/* Write Python objects to files and read them back.

This is primarily intended for writing and reading compiled Python code,

even though dicts and frozendicts, lists, sets and frozensets,

not commonly seen in code objects, are supported.

Version 3 of this protocol properly supports circular links

and sharing. */

#include "Python.h"

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

#include "pycore_code.h" // _PyCode_New()

#include "pycore_hashtable.h" // _Py_hashtable_t

#include "pycore_long.h" // _PyLong_IsZero()

#include "pycore_object.h" // _PyObject_IsUniquelyReferenced

#include "pycore_pystate.h" // _PyInterpreterState_GET()

#include "pycore_setobject.h" // _PySet_NextEntryRef()

#include "pycore_tuple.h" // _PyTuple_FromPairSteal

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

#include "marshal.h" // Py_MARSHAL_VERSION

#ifdef __APPLE__

# include "TargetConditionals.h"

#endif /* __APPLE__ */

/*[clinic input]

module marshal

[clinic start generated code]*/

/*[clinic end generated code: output=da39a3ee5e6b4b0d input=c982b7930dee17db]*/

#include "clinic/marshal.c.h"

/* High water mark to determine when the marshalled object is dangerously deep

* and risks coring the interpreter. When the object stack gets this deep,

* raise an exception instead of continuing.

* On Windows debug builds, reduce this value.

*

* BUG: https://bugs.python.org/issue33720

* On Windows PGO builds, the r_object function overallocates its stack and

* can cause a stack overflow. We reduce the maximum depth for all Windows

* releases to protect against this.

* #if defined(MS_WINDOWS) && defined(Py_DEBUG)

*/

#if defined(MS_WINDOWS)

# define MAX_MARSHAL_STACK_DEPTH 1000

#elif defined(__wasi__)

# define MAX_MARSHAL_STACK_DEPTH 1500

// TARGET_OS_IPHONE covers any non-macOS Apple platform.

// It won't be defined on older macOS SDKs

#elif defined(__APPLE__) && defined(TARGET_OS_IPHONE) && TARGET_OS_IPHONE

# define MAX_MARSHAL_STACK_DEPTH 1500

#else

# define MAX_MARSHAL_STACK_DEPTH 2000

#endif

/* Supported types */

#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_BINARY_FLOAT 'g' // Version 0 uses TYPE_FLOAT instead.

#define TYPE_BINARY_COMPLEX 'y' // Version 0 uses TYPE_COMPLEX instead.

#define TYPE_LONG 'l' // See also TYPE_INT.

#define TYPE_STRING 's' // Bytes. (Name comes from Python 2.)

#define TYPE_TUPLE '(' // See also TYPE_SMALL_TUPLE.

#define TYPE_LIST '['

#define TYPE_DICT '{'

#define TYPE_FROZENDICT '}'

#define TYPE_CODE 'c'

#define TYPE_UNICODE 'u'

#define TYPE_UNKNOWN '?'

// added in version 2:

#define TYPE_SET '<'

#define TYPE_FROZENSET '>'

// added in version 5:

#define TYPE_SLICE ':'

// Remember to update the version and documentation when adding new types.

/* Special cases for unicode strings (added in version 4) */

#define TYPE_INTERNED 't' // Version 1+

#define TYPE_ASCII 'a'

#define TYPE_ASCII_INTERNED 'A'

#define TYPE_SHORT_ASCII 'z'

#define TYPE_SHORT_ASCII_INTERNED 'Z'

/* Special cases for small objects */

#define TYPE_INT 'i' // All versions. 32-bit encoding.

#define TYPE_SMALL_TUPLE ')' // Version 4+

/* Supported for backwards compatibility */

#define TYPE_COMPLEX 'x' // Generated for version 0 only.

#define TYPE_FLOAT 'f' // Generated for version 0 only.

#define TYPE_INT64 'I' // Not generated any more.

/* References (added in version 3) */

#define TYPE_REF 'r'

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

// Error codes:

#define WFERR_OK 0

#define WFERR_UNMARSHALLABLE 1

#define WFERR_NESTEDTOODEEP 2

#define WFERR_NOMEMORY 3

#define WFERR_CODE_NOT_ALLOWED 4

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;

int allow_code;

} 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)

#else

# define W_SIZE w_long

#endif

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);

}

/* We assume that Python ints are stored internally in base some power of

2**15; for the sake of portability we'll always read and write them in base

exactly 2**15. */

#define PyLong_MARSHAL_SHIFT 15

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

#define PyLong_MARSHAL_MASK (PyLong_MARSHAL_BASE - 1)

#define W_TYPE(t, p) do { \

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

} while(0)

static PyObject *

_PyMarshal_WriteObjectToString(PyObject *x, int version, int allow_code);

#define _r_digits(bitsize) \

static void \

_r_digits##bitsize(const uint ## bitsize ## _t *digits, Py_ssize_t n, \

uint8_t negative, Py_ssize_t marshal_ratio, WFILE *p) \

{ \

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

Py_ssize_t l = (n - 1)*marshal_ratio; \

uint ## bitsize ## _t d = digits[n - 1]; \

\

assert(marshal_ratio > 0); \

assert(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)(negative ? -l : l), p); \

\

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

d = digits[i]; \

for (Py_ssize_t j = 0; j < marshal_ratio; j++) { \

w_short(d & PyLong_MARSHAL_MASK, p); \

d >>= PyLong_MARSHAL_SHIFT; \

} \

assert(d == 0); \

} \

d = digits[n - 1]; \

do { \

w_short(d & PyLong_MARSHAL_MASK, p); \

d >>= PyLong_MARSHAL_SHIFT; \

} while (d != 0); \

}

_r_digits(16)

_r_digits(32)

#undef _r_digits

static void

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

{

W_TYPE(TYPE_LONG, p);

if (_PyLong_IsZero(ob)) {

w_long((long)0, p);

return;

}

PyLongExport long_export;

if (PyLong_Export((PyObject *)ob, &long_export) < 0) {

p->depth--;

p->error = WFERR_UNMARSHALLABLE;

return;

}

if (!long_export.digits) {

int8_t sign = long_export.value < 0 ? -1 : 1;

uint64_t abs_value = _Py_ABS_CAST(uint64_t, long_export.value);

uint64_t d = abs_value;

long l = 0;

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

do {

d >>= PyLong_MARSHAL_SHIFT;

l += sign;

} while (d);

w_long(l, p);

d = abs_value;

do {

w_short(d & PyLong_MARSHAL_MASK, p);

d >>= PyLong_MARSHAL_SHIFT;

} while (d);

return;

}

const PyLongLayout *layout = PyLong_GetNativeLayout();

Py_ssize_t marshal_ratio = layout->bits_per_digit/PyLong_MARSHAL_SHIFT;

/* must be a multiple of PyLong_MARSHAL_SHIFT */

assert(layout->bits_per_digit % PyLong_MARSHAL_SHIFT == 0);

assert(layout->bits_per_digit >= PyLong_MARSHAL_SHIFT);

/* other assumptions on PyLongObject internals */

assert(layout->bits_per_digit <= 32);

assert(layout->digits_order == -1);

assert(layout->digit_endianness == (PY_LITTLE_ENDIAN ? -1 : 1));

assert(layout->digit_size == 2 || layout->digit_size == 4);

if (layout->digit_size == 4) {

_r_digits32(long_export.digits, long_export.ndigits,

long_export.negative, marshal_ratio, p);

}

else {

_r_digits16(long_export.digits, long_export.ndigits,

long_export.negative, marshal_ratio, p);

}

PyLong_FreeExport(&long_export);

}

static void

w_float_bin(double v, WFILE *p)

{

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;

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

return 0; /* not writing object references */

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

* But we use TYPE_REF always for interned string, to PYC file stable

* as possible.

*/

if (_PyObject_IsUniquelyReferenced(v) &&

!(PyUnicode_CheckExact(v) && PyUnicode_CHECK_INTERNED(v))) {

return 0;

}

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

if (entry != NULL) {

/* write the reference index to the stream */

uintptr_t w = (uintptr_t)entry->value;

if (w & 0x80000000LU) {

PyErr_Format(PyExc_ValueError, "cannot marshal recursion %T objects", v);

goto err;

}

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

assert(w <= 0x7fffffff);

w_byte(TYPE_REF, p);

w_long((int)w, p);

return 1;

} else {

size_t w = p->hashtable->nentries;

/* we don't support long indices */

if (w >= 0x7fffffff) {

PyErr_SetString(PyExc_ValueError, "too many objects");

goto err;

}

// Corresponding code should call w_complete() after

// writing the object.

if (PyCode_Check(v) || PySlice_Check(v) || PyFrozenDict_CheckExact(v)) {

w |= 0x80000000LU;

}

if (_Py_hashtable_set(p->hashtable, Py_NewRef(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_complete(PyObject *v, WFILE *p)

{

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

return;

}

if (_PyObject_IsUniquelyReferenced(v)) {

return;

}

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

if (entry == NULL) {

return;

}

assert(entry != NULL);

uintptr_t w = (uintptr_t)entry->value;

assert(w & 0x80000000LU);

w &= ~0x80000000LU;

entry->value = (void *)(uintptr_t)w;

}

static void

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

static void

w_object(PyObject *v, WFILE *p)

{

char flag = '\0';

if (p->error != WFERR_OK) {

return;

}

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

#endif

{

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 (PyAnyDict_CheckExact(v)) {

Py_ssize_t pos;

PyObject *key, *value;

if (PyFrozenDict_CheckExact(v)) {

if (p->version < 6) {

w_byte(TYPE_UNKNOWN, p);

p->error = WFERR_UNMARSHALLABLE;

return;

}

W_TYPE(TYPE_FROZENDICT, p);

}

else {

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);

if (PyFrozenDict_CheckExact(v)) {

w_complete(v, 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);

// bpo-37596: To support reproducible builds, sets and frozensets need

// to have their elements serialized in a consistent order (even when

// they have been scrambled by hash randomization). To ensure this, we

// use an order equivalent to sorted(v, key=marshal.dumps):

PyObject *pairs = PyList_New(n);

if (pairs == NULL) {

p->error = WFERR_NOMEMORY;

return;

}

Py_ssize_t i = 0;

Py_BEGIN_CRITICAL_SECTION(v);

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

PyObject *dump = _PyMarshal_WriteObjectToString(value,

p->version, p->allow_code);

if (dump == NULL) {

p->error = WFERR_UNMARSHALLABLE;

Py_DECREF(value);

break;

}

PyObject *pair = _PyTuple_FromPairSteal(dump, value);

if (pair == NULL) {

p->error = WFERR_NOMEMORY;

break;

}

PyList_SET_ITEM(pairs, i++, pair);

}

Py_END_CRITICAL_SECTION();

if (p->error == WFERR_UNMARSHALLABLE || p->error == WFERR_NOMEMORY) {

Py_DECREF(pairs);

return;

}

assert(i == n);

if (PyList_Sort(pairs)) {

p->error = WFERR_NOMEMORY;

Py_DECREF(pairs);

return;

}

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

PyObject *pair = PyList_GET_ITEM(pairs, i);

value = PyTuple_GET_ITEM(pair, 1);

w_object(value, p);

}

Py_DECREF(pairs);

}

else if (PyCode_Check(v)) {

if (!p->allow_code) {

p->error = WFERR_CODE_NOT_ALLOWED;

return;

}

PyCodeObject *co = (PyCodeObject *)v;

PyObject *co_code = _PyCode_GetCode(co);

if (co_code == NULL) {

p->error = WFERR_NOMEMORY;

return;

}

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_stacksize, p);

w_long(co->co_flags, p);

w_object(co_code, p);

w_object(co->co_consts, p);

w_object(co->co_names, p);

w_object(co->co_localsplusnames, p);

w_object(co->co_localspluskinds, p);

w_object(co->co_filename, p);

w_object(co->co_name, p);

w_object(co->co_qualname, p);

w_long(co->co_firstlineno, p);

w_object(co->co_linetable, p);

w_object(co->co_exceptiontable, p);

Py_DECREF(co_code);

w_complete(v, 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 if (PySlice_Check(v)) {

if (p->version < 5) {

w_byte(TYPE_UNKNOWN, p);

p->error = WFERR_UNMARSHALLABLE;

return;

}

PySliceObject *slice = (PySliceObject *)v;

W_TYPE(TYPE_SLICE, p);

w_object(slice->start, p);

w_object(slice->stop, p);

w_object(slice->step, p);

w_complete(v, p);

}

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);

}

}

/* version currently has no effect for writing ints. */

/* Note that while the documentation states that this function

* can error, currently it never does. Setting an exception in

* this function should be regarded as an API-breaking change.

*/

void

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);

}

void

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;

wf.allow_code = 1;

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 */

int allow_code;

} 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 {

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_CallMethod(p->readable, &_Py_ID(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)

{

if (p->ptr != NULL) {

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

return (unsigned char) *p->ptr++;

}

}

else if (!p->readable) {

assert(p->fp);

int c = getc(p->fp);

if (c != EOF) {

return c;

}

}

else {

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

if (ptr != NULL) {

return *(const unsigned char *) ptr;

}

return EOF;

}

PyErr_SetString(PyExc_EOFError,

"EOF read where not expected");

return EOF;

}

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);

#endif

}

return x;

}

/* r_long64 deals with the TYPE_INT64 code. */

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 */);

}

#define _w_digits(bitsize) \

static int \

_w_digits##bitsize(uint ## bitsize ## _t *digits, Py_ssize_t size, \

Py_ssize_t marshal_ratio, \

int shorts_in_top_digit, RFILE *p) \

{ \

uint ## bitsize ## _t d; \

\

assert(size >= 1); \

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

d = 0; \

for (Py_ssize_t j = 0; j < marshal_ratio; j++) { \

int md = r_short(p); \

if (md < 0 || md > PyLong_MARSHAL_BASE) { \

goto bad_digit; \

} \

d += (uint ## bitsize ## _t)md << j*PyLong_MARSHAL_SHIFT; \