error.h revision 104132
1/*-
2 * Copyright (c) 1991, 1993
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 * This code is derived from software contributed to Berkeley by
6 * Kenneth Almquist.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 * 3. All advertising materials mentioning features or use of this software
17 *    must display the following acknowledgement:
18 *	This product includes software developed by the University of
19 *	California, Berkeley and its contributors.
20 * 4. Neither the name of the University nor the names of its contributors
21 *    may be used to endorse or promote products derived from this software
22 *    without specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * SUCH DAMAGE.
35 *
36 *	@(#)error.h	8.2 (Berkeley) 5/4/95
37 * $FreeBSD: head/bin/sh/error.h 104132 2002-09-29 11:37:39Z tjr $
38 */
39
40/*
41 * We enclose jmp_buf in a structure so that we can declare pointers to
42 * jump locations.  The global variable handler contains the location to
43 * jump to when an exception occurs, and the global variable exception
44 * contains a code identifying the exception.  To implement nested
45 * exception handlers, the user should save the value of handler on entry
46 * to an inner scope, set handler to point to a jmploc structure for the
47 * inner scope, and restore handler on exit from the scope.
48 */
49
50#include <setjmp.h>
51#include <signal.h>
52
53struct jmploc {
54	jmp_buf loc;
55};
56
57extern struct jmploc *handler;
58extern volatile sig_atomic_t exception;
59
60/* exceptions */
61#define EXINT 0		/* SIGINT received */
62#define EXERROR 1	/* a generic error */
63#define EXSHELLPROC 2	/* execute a shell procedure */
64#define EXEXEC 3	/* command execution failed */
65
66
67/*
68 * These macros allow the user to suspend the handling of interrupt signals
69 * over a period of time.  This is similar to SIGHOLD to or sigblock, but
70 * much more efficient and portable.  (But hacking the kernel is so much
71 * more fun than worrying about efficiency and portability. :-))
72 */
73
74extern volatile sig_atomic_t suppressint;
75extern volatile sig_atomic_t intpending;
76
77#define INTOFF suppressint++
78#define INTON { if (--suppressint == 0 && intpending) onint(); }
79#define FORCEINTON {suppressint = 0; if (intpending) onint();}
80#define CLEAR_PENDING_INT intpending = 0
81#define int_pending() intpending
82
83void exraise(int);
84void onint(void);
85void error(const char *, ...) __printf0like(1, 2);
86void exerror(int, const char *, ...) __printf0like(2, 3);
87
88
89/*
90 * BSD setjmp saves the signal mask, which violates ANSI C and takes time,
91 * so we use _setjmp instead.
92 */
93
94#define setjmp(jmploc)	_setjmp(jmploc)
95#define longjmp(jmploc, val)	_longjmp(jmploc, val)
96