/* File object implementation (what's left of it -- see io.py) */

#include "Python.h"

#include "pycore_call.h"          // _PyObject_CallNoArgs()

#include "pycore_runtime.h"       // _PyRuntime

#include "pycore_unicodeobject.h" // _PyUnicode_AsUTF8String()

#ifdef HAVE_UNISTD_H

#  include <unistd.h>             // isatty()

#endif

#if defined(HAVE_GETC_UNLOCKED) && !defined(_Py_MEMORY_SANITIZER)

   /* clang MemorySanitizer doesn't yet understand getc_unlocked. */

#  define GETC(f) getc_unlocked(f)

#  define FLOCKFILE(f) flockfile(f)

#  define FUNLOCKFILE(f) funlockfile(f)

#else

#  define GETC(f) getc(f)

#  define FLOCKFILE(f)

#  define FUNLOCKFILE(f)

#endif

/* Newline flags */

#define NEWLINE_UNKNOWN 0       /* No newline seen, yet */

#define NEWLINE_CR 1            /* \r newline seen */

#define NEWLINE_LF 2            /* \n newline seen */

#define NEWLINE_CRLF 4          /* \r\n newline seen */

/* External C interface */

PyObject *

PyFile_FromFd(int fd, const char *name, const char *mode, int buffering, const char *encoding,

              const char *errors, const char *newline, int closefd)

{

    PyObject *open, *stream;

    /* import _io in case we are being used to open io.py */

    open = PyImport_ImportModuleAttrString("_io", "open");

    if (open == NULL)

        return NULL;

    stream = PyObject_CallFunction(open, "isisssO", fd, mode,

                                  buffering, encoding, errors,

                                  newline, closefd ? Py_True : Py_False);

    Py_DECREF(open);

    if (stream == NULL)

        return NULL;

    /* ignore name attribute because the name attribute of _BufferedIOMixin

       and TextIOWrapper is read only */

    return stream;

}

PyObject *

PyFile_GetLine(PyObject *f, int n)

{

    PyObject *result;

    if (f == NULL) {

        PyErr_BadInternalCall();

        return NULL;

    }

    if (n <= 0) {

        result = PyObject_CallMethodNoArgs(f, &_Py_ID(readline));

    }

    else {

        result = _PyObject_CallMethod(f, &_Py_ID(readline), "i", n);

    }

    if (result != NULL && !PyBytes_Check(result) &&

        !PyUnicode_Check(result)) {

        PyErr_Format(PyExc_TypeError,

                     "%T.readline() must return a str, not %T", f, result);

        Py_SETREF(result, NULL);

    }

    if (n < 0 && result != NULL && PyBytes_Check(result)) {

        const char *s = PyBytes_AS_STRING(result);

        Py_ssize_t len = PyBytes_GET_SIZE(result);

        if (len == 0) {

            Py_SETREF(result, NULL);

            PyErr_SetString(PyExc_EOFError,

                            "EOF when reading a line");

        }

        else if (s[len-1] == '\n') {

            (void) _PyBytes_Resize(&result, len-1);

        }

    }

    if (n < 0 && result != NULL && PyUnicode_Check(result)) {

        Py_ssize_t len = PyUnicode_GET_LENGTH(result);

        if (len == 0) {

            Py_SETREF(result, NULL);

            PyErr_SetString(PyExc_EOFError,

                            "EOF when reading a line");

        }

        else if (PyUnicode_READ_CHAR(result, len-1) == '\n') {

            PyObject *v;

            v = PyUnicode_Substring(result, 0, len-1);

            Py_SETREF(result, v);

        }

    }

    return result;

}

/* Interfaces to write objects/strings to file-like objects */

int

PyFile_WriteObject(PyObject *v, PyObject *f, int flags)

{

    PyObject *writer, *value, *result;

    if (f == NULL) {

        PyErr_SetString(PyExc_TypeError, "writeobject with NULL file");

        return -1;

    }

    writer = PyObject_GetAttr(f, &_Py_ID(write));

    if (writer == NULL)

        return -1;

    if (flags & Py_PRINT_RAW) {

        value = PyObject_Str(v);

    }

    else

        value = PyObject_Repr(v);

    if (value == NULL) {

        Py_DECREF(writer);

        return -1;

    }

    result = PyObject_CallOneArg(writer, value);

    Py_DECREF(value);

    Py_DECREF(writer);

    if (result == NULL)

        return -1;

    Py_DECREF(result);

    return 0;

}

int

PyFile_WriteString(const char *s, PyObject *f)

{

    if (f == NULL) {

        /* Should be caused by a pre-existing error */

        if (!PyErr_Occurred())

            PyErr_SetString(PyExc_SystemError,

                            "null file for PyFile_WriteString");

        return -1;

    }

    else if (!PyErr_Occurred()) {

        PyObject *v = PyUnicode_FromString(s);

        int err;

        if (v == NULL)

            return -1;

        err = PyFile_WriteObject(v, f, Py_PRINT_RAW);

        Py_DECREF(v);

        return err;

    }

    else

        return -1;

}

/* Try to get a file-descriptor from a Python object.  If the object

   is an integer, its value is returned.  If not, the

   object's fileno() method is called if it exists; the method must return

   an integer, which is returned as the file descriptor value.

   -1 is returned on failure.

*/

int

PyObject_AsFileDescriptor(PyObject *o)

{

    int fd;

    PyObject *meth;

    if (PyLong_Check(o)) {

        if (PyBool_Check(o)) {

            if (PyErr_WarnEx(PyExc_RuntimeWarning,

                    "bool is used as a file descriptor", 1))

            {

                return -1;

            }

        }

        fd = PyLong_AsInt(o);

    }

    else if (PyObject_GetOptionalAttr(o, &_Py_ID(fileno), &meth) < 0) {

        return -1;

    }

    else if (meth != NULL) {

        PyObject *fno = _PyObject_CallNoArgs(meth);

        Py_DECREF(meth);

        if (fno == NULL)

            return -1;

        if (PyLong_Check(fno)) {

            fd = PyLong_AsInt(fno);

            Py_DECREF(fno);

        }

        else {

            PyErr_Format(PyExc_TypeError,

                         "%T.fileno() must return an int, not %T", o, fno);

            Py_DECREF(fno);

            return -1;

        }

    }

    else {

        PyErr_SetString(PyExc_TypeError,

                        "argument must be an int, or have a fileno() method.");

        return -1;

    }

    if (fd == -1 && PyErr_Occurred())

        return -1;

    if (fd < 0) {

        PyErr_Format(PyExc_ValueError,

                     "file descriptor cannot be a negative integer (%i)",

                     fd);

        return -1;

    }

    return fd;

}

int

_Py_Off_t_Converter(PyObject *arg, void *addr)

{

#ifdef HAVE_LARGEFILE_SUPPORT

    *((Py_off_t *)addr) = PyLong_AsLongLong(arg);

#else

    *((Py_off_t *)addr) = PyLong_AsLong(arg);

#endif

    return PyErr_Occurred() ? 0 : 1;

}

int

_PyLong_FileDescriptor_Converter(PyObject *o, void *ptr)

{

    int fd = PyObject_AsFileDescriptor(o);

    if (fd == -1) {

        return 0;

    }

    *(int *)ptr = fd;

    return 1;

}

char *

_Py_UniversalNewlineFgetsWithSize(char *buf, int n, FILE *stream, PyObject *fobj, size_t* size)

{

    char *p = buf;

    int c;

    if (fobj) {

        errno = ENXIO;          /* What can you do... */

        return NULL;

    }

    FLOCKFILE(stream);

    while (--n > 0 && (c = GETC(stream)) != EOF ) {

        if (c == '\r') {

            // A \r is translated into a \n, and we skip an adjacent \n, if any.

            c = GETC(stream);

            if (c != '\n') {

                ungetc(c, stream);

                c = '\n';

            }

        }

        *p++ = c;

        if (c == '\n') {

            break;

        }

    }

    FUNLOCKFILE(stream);

    *p = '\0';

    if (p == buf) {

        return NULL;

    }

    *size = p - buf;

    return buf;

}

/*

** Py_UniversalNewlineFgets is an fgets variation that understands

** all of \r, \n and \r\n conventions.

** The stream should be opened in binary mode.

** The fobj parameter exists solely for legacy reasons and must be NULL.

** Note that we need no error handling: fgets() treats error and eof

** identically.

*/

char *

Py_UniversalNewlineFgets(char *buf, int n, FILE *stream, PyObject *fobj) {

    size_t size;

    return _Py_UniversalNewlineFgetsWithSize(buf, n, stream, fobj, &size);

}

/* **************************** std printer ****************************

 * The stdprinter is used during the boot strapping phase as a preliminary

 * file like object for sys.stderr.

 */

typedef struct {

    PyObject_HEAD

    int fd;

} PyStdPrinter_Object;

/*[clinic input]

class stdprinter "PyStdPrinter_Object *" "&PyStdPrinter_Type"

[clinic start generated code]*/

/*[clinic end generated code: output=da39a3ee5e6b4b0d input=031bf557c18c5df5]*/

#include "clinic/fileobject.c.h"

PyObject *

PyFile_NewStdPrinter(int fd)

{

    PyStdPrinter_Object *self;

    if (fd != fileno(stdout) && fd != fileno(stderr)) {

        /* not enough infrastructure for PyErr_BadInternalCall() */

        return NULL;

    }

    self = PyObject_New(PyStdPrinter_Object,

                        &PyStdPrinter_Type);

    if (self != NULL) {

        self->fd = fd;

    }

    return (PyObject*)self;

}

/*[clinic input]

stdprinter.write

    text as unicode: unicode

    /

Write the text to the stream.

[clinic start generated code]*/

static PyObject *

stdprinter_write_impl(PyStdPrinter_Object *self, PyObject *unicode)

/*[clinic end generated code: output=069c9645803fe8ad input=65041d6d7a23aff4]*/

{

    PyObject *bytes = NULL;

    const char *str;

    Py_ssize_t n;

    int err;

    /* The function can clear the current exception */

    assert(!PyErr_Occurred());

    if (self->fd < 0) {

        /* fd might be invalid on Windows

         * I can't raise an exception here. It may lead to an

         * unlimited recursion in the case stderr is invalid.

         */

        Py_RETURN_NONE;

    }

    /* Encode Unicode to UTF-8/backslashreplace */

    str = PyUnicode_AsUTF8AndSize(unicode, &n);

    if (str == NULL) {

        PyErr_Clear();

        bytes = _PyUnicode_AsUTF8String(unicode, "backslashreplace");

        if (bytes == NULL)

            return NULL;

        str = PyBytes_AS_STRING(bytes);

        n = PyBytes_GET_SIZE(bytes);

    }

    n = _Py_write(self->fd, str, n);

    /* save errno, it can be modified indirectly by Py_XDECREF() */

    err = errno;

    Py_XDECREF(bytes);

    if (n == -1) {

        if (err == EAGAIN) {

            PyErr_Clear();

            Py_RETURN_NONE;

        }

        return NULL;

    }

    return PyLong_FromSsize_t(n);

}

static PyObject *

stdprinter_fileno(PyObject *op, PyObject *Py_UNUSED(ignored))

{

    PyStdPrinter_Object *self = (PyStdPrinter_Object*)op;

    return PyLong_FromLong((long) self->fd);

}

static PyObject *

stdprinter_repr(PyObject *op)

{

    PyStdPrinter_Object *self = (PyStdPrinter_Object*)op;

    return PyUnicode_FromFormat("<stdprinter(fd=%d) object at %p>",

                                self->fd, self);

}

static PyObject *

stdprinter_noop(PyObject *self, PyObject *Py_UNUSED(ignored))

{

    Py_RETURN_NONE;

}

static PyObject *

stdprinter_isatty(PyObject *op, PyObject *Py_UNUSED(ignored))

{

    PyStdPrinter_Object *self = (PyStdPrinter_Object*)op;

    long res;

    if (self->fd < 0) {

        Py_RETURN_FALSE;

    }

    Py_BEGIN_ALLOW_THREADS

    res = isatty(self->fd);

    Py_END_ALLOW_THREADS

    return PyBool_FromLong(res);

}

static PyMethodDef stdprinter_methods[] = {

    {"close", stdprinter_noop, METH_NOARGS, ""},

    {"flush", stdprinter_noop, METH_NOARGS, ""},

    {"fileno", stdprinter_fileno, METH_NOARGS, ""},

    {"isatty", stdprinter_isatty, METH_NOARGS, ""},

    STDPRINTER_WRITE_METHODDEF

    {NULL,              NULL}  /*sentinel */

};

static PyObject *

get_closed(PyObject *self, void *Py_UNUSED(closure))

{

    Py_RETURN_FALSE;

}

static PyObject *

get_mode(PyObject *self, void *Py_UNUSED(closure))

{

    return PyUnicode_FromString("w");

}

static PyObject *

get_encoding(PyObject *self, void *Py_UNUSED(closure))

{

    Py_RETURN_NONE;

}

static PyGetSetDef stdprinter_getsetlist[] = {

    {"closed", get_closed, NULL, "True if the file is closed"},

    {"encoding", get_encoding, NULL, "Encoding of the file"},

    {"mode", get_mode, NULL, "String giving the file mode"},

    {0},

};

PyTypeObject PyStdPrinter_Type = {

    PyVarObject_HEAD_INIT(&PyType_Type, 0)

    "stderrprinter",                            /* tp_name */

    sizeof(PyStdPrinter_Object),                /* tp_basicsize */

    0,                                          /* tp_itemsize */

    /* methods */

    0,                                          /* tp_dealloc */

    0,                                          /* tp_vectorcall_offset */

    0,                                          /* tp_getattr */

    0,                                          /* tp_setattr */

    0,                                          /* tp_as_async */

    stdprinter_repr,                            /* tp_repr */

    0,                                          /* tp_as_number */

    0,                                          /* tp_as_sequence */

    0,                                          /* tp_as_mapping */

    0,                                          /* tp_hash */

    0,                                          /* tp_call */

    0,                                          /* tp_str */

    PyObject_GenericGetAttr,                    /* tp_getattro */

    0,                                          /* tp_setattro */

    0,                                          /* tp_as_buffer */

    Py_TPFLAGS_DEFAULT | Py_TPFLAGS_DISALLOW_INSTANTIATION, /* tp_flags */

    0,                                          /* tp_doc */

    0,                                          /* tp_traverse */

    0,                                          /* tp_clear */

    0,                                          /* tp_richcompare */

    0,                                          /* tp_weaklistoffset */

    0,                                          /* tp_iter */

    0,                                          /* tp_iternext */

    stdprinter_methods,                         /* tp_methods */

    0,                                          /* tp_members */

    stdprinter_getsetlist,                      /* tp_getset */

    0,                                          /* tp_base */

    0,                                          /* tp_dict */

    0,                                          /* tp_descr_get */

    0,                                          /* tp_descr_set */

    0,                                          /* tp_dictoffset */

    0,                                          /* tp_init */

    PyType_GenericAlloc,                        /* tp_alloc */

    0,                                          /* tp_new */

    PyObject_Free,                              /* tp_free */

};

/* ************************** open_code hook ***************************

 * The open_code hook allows embedders to override the method used to

 * open files that are going to be used by the runtime to execute code

 */

int

PyFile_SetOpenCodeHook(Py_OpenCodeHookFunction hook, void *userData) {

    if (Py_IsInitialized() &&

        PySys_Audit("setopencodehook", NULL) < 0) {

        return -1;

    }

    if (_PyRuntime.open_code_hook) {

        if (Py_IsInitialized()) {

            PyErr_SetString(PyExc_SystemError,

                "failed to change existing open_code hook");

        }

        return -1;

    }

    _PyRuntime.open_code_hook = hook;

    _PyRuntime.open_code_userdata = userData;

    return 0;

}

PyObject *

PyFile_OpenCodeObject(PyObject *path)

{

    PyObject *f = NULL;

    if (!PyUnicode_Check(path)) {

        PyErr_Format(PyExc_TypeError, "'path' must be 'str', not '%.200s'",

                     Py_TYPE(path)->tp_name);

        return NULL;

    }

    Py_OpenCodeHookFunction hook = _PyRuntime.open_code_hook;

    if (hook) {

        f = hook(path, _PyRuntime.open_code_userdata);

    } else {

        PyObject *open = PyImport_ImportModuleAttrString("_io", "open");

        if (open) {

            f = PyObject_CallFunction(open, "Os", path, "rb");

            Py_DECREF(open);

        }

    }

    return f;

}

PyObject *

PyFile_OpenCode(const char *utf8path)

{

    PyObject *pathobj = PyUnicode_FromString(utf8path);

    PyObject *f;

    if (!pathobj) {

        return NULL;

    }

    f = PyFile_OpenCodeObject(pathobj);

    Py_DECREF(pathobj);

    return f;

}

int

_PyFile_Flush(PyObject *file)

{

    PyObject *tmp = PyObject_CallMethodNoArgs(file, &_Py_ID(flush));

    if (tmp == NULL) {

        return -1;

    }

    Py_DECREF(tmp);

    return 0;

}