/* * LANES.C Copyright (c) 2007-08, Asko Kauppi * Copyright (C) 2009-14, Benoit Germain * * Multithreading in Lua. * * History: * See CHANGES * * Platforms (tested internally): * OS X (10.5.7 PowerPC/Intel) * Linux x86 (Ubuntu 8.04) * Win32 (Windows XP Home SP2, Visual C++ 2005/2008 Express) * * Platforms (tested externally): * Win32 (MSYS) by Ross Berteig. * * Platforms (testers appreciated): * Win64 - should work??? * Linux x64 - should work * FreeBSD - should work * QNX - porting shouldn't be hard * Sun Solaris - porting shouldn't be hard * * References: * "Porting multithreaded applications from Win32 to Mac OS X": * * * Pthreads: * * * MSDN: * * * * Defines: * -DLINUX_SCHED_RR: all threads are lifted to SCHED_RR category, to * allow negative priorities [-3,-1] be used. Even without this, * using priorities will require 'sudo' privileges on Linux. * * -DUSE_PTHREAD_TIMEDJOIN: use 'pthread_timedjoin_np()' for waiting * for threads with a timeout. This changes the thread cleanup * mechanism slightly (cleans up at the join, not once the thread * has finished). May or may not be a good idea to use it. * Available only in selected operating systems (Linux). * * Bugs: * * To-do: * * Make waiting threads cancellable. * ... */ char const* VERSION = "3.8.3"; /* =============================================================================== Copyright (C) 2007-10 Asko Kauppi 2011-14 Benoit Germain Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. =============================================================================== */ #include #include #include #include #include "lua.h" #include "lauxlib.h" #include "threading.h" #include "tools.h" #include "keeper.h" #include "lanes.h" #if !(defined( PLATFORM_XBOX) || defined( PLATFORM_WIN32) || defined( PLATFORM_POCKETPC)) # include #endif /* geteuid() */ #ifdef PLATFORM_LINUX # include # include #endif /* * Do we want to activate full lane tracking feature? (EXPERIMENTAL) */ #define HAVE_LANE_TRACKING 1 /* Do you want full call stacks, or just the line where the error happened? * * TBD: The full stack feature does not seem to work (try 'make error'). */ #define ERROR_FULL_STACK 1 // must be either 0 or 1 as we do some index arithmetics with it! /* * Lane cancellation request modes */ enum e_cancel_request { CANCEL_NONE, // no pending cancel request CANCEL_SOFT, // user wants the lane to cancel itself manually on cancel_test() CANCEL_HARD // user wants the lane to be interrupted (meaning code won't return from those functions) from inside linda:send/receive calls }; // NOTE: values to be changed by either thread, during execution, without // locking, are marked "volatile" // struct s_lane { THREAD_T thread; // // M: sub-thread OS thread // S: not used char const* debug_name; lua_State* L; // // M: prepares the state, and reads results // S: while S is running, M must keep out of modifying the state volatile enum e_status status; // // M: sets to PENDING (before launching) // S: updates -> RUNNING/WAITING -> DONE/ERROR_ST/CANCELLED SIGNAL_T * volatile waiting_on; // // When status is WAITING, points on the linda's signal the thread waits on, else NULL volatile enum e_cancel_request cancel_request; // // M: sets to FALSE, flags TRUE for cancel request // S: reads to see if cancel is requested #if THREADWAIT_METHOD == THREADWAIT_CONDVAR SIGNAL_T done_signal; // // M: Waited upon at lane ending (if Posix with no PTHREAD_TIMEDJOIN) // S: sets the signal once cancellation is noticed (avoids a kill) MUTEX_T done_lock; // // Lock required by 'done_signal' condition variable, protecting // lane status changes to DONE/ERROR_ST/CANCELLED. #endif // THREADWAIT_METHOD == THREADWAIT_CONDVAR volatile enum { NORMAL, // normal master side state KILLED // issued an OS kill } mstatus; // // M: sets to NORMAL, if issued a kill changes to KILLED // S: not used struct s_lane* volatile selfdestruct_next; // // M: sets to non-NULL if facing lane handle '__gc' cycle but the lane // is still running // S: cleans up after itself if non-NULL at lane exit #if HAVE_LANE_TRACKING struct s_lane* volatile tracking_next; #endif // HAVE_LANE_TRACKING // // For tracking only }; // To allow free-running threads (longer lifespan than the handle's) // 'struct s_lane' are malloc/free'd and the handle only carries a pointer. // This is not deep userdata since the handle's not portable among lanes. // #define lua_toLane( L, i) (*((struct s_lane**) luaL_checkudata( L, i, "Lane"))) #define CANCEL_TEST_KEY ((void*)get_lane_from_registry) // used as registry key static inline struct s_lane* get_lane_from_registry( lua_State* L) { struct s_lane* s; STACK_GROW( L, 1); STACK_CHECK( L); lua_pushlightuserdata( L, CANCEL_TEST_KEY); lua_rawget( L, LUA_REGISTRYINDEX); s = lua_touserdata( L, -1); // lightuserdata (true 's_lane' pointer) / nil lua_pop( L, 1); STACK_END( L, 0); return s; } // intern the debug name in the specified lua state so that the pointer remains valid when the lane's state is closed static void securize_debug_threadname( lua_State* L, struct s_lane* s) { STACK_CHECK( L); STACK_GROW( L, 3); lua_getuservalue( L, 1); lua_newtable( L); s->debug_name = lua_pushstring( L, s->debug_name); lua_rawset( L, -3); lua_pop( L, 1); STACK_END( L, 0); } /* * Check if the thread in question ('L') has been signalled for cancel. * * Called by cancellation hooks and/or pending Linda operations (because then * the check won't affect performance). * * Returns TRUE if any locks are to be exited, and 'cancel_error()' called, * to make execution of the lane end. */ static inline enum e_cancel_request cancel_test( lua_State* L) { struct s_lane* const s = get_lane_from_registry( L); // 's' is NULL for the original main state (and no-one can cancel that) return s ? s->cancel_request : CANCEL_NONE; } #define CANCEL_ERROR ((void*)cancel_error) // 'cancel_error' sentinel static int cancel_error( lua_State* L) { STACK_GROW( L, 1); lua_pushlightuserdata( L, CANCEL_ERROR); // special error value return lua_error( L); // doesn't return } static void cancel_hook( lua_State* L, lua_Debug* ar) { (void)ar; if( cancel_test( L) != CANCEL_NONE) { cancel_error( L); } } #if ERROR_FULL_STACK static int lane_error( lua_State* L); #define STACK_TRACE_KEY ((void*)lane_error) // used as registry key #endif // ERROR_FULL_STACK /* * registry[FINALIZER_REG_KEY] is either nil (no finalizers) or a table * of functions that Lanes will call after the executing 'pcall' has ended. * * We're NOT using the GC system for finalizer mainly because providing the * error (and maybe stack trace) parameters to the finalizer functions would * anyways complicate that approach. */ #define FINALIZER_REG_KEY ((void*)LG_set_finalizer) struct s_Linda; #if 1 # define DEBUG_SIGNAL( msg, signal_ref ) /* */ #else # define DEBUG_SIGNAL( msg, signal_ref ) \ { int i; unsigned char *ptr; char buf[999]; \ sprintf( buf, ">>> " msg ": %p\t", (signal_ref) ); \ ptr= (unsigned char *)signal_ref; \ for( i=0; i ... -> ... -> (-1)' #define TRACKING_END ((struct s_lane *)(-1)) /* * Add the lane to tracking chain; the ones still running at the end of the * whole process will be cancelled. */ static void tracking_add( struct s_lane* s) { MUTEX_LOCK( &tracking_cs); { assert( s->tracking_next == NULL); s->tracking_next = tracking_first; tracking_first = s; } MUTEX_UNLOCK( &tracking_cs); } /* * A free-running lane has ended; remove it from tracking chain */ static bool_t tracking_remove( struct s_lane* s) { bool_t found = FALSE; MUTEX_LOCK( &tracking_cs); { // Make sure (within the MUTEX) that we actually are in the chain // still (at process exit they will remove us from chain and then // cancel/kill). // if (s->tracking_next != NULL) { struct s_lane** ref= (struct s_lane**) &tracking_first; while( *ref != TRACKING_END) { if( *ref == s) { *ref = s->tracking_next; s->tracking_next = NULL; found = TRUE; break; } ref = (struct s_lane**) &((*ref)->tracking_next); } assert( found); } } MUTEX_UNLOCK( &tracking_cs); return found; } #endif // HAVE_LANE_TRACKING //--- // low-level cleanup static void lane_cleanup( struct s_lane* s) { // Clean up after a (finished) thread // #if THREADWAIT_METHOD == THREADWAIT_CONDVAR SIGNAL_FREE( &s->done_signal); MUTEX_FREE( &s->done_lock); #endif // THREADWAIT_METHOD == THREADWAIT_CONDVAR #if HAVE_LANE_TRACKING if( tracking_first != NULL) { // Lane was cleaned up, no need to handle at process termination tracking_remove( s); } #endif // HAVE_LANE_TRACKING free( s); } /* * ############################################################################################### * ############################################ Linda ############################################ * ############################################################################################### */ /* * Actual data is kept within a keeper state, which is hashed by the 's_Linda' * pointer (which is same to all userdatas pointing to it). */ struct s_Linda { SIGNAL_T read_happened; SIGNAL_T write_happened; char name[1]; }; static void linda_id( lua_State*, char const * const which); #define lua_toLinda(L,n) ((struct s_Linda *)luaG_todeep( L, linda_id, n )) static void check_key_types( lua_State*L, int _start, int _end) { int i; for( i = _start; i <= _end; ++ i) { int t = lua_type( L, i); if( t == LUA_TBOOLEAN || t == LUA_TNUMBER || t == LUA_TSTRING || t == LUA_TLIGHTUSERDATA) { continue; } (void) luaL_error( L, "argument #%d: invalid key type (not a boolean, string, number or light userdata)", i); } } /* * bool= linda_send( linda_ud, [timeout_secs=-1,] key_num|str|bool|lightuserdata, ... ) * * Send one or more values to a Linda. If there is a limit, all values must fit. * * Returns: 'true' if the value was queued * 'false' for timeout (only happens when the queue size is limited) * nil, CANCEL_ERROR if cancelled */ LUAG_FUNC( linda_send) { struct s_Linda *linda = lua_toLinda( L, 1); bool_t ret; enum e_cancel_request cancel = CANCEL_NONE; int pushed; time_d timeout= -1.0; uint_t key_i = 2; // index of first key, if timeout not there luaL_argcheck( L, linda, 1, "expected a linda object!"); if( lua_type( L, 2) == LUA_TNUMBER) // we don't want to use lua_isnumber() because of autocoercion { timeout = SIGNAL_TIMEOUT_PREPARE( lua_tonumber( L,2)); ++ key_i; } else if( lua_isnil( L, 2)) // alternate explicit "no timeout" by passing nil before the key { ++ key_i; } // make sure the keys are of a valid type check_key_types( L, key_i, key_i); // make sure there is something to send if( (uint_t)lua_gettop( L) == key_i) { return luaL_error( L, "no data to send"); } // convert nils to some special non-nil sentinel in sent values keeper_toggle_nil_sentinels( L, key_i + 1, eLM_ToKeeper); STACK_GROW( L, 1); { struct s_Keeper* K = keeper_acquire( linda); lua_State* KL = K ? K->L : NULL; // need to do this for 'STACK_CHECK' if( KL == NULL) return 0; STACK_CHECK( KL); for( ;;) { STACK_MID( KL, 0); pushed = keeper_call( KL, KEEPER_API( send), L, linda, key_i); if( pushed < 0) { ret = FALSE; break; } ASSERT_L( pushed == 1); ret = lua_toboolean( L, -1); lua_pop( L, 1); if( ret) { // Wake up ALL waiting threads // SIGNAL_ALL( &linda->write_happened); break; } if( timeout == 0.0) { break; /* no wait; instant timeout */ } /* limit faced; push until timeout */ { enum e_status prev_status = ERROR_ST; // prevent 'might be used uninitialized' warnings struct s_lane* const s = get_lane_from_registry( L); if( s != NULL) { cancel = s->cancel_request; // testing here causes no delays if( cancel != CANCEL_NONE) // if user wants to cancel, the call returns without sending anything { break; } // change status of lane to "waiting" prev_status = s->status; // RUNNING, most likely ASSERT_L( prev_status == RUNNING); // but check, just in case s->status = WAITING; ASSERT_L( s->waiting_on == NULL); s->waiting_on = &linda->read_happened; } // could not send because no room: wait until some data was read before trying again, or until timeout is reached if( !SIGNAL_WAIT( &linda->read_happened, &K->lock_, timeout)) { if( s != NULL) { s->waiting_on = NULL; s->status = prev_status; // if woken by a cancel request, be sure to handle it properly cancel = s->cancel_request; } break; } if( s != NULL) { s->waiting_on = NULL; s->status = prev_status; } } } STACK_END( KL, 0); keeper_release( K); } // must trigger error after keeper state has been released if( pushed < 0) { return luaL_error( L, "tried to copy unsupported types"); } switch( cancel) { case CANCEL_SOFT: // if user wants to soft-cancel, the call returns CANCEL_ERROR lua_pushlightuserdata( L, CANCEL_ERROR); return 1; case CANCEL_HARD: // raise an error interrupting execution only in case of hard cancel return cancel_error( L); // raises an error and doesn't return default: lua_pushboolean( L, ret); // true (success) or false (timeout) return 1; } } /* * 2 modes of operation * [val, key]= linda_receive( linda_ud, [timeout_secs_num=-1], key_num|str|bool|lightuserdata [, ...] ) * Consumes a single value from the Linda, in any key. * Returns: received value (which is consumed from the slot), and the key which had it * [val1, ... valCOUNT]= linda_receive( linda_ud, [timeout_secs_num=-1], linda.batched, key_num|str|bool|lightuserdata, min_COUNT[, max_COUNT]) * Consumes between min_COUNT and max_COUNT values from the linda, from a single key. * returns the actual consumed values, or nil if there weren't enough values to consume * */ #define BATCH_SENTINEL "270e6c9d-280f-4983-8fee-a7ecdda01475" LUAG_FUNC( linda_receive) { struct s_Linda *linda = lua_toLinda( L, 1); int pushed, expected_pushed_min, expected_pushed_max; enum e_cancel_request cancel = CANCEL_NONE; keeper_api_t keeper_receive; time_d timeout = -1.0; uint_t key_i = 2; luaL_argcheck( L, linda, 1, "expected a linda object!"); if( lua_type( L, 2) == LUA_TNUMBER) // we don't want to use lua_isnumber() because of autocoercion { timeout = SIGNAL_TIMEOUT_PREPARE( lua_tonumber( L, 2)); ++ key_i; } else if( lua_isnil( L, 2)) // alternate explicit "no timeout" by passing nil before the key { ++ key_i; } // are we in batched mode? { int is_batched; lua_pushliteral( L, BATCH_SENTINEL); is_batched = lua_equal( L, key_i, -1); lua_pop( L, 1); if( is_batched) { // no need to pass linda.batched in the keeper state ++ key_i; // make sure the keys are of a valid type check_key_types( L, key_i, key_i); // receive multiple values from a single slot keeper_receive = KEEPER_API( receive_batched); // we expect a user-defined amount of return value expected_pushed_min = (int)luaL_checkinteger( L, key_i + 1); expected_pushed_max = (int)luaL_optinteger( L, key_i + 2, expected_pushed_min); // don't forget to count the key in addition to the values ++ expected_pushed_min; ++ expected_pushed_max; if( expected_pushed_min > expected_pushed_max) { return luaL_error( L, "batched min/max error"); } } else { // make sure the keys are of a valid type check_key_types( L, key_i, lua_gettop( L)); // receive a single value, checking multiple slots keeper_receive = KEEPER_API( receive); // we expect a single (value, key) pair of returned values expected_pushed_min = expected_pushed_max = 2; } } { struct s_Keeper *K = keeper_acquire( linda); if( K == NULL) return 0; for( ;;) { // all arguments of receive() but the first are passed to the keeper's receive function pushed = keeper_call( K->L, keeper_receive, L, linda, key_i); if( pushed < 0) { break; } if( pushed > 0) { ASSERT_L( pushed >= expected_pushed_min && pushed <= expected_pushed_max); // replace sentinels with real nils keeper_toggle_nil_sentinels( L, lua_gettop( L) - pushed, eLM_FromKeeper); // To be done from within the 'K' locking area // SIGNAL_ALL( &linda->read_happened); break; } if( timeout == 0.0) { break; /* instant timeout */ } /* nothing received; wait until timeout */ { enum e_status prev_status = ERROR_ST; // prevent 'might be used uninitialized' warnings struct s_lane* const s = get_lane_from_registry( L); if( s != NULL) { cancel = s->cancel_request; // testing here causes no delays if( cancel != CANCEL_NONE) // if user wants to cancel, the call returns without providing anything { break; } // change status of lane to "waiting" prev_status = s->status; // RUNNING, most likely ASSERT_L( prev_status == RUNNING); // but check, just in case s->status = WAITING; ASSERT_L( s->waiting_on == NULL); s->waiting_on = &linda->write_happened; } // not enough data to read: wakeup when data was sent, or when timeout is reached if( !SIGNAL_WAIT( &linda->write_happened, &K->lock_, timeout)) { if( s != NULL) { s->waiting_on = NULL; s->status = prev_status; // if woken by a cancel request, be sure to handle it properly cancel = s->cancel_request; } break; } if( s != NULL) { s->waiting_on = NULL; s->status = prev_status; } } } keeper_release( K); } // must trigger error after keeper state has been released if( pushed < 0) { return luaL_error( L, "tried to copy unsupported types"); } switch( cancel) { case CANCEL_SOFT: // if user wants to soft-cancel, the call returns CANCEL_ERROR lua_pushlightuserdata( L, CANCEL_ERROR); return 1; case CANCEL_HARD: // raise an error interrupting execution only in case of hard cancel return cancel_error( L); // raises an error and doesn't return default: return pushed; } } /* * [true] = linda_set( linda_ud, key_num|str|bool|lightuserdata [, value [, ...]]) * * Set one or more value to Linda. * TODO: what do we do if we set to non-nil and limit is 0? * * Existing slot value is replaced, and possible queued entries removed. */ LUAG_FUNC( linda_set) { struct s_Linda* const linda = lua_toLinda( L, 1); int pushed; bool_t has_value = lua_gettop( L) > 2; luaL_argcheck( L, linda, 1, "expected a linda object!"); // make sure the key is of a valid type (throws an error if not the case) check_key_types( L, 2, 2); { struct s_Keeper* K = keeper_acquire( linda); if( K == NULL) return 0; if( has_value) { // convert nils to some special non-nil sentinel in sent values keeper_toggle_nil_sentinels( L, 3, eLM_ToKeeper); } pushed = keeper_call( K->L, KEEPER_API( set), L, linda, 2); if( pushed >= 0) // no error? { ASSERT_L( pushed == 0 || pushed == 1); if( has_value) { // we put some data in the slot, tell readers that they should wake SIGNAL_ALL( &linda->write_happened); // To be done from within the 'K' locking area } if( pushed == 1) { // the key was full, but it is no longer the case, tell writers they should wake ASSERT_L( lua_type( L, -1) == LUA_TBOOLEAN && lua_toboolean( L, -1) == 1); SIGNAL_ALL( &linda->read_happened); // To be done from within the 'K' locking area } } keeper_release( K); } // must trigger any error after keeper state has been released return (pushed < 0) ? luaL_error( L, "tried to copy unsupported types") : pushed; } /* * [val] = linda_count( linda_ud, [key [, ...]]) * * Get a count of the pending elements in the specified keys */ LUAG_FUNC( linda_count) { struct s_Linda* linda = lua_toLinda( L, 1); int pushed; luaL_argcheck( L, linda, 1, "expected a linda object!"); // make sure the keys are of a valid type check_key_types( L, 2, lua_gettop( L)); { struct s_Keeper* K = keeper_acquire( linda); if( K == NULL) return 0; pushed = keeper_call( K->L, KEEPER_API( count), L, linda, 2); keeper_release( K); if( pushed < 0) { return luaL_error( L, "tried to count an invalid key"); } } return pushed; } /* * [val [, ...]] = linda_get( linda_ud, key_num|str|bool|lightuserdata [, count = 1]) * * Get one or more values from Linda. */ LUAG_FUNC( linda_get) { struct s_Linda* const linda = lua_toLinda( L, 1); int pushed; int count = luaL_optint( L, 3, 1); luaL_argcheck( L, count >= 1, 3, "count should be >= 1"); luaL_argcheck( L, linda, 1, "expected a linda object"); luaL_argcheck( L, lua_gettop( L) <= 3, 4, "too many arguments"); // make sure the key is of a valid type (throws an error if not the case) check_key_types( L, 2, 2); { struct s_Keeper* K = keeper_acquire( linda); if( K == NULL) return 0; pushed = keeper_call( K->L, KEEPER_API( get), L, linda, 2); if( pushed > 0) { keeper_toggle_nil_sentinels( L, lua_gettop( L) - pushed, eLM_FromKeeper); } keeper_release( K); // must trigger error after keeper state has been released // (an error can be raised if we attempt to read an unregistered function) if( pushed < 0) { return luaL_error( L, "tried to copy unsupported types"); } } return pushed; } /* * [true] = linda_limit( linda_ud, key_num|str|bool|lightuserdata, int) * * Set limit to 1 Linda keys. * Optionally wake threads waiting to write on the linda, in case the limit enables them to do so */ LUAG_FUNC( linda_limit) { struct s_Linda* linda = lua_toLinda( L, 1); int pushed; bool_t wake_writers = FALSE; // make sure we got 3 arguments: the linda, a key and a limit luaL_argcheck( L, linda, 1, "expected a linda object!"); luaL_argcheck( L, lua_gettop( L) == 3, 2, "wrong number of arguments"); // make sure we got a numeric limit luaL_checknumber( L, 3); // make sure the key is of a valid type check_key_types( L, 2, 2); { struct s_Keeper* K = keeper_acquire( linda); if( K == NULL) return 0; pushed = keeper_call( K->L, KEEPER_API( limit), L, linda, 2); ASSERT_L( pushed == 0 || pushed == 1); // no error, optional boolean value saying if we should wake blocked writer threads if( pushed == 1) { ASSERT_L( lua_type( L, -1) == LUA_TBOOLEAN && lua_toboolean( L, -1) == 1); SIGNAL_ALL( &linda->read_happened); // To be done from within the 'K' locking area } keeper_release( K); } // propagate pushed boolean if any return pushed; } /* * lightuserdata= linda_deep( linda_ud ) * * Return the 'deep' userdata pointer, identifying the Linda. * * This is needed for using Lindas as key indices (timer system needs it); * separately created proxies of the same underlying deep object will have * different userdata and won't be known to be essentially the same deep one * without this. */ LUAG_FUNC( linda_deep ) { struct s_Linda *linda= lua_toLinda( L, 1 ); luaL_argcheck( L, linda, 1, "expected a linda object!"); lua_pushlightuserdata( L, linda ); // just the address return 1; } /* * string = linda:__tostring( linda_ud) * * Return the stringification of a linda * * Useful for concatenation or debugging purposes */ static int linda_tostring( lua_State* L, int _idx, bool_t _opt) { struct s_Linda* linda = lua_toLinda( L, _idx); if( !_opt) { luaL_argcheck( L, linda, _idx, "expected a linda object!"); } if( linda != NULL) { char text[32]; int len; if( linda->name[0]) len = sprintf( text, "Linda: %.*s", (int)sizeof(text) - 8, linda->name); else len = sprintf( text, "Linda: %p", linda); lua_pushlstring( L, text, len); return 1; } return 0; } LUAG_FUNC( linda_tostring) { return linda_tostring( L, 1, FALSE); } /* * string = linda:__concat( a, b) * * Return the concatenation of a pair of items, one of them being a linda * * Useful for concatenation or debugging purposes */ LUAG_FUNC( linda_concat) { // linda1? linda2? bool_t atLeastOneLinda = FALSE; // Lua semantics enforce that one of the 2 arguments is a Linda, but not necessarily both. if( linda_tostring( L, 1, TRUE)) { atLeastOneLinda = TRUE; lua_replace( L, 1); } if( linda_tostring( L, 2, TRUE)) { atLeastOneLinda = TRUE; lua_replace( L, 2); } if( !atLeastOneLinda) // should not be possible { return luaL_error( L, "internal error: linda_concat called on non-Linda"); } lua_concat( L, 2); return 1; } /* * table = linda:dump() * return a table listing all pending data inside the linda */ LUAG_FUNC( linda_dump) { struct s_Linda* linda = lua_toLinda( L, 1); return keeper_push_linda_storage( L, linda); } /* * Identity function of a shared userdata object. * * lightuserdata= linda_id( "new" [, ...] ) * = linda_id( "delete", lightuserdata ) * * Creation and cleanup of actual 'deep' objects. 'luaG_...' will wrap them into * regular userdata proxies, per each state using the deep data. * * tbl= linda_id( "metatable" ) * * Returns a metatable for the proxy objects ('__gc' method not needed; will * be added by 'luaG_...') * * string= linda_id( "module") * * Returns the name of the module that a state should require * in order to keep a handle on the shared library that exported the idfunc * * = linda_id( str, ... ) * * For any other strings, the ID function must not react at all. This allows * future extensions of the system. */ static void linda_id( lua_State*L, char const * const which) { if (strcmp( which, "new" )==0) { struct s_Linda *s; size_t name_len = 0; char const* linda_name = NULL; int const top = lua_gettop( L); if( top > 0 && lua_type( L, top) == LUA_TSTRING) { linda_name = lua_tostring( L, top); name_len = strlen( linda_name); } /* The deep data is allocated separately of Lua stack; we might no * longer be around when last reference to it is being released. * One can use any memory allocation scheme. */ s= (struct s_Linda *) malloc( sizeof(struct s_Linda) + name_len); // terminating 0 is already included ASSERT_L(s); SIGNAL_INIT( &s->read_happened ); SIGNAL_INIT( &s->write_happened ); s->name[0] = 0; memcpy( s->name, linda_name, name_len ? name_len + 1 : 0); lua_pushlightuserdata( L, s ); } else if( strcmp( which, "delete" ) == 0) { struct s_Keeper* K; struct s_Linda* l= lua_touserdata( L, 1); ASSERT_L( l); /* Clean associated structures in the keeper state. */ K = keeper_acquire( l); if( K && K->L) // can be NULL if this happens during main state shutdown (lanes is GC'ed -> no keepers -> no need to cleanup) { keeper_call( K->L, KEEPER_API( clear), L, l, 0); } keeper_release( K); /* There aren't any lanes waiting on these lindas, since all proxies * have been gc'ed. Right? */ SIGNAL_FREE( &l->read_happened); SIGNAL_FREE( &l->write_happened); free( l); } else if (strcmp( which, "metatable" )==0) { STACK_CHECK( L); lua_newtable(L); // metatable is its own index lua_pushvalue( L, -1); lua_setfield( L, -2, "__index"); // protect metatable from external access lua_pushliteral( L, "Linda"); lua_setfield( L, -2, "__metatable"); lua_pushcfunction( L, LG_linda_tostring); lua_setfield( L, -2, "__tostring"); // Decoda __towatch support lua_pushcfunction( L, LG_linda_dump); lua_setfield( L, -2, "__towatch"); lua_pushcfunction( L, LG_linda_concat); lua_setfield( L, -2, "__concat"); // // [-1]: linda metatable lua_pushcfunction( L, LG_linda_send ); lua_setfield( L, -2, "send" ); lua_pushcfunction( L, LG_linda_receive ); lua_setfield( L, -2, "receive" ); lua_pushcfunction( L, LG_linda_limit ); lua_setfield( L, -2, "limit" ); lua_pushcfunction( L, LG_linda_set ); lua_setfield( L, -2, "set" ); lua_pushcfunction( L, LG_linda_count ); lua_setfield( L, -2, "count" ); lua_pushcfunction( L, LG_linda_get ); lua_setfield( L, -2, "get" ); lua_pushcfunction( L, LG_linda_deep ); lua_setfield( L, -2, "deep" ); lua_pushcfunction( L, LG_linda_dump); lua_setfield( L, -2, "dump" ); lua_pushliteral( L, BATCH_SENTINEL); lua_setfield(L, -2, "batched"); STACK_END( L, 1); } else if( strcmp( which, "module") == 0) { // linda is a special case because we know lanes must be loaded from the main lua state // to be able to ever get here, so we know it will remain loaded as long a the main state is around // in other words, forever. lua_pushnil( L); // other idfuncs must push a string naming the module they come from //lua_pushliteral( L, "lanes.core"); } } /* * ud = lanes.linda() * * returns a linda object */ LUAG_FUNC( linda) { int const top = lua_gettop( L); luaL_argcheck( L, top <= 1, top, "too many arguments"); if( top == 1) luaL_checktype( L, 1, LUA_TSTRING); return luaG_deep_userdata( L, linda_id); } /* * ############################################################################################### * ########################################## Finalizer ########################################## * ############################################################################################### */ //--- // void= finalizer( finalizer_func ) // // finalizer_func( [err, stack_tbl] ) // // Add a function that will be called when exiting the lane, either via // normal return or an error. // LUAG_FUNC( set_finalizer ) { STACK_GROW(L,3); // Get the current finalizer table (if any) // push_registry_table( L, FINALIZER_REG_KEY, TRUE /*do create if none*/ ); lua_pushinteger( L, lua_rawlen(L,-1)+1 ); lua_pushvalue( L, 1 ); // copy of the function lua_settable( L, -3 ); lua_pop(L,1); return 0; } //--- // Run finalizers - if any - with the given parameters // // If 'rc' is nonzero, error message and stack index (the latter only when ERROR_FULL_STACK == 1) are available as: // [-1]: stack trace (table) // [-2]: error message (any type) // // Returns: // 0 if finalizers were run without error (or there were none) // LUA_ERRxxx return code if any of the finalizers failed // // TBD: should we add stack trace on failing finalizer, wouldn't be hard.. // static int run_finalizers( lua_State* L, int lua_rc) { int error_index, finalizers_index; int n; int err_handler_index = 0; int rc = 0; // [err_msg {stack_trace}]? if( !push_registry_table( L, FINALIZER_REG_KEY, FALSE)) // [err_msg {stack_trace}]? {func [, ...]}? { return 0; // no finalizers } STACK_GROW( L, 5); finalizers_index = lua_gettop( L); #if ERROR_FULL_STACK lua_pushcfunction( L, lane_error); // [err_msg {stack_trace}]? {func [, ...]}? lane_error err_handler_index = lua_gettop( L); #endif // ERROR_FULL_STACK error_index = (lua_rc != LUA_OK) ? finalizers_index - (1 + ERROR_FULL_STACK) : 0; for( n = (int) lua_rawlen( L, finalizers_index); n > 0; -- n) { int args = 0; lua_pushinteger( L, n); // [err_msg {stack_trace}]? {func [, ...]}? lane_error n lua_gettable( L, finalizers_index); // [err_msg {stack_trace}]? {func [, ...]}? lane_error finalizer ASSERT_L( lua_isfunction( L, -1)); if( error_index) { //char const* err_msg = lua_tostring( L, error_index); lua_pushvalue( L, error_index); // [err_msg {stack_trace}]? {func [, ...]}? lane_error finalizer err_msg #if ERROR_FULL_STACK lua_pushvalue( L, error_index + 1); // [err_msg {stack_trace}]? {func [, ...]}? lane_error finalizer err_msg {stack_trace} #endif // ERROR_FULL_STACK args = 1 + ERROR_FULL_STACK; } rc = lua_pcall( L, args, 0, err_handler_index); // [err_msg {stack_trace}]? {func [, ...]}? lane_error err_msg2? // // LUA_ERRRUN / LUA_ERRMEM if( rc != LUA_OK) { #if ERROR_FULL_STACK lua_pushlightuserdata( L, STACK_TRACE_KEY); // [err_msg {stack_trace}]? {func [, ...]}? lane_error err_msg2 STACK_TRACE_KEY lua_gettable( L, LUA_REGISTRYINDEX); // [err_msg {stack_trace}]? {func [, ...]}? lane_error err_msg2 {stack_trace2} #endif // ERROR_FULL_STACK // If one finalizer fails, don't run the others. Return this // as the 'real' error, replacing what we could have had (or not) // from the actual code. // break; } } // remove error handler function (if any) and finalizers table from the stack #if ERROR_FULL_STACK lua_remove( L, err_handler_index); // [err_msg {stack_trace}]? {func [, ...]}? err_msg2 {stack_trace2} #endif // ERROR_FULL_STACK lua_remove( L, finalizers_index); // [err_msg {stack_trace}]? err_msg2 {stack_trace2} return rc; } /* * ############################################################################################### * ########################################### Threads ########################################### * ############################################################################################### */ //--- // = thread_cancel( lane_ud [,timeout_secs=0.0] [,force_kill_bool=false] ) // // The originator thread asking us specifically to cancel the other thread. // // 'timeout': <0: wait forever, until the lane is finished // 0.0: just signal it to cancel, no time waited // >0: time to wait for the lane to detect cancellation // // 'force_kill': if true, and lane does not detect cancellation within timeout, // it is forcefully killed. Using this with 0.0 timeout means just kill // (unless the lane is already finished). // // Returns: true if the lane was already finished (DONE/ERROR_ST/CANCELLED) or if we // managed to cancel it. // false if the cancellation timed out, or a kill was needed. // typedef enum { CR_Timeout, CR_Cancelled, CR_Killed } cancel_result; static cancel_result thread_cancel( lua_State* L, struct s_lane* s, double secs, bool_t force, double waitkill_timeout_) { cancel_result result; // remember that lanes are not transferable: only one thread can cancel a lane, so no multithreading issue here // We can read 's->status' without locks, but not wait for it (if Posix no PTHREAD_TIMEDJOIN) if( s->mstatus == KILLED) { result = CR_Killed; } else if( s->status < DONE) { // signal the linda the wake up the thread so that it can react to the cancel query // let us hope we never land here with a pointer on a linda that has been destroyed... if( secs < 0.0) { s->cancel_request = CANCEL_SOFT; // it's now signaled to stop // negative timeout: we don't want to truly abort the lane, we just want it to react to cancel_test() on its own if( force) // wake the thread so that execution returns from any pending linda operation if desired { SIGNAL_T *waiting_on = s->waiting_on; if( s->status == WAITING && waiting_on != NULL) { SIGNAL_ALL( waiting_on); } } // say we succeeded though result = CR_Cancelled; } else { s->cancel_request = CANCEL_HARD; // it's now signaled to stop { SIGNAL_T *waiting_on = s->waiting_on; if( s->status == WAITING && waiting_on != NULL) { SIGNAL_ALL( waiting_on); } } result = THREAD_WAIT( &s->thread, secs, &s->done_signal, &s->done_lock, &s->status) ? CR_Cancelled : CR_Timeout; if( (result == CR_Timeout) && force) { // Killing is asynchronous; we _will_ wait for it to be done at // GC, to make sure the data structure can be released (alternative // would be use of "cancellation cleanup handlers" that at least // PThread seems to have). // THREAD_KILL( &s->thread); #if THREADAPI == THREADAPI_PTHREAD // pthread: make sure the thread is really stopped! // note that this may block forever if the lane doesn't call a cancellation point and pthread doesn't honor PTHREAD_CANCEL_ASYNCHRONOUS result = THREAD_WAIT( &s->thread, waitkill_timeout_, &s->done_signal, &s->done_lock, &s->status); if( result == CR_Timeout) { return luaL_error( L, "force-killed lane failed to terminate within %f second%s", waitkill_timeout_, waitkill_timeout_ > 1 ? "s" : ""); } #endif // THREADAPI == THREADAPI_PTHREAD s->mstatus = KILLED; // mark 'gc' to wait for it // note that s->status value must remain to whatever it was at the time of the kill // because we need to know if we can lua_close() the Lua State or not. result = CR_Killed; } } } else { // say "ok" by default, including when lane is already done result = CR_Cancelled; } return result; } static MUTEX_T selfdestruct_cs; // // Protects modifying the selfdestruct chain #define SELFDESTRUCT_END ((struct s_lane*)(-1)) // // The chain is ended by '(struct s_lane*)(-1)', not NULL: // 'selfdestruct_first -> ... -> ... -> (-1)' struct s_lane* volatile selfdestruct_first = SELFDESTRUCT_END; // After a lane has removed itself from the chain, it still performs some processing. // The terminal desinit sequence should wait for all such processing to terminate before force-killing threads int volatile selfdestructing_count = 0; /* * Add the lane to selfdestruct chain; the ones still running at the end of the * whole process will be cancelled. */ static void selfdestruct_add( struct s_lane* s) { MUTEX_LOCK( &selfdestruct_cs ); { assert( s->selfdestruct_next == NULL ); s->selfdestruct_next= selfdestruct_first; selfdestruct_first= s; } MUTEX_UNLOCK( &selfdestruct_cs ); } /* * A free-running lane has ended; remove it from selfdestruct chain */ static bool_t selfdestruct_remove( struct s_lane* s) { bool_t found = FALSE; MUTEX_LOCK( &selfdestruct_cs ); { // Make sure (within the MUTEX) that we actually are in the chain // still (at process exit they will remove us from chain and then // cancel/kill). // if (s->selfdestruct_next != NULL) { struct s_lane** ref= (struct s_lane**) &selfdestruct_first; while( *ref != SELFDESTRUCT_END ) { if (*ref == s) { *ref= s->selfdestruct_next; s->selfdestruct_next= NULL; // the terminal shutdown should wait until the lane is done with its lua_close() ++ selfdestructing_count; found= TRUE; break; } ref= (struct s_lane**) &((*ref)->selfdestruct_next); } assert( found ); } } MUTEX_UNLOCK( &selfdestruct_cs ); return found; } // Initialized by 'init_once_LOCKED()': the deep userdata Linda object // used for timers (each lane will get a proxy to this) // volatile DEEP_PRELUDE* timer_deep; // = NULL /* ** mutex-protected allocator for use with Lua states that have non-threadsafe allocators (such as LuaJIT) */ struct ProtectedAllocator_s { lua_Alloc allocf; void* ud; MUTEX_T lock; }; void * protected_lua_Alloc( void *ud, void *ptr, size_t osize, size_t nsize) { void* p; struct ProtectedAllocator_s* s = (struct ProtectedAllocator_s*) ud; MUTEX_LOCK( &s->lock); p = s->allocf( s->ud, ptr, osize, nsize); MUTEX_UNLOCK( &s->lock); return p; } /* * Process end; cancel any still free-running threads */ static int selfdestruct_gc( lua_State* L) { while( selfdestruct_first != SELFDESTRUCT_END) // true at most once! { // Signal _all_ still running threads to exit (including the timer thread) // MUTEX_LOCK( &selfdestruct_cs); { struct s_lane* s = selfdestruct_first; while( s != SELFDESTRUCT_END) { // attempt a regular unforced hard cancel with a small timeout bool_t cancelled = THREAD_ISNULL( s->thread) || thread_cancel( L, s, 0.0001, FALSE, 0.0); // if we failed, and we know the thread is waiting on a linda if( cancelled == FALSE && s->status == WAITING && s->waiting_on != NULL) { // signal the linda the wake up the thread so that it can react to the cancel query // let us hope we never land here with a pointer on a linda that has been destroyed... SIGNAL_T *waiting_on = s->waiting_on; //s->waiting_on = NULL; // useful, or not? SIGNAL_ALL( waiting_on); } s = s->selfdestruct_next; } } MUTEX_UNLOCK( &selfdestruct_cs); // When noticing their cancel, the lanes will remove themselves from // the selfdestruct chain. // TBD: Not sure if Windows (multi core) will require the timed approach, // or single Yield. I don't have machine to test that (so leaving // for timed approach). -- AKa 25-Oct-2008 // OS X 10.5 (Intel) needs more to avoid segfaults. // // "make test" is okay. 100's of "make require" are okay. // // Tested on MacBook Core Duo 2GHz and 10.5.5: // -- AKa 25-Oct-2008 // { lua_Number const shutdown_timeout = lua_tonumber( L, lua_upvalueindex( 1)); double const t_until = now_secs() + shutdown_timeout; while( selfdestruct_first != SELFDESTRUCT_END) { YIELD(); // give threads time to act on their cancel { // count the number of cancelled thread that didn't have the time to act yet int n = 0; double t_now = 0.0; MUTEX_LOCK( &selfdestruct_cs); { struct s_lane* s = selfdestruct_first; while( s != SELFDESTRUCT_END) { if( s->cancel_request == CANCEL_HARD) ++ n; s = s->selfdestruct_next; } } MUTEX_UNLOCK( &selfdestruct_cs); // if timeout elapsed, or we know all threads have acted, stop waiting t_now = now_secs(); if( n == 0 || (t_now >= t_until)) { DEBUGSPEW_CODE( fprintf( stderr, "%d uncancelled lane(s) remain after waiting %fs at process end.\n", n, shutdown_timeout - (t_until - t_now))); break; } } } } // If some lanes are currently cleaning after themselves, wait until they are done. // They are no longer listed in the selfdestruct chain, but they still have to lua_close(). { bool_t again = TRUE; do { MUTEX_LOCK( &selfdestruct_cs); again = (selfdestructing_count > 0) ? TRUE : FALSE; MUTEX_UNLOCK( &selfdestruct_cs); YIELD(); } while( again); } //--- // Kill the still free running threads // if( selfdestruct_first != SELFDESTRUCT_END) { unsigned int n = 0; // first thing we did was to raise the linda signals the threads were waiting on (if any) // therefore, any well-behaved thread should be in CANCELLED state // these are not running, and the state can be closed MUTEX_LOCK( &selfdestruct_cs); { struct s_lane* s = selfdestruct_first; while( s != SELFDESTRUCT_END) { struct s_lane* next_s = s->selfdestruct_next; s->selfdestruct_next = NULL; // detach from selfdestruct chain if( !THREAD_ISNULL( s->thread)) // can be NULL if previous 'soft' termination succeeded { THREAD_KILL( &s->thread); #if THREADAPI == THREADAPI_PTHREAD // pthread: make sure the thread is really stopped! THREAD_WAIT( &s->thread, -1, &s->done_signal, &s->done_lock, &s->status); #endif // THREADAPI == THREADAPI_PTHREAD } // NO lua_close() in this case because we don't know where execution of the state was interrupted lane_cleanup( s); s = next_s; ++ n; } selfdestruct_first = SELFDESTRUCT_END; } MUTEX_UNLOCK( &selfdestruct_cs); DEBUGSPEW_CODE( fprintf( stderr, "Killed %d lane(s) at process end.\n", n)); } } #if !HAVE_KEEPER_ATEXIT_DESINIT close_keepers(); #endif // !HAVE_KEEPER_ATEXIT_DESINIT // remove the protected allocator, if any { void* ud; lua_Alloc allocf = lua_getallocf( L, &ud); if( allocf == protected_lua_Alloc) { struct ProtectedAllocator_s* s = (struct ProtectedAllocator_s*) ud; lua_setallocf( L, s->allocf, s->ud); MUTEX_FREE( &s->lock); s->allocf( s->ud, s, sizeof( struct ProtectedAllocator_s), 0); } } return 0; } //--- // bool = cancel_test() // // Available inside the global namespace of lanes // returns a boolean saying if a cancel request is pending // LUAG_FUNC( cancel_test) { enum e_cancel_request test = cancel_test( L); lua_pushboolean( L, test != CANCEL_NONE); return 1; } //--- // = _single( [cores_uint=1] ) // // Limits the process to use only 'cores' CPU cores. To be used for performance // testing on multicore devices. DEBUGGING ONLY! // LUAG_FUNC( set_singlethreaded) { uint_t cores = luaG_optunsigned( L, 1, 1); (void) cores; // prevent "unused" warning #ifdef PLATFORM_OSX #ifdef _UTILBINDTHREADTOCPU if( cores > 1) { return luaL_error( L, "Limiting to N>1 cores not possible"); } // requires 'chudInitialize()' utilBindThreadToCPU(0); // # of CPU to run on (we cannot limit to 2..N CPUs?) #else return luaL_error( L, "Not available: compile with _UTILBINDTHREADTOCPU"); #endif #else return luaL_error( L, "not implemented"); #endif return 0; } /* * str= lane_error( error_val|str ) * * Called if there's an error in some lane; add call stack to error message * just like 'lua.c' normally does. * * ".. will be called with the error message and its return value will be the * message returned on the stack by lua_pcall." * * Note: Rather than modifying the error message itself, it would be better * to provide the call stack (as string) completely separated. This would * work great with non-string error values as well (current system does not). * (This is NOT possible with the Lua 5.1 'lua_pcall()'; we could of course * implement a Lanes-specific 'pcall' of our own that does this). TBD!!! :) * --AKa 22-Jan-2009 */ #if ERROR_FULL_STACK # define EXTENDED_STACK_TRACE_KEY ((void*)LG_set_error_reporting) // used as registry key LUAG_FUNC( set_error_reporting) { bool_t equal; luaL_checktype( L, 1, LUA_TSTRING); lua_pushliteral( L, "extended"); equal = lua_rawequal( L, -1, 1); lua_pop( L, 1); if( equal) { goto done; } lua_pushliteral( L, "basic"); equal = !lua_rawequal( L, -1, 1); lua_pop( L, 1); if( equal) { return luaL_error( L, "unsupported error reporting model"); } done: lua_pushlightuserdata( L, EXTENDED_STACK_TRACE_KEY); lua_pushboolean( L, equal); lua_rawset( L, LUA_REGISTRYINDEX); return 0; } static int lane_error( lua_State* L) { lua_Debug ar; unsigned lev, n; bool_t extended; // [1]: error message (any type) assert( lua_gettop( L) == 1); // Don't do stack survey for cancelled lanes. // if( lua_touserdata( L, 1) == CANCEL_ERROR) { return 1; // just pass on } lua_pushlightuserdata( L, EXTENDED_STACK_TRACE_KEY); lua_gettable( L, LUA_REGISTRYINDEX); extended = lua_toboolean( L, -1); lua_pop( L, 1); // Place stack trace at 'registry[lane_error]' for the 'lua_pcall()' // caller to fetch. This bypasses the Lua 5.1 limitation of only one // return value from error handler to 'lua_pcall()' caller. // It's adequate to push stack trace as a table. This gives the receiver // of the stack best means to format it to their liking. Also, it allows // us to add more stack info later, if needed. // // table of { "sourcefile.lua:", ... } // STACK_GROW( L, 4); lua_newtable( L); // Best to start from level 1, but in some cases it might be a C function // and we don't get '.currentline' for that. It's okay - just keep level // and table index growing separate. --AKa 22-Jan-2009 // lev = 0; n = 1; while( lua_getstack( L, ++ lev, &ar)) { lua_getinfo( L, extended ? "Sln" : "Sl", &ar); if( extended) { lua_newtable( L); lua_pushstring( L, ar.source); lua_setfield( L, -2, "source"); lua_pushinteger( L, ar.currentline); lua_setfield( L, -2, "currentline"); lua_pushstring( L, ar.name); lua_setfield( L, -2, "name"); lua_pushstring( L, ar.namewhat); lua_setfield( L, -2, "namewhat"); lua_pushstring( L, ar.what); lua_setfield( L, -2, "what"); lua_rawseti(L, -2, n ++); } else if (ar.currentline > 0) { lua_pushinteger( L, n++ ); lua_pushfstring( L, "%s:%d", ar.short_src, ar.currentline ); lua_settable( L, -3 ); } } lua_pushlightuserdata( L, STACK_TRACE_KEY); lua_insert( L, -2); lua_settable( L, LUA_REGISTRYINDEX); assert( lua_gettop( L) == 1); return 1; // the untouched error value } #endif // ERROR_FULL_STACK LUAG_FUNC( set_debug_threadname) { // C s_lane structure is a light userdata upvalue struct s_lane* s = lua_touserdata( L, lua_upvalueindex( 1)); luaL_checktype( L, -1, LUA_TSTRING); // "name" // store a hidden reference in the registry to make sure the string is kept around even if a lane decides to manually change the "decoda_name" global... lua_pushlightuserdata( L, LG_set_debug_threadname); // "name" lud lua_pushvalue( L, -2); // "name" lud "name" lua_rawset( L, LUA_REGISTRYINDEX); // "name" s->debug_name = lua_tostring( L, -1); // keep a direct pointer on the string THREAD_SETNAME( s->debug_name); // to see VM name in Decoda debugger Virtual Machine window lua_setglobal( L, "decoda_name"); // return 0; } LUAG_FUNC( get_debug_threadname) { struct s_lane* const s = lua_toLane( L, 1); luaL_argcheck( L, lua_gettop( L) == 1, 2, "too many arguments"); lua_pushstring( L, s->debug_name); return 1; } LUAG_FUNC( set_thread_priority) { int const prio = luaL_checkint( L, 1); // public Lanes API accepts a generic range -3/+3 // that will be remapped into the platform-specific scheduler priority scheme // On some platforms, -3 is equivalent to -2 and +3 to +2 if( prio < THREAD_PRIO_MIN || prio > THREAD_PRIO_MAX) { return luaL_error( L, "priority out of range: %d..+%d (%d)", THREAD_PRIO_MIN, THREAD_PRIO_MAX, prio); } THREAD_SET_PRIORITY( prio); return 0; } #if USE_DEBUG_SPEW // can't use direct LUA_x errcode indexing because the sequence is not the same between Lua 5.1 and 5.2 :-( // LUA_ERRERR doesn't have the same value struct errcode_name { int code; char const* name; }; static struct errcode_name s_errcodes[] = { { LUA_OK, "LUA_OK"}, { LUA_YIELD, "LUA_YIELD"}, { LUA_ERRRUN, "LUA_ERRRUN"}, { LUA_ERRSYNTAX, "LUA_ERRSYNTAX"}, { LUA_ERRMEM, "LUA_ERRMEM"}, { LUA_ERRGCMM, "LUA_ERRGCMM"}, { LUA_ERRERR, "LUA_ERRERR"}, }; static char const* get_errcode_name( int _code) { int i; for( i = 0; i < 7; ++ i) { if( s_errcodes[i].code == _code) { return s_errcodes[i].name; } } return ""; } #endif // USE_DEBUG_SPEW #if THREADWAIT_METHOD == THREADWAIT_CONDVAR // implies THREADAPI == THREADAPI_PTHREAD static void thread_cleanup_handler( void* opaque) { struct s_lane* s= (struct s_lane*) opaque; MUTEX_LOCK( &s->done_lock); s->status = CANCELLED; SIGNAL_ONE( &s->done_signal); // wake up master (while 's->done_lock' is on) MUTEX_UNLOCK( &s->done_lock); } #endif // THREADWAIT_METHOD == THREADWAIT_CONDVAR //--- static THREAD_RETURN_T THREAD_CALLCONV lane_main( void* vs) { struct s_lane* s = (struct s_lane*) vs; int rc, rc2; lua_State* L = s->L; #if HAVE_LANE_TRACKING if( tracking_first) { tracking_add( s); } #endif // HAVE_LANE_TRACKING THREAD_MAKE_ASYNCH_CANCELLABLE(); THREAD_CLEANUP_PUSH( thread_cleanup_handler, s); s->status = RUNNING; // PENDING -> RUNNING // Tie "set_finalizer()" to the state // lua_pushcfunction( L, LG_set_finalizer ); populate_func_lookup_table( L, -1, "set_finalizer"); lua_setglobal( L, "set_finalizer"); // Tie "set_debug_threadname()" to the state // But don't register it in the lookup database because of the s_lane pointer upvalue lua_pushlightuserdata( L, s); lua_pushcclosure( L, LG_set_debug_threadname, 1); lua_setglobal( L, "set_debug_threadname" ); // Tie "cancel_test()" to the state // lua_pushcfunction( L, LG_cancel_test); populate_func_lookup_table( L, -1, "cancel_test"); lua_setglobal( L, "cancel_test"); #if ERROR_FULL_STACK // Tie "set_error_reporting()" to the state // lua_pushcfunction( L, LG_set_error_reporting); populate_func_lookup_table( L, -1, "set_error_reporting"); lua_setglobal( L, "set_error_reporting"); STACK_GROW( L, 1 ); lua_pushcfunction( L, lane_error); lua_insert( L, 1 ); // [1]: error handler // [2]: function to run // [3..top]: parameters // rc= lua_pcall( L, lua_gettop(L)-2, LUA_MULTRET, 1 /*error handler*/ ); // 0: no error, body return values are on the stack // LUA_ERRRUN: cancellation or a runtime error (error pushed on stack) // LUA_ERRMEM: memory allocation error // LUA_ERRERR: error while running the error handler (if any) assert( rc!=LUA_ERRERR ); // since we've authored it lua_remove(L,1); // remove error handler // Lua 5.1 error handler is limited to one return value; taking stack trace via registry if( rc != LUA_OK) { STACK_GROW(L,1); lua_pushlightuserdata( L, STACK_TRACE_KEY ); lua_gettable(L, LUA_REGISTRYINDEX); // yields nil if no stack was generated (in case of cancellation for example) // For cancellation, a stack trace isn't placed // assert( lua_istable(L,2) || (lua_touserdata(L,1)==CANCEL_ERROR) ); // Just leaving the stack trace table on the stack is enough to get // it through to the master. } #else // ERROR_FULL_STACK == 0 // This code does not use 'lane_error' // // [1]: function to run // [2..top]: parameters // rc = lua_pcall( L, lua_gettop( L) - 1, LUA_MULTRET, 0); // no error handler // LUA_OK(0): no error // LUA_ERRRUN(2): a runtime error (error pushed on stack) // LUA_ERRMEM(4): memory allocation error #endif // ERROR_FULL_STACK DEBUGSPEW_CODE( fprintf( stderr, INDENT_BEGIN "Lane %p body: %s (%s)\n" INDENT_END, L, get_errcode_name( rc), (lua_touserdata(L,1)==CANCEL_ERROR) ? "cancelled" : lua_typename( L, lua_type( L, 1)))); //STACK_DUMP(L); // Call finalizers, if the script has set them up. // rc2 = run_finalizers( L, rc); DEBUGSPEW_CODE( fprintf( stderr, INDENT_BEGIN "Lane %p finalizer: %s\n" INDENT_END, L, get_errcode_name( rc2))); if( rc2 != LUA_OK) // Error within a finalizer! { rc = rc2; // we're overruling the earlier script error or normal return // the finalizer generated an error, the error message [and stack trace] are pushed on the stack // remove the rest so that only the error message [and stack trace] remain on the stack #if ERROR_FULL_STACK lua_insert( L, 1); lua_insert( L, 1); lua_settop( L, 2); #else // ERROR_FULL_STACK == 0 lua_insert( L, 1); lua_settop( L, 1); #endif // ERROR_FULL_STACK } s->waiting_on = NULL; // just in case if( selfdestruct_remove( s)) // check and remove (under lock!) { // We're a free-running thread and no-one's there to clean us up. // lua_close( s->L); s->L = L = 0; // debug_name is a pointer to an interned string, that no longer exists when the state is closed s->debug_name = ""; lane_cleanup( s); MUTEX_LOCK( &selfdestruct_cs); // done with lua_close(), terminal shutdown sequence may proceed -- selfdestructing_count; MUTEX_UNLOCK( &selfdestruct_cs); } else { // leave results (1..top) or error message + stack trace (1..2) on the stack - master will copy them enum e_status st= (rc==0) ? DONE : (lua_touserdata(L,1)==CANCEL_ERROR) ? CANCELLED : ERROR_ST; // Posix no PTHREAD_TIMEDJOIN: // 'done_lock' protects the -> DONE|ERROR_ST|CANCELLED state change // #if THREADWAIT_METHOD == THREADWAIT_CONDVAR MUTEX_LOCK( &s->done_lock); { #endif // THREADWAIT_METHOD == THREADWAIT_CONDVAR s->status = st; #if THREADWAIT_METHOD == THREADWAIT_CONDVAR SIGNAL_ONE( &s->done_signal); // wake up master (while 's->done_lock' is on) } MUTEX_UNLOCK( &s->done_lock); #endif // THREADWAIT_METHOD == THREADWAIT_CONDVAR } THREAD_CLEANUP_POP( FALSE); return 0; // ignored } // --- If a client wants to transfer stuff of a given module from the current state to another Lane, the module must be required // with lanes.require, that will call the regular 'require', then populate the lookup database in the source lane // module = lanes.require( "modname") // upvalue[1]: _G.require LUAG_FUNC( require) { char const* name = lua_tostring( L, 1); int const nargs = lua_gettop( L); STACK_CHECK( L); DEBUGSPEW_CODE( fprintf( stderr, INDENT_BEGIN "lanes.require %s BEGIN\n" INDENT_END, name)); DEBUGSPEW_CODE( ++ debugspew_indent_depth); lua_pushvalue( L, lua_upvalueindex(1)); // "name" require lua_insert( L, 1); // require "name" lua_call( L, nargs, 1); // module populate_func_lookup_table( L, -1, name); DEBUGSPEW_CODE( fprintf( stderr, INDENT_BEGIN "lanes.require %s END\n" INDENT_END, name)); DEBUGSPEW_CODE( -- debugspew_indent_depth); STACK_END( L, 0); return 1; } LUAG_FUNC( thread_gc); #define GCCB_KEY (void*)LG_thread_gc //--- // lane_ud= thread_new( function, [libs_str], // [cancelstep_uint=0], // [prio_int=0], // [globals_tbl], // [package_tbl], // [required], // [gc_cb], // [... args ...] ) // // Upvalues: metatable to use for 'lane_ud' // LUAG_FUNC( thread_new) { lua_State* L2; struct s_lane* s; struct s_lane** ud; char const* libs = lua_tostring( L, 2); uint_t cs = luaG_optunsigned( L, 3, 0); int const prio = (int) luaL_optinteger( L, 4, 0); uint_t glob = lua_isnoneornil( L, 5) ? 0 : 5; uint_t package = lua_isnoneornil( L, 6) ? 0 : 6; uint_t required = lua_isnoneornil( L, 7) ? 0 : 7; uint_t gc_cb = lua_isnoneornil( L, 8) ? 0 : 8; #define FIXED_ARGS 8 uint_t args = lua_gettop(L) - FIXED_ARGS; // public Lanes API accepts a generic range -3/+3 // that will be remapped into the platform-specific scheduler priority scheme // On some platforms, -3 is equivalent to -2 and +3 to +2 if( prio < THREAD_PRIO_MIN || prio > THREAD_PRIO_MAX) { return luaL_error( L, "Priority out of range: %d..+%d (%d)", THREAD_PRIO_MIN, THREAD_PRIO_MAX, prio); } /* --- Create and prepare the sub state --- */ DEBUGSPEW_CODE( fprintf( stderr, INDENT_BEGIN "thread_new: setup\n" INDENT_END)); DEBUGSPEW_CODE( ++ debugspew_indent_depth); // populate with selected libraries at the same time // L2 = luaG_newstate( L, libs); STACK_GROW( L, 2); STACK_GROW( L2, 3); // give a default "Lua" name to the thread to see VM name in Decoda debugger lua_pushfstring( L2, "Lane #%p", L2); lua_setglobal( L2, "decoda_name"); ASSERT_L( lua_gettop(L2) == 0); DEBUGSPEW_CODE( fprintf( stderr, INDENT_BEGIN "thread_new: update 'package'\n" INDENT_END)); // package if( package != 0) { luaG_inter_copy_package( L, L2, package, eLM_LaneBody); } // modules to require in the target lane *before* the function is transfered! STACK_CHECK( L); STACK_CHECK( L2); if( required != 0) { int nbRequired = 1; DEBUGSPEW_CODE( fprintf( stderr, INDENT_BEGIN "thread_new: require 'required' list\n" INDENT_END)); DEBUGSPEW_CODE( ++ debugspew_indent_depth); // should not happen, was checked in lanes.lua before calling thread_new() if( lua_type( L, required) != LUA_TTABLE) { return luaL_error( L, "expected required module list as a table, got %s", luaL_typename( L, required)); } lua_pushnil( L); while( lua_next( L, required) != 0) { if( lua_type( L, -1) != LUA_TSTRING || lua_type( L, -2) != LUA_TNUMBER || lua_tonumber( L, -2) != nbRequired) { return luaL_error( L, "required module list should be a list of strings"); } else { // require the module in the target state, and populate the lookup table there too size_t len; char const* name = lua_tolstring( L, -1, &len); // require the module in the target lane STACK_GROW( L2, 2); STACK_CHECK( L2); lua_getglobal( L2, "require"); // require()? if( lua_isnil( L2, -1)) { lua_pop( L2, 1); // luaL_error( L, "cannot pre-require modules without loading 'package' library first"); } else { // if is it "lanes" or "lanes.core", make sure we have copied the initial settings over // which might not be the case if the libs list didn't include lanes.core or "*" if( strncmp( name, "lanes.core", len) == 0) // this works both both "lanes" and "lanes.core" because of len { luaG_copy_one_time_settings( L, L2, name); } lua_pushlstring( L2, name, len); // require() name if( lua_pcall( L2, 1, 1, 0) != LUA_OK) // ret/errcode { // propagate error to main state if any luaG_inter_move( L2, L, 1, eLM_LaneBody); // return lua_error( L); } STACK_MID( L2, 1); // after requiring the module, register the functions it exported in our name<->function database populate_func_lookup_table( L2, -1, name); STACK_MID( L2, 1); lua_pop( L2, 1); } STACK_END( L2, 0); } lua_pop( L, 1); ++ nbRequired; } DEBUGSPEW_CODE( -- debugspew_indent_depth); } STACK_END( L2, 0); STACK_END( L, 0); // Appending the specified globals to the global environment // *after* stdlibs have been loaded and modules required, in case we transfer references to native functions they exposed... // if( glob != 0) { DEBUGSPEW_CODE( fprintf( stderr, INDENT_BEGIN "thread_new: transfer globals\n" INDENT_END)); STACK_CHECK( L); STACK_CHECK( L2); if( !lua_istable( L, glob)) { return luaL_error( L, "Expected table, got %s", luaL_typename( L, glob)); } DEBUGSPEW_CODE( ++ debugspew_indent_depth); lua_pushnil( L); lua_pushglobaltable( L2); // Lua 5.2 wants us to push the globals table on the stack while( lua_next( L, glob)) { luaG_inter_copy( L, L2, 2, eLM_LaneBody); // moves the key/value pair to the L2 stack // assign it in L2's globals table lua_rawset( L2, -3); lua_pop( L, 1); } lua_pop( L2, 1); STACK_END( L2, 0); STACK_END( L, 0); DEBUGSPEW_CODE( -- debugspew_indent_depth); } ASSERT_L( lua_gettop( L2) == 0); // Lane main function // STACK_CHECK( L); if( lua_type( L, 1) == LUA_TFUNCTION) { int res; DEBUGSPEW_CODE( fprintf( stderr, INDENT_BEGIN "thread_new: transfer lane body\n" INDENT_END)); DEBUGSPEW_CODE( ++ debugspew_indent_depth); lua_pushvalue( L, 1); res = luaG_inter_move( L, L2, 1, eLM_LaneBody); // L->L2 DEBUGSPEW_CODE( -- debugspew_indent_depth); if( res != 0) { return luaL_error( L, "tried to copy unsupported types"); } STACK_MID( L, 0); } else if( lua_type( L, 1) == LUA_TSTRING) { // compile the string if( luaL_loadstring( L2, lua_tostring( L, 1)) != 0) { return luaL_error( L, "error when parsing lane function code"); } } ASSERT_L( lua_gettop( L2) == 1); ASSERT_L( lua_isfunction( L2, 1)); // revive arguments // if( args > 0) { int res; DEBUGSPEW_CODE( fprintf( stderr, INDENT_BEGIN "thread_new: transfer lane arguments\n" INDENT_END)); DEBUGSPEW_CODE( ++ debugspew_indent_depth); res = luaG_inter_copy( L, L2, args, eLM_LaneBody); // L->L2 DEBUGSPEW_CODE( -- debugspew_indent_depth); if( res != 0) { return luaL_error( L, "tried to copy unsupported types"); } } STACK_MID( L, 0); ASSERT_L( (uint_t)lua_gettop( L2) == 1 + args); ASSERT_L( lua_isfunction( L2, 1)); // 's' is allocated from heap, not Lua, since its life span may surpass // the handle's (if free running thread) // ud = lua_newuserdata( L, sizeof( struct s_lane*)); ASSERT_L( ud); s = *ud = malloc( sizeof( struct s_lane)); ASSERT_L( s); //memset( s, 0, sizeof(struct s_lane) ); s->L = L2; s->status = PENDING; s->waiting_on = NULL; s->debug_name = ""; s->cancel_request = CANCEL_NONE; #if THREADWAIT_METHOD == THREADWAIT_CONDVAR MUTEX_INIT( &s->done_lock); SIGNAL_INIT( &s->done_signal); #endif // THREADWAIT_METHOD == THREADWAIT_CONDVAR s->mstatus= NORMAL; s->selfdestruct_next= NULL; #if HAVE_LANE_TRACKING s->tracking_next = NULL; #endif // HAVE_LANE_TRACKING // Set metatable for the userdata // lua_pushvalue( L, lua_upvalueindex( 1)); lua_setmetatable( L, -2); STACK_MID( L, 1); // Create uservalue for the userdata // (this is where lane body return values will be stored when the handle is indexed by a numeric key) lua_newtable( L); // Store the gc_cb callback in the uservalue if( gc_cb > 0) { lua_pushlightuserdata( L, GCCB_KEY); lua_pushvalue( L, gc_cb); lua_rawset( L, -3); } lua_setuservalue( L, -2); // Store 's' in the lane's registry, for 'cancel_test()' (even if 'cs'==0 we still do cancel tests at pending send/receive). lua_pushlightuserdata( L2, CANCEL_TEST_KEY); lua_pushlightuserdata( L2, s); lua_rawset( L2, LUA_REGISTRYINDEX); if( cs) { lua_sethook( L2, cancel_hook, LUA_MASKCOUNT, cs); } DEBUGSPEW_CODE( fprintf( stderr, INDENT_BEGIN "thread_new: launching thread\n" INDENT_END)); THREAD_CREATE( &s->thread, lane_main, s, prio); STACK_END( L, 1); DEBUGSPEW_CODE( -- debugspew_indent_depth); return 1; } //--- // = thread_gc( lane_ud ) // // Cleanup for a thread userdata. If the thread is still executing, leave it // alive as a free-running thread (will clean up itself). // // * Why NOT cancel/kill a loose thread: // // At least timer system uses a free-running thread, they should be handy // and the issue of canceling/killing threads at gc is not very nice, either // (would easily cause waits at gc cycle, which we don't want). // LUAG_FUNC( thread_gc) { bool_t have_gc_cb = FALSE; struct s_lane* s = lua_toLane( L, 1); // ud // if there a gc callback? lua_getuservalue( L, 1); // ud uservalue lua_pushlightuserdata( L, GCCB_KEY); // ud uservalue __gc lua_rawget( L, -2); // ud uservalue gc_cb|nil if( !lua_isnil( L, -1)) { lua_remove( L, -2); // ud gc_cb|nil lua_pushstring( L, s->debug_name); // ud gc_cb name have_gc_cb = TRUE; } else { lua_pop( L, 2); // ud } // We can read 's->status' without locks, but not wait for it // test KILLED state first, as it doesn't need to enter the selfdestruct chain if( s->mstatus == KILLED) { // Make sure a kill has proceeded, before cleaning up the data structure. // // NO lua_close() in this case because we don't know where execution of the state was interrupted DEBUGSPEW_CODE( fprintf( stderr, "** Joining with a killed thread (needs testing) **")); // make sure the thread is no longer running, just like thread_join() if(! THREAD_ISNULL( s->thread)) { THREAD_WAIT( &s->thread, -1, &s->done_signal, &s->done_lock, &s->status); } if( s->status >= DONE && s->L) { // we know the thread was killed while the Lua VM was not doing anything: we should be able to close it without crashing // now, thread_cancel() will not forcefully kill a lane with s->status >= DONE, so I am not sure it can ever happen lua_close( s->L); s->L = 0; // just in case, but s will be freed soon so... s->debug_name = ""; } DEBUGSPEW_CODE( fprintf( stderr, "** Joined ok **")); } else if( s->status < DONE) { // still running: will have to be cleaned up later selfdestruct_add( s); assert( s->selfdestruct_next); if( have_gc_cb) { lua_pushliteral( L, "selfdestruct"); // ud gc_cb name status lua_call( L, 2, 0); // ud } return 0; } else if( s->L) { // no longer accessing the Lua VM: we can close right now lua_close( s->L); s->L = 0; // just in case, but s will be freed soon so... s->debug_name = ""; } // Clean up after a (finished) thread lane_cleanup( s); // do this after lane cleanup in case the callback triggers an error if( have_gc_cb) { lua_pushliteral( L, "closed"); // ud gc_cb name status lua_call( L, 2, 0); // ud } return 0; } // lane_h:cancel( [timeout] [, force [, forcekill_timeout]]) LUAG_FUNC( thread_cancel) { struct s_lane* s = lua_toLane( L, 1); double secs = 0.0; int force_i = 2; int forcekill_timeout_i = 3; if( lua_isnumber( L, 2)) { secs = lua_tonumber( L, 2); if( secs < 0.0 && lua_gettop( L) > 3) { return luaL_error( L, "can't force_kill a soft cancel"); } // negative timeout and force flag means we want to wake linda-waiting threads ++ force_i; ++ forcekill_timeout_i; } else if( lua_isnil( L, 2)) { ++ force_i; ++ forcekill_timeout_i; } { bool_t force = lua_toboolean( L, force_i); // FALSE if nothing there double forcekill_timeout = luaL_optnumber( L, forcekill_timeout_i, 0.0); switch( thread_cancel( L, s, secs, force, forcekill_timeout)) { case CR_Timeout: lua_pushboolean( L, 0); lua_pushstring( L, "timeout"); return 2; case CR_Cancelled: lua_pushboolean( L, 1); return 1; case CR_Killed: lua_pushboolean( L, 0); lua_pushstring( L, "killed"); return 2; } } // should never happen, only here to prevent the compiler from complaining of "not all control paths returning a value" return 0; } //--- // str= thread_status( lane ) // // Returns: "pending" not started yet // -> "running" started, doing its work.. // <-> "waiting" blocked in a receive() // -> "done" finished, results are there // / "error" finished at an error, error value is there // / "cancelled" execution cancelled by M (state gone) // static char const * thread_status_string( struct s_lane* s) { enum e_status st = s->status; // read just once (volatile) char const* str = (s->mstatus == KILLED) ? "killed" : // new to v3.3.0! (st == PENDING) ? "pending" : (st == RUNNING) ? "running" : // like in 'co.status()' (st == WAITING) ? "waiting" : (st == DONE) ? "done" : (st == ERROR_ST) ? "error" : (st == CANCELLED) ? "cancelled" : NULL; return str; } static int push_thread_status( lua_State* L, struct s_lane* s) { char const* const str = thread_status_string( s); ASSERT_L( str); lua_pushstring( L, str); return 1; } //--- // [...] | [nil, err_any, stack_tbl]= thread_join( lane_ud [, wait_secs=-1] ) // // timeout: returns nil // done: returns return values (0..N) // error: returns nil + error value [+ stack table] // cancelled: returns nil // LUAG_FUNC( thread_join) { struct s_lane* const s = lua_toLane( L, 1); double wait_secs = luaL_optnumber( L, 2, -1.0); lua_State* L2 = s->L; int ret; bool_t done; done = THREAD_ISNULL( s->thread) || THREAD_WAIT( &s->thread, wait_secs, &s->done_signal, &s->done_lock, &s->status); if( !done || !L2) { return 0; // timeout: pushes none, leaves 'L2' alive } // Thread is DONE/ERROR_ST/CANCELLED; all ours now if( s->mstatus == KILLED) // OS thread was killed if thread_cancel was forced { // in that case, even if the thread was killed while DONE/ERROR_ST/CANCELLED, ignore regular return values STACK_GROW( L, 1); lua_pushnil( L); lua_pushliteral( L, "killed"); ret = 2; } else { // debug_name is a pointer to string possibly interned in the lane's state, that no longer exists when the state is closed // so store it in the userdata uservalue at a key that can't possibly collide securize_debug_threadname( L, s); switch( s->status) { case DONE: { uint_t n = lua_gettop( L2); // whole L2 stack if( (n > 0) && (luaG_inter_move( L2, L, n, eLM_LaneBody) != 0)) { return luaL_error( L, "tried to copy unsupported types"); } ret = n; } break; case ERROR_ST: lua_pushnil( L); if( luaG_inter_move( L2, L, 1 + ERROR_FULL_STACK, eLM_LaneBody) != 0) // error message at [-2], stack trace at [-1] { return luaL_error( L, "tried to copy unsupported types"); } ret = 2 + ERROR_FULL_STACK; break; case CANCELLED: ret= 0; break; default: DEBUGSPEW_CODE( fprintf( stderr, "Status: %d\n", s->status)); ASSERT_L( FALSE); ret = 0; } lua_close( L2); } s->L = 0; return ret; } //--- // thread_index( ud, key) -> value // // If key is found in the environment, return it // If key is numeric, wait until the thread returns and populate the environment with the return values // If the return values signal an error, propagate it // If key is "status" return the thread status // Else raise an error LUAG_FUNC( thread_index) { int const UD = 1; int const KEY = 2; int const USR = 3; struct s_lane* const s = lua_toLane( L, UD); ASSERT_L( lua_gettop( L) == 2); STACK_GROW( L, 8); // up to 8 positions are needed in case of error propagation // If key is numeric, wait until the thread returns and populate the environment with the return values if( lua_type( L, KEY) == LUA_TNUMBER) { // first, check that we don't already have an environment that holds the requested value { // If key is found in the uservalue, return it lua_getuservalue( L, UD); lua_pushvalue( L, KEY); lua_rawget( L, USR); if( !lua_isnil( L, -1)) { return 1; } lua_pop( L, 1); } { // check if we already fetched the values from the thread or not bool_t fetched; lua_Integer key = lua_tointeger( L, KEY); lua_pushinteger( L, 0); lua_rawget( L, USR); fetched = !lua_isnil( L, -1); lua_pop( L, 1); // back to our 2 args + uservalue on the stack if( !fetched) { lua_pushinteger( L, 0); lua_pushboolean( L, 1); lua_rawset( L, USR); // wait until thread has completed lua_pushcfunction( L, LG_thread_join); lua_pushvalue( L, UD); lua_call( L, 1, LUA_MULTRET); // all return values are on the stack, at slots 4+ switch( s->status) { default: if( s->mstatus != KILLED) { // this is an internal error, we probably never get here lua_settop( L, 0); lua_pushliteral( L, "Unexpected status: "); lua_pushstring( L, thread_status_string( s)); lua_concat( L, 2); lua_error( L); break; } // fall through if we are killed, as we got nil, "killed" on the stack case DONE: // got regular return values { int i, nvalues = lua_gettop( L) - 3; for( i = nvalues; i > 0; -- i) { // pop the last element of the stack, to store it in the uservalue at its proper index lua_rawseti( L, USR, i); } } break; case ERROR_ST: // got 3 values: nil, errstring, callstack table // me[-2] could carry the stack table, but even // me[-1] is rather unnecessary (and undocumented); // use ':join()' instead. --AKa 22-Jan-2009 ASSERT_L( lua_isnil( L, 4) && !lua_isnil( L, 5) && lua_istable( L, 6)); // store errstring at key -1 lua_pushnumber( L, -1); lua_pushvalue( L, 5); lua_rawset( L, USR); break; case CANCELLED: // do nothing break; } } lua_settop( L, 3); // UD KEY ENV if( key != -1) { lua_pushnumber( L, -1); // UD KEY ENV -1 lua_rawget( L, USR); // UD KEY ENV "error" if( !lua_isnil( L, -1)) // an error was stored { // Note: Lua 5.1 interpreter is not prepared to show // non-string errors, so we use 'tostring()' here // to get meaningful output. --AKa 22-Jan-2009 // // Also, the stack dump we get is no good; it only // lists our internal Lanes functions. There seems // to be no way to switch it off, though. // // Level 3 should show the line where 'h[x]' was read // but this only seems to work for string messages // (Lua 5.1.4). No idea, why. --AKa 22-Jan-2009 lua_getmetatable( L, UD); // UD KEY ENV "error" mt lua_getfield( L, -1, "cached_error"); // UD KEY ENV "error" mt error() lua_getfield( L, -2, "cached_tostring"); // UD KEY ENV "error" mt error() tostring() lua_pushvalue( L, 4); // UD KEY ENV "error" mt error() tostring() "error" lua_call( L, 1, 1); // tostring( errstring) -- just in case // UD KEY ENV "error" mt error() "error" lua_pushinteger( L, 3); // UD KEY ENV "error" mt error() "error" 3 lua_call( L, 2, 0); // error( tostring( errstring), 3) // UD KEY ENV "error" mt } else { lua_pop( L, 1); // back to our 3 arguments on the stack } } lua_rawgeti( L, USR, (int)key); } return 1; } if( lua_type( L, KEY) == LUA_TSTRING) { char const * const keystr = lua_tostring( L, KEY); lua_settop( L, 2); // keep only our original arguments on the stack if( strcmp( keystr, "status") == 0) { return push_thread_status( L, s); // push the string representing the status } // return UD.metatable[key] lua_getmetatable( L, UD); // UD KEY mt lua_replace( L, -3); // mt KEY lua_rawget( L, -2); // mt value // only "cancel" and "join" are registered as functions, any other string will raise an error if( lua_iscfunction( L, -1)) { return 1; } return luaL_error( L, "can't index a lane with '%s'", keystr); } // unknown key lua_getmetatable( L, UD); lua_getfield( L, -1, "cached_error"); lua_pushliteral( L, "Unknown key: "); lua_pushvalue( L, KEY); lua_concat( L, 2); lua_call( L, 1, 0); // error( "Unknown key: " .. key) -> doesn't return return 0; } #if HAVE_LANE_TRACKING //--- // threads() -> {}|nil // // Return a list of all known lanes LUAG_FUNC( threads) { int const top = lua_gettop( L); // List _all_ still running threads // MUTEX_LOCK( &tracking_cs); if( tracking_first && tracking_first != TRACKING_END) { struct s_lane* s = tracking_first; lua_newtable( L); // {} while( s != TRACKING_END) { lua_pushstring( L, s->debug_name); // {} "name" push_thread_status( L, s); // {} "name" "status" lua_rawset( L, -3); // {} s = s->tracking_next; } } MUTEX_UNLOCK( &tracking_cs); return lua_gettop( L) - top; } #endif // HAVE_LANE_TRACKING /* * ############################################################################################### * ######################################## Timer support ######################################## * ############################################################################################### */ /* * secs= now_secs() * * Returns the current time, as seconds (millisecond resolution). */ LUAG_FUNC( now_secs ) { lua_pushnumber( L, now_secs() ); return 1; } /* * wakeup_at_secs= wakeup_conv( date_tbl ) */ LUAG_FUNC( wakeup_conv ) { int year, month, day, hour, min, sec, isdst; struct tm t; memset( &t, 0, sizeof( t)); // // .year (four digits) // .month (1..12) // .day (1..31) // .hour (0..23) // .min (0..59) // .sec (0..61) // .yday (day of the year) // .isdst (daylight saving on/off) STACK_CHECK( L); lua_getfield( L, 1, "year" ); year= (int)lua_tointeger(L,-1); lua_pop(L,1); lua_getfield( L, 1, "month" ); month= (int)lua_tointeger(L,-1); lua_pop(L,1); lua_getfield( L, 1, "day" ); day= (int)lua_tointeger(L,-1); lua_pop(L,1); lua_getfield( L, 1, "hour" ); hour= (int)lua_tointeger(L,-1); lua_pop(L,1); lua_getfield( L, 1, "min" ); min= (int)lua_tointeger(L,-1); lua_pop(L,1); lua_getfield( L, 1, "sec" ); sec= (int)lua_tointeger(L,-1); lua_pop(L,1); // If Lua table has '.isdst' we trust that. If it does not, we'll let // 'mktime' decide on whether the time is within DST or not (value -1). // lua_getfield( L, 1, "isdst" ); isdst= lua_isboolean(L,-1) ? lua_toboolean(L,-1) : -1; lua_pop(L,1); STACK_END( L, 0); t.tm_year= year-1900; t.tm_mon= month-1; // 0..11 t.tm_mday= day; // 1..31 t.tm_hour= hour; // 0..23 t.tm_min= min; // 0..59 t.tm_sec= sec; // 0..60 t.tm_isdst= isdst; // 0/1/negative lua_pushnumber( L, (double) mktime( &t)); // ms=0 return 1; } /* * ############################################################################################### * ######################################## Module linkage ####################################### * ############################################################################################### */ static const struct luaL_Reg lanes_functions [] = { {"linda", LG_linda}, {"now_secs", LG_now_secs}, {"wakeup_conv", LG_wakeup_conv}, {"set_thread_priority", LG_set_thread_priority}, {"nameof", luaG_nameof}, {"set_singlethreaded", LG_set_singlethreaded}, {NULL, NULL} }; /* ** One-time initializations * settings table it at position 1 on the stack */ static void init_once_LOCKED( lua_State* L) { initialize_on_state_create( L); STACK_CHECK( L); lua_getfield( L, 1, "verbose_errors"); GVerboseErrors = lua_toboolean( L, -1); lua_pop( L, 1); STACK_MID( L, 0); #if (defined PLATFORM_WIN32) || (defined PLATFORM_POCKETPC) now_secs(); // initialize 'now_secs()' internal offset #endif #if (defined PLATFORM_OSX) && (defined _UTILBINDTHREADTOCPU) chudInitialize(); #endif #if HAVE_LANE_TRACKING MUTEX_INIT( &tracking_cs); lua_getfield( L, 1, "track_lanes"); tracking_first = lua_toboolean( L, -1) ? TRACKING_END : NULL; lua_pop( L, 1); STACK_MID( L, 0); #endif // HAVE_LANE_TRACKING // Locks for 'tools.c' inc/dec counters // MUTEX_INIT( &deep_lock); MUTEX_INIT( &mtid_lock); // Serialize calls to 'require' from now on, also in the primary state // MUTEX_RECURSIVE_INIT( &require_cs); serialize_require( L); // Linked chains handling // MUTEX_INIT( &selfdestruct_cs); //--- // Linux needs SCHED_RR to change thread priorities, and that is only // allowed for sudo'ers. SCHED_OTHER (default) has no priorities. // SCHED_OTHER threads are always lower priority than SCHED_RR. // // ^-- those apply to 2.6 kernel. IF **wishful thinking** these // constraints will change in the future, non-sudo priorities can // be enabled also for Linux. // #ifdef PLATFORM_LINUX sudo = (geteuid() == 0); // we are root? // If lower priorities (-2..-1) are wanted, we need to lift the main // thread to SCHED_RR and 50 (medium) level. Otherwise, we're always below // the launched threads (even -2). // #ifdef LINUX_SCHED_RR if( sudo) { struct sched_param sp; sp.sched_priority = _PRIO_0; PT_CALL( pthread_setschedparam( pthread_self(), SCHED_RR, &sp)); } #endif // LINUX_SCHED_RR #endif // PLATFORM_LINUX { char const* err = init_keepers( L); if (err) { (void) luaL_error( L, "Unable to initialize: %s", err ); } } // Initialize 'timer_deep'; a common Linda object shared by all states // ASSERT_L( timer_deep == NULL); // proxy_ud= deep_userdata( idfunc ) // lua_pushliteral( L, "lanes-timer"); // push a name for debug purposes luaG_deep_userdata( L, linda_id); STACK_MID( L, 2); lua_remove( L, -2); // remove the name as we no longer need it ASSERT_L( lua_isuserdata(L,-1)); // Proxy userdata contents is only a 'DEEP_PRELUDE*' pointer // timer_deep = * (DEEP_PRELUDE**) lua_touserdata( L, -1); ASSERT_L( timer_deep && (timer_deep->refcount == 1) && timer_deep->deep); // The host Lua state must always have a reference to this Linda object in order for the timer_deep pointer to be valid. // So store a reference that we will never actually use. // at the same time, use this object as a 'desinit' marker: // when the main lua State is closed, this object will be GC'ed { lua_newuserdata( L, 1); lua_newtable( L); lua_getfield( L, 1, "shutdown_timeout"); lua_pushcclosure( L, selfdestruct_gc, 1); lua_setfield( L, -2, "__gc"); lua_pushliteral( L, "AtExit"); lua_setfield( L, -2, "__metatable"); lua_setmetatable( L, -2); } lua_insert( L, -2); // Swap key with the Linda object lua_rawset( L, LUA_REGISTRYINDEX); // we'll need this everytime we transfer some C function from/to this state lua_newtable( L); lua_setfield( L, LUA_REGISTRYINDEX, LOOKUP_REGKEY); STACK_END( L, 0); } static volatile long s_initCount = 0; // upvalue 1: module name // upvalue 2: module table // param 1: settings table LUAG_FUNC( configure) { char const* name = luaL_checkstring( L, lua_upvalueindex( 1)); _ASSERT_L( L, lua_type( L, 1) == LUA_TTABLE); STACK_CHECK( L); DEBUGSPEW_CODE( fprintf( stderr, INDENT_BEGIN "%p: lanes.configure() BEGIN\n" INDENT_END, L)); DEBUGSPEW_CODE( ++ debugspew_indent_depth); // not in init_once_LOCKED because we can have several hosted "master" Lua states where Lanes is require()d. lua_getfield( L, 1, "protect_allocator"); // settings protect_allocator if( lua_toboolean( L, -1)) { void* ud; lua_Alloc allocf = lua_getallocf( L, &ud); if( allocf != protected_lua_Alloc) // just in case { struct ProtectedAllocator_s* s = (struct ProtectedAllocator_s*) allocf( ud, NULL, 0, sizeof( struct ProtectedAllocator_s)); s->allocf = allocf; s->ud = ud; MUTEX_INIT( &s->lock); lua_setallocf( L, protected_lua_Alloc, s); } } lua_pop( L, 1); // settings STACK_MID( L, 0); /* ** Making one-time initializations. ** ** When the host application is single-threaded (and all threading happens via Lanes) ** there is no problem. But if the host is multithreaded, we need to lock around the ** initializations. */ #if THREADAPI == THREADAPI_WINDOWS { static volatile int /*bool*/ go_ahead; // = 0 if( InterlockedCompareExchange( &s_initCount, 1, 0) == 0) { init_once_LOCKED( L); go_ahead = 1; // let others pass } else { while( !go_ahead) { Sleep(1); } // changes threads } } #else // THREADAPI == THREADAPI_PTHREAD if( s_initCount == 0) { static pthread_mutex_t my_lock = PTHREAD_MUTEX_INITIALIZER; pthread_mutex_lock( &my_lock); { // Recheck now that we're within the lock // if( s_initCount == 0) { init_once_LOCKED( L); s_initCount = 1; } } pthread_mutex_unlock( &my_lock); } #endif // THREADAPI == THREADAPI_PTHREAD // Retrieve main module interface table lua_pushvalue( L, lua_upvalueindex( 2)); // settings M // remove configure() (this function) from the module interface lua_pushnil( L); // settings M nil lua_setfield( L, -2, "configure"); // settings M // add functions to the module's table luaG_registerlibfuncs( L, lanes_functions); #if HAVE_LANE_TRACKING // register core.threads() only if settings say it should be available if( tracking_first != NULL) { lua_pushcfunction( L, LG_threads); // settings M LG_threads() lua_setfield( L, -2, "threads"); } #endif // HAVE_LANE_TRACKING STACK_MID( L, 1); ASSERT_L( timer_deep != NULL); // initialized by init_once_LOCKED luaG_push_proxy( L, linda_id, (DEEP_PRELUDE*) timer_deep); // settings M timer_deep lua_setfield( L, -2, "timer_gateway"); // settings M STACK_MID( L, 1); // prepare the metatable for threads // contains keys: { __gc, __index, cached_error, cached_tostring, cancel, join, get_debug_threadname } // if( luaL_newmetatable( L, "Lane")) // settings M mt { lua_pushcfunction( L, LG_thread_gc); // settings M mt LG_thread_gc lua_setfield( L, -2, "__gc"); // settings M mt lua_pushcfunction( L, LG_thread_index); // settings M mt LG_thread_index lua_setfield( L, -2, "__index"); // settings M mt lua_getglobal( L, "error"); // settings M mt error ASSERT_L( lua_isfunction( L, -1)); lua_setfield( L, -2, "cached_error"); // settings M mt lua_getglobal( L, "tostring"); // settings M mt tostring ASSERT_L( lua_isfunction( L, -1)); lua_setfield( L, -2, "cached_tostring"); // settings M mt lua_pushcfunction( L, LG_thread_join); // settings M mt LG_thread_join lua_setfield( L, -2, "join"); // settings M mt lua_pushcfunction( L, LG_get_debug_threadname); // settings M mt LG_get_debug_threadname lua_setfield( L, -2, "get_debug_threadname"); // settings M mt lua_pushcfunction( L, LG_thread_cancel); // settings M mt LG_thread_cancel lua_setfield( L, -2, "cancel"); // settings M mt lua_pushliteral( L, "Lane"); // settings M mt "Lane" lua_setfield( L, -2, "__metatable"); // settings M mt } lua_pushcclosure( L, LG_thread_new, 1); // settings M LG_thread_new lua_setfield( L, -2, "thread_new"); // settings M // we can't register 'lanes.require' normally because we want to create an upvalued closure lua_getglobal( L, "require"); // settings M require lua_pushcclosure( L, LG_require, 1); // settings M lanes.require lua_setfield( L, -2, "require"); // settings M lua_pushstring(L, VERSION); // settings M VERSION lua_setfield(L, -2, "version"); // settings M lua_pushinteger(L, THREAD_PRIO_MAX); // settings M THREAD_PRIO_MAX lua_setfield(L, -2, "max_prio"); // settings M lua_pushlightuserdata( L, CANCEL_ERROR); // settings M CANCEL_ERROR lua_setfield(L, -2, "cancel_error"); // settings M // register all native functions found in that module in the transferable functions database // we process it before _G because we don't want to find the module when scanning _G (this would generate longer names) // for example in package.loaded["lanes.core"].* populate_func_lookup_table( L, -1, name); // record all existing C/JIT-fast functions // Lua 5.2 no longer has LUA_GLOBALSINDEX: we must push globals table on the stack lua_pushglobaltable( L); // settings M _G populate_func_lookup_table( L, -1, NULL); lua_pop( L, 1); // settings M // set _R[CONFIG_REGKEY] = settings lua_pushvalue( L, -2); // settings M settings lua_setfield( L, LUA_REGISTRYINDEX, CONFIG_REGKEY); // settings M lua_pop( L, 1); // settings STACK_END( L, 0); DEBUGSPEW_CODE( fprintf( stderr, INDENT_BEGIN "%p: lanes.configure() END\n" INDENT_END, L)); DEBUGSPEW_CODE( -- debugspew_indent_depth); // Return the settings table return 1; } #if defined PLATFORM_WIN32 && !defined NDEBUG #include #include void signal_handler( int signal) { if( signal == SIGABRT) { _cprintf( "caught abnormal termination!"); abort(); } } // helper to have correct callstacks when crashing a Win32 running on 64 bits Windows // don't forget to toggle Debug/Exceptions/Win32 in visual Studio too! static volatile long s_ecoc_initCount = 0; static volatile int s_ecoc_go_ahead = 0; static void EnableCrashingOnCrashes( void) { if( InterlockedCompareExchange( &s_ecoc_initCount, 1, 0) == 0) { typedef BOOL (WINAPI* tGetPolicy)( LPDWORD lpFlags); typedef BOOL (WINAPI* tSetPolicy)( DWORD dwFlags); typedef void (* SignalHandlerPointer)( int); SignalHandlerPointer previousHandler = signal( SIGABRT, signal_handler); const DWORD EXCEPTION_SWALLOWING = 0x1; HMODULE kernel32 = LoadLibraryA("kernel32.dll"); tGetPolicy pGetPolicy = (tGetPolicy)GetProcAddress(kernel32, "GetProcessUserModeExceptionPolicy"); tSetPolicy pSetPolicy = (tSetPolicy)GetProcAddress(kernel32, "SetProcessUserModeExceptionPolicy"); if( pGetPolicy && pSetPolicy) { DWORD dwFlags; if( pGetPolicy( &dwFlags)) { // Turn off the filter pSetPolicy( dwFlags & ~EXCEPTION_SWALLOWING); } } s_ecoc_go_ahead = 1; // let others pass } else { while( !s_ecoc_go_ahead) { Sleep(1); } // changes threads } } #endif // PLATFORM_WIN32 int LANES_API luaopen_lanes_core( lua_State* L) { #if defined PLATFORM_WIN32 && !defined NDEBUG EnableCrashingOnCrashes(); #endif // defined PLATFORM_WIN32 && !defined NDEBUG STACK_GROW( L, 4); STACK_CHECK( L); // Create main module interface table // we only have 1 closure, which must be called to configure Lanes lua_newtable( L); // M lua_pushvalue( L, 1); // M "lanes.core" lua_pushvalue( L, -2); // M "lanes.core" M lua_pushcclosure( L, LG_configure, 2); // M LG_configure() lua_getfield( L, LUA_REGISTRYINDEX, CONFIG_REGKEY); // M LG_configure() settings if( !lua_isnil( L, -1)) // this is not the first require "lanes.core": call configure() immediately { lua_pushvalue( L, -1); // M LG_configure() settings settings lua_setfield( L, -4, "settings"); // M LG_configure() settings lua_call( L, 1, 0); // M } else { // will do nothing on first invocation, as we haven't stored settings in the registry yet lua_setfield( L, -3, "settings"); // M LG_configure() lua_setfield( L, -2, "configure"); // M } STACK_END( L, 1); return 1; } static int default_luaopen_lanes( lua_State* L) { int rc = luaL_loadfile( L, "lanes.lua") || lua_pcall( L, 0, 1, 0); if( rc != LUA_OK) { return luaL_error( L, "failed to initialize embedded Lanes"); } return 1; } // call this instead of luaopen_lanes_core() when embedding Lua and Lanes in a custom application void LANES_API luaopen_lanes_embedded( lua_State* L, lua_CFunction _luaopen_lanes) { STACK_CHECK( L); // pre-require lanes.core so that when lanes.lua calls require "lanes.core" it finds it is already loaded luaL_requiref( L, "lanes.core", luaopen_lanes_core, 0); // ... lanes.core lua_pop( L, 1); // ... STACK_MID( L, 0); // call user-provided function that runs the chunk "lanes.lua" from wherever they stored it luaL_requiref( L, "lanes", _luaopen_lanes ? _luaopen_lanes : default_luaopen_lanes, 0); // ... lanes STACK_END( L, 1); }