return ret;
}
+/**
+ * Format and send an error message to the command handler.
+ *
+ * To pass an error message from the callback of an afs command to the client,
+ * this function should be called. It formats the message into a buffer which
+ * is passed as a shared memory area to the command handler from where it
+ * propagates to the client.
+ *
+ * The message will be tagged with the ERROR_LOG sideband designator so that
+ * the client writes it to its stderr stream rather than to stdout as with
+ * aca->pbout. In analogy to the default Unix semantics of stderr, the message
+ * is sent without buffering.
+ *
+ * If sending the error message fails, an error is logged on the server side,
+ * but no other action is taken.
+ *
+ * \param aca Used to obtain the fd to send the shmid to.
+ * \param fmt Usual format string.
+ */
+__printf_2_3 void afs_error(const struct afs_callback_arg *aca,
+ const char *fmt,...)
+{
+ va_list argp;
+ char *msg;
+ unsigned n;
+ int ret;
+
+ va_start(argp, fmt);
+ n = xvasprintf(&msg, fmt, argp);
+ va_end(argp);
+ ret = pass_buffer_as_shm(aca->fd, SBD_ERROR_LOG, msg, n + 1);
+ if (ret < 0)
+ PARA_ERROR_LOG("Could not send %s: %s\n", msg,
+ para_strerror(-ret));
+ free(msg);
+}
+
static int call_callback(int fd, int query_shmid)
{
void *query_shm;
/* ignore subsequent errors (but log them) */
if (current_mop && strcmp(current_mop, arg) != 0) {
int ret2;
- para_printf(&aca->pbout, "switching back to %s\n", current_mop);
+ afs_error(aca, "switching back to %s\n", current_mop);
ret2 = activate_mood_or_playlist(current_mop, &aca->pbout);
if (ret2 >= 0)
goto free_lpr;
- para_printf(&aca->pbout, "could not reactivate %s: %s\n",
- current_mop, para_strerror(-ret2));
+ afs_error(aca, "could not reactivate %s: %s\n", current_mop,
+ para_strerror(-ret2));
}
activate_mood_or_playlist(NULL, &aca->pbout);
free_lpr:
continue;
ret = t->ops->create(database_dir);
if (ret < 0) {
- para_printf(&aca->pbout, "cannot create table %s\n",
- t->name);
+ afs_error(aca, "cannot create table %s\n", t->name);
goto out;
}
para_printf(&aca->pbout, "successfully created %s table\n",
}
ret = open_afs_tables();
if (ret < 0)
- para_printf(&aca->pbout, "cannot open afs tables: %s\n",
+ afs_error(aca, "cannot open afs tables: %s\n",
para_strerror(-ret));
out:
return ret;