* Florian Forster <octo at collectd.org>
**/
+/* <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 "common.h"
#include <lua.h>
#include <lauxlib.h>
#include <lualib.h>
+#include "utils_lua.h"
+
+#if defined(COLLECT_DEBUG) && COLLECT_DEBUG && defined(__GNUC__) && __GNUC__
+# undef sprintf
+# pragma GCC poison sprintf
+#endif
typedef struct lua_script_s {
char *script_path;
{
lua_State *lua_state;
char *lua_function_name;
+ int callback_id;
};
typedef struct clua_read_function_s clua_read_function_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 */
+
+ /* 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 */
+
+static int clua_load_callback (lua_State *l, int callback_id) /* {{{ */
+{
+ 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);
+ }
+
+ /* Remove table */
+ lua_remove (l, /* idx = */ -2); /* -1 */
+ return (0);
+} /* }}} int clua_load_callback */
+
static int clua_read (user_data_t *ud) /* {{{ */
{
clua_read_function_t *rf = ud->data;
int status;
- /* Load the function to the stack */
- lua_pushstring (rf->lua_state, rf->lua_function_name);
- lua_gettable (rf->lua_state, LUA_REGISTRYINDEX);
-
- if (!lua_isfunction (rf->lua_state, /* stack pos = */ -1))
+ status = clua_load_callback (rf->lua_state, rf->callback_id);
+ if (status != 0)
{
- ERROR ("lua plugin: Unable to lookup the read function \"%s\".",
- rf->lua_function_name);
- /* pop the value again */
- lua_settop (rf->lua_state, -2);
+ ERROR ("lua plugin: Unable to load callback \"%s\" (id %i).",
+ rf->lua_function_name, rf->callback_id);
return (-1);
}
+ /* +1 */
- lua_call (rf->lua_state, /* nargs = */ 0, /* nresults = */ 1);
+ lua_call (rf->lua_state, /* nargs = */ 0, /* nresults = */ 1); /* +1 */
- if (lua_isnumber (rf->lua_state, -1))
+ if (lua_isnumber (rf->lua_state, /* idx = */ -1))
{
- status = (int) lua_tonumber (rf->lua_state, -1);
+ status = (int) lua_tointeger (rf->lua_state, /* idx = */ -1);
}
else
{
- ERROR ("lua plugin: Read function \"%s\" did not return a numeric status.",
- rf->lua_function_name);
+ ERROR ("lua plugin: Read function \"%s\" (id %i) did not return a numeric status.",
+ rf->lua_function_name, rf->callback_id);
status = -1;
}
- /* pop the value */
- lua_settop (rf->lua_state, -2);
+ /* pop return value and function */
+ lua_settop (rf->lua_state, /* idx = */ -2); /* -2 */
return (status);
} /* }}} int clua_read */
RETURN_LUA (l, 0);
} /* }}} int lua_cb_log */
+static int lua_cb_dispatch_values (lua_State *l) /* {{{ */
+{
+ 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);
+ }
+
+ 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);
+ }
+
+ 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) /* {{{ */
{
- static int count = 0;
int nargs = lua_gettop (l); /* number of arguments */
clua_read_function_t *rf;
- int num = count++; /* XXX FIXME: Not thread-safe! */
- char function_name[64];
+ int callback_id;
+ char function_name[DATA_MAX_NAME_LEN] = "";
if (nargs != 1)
{
RETURN_LUA (l, -1);
}
- /* If the argument is a string, assume it's a global function and try to look
- * it up. */
if (lua_isstring (l, /* stack pos = */ 1))
- lua_gettable (l, LUA_GLOBALSINDEX);
+ {
+ const char *tmp = lua_tostring (l, /* idx = */ 1);
+ ssnprintf (function_name, sizeof (function_name), "lua/%s", tmp);
+ }
- if (!lua_isfunction (l, /* stack pos = */ 1))
+ callback_id = clua_store_callback (l, /* idx = */ 1);
+ if (callback_id < 0)
{
- WARNING ("lua plugin: The first argument of collectd_register_read() "
- "must be a function.");
+ ERROR ("lua plugin: Storing callback function failed.");
RETURN_LUA (l, -1);
}
- ssnprintf (function_name, sizeof (function_name), "collectd.read_func_%i", num);
-
- /* Push the name of the global variable */
- lua_pushstring (l, function_name);
- /* Push the name down to the first position */
- lua_insert (l, 1);
- /* Now set the global variable called "collectd". */
- lua_settable (l, LUA_REGISTRYINDEX);
+ if (function_name[0] == 0)
+ ssnprintf (function_name, sizeof (function_name), "lua/callback_%i", callback_id);
rf = malloc (sizeof (*rf));
if (rf == NULL)
else
{
user_data_t ud = { rf, /* free func */ NULL /* FIXME */ };
- char cb_name[DATA_MAX_NAME_LEN];
memset (rf, 0, sizeof (*rf));
rf->lua_state = l;
+ rf->callback_id = callback_id;
rf->lua_function_name = strdup (function_name);
- ssnprintf (cb_name, sizeof (cb_name), "lua/read_func_%i", num);
-
plugin_register_complex_read (/* group = */ "lua",
- /* name = */ cb_name,
+ /* name = */ function_name,
/* callback = */ clua_read,
/* interval = */ NULL,
/* user_data = */ &ud);
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 }
};
-/* 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 lua_load_libs[] =
-{
- { LUA_COLIBNAME, luaopen_base },
- /* { "luaopen_loadlib", luaopen_loadlib }, */
-#if COLLECT_DEBUG
- { LUA_DBLIBNAME, luaopen_debug },
-#endif
- { LUA_TABLIBNAME, luaopen_table },
- { LUA_IOLIBNAME, luaopen_io },
- { LUA_STRLIBNAME, luaopen_string },
- { LUA_MATHLIBNAME, luaopen_math }
-};
-
static void lua_script_free (lua_script_t *script) /* {{{ */
{
lua_script_t *next;
return (-1);
}
- /* Open up all the Lua libraries declared above. */
- for (i = 0; i < STATIC_ARRAY_SIZE (lua_load_libs); i++)
- {
- int status;
-
- status = (*lua_load_libs[i].func) (script->lua_state);
- if (status != 0)
- WARNING ("lua plugin: Loading library \"%s\" failed.",
- lua_load_libs[i].name);
- }
+ /* 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++)
return (-1);
}
- status = lua_dofile (script->lua_state, script->script_path);
+ 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;
- switch (status)
- {
- case LUA_ERRSYNTAX: errmsg = "Syntax error"; break;
- case LUA_ERRFILE: errmsg = "File I/O error"; break;
- case LUA_ERRMEM: errmsg = "Memory allocation error"; break;
- default: errmsg = "Unexpected error";
- }
+ errmsg = lua_tostring (script->lua_state, /* stack pos = */ -1);
- ERROR ("lua plugin: Loading script \"%s\" failed: %s",
- script->script_path, errmsg);
+ 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);