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authormbalmer <mbalmer@NetBSD.org>2013-10-16 19:44:57 +0000
committermbalmer <mbalmer@NetBSD.org>2013-10-16 19:44:57 +0000
commite0fe45ce9c35c204a7c19d5a5291ca64b47b2452 (patch)
treee871dc37f16f51aff76180bb26119b0ced6630a4 /sys/modules/lua/lua.c
parenta1bd524499a4e93e3f6f934dc1e6f644595e0a89 (diff)
welcome lua(4), a devide driver that can create and control Lua states inside the kernel
Diffstat (limited to 'sys/modules/lua/lua.c')
-rw-r--r--sys/modules/lua/lua.c862
1 files changed, 862 insertions, 0 deletions
diff --git a/sys/modules/lua/lua.c b/sys/modules/lua/lua.c
new file mode 100644
index 00000000000..7fd0001a186
--- /dev/null
+++ b/sys/modules/lua/lua.c
@@ -0,0 +1,862 @@
+/* $NetBSD */
+
+/*
+ * Copyright (c) 2011 by Marc Balmer <mbalmer@NetBSD.org>.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. The name of the Author may not be used to endorse or promote products
+ * derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+/* Lua device driver */
+
+#include <sys/param.h>
+#include <sys/fcntl.h>
+#include <sys/conf.h>
+#include <sys/condvar.h>
+#include <sys/device.h>
+#include <sys/ioctl.h>
+#include <sys/lock.h>
+#include <sys/lua.h>
+#include <sys/malloc.h>
+#include <sys/module.h>
+#include <sys/mutex.h>
+#include <sys/namei.h>
+#include <sys/queue.h>
+#include <sys/sysctl.h>
+#include <sys/vnode.h>
+
+#include <lauxlib.h>
+
+#include "luavar.h"
+
+struct lua_softc {
+ device_t sc_dev;
+
+ kmutex_t sc_lock;
+ kcondvar_t sc_inuse_cv;
+ bool sc_inuse;
+
+ /* Locking access to state queues */
+ kmutex_t sc_state_lock;
+ kcondvar_t sc_state_cv;
+ bool sc_state;
+
+ struct sysctllog *sc_log;
+};
+
+static device_t sc_self;
+static bool lua_autoload_on = true;
+static bool lua_require_on = true;
+static bool lua_bytecode_on = false;
+static int lua_verbose;
+static int lua_max_instr;
+
+static LIST_HEAD(, lua_state) lua_states;
+static LIST_HEAD(, lua_module) lua_modules;
+
+static int lua_match(device_t, cfdata_t, void *);
+static void lua_attach(device_t, device_t, void *);
+static int lua_detach(device_t, int);
+static klua_State *klua_find(const char *);
+static const char *lua_reader(lua_State *, void *, size_t *);
+static void lua_maxcount(lua_State *, lua_Debug *);
+
+static int lua_require(lua_State *);
+
+CFATTACH_DECL_NEW(lua, sizeof(struct lua_softc),
+ lua_match, lua_attach, lua_detach, NULL);
+
+dev_type_open(luaopen);
+dev_type_close(luaclose);
+dev_type_ioctl(luaioctl);
+
+const struct cdevsw lua_cdevsw = {
+ luaopen, luaclose, noread, nowrite, luaioctl, nostop, notty,
+ nopoll, nommap, nokqfilter, D_OTHER | D_MPSAFE
+};
+
+struct lua_loadstate {
+ struct vnode *vp;
+ size_t size;
+ off_t off;
+};
+
+extern struct cfdriver lua_cd;
+
+static int
+lua_match(device_t parent, cfdata_t match, void *aux)
+{
+ return 1;
+}
+
+static void
+lua_attach(device_t parent, device_t self, void *aux)
+{
+ struct lua_softc *sc;
+ const struct sysctlnode *node;
+
+ if (sc_self)
+ return;
+
+ sc = device_private(self);
+ sc->sc_dev = self;
+ sc_self = self;
+
+ mutex_init(&sc->sc_lock, MUTEX_DEFAULT, IPL_VM);
+ cv_init(&sc->sc_inuse_cv, "luactl");
+
+ mutex_init(&sc->sc_state_lock, MUTEX_DEFAULT, IPL_VM);
+ cv_init(&sc->sc_state_cv, "luastate");
+
+ pmf_device_register(self, NULL, NULL);
+
+ /* Sysctl to provide some control over behaviour */
+ sysctl_createv(NULL, 0, NULL, NULL,
+ CTLFLAG_PERMANENT,
+ CTLTYPE_NODE, "kern", NULL,
+ NULL, 0, NULL, 0,
+ CTL_KERN, CTL_EOL);
+ sysctl_createv(&sc->sc_log, 0, NULL, &node,
+ CTLFLAG_OWNDESC,
+ CTLTYPE_NODE, "lua",
+ SYSCTL_DESCR("Lua options"),
+ NULL, 0, NULL, 0,
+ CTL_KERN, CTL_CREATE, CTL_EOL);
+
+ if (node == NULL) {
+ printf(": can't create sysctl node\n");
+ return;
+ }
+
+ /*
+ * XXX Some of the sysctl values must not be changed after the
+ * securelevel has been raised.
+ */
+ sysctl_createv(&sc->sc_log, 0, &node, NULL,
+ CTLFLAG_READWRITE | CTLFLAG_OWNDESC,
+ CTLTYPE_BOOL, "require",
+ SYSCTL_DESCR("Enable the require command"),
+ NULL, 0, &lua_require_on, 0,
+ CTL_CREATE, CTL_EOL);
+
+ sysctl_createv(&sc->sc_log, 0, &node, NULL,
+ CTLFLAG_READWRITE | CTLFLAG_OWNDESC,
+ CTLTYPE_BOOL, "autoload",
+ SYSCTL_DESCR("Enable automatic load of modules"),
+ NULL, 0, &lua_autoload_on, 0,
+ CTL_CREATE, CTL_EOL);
+
+ sysctl_createv(&sc->sc_log, 0, &node, NULL,
+ CTLFLAG_READWRITE | CTLFLAG_OWNDESC,
+ CTLTYPE_BOOL, "bytecode",
+ SYSCTL_DESCR("Enable loading of bytecode"),
+ NULL, 0, &lua_bytecode_on, 0,
+ CTL_CREATE, CTL_EOL);
+
+ sysctl_createv(&sc->sc_log, 0, &node, NULL,
+ CTLFLAG_READWRITE | CTLFLAG_OWNDESC,
+ CTLTYPE_INT, "verbose",
+ SYSCTL_DESCR("Enable verbose output"),
+ NULL, 0, &lua_verbose, 0,
+ CTL_CREATE, CTL_EOL);
+
+ sysctl_createv(&sc->sc_log, 0, &node, NULL,
+ CTLFLAG_READWRITE | CTLFLAG_OWNDESC,
+ CTLTYPE_INT, "maxcount",
+ SYSCTL_DESCR("Limit maximum instruction count"),
+ NULL, 0, &lua_max_instr, 0,
+ CTL_CREATE, CTL_EOL);
+
+ aprint_normal_dev(self, "%s %s\n", LUA_RELEASE, LUA_COPYRIGHT);
+}
+
+static int
+lua_detach(device_t self, int flags)
+{
+ struct lua_softc *sc;
+ struct lua_state *s;
+
+ sc = device_private(self);
+ pmf_device_deregister(self);
+
+ if (sc->sc_log != NULL) {
+ sysctl_teardown(&sc->sc_log);
+ sc->sc_log = NULL;
+ }
+
+ /* Traverse the list of states and close them */
+ while ((s = LIST_FIRST(&lua_states)) != NULL) {
+ LIST_REMOVE(s, lua_next);
+ klua_close(s->K);
+ if (lua_verbose)
+ device_printf(self, "state %s destroyed\n",
+ s->lua_name);
+ free(s, NULL);
+ }
+ mutex_destroy(&sc->sc_lock);
+ cv_destroy(&sc->sc_inuse_cv);
+ mutex_destroy(&sc->sc_state_lock);
+ cv_destroy(&sc->sc_state_cv);
+ sc_self = NULL;
+ return 0;
+}
+
+int
+luaopen(dev_t dev, int flag, int mode, struct lwp *l)
+{
+ struct lua_softc *sc;
+ int error;
+
+ if (minor(dev) > 0)
+ return ENXIO;
+
+ sc = device_lookup_private(&lua_cd, minor(dev));
+ if (sc == NULL)
+ return ENXIO;
+
+ mutex_enter(&sc->sc_lock);
+ while (sc->sc_inuse == true) {
+ error = cv_wait_sig(&sc->sc_inuse_cv, &sc->sc_lock);
+ if (error)
+ break;
+ }
+ if (!error)
+ sc->sc_inuse = true;
+ mutex_exit(&sc->sc_lock);
+
+ if (error)
+ return error;
+ return 0;
+}
+
+int
+luaclose(dev_t dev, int flag, int mode, struct lwp *l)
+{
+ struct lua_softc *sc;
+
+ if (minor(dev) > 0)
+ return ENXIO;
+ sc = device_lookup_private(&lua_cd, minor(dev));
+ mutex_enter(&sc->sc_lock);
+ sc->sc_inuse = false;
+ cv_signal(&sc->sc_inuse_cv);
+ mutex_exit(&sc->sc_lock);
+ return 0;
+}
+
+int
+luaioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l)
+{
+ struct lua_softc *sc;
+ struct lua_info *info;
+ struct lua_create *create;
+ struct lua_require *require;
+ struct lua_load *load;
+ struct lua_state *s;
+ struct lua_module *m;
+ kauth_cred_t cred;
+ struct nameidata nd;
+ struct pathbuf *pb;
+ struct vattr va;
+ struct lua_loadstate ls;
+ int error, n;
+ klua_State *K;
+
+ sc = device_lookup_private(&lua_cd, minor(dev));
+ if (!device_is_active(sc->sc_dev))
+ return EBUSY;
+
+ switch (cmd) {
+ case LUAINFO:
+ info = data;
+ if (info->states == NULL) {
+ info->num_states = 0;
+ LIST_FOREACH(s, &lua_states, lua_next)
+ info->num_states++;
+ } else {
+ n = 0;
+ LIST_FOREACH(s, &lua_states, lua_next) {
+ if (n > info->num_states)
+ break;
+ copyoutstr(s->lua_name, info->states[n].name,
+ MAX_LUA_NAME, NULL);
+ copyoutstr(s->lua_desc, info->states[n].desc,
+ MAX_LUA_DESC, NULL);
+ info->states[n].user = s->K->ks_user;
+ n++;
+ }
+ info->num_states = n;
+ }
+ break;
+ case LUACREATE:
+ create = data;
+
+ if (*create->name == '_') {
+ if (lua_verbose)
+ device_printf(sc->sc_dev, "names of user "
+ "created states must not begin with '_'");
+ return ENXIO;
+ }
+ LIST_FOREACH(s, &lua_states, lua_next)
+ if (!strcmp(s->lua_name, create->name)) {
+ if (lua_verbose)
+ device_printf(sc->sc_dev,
+ "state %s exists\n", create->name);
+ return EBUSY;
+ }
+
+ K = klua_newstate(lua_alloc, NULL, create->name,
+ create->desc);
+ K->ks_user = true;
+
+ if (K == NULL)
+ return ENOMEM;
+ if (lua_verbose)
+ device_printf(sc->sc_dev, "state %s created\n",
+ create->name);
+ break;
+ case LUADESTROY:
+ create = data;
+
+ K = klua_find(create->name);
+
+ if (K != NULL && (K->ks_user == true)) {
+ klua_close(K);
+ return 0;
+ }
+ return EBUSY;
+ case LUAREQUIRE: /* 'require' a module in a State */
+ require = data;
+ LIST_FOREACH(s, &lua_states, lua_next)
+ if (!strcmp(s->lua_name, require->state))
+ LIST_FOREACH(m, &lua_modules, mod_next)
+ if (!strcmp(m->mod_name,
+ require->module)) {
+ if (lua_verbose)
+ device_printf(
+ sc->sc_dev,
+ "requiring module "
+ "%s to state %s\n",
+ m->mod_name,
+ s->lua_name);
+ m->open(s->K->L);
+ m->refcount++;
+ LIST_INSERT_HEAD(
+ &s->lua_modules, m,
+ mod_next);
+ return 0;
+ }
+ return ENXIO;
+ case LUALOAD:
+ load = data;
+ if (strrchr(load->path, '/') == NULL)
+ return ENXIO;
+
+ LIST_FOREACH(s, &lua_states, lua_next)
+ if (!strcmp(s->lua_name, load->state)) {
+ if (lua_verbose)
+ device_printf(sc->sc_dev,
+ "loading %s into state %s\n",
+ load->path, s->lua_name);
+ cred = kauth_cred_get();
+ pb = pathbuf_create(load->path);
+ if (pb == NULL)
+ return ENOMEM;
+ NDINIT(&nd, LOOKUP, FOLLOW | NOCHROOT, pb);
+ pathbuf_destroy(pb);
+ error = vn_open(&nd, FREAD, 0);
+ if (error) {
+ if (lua_verbose)
+ device_printf(sc->sc_dev,
+ "error vn_open %d\n",
+ error);
+ return error;
+ }
+ error = VOP_GETATTR(nd.ni_vp, &va,
+ kauth_cred_get());
+ if (error) {
+ VOP_UNLOCK(nd.ni_vp);
+ vn_close(nd.ni_vp, FREAD,
+ kauth_cred_get());
+ if (lua_verbose)
+ device_printf(sc->sc_dev,
+ "erro VOP_GETATTR %d\n",
+ error);
+ return error;
+ }
+ if (va.va_type != VREG) {
+ VOP_UNLOCK(nd.ni_vp);
+ vn_close(nd.ni_vp, FREAD,
+ kauth_cred_get());
+ return EINVAL;
+ }
+ ls.vp = nd.ni_vp;
+ ls.off = 0L;
+ ls.size = va.va_size;
+ VOP_UNLOCK(nd.ni_vp);
+ error = lua_load(s->K->L, lua_reader, &ls,
+ strrchr(load->path, '/') + 1);
+ vn_close(nd.ni_vp, FREAD, cred);
+ switch (error) {
+ case 0: /* no error */
+ break;
+ case LUA_ERRSYNTAX:
+ if (lua_verbose)
+ device_printf(sc->sc_dev,
+ "syntax error\n");
+ return EINVAL;
+ case LUA_ERRMEM:
+ if (lua_verbose)
+ device_printf(sc->sc_dev,
+ "memory error\n");
+ return ENOMEM;
+ default:
+ if (lua_verbose)
+ device_printf(sc->sc_dev,
+ "load error %d: %s\n",
+ error,
+ lua_tostring(s->K->L, -1));
+ return EINVAL;
+ }
+ if (lua_max_instr > 0)
+ lua_sethook(s->K->L, lua_maxcount,
+ LUA_MASKCOUNT, lua_max_instr);
+ error = lua_pcall(s->K->L, 0, LUA_MULTRET, 0);
+ if (error) {
+ if (lua_verbose) {
+ device_printf(sc->sc_dev,
+ "execution error: %s\n",
+ lua_tostring(s->K->L, -1));
+ }
+ return EINVAL;
+ }
+ return 0;
+ }
+ return ENXIO;
+ }
+ return 0;
+}
+
+static int
+lua_require(lua_State *L)
+{
+ struct lua_state *s;
+ struct lua_module *m, *md;
+ const char *module;
+ char name[MAXPATHLEN];
+
+ module = lua_tostring(L, -1);
+ md = NULL;
+ LIST_FOREACH(m, &lua_modules, mod_next)
+ if (!strcmp(m->mod_name, module)) {
+ md = m;
+ break;
+ }
+
+ if (md == NULL && lua_autoload_on && strchr(module, '/') == NULL) {
+ snprintf(name, sizeof name, "lua%s", module);
+ if (lua_verbose)
+ device_printf(sc_self, "autoload %s\n", name);
+ module_autoload(name, MODULE_CLASS_LUA_BINDING);
+ LIST_FOREACH(m, &lua_modules, mod_next)
+ if (!strcmp(m->mod_name, module)) {
+ md = m;
+ break;
+ }
+ }
+
+ if (md != NULL)
+ LIST_FOREACH(s, &lua_states, lua_next)
+ if (s->K->L == L) {
+ if (lua_verbose)
+ device_printf(sc_self,
+ "require module %s\n",
+ md->mod_name);
+ md->open(L);
+ md->refcount++;
+ LIST_INSERT_HEAD(&s->lua_modules, md, mod_next);
+ return 0;
+ }
+
+ lua_pushstring(L, "module not found");
+ return lua_error(L);
+}
+
+void *
+lua_alloc(void *ud, void *ptr, size_t osize, size_t nsize)
+{
+ if (nsize == 0) {
+ if (ptr != NULL)
+ free(ptr, NULL);
+ return NULL;
+ } else
+ return realloc(ptr, nsize, ud, 0);
+}
+
+static const char *
+lua_reader(lua_State *L, void *data, size_t *size)
+{
+ struct lua_loadstate *ls;
+ static char buf[1024];
+ size_t rsiz;
+
+ ls = data;
+ if (ls->size < sizeof(buf))
+ rsiz = ls->size;
+ else
+ rsiz = sizeof(buf);
+ vn_rdwr(UIO_READ, ls->vp, buf, rsiz, ls->off, UIO_SYSSPACE,
+ 0, curlwp->l_cred, NULL, curlwp);
+ if (ls->off == 0L && lua_bytecode_on == false && buf[0] == 0x1b) {
+ *size = 0L;
+ lua_pushstring(L, "loading of bytecode is not allowed");
+ lua_error(L);
+ return NULL;
+ } else {
+ *size = rsiz;
+ ls->off += *size;
+ ls->size -= *size;
+ }
+ return buf;
+}
+
+static void
+lua_maxcount(lua_State *L, lua_Debug *d)
+{
+ lua_pushstring(L, "maximum instruction count exceeded");
+ lua_error(L);
+}
+
+int
+lua_mod_register(const char *name, int (*open)(void *))
+{
+ struct lua_module *m;
+
+ LIST_FOREACH(m, &lua_modules, mod_next)
+ if (!strcmp(m->mod_name, name))
+ return EBUSY;
+ m = malloc(sizeof(struct lua_module), NULL, M_ZERO);
+ if (m == NULL)
+ return ENOMEM;
+ strlcpy(m->mod_name, name, LUA_MAX_MODNAME);
+ m->open = open;
+ m->refcount = 0;
+ LIST_INSERT_HEAD(&lua_modules, m, mod_next);
+ if (lua_verbose)
+ device_printf(sc_self, "registered lua module %s\n", name);
+ return 0;
+}
+
+int
+lua_mod_unregister(const char *name)
+{
+ struct lua_module *m;
+
+ LIST_FOREACH(m, &lua_modules, mod_next)
+ if (!strcmp(m->mod_name, name)) {
+ if (m->refcount == 0) {
+ LIST_REMOVE(m, mod_next);
+ free(m, NULL);
+ if (lua_verbose)
+ device_printf(sc_self,
+ "unregistered lua module %s\n",
+ name);
+ return 0;
+ } else
+ return EBUSY;
+ }
+ return 0;
+}
+
+klua_State *
+klua_newstate(lua_Alloc f, void *ud, const char *name, const char *desc)
+{
+ klua_State *K;
+ struct lua_state *s;
+ struct lua_softc *sc;
+ int error;
+
+ s = malloc(sizeof(struct lua_state), NULL, M_ZERO);
+ if (s == NULL)
+ return NULL;
+
+ sc = device_private(sc_self);
+ mutex_enter(&sc->sc_state_lock);
+ while (sc->sc_state == true) {
+ error = cv_wait_sig(&sc->sc_state_cv, &sc->sc_state_lock);
+ if (error)
+ break;
+ }
+ if (!error)
+ sc->sc_state = true;
+ mutex_exit(&sc->sc_state_lock);
+
+ if (error)
+ return NULL;
+
+ K = malloc(sizeof(klua_State), NULL, M_ZERO);
+ if (K == NULL)
+ goto finish;
+ K->L = lua_newstate(f, ud);
+ K->ks_user = false;
+ if (K->L == NULL) {
+ free(K, NULL);
+ K = NULL;
+ goto finish;
+ }
+
+ strlcpy(s->lua_name, name, MAX_LUA_NAME);
+ strlcpy(s->lua_desc, desc, MAX_LUA_DESC);
+ s->K = K;
+
+ if (lua_require_on || lua_autoload_on) {
+ lua_pushcfunction(K->L, lua_require);
+ lua_setglobal(K->L, "require");
+ }
+ LIST_INSERT_HEAD(&lua_states, s, lua_next);
+
+ mutex_init(&K->ks_lock, MUTEX_DEFAULT, IPL_VM);
+ cv_init(&K->ks_inuse_cv, "luainuse");
+
+finish:
+ mutex_enter(&sc->sc_state_lock);
+ sc->sc_state = false;
+ cv_signal(&sc->sc_state_cv);
+ mutex_exit(&sc->sc_state_lock);
+ return K;
+}
+
+void
+klua_close(klua_State *K)
+{
+ struct lua_state *s;
+ struct lua_softc *sc;
+ struct lua_module *m;
+ int error;
+
+ /* Notify the Lua state that it is about to be closed */
+ if (klua_lock(K))
+ return; /* Nothing we can do about */
+
+ lua_getglobal(K->L, "onClose");
+ if (lua_isfunction(K->L, -1))
+ lua_pcall(K->L, -1, 0, 0);
+
+ /*
+ * Don't unlock, make sure no one uses the state until it is destroyed
+ * klua_unlock(K);
+ */
+
+ sc = device_private(sc_self);
+ mutex_enter(&sc->sc_state_lock);
+ while (sc->sc_state == true) {
+ error = cv_wait_sig(&sc->sc_state_cv, &sc->sc_state_lock);
+ if (error)
+ break;
+ }
+ if (!error)
+ sc->sc_state = true;
+ mutex_exit(&sc->sc_state_lock);
+
+ if (error)
+ return; /* Nothing we can do... */
+
+ LIST_FOREACH(s, &lua_states, lua_next)
+ if (s->K == K) {
+ LIST_REMOVE(s, lua_next);
+ LIST_FOREACH(m, &s->lua_modules, mod_next)
+ m->refcount--;
+ free(s, NULL);
+ }
+
+ lua_close(K->L);
+ cv_destroy(&K->ks_inuse_cv);
+ mutex_destroy(&K->ks_lock);
+ free(K, NULL);
+
+ mutex_enter(&sc->sc_state_lock);
+ sc->sc_state = false;
+ cv_signal(&sc->sc_state_cv);
+ mutex_exit(&sc->sc_state_lock);
+}
+
+static klua_State *
+klua_find(const char *name)
+{
+ struct lua_state *s;
+ struct lua_softc *sc;
+ klua_State *K;
+ int error;
+
+ K = NULL;
+ sc = device_private(sc_self);
+ mutex_enter(&sc->sc_state_lock);
+ while (sc->sc_state == true) {
+ error = cv_wait_sig(&sc->sc_state_cv, &sc->sc_state_lock);
+ if (error)
+ break;
+ }
+ if (!error)
+ sc->sc_state = true;
+ mutex_exit(&sc->sc_state_lock);
+
+ if (error)
+ return NULL;
+
+ LIST_FOREACH(s, &lua_states, lua_next)
+ if (!strcmp(s->lua_name, name)) {
+ K = s->K;
+ break;
+ }
+
+ mutex_enter(&sc->sc_state_lock);
+ sc->sc_state = false;
+ cv_signal(&sc->sc_state_cv);
+ mutex_exit(&sc->sc_state_lock);
+ return K;
+}
+
+int
+klua_lock(klua_State *K)
+{
+ int error;
+
+ error = 0;
+ mutex_enter(&K->ks_lock);
+ while (K->ks_inuse == true) {
+ error = cv_wait_sig(&K->ks_inuse_cv, &K->ks_lock);
+ if (error)
+ break;
+ }
+ if (!error)
+ K->ks_inuse = true;
+ mutex_exit(&K->ks_lock);
+
+ if (error)
+ return error;
+ return 0;
+}
+
+void
+klua_unlock(klua_State *K)
+{
+ mutex_enter(&K->ks_lock);
+ K->ks_inuse = false;
+ cv_signal(&K->ks_inuse_cv);
+ mutex_exit(&K->ks_lock);
+}
+
+MODULE(MODULE_CLASS_MISC, lua, NULL);
+
+#ifdef _MODULE
+static const struct cfiattrdata luabus_iattrdata = {
+ "luabus", 0, { { NULL, NULL, 0 },}
+};
+static const struct cfiattrdata *const lua_attrs[] = {
+ &luabus_iattrdata, NULL
+};
+CFDRIVER_DECL(lua, DV_DULL, lua_attrs);
+extern struct cfattach lua_ca;
+static int lualoc[] = {
+ -1,
+ -1,
+ -1
+};
+static struct cfdata lua_cfdata[] = {
+ {
+ .cf_name = "lua",
+ .cf_atname = "lua",
+ .cf_unit = 0,
+ .cf_fstate = FSTATE_STAR,
+ .cf_loc = lualoc,
+ .cf_flags = 0,
+ .cf_pspec = NULL,
+ },
+ { NULL, NULL, 0, FSTATE_NOTFOUND, NULL, 0, NULL }
+};
+#endif
+
+static int
+lua_modcmd(modcmd_t cmd, void *opaque)
+{
+#ifdef _MODULE
+ devmajor_t cmajor, bmajor;
+ int error = 0;
+
+ cmajor = bmajor = NODEVMAJOR;
+#endif
+ switch (cmd) {
+ case MODULE_CMD_INIT:
+#ifdef _MODULE
+ error = config_cfdriver_attach(&lua_cd);
+ if (error)
+ return error;
+
+ error = config_cfattach_attach(lua_cd.cd_name,
+ &lua_ca);
+ if (error) {
+ config_cfdriver_detach(&lua_cd);
+ aprint_error("%s: unable to register cfattach\n",
+ lua_cd.cd_name);
+ return error;
+ }
+ error = config_cfdata_attach(lua_cfdata, 1);
+ if (error) {
+ config_cfattach_detach(lua_cd.cd_name,
+ &lua_ca);
+ config_cfdriver_detach(&lua_cd);
+ aprint_error("%s: unable to register cfdata\n",
+ lua_cd.cd_name);
+ return error;
+ }
+ error = devsw_attach(lua_cd.cd_name, NULL, &bmajor,
+ &lua_cdevsw, &cmajor);
+ if (error) {
+ aprint_error("%s: unable to register devsw\n",
+ lua_cd.cd_name);
+ config_cfattach_detach(lua_cd.cd_name, &lua_ca);
+ config_cfdriver_detach(&lua_cd);
+ return error;
+ }
+ config_attach_pseudo(lua_cfdata);
+#endif
+ return 0;
+ case MODULE_CMD_FINI:
+#ifdef _MODULE
+ error = config_cfdata_detach(lua_cfdata);
+ if (error)
+ return error;
+
+ config_cfattach_detach(lua_cd.cd_name, &lua_ca);
+ config_cfdriver_detach(&lua_cd);
+ devsw_detach(NULL, &lua_cdevsw);
+#endif
+ return 0;
+ case MODULE_CMD_AUTOUNLOAD:
+ /* no auto-unload */
+ return EBUSY;
+ default:
+ return ENOTTY;
+ }
+}