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 58 struct jmploc *handler; 59 volatile sig_atomic_t exception; 60 volatile sig_atomic_t suppressint; 61 volatile sig_atomic_t intpending; 62 63 64 static 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 75 void 76 exraise(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 97 void 98 onint(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 } 121 122 123 static void 124 vwarning(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 } 133 134 135 void 136 warning(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 */ 150 static void 151 verrorwithstatus(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 } 177 178 179 void 180 error(const char *msg, ...) 181 { 182 va_list ap; 183 va_start(ap, msg); 184 verrorwithstatus(2, msg, ap); 185 va_end(ap); 186 } 187 188 189 void 190 errorwithstatus(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 } 197