cpython/Python/errors.c

485 lines
11 KiB
C

/***********************************************************
Copyright 1991-1995 by Stichting Mathematisch Centrum, Amsterdam,
The Netherlands.
All Rights Reserved
Permission to use, copy, modify, and distribute this software and its
documentation for any purpose and without fee is hereby granted,
provided that the above copyright notice appear in all copies and that
both that copyright notice and this permission notice appear in
supporting documentation, and that the names of Stichting Mathematisch
Centrum or CWI or Corporation for National Research Initiatives or
CNRI not be used in advertising or publicity pertaining to
distribution of the software without specific, written prior
permission.
While CWI is the initial source for this software, a modified version
is made available by the Corporation for National Research Initiatives
(CNRI) at the Internet address ftp://ftp.python.org.
STICHTING MATHEMATISCH CENTRUM AND CNRI DISCLAIM ALL WARRANTIES WITH
REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL STICHTING MATHEMATISCH
CENTRUM OR CNRI BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL
DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
PERFORMANCE OF THIS SOFTWARE.
******************************************************************/
/* Error handling */
#include "Python.h"
#ifdef SYMANTEC__CFM68K__
#pragma lib_export on
#endif
#ifdef macintosh
extern char *PyMac_StrError Py_PROTO((int));
#undef strerror
#define strerror PyMac_StrError
#endif /* macintosh */
#ifndef __STDC__
#ifndef MS_WINDOWS
extern char *strerror Py_PROTO((int));
#endif
#endif
#ifdef MS_WIN32
#include "windows.h"
#include "winbase.h"
#endif
void
PyErr_Restore(type, value, traceback)
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? */
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(exception, value)
PyObject *exception;
PyObject *value;
{
Py_XINCREF(exception);
Py_XINCREF(value);
PyErr_Restore(exception, value, (PyObject *)NULL);
}
void
PyErr_SetNone(exception)
PyObject *exception;
{
PyErr_SetObject(exception, (PyObject *)NULL);
}
void
PyErr_SetString(exception, string)
PyObject *exception;
const char *string;
{
PyObject *value = PyString_FromString(string);
PyErr_SetObject(exception, value);
Py_XDECREF(value);
}
PyObject *
PyErr_Occurred()
{
PyThreadState *tstate = PyThreadState_Get();
return tstate->curexc_type;
}
int
PyErr_GivenExceptionMatches(err, exc)
PyObject *err, *exc;
{
if (PyTuple_Check(exc)) {
int 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 (PyInstance_Check(err))
err = (PyObject*)((PyInstanceObject*)err)->in_class;
if (PyClass_Check(err) && PyClass_Check(exc))
return PyClass_IsSubclass(err, exc);
return err == exc;
}
int
PyErr_ExceptionMatches(exc)
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()
*/
void
PyErr_NormalizeException(exc, val, tb)
PyObject **exc;
PyObject **val;
PyObject **tb;
{
PyObject *type = *exc;
PyObject *value = *val;
PyObject *inclass = NULL;
/* If PyErr_SetNone() was used, the value will have been actually
set to NULL.
*/
if (!value) {
value = Py_None;
Py_INCREF(value);
}
if (PyInstance_Check(value))
inclass = (PyObject*)((PyInstanceObject*)value)->in_class;
/* Normalize the exception so that if the type is a class, the
value will be an instance.
*/
if (PyClass_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 || !PyClass_IsSubclass(inclass, type)) {
PyObject *args, *res;
if (value == Py_None)
args = Py_BuildValue("()");
else if (PyTuple_Check(value)) {
Py_INCREF(value);
args = value;
}
else
args = Py_BuildValue("(O)", 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);
Py_XDECREF(*tb);
PyErr_Fetch(exc, val, tb);
/* normalize recursively */
PyErr_NormalizeException(exc, val, tb);
}
void
PyErr_Fetch(p_type, p_value, p_traceback)
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()
{
PyErr_Restore(NULL, NULL, NULL);
}
/* Convenience functions to set a type error exception and return 0 */
int
PyErr_BadArgument()
{
PyErr_SetString(PyExc_TypeError,
"illegal argument type for built-in operation");
return 0;
}
PyObject *
PyErr_NoMemory()
{
/* raise the pre-allocated instance if it still exists */
if (PyExc_MemoryErrorInst)
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_SetFromErrnoWithFilename(exc, filename)
PyObject *exc;
char *filename;
{
PyObject *v;
char *s;
int i = errno;
#ifdef MS_WIN32
char *s_buf = NULL;
#endif
#ifdef EINTR
if (i == EINTR && PyErr_CheckSignals())
return NULL;
#endif
if (i == 0)
s = "Error"; /* Sometimes errno didn't get set */
else
#ifndef MS_WIN32
s = strerror(i);
#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) {
s = _sys_errlist[i];
}
else {
int len = FormatMessage(
FORMAT_MESSAGE_ALLOCATE_BUFFER |
FORMAT_MESSAGE_FROM_SYSTEM |
FORMAT_MESSAGE_IGNORE_INSERTS,
NULL, /* no message source */
i,
MAKELANGID(LANG_NEUTRAL,
SUBLANG_DEFAULT),
/* Default language */
(LPTSTR) &s_buf,
0, /* size not used */
NULL); /* no args */
s = s_buf;
/* remove trailing cr/lf and dots */
while (len > 0 && (s[len-1] <= ' ' || s[len-1] == '.'))
s[--len] = '\0';
}
}
#endif
if (filename != NULL && Py_UseClassExceptionsFlag)
v = Py_BuildValue("(iss)", i, s, filename);
else
v = Py_BuildValue("(is)", i, s);
if (v != NULL) {
PyErr_SetObject(exc, v);
Py_DECREF(v);
}
#ifdef MS_WIN32
LocalFree(s_buf);
#endif
return NULL;
}
PyObject *
PyErr_SetFromErrno(exc)
PyObject *exc;
{
return PyErr_SetFromErrnoWithFilename(exc, NULL);
}
#ifdef MS_WINDOWS
/* Windows specific error code handling */
PyObject *PyErr_SetFromWindowsErrWithFilename(
int ierr,
const char *filename)
{
int len;
char *s;
PyObject *v;
DWORD err = (DWORD)ierr;
if (err==0) err = GetLastError();
len = FormatMessage(
/* 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 */
(LPTSTR) &s,
0, /* size not used */
NULL); /* no args */
/* remove trailing cr/lf and dots */
while (len > 0 && (s[len-1] <= ' ' || s[len-1] == '.'))
s[--len] = '\0';
if (filename != NULL && Py_UseClassExceptionsFlag)
v = Py_BuildValue("(iss)", err, s, filename);
else
v = Py_BuildValue("(is)", err, s);
if (v != NULL) {
PyErr_SetObject(PyExc_WindowsError, v);
Py_DECREF(v);
}
LocalFree(s);
return NULL;
}
PyObject *PyErr_SetFromWindowsErr(int ierr)
{
return PyErr_SetFromWindowsErrWithFilename(ierr, NULL);
}
#endif /* MS_WINDOWS */
void
PyErr_BadInternalCall()
{
PyErr_SetString(PyExc_SystemError,
"bad argument to internal function");
}
#ifdef HAVE_STDARG_PROTOTYPES
PyObject *
PyErr_Format(PyObject *exception, const char *format, ...)
#else
PyObject *
PyErr_Format(exception, format, va_alist)
PyObject *exception;
const char *format;
va_dcl
#endif
{
va_list vargs;
char buffer[500]; /* Caller is responsible for limiting the format */
#ifdef HAVE_STDARG_PROTOTYPES
va_start(vargs, format);
#else
va_start(vargs);
#endif
vsprintf(buffer, format, vargs);
PyErr_SetString(exception, buffer);
return NULL;
}
PyObject *
PyErr_NewException(name, base, dict)
char *name; /* modulename.classname */
PyObject *base;
PyObject *dict;
{
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 (!PyClass_Check(base)) {
/* Must be using string-based standard exceptions (-X) */
return PyString_FromString(name);
}
if (dict == NULL) {
dict = mydict = PyDict_New();
if (dict == NULL)
goto failure;
}
if (PyDict_GetItemString(dict, "__module__") == NULL) {
modulename = PyString_FromStringAndSize(name, (int)(dot-name));
if (modulename == NULL)
goto failure;
if (PyDict_SetItemString(dict, "__module__", modulename) != 0)
goto failure;
}
classname = PyString_FromString(dot+1);
if (classname == NULL)
goto failure;
bases = Py_BuildValue("(O)", base);
if (bases == NULL)
goto failure;
result = PyClass_New(bases, dict, classname);
failure:
Py_XDECREF(bases);
Py_XDECREF(mydict);
Py_XDECREF(classname);
Py_XDECREF(modulename);
return result;
}