From 884afd8efb8672df2889df98b5b94f3dbb53952c Mon Sep 17 00:00:00 2001 From: Steve Vinoski Date: Mon, 27 Apr 2015 23:39:37 -0400 Subject: Enhance enif_has_pending_exception Sverker Eriksson came up with the following idea: to handle a future ability for NIFs to raise more than just badarg exceptions, modify the recently-added enif_has_pending_exception function to take a second argument: a pointer to ERL_NIF_TERM. If this argument is a null pointer, ignore it. Otherwise, if the first argument, an ErlNifEnv*, has an associated exception, set the pointed-to ERL_NIF_TERM of the second argument to the value of the exception term. Add new tests and documentation for this modification. --- erts/doc/src/erl_nif.xml | 12 +++++++++--- erts/emulator/beam/erl_nif.c | 5 ++++- erts/emulator/beam/erl_nif_api_funcs.h | 2 +- erts/emulator/test/nif_SUITE.erl | 18 ++++++++++-------- erts/emulator/test/nif_SUITE_data/nif_SUITE.c | 25 +++++++++++++++++-------- 5 files changed, 41 insertions(+), 21 deletions(-) (limited to 'erts') diff --git a/erts/doc/src/erl_nif.xml b/erts/doc/src/erl_nif.xml index 4bad8b253c..155aee2f42 100644 --- a/erts/doc/src/erl_nif.xml +++ b/erts/doc/src/erl_nif.xml @@ -778,11 +778,17 @@ typedef enum { and return true, or return false if term is not an unsigned integer or is outside the bounds of type unsigned long.

- intenif_has_pending_exception(ErlNifEnv* env) + intenif_has_pending_exception(ErlNifEnv* env, ERL_NIF_TERM* reason) Check if an exception has been raised.

Return true if a pending exception is associated - with the environment env. The only possible exception is currently - badarg (see enif_make_badarg).

 + with the environment env. If reason is a null pointer, ignore it. + Otherwise, if there's a pending exception associated with env, set the ERL_NIF_TERM + to which reason points to the value of the exception's term. For example, if + enif_make_badarg is called to set a + pending badarg exception, a subsequent call to enif_has_pending_exception(env, &reason) + will set reason to the atom badarg, then return true.

+

See also: enif_make_badarg.

+ intenif_inspect_binary(ErlNifEnv* env, ERL_NIF_TERM bin_term, ErlNifBinary* bin) Inspect the content of a binary diff --git a/erts/emulator/beam/erl_nif.c b/erts/emulator/beam/erl_nif.c index 7876785a76..36da6519f7 100644 --- a/erts/emulator/beam/erl_nif.c +++ b/erts/emulator/beam/erl_nif.c @@ -741,8 +741,11 @@ Eterm enif_make_badarg(ErlNifEnv* env) BIF_ERROR(env->proc, BADARG); } -int enif_has_pending_exception(ErlNifEnv* env) +int enif_has_pending_exception(ErlNifEnv* env, ERL_NIF_TERM* reason) { + if (env->exception_thrown && reason != NULL) { + *reason = am_badarg; + } return env->exception_thrown; } diff --git a/erts/emulator/beam/erl_nif_api_funcs.h b/erts/emulator/beam/erl_nif_api_funcs.h index bdcbb32c46..fe25c803ec 100644 --- a/erts/emulator/beam/erl_nif_api_funcs.h +++ b/erts/emulator/beam/erl_nif_api_funcs.h @@ -156,7 +156,7 @@ ERL_NIF_API_FUNC_DECL(int, enif_map_iterator_next, (ErlNifEnv *env, ErlNifMapIte ERL_NIF_API_FUNC_DECL(int, enif_map_iterator_prev, (ErlNifEnv *env, ErlNifMapIterator *iter)); ERL_NIF_API_FUNC_DECL(int, enif_map_iterator_get_pair, (ErlNifEnv *env, ErlNifMapIterator *iter, ERL_NIF_TERM *key, ERL_NIF_TERM *value)); ERL_NIF_API_FUNC_DECL(ERL_NIF_TERM,enif_schedule_nif,(ErlNifEnv*,const char*,int,ERL_NIF_TERM (*)(ErlNifEnv*,int,const ERL_NIF_TERM[]),int,const ERL_NIF_TERM[])); -ERL_NIF_API_FUNC_DECL(int, enif_has_pending_exception, (ErlNifEnv *env)); +ERL_NIF_API_FUNC_DECL(int, enif_has_pending_exception, (ErlNifEnv *env, ERL_NIF_TERM* reason)); /* ** ADD NEW ENTRIES HERE (before this comment) !!! diff --git a/erts/emulator/test/nif_SUITE.erl b/erts/emulator/test/nif_SUITE.erl index c35c71dd5b..434d1c38d0 100644 --- a/erts/emulator/test/nif_SUITE.erl +++ b/erts/emulator/test/nif_SUITE.erl @@ -1387,7 +1387,7 @@ is_checks(Config) when is_list(Config) -> self(), hd(erlang:ports()), [], [1,9,9,8], {hejsan, "hejsan", [$h,"ejs",<<"an">>]}, -18446744073709551616.2e2), try - ?line error = check_is_exception(), + ?line check_is_exception(), ?line throw(expected_badarg) catch error:badarg -> @@ -1599,9 +1599,9 @@ dirty_nif_exception(Config) when is_list(Config) -> N when is_integer(N) -> ensure_lib_loaded(Config), try - %% this checks that the expected exception - %% occurs when the NIF returns the result - %% of enif_make_badarg directly + %% this checks that the expected exception occurs when the + %% dirty NIF returns the result of enif_make_badarg + %% directly call_dirty_nif_exception(1), ?t:fail(expected_badarg) catch @@ -1611,10 +1611,9 @@ dirty_nif_exception(Config) when is_list(Config) -> ok end, try - %% this checks that the expected exception - %% occurs when the NIF calls enif_make_badarg - %% at some point but then returns a value that - %% isn't an exception + %% this checks that the expected exception occurs when the + %% dirty NIF calls enif_make_badarg at some point but then + %% returns a value that isn't an exception call_dirty_nif_exception(0), ?t:fail(expected_badarg) catch @@ -1631,6 +1630,9 @@ dirty_nif_exception(Config) when is_list(Config) -> nif_exception(Config) when is_list(Config) -> ensure_lib_loaded(Config), try + %% this checks that the expected exception occurs when the NIF + %% calls enif_make_badarg at some point but then tries to return a + %% value that isn't an exception call_nif_exception(), ?t:fail(expected_badarg) catch diff --git a/erts/emulator/test/nif_SUITE_data/nif_SUITE.c b/erts/emulator/test/nif_SUITE_data/nif_SUITE.c index 58d9a9a88c..95e361690f 100644 --- a/erts/emulator/test/nif_SUITE_data/nif_SUITE.c +++ b/erts/emulator/test/nif_SUITE_data/nif_SUITE.c @@ -883,16 +883,19 @@ static ERL_NIF_TERM check_is(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[] * * This function is separate from check_is because it calls enif_make_badarg * and so it must return the badarg exception as its return value. Thus, the - * badarg exception indicates success. Failure is indicated by returning an - * error atom. + * badarg exception indicates success. */ static ERL_NIF_TERM check_is_exception(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[]) { + ERL_NIF_TERM badarg, exc_term; ERL_NIF_TERM error_atom = enif_make_atom(env, "error"); - ERL_NIF_TERM badarg = enif_make_badarg(env); - if (enif_is_exception(env, error_atom)) return error_atom; - if (!enif_is_exception(env, badarg)) return error_atom; - if (!enif_has_pending_exception(env)) return error_atom; + ERL_NIF_TERM badarg_atom = enif_make_atom(env, "badarg"); + assert(!enif_is_exception(env, error_atom)); + badarg = enif_make_badarg(env); + assert(enif_is_exception(env, badarg)); + assert(enif_has_pending_exception(env, NULL)); + assert(enif_has_pending_exception(env, &exc_term)); + assert(enif_is_identical(exc_term, badarg_atom)); return badarg; } @@ -1621,7 +1624,7 @@ static ERL_NIF_TERM call_dirty_nif_exception(ErlNifEnv* env, int argc, const ERL for (i = 1; i < 255; i++) args[i] = enif_make_int(env, i); return enif_schedule_nif(env, "call_dirty_nif_exception", ERL_NIF_DIRTY_JOB_CPU_BOUND, - call_dirty_nif_exception, 255, argv); + call_dirty_nif_exception, 255, args); } case 2: { int return_badarg_directly; @@ -1660,7 +1663,13 @@ static ERL_NIF_TERM call_dirty_nif_zero_args(ErlNifEnv* env, int argc, const ERL */ static ERL_NIF_TERM call_nif_exception(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[]) { + ERL_NIF_TERM exc_term; + ERL_NIF_TERM badarg_atom = enif_make_atom(env, "badarg"); + /* ignore return value */ enif_make_badarg(env); + assert(enif_has_pending_exception(env, NULL)); + assert(enif_has_pending_exception(env, &exc_term)); + assert(enif_is_identical(badarg_atom, exc_term)); return enif_make_atom(env, "ok"); } @@ -1696,7 +1705,7 @@ static ERL_NIF_TERM call_nif_nan_or_inf(ErlNifEnv* env, int argc, const ERL_NIF_ } res = enif_make_double(env, val); assert(enif_is_exception(env, res)); - assert(enif_has_pending_exception(env)); + assert(enif_has_pending_exception(env, NULL)); if (strcmp(arg, "tuple") == 0) { return enif_make_tuple2(env, argv[0], res); } else { -- cgit v1.2.3