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