asmjspack.cpp

// vim: set ts=2 sw=2 tw=99 et:

#include "pack.h"
#include "unpack.h"

#include <stdexcept>
#include <iostream>
#include <fstream>
#include <vector>

using namespace std;

int
main(int argc, char** argv)
try
{
  if (argc != 3 || !argv[1] || !argv[2]) {
    cerr << "Usage: asmjspack in.js out.asm" << endl;
    return -1;
  }

  // Parse the asm.js file.
  ifstream in_stream(argv[1], ios::binary | ios::ate);
  in_stream.exceptions(ios::failbit | ios::badbit);
  vector<char> in_bytes(in_stream.tellg());
  in_stream.seekg(0);
  in_stream.read(in_bytes.data(), in_bytes.size());
  in_bytes.push_back('\0');
  in_stream.close();
  const asmjs::FuncNode& module = asmjs::parse(in_bytes.data());

  // Write out the .asm file (with bogus unpacked-size).
  fstream out_stream(argv[2], ios::in | ios::out | ios::binary | ios::trunc);
  out_stream.exceptions(ios::failbit | ios::badbit);
  asmjs::pack(out_stream, module);

  // Compute unpacked-size (using unpack()) and patch the file.
  vector<uint8_t> out_bytes(out_stream.tellp());
  out_stream.seekg(0);
  out_stream.read((char*)out_bytes.data(), out_bytes.size());
  uint32_t unpacked_size = asmjs::calculate_unpacked_size(out_bytes.data());
  asmjs::patch_unpacked_size(out_stream, unpacked_size);

  return 0;
}
catch(const ios::failure& err)
{
  cerr << "Failed with runtime error: " << err.what() << endl;
  return -1;
}
catch(const runtime_error& err)
{
  cerr << "Failed with runtime error: " << err.what() << endl;
  return -1;
}