Lua init

12 files changed, 453 insertions, 144 deletions

diff --git a/make_cdrom.sh b/make_cdrom.sh
index 170d117..46cd47f 100755
--- a/make_cdrom.sh
+++ b/make_cdrom.sh
@@ -64,8 +64,11 @@ cat > cdrom/boot/grub/menu.lst <<EOF
 timeout 10
 default 0
 
-title   kogata OS
+title   kogata OS, C terminal
 kernel  /boot/kernel.bin root=io:/disk/atapi0 root_opts=l init=root:/boot/init.bin config=default
+
+title   kogata OS, Lua init
+kernel  /boot/kernel.bin root=io:/disk/atapi0 root_opts=l init=root:/boot/init.bin config=default lx_init_app=login loop_exec=false
 EOF
 
 # Generate CDROM image
diff --git a/src/lib/libc/stdio.c b/src/lib/libc/stdio.c
index 864fb34..bfa2f74 100644
--- a/src/lib/libc/stdio.c
+++ b/src/lib/libc/stdio.c
@@ -225,6 +225,10 @@ size_t fread(void *ptr, size_t size, size_t nmemb, FILE *stream) {
 }
 
 int fgetc(FILE *stream) {
+	if (stream == NULL) {
+		return EOF;
+	}
+	
 	dbg_printf("FGETC %p\n", stream);
 
 	// TODO buffering && ungetc
@@ -321,10 +325,10 @@ int setvbuf(FILE *stream, char *buf, int mode, size_t size) {
 int fflush(FILE* stream) {
 	dbg_printf("FFLUSH %p\n", stream);
 
-	if (!(stream->file_mode & FM_WRITE)) return 0;
 	if (stream == NULL || stream->fd == 0) {
 		return EOF;
 	}
+	if (!(stream->file_mode & FM_WRITE)) return 0;
 
 	if (stream->buf_mode != 0 && stream->out_buf_used > 0) {
 		size_t ret = sc_write(stream->fd, stream->pos, stream->out_buf_used, stream->out_buf);
diff --git a/src/sysapp/login/example.lua b/src/sysapp/login/example.lua
new file mode 100644
index 0000000..d099ec7
--- /dev/null
+++ b/src/sysapp/login/example.lua
@@ -0,0 +1,68 @@
+local sys = require 'lx.sys'
+local sysdef = require 'lx.sysdef'
+
+local mainloop = require 'lx.mainloop'
+local gip = require 'lx.gip'
+local draw = require 'lx.draw'
+
+
+local io = gip.new(sysdef.STD_FD_GIP)
+
+function io:damage(reg)
+  if self.features & gipdef.GIPF_DAMAGE_NOTIF ~= 0 then
+    self:send_buffer_damage(draw.region(0, 0, 256, 256))
+  end
+end
+
+function io:on_initiate(arg)
+  self.flags = arg
+
+  self:async_enumerate_modes(function(modes)
+    sys.dbg_print("Got mode list:\n")
+    for i, v in pairs(modes) do
+      sys.dbg_print(string.format("%d: %dx%d %d\n", i, v.width, v.height, v.bpp))
+    end
+
+    for i, v in pairs(modes) do
+      if v.width == 800 and v.height == 600 and v.bpp == 24 then
+        sys.dbg_print(string.format("Selecting mode %d\n", i))
+        io:send_set_mode(i)
+        return
+      end
+    end
+  end)
+end
+
+function io:on_buffer_info(arg, tok, geom)
+  self.surface = draw.surface_from_fd(sys.use_token(tok))
+  self.geom = geom
+
+  for x = 0, 255 do
+    for y = 0, 255 do
+      self.surface:put(x, y, draw.rgb(x, y, 128))
+    end
+  end
+
+  self:damage(draw.region(0, 0, 256, 256))
+end
+
+function io:async_enumerate_modes(callback)
+  local modelist = {}
+  local function gotmode(cmd, arg)
+    if arg == nil then
+      callback(modelist)
+    else
+      modelist[#modelist + 1] = arg
+      io.on_reply[io:send_query_mode(#modelist)] = gotmode
+    end
+  end
+  io.on_reply[io:send_query_mode(#modelist)] = gotmode
+end
+
+mainloop.add(io)
+
+io:send_reset()
+mainloop.run()
+
+
+
diff --git a/src/sysapp/login/main.lua b/src/sysapp/login/main.lua
index d099ec7..dec8b82 100644
--- a/src/sysapp/login/main.lua
+++ b/src/sysapp/login/main.lua
@@ -1,68 +1,20 @@
 local sys = require 'lx.sys'
-local sysdef = require 'lx.sysdef'
+local sysdef= require 'lx.sysdef'
+local ioctl = require 'lx.ioctl'
 
-local mainloop = require 'lx.mainloop'
-local gip = require 'lx.gip'
-local draw = require 'lx.draw'
+print("Hello, world!")
 
+local vesa_fd = sys.open("io:/display/vesa", sysdef.FM_IOCTL | sysdef.FM_READ | sysdef.FM_WRITE | sysdef.FM_MMAP)
+print("vesa_fd = " .. vesa_fd)
 
-local io = gip.new(sysdef.STD_FD_GIP)
+local vesa_info = ioctl.fb_get_info(vesa_fd)
+print("vesa_info = ", vesa_info)
 
-function io:damage(reg)
-  if self.features & gipdef.GIPF_DAMAGE_NOTIF ~= 0 then
-    self:send_buffer_damage(draw.region(0, 0, 256, 256))
-  end
+local i = 1
+while true do
+	print(i)
+	i = i + 1
+	sys.usleep(1000000)
 end
 
-function io:on_initiate(arg)
-  self.flags = arg
-
-  self:async_enumerate_modes(function(modes)
-    sys.dbg_print("Got mode list:\n")
-    for i, v in pairs(modes) do
-      sys.dbg_print(string.format("%d: %dx%d %d\n", i, v.width, v.height, v.bpp))
-    end
-
-    for i, v in pairs(modes) do
-      if v.width == 800 and v.height == 600 and v.bpp == 24 then
-        sys.dbg_print(string.format("Selecting mode %d\n", i))
-        io:send_set_mode(i)
-        return
-      end
-    end
-  end)
-end
-
-function io:on_buffer_info(arg, tok, geom)
-  self.surface = draw.surface_from_fd(sys.use_token(tok))
-  self.geom = geom
-
-  for x = 0, 255 do
-    for y = 0, 255 do
-      self.surface:put(x, y, draw.rgb(x, y, 128))
-    end
-  end
-
-  self:damage(draw.region(0, 0, 256, 256))
-end
-
-function io:async_enumerate_modes(callback)
-  local modelist = {}
-  local function gotmode(cmd, arg)
-    if arg == nil then
-      callback(modelist)
-    else
-      modelist[#modelist + 1] = arg
-      io.on_reply[io:send_query_mode(#modelist)] = gotmode
-    end
-  end
-  io.on_reply[io:send_query_mode(#modelist)] = gotmode
-end
-
-mainloop.add(io)
-
-io:send_reset()
-mainloop.run()
-
-
-
+os.exit()
diff --git a/src/sysbin/init/main.c b/src/sysbin/init/main.c
index ce09f37..e923ab3 100644
--- a/src/sysbin/init/main.c
+++ b/src/sysbin/init/main.c
@@ -9,8 +9,8 @@
 
 #include <kogata/btree.h>
 
-pid_t giosrv_pid = 0, login_pid = 0;
-fd_pair_t root_gip_chan;
+bool loop_exec = true;
+pid_t giosrv_pid = 0, login_pid = 0, lx_init_pid = 0;
 
 void _parse_cmdline_iter(void* a, void* b) {
 	dbg_printf("  '%s'  ->  '%s'\n", a, b);
@@ -90,7 +90,7 @@ void setup_sys() {
 	if (!ok) PANIC("[init] Could not bind root:/sys to sys:/");
 }
 
-void launch_giosrv() {
+void launch_giosrv(fd_pair_t *root_gip_chan) {
 	if (giosrv_pid != 0) return;
 
 	giosrv_pid = sc_new_proc();
@@ -111,7 +111,7 @@ void launch_giosrv() {
 	ok = sc_bind_fs(giosrv_pid, "config", "config");
 	if (!ok) PANIC("[init] Could not bind config:/ to giosrv");
 
-	ok = sc_bind_fd(giosrv_pid, STD_FD_GIOSRV, root_gip_chan.a);
+	ok = sc_bind_fd(giosrv_pid, STD_FD_GIOSRV, root_gip_chan->a);
 	if (!ok) PANIC("[init] Could not bind root GIP channel FD to giosrv");
 
 	ok = sc_proc_exec(giosrv_pid, "sys:/bin/giosrv.bin");
@@ -120,7 +120,7 @@ void launch_giosrv() {
 	dbg_printf("[init] giosrv started.\n");
 }
 
-void launch_login() {
+void launch_login(fd_pair_t *root_gip_chan) {
 	if (login_pid != 0) return;
 
 	login_pid = sc_new_proc();
@@ -141,7 +141,7 @@ void launch_login() {
 	ok = sc_bind_fs(login_pid, "config", "config");
 	if (!ok) PANIC("[init] Could not bind config:/ to login");
 
-	ok = sc_bind_fd(login_pid, STD_FD_GIP, root_gip_chan.b);
+	ok = sc_bind_fd(login_pid, STD_FD_GIP, root_gip_chan->b);
 	if (!ok) PANIC("[init] Could not bind root GIP channel FD to login");
 
 	ok = sc_proc_exec(login_pid, "sys:/bin/login.bin");
@@ -150,30 +150,99 @@ void launch_login() {
 	dbg_printf("[init] login started.\n");
 }
 
-int main(int argc, char **argv) {
-	dbg_print("[init] Starting up!\n");
+void launch_lx_init(const char* lx_init_app, fd_pair_t *io_chan) {
+	if (lx_init_pid != 0) return;
 
-	// Read kernel cmdline
-	btree_t *cmdline = read_cmdline();
-	if (cmdline == 0) PANIC("[init] Could not parse cmdline");
+	lx_init_pid = sc_new_proc();
+	if (lx_init_pid == 0) {
+		PANIC("[init] Could not create process for lx_init");
+	}
 
-	// setup config:
-	if (btree_find(cmdline, "config") == 0) {
-		PANIC("[init] No config=xxx option specified on command line");
-	} else {
-		char* config = (char*)btree_find(cmdline, "config");
-		dbg_printf("[init] Loading system configuration: %s\n", config);
-		ASSERT(strlen(config) < 30);
+	dbg_printf("[init] Setting up lx_init, pid: %d\n", lx_init_pid);
 
-		char buf[50];
-		snprintf(buf, 50, "/config/%s", config);
-		bool ok = sc_fs_subfs("config", "root", buf, FM_READ | FM_WRITE | FM_MMAP | FM_READDIR);
-		if (!ok) PANIC("[init] Could not setup config:");
+	bool ok;
+
+	ok = sc_bind_fs(lx_init_pid, "io", "io");
+	if (!ok) PANIC("[init] Could not bind io:/ to lx_init");
+
+	ok = sc_bind_fs(lx_init_pid, "root", "root");
+	if (!ok) PANIC("[init] Could not bind root:/ to lx_init");
+
+	ok = sc_bind_fs(lx_init_pid, "sys", "sys");
+	if (!ok) PANIC("[init] Could not bind sys:/ to lx_init");
+
+	ok = sc_bind_fs(lx_init_pid, "config", "config");
+	if (!ok) PANIC("[init] Could not bind config:/ to lx_init");
+
+	char app_path[256];
+	snprintf(app_path, 256, "/app/%s", lx_init_app);
+
+	ok = sc_bind_subfs(lx_init_pid, "app", "sys", app_path, FM_ALL_MODES);
+	if (!ok) PANIC("[init] Could not bind app:/ to lx_init");
+
+	ok = sc_bind_fd(lx_init_pid, STD_FD_STDOUT, io_chan->b);
+	if (!ok) PANIC("[init] Could not bind stdout channel to lx_init");
+
+	ok = sc_bind_fd(lx_init_pid, STD_FD_STDERR, io_chan->b);
+	if (!ok) PANIC("[init] Could not bind stderr channel to lx_init");
+
+	ok = sc_proc_exec(lx_init_pid, "sys:/bin/lx.bin");
+	if (!ok) PANIC("[init] Could not run lx.bin");
+
+	dbg_printf("[init] lx_init started\n");
+}
+
+void dump_all(fd_t fd) {
+	char buf[256];
+	while(true){
+		int n = sc_read(fd, 0, 255, buf);
+		if (n > 0) {
+			buf[n] = 0;
+			sc_dbg_print(buf);
+		} else {
+			break;
+		}
 	}
+}
 
-	// Setup sys:
-	setup_sys();
+int run_lua(const char* lx_init_app) {
+	// Setup a channel for stdout/stderr printing
+	fd_pair_t io_chan;
+	io_chan = sc_make_channel(false);
+	if (io_chan.a == 0 || io_chan.b == 0) {
+		PANIC("[init] Could not create Lua emergency I/O channel.");
+	}
+
+	launch_lx_init(lx_init_app, &io_chan);
+
+	while(true) {
+		dump_all(io_chan.a);
+
+		proc_status_t s;
+		sc_proc_wait(0, false, &s);
+		if (s.pid != 0) {
+			if (s.pid == lx_init_pid) {
+				if (!loop_exec) {
+					dump_all(io_chan.a);
+					PANIC("[init] lx_init died!\n");
+				}
+
+				lx_init_pid = 0;
+
+				dbg_printf("[init] lx_init_app died, restarting.\n");
+				launch_lx_init(lx_init_app, &io_chan);
+			} else {
+				ASSERT(false);
+			}
+		}
+
+		sc_usleep(100000);
+	}
+}
 
+int run_no_lua() {
+	fd_pair_t root_gip_chan;
+	
 	// Setup GIP channel for communication between giosrv and login
 	root_gip_chan = sc_make_channel(false);
 	if (root_gip_chan.a == 0 || root_gip_chan.b == 0) {
@@ -181,8 +250,8 @@ int main(int argc, char **argv) {
 	}
 
 	// Launch giosrv && login
-	launch_giosrv();
-	launch_login();
+	launch_giosrv(&root_gip_chan);
+	launch_login(&root_gip_chan);
 
 	// Make sure no one dies
 	while(true) {
@@ -190,21 +259,60 @@ int main(int argc, char **argv) {
 		sc_proc_wait(0, false, &s);
 		if (s.pid != 0) {
 			if (s.pid == giosrv_pid) {
+				if (!loop_exec) PANIC("[init] giosrv died!\n");
+
 				giosrv_pid = 0;
 
 				dbg_printf("[init] giosrv died, restarting.\n");
-				launch_giosrv();
+				launch_giosrv(&root_gip_chan);
 			} else if (s.pid == login_pid) {
+				if (!loop_exec) PANIC("[init] login died!\n");
+
 				login_pid = 0;
 
 				dbg_printf("[init] login died, restarting.\n");
-				launch_login();
+				launch_login(&root_gip_chan);
 			} else {
 				ASSERT(false);
 			}
 		}
 		sc_usleep(1000000);
 	}
+}
+
+int main(int argc, char **argv) {
+	dbg_print("[init] Starting up!\n");
+
+	// Read kernel cmdline
+	btree_t *cmdline = read_cmdline();
+	if (cmdline == 0) PANIC("[init] Could not parse cmdline");
+
+	// setup config:
+	if (btree_find(cmdline, "config") == 0) {
+		PANIC("[init] No config=xxx option specified on command line");
+	} else {
+		char* config = (char*)btree_find(cmdline, "config");
+		dbg_printf("[init] Loading system configuration: %s\n", config);
+		ASSERT(strlen(config) < 30);
+
+		char buf[50];
+		snprintf(buf, 50, "/config/%s", config);
+		bool ok = sc_fs_subfs("config", "root", buf, FM_READ | FM_WRITE | FM_MMAP | FM_READDIR);
+		if (!ok) PANIC("[init] Could not setup config:");
+	}
+
+	// Setup sys:
+	setup_sys();
+
+	if (btree_find(cmdline, "loop_exec") &&
+		strcmp(btree_find(cmdline, "loop_exec"), "true"))
+		loop_exec = false;
+
+	if (btree_find(cmdline, "lx_init_app")) {
+		run_lua(btree_find(cmdline, "lx_init_app"));
+	} else {
+		run_no_lua();
+	}
 
 	return 0;
 }
diff --git a/src/sysbin/lx/lxinit.c b/src/sysbin/lx/lxinit.c
index c185b45..b727ccd 100644
--- a/src/sysbin/lx/lxinit.c
+++ b/src/sysbin/lx/lxinit.c
@@ -35,6 +35,7 @@
 static const luaL_Reg loadedlibs[] = {
   {LX_SYSLIBNAME, lx_open_sys},
   {LX_MSGLIBNAME, lx_open_msg},
+  {LX_IOCTLLIBNAME, lx_open_ioctl},
   {NULL, NULL}
 };
 
diff --git a/src/sysbin/lx/lxioctllib.c b/src/sysbin/lx/lxioctllib.c
new file mode 100644
index 0000000..4b9be91
--- /dev/null
+++ b/src/sysbin/lx/lxioctllib.c
@@ -0,0 +1,62 @@
+/*
+** Lua eXtended ioctl library
+*/
+
+#define lxioctllib_c
+#define LUA_LIB
+
+#include <lua/lprefix.h>
+
+
+#include <errno.h>
+#include <locale.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+
+#include <lua/lua.h>
+
+#include <lua/lauxlib.h>
+#include <lua/lualib.h>
+
+#include <kogata/syscall.h>
+#include <kogata/gip.h>
+
+#include "lxlib.h"
+
+
+static int ioctl_fb_get_info(lua_State *L) {
+  int fd = luaL_checkinteger(L, 1);
+
+  fb_info_t mode;
+  int r = sc_ioctl(fd, IOCTL_FB_GET_INFO, &mode);
+  if (r == 1) {
+    lua_createtable(L, 0, 5);
+    setintfield(L, "width", mode.width);
+    setintfield(L, "height", mode.height);
+    setintfield(L, "pitch", mode.pitch);
+    setintfield(L, "bpp", mode.bpp);
+    setintfield(L, "memory_model", mode.memory_model);
+  } else {
+    lua_pushnil(L);
+  }
+
+	return 1;
+}
+
+
+/* }====================================================== */
+
+static const luaL_Reg ioctllib[] = {
+  {"fb_get_info",		ioctl_fb_get_info},
+  {NULL, NULL}
+};
+
+
+LUAMOD_API int lx_open_ioctl (lua_State *L) {
+  luaL_newlib(L, ioctllib);
+  return 1;
+}
+
+
+/* vim: set sts=2 ts=2 sw=2 tw=0 et :*/
diff --git a/src/sysbin/lx/lxlib.c b/src/sysbin/lx/lxlib.c
new file mode 100644
index 0000000..9f6843b
--- /dev/null
+++ b/src/sysbin/lx/lxlib.c
@@ -0,0 +1,41 @@
+/*
+** Lua eXtended library helpers
+*/
+
+#define lxsyslib_c
+#define LUA_LIB
+
+#include <lua/lprefix.h>
+
+
+#include <errno.h>
+#include <locale.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+
+#include <lua/lua.h>
+
+#include <lua/lauxlib.h>
+#include <lua/lualib.h>
+
+#include "lxlib.h"
+
+
+bool lx_checkboolean(lua_State *L, int arg) {
+  if (!lua_isboolean(L, arg)) {
+    luaL_argerror(L, arg, "expected boolean");
+  }
+  return lua_toboolean(L, arg);
+}
+
+
+void setintfield (lua_State *L, const char *key, int value) {
+  lua_pushinteger(L, value);
+  lua_setfield(L, -2, key);
+}
+
+void setstrfield (lua_State *L, const char *key, const char* value) {
+  lua_pushstring(L, value);
+  lua_setfield(L, -2, key);
+}
diff --git a/src/sysbin/lx/lxlib.h b/src/sysbin/lx/lxlib.h
index 199c78d..260db97 100644
--- a/src/sysbin/lx/lxlib.h
+++ b/src/sysbin/lx/lxlib.h
@@ -6,12 +6,18 @@
 #include <lua/lua.h>
 
 
-#define LX_SYSLIBNAME "lx.sys"
-LUAMOD_API int (lx_open_sys) (lua_State *L);
+// Helper for libraries
+bool lx_checkboolean(lua_State *L, int arg);
+void setintfield (lua_State *L, const char *key, int value);
+void setstrfield (lua_State *L, const char *key, const char* value);
+
 
 #define LX_SYSLIBNAME "lx.sys"
 LUAMOD_API int (lx_open_sys) (lua_State *L);
 
+#define LX_IOCTLLIBNAME "lx.ioctl"
+LUAMOD_API int (lx_open_ioctl) (lua_State *L);
+
 #define LX_MSGLIBNAME "lx.msg"
 LUAMOD_API int (luaopen_cmsgpack) (lua_State *L);
 #define lx_open_msg luaopen_cmsgpack
diff --git a/src/sysbin/lx/lxsyslib.c b/src/sysbin/lx/lxsyslib.c
index 52c6978..72c9882 100644
--- a/src/sysbin/lx/lxsyslib.c
+++ b/src/sysbin/lx/lxsyslib.c
@@ -22,25 +22,6 @@
 #include "lxlib.h"
 
 
-bool lx_checkboolean(lua_State *L, int arg) {
-  if (!lua_isboolean(L, arg)) {
-    luaL_argerror(L, arg, "expected boolean");
-  }
-  return lua_toboolean(L, arg);
-}
-
-
-static void setintfield (lua_State *L, const char *key, int value) {
-  lua_pushinteger(L, value);
-  lua_setfield(L, -2, key);
-}
-
-static void setstrfield (lua_State *L, const char *key, const char* value) {
-  lua_pushstring(L, value);
-  lua_setfield(L, -2, key);
-}
-
-
 static int sys_dbg_print(lua_State *L) {
   const char *str = luaL_checkstring(L, 1);
   sc_dbg_print(str);
@@ -68,6 +49,7 @@ static int sys_usleep(lua_State *L) {
     Missing syscalls :
     - sys_new_thread, exit_thread -> into specific threading library
     - mmap, mmap_file, mchmap, munmap -> into specific memory-related library ??
+    - ioctl, fctl -> into ioctl library
 */
 
 static int sys_create(lua_State *L) {
@@ -180,25 +162,10 @@ static int sys_stat_open(lua_State *L) {
   return 1;
 }
 
-static int sys_ioctl(lua_State *L) {
-  // TODO
-  return 0;
-}
-
-static int sys_fctl(lua_State *L) {
-  // TODO
-  return 0;
-}
-
 static int sys_select(lua_State *L) {
   luaL_checktype(L, 1, LUA_TTABLE);
   int nfds = luaL_len(L, 1);
-  int timeout;
-  if (lua_isinteger(L, 2)) {
-    timeout = luaL_checkinteger(L, 2);
-  } else {
-    timeout = 0;
-  }
+  int timeout = luaL_checkinteger(L, 2);
 
   sel_fd_t *fds = (sel_fd_t*)malloc(nfds*sizeof(sel_fd_t));
   if (fds == NULL)
@@ -398,6 +365,7 @@ static int sys_proc_wait(lua_State *L) {
   return 1;
 }
 
+/* }====================================================== */
 
 static const luaL_Reg syslib[] = {
   {"dbg_print", sys_dbg_print},
@@ -414,8 +382,6 @@ static const luaL_Reg syslib[] = {
   {"write",     sys_write},
   {"readdir",   sys_readdir},
   {"stat_open", sys_stat_open},
-  {"ioctl",     sys_ioctl},
-  {"fctl",      sys_fctl},
   {"select",    sys_select},
   {"make_channel",sys_make_channel},
   {"make_shm",  sys_make_shm},
@@ -438,9 +404,6 @@ static const luaL_Reg syslib[] = {
   {NULL, NULL}
 };
 
-/* }====================================================== */
-
-
 
 LUAMOD_API int lx_open_sys (lua_State *L) {
   luaL_newlib(L, syslib);
diff --git a/src/sysbin/lx/main.c b/src/sysbin/lx/main.c
index b7e08d9..573e1bb 100644
--- a/src/sysbin/lx/main.c
+++ b/src/sysbin/lx/main.c
@@ -346,12 +346,26 @@ int handle_luainit (lua_State *L) {
 }
 
 
-/*
-** Main body of stand-alone interpreter (to be called in protected mode).
-** Reads the options and handles them all.
-*/
+bool find_lua_main(lua_State *L) {
+  lua_getglobal(L, "package");
+  if (lua_getfield(L, -1, "searchers") != LUA_TTABLE)
+    luaL_error(L, "'package.searchers' must be a table");
+  lua_remove(L, -2);
+  for (int i = 1; ; i++) {
+    if (lua_rawgeti(L, -1, i) == LUA_TNIL) {  /* no more searchers? */
+      lua_pop(L, 2);  // pop nil & searchers table
+      return false;
+    }
+    lua_pushstring(L, "main");
+    lua_call(L, 1, 2);  /* call it */
+    if (lua_isfunction(L, -2))  /* did it find a loader? */
+      return true;  /* module loader found */
+    else
+      lua_pop(L, 2);  /* remove both returns */
+  }
+}
+
 int pmain (lua_State *L) {
-  int status;
   luaL_checkversion(L);  /* check that interpreter has correct version */
     
   print_version();
@@ -362,18 +376,20 @@ int pmain (lua_State *L) {
   if (handle_luainit(L) != LUA_OK)  /* run LUA_INIT */
     return 0;  /* error running LUA_INIT */
 
-  lua_getglobal(L, "require");
-  lua_pushstring(L, "main");
-  status = docall(L, 1, 1);  /* call 'require("main")' */
-  if (status != LUA_OK) {
+  if (find_lua_main(L)) {
+    // call loader
+    lua_pushstring(L, "main");
+    lua_insert(L, -2);
+    lua_call(L, 2, 1);
+  } else {
     // no main, launch a REPL
     if (lua_stdin_is_tty()) {  /* running in interactive mode? */
       doREPL(L);  /* do read-eval-print loop */
     } else {
-       dofile(L, NULL);  /* executes stdin as a file */
+      dofile(L, NULL);  /* executes stdin as a file */
     }
+    lua_pushboolean(L, 1);  /* signal no errors */
   }
-  lua_pushboolean(L, 1);  /* signal no errors */
   return 1;
 }
 
diff --git a/src/syslua/lx/mainloop.lua b/src/syslua/lx/mainloop.lua
new file mode 100644
index 0000000..c2ae88d
--- /dev/null
+++ b/src/syslua/lx/mainloop.lua
@@ -0,0 +1,85 @@
+local sys = require 'lx.sys'
+local sysdef = require 'lx.sysdef'
+
+local mainloop = {}
+
+local fds = {}
+local mainloop_must_exit = false
+local mainloop_fds_change = false
+
+function new_fd(fd, error_cb)
+	local fd = {
+		fd = fd,
+		error_cb = error_cb,
+		rd_expect = {},
+		wr_buf = "",
+	}
+	function fd:write(str)
+		-- TODO: try write immediately when possible
+		self.wr_buf = self.wr_buf .. str
+	end
+	function fd:expect(len, cb)
+		table.insert(self.rd_expect, {len, "", cb})
+	end
+end
+
+function mainloop.add_fd(fd, error_cb)
+	local fd = new_fd(fd, error_cb)
+	table.insert(fds, fd)
+	mainloop_fds_change = true
+	return fd
+end
+
+function mainloop.run()
+	mainloop_must_exit = false
+	sel_fds = {}
+	while not mainloop_must_exit do
+		local deadlock = true
+		for i, fd in pairs(fds) do
+			if mainloop_fds_change then
+				sel_fds[i] = {fd.fd}
+			end
+			local flags = sysdef.SEL_ERROR
+			if fd.rd_expect[1] then
+				flags = flags | sysdef.SEL_READ
+				deadlock = false
+			end
+			if #fd.wr_buf > 0 then
+				flags = flags | sysdef.SEL_WRITE
+				deadlock = false
+			end
+			sel_fds[i][2] = flags
+		end
+		mainloop_fds_change = false
+		assert(not deadlock, "Mainloop does nothing!")
+
+		local res = sys.select(sel_fds, -1)
+		assert(res, "select() call failed")
+		for i, fd = pairs(fds) do
+			local flags = sel_fds[i][3]
+			if flags & sysdef.SEL_ERROR ~= 0 then
+				fd.error_cb(fd)
+			else
+				if flags & sysdef.SEL_READ ~= 0 then
+					local reader = fd.rd_expect[1]
+					local tmp = sys.read(fd.fd, 0, reader[1] - #reader[2])
+					reader[2] = reader[2] .. tmp
+					if #reader[2] == reader[1] then
+						reader[3](reader[2])
+						table.remove(fd.rd_expect, 1)
+					end
+				end
+				if flags & sysdef.SEL_WRITE ~= 0 then
+					local r = sys.write(fd.fd, 0, fd.wr_buf)
+					fd.wr_buf = fd.wr_buf:sub(r+1)
+				end
+			end
+		end
+	end
+end
+
+function mainloop.exit()
+	mainloop_must_exit = true
+end
+
+return mainloop