Annotation of prex/usr/lib/posix/signal/__exception.c, Revision 1.1
1.1 ! nbrk 1: /*
! 2: * Copyright (c) 2005, Kohsuke Ohtani
! 3: * All rights reserved.
! 4: *
! 5: * Redistribution and use in source and binary forms, with or without
! 6: * modification, are permitted provided that the following conditions
! 7: * are met:
! 8: * 1. Redistributions of source code must retain the above copyright
! 9: * notice, this list of conditions and the following disclaimer.
! 10: * 2. Redistributions in binary form must reproduce the above copyright
! 11: * notice, this list of conditions and the following disclaimer in the
! 12: * documentation and/or other materials provided with the distribution.
! 13: * 3. Neither the name of the author nor the names of any co-contributors
! 14: * may be used to endorse or promote products derived from this software
! 15: * without specific prior written permission.
! 16: *
! 17: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
! 18: * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
! 19: * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
! 20: * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
! 21: * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
! 22: * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
! 23: * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
! 24: * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
! 25: * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
! 26: * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
! 27: * SUCH DAMAGE.
! 28: */
! 29:
! 30: #include <prex/prex.h>
! 31: #include <prex/signal.h>
! 32:
! 33: #include <unistd.h>
! 34: #include <signal.h>
! 35: #include <stdlib.h>
! 36:
! 37: void __exception_init(void);
! 38: void __exception_exit(void);
! 39:
! 40: struct sigaction __sig_act[NSIG];
! 41: sigset_t __sig_mask;
! 42: sigset_t __sig_pending;
! 43:
! 44: #ifdef _REENTRANT
! 45: volatile mutex_t __sig_lock;
! 46: #endif
! 47:
! 48: /*
! 49: * Process all pending and unmasked signal
! 50: *
! 51: * return 0 if at least one pending signal was processed.
! 52: * return -1 if no signal was processed.
! 53: */
! 54: int
! 55: __sig_flush(void)
! 56: {
! 57: int sig;
! 58: sigset_t active, org_mask;
! 59: struct sigaction action;
! 60: struct siginfo si;
! 61: int rc = -1;
! 62:
! 63: sig = 1;
! 64: for (;;) {
! 65: SIGNAL_LOCK();
! 66: active = __sig_pending & ~__sig_mask;
! 67: action = __sig_act[sig];
! 68: SIGNAL_UNLOCK();
! 69:
! 70: if (active == 0)
! 71: break;
! 72: if (active & sigmask(sig)) {
! 73:
! 74: SIGNAL_LOCK();
! 75: org_mask = __sig_mask;
! 76: __sig_mask |= action.sa_mask;
! 77: SIGNAL_UNLOCK();
! 78:
! 79: if (action.sa_handler == SIG_DFL) {
! 80: /* Default */
! 81: switch (sig) {
! 82: case SIGCHLD:
! 83: /* XXX: */
! 84: break;
! 85: default:
! 86: exit(0);
! 87: }
! 88: } else if (action.sa_handler != SIG_IGN) {
! 89: /* User defined */
! 90: if (action.sa_flags & SA_SIGINFO) {
! 91: si.si_signo = sig;
! 92: si.si_code = 0;
! 93: si.si_value.sival_int = 0;
! 94: action.sa_sigaction(sig, &si, NULL);
! 95: } else {
! 96: action.sa_handler(sig);
! 97: }
! 98: }
! 99: SIGNAL_LOCK();
! 100: __sig_pending &= ~sigmask(sig);
! 101: __sig_mask = org_mask;
! 102: SIGNAL_UNLOCK();
! 103:
! 104: switch (sig) {
! 105: case SIGILL:
! 106: case SIGTRAP:
! 107: case SIGFPE:
! 108: case SIGSEGV:
! 109: for (;;); /* exception from kernel */
! 110: break;
! 111: }
! 112: if (action.sa_handler != SIG_IGN)
! 113: rc = 0; /* Signal is processed */
! 114: }
! 115:
! 116: if (++sig >= NSIG)
! 117: sig = 1;
! 118: }
! 119: return rc;
! 120: }
! 121:
! 122: /*
! 123: * Exception handler for signal emulation
! 124: */
! 125: static void
! 126: __exception_handler(int excpt)
! 127: {
! 128:
! 129: if (excpt > 0 && excpt <= NSIG) {
! 130:
! 131: SIGNAL_LOCK();
! 132:
! 133: if (__sig_act[excpt].sa_handler != SIG_IGN)
! 134: __sig_pending |= sigmask(excpt);
! 135:
! 136: SIGNAL_UNLOCK();
! 137: }
! 138: __sig_flush();
! 139: exception_return();
! 140: }
! 141:
! 142: /*
! 143: * Initialize exception
! 144: */
! 145: void
! 146: __exception_init(void)
! 147: {
! 148: int i;
! 149:
! 150: #ifdef _REENTRANT
! 151: mutex_init(&__sig_lock);
! 152: #endif
! 153: exception_setup(NULL);
! 154:
! 155: __sig_mask = 0;
! 156: __sig_pending = 0;
! 157:
! 158: for (i = 0; i < NSIG; i++) {
! 159: __sig_act[i].sa_flags = 0;
! 160: __sig_act[i].sa_handler = SIG_DFL;
! 161: }
! 162:
! 163: /* Install exception handler */
! 164: exception_setup(__exception_handler);
! 165: }
! 166:
! 167: /*
! 168: * Clean up
! 169: */
! 170: void
! 171: __exception_exit(void)
! 172: {
! 173:
! 174: #ifdef _REENTRANT
! 175: mutex_destroy(&__sig_lock);
! 176: #endif
! 177: exception_setup(NULL);
! 178: }
CVSweb