2 * Copyright (C) 2008 Intel Corporation
4 * mdmon socket / message handling
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms and conditions of the GNU General Public License,
8 * version 2, as published by the Free Software Foundation.
10 * This program is distributed in the hope it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
15 * You should have received a copy of the GNU General Public License along with
16 * this program; if not, write to the Free Software Foundation, Inc.,
17 * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
28 #include <sys/types.h>
29 #include <sys/socket.h>
34 static const __u32 start_magic = 0x5a5aa5a5;
35 static const __u32 end_magic = 0xa5a55a5a;
37 static int send_buf(int fd, const void* buf, int len, int tmo)
41 struct timeval timeout = {tmo, 0};
42 struct timeval *ptmo = tmo ? &timeout : NULL;
47 rv = select(fd+1, NULL, &set, NULL, ptmo);
50 rv = write(fd, buf, len);
59 static int recv_buf(int fd, void* buf, int len, int tmo)
63 struct timeval timeout = {tmo, 0};
64 struct timeval *ptmo = tmo ? &timeout : NULL;
69 rv = select(fd+1, &set, NULL, NULL, ptmo);
72 rv = read(fd, buf, len);
82 int send_message(int fd, struct metadata_update *msg, int tmo)
87 rv = send_buf(fd, &start_magic, 4, tmo);
88 rv = rv ?: send_buf(fd, &len, 4, tmo);
90 rv = rv ?: send_buf(fd, msg->buf, msg->len, tmo);
91 rv = send_buf(fd, &end_magic, 4, tmo);
96 int receive_message(int fd, struct metadata_update *msg, int tmo)
102 rv = recv_buf(fd, &magic, 4, tmo);
103 if (rv < 0 || magic != start_magic)
105 rv = recv_buf(fd, &len, 4, tmo);
106 if (rv < 0 || len > MSG_MAX_LEN)
109 msg->buf = malloc(len);
110 if (msg->buf == NULL)
112 rv = recv_buf(fd, msg->buf, len, tmo);
119 rv = recv_buf(fd, &magic, 4, tmo);
120 if (rv < 0 || magic != end_magic) {
128 int ack(int fd, int tmo)
130 struct metadata_update msg = { .len = 0 };
132 return send_message(fd, &msg, tmo);
135 int wait_reply(int fd, int tmo)
137 struct metadata_update msg;
138 return receive_message(fd, &msg, tmo);
141 int connect_monitor(char *devname)
146 struct sockaddr_un addr;
148 sprintf(path, "/var/run/mdadm/%s.sock", devname);
149 sfd = socket(PF_LOCAL, SOCK_STREAM, 0);
153 addr.sun_family = PF_LOCAL;
154 strcpy(addr.sun_path, path);
155 if (connect(sfd, &addr, sizeof(addr)) < 0) {
160 fl = fcntl(sfd, F_GETFL, 0);
162 fcntl(sfd, F_SETFL, fl);
167 int ping_monitor(char *devname)
169 int sfd = connect_monitor(devname);
175 /* try to ping existing socket */
176 if (ack(sfd, 20) != 0)
179 /* check the reply */
180 if (!err && wait_reply(sfd, 20) != 0)