#!/usr/bin/env python
"""
Create a C file for embedding one or more Cython source files.
Requires Cython 0.11.2 (or perhaps newer).

See Demos/freeze/README.rst for more details.
"""
from __future__ import print_function

import optparse
from os.path import splitext, basename

usage= '%prog [-o outfile] [-p] module [module ...]'
description = 'Create a C file for embedding Cython modules.'
p = optparse.OptionParser(usage=usage, description=description)
p.add_option('-o', '--output', metavar='FILE',
        help='write output to FILE instead of standard output')
p.add_option('-p', '--pymain', action='store_true', default=False,
        help='do not automatically run the first module as __main__')

options, args = p.parse_args()

if len(args) < 1:
    p.print_help()
    p.exit(1)

if options.output:
    import sys
    old_stdout = sys.stdout
    sys.stdout = open(options.output, 'w')

modules = [basename(splitext(x)[0]).replace('.', '_') for x in args]

print("""\
#include <Python.h>
#include <locale.h>
#include <stdio.h>
#include <stdlib.h>

#ifdef __FreeBSD__
#include <floatingpoint.h>
#endif

#if PY_MAJOR_VERSION < 3
# define MODINIT(name)  init ## name
#else
# define MODINIT(name)  PyInit_ ## name
#endif
""")

for name in modules:
    print("PyMODINIT_FUNC MODINIT(%s) (void);" % name)

print("""
static struct _inittab inittab[] = {""")

for name in modules:
    print('    {"%(name)s", MODINIT(%(name)s)},' % {'name' : name})

print("""    {NULL, NULL}
};
""", end=' ')

if not options.pymain:
    print("\nextern int __pyx_module_is_main_%s;" % modules[0])

print("""
#if PY_MAJOR_VERSION < 3
int main(int argc, char** argv) {
#elif defined(WIN32) || defined(MS_WINDOWS)
int wmain(int argc, wchar_t **argv) {
#else
static int python_main(int argc, wchar_t **argv) {
#endif
""", end=' ')
if not options.pymain:
    print("""\
    PyObject *m = NULL;
    int r = 0;
""", end=' ')
print("""\
    /* 754 requires that FP exceptions run in "no stop" mode by default,
     * and until C vendors implement C99's ways to control FP exceptions,
     * Python requires non-stop mode.  Alas, some platforms enable FP
     * exceptions by default.  Here we disable them.
     */
#ifdef __FreeBSD__
    fp_except_t m;

    m = fpgetmask();
    fpsetmask(m & ~FP_X_OFL);
#endif
    if (PyImport_ExtendInittab(inittab)) {
        fprintf(stderr, "No memory\\n");
        exit(1);
    }
""", end=' ')
if options.pymain:
    print("""\
    return Py_Main(argc, argv);
}
""")
else:
    print("""\
    Py_SetProgramName(argv[0]);
    Py_Initialize();
    PySys_SetArgv(argc, argv);
    __pyx_module_is_main_%(main)s = 1;
    m = PyImport_ImportModule(inittab[0].name);
    if (!m) {
        r = 1;
        PyErr_Print(); /* This exits with the right code if SystemExit. */
#if PY_MAJOR_VERSION < 3
        if (Py_FlushLine())
            PyErr_Clear();
#endif
    }
    Py_XDECREF(m);
    Py_Finalize();
    return r;
}
""" % {'main' : modules[0]}, end=' ')

print(r"""
#if PY_MAJOR_VERSION >= 3 && !defined(WIN32) && !defined(MS_WINDOWS)
static wchar_t*
char2wchar(char* arg)
{
        wchar_t *res;
#ifdef HAVE_BROKEN_MBSTOWCS
        /* Some platforms have a broken implementation of
         * mbstowcs which does not count the characters that
         * would result from conversion.  Use an upper bound.
         */
        size_t argsize = strlen(arg);
#else
        size_t argsize = mbstowcs(NULL, arg, 0);
#endif
        size_t count;
        unsigned char *in;
        wchar_t *out;
#ifdef HAVE_MBRTOWC
        mbstate_t mbs;
#endif
        if (argsize != (size_t)-1) {
                res = (wchar_t *)malloc((argsize+1)*sizeof(wchar_t));
                if (!res)
                        goto oom;
                count = mbstowcs(res, arg, argsize+1);
                if (count != (size_t)-1) {
                        wchar_t *tmp;
                        /* Only use the result if it contains no
                           surrogate characters. */
                        for (tmp = res; *tmp != 0 &&
                                     (*tmp < 0xd800 || *tmp > 0xdfff); tmp++)
                                ;
                        if (*tmp == 0)
                                return res;
                }
                free(res);
        }
        /* Conversion failed. Fall back to escaping with surrogateescape. */
#ifdef HAVE_MBRTOWC
        /* Try conversion with mbrtwoc (C99), and escape non-decodable bytes. */

        /* Overallocate; as multi-byte characters are in the argument, the
           actual output could use less memory. */
        argsize = strlen(arg) + 1;
        res = malloc(argsize*sizeof(wchar_t));
        if (!res) goto oom;
        in = (unsigned char*)arg;
        out = res;
        memset(&mbs, 0, sizeof mbs);
        while (argsize) {
                size_t converted = mbrtowc(out, (char*)in, argsize, &mbs);
                if (converted == 0)
                        /* Reached end of string; null char stored. */
                        break;
                if (converted == (size_t)-2) {
                        /* Incomplete character. This should never happen,
                           since we provide everything that we have -
                           unless there is a bug in the C library, or I
                           misunderstood how mbrtowc works. */
                        fprintf(stderr, "unexpected mbrtowc result -2\n");
                        return NULL;
                }
                if (converted == (size_t)-1) {
                        /* Conversion error. Escape as UTF-8b, and start over
                           in the initial shift state. */
                        *out++ = 0xdc00 + *in++;
                        argsize--;
                        memset(&mbs, 0, sizeof mbs);
                        continue;
                }
                if (*out >= 0xd800 && *out <= 0xdfff) {
                        /* Surrogate character.  Escape the original
                           byte sequence with surrogateescape. */
                        argsize -= converted;
                        while (converted--)
                                *out++ = 0xdc00 + *in++;
                        continue;
                }
                /* successfully converted some bytes */
                in += converted;
                argsize -= converted;
                out++;
        }
#else
        /* Cannot use C locale for escaping; manually escape as if charset
           is ASCII (i.e. escape all bytes > 128. This will still roundtrip
           correctly in the locale's charset, which must be an ASCII superset. */
        res = malloc((strlen(arg)+1)*sizeof(wchar_t));
        if (!res) goto oom;
        in = (unsigned char*)arg;
        out = res;
        while(*in)
                if(*in < 128)
                        *out++ = *in++;
                else
                        *out++ = 0xdc00 + *in++;
        *out = 0;
#endif
        return res;
oom:
        fprintf(stderr, "out of memory\n");
        return NULL;
}

int
main(int argc, char **argv)
{
        wchar_t **argv_copy = (wchar_t **)malloc(sizeof(wchar_t*)*argc);
        /* We need a second copies, as Python might modify the first one. */
        wchar_t **argv_copy2 = (wchar_t **)malloc(sizeof(wchar_t*)*argc);
        int i, res;
        char *oldloc;
        if (!argv_copy || !argv_copy2) {
                fprintf(stderr, "out of memory\n");
                return 1;
        }
        oldloc = strdup(setlocale(LC_ALL, NULL));
        setlocale(LC_ALL, "");
        for (i = 0; i < argc; i++) {
                argv_copy2[i] = argv_copy[i] = char2wchar(argv[i]);
                if (!argv_copy[i])
                        return 1;
        }
        setlocale(LC_ALL, oldloc);
        free(oldloc);
        res = python_main(argc, argv_copy);
        for (i = 0; i < argc; i++) {
                free(argv_copy2[i]);
        }
        free(argv_copy);
        free(argv_copy2);
        return res;
}
#endif""")
