| /* |
| --------------------------------------------------------------------- |
| / Copyright (c) 1996. \ |
| | The Regents of the University of California. | |
| | All rights reserved. | |
| | | |
| | Permission to use, copy, modify, and distribute this software for | |
| | any purpose without fee is hereby granted, provided that this en- | |
| | tire notice is included in all copies of any software which is or | |
| | includes a copy or modification of this software and in all | |
| | copies of the supporting documentation for such software. | |
| | | |
| | This work was produced at the University of California, Lawrence | |
| | Livermore National Laboratory under contract no. W-7405-ENG-48 | |
| | between the U.S. Department of Energy and The Regents of the | |
| | University of California for the operation of UC LLNL. | |
| | | |
| | DISCLAIMER | |
| | | |
| | This software was prepared as an account of work sponsored by an | |
| | agency of the United States Government. Neither the United States | |
| | Government nor the University of California nor any of their em- | |
| | ployees, makes any warranty, express or implied, or assumes any | |
| | liability or responsibility for the accuracy, completeness, or | |
| | usefulness of any information, apparatus, product, or process | |
| | disclosed, or represents that its use would not infringe | |
| | privately-owned rights. Reference herein to any specific commer- | |
| | cial products, process, or service by trade name, trademark, | |
| | manufacturer, or otherwise, does not necessarily constitute or | |
| | imply its endorsement, recommendation, or favoring by the United | |
| | States Government or the University of California. The views and | |
| | opinions of authors expressed herein do not necessarily state or | |
| | reflect those of the United States Government or the University | |
| | of California, and shall not be used for advertising or product | |
| \ endorsement purposes. / |
| --------------------------------------------------------------------- |
| */ |
| |
| /* |
| Floating point exception control module. |
| |
| This Python module provides bare-bones control over floating point |
| units from several hardware manufacturers. Specifically, it allows |
| the user to turn on the generation of SIGFPE whenever any of the |
| three serious IEEE 754 exceptions (Division by Zero, Overflow, |
| Invalid Operation) occurs. We currently ignore Underflow and |
| Inexact Result exceptions, although those could certainly be added |
| if desired. |
| |
| The module also establishes a signal handler for SIGFPE during |
| initialization. This builds on code found in the Python |
| distribution at Include/pyfpe.h and Python/pyfpe.c. If those files |
| are not in your Python distribution, find them in a patch at |
| ftp://icf.llnl.gov/pub/python/busby/patches.961108.tgz. |
| |
| This module is only useful to you if it happens to include code |
| specific for your hardware and software environment. If you can |
| contribute OS-specific code for new platforms, or corrections for |
| the code provided, it will be greatly appreciated. |
| |
| ** Version 1.0: September 20, 1996. Lee Busby, LLNL. |
| */ |
| |
| #ifdef __cplusplus |
| extern "C" { |
| #endif |
| |
| #include "Python.h" |
| #include <signal.h> |
| |
| #if defined(__FreeBSD__) |
| # include <ieeefp.h> |
| #endif |
| |
| #ifndef WANT_SIGFPE_HANDLER |
| /* Define locally if they are not defined in Python. This gives only |
| * the limited control to induce a core dump in case of an exception. |
| */ |
| #include <setjmp.h> |
| static jmp_buf PyFPE_jbuf; |
| static int PyFPE_counter = 0; |
| #endif |
| |
| typedef void Sigfunc(int); |
| static Sigfunc sigfpe_handler; |
| static void fpe_reset(Sigfunc *); |
| |
| static PyObject *fpe_error; |
| PyMODINIT_FUNC initfpectl(void); |
| static PyObject *turnon_sigfpe (PyObject *self,PyObject *args); |
| static PyObject *turnoff_sigfpe (PyObject *self,PyObject *args); |
| |
| static PyMethodDef fpectl_methods[] = { |
| {"turnon_sigfpe", (PyCFunction) turnon_sigfpe, METH_VARARGS}, |
| {"turnoff_sigfpe", (PyCFunction) turnoff_sigfpe, METH_VARARGS}, |
| {0,0} |
| }; |
| |
| static PyObject *turnon_sigfpe(PyObject *self,PyObject *args) |
| { |
| /* Do any architecture-specific one-time only initialization here. */ |
| |
| fpe_reset(sigfpe_handler); |
| Py_INCREF (Py_None); |
| return Py_None; |
| } |
| |
| static void fpe_reset(Sigfunc *handler) |
| { |
| /* Reset the exception handling machinery, and reset the signal |
| * handler for SIGFPE to the given handler. |
| */ |
| |
| /*-- IRIX -----------------------------------------------------------------*/ |
| #if defined(sgi) |
| /* See man page on handle_sigfpes -- must link with -lfpe |
| * My usage doesn't follow the man page exactly. Maybe somebody |
| * else can explain handle_sigfpes to me.... |
| * cc -c -I/usr/local/python/include fpectlmodule.c |
| * ld -shared -o fpectlmodule.so fpectlmodule.o -lfpe |
| */ |
| #include <sigfpe.h> |
| typedef void user_routine (unsigned[5], int[2]); |
| typedef void abort_routine (unsigned long); |
| handle_sigfpes(_OFF, 0, |
| (user_routine *)0, |
| _TURN_OFF_HANDLER_ON_ERROR, |
| NULL); |
| handle_sigfpes(_ON, _EN_OVERFL | _EN_DIVZERO | _EN_INVALID, |
| (user_routine *)0, |
| _ABORT_ON_ERROR, |
| NULL); |
| PyOS_setsig(SIGFPE, handler); |
| |
| /*-- SunOS and Solaris ----------------------------------------------------*/ |
| #elif defined(sun) |
| /* References: ieee_handler, ieee_sun, ieee_functions, and ieee_flags |
| man pages (SunOS or Solaris) |
| cc -c -I/usr/local/python/include fpectlmodule.c |
| ld -G -o fpectlmodule.so -L/opt/SUNWspro/lib fpectlmodule.o -lsunmath -lm |
| */ |
| #include <math.h> |
| #ifndef _SUNMATH_H |
| extern void nonstandard_arithmetic(void); |
| extern int ieee_flags(const char*, const char*, const char*, char **); |
| extern long ieee_handler(const char*, const char*, sigfpe_handler_type); |
| #endif |
| |
| char *mode="exception", *in="all", *out; |
| (void) nonstandard_arithmetic(); |
| (void) ieee_flags("clearall",mode,in,&out); |
| (void) ieee_handler("set","common",(sigfpe_handler_type)handler); |
| PyOS_setsig(SIGFPE, handler); |
| |
| /*-- HPUX -----------------------------------------------------------------*/ |
| #elif defined(__hppa) || defined(hppa) |
| /* References: fpsetmask man page */ |
| /* cc -Aa +z -c -I/usr/local/python/include fpectlmodule.c */ |
| /* ld -b -o fpectlmodule.sl fpectlmodule.o -lm */ |
| #include <math.h> |
| fpsetdefaults(); |
| PyOS_setsig(SIGFPE, handler); |
| |
| /*-- IBM AIX --------------------------------------------------------------*/ |
| #elif defined(__AIX) || defined(_AIX) |
| /* References: fp_trap, fp_enable man pages */ |
| #include <fptrap.h> |
| fp_trap(FP_TRAP_SYNC); |
| fp_enable(TRP_INVALID | TRP_DIV_BY_ZERO | TRP_OVERFLOW); |
| PyOS_setsig(SIGFPE, handler); |
| |
| /*-- DEC ALPHA OSF --------------------------------------------------------*/ |
| #elif defined(__alpha) && defined(__osf__) |
| /* References: exception_intro, ieee man pages */ |
| /* cc -c -I/usr/local/python/include fpectlmodule.c */ |
| /* ld -shared -o fpectlmodule.so fpectlmodule.o */ |
| #include <machine/fpu.h> |
| unsigned long fp_control = |
| IEEE_TRAP_ENABLE_INV | IEEE_TRAP_ENABLE_DZE | IEEE_TRAP_ENABLE_OVF; |
| ieee_set_fp_control(fp_control); |
| PyOS_setsig(SIGFPE, handler); |
| |
| /*-- DEC ALPHA LINUX ------------------------------------------------------*/ |
| #elif defined(__alpha) && defined(linux) |
| #include <asm/fpu.h> |
| unsigned long fp_control = |
| IEEE_TRAP_ENABLE_INV | IEEE_TRAP_ENABLE_DZE | IEEE_TRAP_ENABLE_OVF; |
| ieee_set_fp_control(fp_control); |
| PyOS_setsig(SIGFPE, handler); |
| |
| /*-- DEC ALPHA VMS --------------------------------------------------------*/ |
| #elif defined(__ALPHA) && defined(__VMS) |
| PyOS_setsig(SIGFPE, handler); |
| |
| /*-- Cray Unicos ----------------------------------------------------------*/ |
| #elif defined(cray) |
| /* UNICOS delivers SIGFPE by default, but no matherr */ |
| #ifdef HAS_LIBMSET |
| libmset(-1); |
| #endif |
| PyOS_setsig(SIGFPE, handler); |
| |
| /*-- FreeBSD ----------------------------------------------------------------*/ |
| #elif defined(__FreeBSD__) |
| fpresetsticky(fpgetsticky()); |
| fpsetmask(FP_X_INV | FP_X_DZ | FP_X_OFL); |
| PyOS_setsig(SIGFPE, handler); |
| |
| /*-- Linux ----------------------------------------------------------------*/ |
| #elif defined(linux) |
| #ifdef __GLIBC__ |
| #include <fpu_control.h> |
| #else |
| #include <i386/fpu_control.h> |
| #endif |
| #ifdef _FPU_SETCW |
| { |
| fpu_control_t cw = 0x1372; |
| _FPU_SETCW(cw); |
| } |
| #else |
| __setfpucw(0x1372); |
| #endif |
| PyOS_setsig(SIGFPE, handler); |
| |
| /*-- Microsoft Windows, NT ------------------------------------------------*/ |
| #elif defined(_MSC_VER) |
| /* Reference: Visual C++ Books Online 4.2, |
| Run-Time Library Reference, _control87, _controlfp */ |
| #include <float.h> |
| unsigned int cw = _EM_INVALID | _EM_ZERODIVIDE | _EM_OVERFLOW; |
| (void)_controlfp(0, cw); |
| PyOS_setsig(SIGFPE, handler); |
| |
| /*-- Give Up --------------------------------------------------------------*/ |
| #else |
| fputs("Operation not implemented\n", stderr); |
| #endif |
| |
| } |
| |
| static PyObject *turnoff_sigfpe(PyObject *self,PyObject *args) |
| { |
| #ifdef __FreeBSD__ |
| fpresetsticky(fpgetsticky()); |
| fpsetmask(0); |
| #else |
| fputs("Operation not implemented\n", stderr); |
| #endif |
| Py_INCREF(Py_None); |
| return Py_None; |
| } |
| |
| static void sigfpe_handler(int signo) |
| { |
| fpe_reset(sigfpe_handler); |
| if(PyFPE_counter) { |
| longjmp(PyFPE_jbuf, 1); |
| } else { |
| Py_FatalError("Unprotected floating point exception"); |
| } |
| } |
| |
| PyMODINIT_FUNC initfpectl(void) |
| { |
| PyObject *m, *d; |
| m = Py_InitModule("fpectl", fpectl_methods); |
| d = PyModule_GetDict(m); |
| fpe_error = PyErr_NewException("fpectl.error", NULL, NULL); |
| if (fpe_error != NULL) |
| PyDict_SetItemString(d, "error", fpe_error); |
| } |
| |
| #ifdef __cplusplus |
| } |
| #endif |