Issue #4705: Fix the -u ("unbuffered binary stdout and stderr") command-line
flag to work properly. Furthermore, when specifying -u, the text stdout
and stderr streams have line-by-line buffering enabled (the default being
to buffer arbitrary chunks of data). Patch by Victor Stinner, test by me.
diff --git a/Python/pythonrun.c b/Python/pythonrun.c
index c5f7e23..8a1af3b 100644
--- a/Python/pythonrun.c
+++ b/Python/pythonrun.c
@@ -88,6 +88,7 @@
int Py_FrozenFlag; /* Needed by getpath.c */
int Py_IgnoreEnvironmentFlag; /* e.g. PYTHONPATH, PYTHONHOME */
int Py_NoUserSiteDirectory = 0; /* for -s and site.py */
+int Py_UnbufferedStdioFlag = 0; /* Unbuffered binary std{in,out,err} */
/* PyModule_GetWarningsModule is no longer necessary as of 2.6
since _warnings is builtin. This API should not be used. */
@@ -728,6 +729,75 @@
}
}
+static PyObject*
+create_stdio(PyObject* io,
+ int fd, int write_mode, char* name,
+ char* encoding, char* errors)
+{
+ PyObject *buf = NULL, *stream = NULL, *text = NULL, *raw = NULL;
+ const char* mode;
+ const PyObject *line_buffering;
+ int buffering;
+
+ if (Py_UnbufferedStdioFlag)
+ buffering = 0;
+ else
+ buffering = -1;
+ if (write_mode)
+ mode = "wb";
+ else
+ mode = "rb";
+ buf = PyObject_CallMethod(io, "open", "isiOOOi",
+ fd, mode, buffering,
+ Py_None, Py_None, Py_None, 0);
+ if (buf == NULL)
+ goto error;
+
+ if (!Py_UnbufferedStdioFlag) {
+ raw = PyObject_GetAttrString(buf, "raw");
+ if (raw == NULL)
+ goto error;
+ }
+ else {
+ raw = buf;
+ Py_INCREF(raw);
+ }
+
+ text = PyUnicode_FromString(name);
+ if (text == NULL || PyObject_SetAttrString(raw, "_name", text) < 0)
+ goto error;
+ Py_CLEAR(raw);
+ Py_CLEAR(text);
+
+ if (Py_UnbufferedStdioFlag)
+ line_buffering = Py_True;
+ else
+ line_buffering = Py_False;
+ stream = PyObject_CallMethod(io, "TextIOWrapper", "OsssO",
+ buf, encoding, errors,
+ "\n", line_buffering);
+ Py_CLEAR(buf);
+ if (stream == NULL)
+ goto error;
+
+ if (write_mode)
+ mode = "w";
+ else
+ mode = "r";
+ text = PyUnicode_FromString(mode);
+ if (!text || PyObject_SetAttrString(stream, "mode", text) < 0)
+ goto error;
+ Py_CLEAR(text);
+ return stream;
+
+error:
+ Py_XDECREF(buf);
+ Py_XDECREF(stream);
+ Py_XDECREF(text);
+ Py_XDECREF(raw);
+ return NULL;
+}
+
/* Initialize sys.stdin, stdout, stderr and builtins.open */
static int
initstdio(void)
@@ -794,10 +864,9 @@
#endif
}
else {
- if (!(std = PyFile_FromFd(fd, "<stdin>", "r", -1, encoding,
- errors, "\n", 0))) {
+ std = create_stdio(iomod, fd, 0, "<stdin>", encoding, errors);
+ if (std == NULL)
goto error;
- }
} /* if (fd < 0) */
PySys_SetObject("__stdin__", std);
PySys_SetObject("stdin", std);
@@ -814,10 +883,9 @@
#endif
}
else {
- if (!(std = PyFile_FromFd(fd, "<stdout>", "w", -1, encoding,
- errors, "\n", 0))) {
+ std = create_stdio(iomod, fd, 1, "<stdout>", encoding, errors);
+ if (std == NULL)
goto error;
- }
} /* if (fd < 0) */
PySys_SetObject("__stdout__", std);
PySys_SetObject("stdout", std);
@@ -835,10 +903,9 @@
#endif
}
else {
- if (!(std = PyFile_FromFd(fd, "<stderr>", "w", -1, encoding,
- "backslashreplace", "\n", 0))) {
+ std = create_stdio(iomod, fd, 1, "<stderr>", encoding, "backslashreplace");
+ if (std == NULL)
goto error;
- }
} /* if (fd < 0) */
/* Same as hack above, pre-import stderr's codec to avoid recursion