/*********************************************************** Copyright (c) 2000, BeOpen.com. Copyright (c) 1995-2000, Corporation for National Research Initiatives. Copyright (c) 1990-1995, Stichting Mathematisch Centrum. All rights reserved. See the file "Misc/COPYRIGHT" for information on usage and redistribution of this file, and for a DISCLAIMER OF ALL WARRANTIES. ******************************************************************/ /* 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 (err == NULL || exc == NULL) { /* maybe caused by "import exceptions" that failed early on */ return 0; } 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) 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) 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; } id='n207' href='#n207'>207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421
/* Thread package.
This is intended to be usable independently from Python.
The implementation for system foobar is in a file thread_foobar.h
which is included by this file dependent on config settings.
Stuff shared by all thread_*.h files is collected here. */
#include "Python.h"
#ifndef _POSIX_THREADS
/* This means pthreads are not implemented in libc headers, hence the macro
not present in unistd.h. But they still can be implemented as an external
library (e.g. gnu pth in pthread emulation) */
# ifdef HAVE_PTHREAD_H
# include <pthread.h> /* _POSIX_THREADS */
# endif
#endif
#ifndef DONT_HAVE_STDIO_H
#include <stdio.h>
#endif
#include <stdlib.h>
#ifdef __sgi
#ifndef HAVE_PTHREAD_H /* XXX Need to check in configure.ac */
#undef _POSIX_THREADS
#endif
#endif
#include "pythread.h"
#ifndef _POSIX_THREADS
#ifdef __sgi
#define SGI_THREADS
#endif
#ifdef HAVE_THREAD_H
#define SOLARIS_THREADS
#endif
#if defined(sun) && !defined(SOLARIS_THREADS)
#define SUN_LWP
#endif
/* Check if we're running on HP-UX and _SC_THREADS is defined. If so, then
enough of the Posix threads package is implemented to support python
threads.
This is valid for HP-UX 11.23 running on an ia64 system. If needed, add
a check of __ia64 to verify that we're running on a ia64 system instead
of a pa-risc system.
*/
#ifdef __hpux
#ifdef _SC_THREADS
#define _POSIX_THREADS
#endif
#endif
#endif /* _POSIX_THREADS */
#ifdef Py_DEBUG
static int thread_debug = 0;
#define dprintf(args) (void)((thread_debug & 1) && printf args)
#define d2printf(args) ((thread_debug & 8) && printf args)
#else
#define dprintf(args)
#define d2printf(args)
#endif
static int initialized;
static void PyThread__init_thread(void); /* Forward */
void
PyThread_init_thread(void)
{
#ifdef Py_DEBUG
char *p = Py_GETENV("PYTHONTHREADDEBUG");
if (p) {
if (*p)
thread_debug = atoi(p);
else
thread_debug = 1;
}
#endif /* Py_DEBUG */
if (initialized)
return;
initialized = 1;
dprintf(("PyThread_init_thread called\n"));
PyThread__init_thread();
}
/* Support for runtime thread stack size tuning.
A value of 0 means using the platform's default stack size
or the size specified by the THREAD_STACK_SIZE macro. */
static size_t _pythread_stacksize = 0;
#ifdef SGI_THREADS
#include "thread_sgi.h"
#endif
#ifdef SOLARIS_THREADS
#include "thread_solaris.h"
#endif
#ifdef SUN_LWP
#include "thread_lwp.h"
#endif
#ifdef HAVE_PTH
#include "thread_pth.h"
#undef _POSIX_THREADS
#endif
#ifdef _POSIX_THREADS
#include "thread_pthread.h"
#endif
#ifdef C_THREADS
#include "thread_cthread.h"
#endif
#ifdef NT_THREADS
#include "thread_nt.h"
#endif
#ifdef OS2_THREADS
#include "thread_os2.h"
#endif
#ifdef BEOS_THREADS
#include "thread_beos.h"
#endif
#ifdef PLAN9_THREADS
#include "thread_plan9.h"
#endif
#ifdef ATHEOS_THREADS
#include "thread_atheos.h"
#endif
/*
#ifdef FOOBAR_THREADS
#include "thread_foobar.h"
#endif
*/
/* return the current thread stack size */
size_t
PyThread_get_stacksize(void)
{
return _pythread_stacksize;
}
/* Only platforms defining a THREAD_SET_STACKSIZE() macro
in thread_<platform>.h support changing the stack size.
Return 0 if stack size is valid,
-1 if stack size value is invalid,
-2 if setting stack size is not supported. */
int
PyThread_set_stacksize(size_t size)
{
#if defined(THREAD_SET_STACKSIZE)
return THREAD_SET_STACKSIZE(size);
#else
return -2;
#endif
}
#ifndef Py_HAVE_NATIVE_TLS
/* If the platform has not supplied a platform specific
TLS implementation, provide our own.
This code stolen from "thread_sgi.h", where it was the only
implementation of an existing Python TLS API.
*/
/* ------------------------------------------------------------------------
Per-thread data ("key") support.
Use PyThread_create_key() to create a new key. This is typically shared
across threads.
Use PyThread_set_key_value(thekey, value) to associate void* value with
thekey in the current thread. Each thread has a distinct mapping of thekey
to a void* value. Caution: if the current thread already has a mapping
for thekey, value is ignored.
Use PyThread_get_key_value(thekey) to retrieve the void* value associated
with thekey in the current thread. This returns NULL if no value is
associated with thekey in the current thread.
Use PyThread_delete_key_value(thekey) to forget the current thread's associated
value for thekey. PyThread_delete_key(thekey) forgets the values associated
with thekey across *all* threads.
While some of these functions have error-return values, none set any
Python exception.
None of the functions does memory management on behalf of the void* values.
You need to allocate and deallocate them yourself. If the void* values
happen to be PyObject*, these functions don't do refcount operations on
them either.
The GIL does not need to be held when calling these functions; they supply
their own locking. This isn't true of PyThread_create_key(), though (see
next paragraph).
There's a hidden assumption that PyThread_create_key() will be called before
any of the other functions are called. There's also a hidden assumption
that calls to PyThread_create_key() are serialized externally.
------------------------------------------------------------------------ */
/* A singly-linked list of struct key objects remembers all the key->value
* associations. File static keyhead heads the list. keymutex is used
* to enforce exclusion internally.
*/
struct key {
/* Next record in the list, or NULL if this is the last record. */
struct key *next;
/* The thread id, according to PyThread_get_thread_ident(). */
long id;
/* The key and its associated value. */
int key;
void *value;
};
static struct key *keyhead = NULL;
static PyThread_type_lock keymutex = NULL;
static int nkeys = 0; /* PyThread_create_key() hands out nkeys+1 next */
/* Internal helper.
* If the current thread has a mapping for key, the appropriate struct key*
* is returned. NB: value is ignored in this case!
* If there is no mapping for key in the current thread, then:
* If value is NULL, NULL is returned.
* Else a mapping of key to value is created for the current thread,
* and a pointer to a new struct key* is returned; except that if
* malloc() can't find room for a new struct key*, NULL is returned.
* So when value==NULL, this acts like a pure lookup routine, and when
* value!=NULL, this acts like dict.setdefault(), returning an existing
* mapping if one exists, else creating a new mapping.
*
* Caution: this used to be too clever, trying to hold keymutex only
* around the "p->next = keyhead; keyhead = p" pair. That allowed
* another thread to mutate the list, via key deletion, concurrent with
* find_key() crawling over the list. Hilarity ensued. For example, when
* the for-loop here does "p = p->next", p could end up pointing at a
* record that PyThread_delete_key_value() was concurrently free()'ing.
* That could lead to anything, from failing to find a key that exists, to
* segfaults. Now we lock the whole routine.
*/
static struct key *
find_key(int key, void *value)
{
struct key *p, *prev_p;
long id = PyThread_get_thread_ident();
if (!keymutex)
return NULL;
PyThread_acquire_lock(keymutex, 1);
prev_p = NULL;
for (p = keyhead; p != NULL; p = p->next) {
if (p->id == id && p->key == key)
goto Done;
/* Sanity check. These states should never happen but if
* they do we must abort. Otherwise we'll end up spinning in
* in a tight loop with the lock held. A similar check is done
* in pystate.c tstate_delete_common(). */
if (p == prev_p)
Py_FatalError("tls find_key: small circular list(!)");
prev_p = p;
if (p->next == keyhead)
Py_FatalError("tls find_key: circular list(!)");
}
if (value == NULL) {
assert(p == NULL);
goto Done;
}
p = (struct key *)malloc(sizeof(struct key));
if (p != NULL) {
p->id = id;
p->key = key;
p->value = value;
p->next = keyhead;
keyhead = p;
}
Done:
PyThread_release_lock(keymutex);
return p;
}
/* Return a new key. This must be called before any other functions in
* this family, and callers must arrange to serialize calls to this
* function. No violations are detected.
*/
int
PyThread_create_key(void)
{
/* All parts of this function are wrong if it's called by multiple
* threads simultaneously.
*/
if (keymutex == NULL)
keymutex = PyThread_allocate_lock();
return ++nkeys;
}
/* Forget the associations for key across *all* threads. */
void
PyThread_delete_key(int key)
{
struct key *p, **q;
PyThread_acquire_lock(keymutex, 1);
q = &keyhead;
while ((p = *q) != NULL) {
if (p->key == key) {
*q = p->next;
free((void *)p);
/* NB This does *not* free p->value! */
}
else
q = &p->next;
}
PyThread_release_lock(keymutex);
}
/* Confusing: If the current thread has an association for key,
* value is ignored, and 0 is returned. Else an attempt is made to create
* an association of key to value for the current thread. 0 is returned
* if that succeeds, but -1 is returned if there's not enough memory
* to create the association. value must not be NULL.
*/
int
PyThread_set_key_value(int key, void *value)
{
struct key *p;
assert(value != NULL);
p = find_key(key, value);
if (p == NULL)
return -1;
else
return 0;
}
/* Retrieve the value associated with key in the current thread, or NULL
* if the current thread doesn't have an association for key.
*/
void *
PyThread_get_key_value(int key)
{
struct key *p = find_key(key, NULL);
if (p == NULL)
return NULL;
else
return p->value;
}
/* Forget the current thread's association for key, if any. */
void
PyThread_delete_key_value(int key)
{
long id = PyThread_get_thread_ident();
struct key *p, **q;
PyThread_acquire_lock(keymutex, 1);
q = &keyhead;
while ((p = *q) != NULL) {
if (p->key == key && p->id == id) {
*q = p->next;
free((void *)p);
/* NB This does *not* free p->value! */
break;
}
else
q = &p->next;
}
PyThread_release_lock(keymutex);
}
/* Forget everything not associated with the current thread id.
* This function is called from PyOS_AfterFork(). It is necessary
* because other thread ids which were in use at the time of the fork
* may be reused for new threads created in the forked process.
*/
void
PyThread_ReInitTLS(void)
{
long id = PyThread_get_thread_ident();
struct key *p, **q;
if (!keymutex)
return;
/* As with interpreter_lock in PyEval_ReInitThreads()
we just create a new lock without freeing the old one */
keymutex = PyThread_allocate_lock();
/* Delete all keys which do not match the current thread id */
q = &keyhead;
while ((p = *q) != NULL) {
if (p->id != id) {
*q = p->next;
free((void *)p);
/* NB This does *not* free p->value! */
}
else
q = &p->next;
}
}
#endif /* Py_HAVE_NATIVE_TLS */