From e96ec6810184f5daacb2d47ab8801365c99bb206 Mon Sep 17 00:00:00 2001 From: Antoine Pitrou Date: Sat, 23 Jul 2011 21:46:35 +0200 Subject: Issue #12591: Allow io.TextIOWrapper to work with raw IO objects (without a read1() method), and add an undocumented *write_through* parameter to mandate unbuffered writes. --- Lib/_pyio.py | 8 ++++++-- Lib/test/test_io.py | 21 +++++++++++++++++++++ Misc/NEWS | 4 ++++ Modules/_io/textio.c | 20 ++++++++++++++------ 4 files changed, 45 insertions(+), 8 deletions(-) diff --git a/Lib/_pyio.py b/Lib/_pyio.py index b79d5fc..78c6d95 100644 --- a/Lib/_pyio.py +++ b/Lib/_pyio.py @@ -1472,7 +1472,7 @@ class TextIOWrapper(TextIOBase): _CHUNK_SIZE = 2048 def __init__(self, buffer, encoding=None, errors=None, newline=None, - line_buffering=False): + line_buffering=False, write_through=False): if newline is not None and not isinstance(newline, str): raise TypeError("illegal newline type: %r" % (type(newline),)) if newline not in (None, "", "\n", "\r", "\r\n"): @@ -1515,6 +1515,7 @@ class TextIOWrapper(TextIOBase): self._decoded_chars_used = 0 # offset into _decoded_chars for read() self._snapshot = None # info for reconstructing decoder state self._seekable = self._telling = self.buffer.seekable() + self._has_read1 = hasattr(self.buffer, 'read1') if self._seekable and self.writable(): position = self.buffer.tell() @@ -1680,7 +1681,10 @@ class TextIOWrapper(TextIOBase): # len(dec_buffer) bytes ago with decoder state (b'', dec_flags). # Read a chunk, decode it, and put the result in self._decoded_chars. - input_chunk = self.buffer.read1(self._CHUNK_SIZE) + if self._has_read1: + input_chunk = self.buffer.read1(self._CHUNK_SIZE) + else: + input_chunk = self.buffer.read(self._CHUNK_SIZE) eof = not input_chunk self._set_decoded_chars(self._decoder.decode(input_chunk, eof)) diff --git a/Lib/test/test_io.py b/Lib/test/test_io.py index 39fda2b..0ca621c 100644 --- a/Lib/test/test_io.py +++ b/Lib/test/test_io.py @@ -2307,6 +2307,27 @@ class TextIOWrapperTest(unittest.TestCase): with self.assertRaises(AttributeError): txt.buffer = buf + def test_rawio(self): + # Issue #12591: TextIOWrapper must work with raw I/O objects, so + # that subprocess.Popen() can have the required unbuffered + # semantics with universal_newlines=True. + raw = self.MockRawIO([b'abc', b'def', b'ghi\njkl\nopq\n']) + txt = self.TextIOWrapper(raw, encoding='ascii', newline='\n') + # Reads + self.assertEqual(txt.read(4), 'abcd') + self.assertEqual(txt.readline(), 'efghi\n') + self.assertEqual(list(txt), ['jkl\n', 'opq\n']) + + def test_rawio_write_through(self): + # Issue #12591: with write_through=True, writes don't need a flush + raw = self.MockRawIO([b'abc', b'def', b'ghi\njkl\nopq\n']) + txt = self.TextIOWrapper(raw, encoding='ascii', newline='\n', + write_through=True) + txt.write('1') + txt.write('23\n4') + txt.write('5') + self.assertEqual(b''.join(raw._write_stack), b'123\n45') + class CTextIOWrapperTest(TextIOWrapperTest): def test_initialization(self): diff --git a/Misc/NEWS b/Misc/NEWS index 8d11ca4..2eea1be 100644 --- a/Misc/NEWS +++ b/Misc/NEWS @@ -37,6 +37,10 @@ Core and Builtins Library ------- +- Issue #12591: Allow io.TextIOWrapper to work with raw IO objects (without + a read1() method), and add an undocumented *write_through* parameter to + mandate unbuffered writes. + - Issue #10883: Fix socket leaks in urllib.request when using FTP. - Issue #12592: Make Python build on OpenBSD 5 (and future major releases). diff --git a/Modules/_io/textio.c b/Modules/_io/textio.c index abdbeb7..9c5f441 100644 --- a/Modules/_io/textio.c +++ b/Modules/_io/textio.c @@ -653,10 +653,12 @@ typedef struct PyObject *errors; const char *writenl; /* utf-8 encoded, NULL stands for \n */ char line_buffering; + char write_through; char readuniversal; char readtranslate; char writetranslate; char seekable; + char has_read1; char telling; char deallocating; /* Specialized encoding func (see below) */ @@ -809,13 +811,13 @@ static int textiowrapper_init(textio *self, PyObject *args, PyObject *kwds) { char *kwlist[] = {"buffer", "encoding", "errors", - "newline", "line_buffering", + "newline", "line_buffering", "write_through", NULL}; PyObject *buffer, *raw; char *encoding = NULL; char *errors = NULL; char *newline = NULL; - int line_buffering = 0; + int line_buffering = 0, write_through = 0; _PyIO_State *state = IO_STATE; PyObject *res; @@ -823,9 +825,9 @@ textiowrapper_init(textio *self, PyObject *args, PyObject *kwds) self->ok = 0; self->detached = 0; - if (!PyArg_ParseTupleAndKeywords(args, kwds, "O|zzzi:fileio", + if (!PyArg_ParseTupleAndKeywords(args, kwds, "O|zzzii:fileio", kwlist, &buffer, &encoding, &errors, - &newline, &line_buffering)) + &newline, &line_buffering, &write_through)) return -1; if (newline && newline[0] != '\0' @@ -930,6 +932,7 @@ textiowrapper_init(textio *self, PyObject *args, PyObject *kwds) self->chunk_size = 8192; self->readuniversal = (newline == NULL || newline[0] == '\0'); self->line_buffering = line_buffering; + self->write_through = write_through; self->readtranslate = (newline == NULL); if (newline) { self->readnl = PyUnicode_FromString(newline); @@ -1039,6 +1042,8 @@ textiowrapper_init(textio *self, PyObject *args, PyObject *kwds) self->seekable = self->telling = PyObject_IsTrue(res); Py_DECREF(res); + self->has_read1 = PyObject_HasAttrString(buffer, "read1"); + self->encoding_start_of_stream = 0; if (self->seekable && self->encoder) { PyObject *cookieObj; @@ -1282,7 +1287,9 @@ textiowrapper_write(textio *self, PyObject *args) text = newtext; } - if (self->line_buffering && + if (self->write_through) + needflush = 1; + else if (self->line_buffering && (haslf || findchar(PyUnicode_AS_UNICODE(text), PyUnicode_GET_SIZE(text), '\r'))) @@ -1429,7 +1436,8 @@ textiowrapper_read_chunk(textio *self) if (chunk_size == NULL) goto fail; input_chunk = PyObject_CallMethodObjArgs(self->buffer, - _PyIO_str_read1, chunk_size, NULL); + (self->has_read1 ? _PyIO_str_read1: _PyIO_str_read), + chunk_size, NULL); Py_DECREF(chunk_size); if (input_chunk == NULL) goto fail; -- cgit v0.12