error.h

/*-
 * 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.
 * 3. 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.
 */

/*
 * 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 with exitstatus */
#define EXEXIT 2	/* call exitshell(exitstatus) */


/*
 * 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) do { suppressint = (s); if (suppressint == 0 && intpending) onint(); } while (0)
#define FORCEINTON {suppressint = 0; if (intpending) onint();}
#define SET_PENDING_INT intpending = 1
#define CLEAR_PENDING_INT intpending = 0
#define int_pending() intpending

void exraise(int) __dead2;
void onint(void) __dead2;
void warning(const char *, ...) __printflike(1, 2);
void error(const char *, ...) __printf0like(1, 2) __dead2;
void errorwithstatus(int, const char *, ...) __printf0like(2, 3) __dead2;


/*
 * 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)