Issue #25353: Optimize unicode escape and raw unicode escape encoders to use

the new _PyBytesWriter API.
This commit is contained in:
Victor Stinner 2015-10-12 22:36:57 +02:00
parent d65e4f4eea
commit 358af13526
2 changed files with 93 additions and 64 deletions

View File

@ -2110,38 +2110,35 @@ save_bytes(PicklerObject *self, PyObject *obj)
static PyObject *
raw_unicode_escape(PyObject *obj)
{
PyObject *repr;
char *p;
Py_ssize_t i, size;
size_t expandsize;
void *data;
unsigned int kind;
_PyBytesWriter writer;
if (PyUnicode_READY(obj))
return NULL;
_PyBytesWriter_Init(&writer);
size = PyUnicode_GET_LENGTH(obj);
data = PyUnicode_DATA(obj);
kind = PyUnicode_KIND(obj);
if (kind == PyUnicode_4BYTE_KIND)
expandsize = 10;
else
expandsize = 6;
if ((size_t)size > (size_t)PY_SSIZE_T_MAX / expandsize)
return PyErr_NoMemory();
repr = PyBytes_FromStringAndSize(NULL, expandsize * size);
if (repr == NULL)
return NULL;
if (size == 0)
return repr;
assert(Py_REFCNT(repr) == 1);
p = _PyBytesWriter_Alloc(&writer, size);
if (p == NULL)
goto error;
writer.overallocate = 1;
p = PyBytes_AS_STRING(repr);
for (i=0; i < size; i++) {
Py_UCS4 ch = PyUnicode_READ(kind, data, i);
/* Map 32-bit characters to '\Uxxxxxxxx' */
if (ch >= 0x10000) {
/* -1: substract 1 preallocated byte */
p = _PyBytesWriter_Prepare(&writer, p, 10-1);
if (p == NULL)
goto error;
*p++ = '\\';
*p++ = 'U';
*p++ = Py_hexdigits[(ch >> 28) & 0xf];
@ -2153,8 +2150,13 @@ raw_unicode_escape(PyObject *obj)
*p++ = Py_hexdigits[(ch >> 4) & 0xf];
*p++ = Py_hexdigits[ch & 15];
}
/* Map 16-bit characters to '\uxxxx' */
/* Map 16-bit characters, '\\' and '\n' to '\uxxxx' */
else if (ch >= 256 || ch == '\\' || ch == '\n') {
/* -1: substract 1 preallocated byte */
p = _PyBytesWriter_Prepare(&writer, p, 6-1);
if (p == NULL)
goto error;
*p++ = '\\';
*p++ = 'u';
*p++ = Py_hexdigits[(ch >> 12) & 0xf];
@ -2166,10 +2168,12 @@ raw_unicode_escape(PyObject *obj)
else
*p++ = (char) ch;
}
size = p - PyBytes_AS_STRING(repr);
if (_PyBytes_Resize(&repr, size) < 0)
return NULL;
return repr;
return _PyBytesWriter_Finish(&writer, p);
error:
_PyBytesWriter_Dealloc(&writer);
return NULL;
}
static int

View File

@ -6052,11 +6052,10 @@ PyObject *
PyUnicode_AsUnicodeEscapeString(PyObject *unicode)
{
Py_ssize_t i, len;
PyObject *repr;
char *p;
int kind;
void *data;
Py_ssize_t expandsize = 0;
_PyBytesWriter writer;
/* Initial allocation is based on the longest-possible character
escape.
@ -6072,35 +6071,28 @@ PyUnicode_AsUnicodeEscapeString(PyObject *unicode)
}
if (PyUnicode_READY(unicode) == -1)
return NULL;
_PyBytesWriter_Init(&writer);
len = PyUnicode_GET_LENGTH(unicode);
kind = PyUnicode_KIND(unicode);
data = PyUnicode_DATA(unicode);
switch (kind) {
case PyUnicode_1BYTE_KIND: expandsize = 4; break;
case PyUnicode_2BYTE_KIND: expandsize = 6; break;
case PyUnicode_4BYTE_KIND: expandsize = 10; break;
}
if (len == 0)
return PyBytes_FromStringAndSize(NULL, 0);
if (len > (PY_SSIZE_T_MAX - 2 - 1) / expandsize)
return PyErr_NoMemory();
repr = PyBytes_FromStringAndSize(NULL,
2
+ expandsize*len
+ 1);
if (repr == NULL)
return NULL;
p = PyBytes_AS_STRING(repr);
p = _PyBytesWriter_Alloc(&writer, len);
if (p == NULL)
goto error;
writer.overallocate = 1;
for (i = 0; i < len; i++) {
Py_UCS4 ch = PyUnicode_READ(kind, data, i);
/* Escape backslashes */
if (ch == '\\') {
/* -1: substract 1 preallocated byte */
p = _PyBytesWriter_Prepare(&writer, p, 2-1);
if (p == NULL)
goto error;
*p++ = '\\';
*p++ = (char) ch;
continue;
@ -6109,6 +6101,11 @@ PyUnicode_AsUnicodeEscapeString(PyObject *unicode)
/* Map 21-bit characters to '\U00xxxxxx' */
else if (ch >= 0x10000) {
assert(ch <= MAX_UNICODE);
p = _PyBytesWriter_Prepare(&writer, p, 10-1);
if (p == NULL)
goto error;
*p++ = '\\';
*p++ = 'U';
*p++ = Py_hexdigits[(ch >> 28) & 0x0000000F];
@ -6124,6 +6121,10 @@ PyUnicode_AsUnicodeEscapeString(PyObject *unicode)
/* Map 16-bit characters to '\uxxxx' */
if (ch >= 256) {
p = _PyBytesWriter_Prepare(&writer, p, 6-1);
if (p == NULL)
goto error;
*p++ = '\\';
*p++ = 'u';
*p++ = Py_hexdigits[(ch >> 12) & 0x000F];
@ -6134,20 +6135,37 @@ PyUnicode_AsUnicodeEscapeString(PyObject *unicode)
/* Map special whitespace to '\t', \n', '\r' */
else if (ch == '\t') {
p = _PyBytesWriter_Prepare(&writer, p, 2-1);
if (p == NULL)
goto error;
*p++ = '\\';
*p++ = 't';
}
else if (ch == '\n') {
p = _PyBytesWriter_Prepare(&writer, p, 2-1);
if (p == NULL)
goto error;
*p++ = '\\';
*p++ = 'n';
}
else if (ch == '\r') {
p = _PyBytesWriter_Prepare(&writer, p, 2-1);
if (p == NULL)
goto error;
*p++ = '\\';
*p++ = 'r';
}
/* Map non-printable US ASCII to '\xhh' */
else if (ch < ' ' || ch >= 0x7F) {
/* -1: substract 1 preallocated byte */
p = _PyBytesWriter_Prepare(&writer, p, 4-1);
if (p == NULL)
goto error;
*p++ = '\\';
*p++ = 'x';
*p++ = Py_hexdigits[(ch >> 4) & 0x000F];
@ -6159,10 +6177,11 @@ PyUnicode_AsUnicodeEscapeString(PyObject *unicode)
*p++ = (char) ch;
}
assert(p - PyBytes_AS_STRING(repr) > 0);
if (_PyBytes_Resize(&repr, p - PyBytes_AS_STRING(repr)) < 0)
return NULL;
return repr;
return _PyBytesWriter_Finish(&writer, p);
error:
_PyBytesWriter_Dealloc(&writer);
return NULL;
}
PyObject *
@ -6291,13 +6310,12 @@ PyUnicode_DecodeRawUnicodeEscape(const char *s,
PyObject *
PyUnicode_AsRawUnicodeEscapeString(PyObject *unicode)
{
PyObject *repr;
char *p;
char *q;
Py_ssize_t expandsize, pos;
Py_ssize_t pos;
int kind;
void *data;
Py_ssize_t len;
_PyBytesWriter writer;
if (!PyUnicode_Check(unicode)) {
PyErr_BadArgument();
@ -6305,28 +6323,29 @@ PyUnicode_AsRawUnicodeEscapeString(PyObject *unicode)
}
if (PyUnicode_READY(unicode) == -1)
return NULL;
_PyBytesWriter_Init(&writer);
kind = PyUnicode_KIND(unicode);
data = PyUnicode_DATA(unicode);
len = PyUnicode_GET_LENGTH(unicode);
/* 4 byte characters can take up 10 bytes, 2 byte characters can take up 6
bytes, and 1 byte characters 4. */
expandsize = kind * 2 + 2;
if (len > PY_SSIZE_T_MAX / expandsize)
return PyErr_NoMemory();
p = _PyBytesWriter_Alloc(&writer, len);
if (p == NULL)
goto error;
writer.overallocate = 1;
repr = PyBytes_FromStringAndSize(NULL, expandsize * len);
if (repr == NULL)
return NULL;
if (len == 0)
return repr;
p = q = PyBytes_AS_STRING(repr);
for (pos = 0; pos < len; pos++) {
Py_UCS4 ch = PyUnicode_READ(kind, data, pos);
/* Map 32-bit characters to '\Uxxxxxxxx' */
if (ch >= 0x10000) {
assert(ch <= MAX_UNICODE);
/* -1: substract 1 preallocated byte */
p = _PyBytesWriter_Prepare(&writer, p, 10-1);
if (p == NULL)
goto error;
*p++ = '\\';
*p++ = 'U';
*p++ = Py_hexdigits[(ch >> 28) & 0xf];
@ -6340,6 +6359,11 @@ PyUnicode_AsRawUnicodeEscapeString(PyObject *unicode)
}
/* Map 16-bit characters to '\uxxxx' */
else if (ch >= 256) {
/* -1: substract 1 preallocated byte */
p = _PyBytesWriter_Prepare(&writer, p, 6-1);
if (p == NULL)
goto error;
*p++ = '\\';
*p++ = 'u';
*p++ = Py_hexdigits[(ch >> 12) & 0xf];
@ -6352,10 +6376,11 @@ PyUnicode_AsRawUnicodeEscapeString(PyObject *unicode)
*p++ = (char) ch;
}
assert(p > q);
if (_PyBytes_Resize(&repr, p - q) < 0)
return NULL;
return repr;
return _PyBytesWriter_Finish(&writer, p);
error:
_PyBytesWriter_Dealloc(&writer);
return NULL;
}
PyObject *