From f951b3fcc69c195ce04ae1022fa53272cb74f71b Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?John=20H=C3=B6gberg?= Date: Wed, 6 Mar 2019 15:28:30 +0100 Subject: erts: Add enif_term_type This helps avoid long sequences of enif_is_xxx in code that serializes terms (such as JSON encoders) by letting the user switch on the type. --- erts/doc/src/erl_nif.xml | 42 ++++++++++++++++++++++++++ erts/emulator/beam/erl_nif.c | 41 +++++++++++++++++++++++++ erts/emulator/beam/erl_nif.h | 23 +++++++++++++- erts/emulator/beam/erl_nif_api_funcs.h | 3 ++ erts/emulator/test/nif_SUITE.erl | 43 +++++++++++++++++++++++++-- erts/emulator/test/nif_SUITE_data/nif_SUITE.c | 33 +++++++++++++++++++- 6 files changed, 181 insertions(+), 4 deletions(-) diff --git a/erts/doc/src/erl_nif.xml b/erts/doc/src/erl_nif.xml index cc7452bab5..cf1994887a 100644 --- a/erts/doc/src/erl_nif.xml +++ b/erts/doc/src/erl_nif.xml @@ -3368,6 +3368,48 @@ if (retval & ERL_NIF_SELECT_STOP_CALLED) { + + ErlNifTermType + enif_term_type(ErlNifEnv *env, ERL_NIF_TERM term) + + Determine the type of a term. + +

Determines the type of the given term. The term must be an ordinary + Erlang term and not one of the special terms returned by + + enif_raise_exception, + + enif_schedule_nif, or similar.

+

The following types are defined at the moment:

+ + ERL_NIF_TERM_TYPE_ATOM + + ERL_NIF_TERM_TYPE_BITSTRING +

A bitstring or binary

 + ERL_NIF_TERM_TYPE_FLOAT + + ERL_NIF_TERM_TYPE_FUN + + ERL_NIF_TERM_TYPE_INTEGER + + ERL_NIF_TERM_TYPE_LIST +

A list, empty or not

 + ERL_NIF_TERM_TYPE_MAP + + ERL_NIF_TERM_TYPE_PID + + ERL_NIF_TERM_TYPE_PORT + + ERL_NIF_TERM_TYPE_REFERENCE + + ERL_NIF_TERM_TYPE_TUPLE + + +

Note that new types may be added in the future, so the caller must + be prepared to handle unknown types.

+ + + int enif_thread_create(char *name,ErlNifTid diff --git a/erts/emulator/beam/erl_nif.c b/erts/emulator/beam/erl_nif.c index 349d9bf13a..dd9210a888 100644 --- a/erts/emulator/beam/erl_nif.c +++ b/erts/emulator/beam/erl_nif.c @@ -1158,6 +1158,47 @@ int enif_is_number(ErlNifEnv* env, ERL_NIF_TERM term) return is_number(term); } +ErlNifTermType enif_term_type(ErlNifEnv* env, ERL_NIF_TERM term) { + (void)env; + + switch (tag_val_def(term)) { + case ATOM_DEF: + return ERL_NIF_TERM_TYPE_ATOM; + case BINARY_DEF: + return ERL_NIF_TERM_TYPE_BITSTRING; + case FLOAT_DEF: + return ERL_NIF_TERM_TYPE_FLOAT; + case EXPORT_DEF: + case FUN_DEF: + return ERL_NIF_TERM_TYPE_FUN; + case BIG_DEF: + case SMALL_DEF: + return ERL_NIF_TERM_TYPE_INTEGER; + case LIST_DEF: + case NIL_DEF: + return ERL_NIF_TERM_TYPE_LIST; + case MAP_DEF: + return ERL_NIF_TERM_TYPE_MAP; + case EXTERNAL_PID_DEF: + case PID_DEF: + return ERL_NIF_TERM_TYPE_PID; + case EXTERNAL_PORT_DEF: + case PORT_DEF: + return ERL_NIF_TERM_TYPE_PORT; + case EXTERNAL_REF_DEF: + case REF_DEF: + return ERL_NIF_TERM_TYPE_REFERENCE; + case TUPLE_DEF: + return ERL_NIF_TERM_TYPE_TUPLE; + default: + /* tag_val_def() aborts on its own when passed complete garbage, but + * it's possible that the user has given us garbage that just happens + * to match something that tag_val_def() accepts but we don't, like + * binary match contexts. */ + ERTS_INTERNAL_ERROR("Invalid term passed to enif_term_type"); + } +} + static void aligned_binary_dtor(struct enif_tmp_obj_t* obj) { erts_free_aligned_binary_bytes_extra((byte*)obj, obj->allocator); diff --git a/erts/emulator/beam/erl_nif.h b/erts/emulator/beam/erl_nif.h index 3fd1a8fd4c..a599511c78 100644 --- a/erts/emulator/beam/erl_nif.h +++ b/erts/emulator/beam/erl_nif.h @@ -55,6 +55,7 @@ ** 2.14: 21.0 add enif_ioq_peek_head, enif_(mutex|cond|rwlock|thread)_name ** enif_vfprintf, enif_vsnprintf, enif_make_map_from_arrays ** 2.15: 22.0 ERL_NIF_SELECT_CANCEL, enif_select_(read|write) +** enif_term_type */ #define ERL_NIF_MAJOR_VERSION 2 #define ERL_NIF_MINOR_VERSION 15 @@ -63,7 +64,7 @@ * with ticket syntax like "erts-@OTP-12345@", or a temporary placeholder * between two @ like "erts-@MyName@", if you don't know what a ticket is. */ -#define ERL_NIF_MIN_ERTS_VERSION "erts-@OTP-15095@ (OTP-22)" +#define ERL_NIF_MIN_ERTS_VERSION "erts-@OTP-15095 OTP-15640@ (OTP-22)" /* * The emulator will refuse to load a nif-lib with a major version @@ -282,6 +283,26 @@ typedef enum { ERL_NIF_IOQ_NORMAL = 1 } ErlNifIOQueueOpts; +typedef enum { + ERL_NIF_TERM_TYPE_ATOM = 1, + ERL_NIF_TERM_TYPE_BITSTRING = 2, + ERL_NIF_TERM_TYPE_FLOAT = 3, + ERL_NIF_TERM_TYPE_FUN = 4, + ERL_NIF_TERM_TYPE_INTEGER = 5, + ERL_NIF_TERM_TYPE_LIST = 6, + ERL_NIF_TERM_TYPE_MAP = 7, + ERL_NIF_TERM_TYPE_PID = 8, + ERL_NIF_TERM_TYPE_PORT = 9, + ERL_NIF_TERM_TYPE_REFERENCE = 10, + ERL_NIF_TERM_TYPE_TUPLE = 11, + + /* This is a dummy value intended to coax the compiler into warning about + * unhandled values in a switch even if all the above values have been + * handled. We can add new entries at any time so the user must always + * have a default case. */ + ERL_NIF_TERM_TYPE__MISSING_DEFAULT_CASE__READ_THE_MANUAL = -1 +} ErlNifTermType; + /* * Return values from enif_thread_type(). Negative values * reserved for specific types of non-scheduler threads. diff --git a/erts/emulator/beam/erl_nif_api_funcs.h b/erts/emulator/beam/erl_nif_api_funcs.h index 8ab454c8dd..d57f6ec97c 100644 --- a/erts/emulator/beam/erl_nif_api_funcs.h +++ b/erts/emulator/beam/erl_nif_api_funcs.h @@ -215,6 +215,8 @@ ERL_NIF_API_FUNC_DECL(ERL_NIF_TERM,enif_make_monitor_term,(ErlNifEnv* env, const ERL_NIF_API_FUNC_DECL(void,enif_set_pid_undefined,(ErlNifPid* pid)); ERL_NIF_API_FUNC_DECL(int,enif_is_pid_undefined,(const ErlNifPid* pid)); +ERL_NIF_API_FUNC_DECL(ErlNifTermType,enif_term_type,(ErlNifEnv* env, ERL_NIF_TERM term)); + /* ** ADD NEW ENTRIES HERE (before this comment) !!! */ @@ -401,6 +403,7 @@ ERL_NIF_API_FUNC_DECL(int,enif_is_pid_undefined,(const ErlNifPid* pid)); # define enif_make_monitor_term ERL_NIF_API_FUNC_MACRO(enif_make_monitor_term) # define enif_set_pid_undefined ERL_NIF_API_FUNC_MACRO(enif_set_pid_undefined) # define enif_is_pid_undefined ERL_NIF_API_FUNC_MACRO(enif_is_pid_undefined) +# define enif_term_type ERL_NIF_API_FUNC_MACRO(enif_term_type) /* ** ADD NEW ENTRIES HERE (before this comment) diff --git a/erts/emulator/test/nif_SUITE.erl b/erts/emulator/test/nif_SUITE.erl index 4a0ad9c1d5..2309f844b9 100644 --- a/erts/emulator/test/nif_SUITE.erl +++ b/erts/emulator/test/nif_SUITE.erl @@ -65,7 +65,8 @@ nif_whereis/1, nif_whereis_parallel/1, nif_whereis_threaded/1, nif_whereis_proxy/1, nif_ioq/1, - pid/1 + pid/1, + nif_term_type/1 ]). -export([many_args_100/100]). @@ -105,7 +106,8 @@ all() -> nif_phash2, nif_whereis, nif_whereis_parallel, nif_whereis_threaded, nif_ioq, - pid]. + pid, + nif_term_type]. groups() -> [{G, [], api_repeaters()} || G <- api_groups()] @@ -3392,6 +3394,41 @@ pid(Config) -> {false, _} = get_local_pid_nif(undefined), ok. +nif_term_type(Config) -> + ensure_lib_loaded(Config), + + atom = term_type_nif(atom), + + bitstring = term_type_nif(<<1:1>>), + bitstring = term_type_nif(<<1:8>>), + + float = term_type_nif(0.0), + + 'fun' = term_type_nif(fun external:function/1), + 'fun' = term_type_nif(fun(A) -> A end), + 'fun' = term_type_nif(fun id/1), + + integer = term_type_nif(1 bsl 1024), %Bignum. + integer = term_type_nif(1), + + list = term_type_nif([list]), + list = term_type_nif([]), + + LargeMap = maps:from_list([{N, N} || N <- lists:seq(1, 256)]), + map = term_type_nif(LargeMap), + map = term_type_nif(#{ small => map }), + + pid = term_type_nif(self()), + + Port = open_port({spawn,echo_drv},[eof]), + port = term_type_nif(Port), + port_close(Port), + + reference = term_type_nif(make_ref()), + + tuple = term_type_nif({}), + + ok. id(I) -> I. @@ -3507,5 +3544,7 @@ set_pid_undefined_nif() -> ?nif_stub. is_pid_undefined_nif(_) -> ?nif_stub. compare_pids_nif(_, _) -> ?nif_stub. +term_type_nif(_) -> ?nif_stub. + nif_stub_error(Line) -> exit({nif_not_loaded,module,?MODULE,line,Line}). diff --git a/erts/emulator/test/nif_SUITE_data/nif_SUITE.c b/erts/emulator/test/nif_SUITE_data/nif_SUITE.c index 0d5d900d31..1906384af4 100644 --- a/erts/emulator/test/nif_SUITE_data/nif_SUITE.c +++ b/erts/emulator/test/nif_SUITE_data/nif_SUITE.c @@ -3583,6 +3583,36 @@ static ERL_NIF_TERM compare_pids_nif(ErlNifEnv* env, int argc, const ERL_NIF_TER return enif_make_int(env, enif_compare_pids(&a, &b)); } +static ERL_NIF_TERM term_type_nif(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[]) +{ + switch (enif_term_type(env, argv[0])) { + case ERL_NIF_TERM_TYPE_ATOM: + return enif_make_atom(env, "atom"); + case ERL_NIF_TERM_TYPE_BITSTRING: + return enif_make_atom(env, "bitstring"); + case ERL_NIF_TERM_TYPE_FLOAT: + return enif_make_atom(env, "float"); + case ERL_NIF_TERM_TYPE_FUN: + return enif_make_atom(env, "fun"); + case ERL_NIF_TERM_TYPE_INTEGER: + return enif_make_atom(env, "integer"); + case ERL_NIF_TERM_TYPE_LIST: + return enif_make_atom(env, "list"); + case ERL_NIF_TERM_TYPE_MAP: + return enif_make_atom(env, "map"); + case ERL_NIF_TERM_TYPE_PID: + return enif_make_atom(env, "pid"); + case ERL_NIF_TERM_TYPE_PORT: + return enif_make_atom(env, "port"); + case ERL_NIF_TERM_TYPE_REFERENCE: + return enif_make_atom(env, "reference"); + case ERL_NIF_TERM_TYPE_TUPLE: + return enif_make_atom(env, "tuple"); + default: + return enif_make_badarg(env); + } +} + static ErlNifFunc nif_funcs[] = { {"lib_version", 0, lib_version}, @@ -3690,7 +3720,8 @@ static ErlNifFunc nif_funcs[] = {"make_pid_nif", 1, make_pid_nif}, {"set_pid_undefined_nif", 0, set_pid_undefined_nif}, {"is_pid_undefined_nif", 1, is_pid_undefined_nif}, - {"compare_pids_nif", 2, compare_pids_nif} + {"compare_pids_nif", 2, compare_pids_nif}, + {"term_type_nif", 1, term_type_nif} }; ERL_NIF_INIT(nif_SUITE,nif_funcs,load,NULL,upgrade,unload) -- cgit v1.2.3