xref: /freebsd/sbin/hastd/event.c (revision 193d9e768ba63fcfb187cfd17f461f7d41345048)
1 /*-
2  * Copyright (c) 2010 Pawel Jakub Dawidek <pjd@FreeBSD.org>
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  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include <errno.h>
31 
32 #include "hast.h"
33 #include "hast_proto.h"
34 #include "hooks.h"
35 #include "nv.h"
36 #include "pjdlog.h"
37 #include "proto.h"
38 #include "subr.h"
39 
40 #include "event.h"
41 
42 void
43 event_send(const struct hast_resource *res, int event)
44 {
45 	struct nv *nvin, *nvout;
46 	int error;
47 
48 	PJDLOG_ASSERT(res != NULL);
49 	PJDLOG_ASSERT(event >= EVENT_MIN && event <= EVENT_MAX);
50 
51 	nvin = nvout = NULL;
52 
53 	/*
54 	 * Prepare and send event to parent process.
55 	 */
56 	nvout = nv_alloc();
57 	nv_add_uint8(nvout, (uint8_t)event, "event");
58 	error = nv_error(nvout);
59 	if (error != 0) {
60 		pjdlog_common(LOG_ERR, 0, error,
61 		    "Unable to prepare event header");
62 		goto done;
63 	}
64 	if (hast_proto_send(res, res->hr_event, nvout, NULL, 0) == -1) {
65 		pjdlog_errno(LOG_ERR, "Unable to send event header");
66 		goto done;
67 	}
68 	if (hast_proto_recv_hdr(res->hr_event, &nvin) == -1) {
69 		pjdlog_errno(LOG_ERR, "Unable to receive event header");
70 		goto done;
71 	}
72 	/*
73 	 * Do nothing with the answer. We only wait for it to be sure not
74 	 * to exit too quickly after sending an event and exiting immediately.
75 	 */
76 done:
77 	if (nvin != NULL)
78 		nv_free(nvin);
79 	if (nvout != NULL)
80 		nv_free(nvout);
81 }
82 
83 int
84 event_recv(const struct hast_resource *res)
85 {
86 	struct nv *nvin, *nvout;
87 	const char *evstr;
88 	uint8_t event;
89 	int error;
90 
91 	PJDLOG_ASSERT(res != NULL);
92 
93 	nvin = nvout = NULL;
94 
95 	if (hast_proto_recv_hdr(res->hr_event, &nvin) == -1) {
96 		/*
97 		 * First error log as debug. This is because worker process
98 		 * most likely exited.
99 		 */
100 		pjdlog_common(LOG_DEBUG, 1, errno,
101 		    "Unable to receive event header");
102 		goto fail;
103 	}
104 
105 	event = nv_get_uint8(nvin, "event");
106 	if (event == EVENT_NONE) {
107 		pjdlog_error("Event header is missing 'event' field.");
108 		goto fail;
109 	}
110 
111 	switch (event) {
112 	case EVENT_CONNECT:
113 		evstr = "connect";
114 		break;
115 	case EVENT_DISCONNECT:
116 		evstr = "disconnect";
117 		break;
118 	case EVENT_SYNCSTART:
119 		evstr = "syncstart";
120 		break;
121 	case EVENT_SYNCDONE:
122 		evstr = "syncdone";
123 		break;
124 	case EVENT_SYNCINTR:
125 		evstr = "syncintr";
126 		break;
127 	case EVENT_SPLITBRAIN:
128 		evstr = "split-brain";
129 		break;
130 	default:
131 		pjdlog_error("Event header contain invalid event number (%hhu).",
132 		    event);
133 		goto fail;
134 	}
135 
136 	pjdlog_prefix_set("[%s] (%s) ", res->hr_name, role2str(res->hr_role));
137 	hook_exec(res->hr_exec, evstr, res->hr_name, NULL);
138 	pjdlog_prefix_set("%s", "");
139 
140 	nvout = nv_alloc();
141 	nv_add_int16(nvout, 0, "error");
142 	error = nv_error(nvout);
143 	if (error != 0) {
144 		pjdlog_common(LOG_ERR, 0, error,
145 		    "Unable to prepare event header");
146 		goto fail;
147 	}
148 	if (hast_proto_send(res, res->hr_event, nvout, NULL, 0) == -1) {
149 		pjdlog_errno(LOG_ERR, "Unable to send event header");
150 		goto fail;
151 	}
152 	nv_free(nvin);
153 	nv_free(nvout);
154 	return (0);
155 fail:
156 	if (nvin != NULL)
157 		nv_free(nvin);
158 	if (nvout != NULL)
159 		nv_free(nvout);
160 	return (-1);
161 }
162