1 files changed, 217 insertions, 0 deletions
diff --git a/third_party/wasm2c/src/tools/wasm2c.cc b/third_party/wasm2c/src/tools/wasm2c.cc
new file mode 100644
index 0000000000..83e5114af6
--- /dev/null
+++ b/third_party/wasm2c/src/tools/wasm2c.cc
@@ -0,0 +1,217 @@
+/*
+ * Copyright 2017 WebAssembly Community Group participants
+ *
+ * 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.
+ */
+
+#include <cassert>
+#include <cinttypes>
+#include <cstdio>
+#include <cstdlib>
+
+#include "wabt/apply-names.h"
+#include "wabt/binary-reader-ir.h"
+#include "wabt/binary-reader.h"
+#include "wabt/error-formatter.h"
+#include "wabt/feature.h"
+#include "wabt/filenames.h"
+#include "wabt/generate-names.h"
+#include "wabt/ir.h"
+#include "wabt/option-parser.h"
+#include "wabt/result.h"
+#include "wabt/stream.h"
+#include "wabt/validator.h"
+#include "wabt/wast-lexer.h"
+
+#include "wabt/c-writer.h"
+
+using namespace wabt;
+
+static int s_verbose;
+static std::string s_infile;
+static std::string s_outfile;
+static unsigned int s_num_outputs = 1;
+static Features s_features;
+static WriteCOptions s_write_c_options;
+static bool s_read_debug_names = true;
+static std::unique_ptr<FileStream> s_log_stream;
+
+static const char s_description[] =
+    R"(  Read a file in the WebAssembly binary format, and convert it to
+  a C source file and header.
+
+examples:
+  # parse binary file test.wasm and write test.c and test.h
+  $ wasm2c test.wasm -o test.c
+
+  # parse test.wasm, write test.c and test.h, but ignore the debug names, if any
+  $ wasm2c test.wasm --no-debug-names -o test.c
+)";
+
+static const std::string supported_features[] = {
+    "multi-memory", "multi-value", "sign-extension", "saturating-float-to-int",
+    "exceptions",   "memory64",    "extended-const", "simd"};
+
+static bool IsFeatureSupported(const std::string& feature) {
+  return std::find(std::begin(supported_features), std::end(supported_features),
+                   feature) != std::end(supported_features);
+};
+
+static void ParseOptions(int argc, char** argv) {
+  OptionParser parser("wasm2c", s_description);
+
+  parser.AddOption('v', "verbose", "Use multiple times for more info", []() {
+    s_verbose++;
+    s_log_stream = FileStream::CreateStderr();
+  });
+  parser.AddOption(
+      'o', "output", "FILENAME",
+      "Output file for the generated C source file, by default use stdout",
+      [](const char* argument) {
+        s_outfile = argument;
+        ConvertBackslashToSlash(&s_outfile);
+      });
+  parser.AddOption(
+      '\0', "num-outputs", "NUM", "Number of output files to write",
+      [](const char* argument) { s_num_outputs = atoi(argument); });
+  parser.AddOption(
+      'n', "module-name", "MODNAME",
+      "Unique name for the module being generated. This name is prefixed to\n"
+      "each of the generaed C symbols. By default, the module name from the\n"
+      "names section is used. If that is not present the name of the input\n"
+      "file is used as the default.\n",
+      [](const char* argument) { s_write_c_options.module_name = argument; });
+  s_features.AddOptions(&parser);
+  parser.AddOption("no-debug-names", "Ignore debug names in the binary file",
+                   []() { s_read_debug_names = false; });
+  parser.AddArgument("filename", OptionParser::ArgumentCount::One,
+                     [](const char* argument) {
+                       s_infile = argument;
+                       ConvertBackslashToSlash(&s_infile);
+                     });
+  parser.Parse(argc, argv);
+  s_write_c_options.features = &s_features;
+
+  bool any_non_supported_feature = false;
+#define WABT_FEATURE(variable, flag, default_, help)   \
+  any_non_supported_feature |=                         \
+      (s_features.variable##_enabled() != default_) && \
+      s_features.variable##_enabled() && !IsFeatureSupported(flag);
+#include "wabt/feature.def"
+#undef WABT_FEATURE
+
+  if (any_non_supported_feature) {
+    fprintf(stderr,
+            "wasm2c currently only supports a limited set of features.\n");
+    exit(1);
+  }
+}
+
+// TODO(binji): copied from binary-writer-spec.cc, probably should share.
+static std::string_view strip_extension(std::string_view s) {
+  std::string_view ext = s.substr(s.find_last_of('.'));
+  std::string_view result = s;
+
+  if (ext == ".c")
+    result.remove_suffix(ext.length());
+  return result;
+}
+
+Result Wasm2cMain(Errors& errors) {
+  if (s_num_outputs < 1) {
+    fprintf(stderr, "Number of output files must be positive.\n");
+    return Result::Error;
+  }
+
+  std::vector<uint8_t> file_data;
+  CHECK_RESULT(ReadFile(s_infile.c_str(), &file_data));
+
+  Module module;
+  const bool kStopOnFirstError = true;
+  const bool kFailOnCustomSectionError = true;
+  ReadBinaryOptions options(s_features, s_log_stream.get(), s_read_debug_names,
+                            kStopOnFirstError, kFailOnCustomSectionError);
+  CHECK_RESULT(ReadBinaryIr(s_infile.c_str(), file_data.data(),
+                            file_data.size(), options, &errors, &module));
+  CHECK_RESULT(ValidateModule(&module, &errors, s_features));
+  CHECK_RESULT(GenerateNames(&module));
+  /* TODO(binji): This shouldn't fail; if a name can't be applied
+   * (because the index is invalid, say) it should just be skipped. */
+  ApplyNames(&module);
+
+  if (!s_outfile.empty()) {
+    std::string header_name_full =
+        std::string(strip_extension(s_outfile)) + ".h";
+    std::vector<FileStream> c_streams;
+    if (s_num_outputs == 1) {
+      c_streams.emplace_back(s_outfile.c_str());
+    } else {
+      std::string output_prefix{strip_extension(s_outfile)};
+      for (unsigned int i = 0; i < s_num_outputs; i++) {
+        c_streams.emplace_back(output_prefix + "_" + std::to_string(i) + ".c");
+      }
+    }
+    std::vector<Stream*> c_stream_ptrs;
+    for (auto& s : c_streams) {
+      c_stream_ptrs.emplace_back(&s);
+    }
+    FileStream h_stream(header_name_full);
+    std::string_view header_name = GetBasename(header_name_full);
+    if (s_write_c_options.module_name.empty()) {
+      s_write_c_options.module_name = module.name;
+      if (s_write_c_options.module_name.empty()) {
+        // In the absence of module name in the names section use the filename.
+        s_write_c_options.module_name = StripExtension(GetBasename(s_infile));
+      }
+    }
+    if (s_num_outputs == 1) {
+      CHECK_RESULT(WriteC(std::move(c_stream_ptrs), &h_stream, c_stream_ptrs[0],
+                          std::string(header_name).c_str(), "", &module,
+                          s_write_c_options));
+    } else {
+      std::string header_impl_name_full =
+          std::string(strip_extension(s_outfile)) + "-impl.h";
+      FileStream h_impl_stream(header_impl_name_full);
+      std::string_view header_impl_name = GetBasename(header_impl_name_full);
+      CHECK_RESULT(WriteC(std::move(c_stream_ptrs), &h_stream, &h_impl_stream,
+                          std::string(header_name).c_str(),
+                          std::string(header_impl_name).c_str(), &module,
+                          s_write_c_options));
+    }
+  } else {
+    FileStream stream(stdout);
+    CHECK_RESULT(WriteC({&stream}, &stream, &stream, "wasm.h", "", &module,
+                        s_write_c_options));
+  }
+
+  return Result::Ok;
+}
+
+int ProgramMain(int argc, char** argv) {
+  Result result;
+
+  InitStdio();
+  ParseOptions(argc, argv);
+
+  Errors errors;
+  result = Wasm2cMain(errors);
+  FormatErrorsToFile(errors, Location::Type::Binary);
+
+  return result != Result::Ok;
+}
+
+int main(int argc, char** argv) {
+  WABT_TRY
+  return ProgramMain(argc, argv);
+  WABT_CATCH_BAD_ALLOC_AND_EXIT
+}