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/*
* 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
*
*
* 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);
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
}