ref: c2aa8c997aa9f7a6f0bc6cb1ad99cccede44fc72
dir: /sys/src/cmd/python/Python/traceback.c/
/* Traceback implementation */
#include "Python.h"
#include "code.h"
#include "frameobject.h"
#include "structmember.h"
#include "osdefs.h"
#include "traceback.h"
#define OFF(x) offsetof(PyTracebackObject, x)
static struct memberlist tb_memberlist[] = {
{"tb_next", T_OBJECT, OFF(tb_next)},
{"tb_frame", T_OBJECT, OFF(tb_frame)},
{"tb_lasti", T_INT, OFF(tb_lasti)},
{"tb_lineno", T_INT, OFF(tb_lineno)},
{NULL} /* Sentinel */
};
static PyObject *
tb_getattr(PyTracebackObject *tb, char *name)
{
return PyMember_Get((char *)tb, tb_memberlist, name);
}
static void
tb_dealloc(PyTracebackObject *tb)
{
PyObject_GC_UnTrack(tb);
Py_TRASHCAN_SAFE_BEGIN(tb)
Py_XDECREF(tb->tb_next);
Py_XDECREF(tb->tb_frame);
PyObject_GC_Del(tb);
Py_TRASHCAN_SAFE_END(tb)
}
static int
tb_traverse(PyTracebackObject *tb, visitproc visit, void *arg)
{
Py_VISIT(tb->tb_next);
Py_VISIT(tb->tb_frame);
return 0;
}
static void
tb_clear(PyTracebackObject *tb)
{
Py_CLEAR(tb->tb_next);
Py_CLEAR(tb->tb_frame);
}
PyTypeObject PyTraceBack_Type = {
PyObject_HEAD_INIT(&PyType_Type)
0,
"traceback",
sizeof(PyTracebackObject),
0,
(destructor)tb_dealloc, /*tp_dealloc*/
0, /*tp_print*/
(getattrfunc)tb_getattr, /*tp_getattr*/
0, /*tp_setattr*/
0, /*tp_compare*/
0, /*tp_repr*/
0, /*tp_as_number*/
0, /*tp_as_sequence*/
0, /*tp_as_mapping*/
0, /* tp_hash */
0, /* tp_call */
0, /* tp_str */
0, /* tp_getattro */
0, /* tp_setattro */
0, /* tp_as_buffer */
Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC,/* tp_flags */
0, /* tp_doc */
(traverseproc)tb_traverse, /* tp_traverse */
(inquiry)tb_clear, /* tp_clear */
0, /* tp_richcompare */
0, /* tp_weaklistoffset */
0, /* tp_iter */
0, /* tp_iternext */
0, /* tp_methods */
0, /* tp_members */
0, /* tp_getset */
0, /* tp_base */
0, /* tp_dict */
};
static PyTracebackObject *
newtracebackobject(PyTracebackObject *next, PyFrameObject *frame)
{
PyTracebackObject *tb;
if ((next != NULL && !PyTraceBack_Check(next)) ||
frame == NULL || !PyFrame_Check(frame)) {
PyErr_BadInternalCall();
return NULL;
}
tb = PyObject_GC_New(PyTracebackObject, &PyTraceBack_Type);
if (tb != NULL) {
Py_XINCREF(next);
tb->tb_next = next;
Py_XINCREF(frame);
tb->tb_frame = frame;
tb->tb_lasti = frame->f_lasti;
tb->tb_lineno = PyCode_Addr2Line(frame->f_code,
frame->f_lasti);
PyObject_GC_Track(tb);
}
return tb;
}
int
PyTraceBack_Here(PyFrameObject *frame)
{
PyThreadState *tstate = PyThreadState_GET();
PyTracebackObject *oldtb = (PyTracebackObject *) tstate->curexc_traceback;
PyTracebackObject *tb = newtracebackobject(oldtb, frame);
if (tb == NULL)
return -1;
tstate->curexc_traceback = (PyObject *)tb;
Py_XDECREF(oldtb);
return 0;
}
static int
tb_displayline(PyObject *f, char *filename, int lineno, char *name)
{
int err = 0;
FILE *xfp;
char linebuf[2000];
int i;
if (filename == NULL || name == NULL)
return -1;
/* This is needed by Emacs' compile command */
#define FMT " File \"%.500s\", line %d, in %.500s\n"
xfp = fopen(filename, "r" PY_STDIOTEXTMODE);
if (xfp == NULL) {
/* Search tail of filename in sys.path before giving up */
PyObject *path;
char *tail = strrchr(filename, SEP);
if (tail == NULL)
tail = filename;
else
tail++;
path = PySys_GetObject("path");
if (path != NULL && PyList_Check(path)) {
Py_ssize_t _npath = PyList_Size(path);
int npath = Py_SAFE_DOWNCAST(_npath, Py_ssize_t, int);
size_t taillen = strlen(tail);
char namebuf[MAXPATHLEN+1];
for (i = 0; i < npath; i++) {
PyObject *v = PyList_GetItem(path, i);
if (v == NULL) {
PyErr_Clear();
break;
}
if (PyString_Check(v)) {
size_t len;
len = PyString_GET_SIZE(v);
if (len + 1 + taillen >= MAXPATHLEN)
continue; /* Too long */
strcpy(namebuf, PyString_AsString(v));
if (strlen(namebuf) != len)
continue; /* v contains '\0' */
if (len > 0 && namebuf[len-1] != SEP)
namebuf[len++] = SEP;
strcpy(namebuf+len, tail);
xfp = fopen(namebuf, "r" PY_STDIOTEXTMODE);
if (xfp != NULL) {
filename = namebuf;
break;
}
}
}
}
}
PyOS_snprintf(linebuf, sizeof(linebuf), FMT, filename, lineno, name);
err = PyFile_WriteString(linebuf, f);
if (xfp == NULL)
return err;
else if (err != 0) {
fclose(xfp);
return err;
}
for (i = 0; i < lineno; i++) {
char* pLastChar = &linebuf[sizeof(linebuf)-2];
do {
*pLastChar = '\0';
if (Py_UniversalNewlineFgets(linebuf, sizeof linebuf, xfp, NULL) == NULL)
break;
/* fgets read *something*; if it didn't get as
far as pLastChar, it must have found a newline
or hit the end of the file; if pLastChar is \n,
it obviously found a newline; else we haven't
yet seen a newline, so must continue */
} while (*pLastChar != '\0' && *pLastChar != '\n');
}
if (i == lineno) {
char *p = linebuf;
while (*p == ' ' || *p == '\t' || *p == '\014')
p++;
err = PyFile_WriteString(" ", f);
if (err == 0) {
err = PyFile_WriteString(p, f);
if (err == 0 && strchr(p, '\n') == NULL)
err = PyFile_WriteString("\n", f);
}
}
fclose(xfp);
return err;
}
static int
tb_printinternal(PyTracebackObject *tb, PyObject *f, int limit)
{
int err = 0;
int depth = 0;
PyTracebackObject *tb1 = tb;
while (tb1 != NULL) {
depth++;
tb1 = tb1->tb_next;
}
while (tb != NULL && err == 0) {
if (depth <= limit) {
err = tb_displayline(f,
PyString_AsString(
tb->tb_frame->f_code->co_filename),
tb->tb_lineno,
PyString_AsString(tb->tb_frame->f_code->co_name));
}
depth--;
tb = tb->tb_next;
if (err == 0)
err = PyErr_CheckSignals();
}
return err;
}
int
PyTraceBack_Print(PyObject *v, PyObject *f)
{
int err;
PyObject *limitv;
int limit = 1000;
if (v == NULL)
return 0;
if (!PyTraceBack_Check(v)) {
PyErr_BadInternalCall();
return -1;
}
limitv = PySys_GetObject("tracebacklimit");
if (limitv && PyInt_Check(limitv)) {
limit = PyInt_AsLong(limitv);
if (limit <= 0)
return 0;
}
err = PyFile_WriteString("Traceback (most recent call last):\n", f);
if (!err)
err = tb_printinternal((PyTracebackObject *)v, f, limit);
return err;
}