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Diffstat (limited to 'hurd/hurd/sigpreempt.h')
| -rw-r--r-- | hurd/hurd/sigpreempt.h | 90 |
1 files changed, 90 insertions, 0 deletions
diff --git a/hurd/hurd/sigpreempt.h b/hurd/hurd/sigpreempt.h new file mode 100644 index 0000000000..eed67b2e94 --- /dev/null +++ b/hurd/hurd/sigpreempt.h @@ -0,0 +1,90 @@ +/* Preemption of Hurd signals before POSIX.1 semantics take over. +Copyright (C) 1996 Free Software Foundation, Inc. +This file is part of the GNU C Library. + +The GNU C Library is free software; you can redistribute it and/or +modify it under the terms of the GNU Library General Public License as +published by the Free Software Foundation; either version 2 of the +License, or (at your option) any later version. + +The GNU C Library is distributed in the hope that it will be useful, +but WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +Library General Public License for more details. + +You should have received a copy of the GNU Library General Public +License along with the GNU C Library; see the file COPYING.LIB. If +not, write to the Free Software Foundation, Inc., 675 Mass Ave, +Cambridge, MA 02139, USA. */ + +#ifndef _HURD_SIGPREEMPT_H + +#define _HURD_SIGPREEMPT_H 1 +#include <errno.h> +#include <signal.h> /* For sigset_t, sighandler_t, SIG_ERR. */ +struct hurd_sigstate; /* <hurd/signal.h> */ + +struct hurd_signal_preempter + { + /* These members select which signals this structure will apply to. + The rest of the structure is only consulted if these match. */ + sigset_t signals; /* Signals preempted. */ + unsigned long int first, last; /* Range of sigcode values preempted. */ + + /* This function will be called (with SS->lock held) to decide what to + do with the signal described. It may modify the codes of the signal + passed. If the return value is SIG_ERR, the next matching preempter + is tried, or the normal handling is done for the signal (which may + have been changed by the preempter function). Otherwise, the signal + is processed as if the return value were its handler setting. */ + sighandler_t (*preempter) (struct hurd_signal_preempter *preempter, + struct hurd_sigstate *ss, + int *signo, long int *sigcode, int *sigerror); + /* If PREEMPTER is null, act as if it returned HANDLER. */ + sighandler_t handler; + + struct hurd_signal_preempter *next; /* List structure. */ + }; + +#define HURD_PREEMPT_SIGNAL_P(preempter, signo, sigcode) \ + (((preempter)->signals & sigmask (signo)) && \ + (sigcode) >= (preempter)->first && (sigcode) <= (preempter)->last) + + +/* Signal preempters applying to all threads; locked by _hurd_siglock. */ +extern struct hurd_signal_preempter *_hurdsig_preempters; +extern sigset_t _hurdsig_preempted_set; + + +/* The caller must initialize all members of *PREEMPTER except `next'. + The preempter is registered on the global list. */ +void hurd_preempt_signals (struct hurd_signal_preempter *preempter); + +/* Remove a preempter registered with hurd_preempt_signals. */ +void hurd_unpreempt_signals (struct hurd_signal_preempter *preempter); + + +/* Call *OPERATE and return its value. If a signal in SIGSET with a sigcode + in the range [FIRST,LAST] arrives during the call, catch it. If HANDLER + is a function, it handles the signal in the normal way (i.e. it should + longjmp unless it can restart the insn on return). If it is SIG_ERR, + hurd_catch_signal returns the sc_error value from the signal (or + EGRATUITOUS if that is zero). + + The preempter structure is passed to *OPERATE, which may modify its + sigcode range or functions at any time during which it is guaranteed no + signal in SIGSET will arrive. */ + +error_t hurd_catch_signal (sigset_t sigset, + unsigned long int first, unsigned long int last, + error_t (*operate) (struct hurd_signal_preempter *), + sighandler_t handler); + + +/* Convenience functions using `hurd_catch_signal'. */ + +error_t hurd_safe_memmove (void *dest, const void *src, size_t nbytes); +error_t hurd_safe_memset (void *dest, int byte, size_t nbytes); + + +#endif /* hurd/sigpreempt.h */ |