1 /* 2 * Copyright (c) 2001, 2005, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26 #include "jni.h" 27 #include "jni_util.h" 28 #include "jvm.h" 29 #include "jlong.h" 30 #include "sun_nio_ch_PollArrayWrapper.h" 31 #include <poll.h> 32 #include <unistd.h> 33 #include <sys/time.h> 34 35 #define RESTARTABLE(_cmd, _result) do { \ 36 do { \ 37 _result = _cmd; \ 38 } while((_result == -1) && (errno == EINTR)); \ 39 } while(0) 40 41 static int 42 ipoll(struct pollfd fds[], unsigned int nfds, int timeout) 43 { 44 jlong start, now; 45 int remaining = timeout; 46 struct timeval t; 47 int diff; 48 49 gettimeofday(&t, NULL); 50 start = t.tv_sec * 1000 + t.tv_usec / 1000; 51 52 for (;;) { 53 int res = poll(fds, nfds, remaining); 54 if (res < 0 && errno == EINTR) { 55 if (remaining >= 0) { 56 gettimeofday(&t, NULL); 57 now = t.tv_sec * 1000 + t.tv_usec / 1000; 58 diff = now - start; 59 remaining -= diff; 60 if (diff < 0 || remaining <= 0) { 61 return 0; 62 } 63 start = now; 64 } 65 } else { 66 return res; 67 } 68 } 69 } 70 71 JNIEXPORT jint JNICALL 72 Java_sun_nio_ch_PollArrayWrapper_poll0(JNIEnv *env, jobject this, 73 jlong address, jint numfds, 74 jlong timeout) 75 { 76 struct pollfd *a; 77 int err = 0; 78 79 a = (struct pollfd *) jlong_to_ptr(address); 80 81 if (timeout <= 0) { /* Indefinite or no wait */ 82 RESTARTABLE (poll(a, numfds, timeout), err); 83 } else { /* Bounded wait; bounded restarts */ 84 err = ipoll(a, numfds, timeout); 85 } 86 87 if (err < 0) { 88 JNU_ThrowIOExceptionWithLastError(env, "Poll failed"); 89 } 90 return (jint)err; 91 } 92 93 JNIEXPORT void JNICALL 94 Java_sun_nio_ch_PollArrayWrapper_interrupt(JNIEnv *env, jobject this, jint fd) 95 { 96 int fakebuf[1]; 97 fakebuf[0] = 1; 98 if (write(fd, fakebuf, 1) < 0) { 99 JNU_ThrowIOExceptionWithLastError(env, 100 "Write to interrupt fd failed"); 101 } 102 }