sdk/lib/fidl/cpp/roundtrip_test.cc

// Copyright 2018 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

// Check that we can decode things that we can encode.

#include <fidl/test/misc/cpp/fidl.h>
#include <lib/fidl/internal.h>
#include <iostream>
#include "gtest/gtest.h"
#include "lib/fidl/cpp/clone.h"

namespace fidl {
namespace test {
namespace misc {

namespace {

template <class Output, class Input>
Output RoundTrip(const Input& input) {
  const ::fidl::FidlStructField fake_input_interface_fields[] = {
      ::fidl::FidlStructField(Input::FidlType, 16),
  };
  const fidl_type_t fake_input_interface_struct{
      ::fidl::FidlCodedStruct(fake_input_interface_fields, 1,
                              16 + CodingTraits<Input>::encoded_size, "Input")};
  const ::fidl::FidlStructField fake_output_interface_fields[] = {
      ::fidl::FidlStructField(Output::FidlType, 16),
  };
  const fidl_type_t fake_output_interface_struct{::fidl::FidlCodedStruct(
      fake_output_interface_fields, 1, 16 + CodingTraits<Output>::encoded_size,
      "Output")};

  fidl::Encoder enc(0xfefefefe);
  auto ofs = enc.Alloc(CodingTraits<Input>::encoded_size);
  fidl::Clone(input).Encode(&enc, ofs);
  auto msg = enc.GetMessage();

  const char* err_msg = nullptr;
  EXPECT_EQ(ZX_OK, msg.Validate(&fake_input_interface_struct, &err_msg))
      << err_msg;
  EXPECT_EQ(ZX_OK, msg.Decode(&fake_output_interface_struct, &err_msg))
      << err_msg;
  fidl::Decoder dec(std::move(msg));
  Output output;
  Output::Decode(&dec, &output, ofs);
  return output;
}

TEST(SimpleStruct, SerializeAndDeserialize) {
  Int64Struct input{1};
  EXPECT_EQ(input, RoundTrip<Int64Struct>(input));
}

bool cmp_payload(const uint8_t* actual, size_t actual_size,
                 const uint8_t* expected, size_t expected_size) {
  bool pass = true;
  for (size_t i = 0; i < actual_size && i < expected_size; i++) {
    if (actual[i] != expected[i]) {
      pass = false;
      std::cout << std::dec << "element[" << i << "]: " << std::hex
                << "actual=0x" << +actual[i] << " "
                << "expected=0x" << +expected[i] << "\n";
    }
  }
  if (actual_size != expected_size) {
    pass = false;
    std::cout << std::dec << "element[...]: "
              << "actual.size=" << +actual_size << " "
              << "expected.size=" << +expected_size << "\n";
  }
  return pass;
}

template <class Input>
bool ValueToBytes(const Input& input, const std::vector<uint8_t>& expected) {
  fidl::Encoder enc(0xfefefefe);
  auto offset = enc.Alloc(CodingTraits<Input>::encoded_size);
  fidl::Clone(input).Encode(&enc, offset);
  auto msg = enc.GetMessage();
  auto payload = msg.payload();
  return cmp_payload(
      reinterpret_cast<const uint8_t*>(payload.data()), payload.actual(),
      reinterpret_cast<const uint8_t*>(expected.data()), expected.size());
}

TEST(SimpleTable, CheckEmptyTable) {
  SimpleTable input;

  auto expected = std::vector<uint8_t>{
      0,   0,   0,   0,   0,   0,   0,   0,    // max ordinal
      255, 255, 255, 255, 255, 255, 255, 255,  // alloc present
  };

  EXPECT_TRUE(ValueToBytes(input, expected));
}

std::vector<uint8_t> kSimpleTable_X_42_Y_67 = std::vector<uint8_t>{
    5,   0,   0,   0,
    0,   0,   0,   0,  // max ordinal
    255, 255, 255, 255,
    255, 255, 255, 255,  // alloc present
    8,   0,   0,   0,
    0,   0,   0,   0,  // envelope 1: num bytes / num handles
    255, 255, 255, 255,
    255, 255, 255, 255,  // alloc present
    0,   0,   0,   0,
    0,   0,   0,   0,  // envelope 2: num bytes / num handles
    0,   0,   0,   0,
    0,   0,   0,   0,  // no alloc
    0,   0,   0,   0,
    0,   0,   0,   0,  // envelope 3: num bytes / num handles
    0,   0,   0,   0,
    0,   0,   0,   0,  // no alloc
    0,   0,   0,   0,
    0,   0,   0,   0,  // envelope 4: num bytes / num handles
    0,   0,   0,   0,
    0,   0,   0,   0,  // no alloc
    8,   0,   0,   0,
    0,   0,   0,   0,  // envelope 5: num bytes / num handles
    255, 255, 255, 255,
    255, 255, 255, 255,  // alloc present
    42,  0,   0,   0,
    0,   0,   0,   0,  // field X
    67,  0,   0,   0,
    0,   0,   0,   0,  // field Y
};

TEST(SimpleTable, CheckBytesWithXY) {
  SimpleTable input;
  input.set_x(42);
  input.set_y(67);

  EXPECT_TRUE(ValueToBytes(input, kSimpleTable_X_42_Y_67));
}

TEST(SimpleTable, SerializeAndDeserialize) {
  SimpleTable input;
  input.set_x(1);
  EXPECT_EQ(input, RoundTrip<SimpleTable>(input));
  // OlderSimpleTable is an abbreviated ('old') version of SimpleTable:
  // We should be able to decode to it.
  EXPECT_EQ(1, *RoundTrip<OlderSimpleTable>(input).x());
  // NewerSimpleTable is an extended ('new') version of SimpleTable:
  // We should be able to decode to it.
  EXPECT_EQ(1, *RoundTrip<NewerSimpleTable>(input).x());
}

TEST(SimpleTable, SerializeAndDeserializeWithReserved) {
  SimpleTable input;
  input.set_y(1);
  EXPECT_EQ(input, RoundTrip<SimpleTable>(input));
  // OlderSimpleTable is an abbreviated ('old') version of SimpleTable:
  // We should be able to decode to it (but since it doesn't have y,
  // we can't ask for that!)
  EXPECT_FALSE(RoundTrip<OlderSimpleTable>(input).has_x());
  // NewerSimpleTable is an extended ('new') version of SimpleTable:
  // We should be able to decode to it.
  EXPECT_EQ(1, *RoundTrip<NewerSimpleTable>(input).y());
}

TEST(Empty, SerializeAndDeserialize) {
  Empty input{};
  EXPECT_EQ(input, RoundTrip<Empty>(input));
}

TEST(Empty, CheckBytes) {
  Empty input;

  auto expected = std::vector<uint8_t>{
      0,                       // empty struct zero field
         0, 0, 0, 0, 0, 0, 0,  // 7 bytes of padding
  };
  EXPECT_TRUE(ValueToBytes(input, expected));
}

TEST(EmptyStructSandwich, SerializeAndDeserialize) {
  EmptyStructSandwich input{
      .before = "before",
      .after = "after",
  };
  EXPECT_EQ(input, RoundTrip<EmptyStructSandwich>(input));
}

TEST(EmptyStructSandwich, CheckBytes) {
  EmptyStructSandwich input{.before = "before", .after = "after"};

  auto expected = std::vector<uint8_t>{
      6,   0,   0,   0,   0,   0,   0,   0,    // length of "before"
      255, 255, 255, 255, 255, 255, 255, 255,  // "before" is present
      0,                                       // empty struct zero field
           0,   0,   0,   0,   0,   0,   0,    // 7 bytes of padding
      5,   0,   0,   0,   0,   0,   0,   0,    // length of "world"
      255, 255, 255, 255, 255, 255, 255, 255,  // "after" is present
      'b', 'e', 'f', 'o', 'r', 'e',            // "before" string
                                    0,   0,    // 2 bytes of padding
      'a', 'f', 't', 'e', 'r',                 // "after" string
                               0,   0,   0,    // 3 bytes of padding
  };
  EXPECT_TRUE(ValueToBytes(input, expected));
}

TEST(XUnion, Empty) {
  SampleXUnion input;

  auto expected = std::vector<uint8_t>{
      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  // xunion discriminator + padding
      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  // num bytes + num handles
      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  // envelope data is absent
  };
  EXPECT_TRUE(ValueToBytes(input, expected));
}

TEST(XUnion, Int32) {
  SampleXUnion input;
  input.set_i(0xdeadbeef);

  auto expected = std::vector<uint8_t>{
      0xa5, 0x47, 0xdf, 0x29, 0x00, 0x00, 0x00, 0x00,  // xunion discriminator + padding
      0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  // num bytes + num handles
      0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,  // envelope data is present
      0xef, 0xbe, 0xad, 0xde, 0x00, 0x00, 0x00, 0x00,  // envelope content (0xdeadbeef) + padding
  };
  EXPECT_TRUE(ValueToBytes(input, expected));
}

TEST(XUnion, SimpleUnion) {
  SimpleUnion su;
  su.set_str("hello");

  SampleXUnion input;
  input.set_su(std::move(su));

  auto expected = std::vector<uint8_t>{
      0x53, 0x76, 0x31, 0x6f, 0x00, 0x00, 0x00, 0x00,  // xunion discriminator + padding
      0x20, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  // num bytes + num handles
      0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,  // envelope data is present
      // secondary object 0
      0x04, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  // union discriminant + padding
      0x05, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  // string size
      0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,  // string pointer is present
      // secondary object 1
      'h',  'e',  'l',  'l',  'o',  0x00, 0x00, 0x00,  // string: "hello"
  };

  EXPECT_TRUE(ValueToBytes(input, expected));
}

TEST(XUnion, SimpleTable) {
  SimpleTable st;
  st.set_x(42);
  st.set_y(67);

  SampleXUnion input;
  input.set_st(std::move(st));

  auto expected = std::vector<uint8_t>{
      0xdd, 0x2c, 0x65, 0x30, 0x00, 0x00, 0x00, 0x00,  // xunion discriminator + padding
      0x70, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  // num bytes + num handles
      0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,  // envelope data is present
      // <table data follows>
  };
  expected.insert(expected.end(), kSimpleTable_X_42_Y_67.cbegin(),
                  kSimpleTable_X_42_Y_67.cend());

  EXPECT_TRUE(ValueToBytes(input, expected));
}

TEST(XUnion, SerializeAndDeserializeEmpty) {
  SampleXUnion input;

  EXPECT_EQ(input, RoundTrip<SampleXUnion>(input));
}

TEST(XUnion, SerializeAndDeserializeInt32) {
  SampleXUnion input;
  input.set_i(0xdeadbeef);

  EXPECT_EQ(input, RoundTrip<SampleXUnion>(input));
}

TEST(XUnion, SerializeAndDeserializeSimpleUnion) {
  SimpleUnion su;
  su.set_str("hello");

  SampleXUnion input;
  input.set_su(std::move(su));

  EXPECT_EQ(input, RoundTrip<SampleXUnion>(input));
}

TEST(XUnion, SerializeAndDeserializeSimpleTable) {
  SimpleTable st;
  st.set_x(42);
  st.set_y(67);

  SampleXUnion input;
  input.set_st(std::move(st));

  EXPECT_EQ(input, RoundTrip<SampleXUnion>(input));
}

TEST(InlineXUnionInStruct, VerifyWireFormatXUnionIsPresent) {
  SampleXUnion xu;
  xu.set_i(0xdeadbeef);

  InlineXUnionInStruct input;
  input.before = "before";
  input.after = "after";
  input.xu = std::move(xu);

  auto expected = std::vector<uint8_t>{
      0x06, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  // "before" length
      0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,  // "before" presence

      0xa5, 0x47, 0xdf, 0x29, 0x00, 0x00, 0x00, 0x00,  // xunion discriminator + padding
      0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  // num bytes + num handles
      0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,  // envelope data is present

      0x05, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  // "after" length
      0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,  // "before" presence

      // secondary object 1: "before"
      'b',  'e',  'f',  'o',  'r',  'e',  0x00, 0x00,

      // secondary object 2: xunion content
      0xef, 0xbe, 0xad, 0xde, 0x00, 0x00, 0x00, 0x00,  // xunion envelope content (0xdeadbeef) + padding

      // secondary object 3: "after"
      'a',  'f',  't',  'e',  'r',  0x00, 0x00, 0x00,
  };

  EXPECT_TRUE(ValueToBytes(input, expected));
}

TEST(OptionalXUnionInStruct, VerifyWireFormatXUnionIsAbsent) {
  OptionalXUnionInStruct input;
  input.before = "before";
  input.after = "after";

  auto expected = std::vector<uint8_t>{
      0x06, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  // "before" length
      0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,  // "before" presence

      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  // xunion discriminator + padding
      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  // num bytes + num handles
      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  // envelope data is absent

      0x05, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  // "after" length
      0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,  // "before" presence

      // secondary object 1: "before"
      'b',  'e',  'f',  'o',  'r',  'e',  0x00, 0x00,

      // secondary object 2: "after"
      'a',  'f',  't',  'e',  'r',  0x00, 0x00, 0x00,
  };

  EXPECT_TRUE(ValueToBytes(input, expected));
}

TEST(OptionalXUnionInStruct, VerifyWireFormatXUnionIsPresent) {
  auto xu = std::make_unique<SampleXUnion>();
  xu->set_i(0xdeadbeef);

  OptionalXUnionInStruct input;
  input.before = "before";
  input.after = "after";
  input.xu = std::move(xu);

  auto expected = std::vector<uint8_t>{
      0x06, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  // "before" length
      0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,  // "before" presence

      0xa5, 0x47, 0xdf, 0x29, 0x00, 0x00, 0x00, 0x00,  // xunion discriminator + padding
      0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  // num bytes + num handles
      0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,  // envelope data is present

      0x05, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  // "after" length
      0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,  // "before" presence

      // secondary object 1: "before"
      'b',  'e',  'f',  'o',  'r',  'e',  0x00, 0x00,

      // secondary object 2: xunion content
      0xef, 0xbe, 0xad, 0xde, 0x00, 0x00, 0x00, 0x00,  // xunion envelope content (0xdeadbeef) + padding

      // secondary object 3: "after"
      'a',  'f',  't',  'e',  'r',  0x00, 0x00, 0x00,
  };

  EXPECT_TRUE(ValueToBytes(input, expected));
}

TEST(OptionalXUnionInStruct, SerializeAndDeserializeAbsent) {
  OptionalXUnionInStruct input;
  input.before = "before";
  input.after = "after";

  OptionalXUnionInStruct output = RoundTrip<OptionalXUnionInStruct>(input);

  // We cannot byte-wise compare |input| with |output|, since both xunions will
  // have uninitialized memory in their internal xunions, and are not guaranteed
  // to be zeroed.
  EXPECT_EQ(output.xu->Which(), SampleXUnion::Tag::Empty);
}

TEST(OptionalXUnionInStruct, SerializeAndDeserializePresent) {
  auto xu = std::make_unique<SampleXUnion>();
  xu->set_i(0xdeadbeef);

  OptionalXUnionInStruct input;
  input.before = "before";
  input.after = "after";
  input.xu = std::move(xu);

  EXPECT_EQ(input, RoundTrip<OptionalXUnionInStruct>(input));
}

TEST(XUnionInTable, VerifyWireFormatXUnionIsAbsent) {
  XUnionInTable input;
  input.set_before("before");
  input.set_after("after");

  auto expected = std::vector<uint8_t>{
      // primary object
      0x03, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  // vector<envelope> element count
      0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,  // vector<envelope> present

      // secondary object 1: vector data
      // vector[0]: envelope<string before>
      0x18, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  // size + handle count
      0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,  // "before" is present
      // vector[1]: envelope<SampleXUnion xu>
      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  // size + handle count
      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  // xunion is absent
      // vector[2]: envelope<string after>
      0x18, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  // size + handle count
      0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,  // "after" is present

      // secondary object 2: "before" length + pointer
      0x06, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  // "before" length
      0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,  // "before" present

      // secondary object 3: "before"
      'b',  'e',  'f',  'o',  'r',  'e',  0x00, 0x00,  // "before"

      // secondary object 4: "after" length + pointer
      0x05, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  // "after" length
      0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,  // "after" present

      // secondary object 5: "before"
      'a',  'f',  't',  'e',  'r',  0x00, 0x00, 0x00,  // "after"
  };

  EXPECT_TRUE(ValueToBytes(input, expected));
}

TEST(XUnionInTable, VerifyWireFormatXUnionIsPresent) {
  SampleXUnion xu;
  xu.set_i(0xdeadbeef);

  XUnionInTable input;
  input.set_before("before");
  input.set_xu(std::move(xu));
  input.set_after("after");

  auto expected = std::vector<uint8_t>{
      // primary object
      0x03, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  // vector<envelope> element count
      0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,  // vector<envelope> present

      // secondary object 1: vector data
      // vector[0]: envelope<string before>
      0x18, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  // size + handle count
      0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,  // "before" is present
      // vector[1]: envelope<SampleXUnion xu>
      0x20, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  // size + handle count
      0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,  // xunion is present
      // vector[2]: envelope<string after>
      0x18, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  // size + handle count
      0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,  // "after" is present

      // secondary object 2: "before" length + pointer
      0x06, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  // "before" length
      0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,  // "before" present

      // secondary object 3: "before"
      'b',  'e',  'f',  'o',  'r',  'e',  0x00, 0x00,  // "before"

      // secondary object 4: xunion
      0xa5, 0x47, 0xdf, 0x29, 0x00, 0x00, 0x00, 0x00,  // xunion discriminator + padding
      0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  // num bytes + num handles
      0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,  // envelope data is present

      // secondary object 5: xunion content
      0xef, 0xbe, 0xad, 0xde, 0x00, 0x00, 0x00, 0x00,  // 0xdeadbeef + padding

      // secondary object 6: "after" length + pointer
      0x05, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  // "after" length
      0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,  // "after" present

      // secondary object 7: "before"
      'a',  'f',  't',  'e',  'r',  0x00, 0x00, 0x00,  // "after"
  };

  EXPECT_TRUE(ValueToBytes(input, expected));
}

TEST(XUnionInTable, SerializeAndDeserialize) {
  SampleXUnion xu;
  xu.set_i(0xdeadbeef);

  XUnionInTable input;
  input.set_xu(std::move(xu));

  EXPECT_EQ(input, RoundTrip<XUnionInTable>(input));
}

}  // namespace

}  // namespace misc
}  // namespace test
}  // namespace fidl