static void
plpython_error_callback(void *arg)
{
PLyExecutionContext *exec_ctx = (PLyExecutionContext *) arg;
if (exec_ctx->curr_proc)
errcontext("PL/Python function \"%s\"",
PLy_procedure_name(exec_ctx->curr_proc));
}
/*
* Extract a Python traceback from the given exception data.
*
* The exception error message is returned in xmsg, the traceback in
* tbmsg (both as palloc'd strings) and the traceback depth in
* tb_depth.
*
* We release refcounts on all the Python objects in the traceback stack,
* but not on e or v.
*/
static void
PLy_traceback(PyObject *e, PyObject *v, PyObject *tb,
char **xmsg, char **tbmsg, int *tb_depth)
{
PyObject *e_type_o;
PyObject *e_module_o;
char *e_type_s = NULL;
char *e_module_s = NULL;
PyObject *vob = NULL;
char *vstr;
StringInfoData xstr;
StringInfoData tbstr;
/*
* if no exception, return nulls
*/
if (e == NULL)
{
*xmsg = NULL;
*tbmsg = NULL;
*tb_depth = 0;
return;
}
/*
* Format the exception and its value and put it in xmsg.
*/
e_type_o = PyObject_GetAttrString(e, "__name__");
e_module_o = PyObject_GetAttrString(e, "__module__");
if (e_type_o)
e_type_s = PyString_AsString(e_type_o);
if (e_type_s)
e_module_s = PyString_AsString(e_module_o);
if (v && ((vob = PyObject_Str(v)) != NULL))
vstr = PyString_AsString(vob);
else
vstr = "unknown";
initStringInfo(&xstr);
if (!e_type_s || !e_module_s)
{
if (PyString_Check(e))
/* deprecated string exceptions */
appendStringInfoString(&xstr, PyString_AsString(e));
else
/* shouldn't happen */
appendStringInfoString(&xstr, "unrecognized exception");
}
/* mimics behavior of traceback.format_exception_only */
else if (strcmp(e_module_s, "builtins") == 0
|| strcmp(e_module_s, "__main__") == 0
|| strcmp(e_module_s, "exceptions") == 0)
appendStringInfo(&xstr, "%s", e_type_s);
else
appendStringInfo(&xstr, "%s.%s", e_module_s, e_type_s);
appendStringInfo(&xstr, ": %s", vstr);
*xmsg = xstr.data;
/*
* Now format the traceback and put it in tbmsg.
*/
*tb_depth = 0;
initStringInfo(&tbstr);
/* Mimick Python traceback reporting as close as possible. */
appendStringInfoString(&tbstr, "Traceback (most recent call last):");
while (tb != NULL && tb != Py_None)
{
PyObject *volatile tb_prev = NULL;
PyObject *volatile frame = NULL;
PyObject *volatile code = NULL;
PyObject *volatile name = NULL;
PyObject *volatile lineno = NULL;
PyObject *volatile filename = NULL;
PG_TRY();
{
/*
* Ancient versions of Python (circa 2.3) contain a bug whereby
* the fetches below can fail if the error indicator is set.
*/
PyErr_Clear();
lineno = PyObject_GetAttrString(tb, "tb_lineno");
if (lineno == NULL)
elog(ERROR, "could not get line number from Python traceback");
frame = PyObject_GetAttrString(tb, "tb_frame");
if (frame == NULL)
elog(ERROR, "could not get frame from Python traceback");
code = PyObject_GetAttrString(frame, "f_code");
if (code == NULL)
elog(ERROR, "could not get code object from Python frame");
name = PyObject_GetAttrString(code, "co_name");
if (name == NULL)
elog(ERROR, "could not get function name from Python code object");
filename = PyObject_GetAttrString(code, "co_filename");
if (filename == NULL)
elog(ERROR, "could not get file name from Python code object");
}
PG_CATCH();
{
Py_XDECREF(frame);
Py_XDECREF(code);
Py_XDECREF(name);
Py_XDECREF(lineno);
Py_XDECREF(filename);
PG_RE_THROW();
}
PG_END_TRY();
/* The first frame always points at <module>, skip it. */
if (*tb_depth > 0)
{
PLyExecutionContext *exec_ctx = PLy_current_execution_context();
char *proname;
char *fname;
char *line;
char *plain_filename;
long plain_lineno;
/*
* The second frame points at the internal function, but to mimick
* Python error reporting we want to say <module>.
*/
if (*tb_depth == 1)
fname = "<module>";
else
fname = PyString_AsString(name);
proname = PLy_procedure_name(exec_ctx->curr_proc);
plain_filename = PyString_AsString(filename);
plain_lineno = PyInt_AsLong(lineno);
if (proname == NULL)
appendStringInfo(
&tbstr, "\n PL/Python anonymous code block, line %ld, in %s",
plain_lineno - 1, fname);
else
appendStringInfo(
&tbstr, "\n PL/Python function \"%s\", line %ld, in %s",
proname, plain_lineno - 1, fname);
/*
* function code object was compiled with "<string>" as the
* filename
*/
if (exec_ctx->curr_proc && plain_filename != NULL &&
strcmp(plain_filename, "<string>") == 0)
{
/*
* If we know the current procedure, append the exact line
* from the source, again mimicking Python's traceback.py
* module behavior. We could store the already line-split
* source to avoid splitting it every time, but producing a
* traceback is not the most important scenario to optimize
* for. But we do not go as far as traceback.py in reading
* the source of imported modules.
*/
line = get_source_line(exec_ctx->curr_proc->src, plain_lineno);
if (line)
{
appendStringInfo(&tbstr, "\n %s", line);
pfree(line);
}
}
}
Py_DECREF(frame);
Py_DECREF(code);
Py_DECREF(name);
Py_DECREF(lineno);
Py_DECREF(filename);
/* Release the current frame and go to the next one. */
tb_prev = tb;
tb = PyObject_GetAttrString(tb, "tb_next");
Assert(tb_prev != Py_None);
Py_DECREF(tb_prev);
if (tb == NULL)
elog(ERROR, "could not traverse Python traceback");
(*tb_depth)++;
}
/* Return the traceback. */
*tbmsg = tbstr.data;
Py_XDECREF(e_type_o);
Py_XDECREF(e_module_o);
Py_XDECREF(vob);
}
