pyodide/src/main.c

#include <Python.h>
#include <emscripten.h>

#include "hiwire.h"
#include "js2python.h"
#include "jsimport.h"
#include "jsproxy.h"
#include "pyimport.h"
#include "pyproxy.h"
#include "python2js.h"
#include "runpython.h"

/*
  TODO: This is a workaround for a weird emscripten compiler bug. The
  matplotlib/_qhull.so extension makes function pointer calls with these
  signatures, but since nothing with that signature exists in the MAIN_MODULE,
  it can't link the SIDE_MODULE. Creating these dummy functions here seems to
  work around the problem.
*/

void
__foo(double x)
{}

void
__foo2(double x, double y)
{}

void
__foo3(double x, double y, double z)
{}

void
__foo4(int a, double b, int c, int d, int e)
{}

/* END WORKAROUND */

int
main(int argc, char** argv)
{
  hiwire_setup();

  setenv("PYTHONHOME", "/", 0);

  Py_InitializeEx(0);

  // This doesn't seem to work anymore, but I'm keeping it for good measure anyway
  // The effective way to turn this off is below: setting sys.done_write_bytecode = True
  setenv("PYTHONDONTWRITEBYTECODE", "1", 0);

  PyObject* sys = PyImport_ImportModule("sys");
  if (sys == NULL) {
    return 1;
  }
  if (PyObject_SetAttrString(sys, "dont_write_bytecode", Py_True)) {
    return 1;
  }

  // By disabling the cache_tag, Python won't look for cached bytecode files when
  // importing modules, which saves on filesystem I/O time
  PyObject *implementation = PyObject_GetAttrString(sys, "implementation");
  if (implementation == NULL) {
    return 1;
  }

  if (PyObject_SetAttrString(implementation, "cache_tag", Py_None)) {
    return 1;
  }

  Py_DECREF(implementation);
  Py_DECREF(sys);

  if (js2python_init() || JsImport_init() || JsProxy_init() ||
      pyimport_init() || pyproxy_init() || python2js_init() ||
      runpython_init_js() || runpython_init_py() || runpython_finalize_js()) {
    return 1;
  }

  printf("Python initialization complete\n");

  emscripten_exit_with_live_runtime();
  return 0;
}