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