Fix encoding of integers with units

Signed-off-by: Paul Guyot <[email protected]>

Author: pguyot

src/libAtomVM/bitstring.c

@@ -63,9 +63,14 @@ bool bitstring_insert_any_integer(uint8_t *dst, avm_int_t offset, avm_int64_t va
     if (bs_flags != 0) {
         return false;
     }
+    // value is truncated to 64 bits
+    if (n > 8 * sizeof(value)) {
+        offset += n - (8 * sizeof(value));
+        n = 8 * sizeof(value);
+    }
     for (int i = 0; i < n; ++i) {
         int k = (n - 1) - i;
-        int bit_val = (value & (0x01 << k)) >> k;
+        int bit_val = (value & (0x01LL << k)) >> k;
         if (bit_val) {
             int bit_pos = offset + i;
             int byte_pos = bit_pos >> 3; // div 8

src/libAtomVM/opcodesswitch.h

@@ -3643,14 +3643,10 @@ static bool maybe_call_native(Context *ctx, AtomString module_name, AtomString f
 
                     avm_int64_t src_value = term_maybe_unbox_int64(src);
                     avm_int_t size_value = term_to_int(size);
-                    if (unit != 1) {
-                        TRACE("bs_put_integer: unit is not 1\n");
-                        RAISE_ERROR(UNSUPPORTED_ATOM);
-                    }
 
                     TRACE("bs_put_integer/5, fail=%u size=%li unit=%u flags=%x src=%i\n", (unsigned) fail, size_value, (unsigned) unit, (int) flags_value, (unsigned int) src_value);
 
-                    bool result = bitstring_insert_integer(ctx->bs, ctx->bs_offset, src_value, size_value, flags_value);
+                    bool result = bitstring_insert_integer(ctx->bs, ctx->bs_offset, src_value, size_value * unit, flags_value);
                     if (UNLIKELY(!result)) {
                         TRACE("bs_put_integer: Failed to insert integer into binary\n");
                         RAISE_ERROR(BADARG_ATOM);

tests/erlang_tests/test_bs.erl

@@ -36,7 +36,7 @@ start() ->
 
     ok = test_create_with_invalid_int_value(),
     ok = test_create_with_invalid_int_size(),
-    ok = test_create_with_unsupported_int_unit(),
+    ok = test_create_with_int_unit(),
     ok = test_create_with_unsupported_unaligned_int_size(),
     ok = test_create_with_int_little_endian(),
     ok = test_create_with_int_signed(),
@@ -119,8 +119,14 @@ test_create_with_invalid_int_value() ->
 test_create_with_invalid_int_size() ->
     expect_error(fun() -> create_int_binary(16#F, id(bar)) end, badarg).
 
-test_create_with_unsupported_int_unit() ->
-    atom_unsupported(fun() -> create_int_binary_unit_3(16#F, id(32)) end).
+test_create_with_int_unit() ->
+    <<1, 66, 67>> = create_int_binary_unit_3(16#14243, id(8)),
+    <<0, 0, 0, 1, 66, 67>> = create_int_binary_unit_3(16#14243, id(16)),
+    <<0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 15>> = create_int_binary_unit_3(16#F, id(32)),
+    <<0, 0, 0, 0, 16#12, 16#34, 16#56, 16#78, 16#90, 16#AB, 16#CD, 16#EF>> = create_int_binary_unit_3(
+        16#1234567890ABCDEF, id(32)
+    ),
+    ok.
 
 test_create_with_unsupported_unaligned_int_size() ->
     atom_unsupported(fun() -> create_int_binary(16#FFFF, id(28)) end).