xref: /freebsd/bin/sh/error.h (revision 6195fb4102afbdfc3da8c0ac2e4cacb0f37d89a9)
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  * 4. Neither the name of the University nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  *
32  *	@(#)error.h	8.2 (Berkeley) 5/4/95
33  * $FreeBSD$
34  */
35 
36 /*
37  * We enclose jmp_buf in a structure so that we can declare pointers to
38  * jump locations.  The global variable handler contains the location to
39  * jump to when an exception occurs, and the global variable exception
40  * contains a code identifying the exception.  To implement nested
41  * exception handlers, the user should save the value of handler on entry
42  * to an inner scope, set handler to point to a jmploc structure for the
43  * inner scope, and restore handler on exit from the scope.
44  */
45 
46 #include <setjmp.h>
47 #include <signal.h>
48 
49 struct jmploc {
50 	jmp_buf loc;
51 };
52 
53 extern struct jmploc *handler;
54 extern volatile sig_atomic_t exception;
55 
56 /* exceptions */
57 #define EXINT 0		/* SIGINT received */
58 #define EXERROR 1	/* a generic error */
59 #define EXSHELLPROC 2	/* execute a shell procedure */
60 #define EXEXEC 3	/* command execution failed */
61 
62 
63 /*
64  * These macros allow the user to suspend the handling of interrupt signals
65  * over a period of time.  This is similar to SIGHOLD to or sigblock, but
66  * much more efficient and portable.  (But hacking the kernel is so much
67  * more fun than worrying about efficiency and portability. :-))
68  */
69 
70 extern volatile sig_atomic_t suppressint;
71 extern volatile sig_atomic_t intpending;
72 
73 #define INTOFF suppressint++
74 #define INTON { if (--suppressint == 0 && intpending) onint(); }
75 #define FORCEINTON {suppressint = 0; if (intpending) onint();}
76 #define CLEAR_PENDING_INT intpending = 0
77 #define int_pending() intpending
78 
79 void exraise(int);
80 void onint(void);
81 void error(const char *, ...) __printf0like(1, 2);
82 void exerror(int, const char *, ...) __printf0like(2, 3);
83 
84 
85 /*
86  * BSD setjmp saves the signal mask, which violates ANSI C and takes time,
87  * so we use _setjmp instead.
88  */
89 
90 #define setjmp(jmploc)	_setjmp(jmploc)
91 #define longjmp(jmploc, val)	_longjmp(jmploc, val)
92