git.ozlabs.org Git - petitboot/blob - ui/common/discover-client.c

   1
   2 #include <assert.h>
   3 #include <errno.h>
   4 #include <unistd.h>
   5 #include <stdlib.h>
   6 #include <stdio.h>
   7 #include <stdint.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 <log/log.h>
  15
  16 #include "discover-client.h"
  17 #include "pb-protocol/pb-protocol.h"
  18
  19 struct discover_client {
  20         int fd;
  21         struct discover_client_ops ops;
  22         int n_devices;
  23         struct device **devices;
  24 };
  25
  26 static int discover_client_destructor(void *arg)
  27 {
  28         struct discover_client *client = arg;
  29
  30         if (client->fd >= 0)
  31                 close(client->fd);
  32
  33         return 0;
  34 }
  35
  36 void discover_client_destroy(struct discover_client *client)
  37 {
  38         talloc_free(client);
  39 }
  40
  41 static struct device *find_device(struct discover_client *client,
  42                 const char *id)
  43 {
  44         int i;
  45
  46         for (i = 0; i < client->n_devices; i++) {
  47                 struct device *dev = client->devices[i];
  48                 if (!strcmp(dev->id, id))
  49                         return dev;
  50         }
  51
  52         return NULL;
  53 }
  54
  55 static void device_add(struct discover_client *client, struct device *device)
  56 {
  57         client->n_devices++;
  58         client->devices = talloc_realloc(client, client->devices,
  59                         struct device *, client->n_devices);
  60
  61         client->devices[client->n_devices - 1] = device;
  62         talloc_steal(client, device);
  63
  64         if (client->ops.device_add)
  65                 client->ops.device_add(device, client->ops.cb_arg);
  66 }
  67
  68 static void boot_option_add(struct discover_client *client,
  69                 struct boot_option *opt)
  70 {
  71         struct device *dev;
  72
  73         dev = find_device(client, opt->device_id);
  74
  75         /* we require that devices are already present before any boot options
  76          * are added */
  77         assert(dev);
  78
  79         talloc_steal(dev, opt);
  80
  81         if (client->ops.boot_option_add)
  82                 client->ops.boot_option_add(dev, opt, client->ops.cb_arg);
  83 }
  84
  85 static void device_remove(struct discover_client *client, const char *id)
  86 {
  87         struct device *device = NULL;
  88         int i;
  89
  90         for (i = 0; i < client->n_devices; i++) {
  91                 if (!strcmp(client->devices[i]->id, id)) {
  92                         device = client->devices[i];
  93                         break;
  94                 }
  95         }
  96
  97         if (!device)
  98                 return;
  99
 100         /* remove the device from the client's device array */
 101         client->n_devices--;
 102         memmove(&client->devices[i], &client->devices[i+1],
 103                         (client->n_devices - i) * sizeof(client->devices[0]));
 104         client->devices = talloc_realloc(client, client->devices,
 105                         struct device *, client->n_devices);
 106
 107         /* notify the UI */
 108         client->ops.device_remove(device, client->ops.cb_arg);
 109
 110         talloc_free(device);
 111 }
 112
 113 static int discover_client_process(void *arg)
 114 {
 115         struct discover_client *client = arg;
 116         struct pb_protocol_message *message;
 117         struct boot_option *opt;
 118         struct device *dev;
 119         char *dev_id;
 120         int rc;
 121
 122         message = pb_protocol_read_message(client, client->fd);
 123
 124         if (!message)
 125                 return -1;
 126
 127         switch (message->action) {
 128         case PB_PROTOCOL_ACTION_DEVICE_ADD:
 129                 dev = talloc_zero(client, struct device);
 130                 list_init(&dev->boot_options);
 131
 132                 rc = pb_protocol_deserialise_device(dev, message);
 133                 if (rc) {
 134                         pb_log("%s: no device?\n", __func__);
 135                         return 0;
 136                 }
 137
 138                 device_add(client, dev);
 139                 break;
 140         case PB_PROTOCOL_ACTION_BOOT_OPTION_ADD:
 141                 opt = talloc_zero(client, struct boot_option);
 142
 143                 rc = pb_protocol_deserialise_boot_option(opt, message);
 144                 if (rc) {
 145                         pb_log("%s: no boot_option?\n", __func__);
 146                         return 0;
 147                 }
 148
 149                 boot_option_add(client, opt);
 150                 break;
 151         case PB_PROTOCOL_ACTION_DEVICE_REMOVE:
 152                 dev_id = pb_protocol_deserialise_string(client, message);
 153                 if (!dev_id) {
 154                         pb_log("%s: no device id?\n", __func__);
 155                         return 0;
 156                 }
 157                 device_remove(client, dev_id);
 158                 break;
 159         default:
 160                 pb_log("%s: unknown action %d\n", __func__, message->action);
 161         }
 162
 163
 164         return 0;
 165 }
 166
 167 struct discover_client* discover_client_init(struct waitset *waitset,
 168         const struct discover_client_ops *ops, void *cb_arg)
 169 {
 170         struct discover_client *client;
 171         struct sockaddr_un addr;
 172
 173         client = talloc(NULL, struct discover_client);
 174         if (!client)
 175                 return NULL;
 176
 177         memcpy(&client->ops, ops, sizeof(client->ops));
 178         client->ops.cb_arg = cb_arg;
 179
 180         client->fd = socket(AF_UNIX, SOCK_STREAM, 0);
 181         if (client->fd < 0) {
 182                 pb_log("%s: socket: %s\n", __func__, strerror(errno));
 183                 goto out_err;
 184         }
 185
 186         talloc_set_destructor(client, discover_client_destructor);
 187
 188         client->n_devices = 0;
 189         client->devices = NULL;
 190
 191         addr.sun_family = AF_UNIX;
 192         strcpy(addr.sun_path, PB_SOCKET_PATH);
 193
 194         if (connect(client->fd, (struct sockaddr *)&addr, sizeof(addr))) {
 195                 pb_log("%s: connect: %s\n", __func__, strerror(errno));
 196                 goto out_err;
 197         }
 198
 199         waiter_register(waitset, client->fd, WAIT_IN, discover_client_process,
 200                         client);
 201
 202         return client;
 203
 204 out_err:
 205         talloc_free(client);
 206         return NULL;
 207 }
 208
 209 /* accessors for discovered devices */
 210 int discover_client_device_count(struct discover_client *client)
 211 {
 212         return client->n_devices;
 213 }
 214
 215 struct device *discover_client_get_device(struct discover_client *client,
 216                 int index)
 217 {
 218         if (index < 0 || index >= client->n_devices)
 219                 return NULL;
 220
 221         return client->devices[index];
 222 }
 223
 224 static void create_boot_command(struct boot_command *command,
 225                 const struct device *device __attribute__((unused)),
 226                 const struct boot_option *boot_option,
 227                 const struct pb_boot_data *data)
 228 {
 229
 230         command->option_id = boot_option->id;
 231         command->boot_image_file = data->image;
 232         command->initrd_file = data->initrd;
 233         command->boot_args = data->args;
 234 }
 235
 236 int discover_client_boot(struct discover_client *client,
 237                 const struct device *device,
 238                 const struct boot_option *boot_option,
 239                 const struct pb_boot_data *data)
 240 {
 241         struct pb_protocol_message *message;
 242         struct boot_command boot_command;
 243         int len, rc;
 244
 245         create_boot_command(&boot_command, device, boot_option, data);
 246
 247         len = pb_protocol_boot_len(&boot_command);
 248
 249         message = pb_protocol_create_message(client,
 250                         PB_PROTOCOL_ACTION_BOOT, len);
 251
 252         if (!message)
 253                 return -1;
 254
 255         pb_protocol_serialise_boot_command(&boot_command,
 256                         message->payload, len);
 257
 258         rc = pb_protocol_write_message(client->fd, message);
 259
 260         return rc;
 261 }