Add support for binary:copy/1,2

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

Author: pguyot

CHANGELOG.md

@@ -29,6 +29,7 @@ also non string parameters (e.g. `Enum.join([1, 2], ",")`
 - Add support to Elixir for `Keyword.split/2`
 - Support for `binary:split/3` and `string:find/2,3`
 - Support for large tuples (more than 255 elements) in external terms.
+- Support for `binary:copy/1,2`
 
 ### Changed
 

src/libAtomVM/nifs.c

@@ -88,6 +88,7 @@ static term binary_to_atom(Context *ctx, int argc, term argv[], int create_new);
 static term list_to_atom(Context *ctx, int argc, term argv[], int create_new);
 
 static term nif_binary_at_2(Context *ctx, int argc, term argv[]);
+static term nif_binary_copy(Context *ctx, int argc, term argv[]);
 static term nif_binary_first_1(Context *ctx, int argc, term argv[]);
 static term nif_binary_last_1(Context *ctx, int argc, term argv[]);
 static term nif_binary_part_3(Context *ctx, int argc, term argv[]);
@@ -211,6 +212,12 @@ static const struct Nif binary_at_nif =
     .nif_ptr = nif_binary_at_2
 };
 
+static const struct Nif binary_copy_nif =
+{
+    .base.type = NIFFunctionType,
+    .nif_ptr = nif_binary_copy
+};
+
 static const struct Nif binary_first_nif =
 {
     .base.type = NIFFunctionType,
@@ -2943,6 +2950,37 @@ static term nif_binary_at_2(Context *ctx, int argc, term argv[])
     return term_from_int11(term_binary_data(bin_term)[pos]);
 }
 
+static term nif_binary_copy(Context *ctx, int argc, term argv[])
+{
+    term bin_term = argv[0];
+    VALIDATE_VALUE(bin_term, term_is_binary);
+
+    size_t count = 1;
+
+    if (argc == 2) {
+        term count_term = argv[1];
+        VALIDATE_VALUE(count_term, term_is_integer);
+        count = term_to_int(count_term);
+    }
+
+    size_t size = term_binary_size(bin_term);
+    size_t dest_size = size * count;
+
+    size_t alloc_heap_size = term_binary_heap_size(dest_size);
+    if (UNLIKELY(memory_ensure_free_with_roots(ctx, alloc_heap_size, 1, &bin_term, MEMORY_CAN_SHRINK) != MEMORY_GC_OK)) {
+        RAISE_ERROR(OUT_OF_MEMORY_ATOM);
+    }
+
+    term result = term_create_uninitialized_binary(dest_size, &ctx->heap, ctx->global);
+    uint8_t *dest = (uint8_t *) term_binary_data(result);
+    const void *src = (const void *) term_binary_data(bin_term);
+    for (size_t i = 0; i < count; i++) {
+        memcpy((void *) dest, src, size);
+        dest += size;
+    }
+    return result;
+}
+
 static term nif_binary_first_1(Context *ctx, int argc, term argv[])
 {
     UNUSED(argc);

src/libAtomVM/nifs.gperf

@@ -32,6 +32,8 @@ struct NifNameAndNifPtr
 };
 %%
 binary:at/2, &binary_at_nif
+binary:copy/1, &binary_copy_nif
+binary:copy/2, &binary_copy_nif
 binary:first/1, &binary_first_nif
 binary:last/1, &binary_last_nif
 binary:part/3, &binary_part_nif

tests/erlang_tests/CMakeLists.txt

@@ -267,6 +267,7 @@ compile_erlang(spawn_fun3)
 compile_erlang(binary_at_test)
 compile_erlang(binary_first_test)
 compile_erlang(binary_last_test)
+compile_erlang(test_binary_copy)
 
 compile_erlang(test_integer_to_binary)
 compile_erlang(test_list_to_binary)
@@ -736,6 +737,7 @@ add_custom_target(erlang_test_modules DEPENDS
     binary_at_test.beam
     binary_first_test.beam
     binary_last_test.beam
+    test_binary_copy.beam
 
     test_integer_to_binary.beam
     test_list_to_binary.beam

tests/erlang_tests/test_binary_copy.erl

@@ -0,0 +1,40 @@
+%
+% This file is part of AtomVM.
+%
+% Copyright 2024 Paul Guyot <pguyot@kallisys.net>
+%
+% Licensed under the Apache License, Version 2.0 (the "License");
+% you may not use this file except in compliance with the License.
+% You may obtain a copy of the License at
+%
+%    http://www.apache.org/licenses/LICENSE-2.0
+%
+% Unless required by applicable law or agreed to in writing, software
+% distributed under the License is distributed on an "AS IS" BASIS,
+% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+% See the License for the specific language governing permissions and
+% limitations under the License.
+%
+% SPDX-License-Identifier: Apache-2.0 OR LGPL-2.1-or-later
+%
+
+-module(test_binary_copy).
+
+-export([start/0]).
+
+start() ->
+    ok = test_copy1(),
+    ok = test_copy2(),
+    0.
+
+test_copy1() ->
+    <<>> = binary:copy(<<>>),
+    <<"foo">> = binary:copy(<<"foo">>),
+    ok.
+
+test_copy2() ->
+    <<>> = binary:copy(<<>>, 1),
+    <<"foo">> = binary:copy(<<"foo">>, 1),
+    <<>> = binary:copy(<<"foo">>, 0),
+    <<"foofoo">> = binary:copy(<<"foo">>, 2),
+    ok.

tests/test.c

@@ -309,6 +309,7 @@ struct Test tests[] = {
     TEST_CASE_EXPECTED(binary_at_test, 121),
     TEST_CASE_EXPECTED(binary_first_test, 82),
     TEST_CASE_EXPECTED(binary_last_test, 110),
+    TEST_CASE(test_binary_copy),
 
     TEST_CASE(test_integer_to_binary),
     TEST_CASE(test_list_to_binary),