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/* Traceback implementation */
#include "Python.h"
#include "code.h"
#include "frameobject.h" // PyFrame_GetBack()
#include "structmember.h" // PyMemberDef
#include "osdefs.h" // SEP
#ifdef HAVE_FCNTL_H
#include
#endif
#define OFF(x) offsetof(PyTracebackObject, x)
#define PUTS(fd, str) _Py_write_noraise(fd, str, (int)strlen(str))
#define MAX_STRING_LENGTH 500
#define MAX_FRAME_DEPTH 100
#define MAX_NTHREADS 100
/* Function from Parser/tokenizer.c */
extern char * PyTokenizer_FindEncodingFilename(int, PyObject *);
_Py_IDENTIFIER(TextIOWrapper);
_Py_IDENTIFIER(close);
_Py_IDENTIFIER(open);
_Py_IDENTIFIER(path);
/*[clinic input]
class TracebackType "PyTracebackObject *" "&PyTraceback_Type"
[clinic start generated code]*/
/*[clinic end generated code: output=da39a3ee5e6b4b0d input=928fa06c10151120]*/
#include "clinic/traceback.c.h"
static PyObject *
tb_create_raw(PyTracebackObject *next, PyFrameObject *frame, int lasti,
int lineno)
{
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 = lasti;
tb->tb_lineno = lineno;
PyObject_GC_Track(tb);
}
return (PyObject *)tb;
}
/*[clinic input]
@classmethod
TracebackType.__new__ as tb_new
tb_next: object
tb_frame: object(type='PyFrameObject *', subclass_of='&PyFrame_Type')
tb_lasti: int
tb_lineno: int
Create a new traceback object.
[clinic start generated code]*/
static PyObject *
tb_new_impl(PyTypeObject *type, PyObject *tb_next, PyFrameObject *tb_frame,
int tb_lasti, int tb_lineno)
/*[clinic end generated code: output=fa077debd72d861a input=01cbe8ec8783fca7]*/
{
if (tb_next == Py_None) {
tb_next = NULL;
} else if (!PyTraceBack_Check(tb_next)) {
return PyErr_Format(PyExc_TypeError,
"expected traceback object or None, got '%s'",
Py_TYPE(tb_next)->tp_name);
}
return tb_create_raw((PyTracebackObject *)tb_next, tb_frame, tb_lasti,
tb_lineno);
}
static PyObject *
tb_dir(PyTracebackObject *self, PyObject *Py_UNUSED(ignored))
{
return Py_BuildValue("[ssss]", "tb_frame", "tb_next",
"tb_lasti", "tb_lineno");
}
static PyObject *
tb_next_get(PyTracebackObject *self, void *Py_UNUSED(_))
{
PyObject* ret = (PyObject*)self->tb_next;
if (!ret) {
ret = Py_None;
}
Py_INCREF(ret);
return ret;
}
static int
tb_next_set(PyTracebackObject *self, PyObject *new_next, void *Py_UNUSED(_))
{
if (!new_next) {
PyErr_Format(PyExc_TypeError, "can't delete tb_next attribute");
return -1;
}
/* We accept None or a traceback object, and map None -> NULL (inverse of
tb_next_get) */
if (new_next == Py_None) {
new_next = NULL;
} else if (!PyTraceBack_Check(new_next)) {
PyErr_Format(PyExc_TypeError,
"expected traceback object, got '%s'",
Py_TYPE(new_next)->tp_name);
return -1;
}
/* Check for loops */
PyTracebackObject *cursor = (PyTracebackObject *)new_next;
while (cursor) {
if (cursor == self) {
PyErr_Format(PyExc_ValueError, "traceback loop detected");
return -1;
}
cursor = cursor->tb_next;
}
PyObject *old_next = (PyObject*)self->tb_next;
Py_XINCREF(new_next);
self->tb_next = (PyTracebackObject *)new_next;
Py_XDECREF(old_next);
return 0;
}
static PyMethodDef tb_methods[] = {
{"__dir__", (PyCFunction)tb_dir, METH_NOARGS},
{NULL, NULL, 0, NULL},
};
static PyMemberDef tb_memberlist[] = {
{"tb_frame", T_OBJECT, OFF(tb_frame), READONLY},
{"tb_lasti", T_INT, OFF(tb_lasti), READONLY},
{"tb_lineno", T_INT, OFF(tb_lineno), READONLY},
{NULL} /* Sentinel */
};
static PyGetSetDef tb_getsetters[] = {
{"tb_next", (getter)tb_next_get, (setter)tb_next_set, NULL, NULL},
{NULL} /* Sentinel */
};
static void
tb_dealloc(PyTracebackObject *tb)
{
PyObject_GC_UnTrack(tb);
Py_TRASHCAN_BEGIN(tb, tb_dealloc)
Py_XDECREF(tb->tb_next);
Py_XDECREF(tb->tb_frame);
PyObject_GC_Del(tb);
Py_TRASHCAN_END
}
static int
tb_traverse(PyTracebackObject *tb, visitproc visit, void *arg)
{
Py_VISIT(tb->tb_next);
Py_VISIT(tb->tb_frame);
return 0;
}
static int
tb_clear(PyTracebackObject *tb)
{
Py_CLEAR(tb->tb_next);
Py_CLEAR(tb->tb_frame);
return 0;
}
PyTypeObject PyTraceBack_Type = {
PyVarObject_HEAD_INIT(&PyType_Type, 0)
"traceback",
sizeof(PyTracebackObject),
0,
(destructor)tb_dealloc, /*tp_dealloc*/
0, /*tp_vectorcall_offset*/
0, /*tp_getattr*/
0, /*tp_setattr*/
0, /*tp_as_async*/
0, /*tp_repr*/
0, /*tp_as_number*/
0, /*tp_as_sequence*/
0, /*tp_as_mapping*/
0, /* tp_hash */
0, /* tp_call */
0, /* tp_str */
PyObject_GenericGetAttr, /* tp_getattro */
0, /* tp_setattro */
0, /* tp_as_buffer */
Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC,/* tp_flags */
tb_new__doc__, /* tp_doc */
(traverseproc)tb_traverse, /* tp_traverse */
(inquiry)tb_clear, /* tp_clear */
0, /* tp_richcompare */
0, /* tp_weaklistoffset */
0, /* tp_iter */
0, /* tp_iternext */
tb_methods, /* tp_methods */
tb_memberlist, /* tp_members */
tb_getsetters, /* tp_getset */
0, /* tp_base */
0, /* tp_dict */
0, /* tp_descr_get */
0, /* tp_descr_set */
0, /* tp_dictoffset */
0, /* tp_init */
0, /* tp_alloc */
tb_new, /* tp_new */
};
PyObject*
_PyTraceBack_FromFrame(PyObject *tb_next, PyFrameObject *frame)
{
assert(tb_next == NULL || PyTraceBack_Check(tb_next));
assert(frame != NULL);
return tb_create_raw((PyTracebackObject *)tb_next, frame, frame->f_lasti,
PyFrame_GetLineNumber(frame));
}
int
PyTraceBack_Here(PyFrameObject *frame)
{
PyObject *exc, *val, *tb, *newtb;
PyErr_Fetch(&exc, &val, &tb);
newtb = _PyTraceBack_FromFrame(tb, frame);
if (newtb == NULL) {
_PyErr_ChainExceptions(exc, val, tb);
return -1;
}
PyErr_Restore(exc, val, newtb);
Py_XDECREF(tb);
return 0;
}
/* Insert a frame into the traceback for (funcname, filename, lineno). */
void _PyTraceback_Add(const char *funcname, const char *filename, int lineno)
{
PyObject *globals;
PyCodeObject *code;
PyFrameObject *frame;
PyObject *exc, *val, *tb;
/* Save and clear the current exception. Python functions must not be
called with an exception set. Calling Python functions happens when
the codec of the filesystem encoding is implemented in pure Python. */
PyErr_Fetch(&exc, &val, &tb);
globals = PyDict_New();
if (!globals)
goto error;
code = PyCode_NewEmpty(filename, funcname, lineno);
if (!code) {
Py_DECREF(globals);
goto error;
}
frame = PyFrame_New(PyThreadState_Get(), code, globals, NULL);
Py_DECREF(globals);
Py_DECREF(code);
if (!frame)
goto error;
frame->f_lineno = lineno;
PyErr_Restore(exc, val, tb);
PyTraceBack_Here(frame);
Py_DECREF(frame);
return;
error:
_PyErr_ChainExceptions(exc, val, tb);
}
static PyObject *
_Py_FindSourceFile(PyObject *filename, char* namebuf, size_t namelen, PyObject *io)
{
Py_ssize_t i;
PyObject *binary;
PyObject *v;
Py_ssize_t npath;
size_t taillen;
PyObject *syspath;
PyObject *path;
const char* tail;
PyObject *filebytes;
const char* filepath;
Py_ssize_t len;
PyObject* result;
filebytes = PyUnicode_EncodeFSDefault(filename);
if (filebytes == NULL) {
PyErr_Clear();
return NULL;
}
filepath = PyBytes_AS_STRING(filebytes);
/* Search tail of filename in sys.path before giving up */
tail = strrchr(filepath, SEP);
if (tail == NULL)
tail = filepath;
else
tail++;
taillen = strlen(tail);
syspath = _PySys_GetObjectId(&PyId_path);
if (syspath == NULL || !PyList_Check(syspath))
goto error;
npath = PyList_Size(syspath);
for (i = 0; i < npath; i++) {
v = PyList_GetItem(syspath, i);
if (v == NULL) {
PyErr_Clear();
break;
}
if (!PyUnicode_Check(v))
continue;
path = PyUnicode_EncodeFSDefault(v);
if (path == NULL) {
PyErr_Clear();
continue;
}
len = PyBytes_GET_SIZE(path);
if (len + 1 + (Py_ssize_t)taillen >= (Py_ssize_t)namelen - 1) {
Py_DECREF(path);
continue; /* Too long */
}
strcpy(namebuf, PyBytes_AS_STRING(path));
Py_DECREF(path);
if (strlen(namebuf) != (size_t)len)
continue; /* v contains '\0' */
if (len > 0 && namebuf[len-1] != SEP)
namebuf[len++] = SEP;
strcpy(namebuf+len, tail);
binary = _PyObject_CallMethodId(io, &PyId_open, "ss", namebuf, "rb");
if (binary != NULL) {
result = binary;
goto finally;
}
PyErr_Clear();
}
goto error;
error:
result = NULL;
finally:
Py_DECREF(filebytes);
return result;
}
int
_Py_DisplaySourceLine(PyObject *f, PyObject *filename, int lineno, int indent)
{
int err = 0;
int fd;
int i;
char *found_encoding;
const char *encoding;
PyObject *io;
PyObject *binary;
PyObject *fob = NULL;
PyObject *lineobj = NULL;
PyObject *res;
char buf[MAXPATHLEN+1];
int kind;
const void *data;
/* open the file */
if (filename == NULL)
return 0;
io = PyImport_ImportModuleNoBlock("io");
if (io == NULL)
return -1;
binary = _PyObject_CallMethodId(io, &PyId_open, "Os", filename, "rb");
if (binary == NULL) {
PyErr_Clear();
binary = _Py_FindSourceFile(filename, buf, sizeof(buf), io);
if (binary == NULL) {
Py_DECREF(io);
return -1;
}
}
/* use the right encoding to decode the file as unicode */
fd = PyObject_AsFileDescriptor(binary);
if (fd < 0) {
Py_DECREF(io);
Py_DECREF(binary);
return 0;
}
found_encoding = PyTokenizer_FindEncodingFilename(fd, filename);
if (found_encoding == NULL)
PyErr_Clear();
encoding = (found_encoding != NULL) ? found_encoding : "utf-8";
/* Reset position */
if (lseek(fd, 0, SEEK_SET) == (off_t)-1) {
Py_DECREF(io);
Py_DECREF(binary);
PyMem_FREE(found_encoding);
return 0;
}
fob = _PyObject_CallMethodId(io, &PyId_TextIOWrapper, "Os", binary, encoding);
Py_DECREF(io);
PyMem_FREE(found_encoding);
if (fob == NULL) {
PyErr_Clear();
res = _PyObject_CallMethodIdNoArgs(binary, &PyId_close);
Py_DECREF(binary);
if (res)
Py_DECREF(res);
else
PyErr_Clear();
return 0;
}
Py_DECREF(binary);
/* get the line number lineno */
for (i = 0; i < lineno; i++) {
Py_XDECREF(lineobj);
lineobj = PyFile_GetLine(fob, -1);
if (!lineobj) {
PyErr_Clear();
err = -1;
break;
}
}
res = _PyObject_CallMethodIdNoArgs(fob, &PyId_close);
if (res)
Py_DECREF(res);
else
PyErr_Clear();
Py_DECREF(fob);
if (!lineobj || !PyUnicode_Check(lineobj)) {
Py_XDECREF(lineobj);
return err;
}
/* remove the indentation of the line */
kind = PyUnicode_KIND(lineobj);
data = PyUnicode_DATA(lineobj);
for (i=0; i < PyUnicode_GET_LENGTH(lineobj); i++) {
Py_UCS4 ch = PyUnicode_READ(kind, data, i);
if (ch != ' ' && ch != '\t' && ch != '\014')
break;
}
if (i) {
PyObject *truncated;
truncated = PyUnicode_Substring(lineobj, i, PyUnicode_GET_LENGTH(lineobj));
if (truncated) {
Py_DECREF(lineobj);
lineobj = truncated;
} else {
PyErr_Clear();
}
}
/* Write some spaces before the line */
strcpy(buf, " ");
assert (strlen(buf) == 10);
while (indent > 0) {
if (indent < 10)
buf[indent] = '\0';
err = PyFile_WriteString(buf, f);
if (err != 0)
break;
indent -= 10;
}
/* finally display the line */
if (err == 0)
err = PyFile_WriteObject(lineobj, f, Py_PRINT_RAW);
Py_DECREF(lineobj);
if (err == 0)
err = PyFile_WriteString("\n", f);
return err;
}
static int
tb_displayline(PyObject *f, PyObject *filename, int lineno, PyObject *name)
{
int err;
PyObject *line;
if (filename == NULL || name == NULL)
return -1;
line = PyUnicode_FromFormat(" File \"%U\", line %d, in %U\n",
filename, lineno, name);
if (line == NULL)
return -1;
err = PyFile_WriteObject(line, f, Py_PRINT_RAW);
Py_DECREF(line);
if (err != 0)
return err;
/* ignore errors since we can't report them, can we? */
if (_Py_DisplaySourceLine(f, filename, lineno, 4))
PyErr_Clear();
return err;
}
static const int TB_RECURSIVE_CUTOFF = 3; // Also hardcoded in traceback.py.
static int
tb_print_line_repeated(PyObject *f, long cnt)
{
cnt -= TB_RECURSIVE_CUTOFF;
PyObject *line = PyUnicode_FromFormat(
(cnt > 1)
? " [Previous line repeated %ld more times]\n"
: " [Previous line repeated %ld more time]\n",
cnt);
if (line == NULL) {
return -1;
}
int err = PyFile_WriteObject(line, f, Py_PRINT_RAW);
Py_DECREF(line);
return err;
}
static int
tb_printinternal(PyTracebackObject *tb, PyObject *f, long limit)
{
int err = 0;
Py_ssize_t depth = 0;
PyObject *last_file = NULL;
int last_line = -1;
PyObject *last_name = NULL;
long cnt = 0;
PyTracebackObject *tb1 = tb;
while (tb1 != NULL) {
depth++;
tb1 = tb1->tb_next;
}
while (tb != NULL && depth > limit) {
depth--;
tb = tb->tb_next;
}
while (tb != NULL && err == 0) {
PyCodeObject *code = PyFrame_GetCode(tb->tb_frame);
if (last_file == NULL ||
code->co_filename != last_file ||
last_line == -1 || tb->tb_lineno != last_line ||
last_name == NULL || code->co_name != last_name) {
if (cnt > TB_RECURSIVE_CUTOFF) {
err = tb_print_line_repeated(f, cnt);
}
last_file = code->co_filename;
last_line = tb->tb_lineno;
last_name = code->co_name;
cnt = 0;
}
cnt++;
if (err == 0 && cnt co_filename, tb->tb_lineno,
code->co_name);
if (err == 0) {
err = PyErr_CheckSignals();
}
}
Py_DECREF(code);
tb = tb->tb_next;
}
if (err == 0 && cnt > TB_RECURSIVE_CUTOFF) {
err = tb_print_line_repeated(f, cnt);
}
return err;
}
#define PyTraceBack_LIMIT 1000
int
PyTraceBack_Print(PyObject *v, PyObject *f)
{
int err;
PyObject *limitv;
long limit = PyTraceBack_LIMIT;
if (v == NULL)
return 0;
if (!PyTraceBack_Check(v)) {
PyErr_BadInternalCall();
return -1;
}
limitv = PySys_GetObject("tracebacklimit");
if (limitv && PyLong_Check(limitv)) {
int overflow;
limit = PyLong_AsLongAndOverflow(limitv, &overflow);
if (overflow > 0) {
limit = LONG_MAX;
}
else if (limit = buffer);
*ptr = '0' + (value % 10);
value /= 10;
} while (value);
_Py_write_noraise(fd, ptr, end - ptr);
}
/* Format an integer in range [0; 0xffffffff] to hexadecimal of 'width' digits,
and write it into the file fd.
This function is signal safe. */
void
_Py_DumpHexadecimal(int fd, unsigned long value, Py_ssize_t width)
{
char buffer[sizeof(unsigned long) * 2 + 1], *ptr, *end;
const Py_ssize_t size = Py_ARRAY_LENGTH(buffer) - 1;
if (width > size)
width = size;
/* it's ok if width is negative */
end = &buffer[size];
ptr = end;
*ptr = '\0';
do {
--ptr;
assert(ptr >= buffer);
*ptr = Py_hexdigits[value & 15];
value >>= 4;
} while ((end - ptr) < width || value);
_Py_write_noraise(fd, ptr, end - ptr);
}
void
_Py_DumpASCII(int fd, PyObject *text)
{
PyASCIIObject *ascii = (PyASCIIObject *)text;
Py_ssize_t i, size;
int truncated;
int kind;
void *data = NULL;
wchar_t *wstr = NULL;
Py_UCS4 ch;
if (!PyUnicode_Check(text))
return;
size = ascii->length;
kind = ascii->state.kind;
if (kind == PyUnicode_WCHAR_KIND) {
wstr = ((PyASCIIObject *)text)->wstr;
if (wstr == NULL)
return;
size = ((PyCompactUnicodeObject *)text)->wstr_length;
}
else if (ascii->state.compact) {
if (ascii->state.ascii)
data = ((PyASCIIObject*)text) + 1;
else
data = ((PyCompactUnicodeObject*)text) + 1;
}
else {
data = ((PyUnicodeObject *)text)->data.any;
if (data == NULL)
return;
}
if (MAX_STRING_LENGTH < size) {
size = MAX_STRING_LENGTH;
truncated = 1;
}
else {
truncated = 0;
}
for (i=0; i < size; i++) {
if (kind != PyUnicode_WCHAR_KIND)
ch = PyUnicode_READ(kind, data, i);
else
ch = wstr[i];
if (' ' f_lasti);
PUTS(fd, ", line ");
if (lineno >= 0) {
_Py_DumpDecimal(fd, (unsigned long)lineno);
}
else {
PUTS(fd, "???");
}
PUTS(fd, " in ");
if (code->co_name != NULL
&& PyUnicode_Check(code->co_name)) {
_Py_DumpASCII(fd, code->co_name);
}
else {
PUTS(fd, "???");
}
PUTS(fd, "\n");
Py_DECREF(code);
}
static void
dump_traceback(int fd, PyThreadState *tstate, int write_header)
{
PyFrameObject *frame;
unsigned int depth;
if (write_header) {
PUTS(fd, "Stack (most recent call first):\n");
}
frame = PyThreadState_GetFrame(tstate);
if (frame == NULL) {
PUTS(fd, "\n");
return;
}
depth = 0;
while (1) {
if (MAX_FRAME_DEPTH