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 * We enclose jmp_buf in a structure so that we can declare pointers to 37 * jump locations. The global variable handler contains the location to 38 * jump to when an exception occurs, and the global variable exception 39 * contains a code identifying the exception. To implement nested 40 * exception handlers, the user should save the value of handler on entry 41 * to an inner scope, set handler to point to a jmploc structure for the 42 * inner scope, and restore handler on exit from the scope. 43 */ 44 45 #include <setjmp.h> 46 #include <signal.h> 47 48 struct jmploc { 49 jmp_buf loc; 50 }; 51 52 extern struct jmploc *handler; 53 extern volatile sig_atomic_t exception; 54 55 /* exceptions */ 56 #define EXINT 0 /* SIGINT received */ 57 #define EXERROR 1 /* a generic error with exitstatus */ 58 #define EXEXIT 2 /* call exitshell(exitstatus) */ 59 60 61 /* 62 * These macros allow the user to suspend the handling of interrupt signals 63 * over a period of time. This is similar to SIGHOLD to or sigblock, but 64 * much more efficient and portable. (But hacking the kernel is so much 65 * more fun than worrying about efficiency and portability. :-)) 66 */ 67 68 extern volatile sig_atomic_t suppressint; 69 extern volatile sig_atomic_t intpending; 70 71 #define INTOFF suppressint++ 72 #define INTON { if (--suppressint == 0 && intpending) onint(); } 73 #define is_int_on() suppressint 74 #define SETINTON(s) do { suppressint = (s); if (suppressint == 0 && intpending) onint(); } while (0) 75 #define FORCEINTON {suppressint = 0; if (intpending) onint();} 76 #define SET_PENDING_INT intpending = 1 77 #define CLEAR_PENDING_INT intpending = 0 78 #define int_pending() intpending 79 80 void exraise(int) __dead2; 81 void onint(void) __dead2; 82 void warning(const char *, ...) __printflike(1, 2); 83 void error(const char *, ...) __printf0like(1, 2) __dead2; 84 void errorwithstatus(int, const char *, ...) __printf0like(2, 3) __dead2; 85 86 87 /* 88 * BSD setjmp saves the signal mask, which violates ANSI C and takes time, 89 * so we use _setjmp instead. 90 */ 91 92 #define setjmp(jmploc) _setjmp(jmploc) 93 #define longjmp(jmploc, val) _longjmp(jmploc, val) 94