#define PY_SSIZE_T_CLEAN

#include "Python.h"

#include "longintrepr.h"

#include "code.h"

#include "marshal.h"

#include "pycore_hashtable.h"

#include "clinic/marshal.c.h"

#if defined(MS_WINDOWS)

#define MAX_MARSHAL_STACK_DEPTH 1000

#define MAX_MARSHAL_STACK_DEPTH 2000

#define TYPE_NULL '0'

#define TYPE_NONE 'N'

#define TYPE_FALSE 'F'

#define TYPE_TRUE 'T'

#define TYPE_STOPITER 'S'

#define TYPE_ELLIPSIS '.'

#define TYPE_INT 'i'

#define TYPE_INT64 'I'

#define TYPE_FLOAT 'f'

#define TYPE_BINARY_FLOAT 'g'

#define TYPE_COMPLEX 'x'

#define TYPE_BINARY_COMPLEX 'y'

#define TYPE_LONG 'l'

#define TYPE_STRING 's'

#define TYPE_INTERNED 't'

#define TYPE_REF 'r'

#define TYPE_TUPLE '('

#define TYPE_LIST '['

#define TYPE_DICT '{'

#define TYPE_CODE 'c'

#define TYPE_UNICODE 'u'

#define TYPE_UNKNOWN '?'

#define TYPE_SET '<'

#define TYPE_FROZENSET '>'

#define FLAG_REF '\x80' /* with a type, add obj to index */

#define TYPE_ASCII 'a'

#define TYPE_ASCII_INTERNED 'A'

#define TYPE_SMALL_TUPLE ')'

#define TYPE_SHORT_ASCII 'z'

#define TYPE_SHORT_ASCII_INTERNED 'Z'

#define WFERR_OK 0

#define WFERR_UNMARSHALLABLE 1

#define WFERR_NESTEDTOODEEP 2

#define WFERR_NOMEMORY 3

typedef struct {

FILE *fp;

int error; /* see WFERR_* values */

int depth;

PyObject *str;

char *ptr;

const char *end;

char *buf;

_Py_hashtable_t *hashtable;

int version;

} WFILE;

#define w_byte(c, p) do { \

if ((p)->ptr != (p)->end || w_reserve((p), 1)) \

*(p)->ptr++ = (c); \

} while(0)

static void

w_flush(WFILE *p)

{

assert(p->fp != NULL);

fwrite(p->buf, 1, p->ptr - p->buf, p->fp);

p->ptr = p->buf;

}

static int

w_reserve(WFILE *p, Py_ssize_t needed)

{

Py_ssize_t pos, size, delta;

if (p->ptr == NULL)

return 0; /* An error already occurred */

if (p->fp != NULL) {

w_flush(p);

return needed <= p->end - p->ptr;

}

assert(p->str != NULL);

pos = p->ptr - p->buf;

size = PyBytes_GET_SIZE(p->str);

if (size > 16*1024*1024)

delta = (size >> 3); /* 12.5% overallocation */

else

delta = size + 1024;

delta = Py_MAX(delta, needed);

if (delta > PY_SSIZE_T_MAX - size) {

p->error = WFERR_NOMEMORY;

return 0;

}

size += delta;

if (_PyBytes_Resize(&p->str, size) != 0) {

p->end = p->ptr = p->buf = NULL;

return 0;

}

else {

p->buf = PyBytes_AS_STRING(p->str);

p->ptr = p->buf + pos;

p->end = p->buf + size;

return 1;

}

}

static void

w_string(const void *s, Py_ssize_t n, WFILE *p)

{

Py_ssize_t m;

if (!n || p->ptr == NULL)

return;

m = p->end - p->ptr;

if (p->fp != NULL) {

if (n <= m) {

memcpy(p->ptr, s, n);

p->ptr += n;

}

else {

w_flush(p);

fwrite(s, 1, n, p->fp);

}

}

else {

if (n <= m || w_reserve(p, n - m)) {

memcpy(p->ptr, s, n);

p->ptr += n;

}

}

}

static void

w_short(int x, WFILE *p)

{

w_byte((char)( x & 0xff), p);

w_byte((char)((x>> 8) & 0xff), p);

}

static void

w_long(long x, WFILE *p)

{

w_byte((char)( x & 0xff), p);

w_byte((char)((x>> 8) & 0xff), p);

w_byte((char)((x>>16) & 0xff), p);

w_byte((char)((x>>24) & 0xff), p);

}

#define SIZE32_MAX 0x7FFFFFFF

#if SIZEOF_SIZE_T > 4

# define W_SIZE(n, p) do { \

if ((n) > SIZE32_MAX) { \

(p)->depth--; \

(p)->error = WFERR_UNMARSHALLABLE; \

return; \

} \

w_long((long)(n), p); \

} while(0)

# define W_SIZE w_long

static void

w_pstring(const void *s, Py_ssize_t n, WFILE *p)

{

W_SIZE(n, p);

w_string(s, n, p);

}

static void

w_short_pstring(const void *s, Py_ssize_t n, WFILE *p)

{

w_byte(Py_SAFE_DOWNCAST(n, Py_ssize_t, unsigned char), p);

w_string(s, n, p);

}

#define PyLong_MARSHAL_SHIFT 15

#define PyLong_MARSHAL_BASE ((short)1 << PyLong_MARSHAL_SHIFT)

#define PyLong_MARSHAL_MASK (PyLong_MARSHAL_BASE - 1)

#if PyLong_SHIFT % PyLong_MARSHAL_SHIFT != 0

#error "PyLong_SHIFT must be a multiple of PyLong_MARSHAL_SHIFT"

#define PyLong_MARSHAL_RATIO (PyLong_SHIFT / PyLong_MARSHAL_SHIFT)

#define W_TYPE(t, p) do { \

w_byte((t) | flag, (p)); \

} while(0)

static void

w_PyLong(const PyLongObject *ob, char flag, WFILE *p)

{

Py_ssize_t i, j, n, l;

digit d;

W_TYPE(TYPE_LONG, p);

if (Py_SIZE(ob) == 0) {

w_long((long)0, p);

return;

}

/* set l to number of base PyLong_MARSHAL_BASE digits */

n = Py_ABS(Py_SIZE(ob));

l = (n-1) * PyLong_MARSHAL_RATIO;

d = ob->ob_digit[n-1];

assert(d != 0); /* a PyLong is always normalized */

do {

d >>= PyLong_MARSHAL_SHIFT;

l++;

} while (d != 0);

if (l > SIZE32_MAX) {

p->depth--;

p->error = WFERR_UNMARSHALLABLE;

return;

}

w_long((long)(Py_SIZE(ob) > 0 ? l : -l), p);

for (i=0; i < n-1; i++) {

d = ob->ob_digit[i];

for (j=0; j < PyLong_MARSHAL_RATIO; j++) {

w_short(d & PyLong_MARSHAL_MASK, p);

d >>= PyLong_MARSHAL_SHIFT;

}

assert (d == 0);

}

d = ob->ob_digit[n-1];

do {

w_short(d & PyLong_MARSHAL_MASK, p);

d >>= PyLong_MARSHAL_SHIFT;

} while (d != 0);

}

static void

w_float_bin(double v, WFILE *p)

{

unsigned char buf[8];

if (_PyFloat_Pack8(v, buf, 1) < 0) {

p->error = WFERR_UNMARSHALLABLE;

return;

}

w_string(buf, 8, p);

}

static void

w_float_str(double v, WFILE *p)

{

char *buf = PyOS_double_to_string(v, 'g', 17, 0, NULL);

if (!buf) {

p->error = WFERR_NOMEMORY;

return;

}

w_short_pstring(buf, strlen(buf), p);

PyMem_Free(buf);

}

static int

w_ref(PyObject *v, char *flag, WFILE *p)

{

_Py_hashtable_entry_t *entry;

int w;

if (p->version < 3 || p->hashtable == NULL)

return 0; /* not writing object references */

/* if it has only one reference, it definitely isn't shared */

if (Py_REFCNT(v) == 1)

return 0;

entry = _Py_hashtable_get_entry(p->hashtable, v);

if (entry != NULL) {

/* write the reference index to the stream */

w = (int)(uintptr_t)entry->value;

/* we don't store "long" indices in the dict */

assert(0 <= w && w <= 0x7fffffff);

w_byte(TYPE_REF, p);

w_long(w, p);

return 1;

} else {

size_t s = p->hashtable->nentries;

/* we don't support long indices */

if (s >= 0x7fffffff) {

PyErr_SetString(PyExc_ValueError, "too many objects");

goto err;

}

w = (int)s;

Py_INCREF(v);

if (_Py_hashtable_set(p->hashtable, v, (void *)(uintptr_t)w) < 0) {

Py_DECREF(v);

goto err;

}

*flag |= FLAG_REF;

return 0;

}

err:

p->error = WFERR_UNMARSHALLABLE;

return 1;

}

static void

w_complex_object(PyObject *v, char flag, WFILE *p);

static void

w_object(PyObject *v, WFILE *p)

{

char flag = '\0';

p->depth++;

if (p->depth > MAX_MARSHAL_STACK_DEPTH) {

p->error = WFERR_NESTEDTOODEEP;

}

else if (v == NULL) {

w_byte(TYPE_NULL, p);

}

else if (v == Py_None) {

w_byte(TYPE_NONE, p);

}

else if (v == PyExc_StopIteration) {

w_byte(TYPE_STOPITER, p);

}

else if (v == Py_Ellipsis) {

w_byte(TYPE_ELLIPSIS, p);

}

else if (v == Py_False) {

w_byte(TYPE_FALSE, p);

}

else if (v == Py_True) {

w_byte(TYPE_TRUE, p);

}

else if (!w_ref(v, &flag, p))

w_complex_object(v, flag, p);

p->depth--;

}

static void

w_complex_object(PyObject *v, char flag, WFILE *p)

{

Py_ssize_t i, n;

if (PyLong_CheckExact(v)) {

int overflow;

long x = PyLong_AsLongAndOverflow(v, &overflow);

if (overflow) {

w_PyLong((PyLongObject *)v, flag, p);

}

else {

#if SIZEOF_LONG > 4

long y = Py_ARITHMETIC_RIGHT_SHIFT(long, x, 31);

if (y && y != -1) {

/* Too large for TYPE_INT */

w_PyLong((PyLongObject*)v, flag, p);

}

else

{

W_TYPE(TYPE_INT, p);

w_long(x, p);

}

}

}

else if (PyFloat_CheckExact(v)) {

if (p->version > 1) {

W_TYPE(TYPE_BINARY_FLOAT, p);

w_float_bin(PyFloat_AS_DOUBLE(v), p);

}

else {

W_TYPE(TYPE_FLOAT, p);

w_float_str(PyFloat_AS_DOUBLE(v), p);

}

}

else if (PyComplex_CheckExact(v)) {

if (p->version > 1) {

W_TYPE(TYPE_BINARY_COMPLEX, p);

w_float_bin(PyComplex_RealAsDouble(v), p);

w_float_bin(PyComplex_ImagAsDouble(v), p);

}

else {

W_TYPE(TYPE_COMPLEX, p);

w_float_str(PyComplex_RealAsDouble(v), p);

w_float_str(PyComplex_ImagAsDouble(v), p);

}

}

else if (PyBytes_CheckExact(v)) {

W_TYPE(TYPE_STRING, p);

w_pstring(PyBytes_AS_STRING(v), PyBytes_GET_SIZE(v), p);

}

else if (PyUnicode_CheckExact(v)) {

if (p->version >= 4 && PyUnicode_IS_ASCII(v)) {

int is_short = PyUnicode_GET_LENGTH(v) < 256;

if (is_short) {

if (PyUnicode_CHECK_INTERNED(v))

W_TYPE(TYPE_SHORT_ASCII_INTERNED, p);

else

W_TYPE(TYPE_SHORT_ASCII, p);

w_short_pstring(PyUnicode_1BYTE_DATA(v),

PyUnicode_GET_LENGTH(v), p);

}

else {

if (PyUnicode_CHECK_INTERNED(v))

W_TYPE(TYPE_ASCII_INTERNED, p);

else

W_TYPE(TYPE_ASCII, p);

w_pstring(PyUnicode_1BYTE_DATA(v),

PyUnicode_GET_LENGTH(v), p);

}

}

else {

PyObject *utf8;

utf8 = PyUnicode_AsEncodedString(v, "utf8", "surrogatepass");

if (utf8 == NULL) {

p->depth--;

p->error = WFERR_UNMARSHALLABLE;

return;

}

if (p->version >= 3 && PyUnicode_CHECK_INTERNED(v))

W_TYPE(TYPE_INTERNED, p);

else

W_TYPE(TYPE_UNICODE, p);

w_pstring(PyBytes_AS_STRING(utf8), PyBytes_GET_SIZE(utf8), p);

Py_DECREF(utf8);

}

}

else if (PyTuple_CheckExact(v)) {

n = PyTuple_GET_SIZE(v);

if (p->version >= 4 && n < 256) {

W_TYPE(TYPE_SMALL_TUPLE, p);

w_byte((unsigned char)n, p);

}

else {

W_TYPE(TYPE_TUPLE, p);

W_SIZE(n, p);

}

for (i = 0; i < n; i++) {

w_object(PyTuple_GET_ITEM(v, i), p);

}

}

else if (PyList_CheckExact(v)) {

W_TYPE(TYPE_LIST, p);

n = PyList_GET_SIZE(v);

W_SIZE(n, p);

for (i = 0; i < n; i++) {

w_object(PyList_GET_ITEM(v, i), p);

}

}

else if (PyDict_CheckExact(v)) {

Py_ssize_t pos;

PyObject *key, *value;

W_TYPE(TYPE_DICT, p);

/* This one is NULL object terminated! */

pos = 0;

while (PyDict_Next(v, &pos, &key, &value)) {

w_object(key, p);

w_object(value, p);

}

w_object((PyObject *)NULL, p);

}

else if (PyAnySet_CheckExact(v)) {

PyObject *value;

Py_ssize_t pos = 0;

Py_hash_t hash;

if (PyFrozenSet_CheckExact(v))

W_TYPE(TYPE_FROZENSET, p);

else

W_TYPE(TYPE_SET, p);

n = PySet_GET_SIZE(v);

W_SIZE(n, p);

while (_PySet_NextEntry(v, &pos, &value, &hash)) {

w_object(value, p);

}

}

else if (PyCode_Check(v)) {

PyCodeObject *co = (PyCodeObject *)v;

W_TYPE(TYPE_CODE, p);

w_long(co->co_argcount, p);

w_long(co->co_posonlyargcount, p);

w_long(co->co_kwonlyargcount, p);

w_long(co->co_nlocals, p);

w_long(co->co_stacksize, p);

w_long(co->co_flags, p);

w_object(co->co_code, p);

w_object(co->co_consts, p);

w_object(co->co_names, p);

w_object(co->co_varnames, p);

w_object(co->co_freevars, p);

w_object(co->co_cellvars, p);

w_object(co->co_filename, p);

w_object(co->co_name, p);

w_long(co->co_firstlineno, p);

w_object(co->co_lnotab, p);

}

else if (PyObject_CheckBuffer(v)) {

/* Write unknown bytes-like objects as a bytes object */

Py_buffer view;

if (PyObject_GetBuffer(v, &view, PyBUF_SIMPLE) != 0) {

w_byte(TYPE_UNKNOWN, p);

p->depth--;

p->error = WFERR_UNMARSHALLABLE;

return;

}

W_TYPE(TYPE_STRING, p);

w_pstring(view.buf, view.len, p);

PyBuffer_Release(&view);

}

else {

W_TYPE(TYPE_UNKNOWN, p);

p->error = WFERR_UNMARSHALLABLE;

}

}

static void

w_decref_entry(void *key)

{

PyObject *entry_key = (PyObject *)key;

Py_XDECREF(entry_key);

}

static int

w_init_refs(WFILE *wf, int version)

{

if (version >= 3) {

wf->hashtable = _Py_hashtable_new_full(_Py_hashtable_hash_ptr,

_Py_hashtable_compare_direct,

w_decref_entry, NULL, NULL);

if (wf->hashtable == NULL) {

PyErr_NoMemory();

return -1;

}

}

return 0;

}

static void

w_clear_refs(WFILE *wf)

{

if (wf->hashtable != NULL) {

_Py_hashtable_destroy(wf->hashtable);

}

}

PyMarshal_WriteLongToFile(long x, FILE *fp, int version)

{

char buf[4];

WFILE wf;

memset(&wf, 0, sizeof(wf));

wf.fp = fp;

wf.ptr = wf.buf = buf;

wf.end = wf.ptr + sizeof(buf);

wf.error = WFERR_OK;

wf.version = version;

w_long(x, &wf);

w_flush(&wf);

}

PyMarshal_WriteObjectToFile(PyObject *x, FILE *fp, int version)

{

char buf[BUFSIZ];

WFILE wf;

if (PySys_Audit("marshal.dumps", "Oi", x, version) < 0) {

return; /* caller must check PyErr_Occurred() */

}

memset(&wf, 0, sizeof(wf));

wf.fp = fp;

wf.ptr = wf.buf = buf;

wf.end = wf.ptr + sizeof(buf);

wf.error = WFERR_OK;

wf.version = version;

if (w_init_refs(&wf, version)) {

return; /* caller must check PyErr_Occurred() */

}

w_object(x, &wf);

w_clear_refs(&wf);

w_flush(&wf);

}

typedef struct {

FILE *fp;

int depth;

PyObject *readable; /* Stream-like object being read from */

const char *ptr;

const char *end;

char *buf;

Py_ssize_t buf_size;

PyObject *refs; /* a list */

} RFILE;

static const char *

r_string(Py_ssize_t n, RFILE *p)

{

Py_ssize_t read = -1;

if (p->ptr != NULL) {

/* Fast path for loads() */

const char *res = p->ptr;

Py_ssize_t left = p->end - p->ptr;

if (left < n) {

PyErr_SetString(PyExc_EOFError,

"marshal data too short");

return NULL;

}

p->ptr += n;

return res;

}

if (p->buf == NULL) {

p->buf = PyMem_MALLOC(n);

if (p->buf == NULL) {

PyErr_NoMemory();

return NULL;

}

p->buf_size = n;

}

else if (p->buf_size < n) {

char *tmp = PyMem_REALLOC(p->buf, n);

if (tmp == NULL) {

PyErr_NoMemory();

return NULL;

}

p->buf = tmp;

p->buf_size = n;

}

if (!p->readable) {

assert(p->fp != NULL);

read = fread(p->buf, 1, n, p->fp);

}

else {

_Py_IDENTIFIER(readinto);

PyObject *res, *mview;

Py_buffer buf;

if (PyBuffer_FillInfo(&buf, NULL, p->buf, n, 0, PyBUF_CONTIG) == -1)

return NULL;

mview = PyMemoryView_FromBuffer(&buf);

if (mview == NULL)

return NULL;

res = _PyObject_CallMethodId(p->readable, &PyId_readinto, "N", mview);

if (res != NULL) {

read = PyNumber_AsSsize_t(res, PyExc_ValueError);

Py_DECREF(res);

}

}

if (read != n) {

if (!PyErr_Occurred()) {

if (read > n)

PyErr_Format(PyExc_ValueError,

"read() returned too much data: "

"%zd bytes requested, %zd returned",

n, read);

else

PyErr_SetString(PyExc_EOFError,

"EOF read where not expected");

}

return NULL;

}

return p->buf;

}

static int

r_byte(RFILE *p)

{

int c = EOF;

if (p->ptr != NULL) {

if (p->ptr < p->end)

c = (unsigned char) *p->ptr++;

return c;

}

if (!p->readable) {

assert(p->fp);

c = getc(p->fp);

}

else {

const char *ptr = r_string(1, p);

if (ptr != NULL)

c = *(const unsigned char *) ptr;

}

return c;

}

static int

r_short(RFILE *p)

{

short x = -1;

const unsigned char *buffer;

buffer = (const unsigned char *) r_string(2, p);

if (buffer != NULL) {

x = buffer[0];

x |= buffer[1] << 8;

/* Sign-extension, in case short greater than 16 bits */

x |= -(x & 0x8000);

}

return x;

}

static long

r_long(RFILE *p)

{

long x = -1;

const unsigned char *buffer;

buffer = (const unsigned char *) r_string(4, p);

if (buffer != NULL) {

x = buffer[0];

x |= (long)buffer[1] << 8;

x |= (long)buffer[2] << 16;

x |= (long)buffer[3] << 24;

#if SIZEOF_LONG > 4

/* Sign extension for 64-bit machines */

x |= -(x & 0x80000000L);

}

return x;

}

static PyObject *

r_long64(RFILE *p)

{

const unsigned char *buffer = (const unsigned char *) r_string(8, p);

if (buffer == NULL) {

return NULL;

}

return _PyLong_FromByteArray(buffer, 8,

1 /* little endian */,

1 /* signed */);

}

static PyObject *

r_PyLong(RFILE *p)

{

PyLongObject *ob;

long n, size, i;

int j, md, shorts_in_top_digit;

digit d;

n = r_long(p);

if (PyErr_Occurred())

return NULL;

if (n == 0)

return (PyObject *)_PyLong_New(0);

if (n < -SIZE32_MAX || n > SIZE32_MAX) {

PyErr_SetString(PyExc_ValueError,

"bad marshal data (long size out of range)");

return NULL;

}

size = 1 + (Py_ABS(n) - 1) / PyLong_MARSHAL_RATIO;

shorts_in_top_digit = 1 + (Py_ABS(n) - 1) % PyLong_MARSHAL_RATIO;

ob = _PyLong_New(size);

if (ob == NULL)

return NULL;

Py_SET_SIZE(ob, n > 0 ? size : -size);

for (i = 0; i < size-1; i++) {

d = 0;

for (j=0; j < PyLong_MARSHAL_RATIO; j++) {

md = r_short(p);

if (PyErr_Occurred()) {

Py_DECREF(ob);

return NULL;

}

if (md < 0 || md > PyLong_MARSHAL_BASE)

goto bad_digit;

d += (digit)md << j*PyLong_MARSHAL_SHIFT;

}

ob->ob_digit[i] = d;

}

d = 0;

for (j=0; j < shorts_in_top_digit; j++) {

md = r_short(p);

if (PyErr_Occurred()) {

Py_DECREF(ob);

return NULL;

}

if (md < 0 || md > PyLong_MARSHAL_BASE)

goto bad_digit;

/* topmost marshal digit should be nonzero */

if (md == 0 && j == shorts_in_top_digit - 1) {

Py_DECREF(ob);

PyErr_SetString(PyExc_ValueError,

"bad marshal data (unnormalized long data)");

return NULL;

}

d += (digit)md << j*PyLong_MARSHAL_SHIFT;

}

if (PyErr_Occurred()) {

Py_DECREF(ob);

return NULL;

}

/* top digit should be nonzero, else the resulting PyLong won't be

ob->ob_digit[size-1] = d;

return (PyObject *)ob;

bad_digit:

Py_DECREF(ob);

PyErr_SetString(PyExc_ValueError,

"bad marshal data (digit out of range in long)");

return NULL;

}

static double

r_float_bin(RFILE *p)

{

const unsigned char *buf = (const unsigned char *) r_string(8, p);

if (buf == NULL)

return -1;

return _PyFloat_Unpack8(buf, 1);

}

_Py_NO_INLINE static double

r_float_str(RFILE *p)

{

int n;

char buf[256];

const char *ptr;

n = r_byte(p);

if (n == EOF) {

PyErr_SetString(PyExc_EOFError,

"EOF read where object expected");

return -1;

}

ptr = r_string(n, p);

if (ptr == NULL) {

return -1;

}

memcpy(buf, ptr, n);

buf[n] = '\0';

return PyOS_string_to_double(buf, NULL, NULL);

}

static Py_ssize_t

r_ref_reserve(int flag, RFILE *p)

{

if (flag) { /* currently only FLAG_REF is defined */

Py_ssize_t idx = PyList_GET_SIZE(p->refs);

if (idx >= 0x7ffffffe) {

PyErr_SetString(PyExc_ValueError, "bad marshal data (index list too large)");

return -1;

}

if (PyList_Append(p->refs, Py_None) < 0)

return -1;

return idx;

} else

return 0;

}

static PyObject *

r_ref_insert(PyObject *o, Py_ssize_t idx, int flag, RFILE *p)

{

if (o != NULL && flag) { /* currently only FLAG_REF is defined */

PyObject *tmp = PyList_GET_ITEM(p->refs, idx);

Py_INCREF(o);

PyList_SET_ITEM(p->refs, idx, o);

Py_DECREF(tmp);

}

return o;

}

static PyObject *

r_ref(PyObject *o, int flag, RFILE *p)

{

assert(flag & FLAG_REF);

if (o == NULL)

return NULL;

if (PyList_Append(p->refs, o) < 0) {

Py_DECREF(o); /* release the new object */

return NULL;

}

return o;

}

static PyObject *

r_object(RFILE *p)

{

/* NULL is a valid return value, it does not necessarily means that

PyObject *v, *v2;

Py_ssize_t idx = 0;

long i, n;

int type, code = r_byte(p);

int flag, is_interned = 0;

PyObject *retval = NULL;

if (code == EOF) {

PyErr_SetString(PyExc_EOFError,

"EOF read where object expected");

return NULL;

}

p->depth++;

if (p->depth > MAX_MARSHAL_STACK_DEPTH) {

p->depth--;

PyErr_SetString(PyExc_ValueError, "recursion limit exceeded");

return NULL;

}

flag = code & FLAG_REF;

type = code & ~FLAG_REF;

#define R_REF(O) do{\

if (flag) \

O = r_ref(O, flag, p);\

} while (0)

switch (type) {

case TYPE_NULL:

break;

case TYPE_NONE:

Py_INCREF(Py_None);

retval = Py_None;

break;

case TYPE_STOPITER:

Py_INCREF(PyExc_StopIteration);

retval = PyExc_StopIteration;

break;

case TYPE_ELLIPSIS:

Py_INCREF(Py_Ellipsis);

retval = Py_Ellipsis;

break;

case TYPE_FALSE:

Py_INCREF(Py_False);

retval = Py_False;

break;

case TYPE_TRUE:

Py_INCREF(Py_True);

retval = Py_True;

break;

case TYPE_INT:

n = r_long(p);