From 348f3f2ee2d2707e30658c3600e05309ad0e72bf Mon Sep 17 00:00:00 2001 From: Lukas Larsson Date: Thu, 10 Dec 2015 10:59:34 +0100 Subject: erts: Add enif_is_process/port_alive --- erts/doc/src/erl_nif.xml | 25 ++++++++++ erts/emulator/beam/erl_nif.c | 70 ++++++++++++++++++++++++++- erts/emulator/beam/erl_nif.h | 7 ++- erts/emulator/beam/erl_nif_api_funcs.h | 6 +++ erts/emulator/test/nif_SUITE.erl | 25 +++++++++- erts/emulator/test/nif_SUITE_data/nif_SUITE.c | 26 +++++++++- 6 files changed, 154 insertions(+), 5 deletions(-) diff --git a/erts/doc/src/erl_nif.xml b/erts/doc/src/erl_nif.xml index e62f5792a5..6befdc124b 100644 --- a/erts/doc/src/erl_nif.xml +++ b/erts/doc/src/erl_nif.xml @@ -532,6 +532,14 @@ typedef struct { environment. ErlNifPid is an opaque type.

+ ErlNifPort + +

ErlNifPort is a port identifier. In contrast to + port id terms (instances of ERL_NIF_TERM), ErlNifPort's are self + contained and not bound to any + environment. ErlNifPort + is an opaque type.

+ ErlNifResourceType @@ -801,6 +809,12 @@ typedef enum { pid variable *pid from it and return true. Otherwise return false. No check if the process is alive is done.

+ intenif_get_local_port(ErlNifEnv* env, ERL_NIF_TERM term, ErlNifPort* port_id) + Read an local port term +

If term is the port of a node local port, initialize the + port variable *port_id from it and return true. Otherwise return false. + No check if the port is alive is done.

 + intenif_get_list_cell(ErlNifEnv* env, ERL_NIF_TERM list, ERL_NIF_TERM* head, ERL_NIF_TERM* tail) Get head and tail from a list

Set *head and *tail from @@ -969,6 +983,17 @@ typedef enum { Determine if a term is a port

Return true if term is a port.

 + intenif_is_port_alive(ErlNifEnv* env, ErlNifPort *port_id) + Determine if a local port is alive or not. +

Return true if port_id is currently alive.

+

This function can only be used in a from a NIF-calling thread.

 + + intenif_is_process_alive(ErlNifEnv* env, ErlNifPid *pid) + Determine if a local process is alive or not. +

Return true if pid is currently alive.

+

This function is only thread-safe when the emulator with SMP support is used. + It can only be used in a non-SMP emulator from a NIF-calling thread.

 + intenif_is_ref(ErlNifEnv* env, ERL_NIF_TERM term) Determine if a term is a reference

Return true if term is a reference.

 diff --git a/erts/emulator/beam/erl_nif.c b/erts/emulator/beam/erl_nif.c index 703c96777a..8440fd26b5 100644 --- a/erts/emulator/beam/erl_nif.c +++ b/erts/emulator/beam/erl_nif.c @@ -404,12 +404,28 @@ static int is_offheap(const ErlOffHeap* oh) ErlNifPid* enif_self(ErlNifEnv* caller_env, ErlNifPid* pid) { + if (caller_env->proc->common.id == ERTS_INVALID_PID) + return NULL; pid->pid = caller_env->proc->common.id; return pid; } + int enif_get_local_pid(ErlNifEnv* env, ERL_NIF_TERM term, ErlNifPid* pid) { - return is_internal_pid(term) ? (pid->pid=term, 1) : 0; + if (is_internal_pid(term)) { + pid->pid=term; + return 1; + } + return 0; +} + +int enif_get_local_port(ErlNifEnv* env, ERL_NIF_TERM term, ErlNifPort* port) +{ + if (is_internal_port(term)) { + port->port_id=term; + return 1; + } + return 0; } int enif_is_atom(ErlNifEnv* env, ERL_NIF_TERM term) @@ -1158,6 +1174,58 @@ int enif_make_reverse_list(ErlNifEnv* env, ERL_NIF_TERM term, ERL_NIF_TERM *list return 1; } +int enif_is_process_alive(ErlNifEnv* env, ErlNifPid *proc) +{ + ErtsProcLocks rp_locks = 0; /* We don't need any locks, + just to check if it is alive */ + Eterm target = proc->pid; + Process* rp; + Process* c_p; + int scheduler = erts_get_scheduler_id() != 0; + + if (env != NULL) { + c_p = env->proc; + if (target == c_p->common.id) { + /* We are alive! */ + return 1; + } + } + else { +#ifdef ERTS_SMP + c_p = NULL; +#else + erts_exit(ERTS_ABORT_EXIT,"enif_is_process_alive: " + "env==NULL on non-SMP VM"); +#endif + } + + rp = (scheduler + ? erts_proc_lookup(target) + : erts_pid2proc_opt(c_p, ERTS_PROC_LOCK_MAIN, + target, rp_locks, ERTS_P2P_FLG_INC_REFC)); + if (rp == NULL) { + ASSERT(env == NULL || target != c_p->common.id); + return 0; + } else { + if (!scheduler) + erts_proc_dec_refc(rp); + return 1; + } +} + +int enif_is_port_alive(ErlNifEnv *env, ErlNifPort *port) +{ + /* only allowed if called from scheduler */ + if (erts_get_scheduler_id() == 0) + erts_exit(ERTS_ABORT_EXIT,"enif_is_port_alive: called from non-scheduler"); + + return erts_port_lookup( + port->port_id, + (erts_port_synchronous_ops + ? ERTS_PORT_SFLGS_INVALID_DRIVER_LOOKUP + : ERTS_PORT_SFLGS_INVALID_LOOKUP)) != NULL; +} + ERL_NIF_TERM enif_now_time(ErlNifEnv *env) { diff --git a/erts/emulator/beam/erl_nif.h b/erts/emulator/beam/erl_nif.h index 959fcb5412..6ee22a693c 100644 --- a/erts/emulator/beam/erl_nif.h +++ b/erts/emulator/beam/erl_nif.h @@ -150,7 +150,12 @@ typedef enum typedef struct { ERL_NIF_TERM pid; /* internal, may change */ -}ErlNifPid; +} ErlNifPid; + +typedef struct +{ + ERL_NIF_TERM port_id; /* internal, may change */ +}ErlNifPort; typedef ErlDrvSysInfo ErlNifSysInfo; diff --git a/erts/emulator/beam/erl_nif_api_funcs.h b/erts/emulator/beam/erl_nif_api_funcs.h index 3fe60e3df8..21864c8b35 100644 --- a/erts/emulator/beam/erl_nif_api_funcs.h +++ b/erts/emulator/beam/erl_nif_api_funcs.h @@ -166,6 +166,9 @@ ERL_NIF_API_FUNC_DECL(ErlNifTime, enif_convert_time_unit, (ErlNifTime, ErlNifTim ERL_NIF_API_FUNC_DECL(ERL_NIF_TERM, enif_now_time, (ErlNifEnv *env)); ERL_NIF_API_FUNC_DECL(ERL_NIF_TERM, enif_cpu_time, (ErlNifEnv *env)); ERL_NIF_API_FUNC_DECL(ERL_NIF_TERM, enif_make_unique_integer, (ErlNifEnv *env, ErlNifUniqueInteger properties)); +ERL_NIF_API_FUNC_DECL(int, enif_is_process_alive, (ErlNifEnv *env, ErlNifPid *pid)); +ERL_NIF_API_FUNC_DECL(int, enif_is_port_alive, (ErlNifEnv *env, ErlNifPort *port_id)); +ERL_NIF_API_FUNC_DECL(int, enif_get_local_port, (ErlNifEnv* env, ERL_NIF_TERM, ErlNifPort* port_id)); /* ** ADD NEW ENTRIES HERE (before this comment) !!! @@ -324,6 +327,9 @@ ERL_NIF_API_FUNC_DECL(int,enif_is_on_dirty_scheduler,(ErlNifEnv*)); # define enif_now_time ERL_NIF_API_FUNC_MACRO(enif_now_time) # define enif_cpu_time ERL_NIF_API_FUNC_MACRO(enif_cpu_time) # define enif_make_unique_integer ERL_NIF_API_FUNC_MACRO(enif_make_unique_integer) +# define enif_is_process_alive ERL_NIF_API_FUNC_MACRO(enif_is_process_alive) +# define enif_is_port_alive ERL_NIF_API_FUNC_MACRO(enif_is_port_alive) +# define enif_get_local_port ERL_NIF_API_FUNC_MACRO(enif_get_local_port) /* ** ADD NEW ENTRIES HERE (before this comment) diff --git a/erts/emulator/test/nif_SUITE.erl b/erts/emulator/test/nif_SUITE.erl index d3bf91092f..3202986ce7 100644 --- a/erts/emulator/test/nif_SUITE.erl +++ b/erts/emulator/test/nif_SUITE.erl @@ -43,7 +43,8 @@ nif_exception/1, call_nif_exception/1, nif_nan_and_inf/1, nif_atom_too_long/1, nif_monotonic_time/1, nif_time_offset/1, nif_convert_time_unit/1, - nif_now_time/1, nif_cpu_time/1, nif_unique_integer/1 + nif_now_time/1, nif_cpu_time/1, nif_unique_integer/1, + nif_is_process_alive/1, nif_is_port_alive/1 ]). -export([many_args_100/100]). @@ -75,7 +76,8 @@ all() -> nif_schedule, dirty_nif, dirty_nif_send, dirty_nif_exception, nif_exception, nif_nan_and_inf, nif_atom_too_long, nif_monotonic_time, nif_time_offset, nif_convert_time_unit, - nif_now_time, nif_cpu_time, nif_unique_integer + nif_now_time, nif_cpu_time, nif_unique_integer, + nif_is_process_alive, nif_is_port_alive ]. init_per_testcase(_Case, Config) -> @@ -1939,6 +1941,23 @@ nif_unique_integer(Config) -> true = is_integer(unique_integer_nif([])), true = is_integer(unique_integer_nif([])). +nif_is_process_alive(Config) -> + ensure_lib_loaded(Config), + + {Pid,_} = spawn_monitor(fun() -> receive ok -> nok end end), + true = is_process_alive_nif(Pid), + exit(Pid, die), + receive _ -> ok end, %% Clear monitor + false = is_process_alive_nif(Pid). + +nif_is_port_alive(Config) -> + ensure_lib_loaded(Config), + + Port = open_port({spawn,"/bin/sh -s unix:cmd"},[stderr_to_stdout,eof]), + true = is_port_alive_nif(Port), + port_close(Port), + false = is_port_alive_nif(Port). + %% The NIFs: lib_version() -> undefined. call_history() -> ?nif_stub. @@ -1997,6 +2016,8 @@ call_nif_exception(_) -> ?nif_stub. call_nif_nan_or_inf(_) -> ?nif_stub. call_nif_atom_too_long(_) -> ?nif_stub. unique_integer_nif(_) -> ?nif_stub. +is_process_alive_nif(_) -> ?nif_stub. +is_port_alive_nif(_) -> ?nif_stub. %% maps is_map_nif(_) -> ?nif_stub. diff --git a/erts/emulator/test/nif_SUITE_data/nif_SUITE.c b/erts/emulator/test/nif_SUITE_data/nif_SUITE.c index 1960689590..2ce0168788 100644 --- a/erts/emulator/test/nif_SUITE_data/nif_SUITE.c +++ b/erts/emulator/test/nif_SUITE_data/nif_SUITE.c @@ -30,6 +30,7 @@ static int static_cntA; /* zero by default */ static int static_cntB = NIF_SUITE_LIB_VER * 100; static ERL_NIF_TERM atom_false; +static ERL_NIF_TERM atom_true; static ERL_NIF_TERM atom_self; static ERL_NIF_TERM atom_ok; static ERL_NIF_TERM atom_join; @@ -138,6 +139,7 @@ static int load(ErlNifEnv* env, void** priv_data, ERL_NIF_TERM load_info) msgenv_dtor, ERL_NIF_RT_CREATE, NULL); atom_false = enif_make_atom(env,"false"); + atom_true = enif_make_atom(env,"true"); atom_self = enif_make_atom(env,"self"); atom_ok = enif_make_atom(env,"ok"); atom_join = enif_make_atom(env,"join"); @@ -2008,6 +2010,26 @@ static ERL_NIF_TERM unique_integer(ErlNifEnv* env, int argc, const ERL_NIF_TERM return enif_make_unique_integer(env, properties); } +static ERL_NIF_TERM is_process_alive(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[]) +{ + ErlNifPid pid; + if (!enif_get_local_pid(env, argv[0], &pid)) + return enif_make_badarg(env); + if (enif_is_process_alive(env, &pid)) + return atom_true; + return atom_false; +} + +static ERL_NIF_TERM is_port_alive(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[]) +{ + ErlNifPort port; + if (!enif_get_local_port(env, argv[0], &port)) + return enif_make_badarg(env); + if (enif_is_port_alive(env, &port)) + return atom_true; + return atom_false; +} + static ErlNifFunc nif_funcs[] = { {"lib_version", 0, lib_version}, @@ -2083,7 +2105,9 @@ static ErlNifFunc nif_funcs[] = {"convert_time_unit", 3, convert_time_unit}, {"now_time", 0, now_time}, {"cpu_time", 0, cpu_time}, - {"unique_integer_nif", 1, unique_integer} + {"unique_integer_nif", 1, unique_integer}, + {"is_process_alive_nif", 1, is_process_alive}, + {"is_port_alive_nif", 1, is_port_alive} }; ERL_NIF_INIT(nif_SUITE,nif_funcs,load,reload,upgrade,unload) -- cgit v1.2.3