/* Error handling */

#include "Python.h"

#ifndef __STDC__

#ifndef MS_WINDOWS

extern char *strerror(int);

#endif

#endif

#ifdef MS_WINDOWS

#include <windows.h>

#include <winbase.h>

#endif

#include <ctype.h>

#ifdef __cplusplus

extern "C" {

#endif

void

PyErr_Restore(PyObject *type, PyObject *value, PyObject *traceback)

{

PyThreadState *tstate = PyThreadState_GET();

PyObject *oldtype, *oldvalue, *oldtraceback;

if (traceback != NULL && !PyTraceBack_Check(traceback)) {

/* XXX Should never happen -- fatal error instead? */

/* Well, it could be None. */

Py_DECREF(traceback);

traceback = NULL;

}

/* Save these in locals to safeguard against recursive

invocation through Py_XDECREF */

oldtype = tstate->curexc_type;

oldvalue = tstate->curexc_value;

oldtraceback = tstate->curexc_traceback;

tstate->curexc_type = type;

tstate->curexc_value = value;

tstate->curexc_traceback = traceback;

Py_XDECREF(oldtype);

Py_XDECREF(oldvalue);

Py_XDECREF(oldtraceback);

}

void

PyErr_SetObject(PyObject *exception, PyObject *value)

{

PyThreadState *tstate = PyThreadState_GET();

PyObject *exc_value;

PyObject *tb = NULL;

if (exception != NULL &&

!PyExceptionClass_Check(exception)) {

PyErr_Format(PyExc_SystemError,

"exception %R not a BaseException subclass",

exception);

return;

}

Py_XINCREF(value);

exc_value = tstate->exc_value;

if (exc_value != NULL && exc_value != Py_None) {

/* Implicit exception chaining */

Py_INCREF(exc_value);

if (value == NULL || !PyExceptionInstance_Check(value)) {

/* We must normalize the value right now */

PyObject *args, *fixed_value;

if (value == NULL || value == Py_None)

args = PyTuple_New(0);

else if (PyTuple_Check(value)) {

Py_INCREF(value);

args = value;

}

else

args = PyTuple_Pack(1, value);

fixed_value = args ?

PyEval_CallObject(exception, args) : NULL;

Py_XDECREF(args);

Py_XDECREF(value);

if (fixed_value == NULL)

return;

value = fixed_value;

}

/* Avoid reference cycles through the context chain.

This is O(chain length) but context chains are

usually very short. Sensitive readers may try

to inline the call to PyException_GetContext. */

if (exc_value != value) {

PyObject *o = exc_value, *context;

while ((context = PyException_GetContext(o))) {

Py_DECREF(context);

if (context == value) {

PyException_SetContext(o, NULL);

break;

}

o = context;

}

PyException_SetContext(value, exc_value);

} else {

Py_DECREF(exc_value);

}

}

if (value != NULL && PyExceptionInstance_Check(value))

tb = PyException_GetTraceback(value);

Py_XINCREF(exception);

PyErr_Restore(exception, value, tb);

}

void

PyErr_SetNone(PyObject *exception)

{

PyErr_SetObject(exception, (PyObject *)NULL);

}

void

PyErr_SetString(PyObject *exception, const char *string)

{

PyObject *value = PyUnicode_FromString(string);

PyErr_SetObject(exception, value);

Py_XDECREF(value);

}

PyObject *

PyErr_Occurred(void)

{

/* If there is no thread state, PyThreadState_GET calls

Py_FatalError, which calls PyErr_Occurred. To avoid the

resulting infinite loop, we inline PyThreadState_GET here and

treat no thread as no error. */

PyThreadState *tstate =

((PyThreadState*)_Py_atomic_load_relaxed(&_PyThreadState_Current));

return tstate == NULL ? NULL : tstate->curexc_type;

}

int

PyErr_GivenExceptionMatches(PyObject *err, PyObject *exc)

{

if (err == NULL || exc == NULL) {

/* maybe caused by "import exceptions" that failed early on */

return 0;

}

if (PyTuple_Check(exc)) {

Py_ssize_t i, n;

n = PyTuple_Size(exc);

for (i = 0; i < n; i++) {

/* Test recursively */

if (PyErr_GivenExceptionMatches(

err, PyTuple_GET_ITEM(exc, i)))

{

return 1;

}

}

return 0;

}

/* err might be an instance, so check its class. */

if (PyExceptionInstance_Check(err))

err = PyExceptionInstance_Class(err);

if (PyExceptionClass_Check(err) && PyExceptionClass_Check(exc)) {

int res = 0;

PyObject *exception, *value, *tb;

PyErr_Fetch(&exception, &value, &tb);

/* PyObject_IsSubclass() can recurse and therefore is

not safe (see test_bad_getattr in test.pickletester). */

res = PyType_IsSubtype((PyTypeObject *)err, (PyTypeObject *)exc);

/* This function must not fail, so print the error here */

if (res == -1) {

PyErr_WriteUnraisable(err);

res = 0;

}

PyErr_Restore(exception, value, tb);

return res;

}

return err == exc;

}

int

PyErr_ExceptionMatches(PyObject *exc)

{

return PyErr_GivenExceptionMatches(PyErr_Occurred(), exc);

}

/* Used in many places to normalize a raised exception, including in

eval_code2(), do_raise(), and PyErr_Print()

XXX: should PyErr_NormalizeException() also call

PyException_SetTraceback() with the resulting value and tb?

*/

void

PyErr_NormalizeException(PyObject **exc, PyObject **val, PyObject **tb)

{

PyObject *type = *exc;

PyObject *value = *val;

PyObject *inclass = NULL;

PyObject *initial_tb = NULL;

PyThreadState *tstate = NULL;

if (type == NULL) {

/* There was no exception, so nothing to do. */

return;

}

/* If PyErr_SetNone() was used, the value will have been actually

set to NULL.

*/

if (!value) {

value = Py_None;

Py_INCREF(value);

}

if (PyExceptionInstance_Check(value))

inclass = PyExceptionInstance_Class(value);

/* Normalize the exception so that if the type is a class, the

value will be an instance.

*/

if (PyExceptionClass_Check(type)) {

/* if the value was not an instance, or is not an instance

whose class is (or is derived from) type, then use the

value as an argument to instantiation of the type

class.

*/

if (!inclass || !PyObject_IsSubclass(inclass, type)) {

PyObject *args, *res;

if (value == Py_None)

args = PyTuple_New(0);

else if (PyTuple_Check(value)) {

Py_INCREF(value);

args = value;

}

else

args = PyTuple_Pack(1, value);

if (args == NULL)

goto finally;

res = PyEval_CallObject(type, args);

Py_DECREF(args);

if (res == NULL)

goto finally;

Py_DECREF(value);

value = res;

}

/* if the class of the instance doesn't exactly match the

class of the type, believe the instance

*/

else if (inclass != type) {

Py_DECREF(type);

type = inclass;

Py_INCREF(type);

}

}

*exc = type;

*val = value;

return;

finally:

Py_DECREF(type);

Py_DECREF(value);

/* If the new exception doesn't set a traceback and the old

exception had a traceback, use the old traceback for the

new exception. It's better than nothing.

*/

initial_tb = *tb;

PyErr_Fetch(exc, val, tb);

if (initial_tb != NULL) {

if (*tb == NULL)

*tb = initial_tb;

else

Py_DECREF(initial_tb);

}

/* normalize recursively */

tstate = PyThreadState_GET();

if (++tstate->recursion_depth > Py_GetRecursionLimit()) {

--tstate->recursion_depth;

/* throw away the old exception... */

Py_DECREF(*exc);

Py_DECREF(*val);

/* ... and use the recursion error instead */

*exc = PyExc_RuntimeError;

*val = PyExc_RecursionErrorInst;

Py_INCREF(*exc);

Py_INCREF(*val);

/* just keeping the old traceback */

return;

}

PyErr_NormalizeException(exc, val, tb);

--tstate->recursion_depth;

}

void

PyErr_Fetch(PyObject **p_type, PyObject **p_value, PyObject **p_traceback)

{

PyThreadState *tstate = PyThreadState_GET();

*p_type = tstate->curexc_type;

*p_value = tstate->curexc_value;

*p_traceback = tstate->curexc_traceback;

tstate->curexc_type = NULL;

tstate->curexc_value = NULL;

tstate->curexc_traceback = NULL;

}

void

PyErr_Clear(void)

{

PyErr_Restore(NULL, NULL, NULL);

}

/* Convenience functions to set a type error exception and return 0 */

int

PyErr_BadArgument(void)

{

PyErr_SetString(PyExc_TypeError,

"bad argument type for built-in operation");

return 0;

}

PyObject *

PyErr_NoMemory(void)

{

if (PyErr_ExceptionMatches(PyExc_MemoryError))

/* already current */

return NULL;

/* raise the pre-allocated instance if it still exists */

if (PyExc_MemoryErrorInst)

{

/* Clear the previous traceback, otherwise it will be appended

* to the current one.

*

* The following statement is not likely to raise any error;

* if it does, we simply discard it.

*/

PyException_SetTraceback(PyExc_MemoryErrorInst, Py_None);

PyErr_SetObject(PyExc_MemoryError, PyExc_MemoryErrorInst);

}

else

/* this will probably fail since there's no memory and hee,

hee, we have to instantiate this class

*/

PyErr_SetNone(PyExc_MemoryError);

return NULL;

}

PyObject *

PyErr_SetFromErrnoWithFilenameObject(PyObject *exc, PyObject *filenameObject)

{

PyObject *message;

PyObject *v;

int i = errno;

#ifndef MS_WINDOWS

char *s;

#else

WCHAR *s_buf = NULL;

#endif /* Unix/Windows */

#ifdef EINTR

if (i == EINTR && PyErr_CheckSignals())

return NULL;

#endif

#ifndef MS_WINDOWS

if (i == 0)

s = "Error"; /* Sometimes errno didn't get set */

else

s = strerror(i);

message = PyUnicode_DecodeUTF8(s, strlen(s), "ignore");

#else

if (i == 0)

message = PyUnicode_FromString("Error"); /* Sometimes errno didn't get set */

else

{

/* Note that the Win32 errors do not lineup with the

errno error. So if the error is in the MSVC error

table, we use it, otherwise we assume it really _is_

a Win32 error code

*/

if (i > 0 && i < _sys_nerr) {

message = PyUnicode_FromString(_sys_errlist[i]);

}

else {

int len = FormatMessageW(

FORMAT_MESSAGE_ALLOCATE_BUFFER |

FORMAT_MESSAGE_FROM_SYSTEM |

FORMAT_MESSAGE_IGNORE_INSERTS,

NULL, /* no message source */

i,

MAKELANGID(LANG_NEUTRAL,

SUBLANG_DEFAULT),

/* Default language */

(LPWSTR) &s_buf,

0, /* size not used */

NULL); /* no args */

if (len==0) {

/* Only ever seen this in out-of-mem

situations */

s_buf = NULL;

message = PyUnicode_FromFormat("Windows Error 0x%X", i);

} else {

/* remove trailing cr/lf and dots */

while (len > 0 && (s_buf[len-1] <= L' ' || s_buf[len-1] == L'.'))

s_buf[--len] = L'\0';

message = PyUnicode_FromUnicode(s_buf, len);

}

}

}

#endif /* Unix/Windows */

if (message == NULL)

{

#ifdef MS_WINDOWS

LocalFree(s_buf);

#endif

return NULL;

}

if (filenameObject != NULL)

v = Py_BuildValue("(iOO)", i, message, filenameObject);

else

v = Py_BuildValue("(iO)", i, message);

Py_DECREF(message);

if (v != NULL) {

PyErr_SetObject(exc, v);

Py_DECREF(v);

}

#ifdef MS_WINDOWS

LocalFree(s_buf);

#endif

return NULL;

}

PyObject *

PyErr_SetFromErrnoWithFilename(PyObject *exc, const char *filename)

{

PyObject *name = filename ? PyUnicode_DecodeFSDefault(filename) : NULL;

PyObject *result = PyErr_SetFromErrnoWithFilenameObject(exc, name);

Py_XDECREF(name);

return result;

}

#ifdef MS_WINDOWS

PyObject *

PyErr_SetFromErrnoWithUnicodeFilename(PyObject *exc, const Py_UNICODE *filename)

{

PyObject *name = filename ?

PyUnicode_FromUnicode(filename, wcslen(filename)) :

NULL;

PyObject *result = PyErr_SetFromErrnoWithFilenameObject(exc, name);

Py_XDECREF(name);

return result;

}

#endif /* MS_WINDOWS */

PyObject *

PyErr_SetFromErrno(PyObject *exc)

{

return PyErr_SetFromErrnoWithFilenameObject(exc, NULL);

}

#ifdef MS_WINDOWS

/* Windows specific error code handling */

PyObject *PyErr_SetExcFromWindowsErrWithFilenameObject(

PyObject *exc,

int ierr,

PyObject *filenameObject)

{

int len;

WCHAR *s_buf = NULL; /* Free via LocalFree */

PyObject *message;

PyObject *v;

DWORD err = (DWORD)ierr;

if (err==0) err = GetLastError();

len = FormatMessageW(

/* Error API error */

FORMAT_MESSAGE_ALLOCATE_BUFFER |

FORMAT_MESSAGE_FROM_SYSTEM |

FORMAT_MESSAGE_IGNORE_INSERTS,

NULL, /* no message source */

err,

MAKELANGID(LANG_NEUTRAL,

SUBLANG_DEFAULT), /* Default language */

(LPWSTR) &s_buf,

0, /* size not used */

NULL); /* no args */

if (len==0) {

/* Only seen this in out of mem situations */

message = PyUnicode_FromFormat("Windows Error 0x%X", err);

s_buf = NULL;

} else {

/* remove trailing cr/lf and dots */

while (len > 0 && (s_buf[len-1] <= L' ' || s_buf[len-1] == L'.'))

s_buf[--len] = L'\0';

message = PyUnicode_FromUnicode(s_buf, len);

}

if (message == NULL)

{

LocalFree(s_buf);

return NULL;

}

if (filenameObject != NULL)

v = Py_BuildValue("(iOO)", err, message, filenameObject);

else

v = Py_BuildValue("(iO)", err, message);

Py_DECREF(message);

if (v != NULL) {

PyErr_SetObject(exc, v);

Py_DECREF(v);

}

LocalFree(s_buf);

return NULL;

}

PyObject *PyErr_SetExcFromWindowsErrWithFilename(

PyObject *exc,

int ierr,

const char *filename)

{

PyObject *name = filename ? PyUnicode_FromString(filename) : NULL;

PyObject *ret = PyErr_SetExcFromWindowsErrWithFilenameObject(exc,

ierr,

name);

Py_XDECREF(name);

return ret;

}

PyObject *PyErr_SetExcFromWindowsErrWithUnicodeFilename(

PyObject *exc,

int ierr,

const Py_UNICODE *filename)

{

PyObject *name = filename ?

PyUnicode_FromUnicode(filename, wcslen(filename)) :

NULL;

PyObject *ret = PyErr_SetExcFromWindowsErrWithFilenameObject(exc,

ierr,

name);

Py_XDECREF(name);

return ret;

}

PyObject *PyErr_SetExcFromWindowsErr(PyObject *exc, int ierr)

{

return PyErr_SetExcFromWindowsErrWithFilename(exc, ierr, NULL);

}

PyObject *PyErr_SetFromWindowsErr(int ierr)

{

return PyErr_SetExcFromWindowsErrWithFilename(PyExc_WindowsError,

ierr, NULL);

}

PyObject *PyErr_SetFromWindowsErrWithFilename(

int ierr,

const char *filename)

{

PyObject *name = filename ? PyUnicode_FromString(filename) : NULL;

PyObject *result = PyErr_SetExcFromWindowsErrWithFilenameObject(

PyExc_WindowsError,

ierr, name);

Py_XDECREF(name);

return result;

}

PyObject *PyErr_SetFromWindowsErrWithUnicodeFilename(

int ierr,

const Py_UNICODE *filename)

{

PyObject *name = filename ?

PyUnicode_FromUnicode(filename, wcslen(filename)) :

NULL;

PyObject *result = PyErr_SetExcFromWindowsErrWithFilenameObject(

PyExc_WindowsError,

ierr, name);

Py_XDECREF(name);

return result;

}

#endif /* MS_WINDOWS */

void

_PyErr_BadInternalCall(const char *filename, int lineno)

{

PyErr_Format(PyExc_SystemError,

"%s:%d: bad argument to internal function",

filename, lineno);

}

/* Remove the preprocessor macro for PyErr_BadInternalCall() so that we can

export the entry point for existing object code: */

#undef PyErr_BadInternalCall

void

PyErr_BadInternalCall(void)

{

PyErr_Format(PyExc_SystemError,

"bad argument to internal function");

}

#define PyErr_BadInternalCall() _PyErr_BadInternalCall(__FILE__, __LINE__)

PyObject *

PyErr_Format(PyObject *exception, const char *format, ...)

{

va_list vargs;

PyObject* string;

#ifdef HAVE_STDARG_PROTOTYPES

va_start(vargs, format);

#else

va_start(vargs);

#endif

string = PyUnicode_FromFormatV(format, vargs);

PyErr_SetObject(exception, string);

Py_XDECREF(string);

va_end(vargs);

return NULL;

}

PyObject *

PyErr_NewException(const char *name, PyObject *base, PyObject *dict)

{

const char *dot;

PyObject *modulename = NULL;

PyObject *classname = NULL;

PyObject *mydict = NULL;

PyObject *bases = NULL;

PyObject *result = NULL;

dot = strrchr(name, '.');

if (dot == NULL) {

PyErr_SetString(PyExc_SystemError,

"PyErr_NewException: name must be module.class");

return NULL;

}

if (base == NULL)

base = PyExc_Exception;

if (dict == NULL) {

dict = mydict = PyDict_New();

if (dict == NULL)

goto failure;

}

if (PyDict_GetItemString(dict, "__module__") == NULL) {

modulename = PyUnicode_FromStringAndSize(name,

(Py_ssize_t)(dot-name));

if (modulename == NULL)

goto failure;

if (PyDict_SetItemString(dict, "__module__", modulename) != 0)

goto failure;

}

if (PyTuple_Check(base)) {

bases = base;

/* INCREF as we create a new ref in the else branch */

Py_INCREF(bases);

} else {

bases = PyTuple_Pack(1, base);

if (bases == NULL)

goto failure;

}

/* Create a real new-style class. */

result = PyObject_CallFunction((PyObject *)&PyType_Type, "sOO",

dot+1, bases, dict);

failure:

Py_XDECREF(bases);

Py_XDECREF(mydict);

Py_XDECREF(classname);

Py_XDECREF(modulename);

return result;

}

/* Create an exception with docstring */

PyObject *

PyErr_NewExceptionWithDoc(const char *name, const char *doc,

PyObject *base, PyObject *dict)

{

int result;

PyObject *ret = NULL;

PyObject *mydict = NULL; /* points to the dict only if we create it */

PyObject *docobj;

if (dict == NULL) {

dict = mydict = PyDict_New();

if (dict == NULL) {

return NULL;

}

}

if (doc != NULL) {

docobj = PyUnicode_FromString(doc);

if (docobj == NULL)

goto failure;

result = PyDict_SetItemString(dict, "__doc__", docobj);

Py_DECREF(docobj);

if (result < 0)

goto failure;

}

ret = PyErr_NewException(name, base, dict);

failure:

Py_XDECREF(mydict);

return ret;

}

/* Call when an exception has occurred but there is no way for Python

to handle it. Examples: exception in __del__ or during GC. */

void

PyErr_WriteUnraisable(PyObject *obj)

{

PyObject *f, *t, *v, *tb;

PyErr_Fetch(&t, &v, &tb);

f = PySys_GetObject("stderr");

if (f != NULL && f != Py_None) {

PyFile_WriteString("Exception ", f);

if (t) {

PyObject* moduleName;

char* className;

assert(PyExceptionClass_Check(t));

className = PyExceptionClass_Name(t);

if (className != NULL) {

char *dot = strrchr(className, '.');

if (dot != NULL)

className = dot+1;

}

moduleName = PyObject_GetAttrString(t, "__module__");

if (moduleName == NULL)

PyFile_WriteString("<unknown>", f);

else {

char* modstr = _PyUnicode_AsString(moduleName);

if (modstr &&

strcmp(modstr, "builtins") != 0)

{

PyFile_WriteString(modstr, f);

PyFile_WriteString(".", f);

}

}

if (className == NULL)

PyFile_WriteString("<unknown>", f);

else

PyFile_WriteString(className, f);

if (v && v != Py_None) {

PyFile_WriteString(": ", f);

PyFile_WriteObject(v, f, 0);

}

Py_XDECREF(moduleName);

}

PyFile_WriteString(" in ", f);

PyFile_WriteObject(obj, f, 0);

PyFile_WriteString(" ignored\n", f);

PyErr_Clear(); /* Just in case */

}

Py_XDECREF(t);

Py_XDECREF(v);

Py_XDECREF(tb);

}

extern PyObject *PyModule_GetWarningsModule(void);

void

PyErr_SyntaxLocation(const char *filename, int lineno) {

PyErr_SyntaxLocationEx(filename, lineno, -1);

}

/* Set file and line information for the current exception.

If the exception is not a SyntaxError, also sets additional attributes

to make printing of exceptions believe it is a syntax error. */

void

PyErr_SyntaxLocationEx(const char *filename, int lineno, int col_offset)

{

PyObject *exc, *v, *tb, *tmp;

/* add attributes for the line number and filename for the error */

PyErr_Fetch(&exc, &v, &tb);

PyErr_NormalizeException(&exc, &v, &tb);

/* XXX check that it is, indeed, a syntax error. It might not

* be, though. */

tmp = PyLong_FromLong(lineno);

if (tmp == NULL)

PyErr_Clear();

else {

if (PyObject_SetAttrString(v, "lineno", tmp))

PyErr_Clear();

Py_DECREF(tmp);

}

if (col_offset >= 0) {

tmp = PyLong_FromLong(col_offset);

if (tmp == NULL)

PyErr_Clear();

else {

if (PyObject_SetAttrString(v, "offset", tmp))

PyErr_Clear();

Py_DECREF(tmp);

}

}

if (filename != NULL) {

tmp = PyUnicode_FromString(filename);

if (tmp == NULL)

PyErr_Clear();

else {

if (PyObject_SetAttrString(v, "filename", tmp))

PyErr_Clear();

Py_DECREF(tmp);

}

tmp = PyErr_ProgramText(filename, lineno);

if (tmp) {

if (PyObject_SetAttrString(v, "text", tmp))

PyErr_Clear();

Py_DECREF(tmp);

}

}

if (PyObject_SetAttrString(v, "offset", Py_None)) {

PyErr_Clear();

}

if (exc != PyExc_SyntaxError) {

if (!PyObject_HasAttrString(v, "msg")) {

tmp = PyObject_Str(v);

if (tmp) {

if (PyObject_SetAttrString(v, "msg", tmp))

PyErr_Clear();

Py_DECREF(tmp);

} else {

PyErr_Clear();

}

}

if (!PyObject_HasAttrString(v, "print_file_and_line")) {

if (PyObject_SetAttrString(v, "print_file_and_line",

Py_None))

PyErr_Clear();

}

}

PyErr_Restore(exc, v, tb);

}

/* Attempt to load the line of text that the exception refers to. If it

fails, it will return NULL but will not set an exception.

XXX The functionality of this function is quite similar to the

functionality in tb_displayline() in traceback.c. */

PyObject *

PyErr_ProgramText(const char *filename, int lineno)

{

FILE *fp;

int i;

char linebuf[1000];

if (filename == NULL || *filename == '\0' || lineno <= 0)

return NULL;

fp = fopen(filename, "r" PY_STDIOTEXTMODE);

if (fp == NULL)

return NULL;

for (i = 0; i < lineno; i++) {

char *pLastChar = &linebuf[sizeof(linebuf) - 2];

do {

*pLastChar = '\0';

if (Py_UniversalNewlineFgets(linebuf, sizeof linebuf,

fp, 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');

}

fclose(fp);

if (i == lineno) {

char *p = linebuf;

PyObject *res;

while (*p == ' ' || *p == '\t' || *p == '\014')

p++;

res = PyUnicode_FromString(p);

if (res == NULL)

PyErr_Clear();

return res;

}

return NULL;

}

#ifdef __cplusplus

}

#endif