fnode.cc

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <libgen.h>
#include <vector>
#include <string>

using namespace std;

int main(int argc, char **argv)
{
  string exe_path;

  // Not relative or absolute path
  if (NULL == strchr(argv[0], '/'))
  {
    // search PATH
    size_t pos_a = 0, pos_b = 0;
    string path(getenv("PATH"));
    vector<string> paths;
    while (pos_b < path.size())
    {
      pos_b = path.find(":", pos_a);
      if (string::npos == pos_b)
      {
        pos_b = path.size();
      }

      if (pos_b > pos_a)
      {
        string check = path.substr(pos_a, pos_b - pos_a) + "/" + argv[0];
        if (0 == access(check.c_str(), X_OK))
        {
          exe_path = check;
          break;
        }
      }

      pos_a = pos_b + 1;
    }
  }
  else
  {
    char *mp = realpath(argv[0], NULL);
    if (mp)
    {
      exe_path = mp;
    }
  }

  if (exe_path.empty())
  {
    fprintf(stderr, "Unable to determine realpath of %s\n", argv[0]);
    exit(-1);
  }

  char *my_dir = dirname((char *)exe_path.c_str());
  string node_path(my_dir);
  size_t dir_len = node_path.find_last_of("/");
  string top_dir(
      node_path, 0,
      string::npos == dir_len
          ? node_path.size()
          : dir_len);
  free(my_dir);

  node_path += "/_node";

  char *args[argc + 3];
  int copy_off = 0;

  string flat_module = top_dir + "/lib/node_modules/flat-module";
  if (0 == access(flat_module.c_str(), F_OK))
  {
    printf("node_path %s flat_module %s\n", node_path.c_str(), flat_module.c_str());
    copy_off = 2;
    args[1] = (char *)"-r";
    args[2] = (char *)flat_module.c_str();
  }

  printf("argc %d\n", argc);
  for (int i = 1; i < argc; i++)
  {
    args[i + copy_off] = argv[i];
  }

  args[0] = (char *)exe_path.c_str();
  args[argc + copy_off] = NULL;
  execv(node_path.c_str(), args);

  fprintf(stderr, "Executing %s failed\n", node_path.c_str());

  return -1;
}