Mirror
/
cpython
mirror of https://github.com/python/cpython
4
1
Fork 0
Code Issues Releases Wiki Activity

gh-95382: Use cache for indentations in the JSON encoder (GH-118636)

This commit is contained in:
Serhiy Storchaka 2024-11-12 19:19:15 +02:00 committed by GitHub
parent 91f4908798
commit 6b2a19681e
No known key found for this signature in database
GPG Key ID: B5690EEEBB952194
1 changed files with 118 additions and 64 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

182
Modules/_json.c
View File

@ -86,11 +86,11 @@ encoder_dealloc(PyObject *self);
static int
encoder_clear(PyEncoderObject *self);
static int
encoder_listencode_list(PyEncoderObject *s, PyUnicodeWriter *writer, PyObject *seq, PyObject *newline_indent);
encoder_listencode_list(PyEncoderObject *s, PyUnicodeWriter *writer, PyObject *seq, Py_ssize_t indent_level, PyObject *indent_cache);
static int
encoder_listencode_obj(PyEncoderObject *s, PyUnicodeWriter *writer, PyObject *obj, PyObject *newline_indent);
encoder_listencode_obj(PyEncoderObject *s, PyUnicodeWriter *writer, PyObject *obj, Py_ssize_t indent_level, PyObject *indent_cache);
static int
encoder_listencode_dict(PyEncoderObject *s, PyUnicodeWriter *writer, PyObject *dct, PyObject *newline_indent);
encoder_listencode_dict(PyEncoderObject *s, PyUnicodeWriter *writer, PyObject *dct, Py_ssize_t indent_level, PyObject *indent_cache);
static PyObject *
_encoded_const(PyObject *obj);
static void
@ -1252,17 +1252,92 @@ encoder_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
return (PyObject *)s;
}
/* indent_cache is a list that contains intermixed values at even and odd
* positions:
*
* 2*k : '\n' + indent * (k + initial_indent_level)
* strings written after opening and before closing brackets
* 2*k-1 : item_separator + '\n' + indent * (k + initial_indent_level)
* strings written between items
*
* Its size is always an odd number.
*/
static PyObject *
_create_newline_indent(PyObject *indent, Py_ssize_t indent_level)
create_indent_cache(PyEncoderObject *s, Py_ssize_t indent_level)
{
PyObject *newline_indent = PyUnicode_FromOrdinal('\n');
if (newline_indent != NULL && indent_level) {
PyUnicode_AppendAndDel(&newline_indent,
PySequence_Repeat(indent, indent_level));
PySequence_Repeat(s->indent, indent_level));
}
return newline_indent;
if (newline_indent == NULL) {
return NULL;
}
PyObject *indent_cache = PyList_New(1);
if (indent_cache == NULL) {
Py_DECREF(newline_indent);
return NULL;
}
PyList_SET_ITEM(indent_cache, 0, newline_indent);
return indent_cache;
}
/* Extend indent_cache by adding values for the next level.
* It should have values for the indent_level-1 level before the call.
*/
static int
update_indent_cache(PyEncoderObject *s,
Py_ssize_t indent_level, PyObject *indent_cache)
{
assert(indent_level * 2 == PyList_GET_SIZE(indent_cache) + 1);
assert(indent_level > 0);
PyObject *newline_indent = PyList_GET_ITEM(indent_cache, (indent_level - 1)*2);
newline_indent = PyUnicode_Concat(newline_indent, s->indent);
if (newline_indent == NULL) {
return -1;
}
PyObject *separator_indent = PyUnicode_Concat(s->item_separator, newline_indent);
if (separator_indent == NULL) {
Py_DECREF(newline_indent);
return -1;
}
if (PyList_Append(indent_cache, separator_indent) < 0 ||
PyList_Append(indent_cache, newline_indent) < 0)
{
Py_DECREF(separator_indent);
Py_DECREF(newline_indent);
return -1;
}
Py_DECREF(separator_indent);
Py_DECREF(newline_indent);
return 0;
}
static PyObject *
get_item_separator(PyEncoderObject *s,
Py_ssize_t indent_level, PyObject *indent_cache)
{
assert(indent_level > 0);
if (indent_level * 2 > PyList_GET_SIZE(indent_cache)) {
if (update_indent_cache(s, indent_level, indent_cache) < 0) {
return NULL;
}
}
assert(indent_level * 2 < PyList_GET_SIZE(indent_cache));
return PyList_GET_ITEM(indent_cache, indent_level * 2 - 1);
}
static int
write_newline_indent(PyUnicodeWriter *writer,
Py_ssize_t indent_level, PyObject *indent_cache)
{
PyObject *newline_indent = PyList_GET_ITEM(indent_cache, indent_level * 2);
return PyUnicodeWriter_WriteStr(writer, newline_indent);
}
static PyObject *
encoder_call(PyEncoderObject *self, PyObject *args, PyObject *kwds)
{
@ -1280,20 +1355,20 @@ encoder_call(PyEncoderObject *self, PyObject *args, PyObject *kwds)
return NULL;
}
PyObject *newline_indent = NULL;
PyObject *indent_cache = NULL;
if (self->indent != Py_None) {
newline_indent = _create_newline_indent(self->indent, indent_level);
if (newline_indent == NULL) {
indent_cache = create_indent_cache(self, indent_level);
if (indent_cache == NULL) {
PyUnicodeWriter_Discard(writer);
return NULL;
}
}
if (encoder_listencode_obj(self, writer, obj, newline_indent)) {
if (encoder_listencode_obj(self, writer, obj, indent_level, indent_cache)) {
PyUnicodeWriter_Discard(writer);
Py_XDECREF(newline_indent);
Py_XDECREF(indent_cache);
return NULL;
}
Py_XDECREF(newline_indent);
Py_XDECREF(indent_cache);
PyObject *str = PyUnicodeWriter_Finish(writer);
if (str == NULL) {
@ -1381,7 +1456,8 @@ _steal_accumulate(PyUnicodeWriter *writer, PyObject *stolen)
static int
encoder_listencode_obj(PyEncoderObject *s, PyUnicodeWriter *writer,
PyObject *obj, PyObject *newline_indent)
PyObject *obj,
Py_ssize_t indent_level, PyObject *indent_cache)
{
/* Encode Python object obj to a JSON term */
PyObject *newobj;
@ -1421,14 +1497,14 @@ encoder_listencode_obj(PyEncoderObject *s, PyUnicodeWriter *writer,
else if (PyList_Check(obj) || PyTuple_Check(obj)) {
if (_Py_EnterRecursiveCall(" while encoding a JSON object"))
return -1;
rv = encoder_listencode_list(s, writer, obj, newline_indent);
rv = encoder_listencode_list(s, writer, obj, indent_level, indent_cache);
_Py_LeaveRecursiveCall();
return rv;
}
else if (PyDict_Check(obj)) {
if (_Py_EnterRecursiveCall(" while encoding a JSON object"))
return -1;
rv = encoder_listencode_dict(s, writer, obj, newline_indent);
rv = encoder_listencode_dict(s, writer, obj, indent_level, indent_cache);
_Py_LeaveRecursiveCall();
return rv;
}
@ -1462,7 +1538,7 @@ encoder_listencode_obj(PyEncoderObject *s, PyUnicodeWriter *writer,
Py_XDECREF(ident);
return -1;
}
rv = encoder_listencode_obj(s, writer, newobj, newline_indent);
rv = encoder_listencode_obj(s, writer, newobj, indent_level, indent_cache);
_Py_LeaveRecursiveCall();
Py_DECREF(newobj);
@ -1485,7 +1561,7 @@ encoder_listencode_obj(PyEncoderObject *s, PyUnicodeWriter *writer,
static int
encoder_encode_key_value(PyEncoderObject *s, PyUnicodeWriter *writer, bool *first,
PyObject *dct, PyObject *key, PyObject *value,
PyObject *newline_indent,
Py_ssize_t indent_level, PyObject *indent_cache,
PyObject *item_separator)
{
PyObject *keystr = NULL;
@ -1541,7 +1617,7 @@ encoder_encode_key_value(PyEncoderObject *s, PyUnicodeWriter *writer, bool *firs
if (PyUnicodeWriter_WriteStr(writer, s->key_separator) < 0) {
return -1;
}
if (encoder_listencode_obj(s, writer, value, newline_indent) < 0) {
if (encoder_listencode_obj(s, writer, value, indent_level, indent_cache) < 0) {
_PyErr_FormatNote("when serializing %T item %R", dct, key);
return -1;
}
@ -1550,15 +1626,14 @@ encoder_encode_key_value(PyEncoderObject *s, PyUnicodeWriter *writer, bool *firs
static int
encoder_listencode_dict(PyEncoderObject *s, PyUnicodeWriter *writer,
PyObject *dct, PyObject *newline_indent)
PyObject *dct,
Py_ssize_t indent_level, PyObject *indent_cache)
{
/* Encode Python dict dct a JSON term */
PyObject *ident = NULL;
PyObject *items = NULL;
PyObject *key, *value;
bool first = true;
PyObject *new_newline_indent = NULL;
PyObject *separator_indent = NULL;
if (PyDict_GET_SIZE(dct) == 0) {
/* Fast path */
@ -1585,19 +1660,13 @@ encoder_listencode_dict(PyEncoderObject *s, PyUnicodeWriter *writer,
goto bail;
}
PyObject *current_item_separator = s->item_separator; // borrowed reference
PyObject *separator = s->item_separator; // borrowed reference
if (s->indent != Py_None) {
new_newline_indent = PyUnicode_Concat(newline_indent, s->indent);
if (new_newline_indent == NULL) {
goto bail;
}
separator_indent = PyUnicode_Concat(current_item_separator, new_newline_indent);
if (separator_indent == NULL) {
goto bail;
}
// update item separator with a borrowed reference
current_item_separator = separator_indent;
if (PyUnicodeWriter_WriteStr(writer, new_newline_indent) < 0) {
indent_level++;
separator = get_item_separator(s, indent_level, indent_cache);
if (separator == NULL ||
write_newline_indent(writer, indent_level, indent_cache) < 0)
{
goto bail;
}
}
@ -1618,8 +1687,8 @@ encoder_listencode_dict(PyEncoderObject *s, PyUnicodeWriter *writer,
key = PyTuple_GET_ITEM(item, 0);
value = PyTuple_GET_ITEM(item, 1);
if (encoder_encode_key_value(s, writer, &first, dct, key, value,
new_newline_indent,
current_item_separator) < 0)
indent_level, indent_cache,
separator) < 0)
goto bail;
}
Py_CLEAR(items);
@ -1628,8 +1697,8 @@ encoder_listencode_dict(PyEncoderObject *s, PyUnicodeWriter *writer,
Py_ssize_t pos = 0;
while (PyDict_Next(dct, &pos, &key, &value)) {
if (encoder_encode_key_value(s, writer, &first, dct, key, value,
new_newline_indent,
current_item_separator) < 0)
indent_level, indent_cache,
separator) < 0)
goto bail;
}
}
@ -1640,10 +1709,8 @@ encoder_listencode_dict(PyEncoderObject *s, PyUnicodeWriter *writer,
Py_CLEAR(ident);
}
if (s->indent != Py_None) {
Py_CLEAR(new_newline_indent);
Py_CLEAR(separator_indent);
if (PyUnicodeWriter_WriteStr(writer, newline_indent) < 0) {
indent_level--;
if (write_newline_indent(writer, indent_level, indent_cache) < 0) {
goto bail;
}
}
@ -1656,20 +1723,17 @@ encoder_listencode_dict(PyEncoderObject *s, PyUnicodeWriter *writer,
bail:
Py_XDECREF(items);
Py_XDECREF(ident);
Py_XDECREF(separator_indent);
Py_XDECREF(new_newline_indent);
return -1;
}
static int
encoder_listencode_list(PyEncoderObject *s, PyUnicodeWriter *writer,
PyObject *seq, PyObject *newline_indent)
PyObject *seq,
Py_ssize_t indent_level, PyObject *indent_cache)
{
PyObject *ident = NULL;
PyObject *s_fast = NULL;
Py_ssize_t i;
PyObject *new_newline_indent = NULL;
PyObject *separator_indent = NULL;
ident = NULL;
s_fast = PySequence_Fast(seq, "_iterencode_list needs a sequence");
@ -1702,20 +1766,13 @@ encoder_listencode_list(PyEncoderObject *s, PyUnicodeWriter *writer,
PyObject *separator = s->item_separator; // borrowed reference
if (s->indent != Py_None) {
new_newline_indent = PyUnicode_Concat(newline_indent, s->indent);
if (new_newline_indent == NULL) {
indent_level++;
separator = get_item_separator(s, indent_level, indent_cache);
if (separator == NULL ||
write_newline_indent(writer, indent_level, indent_cache) < 0)
{
goto bail;
}
if (PyUnicodeWriter_WriteStr(writer, new_newline_indent) < 0) {
goto bail;
}
separator_indent = PyUnicode_Concat(separator, new_newline_indent);
if (separator_indent == NULL) {
goto bail;
}
separator = separator_indent; // assign separator with borrowed reference
}
for (i = 0; i < PySequence_Fast_GET_SIZE(s_fast); i++) {
PyObject *obj = PySequence_Fast_GET_ITEM(s_fast, i);
@ -1723,7 +1780,7 @@ encoder_listencode_list(PyEncoderObject *s, PyUnicodeWriter *writer,
if (PyUnicodeWriter_WriteStr(writer, separator) < 0)
goto bail;
}
if (encoder_listencode_obj(s, writer, obj, new_newline_indent)) {
if (encoder_listencode_obj(s, writer, obj, indent_level, indent_cache)) {
_PyErr_FormatNote("when serializing %T item %zd", seq, i);
goto bail;
}
@ -1735,9 +1792,8 @@ encoder_listencode_list(PyEncoderObject *s, PyUnicodeWriter *writer,
}
if (s->indent != Py_None) {
Py_CLEAR(new_newline_indent);
Py_CLEAR(separator_indent);
if (PyUnicodeWriter_WriteStr(writer, newline_indent) < 0) {
indent_level--;
if (write_newline_indent(writer, indent_level, indent_cache) < 0) {
goto bail;
}
}
@ -1751,8 +1807,6 @@ encoder_listencode_list(PyEncoderObject *s, PyUnicodeWriter *writer,
bail:
Py_XDECREF(ident);
Py_DECREF(s_fast);
Py_XDECREF(separator_indent);
Py_XDECREF(new_newline_indent);
return -1;
}