Add erlang:get/0 and erlang:erase/0

Signed-off-by: Paul Guyot <pguyot@kallisys.net>

Author: pguyot

CHANGELOG.md

@@ -25,6 +25,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Added `erlang:spawn_monitor/1`, `erlang:spawn_monitor/3`
 - Added `lists:dropwhile/2`.
 - Support for `float/1` BIF.
+- Added `erlang:get/0` and `erlang:erase/0`.
 
 ### Fixed
 - ESP32: improved sntp sync speed from a cold boot.

libs/estdlib/src/erlang.erl

@@ -43,8 +43,10 @@
     min/2,
     max/2,
     memory/1,
+    get/0,
     get/1,
     put/2,
+    erase/0,
     erase/1,
     function_exported/3,
     display/1,
@@ -506,6 +508,15 @@ memory(_Type) ->
 monotonic_time(_Unit) ->
     erlang:nif_error(undefined).
 
+%%-----------------------------------------------------------------------------
+%% @returns the process directory
+%% @doc     Return all values from the process dictionary
+%% @end
+%%-----------------------------------------------------------------------------
+-spec get() -> [{any(), any()}].
+get() ->
+    erlang:nif_error(undefined).
+
 %%-----------------------------------------------------------------------------
 %% @param   Key     key in the process dictionary
 %% @returns value associated with this key or undefined
@@ -527,6 +538,15 @@ get(_Key) ->
 put(_Key, _Value) ->
     erlang:nif_error(undefined).
 
+%%-----------------------------------------------------------------------------
+%% @returns the previous process dictionary.
+%% @doc     Erase all keys from the process dictionary.
+%% @end
+%%-----------------------------------------------------------------------------
+-spec erase() -> [{any(), any()}].
+erase() ->
+    erlang:nif_error(undefined).
+
 %%-----------------------------------------------------------------------------
 %% @param   Key     key to erase from the process dictionary
 %% @returns the previous value associated with this key or undefined

src/libAtomVM/nifs.c

@@ -103,6 +103,7 @@ static term nif_erlang_binary_to_list_1(Context *ctx, int argc, term argv[]);
 static term nif_erlang_binary_to_existing_atom_1(Context *ctx, int argc, term argv[]);
 static term nif_erlang_concat_2(Context *ctx, int argc, term argv[]);
 static term nif_erlang_display_1(Context *ctx, int argc, term argv[]);
+static term nif_erlang_erase_0(Context *ctx, int argc, term argv[]);
 static term nif_erlang_erase_1(Context *ctx, int argc, term argv[]);
 static term nif_erlang_error(Context *ctx, int argc, term argv[]);
 static term nif_erlang_exit(Context *ctx, int argc, term argv[]);
@@ -141,6 +142,7 @@ static term nif_erlang_process_flag(Context *ctx, int argc, term argv[]);
 static term nif_erlang_processes(Context *ctx, int argc, term argv[]);
 static term nif_erlang_process_info(Context *ctx, int argc, term argv[]);
 static term nif_erlang_fun_info_2(Context *ctx, int argc, term argv[]);
+static term nif_erlang_get_0(Context *ctx, int argc, term argv[]);
 static term nif_erlang_put_2(Context *ctx, int argc, term argv[]);
 static term nif_erlang_system_info(Context *ctx, int argc, term argv[]);
 static term nif_erlang_system_flag(Context *ctx, int argc, term argv[]);
@@ -309,7 +311,13 @@ static const struct Nif display_nif =
     .nif_ptr = nif_erlang_display_1
 };
 
-static const struct Nif erase_nif =
+static const struct Nif erase_0_nif =
+{
+    .base.type = NIFFunctionType,
+    .nif_ptr = nif_erlang_erase_0
+};
+
+static const struct Nif erase_1_nif =
 {
     .base.type = NIFFunctionType,
     .nif_ptr = nif_erlang_erase_1
@@ -531,6 +539,12 @@ static const struct Nif process_info_nif =
     .nif_ptr = nif_erlang_process_info
 };
 
+static const struct Nif get_0_nif =
+{
+    .base.type = NIFFunctionType,
+    .nif_ptr = nif_erlang_get_0
+};
+
 static const struct Nif put_nif =
 {
     .base.type = NIFFunctionType,
@@ -3646,6 +3660,32 @@ static term nif_erlang_fun_info_2(Context *ctx, int argc, term argv[])
     return fun_info_tuple;
 }
 
+static term nif_erlang_get_0(Context *ctx, int argc, term argv[])
+{
+    UNUSED(argc);
+    UNUSED(argv);
+
+    term result = term_nil();
+    size_t size = 0;
+    struct ListHead *dictionary = &ctx->dictionary;
+    struct ListHead *item;
+    LIST_FOR_EACH (item, dictionary) {
+        size++;
+    }
+    if (UNLIKELY(memory_ensure_free(ctx, LIST_SIZE(size, TUPLE_SIZE(2))) != MEMORY_GC_OK)) {
+        RAISE_ERROR(OUT_OF_MEMORY_ATOM);
+    }
+    LIST_FOR_EACH (item, dictionary) {
+        struct DictEntry *dict_entry = GET_LIST_ENTRY(item, struct DictEntry, head);
+        term tuple = term_alloc_tuple(2, &ctx->heap);
+        term_put_tuple_element(tuple, 0, dict_entry->key);
+        term_put_tuple_element(tuple, 1, dict_entry->value);
+        result = term_list_prepend(tuple, result, &ctx->heap);
+    }
+
+    return result;
+}
+
 static term nif_erlang_put_2(Context *ctx, int argc, term argv[])
 {
     UNUSED(argc);
@@ -3659,6 +3699,19 @@ static term nif_erlang_put_2(Context *ctx, int argc, term argv[])
     return old;
 }
 
+static term nif_erlang_erase_0(Context *ctx, int argc, term argv[])
+{
+    UNUSED(argc);
+
+    term result = nif_erlang_get_0(ctx, argc, argv);
+    if (LIKELY(!term_is_invalid_term(result))) {
+        dictionary_destroy(&ctx->dictionary);
+        list_init(&ctx->dictionary);
+    }
+
+    return result;
+}
+
 static term nif_erlang_erase_1(Context *ctx, int argc, term argv[])
 {
     UNUSED(argc);

src/libAtomVM/nifs.gperf

@@ -50,7 +50,8 @@ erlang:binary_to_integer/2, &binary_to_integer_nif
 erlang:binary_to_list/1, &binary_to_list_nif
 erlang:binary_to_existing_atom/1, &binary_to_existing_atom_1_nif
 erlang:delete_element/2, &delete_element_nif
-erlang:erase/1, &erase_nif
+erlang:erase/0, &erase_0_nif
+erlang:erase/1, &erase_1_nif
 erlang:error/1, &error_nif
 erlang:error/2, &error_nif
 erlang:error/3, &error_nif
@@ -106,6 +107,7 @@ erlang:process_flag/2, &process_flag_nif
 erlang:process_flag/3, &process_flag_nif
 erlang:processes/0, &processes_nif
 erlang:process_info/2, &process_info_nif
+erlang:get/0, &get_0_nif
 erlang:put/2, &put_nif
 erlang:binary_to_term/1, &binary_to_term_nif
 erlang:binary_to_term/2, &binary_to_term_nif

tests/erlang_tests/test_dict.erl

@@ -23,6 +23,7 @@
 -export([start/0, put_int/1, stringize/1, factorial/1, id/1, the_get/1, the_erase/1]).
 
 start() ->
+    ok = test_get_0_erase_0(),
     put_int(0),
     X = put_int(1),
     put_int(2),
@@ -80,3 +81,12 @@ test_put_get_erase() ->
     2 = apply(erlang, list_to_atom("erase"), [{any_term}]),
     undefined = erase({any_term}),
     ok.
+
+test_get_0_erase_0() ->
+    [] = get(),
+    undefined = put({any_term}, 1),
+    [{{any_term}, 1}] = get(),
+    [{{any_term}, 1}] = erase(),
+    [] = get(),
+    [] = erase(),
+    ok.