1 /* 2 * Copyright (c) 2009 Eric Faurot <eric@openbsd.org> 3 * 4 * Permission to use, copy, modify, and distribute this software for any 5 * purpose with or without fee is hereby granted, provided that the above 6 * copyright notice and this permission notice appear in all copies. 7 * 8 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 9 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 10 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 11 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 12 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 13 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 14 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 15 */ 16 17 #include <sys/param.h> 18 #include <sys/queue.h> 19 #include <sys/socket.h> 20 #include <sys/uio.h> 21 22 #include <errno.h> 23 #include <stdio.h> 24 #include <stdlib.h> 25 #include <string.h> 26 #include <unistd.h> 27 28 #include "imsgev.h" 29 30 void imsgev_add(struct imsgev *); 31 void imsgev_dispatch(int, short, void *); 32 void imsgev_disconnect(struct imsgev *, int); 33 34 void 35 imsgev_init(struct imsgev *iev, int fd, void *data, 36 void (*callback)(struct imsgev *, int, struct imsg *)) 37 { 38 imsg_init(&iev->ibuf, fd); 39 iev->terminate = 0; 40 41 iev->data = data; 42 iev->handler = imsgev_dispatch; 43 iev->callback = callback; 44 45 iev->events = EV_READ; 46 event_set(&iev->ev, iev->ibuf.fd, iev->events, iev->handler, iev); 47 event_add(&iev->ev, NULL); 48 } 49 50 int 51 imsgev_compose(struct imsgev *iev, u_int16_t type, u_int32_t peerid, 52 uint32_t pid, int fd, void *data, u_int16_t datalen) 53 { 54 int r; 55 56 r = imsg_compose(&iev->ibuf, type, peerid, pid, fd, data, datalen); 57 if (r != -1) 58 imsgev_add(iev); 59 60 return (r); 61 } 62 63 void 64 imsgev_close(struct imsgev *iev) 65 { 66 iev->terminate = 1; 67 imsgev_add(iev); 68 } 69 70 void 71 imsgev_clear(struct imsgev *iev) 72 { 73 event_del(&iev->ev); 74 msgbuf_clear(&iev->ibuf.w); 75 close(iev->ibuf.fd); 76 } 77 78 void 79 imsgev_add(struct imsgev *iev) 80 { 81 short events = 0; 82 83 if (!iev->terminate) 84 events = EV_READ; 85 if (iev->ibuf.w.queued || iev->terminate) 86 events |= EV_WRITE; 87 88 /* optimization: skip event_{del/set/add} if already set */ 89 if (events == iev->events) 90 return; 91 92 iev->events = events; 93 event_del(&iev->ev); 94 event_set(&iev->ev, iev->ibuf.fd, iev->events, iev->handler, iev); 95 event_add(&iev->ev, NULL); 96 } 97 98 void 99 imsgev_dispatch(int fd, short ev, void *humppa) 100 { 101 struct imsgev *iev = humppa; 102 struct imsgbuf *ibuf = &iev->ibuf; 103 struct imsg imsg; 104 ssize_t n; 105 106 iev->events = 0; 107 108 if (ev & EV_READ) { 109 if ((n = imsg_read(ibuf)) == -1) { 110 imsgev_disconnect(iev, IMSGEV_EREAD); 111 return; 112 } 113 if (n == 0) { 114 /* 115 * Connection is closed for reading, and we assume 116 * it is also closed for writing, so we error out 117 * if write data is pending. 118 */ 119 imsgev_disconnect(iev, 120 (iev->ibuf.w.queued) ? IMSGEV_EWRITE : IMSGEV_DONE); 121 return; 122 } 123 } 124 125 if (ev & EV_WRITE) { 126 /* 127 * We wanted to write data out but the connection is either 128 * closed, or some error occured. Both case are not recoverable 129 * from the imsg perspective, so we treat it as a WRITE error. 130 */ 131 if ((n = msgbuf_write(&ibuf->w)) != 0) { 132 imsgev_disconnect(iev, IMSGEV_EWRITE); 133 return; 134 } 135 } 136 137 while (iev->terminate == 0) { 138 if ((n = imsg_get(ibuf, &imsg)) == -1) { 139 imsgev_disconnect(iev, IMSGEV_EIMSG); 140 return; 141 } 142 if (n == 0) 143 break; 144 iev->callback(iev, IMSGEV_IMSG, &imsg); 145 imsg_free(&imsg); 146 } 147 148 if (iev->terminate && iev->ibuf.w.queued == 0) { 149 imsgev_disconnect(iev, IMSGEV_DONE); 150 return; 151 } 152 153 imsgev_add(iev); 154 } 155 156 void 157 imsgev_disconnect(struct imsgev *iev, int code) 158 { 159 iev->callback(iev, code, NULL); 160 } 161