/**
* collectd - src/lua.c
* Copyright (C) 2010 Julien Ammous
+ * Copyright (C) 2010 Florian Forster
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as published by
*
* Authors:
* Julien Ammous
+ * Florian Forster <octo at collectd.org>
**/
-#include <unistd.h> // access
-
-/* Include the Lua API header files. */
-#define lua_c
-#include <lua.h>
-#include <lauxlib.h>
-#include <lualib.h>
+/* <lua5.1/luaconf.h> defines a macro using "sprintf". Although not used here,
+ * GCC will complain about the macro definition. */
+#define DONT_POISON_SPRINTF_YET
#include "collectd.h"
#include "plugin.h"
#include "configfile.h"
#include "utils_cache.h"
-#include "lua_exports.c"
+/* Include the Lua API header files. */
+#include <lua.h>
+#include <lauxlib.h>
+#include <lualib.h>
+#include "utils_lua.h"
+
+#include <pthread.h>
+
+#if defined(COLLECT_DEBUG) && COLLECT_DEBUG && defined(__GNUC__) && __GNUC__
+# undef sprintf
+# pragma GCC poison sprintf
+#endif
-typedef struct lua_script_s {
+struct lua_script_s;
+typedef struct lua_script_s lua_script_t;
+struct lua_script_s
+{
char *script_path;
lua_State *lua_state;
- struct lua_script_s *next;
-} lua_script_t;
+ lua_script_t *next;
+};
+
+struct clua_callback_data_s
+{
+ lua_State *lua_state;
+ char *lua_function_name;
+ pthread_mutex_t lock;
+ int callback_id;
+};
+typedef struct clua_callback_data_s clua_callback_data_t;
+
+struct lua_c_functions_s
+{
+ char *name;
+ lua_CFunction func;
+};
+typedef struct lua_c_functions_s lua_c_functions_t;
+
+static char base_path[PATH_MAX + 1] = "";
+static lua_script_t *scripts = NULL;
+
+static int clua_store_callback (lua_State *l, int idx) /* {{{ */
+{
+ static int callback_num = 0;
+ int callback_id;
+
+ /* XXX FIXME: Not thread-safe! */
+ callback_id = callback_num++;
+
+ if (idx < 0)
+ idx += lua_gettop (l) + 1;
+
+ lua_getfield (l, LUA_REGISTRYINDEX, "collectd_callbacks"); /* +1 = 1 */
+ if (!lua_istable (l, /* idx = */ -1))
+ {
+ lua_pop (l, /* nelems = */ 1); /* -1 = 0 */
+ lua_newtable (l); /* +1 = 1 */
+ lua_pushvalue (l, -1); /* +1 = 2 */
+ lua_setfield (l, LUA_REGISTRYINDEX, "collectd_callbacks"); /* -1 = 1 */
+ }
+ /* The table is now on top of the stack */
+ lua_pushinteger (l, (lua_Integer) callback_id); /* +1 = 2 */
-static char base_path[MAXPATHLEN];
-static lua_script_t scripts;
+ /* Copy the function pointer */
+ lua_pushvalue (l, idx); /* +1 = 3 */
+ /* Lookup function if it's a string */
+ if (lua_isstring (l, /* idx = */ -1))
+ lua_gettable (l, LUA_GLOBALSINDEX); /* +-0 = 3 */
+ if (!lua_isfunction (l, /* idx = */ -1))
+ {
+ lua_pop (l, /* nelems = */ 3); /* -3 = 0 */
+ return (-1);
+ }
+ lua_settable (l, /* idx = */ -3); /* -2 = 1 */
+ lua_pop (l, /* nelems = */ 1); /* -1 = 0 */
+ return (callback_id);
+} /* }}} int clua_store_callback */
-/* Declare the Lua libraries we wish to use. */
-/* Note: If you are opening and running a file containing Lua code */
-/* using 'lua_dofile(l, "myfile.lua") - you must delcare all the libraries */
-/* used in that file here also. */
-static const luaL_reg lualibs[] =
+static int clua_load_callback (lua_State *l, int callback_id) /* {{{ */
{
- // { "base", luaopen_base },
- { NULL, NULL }
-};
+ lua_getfield (l, LUA_REGISTRYINDEX, "collectd_callbacks"); /* +1 */
+ if (!lua_istable (l, /* idx = */ -1))
+ {
+ lua_pop (l, /* nelems = */ 1); /* -1 */
+ return (-1);
+ }
+
+ lua_pushinteger (l, (lua_Integer) callback_id); /* + 1 */
+ lua_gettable (l, /* idx = */ -2); /* +-0 */
+
+ if (!lua_isfunction (l, -1))
+ {
+ lua_pop (l, /* nelems = */ 2); /* -2 */
+ return (-1);
+ }
-/* A function to open up all the Lua libraries you declared above. */
-static void openlualibs(lua_State *l)
+ /* Remove table */
+ lua_remove (l, /* idx = */ -2); /* -1 */
+ return (0);
+} /* }}} int clua_load_callback */
+
+static int clua_read (user_data_t *ud) /* {{{ */
{
- const luaL_reg *lib;
- for( lib = lualibs; lib->func != NULL; lib++) {
- lib->func(l);
- lua_settop(l, 0);
+ clua_callback_data_t *cb = ud->data;
+ int status;
+
+ status = clua_load_callback (cb->lua_state, cb->callback_id);
+ if (status != 0)
+ {
+ ERROR ("lua plugin: Unable to load callback \"%s\" (id %i).",
+ cb->lua_function_name, cb->callback_id);
+ return (-1);
}
-}
+ /* +1 */
+ lua_call (cb->lua_state, /* nargs = */ 0, /* nresults = */ 1); /* +1 */
+ if (lua_isnumber (cb->lua_state, /* idx = */ -1))
+ {
+ status = (int) lua_tointeger (cb->lua_state, /* idx = */ -1);
+ }
+ else
+ {
+ ERROR ("lua plugin: Read function \"%s\" (id %i) did not return a numeric status.",
+ cb->lua_function_name, cb->callback_id);
+ status = -1;
+ }
+ /* pop return value and function */
+ lua_settop (cb->lua_state, /* idx = */ -2); /* -2 */
+ return (status);
+} /* }}} int clua_read */
+static int clua_write (const data_set_t *ds, const value_list_t *vl, /* {{{ */
+ user_data_t *ud)
+{
+ clua_callback_data_t *cb = ud->data;
+ int status;
-static int lua_config_base_path (const oconfig_item_t *ci)
+ pthread_mutex_lock (&cb->lock);
+
+ status = clua_load_callback (cb->lua_state, cb->callback_id);
+ if (status != 0)
+ {
+ ERROR ("lua plugin: Unable to load callback \"%s\" (id %i).",
+ cb->lua_function_name, cb->callback_id);
+ pthread_mutex_unlock (&cb->lock);
+ return (-1);
+ }
+ /* +1 = 1 */
+
+ status = luaC_pushvaluelist (cb->lua_state, ds, vl);
+ if (status != 0)
+ {
+ lua_pop (cb->lua_state, /* nelems = */ 1); /* -1 = 0 */
+ pthread_mutex_unlock (&cb->lock);
+ ERROR ("lua plugin: luaC_pushvaluelist failed.");
+ return (-1);
+ }
+ /* +1 = 2 */
+
+ status = lua_pcall (cb->lua_state,
+ /* nargs = */ 1,
+ /* nresults = */ 1,
+ /* errfunc = */ 0); /* -2+1 = 1 */
+ if (status != 0)
+ {
+ const char *errmsg = lua_tostring (cb->lua_state, /* idx = */ -1);
+ if (errmsg == NULL)
+ ERROR ("lua plugin: Calling the write callback failed. "
+ "In addition, retrieving the error message failed.");
+ else
+ ERROR ("lua plugin: Calling the write callback failed:\n%s", errmsg);
+ lua_pop (cb->lua_state, /* nelems = */ 1); /* -1 = 0 */
+ pthread_mutex_unlock (&cb->lock);
+ return (-1);
+ }
+
+ if (!lua_isnumber (cb->lua_state, /* idx = */ -1))
+ {
+ ERROR ("lua plugin: Write function \"%s\" (id %i) did not return a numeric value.",
+ cb->lua_function_name, cb->callback_id);
+ status = -1;
+ }
+ else
+ {
+ status = (int) lua_tointeger (cb->lua_state, /* idx = */ -1);
+ }
+
+ lua_pop (cb->lua_state, /* nelems = */ 1); /* -1 = 0 */
+ pthread_mutex_unlock (&cb->lock);
+ return (status);
+} /* }}} int clua_write */
+
+/* Cleans up the stack, pushes the return value as a number onto the stack and
+ * returns the number of values returned (1). */
+#define RETURN_LUA(l,status) do { \
+ lua_State *_l_state = (l); \
+ lua_settop (_l_state, 0); \
+ lua_pushnumber (_l_state, (lua_Number) (status)); \
+ return (1); \
+} while (0)
+
+/*
+ * Exported functions
+ */
+static int lua_cb_log (lua_State *l) /* {{{ */
{
- if( (ci->values_num != 1) || (ci->values[0].type != OCONFIG_TYPE_STRING) ){
- ERROR("lua plugin: The '%s' config option requires a single string argument", ci->key);
- return -1;
+ int nargs = lua_gettop (l); /* number of arguments */
+ int severity;
+ const char *msg;
+
+ if (nargs != 2)
+ {
+ WARNING ("lua plugin: collectd_log() called with an invalid number of arguments (%i).",
+ nargs);
+ RETURN_LUA (l, -1);
}
-
- strncpy(base_path, ci->values[0].value.string, sizeof(base_path));
-
- /* add ending slash if not provided */
- if( base_path[strlen(base_path) - 1] != '/' ){
- base_path[strlen(base_path)] = '/';
+
+ if (!lua_isnumber (l, 1))
+ {
+ WARNING ("lua plugin: The first argument to collectd_log() must be a number.");
+ RETURN_LUA (l, -1);
}
-
- INFO("lua plugin: BasePath = '%s'", base_path);
- return 0;
-}
-static int lua_config_script (const oconfig_item_t *ci)
+ if (!lua_isstring (l, 2))
+ {
+ WARNING ("lua plugin: The second argument to collectd_log() must be a string.");
+ RETURN_LUA (l, -1);
+ }
+
+ severity = (int) lua_tonumber (l, /* stack pos = */ 1);
+ if ((severity != LOG_ERR)
+ && (severity != LOG_WARNING)
+ && (severity != LOG_NOTICE)
+ && (severity != LOG_INFO)
+ && (severity != LOG_DEBUG))
+ severity = LOG_ERR;
+
+ msg = lua_tostring (l, 2);
+ if (msg == NULL)
+ {
+ ERROR ("lua plugin: lua_tostring failed.");
+ RETURN_LUA (l, -1);
+ }
+
+ plugin_log (severity, "%s", msg);
+
+ RETURN_LUA (l, 0);
+} /* }}} int lua_cb_log */
+
+static int lua_cb_dispatch_values (lua_State *l) /* {{{ */
{
- lua_script_t *script = &scripts;
-
- if( (ci->values_num != 1) || (ci->values[0].type != OCONFIG_TYPE_STRING) ){
- ERROR("lua plugin: The '%s' config option requires a single string argument", ci->key);
- return -1;
+ value_list_t *vl;
+ int nargs = lua_gettop (l); /* number of arguments */
+ char identifier[6 * DATA_MAX_NAME_LEN];
+
+ if (nargs != 1)
+ {
+ WARNING ("lua plugin: collectd_dispatch_values() called "
+ "with an invalid number of arguments (%i).", nargs);
+ RETURN_LUA (l, -1);
}
-
- /* find a free slot for the structure */
- while( script->next != NULL ){
- script = script->next;
+
+ if (!lua_istable (l, 1))
+ {
+ WARNING ("lua plugin: The first argument to collectd_dispatch_values() "
+ "must be a \"value list\" (i.e. a table).");
+ RETURN_LUA (l, -1);
}
-
- /* build full path : base_path + given path + \0 */
- script->script_path = malloc(
- strlen(base_path) +
- strlen(ci->values[0].value.string) + 1
- );
-
- strncpy(script->script_path, base_path, sizeof(script->script_path));
- strncpy(script->script_path + strlen(base_path), ci->values[0].value.string, sizeof(script->script_path));
-
- /* check if the file exists and we can read it */
- if( access(script->script_path, R_OK) == -1 ) {
- ERROR("lua plugin: Cannot read file '%s' : %s", script->script_path, strerror(errno));
- free(script->script_path);
- return -1;
+
+ vl = luaC_tovaluelist (l, /* idx = */ -1);
+ if (vl == NULL)
+ {
+ WARNING ("lua plugin: ltoc_value_list failed.");
+ RETURN_LUA (l, -1);
}
-
+
+ FORMAT_VL (identifier, sizeof (identifier), vl);
+
+ DEBUG ("lua plugin: collectd_dispatch_values: Received value list \"%s\", time %.3f, interval %.3f.",
+ identifier, CDTIME_T_TO_DOUBLE (vl->time), CDTIME_T_TO_DOUBLE (vl->interval));
+
+ sfree (vl->values);
+ sfree (vl);
+ RETURN_LUA (l, 0);
+} /* }}} lua_cb_dispatch_values */
+
+static int lua_cb_register_read (lua_State *l) /* {{{ */
+{
+ int nargs = lua_gettop (l); /* number of arguments */
+ clua_callback_data_t *cb;
+ user_data_t ud;
+
+ int callback_id;
+ char function_name[DATA_MAX_NAME_LEN] = "";
+
+ if (nargs != 1)
+ {
+ WARNING ("lua plugin: collectd_register_read() called with an invalid "
+ "number of arguments (%i).", nargs);
+ RETURN_LUA (l, -1);
+ }
+
+ if (lua_isstring (l, /* stack pos = */ 1))
+ {
+ const char *tmp = lua_tostring (l, /* idx = */ 1);
+ ssnprintf (function_name, sizeof (function_name), "lua/%s", tmp);
+ }
+
+ callback_id = clua_store_callback (l, /* idx = */ 1);
+ if (callback_id < 0)
+ {
+ ERROR ("lua plugin: Storing callback function failed.");
+ RETURN_LUA (l, -1);
+ }
+
+ if (function_name[0] == 0)
+ ssnprintf (function_name, sizeof (function_name), "lua/callback_%i", callback_id);
+
+ cb = malloc (sizeof (*cb));
+ if (cb == NULL)
+ {
+ ERROR ("lua plugin: malloc failed.");
+ RETURN_LUA (l, -1);
+ }
+
+ memset (cb, 0, sizeof (*cb));
+ cb->lua_state = l;
+ cb->callback_id = callback_id;
+ cb->lua_function_name = strdup (function_name);
+
+ ud.data = cb;
+ ud.free_func = NULL; /* FIXME */
+
+ plugin_register_complex_read (/* group = */ "lua",
+ /* name = */ function_name,
+ /* callback = */ clua_read,
+ /* interval = */ NULL,
+ /* user_data = */ &ud);
+
+ DEBUG ("lua plugin: Successful call to lua_cb_register_read().");
+
+ RETURN_LUA (l, 0);
+} /* }}} int lua_cb_register_read */
+
+static int lua_cb_register_write (lua_State *l) /* {{{ */
+{
+ int nargs = lua_gettop (l); /* number of arguments */
+ clua_callback_data_t *cb;
+ user_data_t ud;
+
+ int callback_id;
+ char function_name[DATA_MAX_NAME_LEN] = "";
+
+ if (nargs != 1)
+ {
+ WARNING ("lua plugin: collectd_register_read() called with an invalid "
+ "number of arguments (%i).", nargs);
+ RETURN_LUA (l, -1);
+ }
+
+ if (lua_isstring (l, /* stack pos = */ 1))
+ {
+ const char *tmp = lua_tostring (l, /* idx = */ 1);
+ ssnprintf (function_name, sizeof (function_name), "lua/%s", tmp);
+ }
+
+ callback_id = clua_store_callback (l, /* idx = */ 1);
+ if (callback_id < 0)
+ {
+ ERROR ("lua plugin: Storing callback function failed.");
+ RETURN_LUA (l, -1);
+ }
+
+ if (function_name[0] == 0)
+ ssnprintf (function_name, sizeof (function_name), "lua/callback_%i", callback_id);
+
+ cb = malloc (sizeof (*cb));
+ if (cb == NULL)
+ {
+ ERROR ("lua plugin: malloc failed.");
+ RETURN_LUA (l, -1);
+ }
+
+ memset (cb, 0, sizeof (*cb));
+ cb->lua_state = l;
+ cb->callback_id = callback_id;
+ cb->lua_function_name = strdup (function_name);
+ pthread_mutex_init (&cb->lock, /* attr = */ NULL);
+
+ ud.data = cb;
+ ud.free_func = NULL; /* FIXME */
+
+ plugin_register_write (/* name = */ function_name,
+ /* callback = */ clua_write,
+ /* user_data = */ &ud);
+
+ DEBUG ("lua plugin: Successful call to lua_cb_register_write().");
+
+ RETURN_LUA (l, 0);
+} /* }}} int lua_cb_register_write */
+
+static lua_c_functions_t lua_c_functions[] =
+{
+ { "collectd_log", lua_cb_log },
+ { "collectd_dispatch_values", lua_cb_dispatch_values },
+ { "collectd_register_read", lua_cb_register_read },
+ { "collectd_register_write", lua_cb_register_write }
+};
+
+static void lua_script_free (lua_script_t *script) /* {{{ */
+{
+ lua_script_t *next;
+
+ if (script == NULL)
+ return;
+
+ next = script->next;
+
+ if (script->lua_state != NULL)
+ {
+ lua_close (script->lua_state);
+ script->lua_state = NULL;
+ }
+
+ sfree (script->script_path);
+ sfree (script);
+
+ lua_script_free (next);
+} /* }}} void lua_script_free */
+
+static int lua_script_init (lua_script_t *script) /* {{{ */
+{
+ size_t i;
+
+ memset (script, 0, sizeof (*script));
+ script->script_path = NULL;
+ script->next = NULL;
+
/* initialize the lua context */
script->lua_state = lua_open();
-
- openlualibs(script->lua_state);
-
- if( register_exported_functions(script->lua_state) != 0 ) {
- ERROR("lua plugin: Cannot register exported functions, aborting");
- free(script->script_path);
- return -1;
+ if (script->lua_state == NULL)
+ {
+ ERROR ("lua plugin: lua_open failed.");
+ return (-1);
}
-
- /* and try to load the file */
- if( luaL_dofile(script->lua_state, "script.lua") != 0 ) {
- ERROR("lua plugin: error while loading '%s' => %s\n", script->script_path, lua_tostring(script->lua_state, -1));
- free(script->script_path);
- return -1;
+
+ /* Open up all the standard Lua libraries. */
+ luaL_openlibs (script->lua_state);
+
+ /* Register all the functions we implement in C */
+ for (i = 0; i < STATIC_ARRAY_SIZE (lua_c_functions); i++)
+ lua_register (script->lua_state,
+ lua_c_functions[i].name, lua_c_functions[i].func);
+
+ return (0);
+} /* }}} int lua_script_init */
+
+static int lua_script_load (const char *script_path) /* {{{ */
+{
+ lua_script_t *script;
+ int status;
+
+ script = malloc (sizeof (*script));
+ if (script == NULL)
+ {
+ ERROR ("lua plugin: malloc failed.");
+ return (-1);
}
-
- INFO("lua plugin: file '%s' loaded succesfully", script->script_path);
+
+ status = lua_script_init (script);
+ if (status != 0)
+ {
+ lua_script_free (script);
+ return (status);
+ }
+
+ script->script_path = strdup (script_path);
+ if (script->script_path == NULL)
+ {
+ ERROR ("lua plugin: strdup failed.");
+ lua_script_free (script);
+ return (-1);
+ }
+
+ status = luaL_loadfile (script->lua_state, script->script_path);
+ if (status != 0)
+ {
+ ERROR ("lua plugin: luaL_loadfile failed with status %i", status);
+ lua_script_free (script);
+ return (-1);
+ }
+
+ status = lua_pcall (script->lua_state,
+ /* nargs = */ 0,
+ /* nresults = */ LUA_MULTRET,
+ /* errfunc = */ 0);
+ if (status != 0)
+ {
+ const char *errmsg;
+
+ errmsg = lua_tostring (script->lua_state, /* stack pos = */ -1);
+
+ if (errmsg == NULL)
+ ERROR ("lua plugin: lua_pcall failed with status %i. "
+ "In addition, no error message could be retrieved from the stack.",
+ status);
+ else
+ ERROR ("lua plugin: Executing script \"%s\" failed:\n%s",
+ script->script_path, errmsg);
+
+ lua_script_free (script);
+ return (-1);
+ }
+
+ /* Append this script to the global list of scripts. */
+ if (scripts == NULL)
+ {
+ scripts = script;
+ }
+ else
+ {
+ lua_script_t *last;
+
+ last = scripts;
+ while (last->next != NULL)
+ last = last->next;
+
+ last->next = script;
+ }
+
+ return (0);
+} /* }}} int lua_script_load */
+
+static int lua_config_base_path (const oconfig_item_t *ci) /* {{{ */
+{
+ int status;
+ size_t len;
+
+ status = cf_util_get_string_buffer (ci, base_path, sizeof (base_path));
+ if (status != 0)
+ return (status);
+
+ len = strlen (base_path);
+ while ((len > 0) && (base_path[len - 1] == '/'))
+ {
+ len--;
+ base_path[len] = 0;
+ }
+
+ DEBUG ("lua plugin: base_path = \"%s\";", base_path);
+
+ return (0);
+} /* }}} int lua_config_base_path */
+
+static int lua_config_script (const oconfig_item_t *ci) /* {{{ */
+{
+ char rel_path[PATH_MAX + 1];
+ char abs_path[PATH_MAX + 1];
+ int status;
+
+ status = cf_util_get_string_buffer (ci, rel_path, sizeof (rel_path));
+ if (status != 0)
+ return (status);
+
+ if (base_path[0] == 0)
+ sstrncpy (abs_path, rel_path, sizeof (abs_path));
+ else
+ ssnprintf (abs_path, sizeof (abs_path), "%s/%s", base_path, rel_path);
+
+ DEBUG ("lua plugin: abs_path = \"%s\";", abs_path);
+
+ status = lua_script_load (abs_path);
+ if (status != 0)
+ return (status);
+
+ INFO("lua plugin: File \"%s\" loaded succesfully", abs_path);
return 0;
-}
+} /* }}} int lua_config_script */
-// <Plugin lua>
-// BasePath /
-// Script script1.lua
-// Script script2.lua
-// </Plugin>
-static int lua_config(oconfig_item_t *ci)
+/*
+ * <Plugin lua>
+ * BasePath "/"
+ * Script "script1.lua"
+ * Script "script2.lua"
+ * </Plugin>
+ */
+static int lua_config (oconfig_item_t *ci) /* {{{ */
{
int i;
}
return 0;
-}
+} /* }}} int lua_config */
-static int lua_init()
+static int lua_shutdown (void) /* {{{ */
{
- INFO("Lua plugin loaded.");
-
- return 0;
-}
+ lua_script_free (scripts);
+ scripts = NULL;
+
+ return (0);
+} /* }}} int lua_shutdown */
void module_register()
{
plugin_register_complex_config("lua", lua_config);
- plugin_register_init("lua", lua_init);
+ plugin_register_shutdown("lua", lua_shutdown);
}
-
-
+/* vim: set sw=2 sts=2 et fdm=marker : */
projects / collectd.git / blobdiff