Merge pull request #1304 from realglobe-Inc/dev/binary-decode_hex

Add functions to load and dump hex string These changes are made under both the "Apache 2.0" and the "GNU Lesser General Public License 2.1 or later" license terms (dual license). SPDX-License-Identifier: Apache-2.0 OR LGPL-2.1-or-later Closes #1287.
atomvm · Oct 11, 2024 · 6f5d064 · 6f5d064
2 parents ff34010 + 11b23ab
commit 6f5d064
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diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -41,6 +41,9 @@ also non string parameters (e.g. `Enum.join([1, 2], ",")`
 [#1100](https://github.com/atomvm/AtomVM/issues/1100)
 - Support for mounting/unmounting storage on ESP32 (such as SD or internal flash) using
 `esp:mount/4` and `esp:umount/1`
+- Support for `binary_to_integer/2`
+- Support for `binary:decode_hex/1` and `binary:encode_hex/1,2`
+- Support for Elixir `Base.decode16/2` and `Base.encode16/2`
 
 ### Changed
 

diff --git a/libs/estdlib/src/binary.erl b/libs/estdlib/src/binary.erl
@@ -2,6 +2,7 @@
 % This file is part of AtomVM.
 %
 % Copyright 2023 Paul Guyot <[email protected]>
+% Copyright 2024 Yuto Oguchi <[email protected]>, Realglobe Inc.
 %
 % Licensed under the Apache License, Version 2.0 (the "License");
 % you may not use this file except in compliance with the License.
@@ -24,7 +25,7 @@
 %%-----------------------------------------------------------------------------
 -module(binary).
 
--export([at/2, part/3, split/2, split/3]).
+-export([at/2, decode_hex/1, encode_hex/1, encode_hex/2, part/3, split/2, split/3]).
 
 %%-----------------------------------------------------------------------------
 %% @param   Binary binary to get a byte from
@@ -37,6 +38,42 @@
 at(_Binary, _Index) ->
     erlang:nif_error(undefined).
 
+%%-----------------------------------------------------------------------------
+%% @param   Data hex encoded binary to decode
+%% @returns decoded binary
+%% @doc     Decodes a hex encoded binary into a binary.
+%% @end
+%%-----------------------------------------------------------------------------
+-spec decode_hex(Data :: <<_:_*16>>) -> binary().
+decode_hex(Data) ->
+    case byte_size(Data) rem 2 of
+        0 -> <<<<(binary_to_integer(B, 16))>> || <<B:2/binary>> <= Data>>;
+        _ -> erlang:error(badarg)
+    end.
+
+%%-----------------------------------------------------------------------------
+%% @param   Data binary data to convert into hex encoded binary
+%% @returns hex encoded binary
+%% @doc     Encodes a binary into a hex encoded binary using the specified case for the hexadecimal digits "a" to "f".
+%% @end
+%%-----------------------------------------------------------------------------
+-spec encode_hex(Data :: binary()) -> binary().
+encode_hex(Data) ->
+    encode_hex(Data, uppercase).
+
+%%-----------------------------------------------------------------------------
+%% @param   Data binary data to convert into hex encoded binary
+%% @param   Case which case to encode into
+%% @returns hex encoded binary
+%% @doc     Encodes a binary into a hex encoded binary using the specified case for the hexadecimal digits "a" to "f".
+%% @end
+%%-----------------------------------------------------------------------------
+-spec encode_hex(Data :: binary(), Case :: lowercase | uppercase) -> binary().
+encode_hex(Data, uppercase) ->
+    <<(integer_to_binary(B, 16)) || <<B:4>> <= Data>>;
+encode_hex(Data, lowercase) ->
+    <<<<(hd(string:to_lower(integer_to_list(B, 16)))):8>> || <<B:4>> <= Data>>.
+
 %%-----------------------------------------------------------------------------
 %% @param   Binary binary to extract a subbinary from
 %% @param   Pos    0-based index of the subbinary to extract

diff --git a/libs/estdlib/src/erlang.erl b/libs/estdlib/src/erlang.erl
@@ -57,6 +57,7 @@
     binary_to_atom/1,
     binary_to_atom/2,
     binary_to_integer/1,
+    binary_to_integer/2,
     binary_to_list/1,
     atom_to_binary/1,
     atom_to_binary/2,
@@ -651,6 +652,16 @@ binary_to_atom(_Binary, _Encoding) ->
 binary_to_integer(_Binary) ->
     erlang:nif_error(undefined).
 
+%%-----------------------------------------------------------------------------
+%% @param   Binary  Binary to parse for integer
+%% @returns the integer represented by the binary
+%% @doc     Parse the text in a given binary as an integer.
+%% @end
+%%-----------------------------------------------------------------------------
+-spec binary_to_integer(Binary :: binary(), Base :: 2..36) -> integer().
+binary_to_integer(_Binary, Base) ->
+    erlang:nif_error(undefined).
+
 %%-----------------------------------------------------------------------------
 %% @param   Binary  Binary to convert to list
 %% @returns a list of bytes from the binary

diff --git a/libs/exavmlib/lib/Base.ex b/libs/exavmlib/lib/Base.ex
@@ -0,0 +1,227 @@
+#
+# This file is part of elixir-lang.
+#
+# Copyright 2014-2023 Elixir Contributors
+# https://github.com/elixir-lang/elixir/commits/v1.17.3/lib/elixir/lib/base.ex
+#
+# Copyright 2024 Yuto Oguchi <[email protected]>, Realglobe Inc.
+#
+# 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
+#
+
+defmodule Base do
+  @moduledoc """
+  This module provides data encoding and decoding functions
+  according to [RFC 4648](https://tools.ietf.org/html/rfc4648).
+
+  This document defines the commonly used base 16, base 32, and base
+  64 encoding schemes.
+
+  ## Base 16 alphabet
+
+  | Value | Encoding | Value | Encoding | Value | Encoding | Value | Encoding |
+  |------:|:---------|------:|:---------|------:|:---------|------:|:---------|
+  |     0 | 0        |     4 | 4        |     8 | 8        |    12 | C        |
+  |     1 | 1        |     5 | 5        |     9 | 9        |    13 | D        |
+  |     2 | 2        |     6 | 6        |    10 | A        |    14 | E        |
+  |     3 | 3        |     7 | 7        |    11 | B        |    15 | F        |
+
+  ## Base 32 alphabet
+
+  | Value | Encoding | Value | Encoding | Value | Encoding | Value | Encoding |
+  |------:|:---------|------:|:---------|------:|:---------|------:|:---------|
+  |     0 | A        |     9 | J        |    18 | S        |    27 | 3        |
+  |     1 | B        |    10 | K        |    19 | T        |    28 | 4        |
+  |     2 | C        |    11 | L        |    20 | U        |    29 | 5        |
+  |     3 | D        |    12 | M        |    21 | V        |    30 | 6        |
+  |     4 | E        |    13 | N        |    22 | W        |    31 | 7        |
+  |     5 | F        |    14 | O        |    23 | X        |       |          |
+  |     6 | G        |    15 | P        |    24 | Y        | (pad) | =        |
+  |     7 | H        |    16 | Q        |    25 | Z        |       |          |
+  |     8 | I        |    17 | R        |    26 | 2        |       |          |
+
+
+  ## Base 32 (extended hex) alphabet
+
+  | Value | Encoding | Value | Encoding | Value | Encoding | Value | Encoding |
+  |------:|:---------|------:|:---------|------:|:---------|------:|:---------|
+  |     0 | 0        |     9 | 9        |    18 | I        |    27 | R        |
+  |     1 | 1        |    10 | A        |    19 | J        |    28 | S        |
+  |     2 | 2        |    11 | B        |    20 | K        |    29 | T        |
+  |     3 | 3        |    12 | C        |    21 | L        |    30 | U        |
+  |     4 | 4        |    13 | D        |    22 | M        |    31 | V        |
+  |     5 | 5        |    14 | E        |    23 | N        |       |          |
+  |     6 | 6        |    15 | F        |    24 | O        | (pad) | =        |
+  |     7 | 7        |    16 | G        |    25 | P        |       |          |
+  |     8 | 8        |    17 | H        |    26 | Q        |       |          |
+
+  ## Base 64 alphabet
+
+  | Value |  Encoding | Value | Encoding | Value | Encoding | Value | Encoding |
+  |------:|:----------|------:|:---------|------:|:---------|------:|:---------|
+  |     0 | A         |    17 | R        |    34 | i        |    51 | z        |
+  |     1 | B         |    18 | S        |    35 | j        |    52 | 0        |
+  |     2 | C         |    19 | T        |    36 | k        |    53 | 1        |
+  |     3 | D         |    20 | U        |    37 | l        |    54 | 2        |
+  |     4 | E         |    21 | V        |    38 | m        |    55 | 3        |
+  |     5 | F         |    22 | W        |    39 | n        |    56 | 4        |
+  |     6 | G         |    23 | X        |    40 | o        |    57 | 5        |
+  |     7 | H         |    24 | Y        |    41 | p        |    58 | 6        |
+  |     8 | I         |    25 | Z        |    42 | q        |    59 | 7        |
+  |     9 | J         |    26 | a        |    43 | r        |    60 | 8        |
+  |    10 | K         |    27 | b        |    44 | s        |    61 | 9        |
+  |    11 | L         |    28 | c        |    45 | t        |    62 | +        |
+  |    12 | M         |    29 | d        |    46 | u        |    63 | /        |
+  |    13 | N         |    30 | e        |    47 | v        |       |          |
+  |    14 | O         |    31 | f        |    48 | w        | (pad) | =        |
+  |    15 | P         |    32 | g        |    49 | x        |       |          |
+  |    16 | Q         |    33 | h        |    50 | y        |       |          |
+
+  ## Base 64 (URL and filename safe) alphabet
+
+  | Value | Encoding | Value | Encoding | Value | Encoding | Value | Encoding |
+  |------:|:---------|------:|:---------|------:|:---------|------:|:---------|
+  |     0 | A        |    17 | R        |    34 | i        |    51 | z        |
+  |     1 | B        |    18 | S        |    35 | j        |    52 | 0        |
+  |     2 | C        |    19 | T        |    36 | k        |    53 | 1        |
+  |     3 | D        |    20 | U        |    37 | l        |    54 | 2        |
+  |     4 | E        |    21 | V        |    38 | m        |    55 | 3        |
+  |     5 | F        |    22 | W        |    39 | n        |    56 | 4        |
+  |     6 | G        |    23 | X        |    40 | o        |    57 | 5        |
+  |     7 | H        |    24 | Y        |    41 | p        |    58 | 6        |
+  |     8 | I        |    25 | Z        |    42 | q        |    59 | 7        |
+  |     9 | J        |    26 | a        |    43 | r        |    60 | 8        |
+  |    10 | K        |    27 | b        |    44 | s        |    61 | 9        |
+  |    11 | L        |    28 | c        |    45 | t        |    62 | -        |
+  |    12 | M        |    29 | d        |    46 | u        |    63 | _        |
+  |    13 | N        |    30 | e        |    47 | v        |       |          |
+  |    14 | O        |    31 | f        |    48 | w        | (pad) | =        |
+  |    15 | P        |    32 | g        |    49 | x        |       |          |
+  |    16 | Q        |    33 | h        |    50 | y        |       |          |
+
+  """
+
+  @type encode_case :: :upper | :lower
+  @type decode_case :: :upper | :lower | :mixed
+
+  @doc """
+  Decodes a base 16 encoded string into a binary string.
+
+  ## Options
+
+  The accepted options are:
+
+    * `:case` - specifies the character case to accept when decoding
+
+  The values for `:case` can be:
+
+    * `:upper` - only allows upper case characters (default)
+    * `:lower` - only allows lower case characters
+    * `:mixed` - allows mixed case characters
+
+  ## Examples
+
+      iex> Base.decode16("666F6F626172")
+      {:ok, "foobar"}
+
+      iex> Base.decode16("666f6f626172", case: :lower)
+      {:ok, "foobar"}
+
+      iex> Base.decode16("666f6F626172", case: :mixed)
+      {:ok, "foobar"}
+
+  """
+  @spec decode16(binary, case: decode_case) :: {:ok, binary} | :error
+  def decode16(string, ops \\ []) do
+    {:ok, decode16!(string, ops)}
+  rescue
+    ArgumentError -> :error
+  end
+
+  @doc """
+  Decodes a base 16 encoded string into a binary string.
+
+  ## Options
+
+  The accepted options are:
+
+    * `:case` - specifies the character case to accept when decoding
+
+  The values for `:case` can be:
+
+    * `:upper` - only allows upper case characters (default)
+    * `:lower` - only allows lower case characters
+    * `:mixed` - allows mixed case characters
+
+  An `ArgumentError` exception is raised if the padding is incorrect or
+  a non-alphabet character is present in the string.
+
+  ## Examples
+
+      iex> Base.decode16!("666F6F626172")
+      "foobar"
+
+      iex> Base.decode16!("666f6f626172", case: :lower)
+      "foobar"
+
+      iex> Base.decode16!("666f6F626172", case: :mixed)
+      "foobar"
+
+  """
+  @spec decode16!(binary, case: decode_case) :: binary
+  def decode16!(string, opts \\ [])
+
+  def decode16!(string, _ops) when is_binary(string) and rem(byte_size(string), 2) == 0 do
+    # TODO: support :case option
+    :binary.decode_hex(string)
+  end
+
+  def decode16!(string, _opts) when is_binary(string) do
+    raise ArgumentError,
+          "string given to decode has wrong length. An even number of bytes was expected, got: #{byte_size(string)}. " <>
+            "Double check your string for unwanted characters or pad it accordingly"
+  end
+
+  @doc """
+  Encodes a binary string into a base 16 encoded string.
+
+  ## Options
+
+  The accepted options are:
+
+    * `:case` - specifies the character case to use when encoding
+
+  The values for `:case` can be:
+
+    * `:upper` - uses upper case characters (default)
+    * `:lower` - uses lower case characters
+
+  ## Examples
+
+      iex> Base.encode16("foobar")
+      "666F6F626172"
+
+      iex> Base.encode16("foobar", case: :lower)
+      "666f6f626172"
+
+  """
+  @spec encode16(binary, case: encode_case) :: binary
+  def encode16(data, opts \\ []) do
+    case Keyword.get(opts, :case, :upper) do
+      :upper -> :binary.encode_hex(data, :uppercase)
+      :lower -> :binary.encode_hex(data, :lowercase)
+    end
+  end
+end
diff --git a/libs/exavmlib/lib/CMakeLists.txt b/libs/exavmlib/lib/CMakeLists.txt
@@ -24,6 +24,7 @@ include(BuildElixir)
 
 set(ELIXIR_MODULES
     AVMPort
+    Base
     Bitwise
     Code
     Console

diff --git a/src/libAtomVM/nifs.c b/src/libAtomVM/nifs.c
@@ -99,7 +99,7 @@ static term nif_erlang_atom_to_binary(Context *ctx, int argc, term argv[]);
 static term nif_erlang_atom_to_list_1(Context *ctx, int argc, term argv[]);
 static term nif_erlang_binary_to_atom_2(Context *ctx, int argc, term argv[]);
 static term nif_erlang_binary_to_float_1(Context *ctx, int argc, term argv[]);
-static term nif_erlang_binary_to_integer_1(Context *ctx, int argc, term argv[]);
+static term nif_erlang_binary_to_integer(Context *ctx, int argc, term argv[]);
 static term nif_erlang_binary_to_list_1(Context *ctx, int argc, term argv[]);
 static term nif_erlang_binary_to_existing_atom_2(Context *ctx, int argc, term argv[]);
 static term nif_erlang_concat_2(Context *ctx, int argc, term argv[]);
@@ -275,7 +275,7 @@ static const struct Nif binary_to_float_nif =
 static const struct Nif binary_to_integer_nif =
 {
     .base.type = NIFFunctionType,
-    .nif_ptr = nif_erlang_binary_to_integer_1
+    .nif_ptr = nif_erlang_binary_to_integer
 };
 
 static const struct Nif binary_to_list_nif =
@@ -1819,10 +1819,8 @@ static term nif_erlang_binary_to_atom_2(Context *ctx, int argc, term argv[])
     return binary_to_atom(ctx, argc, argv, 1);
 }
 
-static term nif_erlang_binary_to_integer_1(Context *ctx, int argc, term argv[])
+static term nif_erlang_binary_to_integer(Context *ctx, int argc, term argv[])
 {
-    UNUSED(argc);
-
     term bin_term = argv[0];
     VALIDATE_VALUE(bin_term, term_is_binary);
 
@@ -1833,14 +1831,26 @@ static term nif_erlang_binary_to_integer_1(Context *ctx, int argc, term argv[])
         RAISE_ERROR(BADARG_ATOM);
     }
 
-    char null_terminated_buf[24];
+    uint8_t base = 10;
+
+    if (argc == 2) {
+        term int_term = argv[1];
+        VALIDATE_VALUE(int_term, term_is_uint8);
+        base = term_to_uint8(int_term);
+    }
+
+    if (UNLIKELY((base < 2) || (base > 36))) {
+        RAISE_ERROR(BADARG_ATOM);
+    }
+
+    char null_terminated_buf[65];
     memcpy(null_terminated_buf, bin_data, bin_data_size);
     null_terminated_buf[bin_data_size] = '\0';
 
-    //TODO: handle 64 bits numbers
     //TODO: handle errors
+    //TODO: do not copy buffer, implement a custom strotoll
     char *endptr;
-    uint64_t value = strtoll(null_terminated_buf, &endptr, 10);
+    uint64_t value = strtoll(null_terminated_buf, &endptr, base);
     if (*endptr != '\0') {
         RAISE_ERROR(BADARG_ATOM);
     }

diff --git a/src/libAtomVM/nifs.gperf b/src/libAtomVM/nifs.gperf
@@ -47,6 +47,7 @@ erlang:binary_to_atom/1, &binary_to_atom_nif
 erlang:binary_to_atom/2, &binary_to_atom_nif
 erlang:binary_to_float/1, &binary_to_float_nif
 erlang:binary_to_integer/1, &binary_to_integer_nif
+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_nif
 erlang:binary_to_existing_atom/2, &binary_to_existing_atom_nif
-Original file line number
+Diff line change
@@ Expand Up / @@ -24,6 +24,7 @@ include(BuildElixir) @@
     set(ELIXIR_MODULES
         AVMPort
+        Base
         Bitwise
         Code
         Console
@@ Expand Down @@