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 33 #ifndef lint 34 #if 0 35 static char sccsid[] = "@(#)error.c 8.2 (Berkeley) 5/4/95"; 36 #endif 37 #endif /* not lint */ 38 #include <sys/cdefs.h> 39 __FBSDID("$FreeBSD$"); 40 41 /* 42 * Errors and exceptions. 43 */ 44 45 #include "shell.h" 46 #include "main.h" 47 #include "options.h" 48 #include "output.h" 49 #include "error.h" 50 #include "nodes.h" /* show.h needs nodes.h */ 51 #include "show.h" 52 #include "trap.h" 53 #include <signal.h> 54 #include <stdlib.h> 55 #include <unistd.h> 56 #include <errno.h> 57 58 59 /* 60 * Code to handle exceptions in C. 61 */ 62 63 struct jmploc *handler; 64 volatile sig_atomic_t exception; 65 volatile sig_atomic_t suppressint; 66 volatile sig_atomic_t intpending; 67 char *commandname; 68 69 70 static void exverror(int, const char *, va_list) __printf0like(2, 0) __dead2; 71 72 /* 73 * Called to raise an exception. Since C doesn't include exceptions, we 74 * just do a longjmp to the exception handler. The type of exception is 75 * stored in the global variable "exception". 76 * 77 * Interrupts are disabled; they should be reenabled when the exception is 78 * caught. 79 */ 80 81 void 82 exraise(int e) 83 { 84 INTOFF; 85 if (handler == NULL) 86 abort(); 87 exception = e; 88 longjmp(handler->loc, 1); 89 } 90 91 92 /* 93 * Called from trap.c when a SIGINT is received. (If the user specifies 94 * that SIGINT is to be trapped or ignored using the trap builtin, then 95 * this routine is not called.) Suppressint is nonzero when interrupts 96 * are held using the INTOFF macro. If SIGINTs are not suppressed and 97 * the shell is not a root shell, then we want to be terminated if we 98 * get here, as if we were terminated directly by a SIGINT. Arrange for 99 * this here. 100 */ 101 102 void 103 onint(void) 104 { 105 sigset_t sigs; 106 107 /* 108 * The !in_dotrap here is safe. The only way we can arrive here 109 * with in_dotrap set is that a trap handler set SIGINT to SIG_DFL 110 * and killed itself. 111 */ 112 113 if (suppressint && !in_dotrap) { 114 intpending++; 115 return; 116 } 117 intpending = 0; 118 sigemptyset(&sigs); 119 sigprocmask(SIG_SETMASK, &sigs, NULL); 120 121 /* 122 * This doesn't seem to be needed, since main() emits a newline. 123 */ 124 #if 0 125 if (tcgetpgrp(0) == getpid()) 126 write(STDERR_FILENO, "\n", 1); 127 #endif 128 if (rootshell && iflag) 129 exraise(EXINT); 130 else { 131 signal(SIGINT, SIG_DFL); 132 kill(getpid(), SIGINT); 133 } 134 } 135 136 137 /* 138 * Exverror is called to raise the error exception. If the first argument 139 * is not NULL then error prints an error message using printf style 140 * formatting. It then raises the error exception. 141 */ 142 static void 143 exverror(int cond, const char *msg, va_list ap) 144 { 145 /* 146 * An interrupt trumps an error. Certain places catch error 147 * exceptions or transform them to a plain nonzero exit code 148 * in child processes, and if an error exception can be handled, 149 * an interrupt can be handled as well. 150 * 151 * exraise() will disable interrupts for the exception handler. 152 */ 153 FORCEINTON; 154 155 #ifdef DEBUG 156 if (msg) 157 TRACE(("exverror(%d, \"%s\") pid=%d\n", cond, msg, getpid())); 158 else 159 TRACE(("exverror(%d, NULL) pid=%d\n", cond, getpid())); 160 #endif 161 if (msg) { 162 if (commandname) 163 outfmt(out2, "%s: ", commandname); 164 doformat(out2, msg, ap); 165 out2c('\n'); 166 } 167 flushall(); 168 exraise(cond); 169 } 170 171 172 void 173 error(const char *msg, ...) 174 { 175 va_list ap; 176 va_start(ap, msg); 177 exverror(EXERROR, msg, ap); 178 va_end(ap); 179 } 180 181 182 void 183 exerror(int cond, const char *msg, ...) 184 { 185 va_list ap; 186 va_start(ap, msg); 187 exverror(cond, msg, ap); 188 va_end(ap); 189 } 190