freebsd-skq/bin/sh/error.h
jilles 760264169e Fix various things about SIGINT handling:
* exception handlers are now run with interrupts disabled, which avoids
  many race conditions
* fix some cases where SIGINT only aborts one command and continues the
  script, in particular if a SIGINT causes an EINTR error which trumped the
  interrupt.

Example:
  sh -c 'echo < /some/fifo; echo This should not be printed'
The fifo should not have writers. When pressing ctrl+c to abort the open,
the shell used to continue with the next command.

Example:
  sh -c '/bin/echo < /some/fifo; echo This should not be printed'
Similar. Note, however, that this particular case did not and does not work
in interactive mode with job control enabled.
2009-11-22 18:23:30 +00:00

94 lines
3.5 KiB
C

/*-
* Copyright (c) 1991, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Kenneth Almquist.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)error.h 8.2 (Berkeley) 5/4/95
* $FreeBSD$
*/
/*
* We enclose jmp_buf in a structure so that we can declare pointers to
* jump locations. The global variable handler contains the location to
* jump to when an exception occurs, and the global variable exception
* contains a code identifying the exception. To implement nested
* exception handlers, the user should save the value of handler on entry
* to an inner scope, set handler to point to a jmploc structure for the
* inner scope, and restore handler on exit from the scope.
*/
#include <setjmp.h>
#include <signal.h>
struct jmploc {
jmp_buf loc;
};
extern struct jmploc *handler;
extern volatile sig_atomic_t exception;
/* exceptions */
#define EXINT 0 /* SIGINT received */
#define EXERROR 1 /* a generic error */
#define EXSHELLPROC 2 /* execute a shell procedure */
#define EXEXEC 3 /* command execution failed */
/*
* These macros allow the user to suspend the handling of interrupt signals
* over a period of time. This is similar to SIGHOLD to or sigblock, but
* much more efficient and portable. (But hacking the kernel is so much
* more fun than worrying about efficiency and portability. :-))
*/
extern volatile sig_atomic_t suppressint;
extern volatile sig_atomic_t intpending;
#define INTOFF suppressint++
#define INTON { if (--suppressint == 0 && intpending) onint(); }
#define is_int_on() suppressint
#define SETINTON(s) suppressint = (s)
#define FORCEINTON {suppressint = 0; if (intpending) onint();}
#define CLEAR_PENDING_INT intpending = 0
#define int_pending() intpending
void exraise(int);
void onint(void);
void error(const char *, ...) __printf0like(1, 2);
void exerror(int, const char *, ...) __printf0like(2, 3);
/*
* BSD setjmp saves the signal mask, which violates ANSI C and takes time,
* so we use _setjmp instead.
*/
#define setjmp(jmploc) _setjmp(jmploc)
#define longjmp(jmploc, val) _longjmp(jmploc, val)