua_State *T, int nargs);
 void lem_exit(int status);
 
diff --git a/repl.lua b/repl.lua
new file mode 100644
index 0000000..a3b799e
--- /dev/null
+++ b/repl.lua
@@ -0,0 +1,117 @@
+--
+-- This file is part of LEM, a Lua Event Machine.
+-- Copyright 2011 Emil Renner Berthing
+--
+-- LEM is free software: you can redistribute it and/or
+-- modify it under the terms of the GNU General Public License as
+-- published by the Free Software Foundation, either version 3 of
+-- the License, or (at your option) any later version.
+--
+-- LEM is distributed in the hope that it will be useful,
+-- but WITHOUT ANY WARRANTY; without even the implied warranty of
+-- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+-- GNU General Public License for more details.
+--
+-- You should have received a copy of the GNU General Public License
+-- along with LEM.  If not, see <http://www.gnu.org/licenses/>.
+--
+
+local utils   = require 'lem.utils'
+
+local loadstring = loadstring
+local format = string.format
+local concat = table.concat
+local tostring = tostring
+local select = select
+
+local function repl(done, name, ins, outs)
+	if not outs then outs = ins end
+
+	local getcode, onreturn, onerror
+
+	name = '=' .. name
+
+	function getcode()
+		local res, err = outs:write('> ')
+		if not res then return done(nil, err) end
+
+		local line
+		line, err = ins:read('*l')
+		if not line then return done(nil, err) end
+
+		line = line:gsub('^=', 'return ')
+
+		while true do
+			res, err = loadstring(line, name)
+			if res then break end
+
+			if not err:match("'<eof>'") then
+				return onerror(err)
+			end
+
+			res, err = outs:write('>> ')
+			if not res then return done(nil, err) end
+
+			res, err = ins:read('*l')
+			if not res then return done(nil, err) end
+
+			line = line .. res
+		end
+
+		utils.sethandler(onerror)
+		return onreturn(res())
+	end
+
+	function onreturn(...)
+		utils.sethandler()
+		local args = select('#', ...)
+		if args == 0 then return getcode() end
+
+		local rstr
+		do
+			local t, ti = { ... }, nil
+			for i = 1, args - 1 do
+				t[i] = tostring(t[i])
+			end
+			t[args] = tostring(t[args])..'\n'
+
+			rstr = concat(t, '\t')
+		end
+
+		local ok, err = outs:write(rstr)
+		if not ok then return done(nil, err) end
+
+		return getcode()
+	end
+
+	function onerror(err)
+		local ok, err = outs:write(format("ERROR: %s\n", err))
+		if not ok then return done(nil, err) end
+
+		return getcode()
+	end
+
+	return getcode()
+end
+
+return {
+	wait = function(name, ins, outs)
+		local sleeper = utils.sleeper()
+		local function done(...)
+			return sleeper:wakeup(...)
+		end
+
+		utils.spawn(repl, done, name, ins, outs)
+
+		return sleeper:sleep()
+	end,
+
+	go = function(name, ins, outs)
+		local function done()
+			return outs:write('\n')
+		end
+		return repl(done, name, ins, outs)
+	end,
+}
+
+-- vim: syntax=lua ts=2 sw=2 noet:
diff --git a/utils.c b/utils.c
index 94536f1..d2ab740 100644
--- a/utils.c
+++ b/utils.c
@@ -215,6 +215,20 @@ yield_lua(lua_State *T)
 }
 
 static int
+sethandler_lua(lua_State *T)
+{
+	if (lua_gettop(T) > 0) {
+		luaL_checktype(T, 1, LUA_TFUNCTION);
+		lua_settop(T, 1);
+	} else
+		lua_pushboolean(T, 1);
+
+	lem_sethandler(T);
+
+	return 0;
+}
+
+static int
 exit_lua(lua_State *T)
 {
 	int status = (int)luaL_checknumber(T, 1);
@@ -265,6 +279,10 @@ int luaopen_lem_utils(lua_State *L)
 	lua_pushcfunction(L, yield_lua);
 	lua_setfield(L, 2, "yield");
 
+	/* set sethandler function */
+	lua_pushcfunction(L, sethandler_lua);
+	lua_setfield(L, 2, "sethandler");
+
 	/* set exit function */
 	lua_pushcfunction(L, exit_lua);
 	lua_setfield(L, 2, "exit");