Merged revisions 72487-72488,72879 via svnmerge from

svn+ssh://pythondev@svn.python.org/python/trunk

........
  r72487 | jeffrey.yasskin | 2009-05-08 17:51:06 -0400 (Fri, 08 May 2009) | 7 lines

  PyCode_NewEmpty:
  Most uses of PyCode_New found by http://www.google.com/codesearch?q=PyCode_New
  are trying to build an empty code object, usually to put it in a dummy frame
  object. This patch adds a PyCode_NewEmpty wrapper which lets the user specify
  just the filename, function name, and first line number, instead of also
  requiring lots of code internals.
........
  r72488 | jeffrey.yasskin | 2009-05-08 18:23:21 -0400 (Fri, 08 May 2009) | 13 lines

  Issue 5954, PyFrame_GetLineNumber:
  Most uses of PyCode_Addr2Line
  (http://www.google.com/codesearch?q=PyCode_Addr2Line) are just trying to get
  the line number of a specified frame, but there's no way to do that directly.
  Forcing people to go through the code object makes them know more about the
  guts of the interpreter than they should need.

  The remaining uses of PyCode_Addr2Line seem to be getting the line from a
  traceback (for example,
  http://www.google.com/codesearch/p?hl=en#u_9_nDrchrw/pygame-1.7.1release/src/base.c&q=PyCode_Addr2Line),
  which is replaced by the tb_lineno field.  So we may be able to deprecate
  PyCode_Addr2Line entirely for external use.
........
  r72879 | jeffrey.yasskin | 2009-05-23 19:23:01 -0400 (Sat, 23 May 2009) | 14 lines

  Issue #6042:
  lnotab-based tracing is very complicated and isn't documented very well.  There
  were at least 3 comment blocks purporting to document co_lnotab, and none did a
  very good job. This patch unifies them into Objects/lnotab_notes.txt which
  tries to completely capture the current state of affairs.

  I also discovered that we've attached 2 layers of patches to the basic tracing
  scheme. The first layer avoids jumping to instructions that don't start a line,
  to avoid problems in if statements and while loops.  The second layer
  discovered that jumps backward do need to trace at instructions that don't
  start a line, so it added extra lnotab entries for 'while' and 'for' loops, and
  added a special case for backward jumps within the same line. I replaced these
  patches by just treating forward and backward jumps differently.
........

3 files changed, 18 insertions, 76 deletions

diff --git a/Modules/_ctypes/callbacks.c b/Modules/_ctypes/callbacks.c
index 328b10f..6e44080 100644
--- a/Modules/_ctypes/callbacks.c
+++ b/Modules/_ctypes/callbacks.c
@@ -94,41 +94,13 @@ PrintError(char *msg, ...)
 /* after code that pyrex generates */
 void _ctypes_add_traceback(char *funcname, char *filename, int lineno)
 {
-	PyObject *py_srcfile = 0;
-	PyObject *py_funcname = 0;
 	PyObject *py_globals = 0;
-	PyObject *empty_tuple = 0;
-	PyObject *empty_string = 0;
 	PyCodeObject *py_code = 0;
 	PyFrameObject *py_frame = 0;
     
-	py_srcfile = PyUnicode_DecodeFSDefault(filename);
-	if (!py_srcfile) goto bad;
-	py_funcname = PyUnicode_FromString(funcname);
-	if (!py_funcname) goto bad;
 	py_globals = PyDict_New();
 	if (!py_globals) goto bad;
-	empty_tuple = PyTuple_New(0);
-	if (!empty_tuple) goto bad;
-	empty_string = PyBytes_FromString("");
-	if (!empty_string) goto bad;
-	py_code = PyCode_New(
-		0,            /*int argcount,*/
-		0,            /*int kwonlyargcount,*/
-		0,            /*int nlocals,*/
-		0,            /*int stacksize,*/
-		0,            /*int flags,*/
-		empty_string, /*PyObject *code,*/
-		empty_tuple,  /*PyObject *consts,*/
-		empty_tuple,  /*PyObject *names,*/
-		empty_tuple,  /*PyObject *varnames,*/
-		empty_tuple,  /*PyObject *freevars,*/
-		empty_tuple,  /*PyObject *cellvars,*/
-		py_srcfile,   /*PyObject *filename,*/
-		py_funcname,  /*PyObject *name,*/
-		lineno,   /*int firstlineno,*/
-		empty_string  /*PyObject *lnotab*/
-		);
+	py_code = PyCode_NewEmpty(filename, funcname, lineno);
 	if (!py_code) goto bad;
 	py_frame = PyFrame_New(
 		PyThreadState_Get(), /*PyThreadState *tstate,*/
@@ -141,10 +113,6 @@ void _ctypes_add_traceback(char *funcname, char *filename, int lineno)
 	PyTraceBack_Here(py_frame);
   bad:
 	Py_XDECREF(py_globals);
-	Py_XDECREF(py_srcfile);
-	Py_XDECREF(py_funcname);
-	Py_XDECREF(empty_tuple);
-	Py_XDECREF(empty_string);
 	Py_XDECREF(py_code);
 	Py_XDECREF(py_frame);
 }
diff --git a/Modules/_testcapimodule.c b/Modules/_testcapimodule.c
index 5532e07..8dc09ac 100644
--- a/Modules/_testcapimodule.c
+++ b/Modules/_testcapimodule.c
@@ -1446,6 +1446,21 @@ argparsing(PyObject *o, PyObject *args)
 	Py_RETURN_NONE;
 }
 
+/* To test that the result of PyCode_NewEmpty has the right members. */
+static PyObject *
+code_newempty(PyObject *self, PyObject *args)
+{
+	const char *filename;
+	const char *funcname;
+        int firstlineno;
+
+	if (!PyArg_ParseTuple(args, "ssi:code_newempty",
+			      &filename, &funcname, &firstlineno))
+		return NULL;
+
+	return (PyObject *)PyCode_NewEmpty(filename, funcname, firstlineno);
+}
+
 static PyMethodDef TestMethods[] = {
 	{"raise_exception",	raise_exception,		 METH_VARARGS},
 	{"raise_memoryerror",   (PyCFunction)raise_memoryerror,  METH_NOARGS},
@@ -1498,6 +1513,7 @@ static PyMethodDef TestMethods[] = {
 	{"traceback_print", traceback_print, 	         METH_VARARGS},
 	{"exception_print", exception_print, 	         METH_VARARGS},
 	{"argparsing",     argparsing, METH_VARARGS},
+	{"code_newempty", code_newempty, 	         METH_VARARGS},
 	{NULL, NULL} /* sentinel */
 };
 
diff --git a/Modules/pyexpat.c b/Modules/pyexpat.c
index 1b9ffca..4b5652e 100644
--- a/Modules/pyexpat.c
+++ b/Modules/pyexpat.c
@@ -209,53 +209,11 @@ flag_error(xmlparseobject *self)
 static PyCodeObject*
 getcode(enum HandlerTypes slot, char* func_name, int lineno)
 {
-    PyObject *code = NULL;
-    PyObject *name = NULL;
-    PyObject *nulltuple = NULL;
-    PyObject *filename = NULL;
-
     if (handler_info[slot].tb_code == NULL) {
-        code = PyBytes_FromString("");
-        if (code == NULL)
-            goto failed;
-        name = PyUnicode_FromString(func_name);
-        if (name == NULL)
-            goto failed;
-        nulltuple = PyTuple_New(0);
-        if (nulltuple == NULL)
-            goto failed;
-        filename = PyUnicode_DecodeFSDefault(__FILE__);
         handler_info[slot].tb_code =
-            PyCode_New(0,		/* argcount */
-                       0,       /* kwonlyargcount */
-                       0,		/* nlocals */
-                       0,		/* stacksize */
-                       0,		/* flags */
-                       code,		/* code */
-                       nulltuple,	/* consts */
-                       nulltuple,	/* names */
-                       nulltuple,	/* varnames */
-#if PYTHON_API_VERSION >= 1010
-                       nulltuple,	/* freevars */
-                       nulltuple,	/* cellvars */
-#endif
-                       filename,	/* filename */
-                       name,		/* name */
-                       lineno,		/* firstlineno */
-                       code		/* lnotab */
-                       );
-        if (handler_info[slot].tb_code == NULL)
-            goto failed;
-        Py_DECREF(code);
-        Py_DECREF(nulltuple);
-        Py_DECREF(filename);
-        Py_DECREF(name);
+            PyCode_NewEmpty(__FILE__, func_name, lineno);
     }
     return handler_info[slot].tb_code;
- failed:
-    Py_XDECREF(code);
-    Py_XDECREF(name);
-    return NULL;
 }
 
 #ifdef FIX_TRACE