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