1/*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1991, 1993
5 * The Regents of the University of California. All rights reserved.
6 *
7 * This code is derived from software contributed to Berkeley by
8 * Kenneth Almquist.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. Neither the name of the University nor the names of its contributors
19 * may be used to endorse or promote products derived from this software
20 * without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 */
34
35/*
36 * Errors and exceptions.
37 */
38
39#include "shell.h"
40#include "eval.h"
41#include "main.h"
42#include "options.h"
43#include "output.h"
44#include "error.h"
45#include "nodes.h" /* show.h needs nodes.h */
46#include "show.h"
47#include "trap.h"
48#include <signal.h>
49#include <stdlib.h>
50#include <unistd.h>
51#include <errno.h>
52
53
54/*
55 * Code to handle exceptions in C.
56 */
57
58struct jmploc *handler;
59volatile sig_atomic_t exception;
60volatile sig_atomic_t suppressint;
61volatile sig_atomic_t intpending;
62
63
64static void verrorwithstatus(int, const char *, va_list) __printf0like(2, 0) __dead2;
65
66/*
67 * Called to raise an exception. Since C doesn't include exceptions, we
68 * just do a longjmp to the exception handler. The type of exception is
69 * stored in the global variable "exception".
70 *
71 * Interrupts are disabled; they should be re-enabled when the exception is
72 * caught.
73 */
74
75void
76exraise(int e)
77{
78 INTOFF;
79 if (handler == NULL)
80 abort();
81 exception = e;
82 longjmp(handler->loc, 1);
83}
84
85
86/*
87 * Called from trap.c when a SIGINT is received and not suppressed, or when
88 * an interrupt is pending and interrupts are re-enabled using INTON.
89 * (If the user specifies that SIGINT is to be trapped or ignored using the
90 * trap builtin, then this routine is not called.) Suppressint is nonzero
91 * when interrupts are held using the INTOFF macro. If SIGINTs are not
92 * suppressed and the shell is not a root shell, then we want to be
93 * terminated if we get here, as if we were terminated directly by a SIGINT.
94 * Arrange for this here.
95 */
96
97void
98onint(void)
99{
100 sigset_t sigs;
101
102 intpending = 0;
103 sigemptyset(&sigs);
104 sigprocmask(SIG_SETMASK, &sigs, NULL);
105
106 /*
107 * This doesn't seem to be needed, since main() emits a newline.
108 */
109#if 0
110 if (tcgetpgrp(0) == getpid())
111 write(STDERR_FILENO, "\n", 1);
112#endif
113 if (rootshell && iflag)
114 exraise(EXINT);
115 else {
116 signal(SIGINT, SIG_DFL);
117 kill(getpid(), SIGINT);
118 _exit(128 + SIGINT);
119 }
120}
121
122
123static void
124vwarning(const char *msg, va_list ap)
125{
126 if (commandname)
127 outfmt(out2, "%s: ", commandname);
128 else if (arg0)
129 outfmt(out2, "%s: ", arg0);
130 doformat(out2, msg, ap);
131 out2fmt_flush("\n");
132}
133
134
135void
136warning(const char *msg, ...)
137{
138 va_list ap;
139 va_start(ap, msg);
140 vwarning(msg, ap);
141 va_end(ap);
142}
143
144
145/*
146 * Exverror is called to raise the error exception. If the first argument
147 * is not NULL then error prints an error message using printf style
148 * formatting. It then raises the error exception.
149 */
150static void
151verrorwithstatus(int status, const char *msg, va_list ap)
152{
153 /*
154 * An interrupt trumps an error. Certain places catch error
155 * exceptions or transform them to a plain nonzero exit code
156 * in child processes, and if an error exception can be handled,
157 * an interrupt can be handled as well.
158 *
159 * exraise() will disable interrupts for the exception handler.
160 */
161 FORCEINTON;
162
163#ifdef DEBUG
164 if (msg)
165 TRACE(("verrorwithstatus(%d, \"%s\") pid=%d\n",
166 status, msg, getpid()));
167 else
168 TRACE(("verrorwithstatus(%d, NULL) pid=%d\n",
169 status, getpid()));
170#endif
171 if (msg)
172 vwarning(msg, ap);
173 flushall();
174 exitstatus = status;
175 exraise(EXERROR);
176}
177
178
179void
180error(const char *msg, ...)
181{
182 va_list ap;
183 va_start(ap, msg);
184 verrorwithstatus(2, msg, ap);
185 va_end(ap);
186}
187
188
189void
190errorwithstatus(int status, const char *msg, ...)
191{
192 va_list ap;
193 va_start(ap, msg);
194 verrorwithstatus(status, msg, ap);
195 va_end(ap);
196}
