git.ozlabs.org Git - petitboot/blob - discover/discover-server.c

   1
   2 #include <unistd.h>
   3 #include <stdlib.h>
   4 #include <stdio.h>
   5 #include <stdint.h>
   6 #include <errno.h>
   7 #include <assert.h>
   8
   9 #include <sys/socket.h>
  10 #include <sys/un.h>
  11 #include <asm/byteorder.h>
  12
  13 #include <talloc/talloc.h>
  14 #include <waiter/waiter.h>
  15 #include <log/log.h>
  16
  17 #include "pb-protocol/pb-protocol.h"
  18 #include "list/list.h"
  19
  20 #include "device-handler.h"
  21 #include "discover-server.h"
  22
  23 struct discover_server {
  24         int socket;
  25         struct waitset *waitset;
  26         struct waiter *waiter;
  27         struct list clients;
  28         struct device_handler *device_handler;
  29 };
  30
  31 struct client {
  32         struct discover_server *server;
  33         struct list_item list;
  34         int fd;
  35 };
  36
  37
  38 static int server_destructor(void *arg)
  39 {
  40         struct discover_server *server = arg;
  41
  42         if (server->waiter)
  43                 waiter_remove(server->waiter);
  44
  45         if (server->socket >= 0)
  46                 close(server->socket);
  47
  48         return 0;
  49 }
  50
  51 static int client_destructor(void *arg)
  52 {
  53         struct client *client = arg;
  54
  55         if (client->fd >= 0)
  56                 close(client->fd);
  57
  58         list_remove(&client->list);
  59
  60         return 0;
  61
  62 }
  63
  64 static void print_clients(struct discover_server *server)
  65         __attribute__((unused));
  66
  67 static void print_clients(struct discover_server *server)
  68 {
  69         struct client *client;
  70
  71         pb_log("current clients [%p,%p,%p]:\n",
  72                         &server->clients.head,
  73                         server->clients.head.prev,
  74                         server->clients.head.next);
  75         list_for_each_entry(&server->clients, client, list)
  76                 pb_log("\t[%p,%p,%p] client: %d\n", &client->list,
  77                                 client->list.prev, client->list.next,
  78                                 client->fd);
  79 }
  80
  81 static int client_write_message(
  82                 struct discover_server *server __attribute__((unused)),
  83                 struct client *client, struct pb_protocol_message *message)
  84 {
  85         int rc;
  86
  87         rc = pb_protocol_write_message(client->fd, message);
  88         if (rc)
  89                 talloc_free(client);
  90
  91         return rc;
  92 }
  93
  94 static int write_add_message(struct discover_server *server,
  95                 struct client *client, const struct device *dev)
  96 {
  97         struct pb_protocol_message *message;
  98         int len;
  99
 100         len = pb_protocol_device_len(dev);
 101
 102         message = pb_protocol_create_message(client,
 103                         PB_PROTOCOL_ACTION_ADD, len);
 104         if (!message)
 105                 return -1;
 106
 107         pb_protocol_serialise_device(dev, message->payload, len);
 108
 109         return client_write_message(server, client, message);
 110 }
 111
 112 static int write_remove_message(struct discover_server *server,
 113                 struct client *client, char *dev_id)
 114 {
 115         struct pb_protocol_message *message;
 116         int len;
 117
 118         len = strlen(dev_id) + sizeof(uint32_t);
 119
 120         message = pb_protocol_create_message(client,
 121                         PB_PROTOCOL_ACTION_REMOVE, len);
 122         if (!message)
 123                 return -1;
 124
 125         pb_protocol_serialise_string(message->payload, dev_id);
 126
 127         return client_write_message(server, client, message);
 128 }
 129
 130 static int discover_server_process_message(void *arg)
 131 {
 132         struct pb_protocol_message *message;
 133         struct client *client = arg;
 134
 135         message = pb_protocol_read_message(client, client->fd);
 136
 137         if (!message)
 138                 return 0;
 139
 140         if (message->action != PB_PROTOCOL_ACTION_BOOT) {
 141                 pb_log("%s: invalid action %d\n", __func__, message->action);
 142                 return 0;
 143         }
 144
 145         /* todo: process boot message */
 146         return 0;
 147 }
 148
 149 static int discover_server_process_connection(void *arg)
 150 {
 151         struct discover_server *server = arg;
 152         struct client *client;
 153         int fd, i, n_devices;
 154
 155         /* accept the incoming connection */
 156         fd = accept(server->socket, NULL, 0);
 157         if (!fd) {
 158                 pb_log("accept: %s\n", strerror(errno));
 159                 return 0;
 160         }
 161
 162         /* add to our list of clients */
 163         client = talloc(server, struct client);
 164         list_add(&server->clients, &client->list);
 165
 166         talloc_set_destructor(client, client_destructor);
 167
 168         client->fd = fd;
 169         client->server = server;
 170
 171         /* send existing devices to client */
 172         n_devices = device_handler_get_device_count(server->device_handler);
 173         for (i = 0; i < n_devices; i++) {
 174                 const struct device *device;
 175
 176                 device = device_handler_get_device(server->device_handler, i);
 177                 write_add_message(server, client, device);
 178         }
 179
 180         waiter_register(server->waitset, client->fd, WAIT_IN,
 181                         discover_server_process_message, client);
 182
 183         return 0;
 184 }
 185
 186 void discover_server_notify_add(struct discover_server *server,
 187                 struct device *device)
 188 {
 189         struct client *client;
 190
 191         list_for_each_entry(&server->clients, client, list)
 192                 write_add_message(server, client, device);
 193
 194 }
 195
 196 void discover_server_notify_remove(struct discover_server *server,
 197                 struct device *device)
 198 {
 199         struct client *client;
 200
 201         list_for_each_entry(&server->clients, client, list)
 202                 write_remove_message(server, client, device->id);
 203
 204 }
 205
 206 void discover_server_set_device_source(struct discover_server *server,
 207                 struct device_handler *handler)
 208 {
 209         server->device_handler = handler;
 210 }
 211
 212 struct discover_server *discover_server_init(struct waitset *waitset)
 213 {
 214         struct discover_server *server;
 215         struct sockaddr_un addr;
 216
 217         server = talloc(NULL, struct discover_server);
 218         if (!server)
 219                 return NULL;
 220
 221         server->waiter = NULL;
 222         server->waitset = waitset;
 223         list_init(&server->clients);
 224
 225         unlink(PB_SOCKET_PATH);
 226
 227         server->socket = socket(AF_UNIX, SOCK_STREAM, 0);
 228         if (server->socket < 0) {
 229                 pb_log("error creating server socket: %s\n", strerror(errno));
 230                 goto out_err;
 231         }
 232
 233         talloc_set_destructor(server, server_destructor);
 234
 235         addr.sun_family = AF_UNIX;
 236         strcpy(addr.sun_path, PB_SOCKET_PATH);
 237
 238         if (bind(server->socket, (struct sockaddr *)&addr, sizeof(addr))) {
 239                 pb_log("error binding server socket: %s\n", strerror(errno));
 240                 goto out_err;
 241         }
 242
 243         if (listen(server->socket, 8)) {
 244                 pb_log("server socket listen: %s\n", strerror(errno));
 245                 goto out_err;
 246         }
 247
 248         server->waiter = waiter_register(server->waitset, server->socket,
 249                         WAIT_IN, discover_server_process_connection, server);
 250
 251         return server;
 252
 253 out_err:
 254         talloc_free(server);
 255         return NULL;
 256 }
 257
 258 void discover_server_destroy(struct discover_server *server)
 259 {
 260         talloc_free(server);
 261 }
 262