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 * 3. 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 /* 34 * We enclose jmp_buf in a structure so that we can declare pointers to 35 * jump locations. The global variable handler contains the location to 36 * jump to when an exception occurs, and the global variable exception 37 * contains a code identifying the exception. To implement nested 38 * exception handlers, the user should save the value of handler on entry 39 * to an inner scope, set handler to point to a jmploc structure for the 40 * inner scope, and restore handler on exit from the scope. 41 */ 42 43 #include <setjmp.h> 44 #include <signal.h> 45 46 struct jmploc { 47 jmp_buf loc; 48 }; 49 50 extern struct jmploc *handler; 51 extern volatile sig_atomic_t exception; 52 53 /* exceptions */ 54 #define EXINT 0 /* SIGINT received */ 55 #define EXERROR 1 /* a generic error with exitstatus */ 56 #define EXEXIT 2 /* call exitshell(exitstatus) */ 57 58 59 /* 60 * These macros allow the user to suspend the handling of interrupt signals 61 * over a period of time. This is similar to SIGHOLD to or sigblock, but 62 * much more efficient and portable. (But hacking the kernel is so much 63 * more fun than worrying about efficiency and portability. :-)) 64 */ 65 66 extern volatile sig_atomic_t suppressint; 67 extern volatile sig_atomic_t intpending; 68 69 #define INTOFF suppressint++ 70 #define INTON { if (--suppressint == 0 && intpending) onint(); } 71 #define is_int_on() suppressint 72 #define SETINTON(s) do { suppressint = (s); if (suppressint == 0 && intpending) onint(); } while (0) 73 #define FORCEINTON {suppressint = 0; if (intpending) onint();} 74 #define SET_PENDING_INT intpending = 1 75 #define CLEAR_PENDING_INT intpending = 0 76 #define int_pending() intpending 77 78 void exraise(int) __dead2; 79 void onint(void) __dead2; 80 void warning(const char *, ...) __printflike(1, 2); 81 void error(const char *, ...) __printf0like(1, 2) __dead2; 82 void errorwithstatus(int, const char *, ...) __printf0like(2, 3) __dead2; 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