Imported Upstream version 0.9.2upstream/0.9.2

1 files changed, 645 insertions, 0 deletions

diff --git a/src/ats/ats_api_performance.c b/src/ats/ats_api_performance.c
new file mode 100644
index 0000000..848c7ec
--- /dev/null
+++ b/src/ats/ats_api_performance.c
@@ -0,0 +1,645 @@
+/*
+     This file is part of GNUnet.
+     (C) 2010,2011 Christian Grothoff (and other contributing authors)
+
+     GNUnet is free software; you can redistribute it and/or modify
+     it under the terms of the GNU General Public License as published
+     by the Free Software Foundation; either version 3, or (at your
+     option) any later version.
+
+     GNUnet is distributed in the hope that it will be useful, but
+     WITHOUT ANY WARRANTY; without even the implied warranty of
+     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+     General Public License for more details.
+
+     You should have received a copy of the GNU General Public License
+     along with GNUnet; see the file COPYING.  If not, write to the
+     Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+     Boston, MA 02111-1307, USA.
+*/
+/**
+ * @file ats/ats_api_performance.c
+ * @brief automatic transport selection and outbound bandwidth determination
+ * @author Christian Grothoff
+ * @author Matthias Wachs
+  */
+#include "platform.h"
+#include "gnunet_ats_service.h"
+#include "ats.h"
+
+
+/**
+ * Message in linked list we should send to the ATS service.  The
+ * actual binary message follows this struct.
+ */
+struct PendingMessage
+{
+
+  /**
+   * Kept in a DLL.
+   */
+  struct PendingMessage *next;
+
+  /**
+   * Kept in a DLL.
+   */
+  struct PendingMessage *prev;
+
+  /**
+   * Size of the message.
+   */
+  size_t size;
+
+  /**
+   * Is this the 'ATS_START' message?
+   */
+  int is_init;
+};
+
+
+/**
+ * Linked list of pending reservations.
+ */
+struct GNUNET_ATS_ReservationContext
+{
+
+  /**
+   * Kept in a DLL.
+   */
+  struct GNUNET_ATS_ReservationContext *next;
+
+  /**
+   * Kept in a DLL.
+   */
+  struct GNUNET_ATS_ReservationContext *prev;
+
+  /**
+   * Target peer.
+   */
+  struct GNUNET_PeerIdentity peer;
+
+  /**
+   * Desired reservation
+   */
+  int32_t size;
+
+  /**
+   * Function to call on result.
+   */
+  GNUNET_ATS_ReservationCallback rcb;
+
+  /**
+   * Closure for 'rcb'
+   */
+  void *rcb_cls;
+
+  /**
+   * Do we need to undo this reservation if it succeeded?  Set to
+   * GNUNET_YES if a reservation is cancelled.  (at that point, 'info'
+   * is also set to NULL; however, info will ALSO be NULL for the
+   * reservation context that is created to undo the original request,
+   * so 'info' being NULL cannot be used to check if undo is
+   * required).
+   */
+  int undo;
+};
+
+
+/**
+ * ATS Handle to obtain and/or modify performance information.
+ */
+struct GNUNET_ATS_PerformanceHandle
+{
+
+  /**
+   * Our configuration.
+   */
+  const struct GNUNET_CONFIGURATION_Handle *cfg;
+
+  /**
+   * Callback to invoke on performance changes.
+   */
+  GNUNET_ATS_PeerInformationCallback infocb;
+
+  /**
+   * Closure for 'infocb'.
+   */
+  void *infocb_cls;
+
+  /**
+   * Connection to ATS service.
+   */
+  struct GNUNET_CLIENT_Connection *client;
+
+  /**
+   * Head of list of messages for the ATS service.
+   */
+  struct PendingMessage *pending_head;
+
+  /**
+   * Tail of list of messages for the ATS service
+   */
+  struct PendingMessage *pending_tail;
+
+  /**
+   * Head of linked list of pending reservation requests.
+   */
+  struct GNUNET_ATS_ReservationContext *reservation_head;
+
+  /**
+   * Tail of linked list of pending reservation requests.
+   */
+  struct GNUNET_ATS_ReservationContext *reservation_tail;
+
+  /**
+   * Current request for transmission to ATS.
+   */
+  struct GNUNET_CLIENT_TransmitHandle *th;
+
+  /**
+   * Task to trigger reconnect.
+   */
+  GNUNET_SCHEDULER_TaskIdentifier task;
+
+};
+
+
+/**
+ * Re-establish the connection to the ATS service.
+ *
+ * @param ph handle to use to re-connect.
+ */
+static void
+reconnect (struct GNUNET_ATS_PerformanceHandle *ph);
+
+
+/**
+ * Re-establish the connection to the ATS service.
+ *
+ * @param cls handle to use to re-connect.
+ * @param tc scheduler context
+ */
+static void
+reconnect_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
+{
+  struct GNUNET_ATS_PerformanceHandle *ph = cls;
+
+  ph->task = GNUNET_SCHEDULER_NO_TASK;
+  reconnect (ph);
+}
+
+
+/**
+ * Transmit messages from the message queue to the service
+ * (if there are any, and if we are not already trying).
+ *
+ * @param ph handle to use
+ */
+static void
+do_transmit (struct GNUNET_ATS_PerformanceHandle *ph);
+
+
+/**
+ * We can now transmit a message to ATS. Do it.
+ *
+ * @param cls the 'struct GNUNET_ATS_SchedulingHandle'
+ * @param size number of bytes we can transmit to ATS
+ * @param buf where to copy the messages
+ * @return number of bytes copied into buf
+ */
+static size_t
+transmit_message_to_ats (void *cls, size_t size, void *buf)
+{
+  struct GNUNET_ATS_PerformanceHandle *ph = cls;
+  struct PendingMessage *p;
+  size_t ret;
+  char *cbuf;
+
+  ph->th = NULL;
+  ret = 0;
+  cbuf = buf;
+  while ((NULL != (p = ph->pending_head)) && (p->size <= size))
+  {
+    memcpy (&cbuf[ret], &p[1], p->size);
+    ret += p->size;
+    size -= p->size;
+    GNUNET_CONTAINER_DLL_remove (ph->pending_head, ph->pending_tail, p);
+    GNUNET_free (p);
+  }
+  do_transmit (ph);
+  return ret;
+}
+
+
+/**
+ * Transmit messages from the message queue to the service
+ * (if there are any, and if we are not already trying).
+ *
+ * @param ph handle to use
+ */
+static void
+do_transmit (struct GNUNET_ATS_PerformanceHandle *ph)
+{
+  struct PendingMessage *p;
+
+  if (NULL != ph->th)
+    return;
+  if (NULL == (p = ph->pending_head))
+    return;
+  if (NULL == ph->client)
+    return;                     /* currently reconnecting */
+  ph->th =
+      GNUNET_CLIENT_notify_transmit_ready (ph->client, p->size,
+                                           GNUNET_TIME_UNIT_FOREVER_REL,
+                                           GNUNET_YES, &transmit_message_to_ats,
+                                           ph);
+}
+
+
+/**
+ * We received a peer information message.  Validate and process it.
+ *
+ * @param ph our context with the callback
+ * @param msg the message
+ * @return GNUNET_OK if the message was well-formed
+ */
+static int
+process_pi_message (struct GNUNET_ATS_PerformanceHandle *ph,
+                    const struct GNUNET_MessageHeader *msg)
+{
+  const struct PeerInformationMessage *pi;
+  const struct GNUNET_ATS_Information *atsi;
+  const char *plugin_address;
+  const char *plugin_name;
+  struct GNUNET_HELLO_Address address;
+  uint16_t plugin_address_length;
+  uint16_t plugin_name_length;
+  uint32_t ats_count;
+
+  if (ph->infocb == NULL)
+  {
+    GNUNET_break (0);
+    return GNUNET_SYSERR;
+  }
+  if (ntohs (msg->size) < sizeof (struct PeerInformationMessage))
+  {
+    GNUNET_break (0);
+    return GNUNET_SYSERR;
+  }
+  pi = (const struct PeerInformationMessage *) msg;
+  ats_count = ntohl (pi->ats_count);
+  plugin_address_length = ntohs (pi->address_length);
+  plugin_name_length = ntohs (pi->plugin_name_length);
+  atsi = (const struct GNUNET_ATS_Information *) &pi[1];
+  plugin_address = (const char *) &atsi[ats_count];
+  plugin_name = &plugin_address[plugin_address_length];
+  if ((plugin_address_length + plugin_name_length +
+       ats_count * sizeof (struct GNUNET_ATS_Information) +
+       sizeof (struct PeerInformationMessage) != ntohs (msg->size)) ||
+      (ats_count >
+       GNUNET_SERVER_MAX_MESSAGE_SIZE / sizeof (struct GNUNET_ATS_Information))
+      || (plugin_name[plugin_name_length - 1] != '\0'))
+  {
+    GNUNET_break (0);
+    return GNUNET_SYSERR;
+  }
+  address.peer = pi->peer;
+  address.address = plugin_address;
+  address.address_length = plugin_address_length;
+  address.transport_name = plugin_name;
+  ph->infocb (ph->infocb_cls, &address, pi->bandwidth_out, pi->bandwidth_in,
+              atsi, ats_count);
+  return GNUNET_OK;
+}
+
+
+/**
+ * We received a reservation result message.  Validate and process it.
+ *
+ * @param ph our context with the callback
+ * @param msg the message
+ * @return GNUNET_OK if the message was well-formed
+ */
+static int
+process_rr_message (struct GNUNET_ATS_PerformanceHandle *ph,
+                    const struct GNUNET_MessageHeader *msg)
+{
+  const struct ReservationResultMessage *rr;
+  struct GNUNET_ATS_ReservationContext *rc;
+  int32_t amount;
+
+  if (ntohs (msg->size) < sizeof (struct ReservationResultMessage))
+  {
+    GNUNET_break (0);
+    return GNUNET_SYSERR;
+  }
+  rr = (const struct ReservationResultMessage *) msg;
+  amount = ntohl (rr->amount);
+  rc = ph->reservation_head;
+  if (0 != memcmp (&rr->peer, &rc->peer, sizeof (struct GNUNET_PeerIdentity)))
+  {
+    GNUNET_break (0);
+    return GNUNET_SYSERR;
+  }
+  GNUNET_CONTAINER_DLL_remove (ph->reservation_head, ph->reservation_tail, rc);
+  if ((amount == 0) || (rc->rcb != NULL))
+  {
+    /* tell client if not cancelled */
+    if (rc->rcb != NULL)
+      rc->rcb (rc->rcb_cls, &rr->peer, amount,
+               GNUNET_TIME_relative_ntoh (rr->res_delay));
+    GNUNET_free (rc);
+    return GNUNET_OK;
+  }
+  /* amount non-zero, but client cancelled, consider undo! */
+  if (GNUNET_YES != rc->undo)
+  {
+    GNUNET_free (rc);
+    return GNUNET_OK;           /* do not try to undo failed undos or negative amounts */
+  }
+  GNUNET_free (rc);
+  (void) GNUNET_ATS_reserve_bandwidth (ph, &rr->peer, -amount, NULL, NULL);
+  return GNUNET_OK;
+}
+
+
+/**
+ * Type of a function to call when we receive a message
+ * from the service.
+ *
+ * @param cls the 'struct GNUNET_ATS_SchedulingHandle'
+ * @param msg message received, NULL on timeout or fatal error
+ */
+static void
+process_ats_message (void *cls, const struct GNUNET_MessageHeader *msg)
+{
+  struct GNUNET_ATS_PerformanceHandle *ph = cls;
+
+  if (NULL == msg)
+    goto reconnect;
+  switch (ntohs (msg->type))
+  {
+  case GNUNET_MESSAGE_TYPE_ATS_PEER_INFORMATION:
+    if (GNUNET_OK != process_pi_message (ph, msg))
+      goto reconnect;
+    break;
+  case GNUNET_MESSAGE_TYPE_ATS_RESERVATION_RESULT:
+    if (GNUNET_OK != process_rr_message (ph, msg))
+      goto reconnect;
+    break;
+  default:
+    GNUNET_break (0);
+    goto reconnect;
+  }
+  GNUNET_CLIENT_receive (ph->client, &process_ats_message, ph,
+                         GNUNET_TIME_UNIT_FOREVER_REL);
+  return;
+reconnect:
+  GNUNET_CLIENT_disconnect (ph->client, GNUNET_NO);
+  ph->client = NULL;
+  ph->task =
+      GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_SECONDS, &reconnect_task,
+                                    ph);
+}
+
+
+/**
+ * Re-establish the connection to the ATS service.
+ *
+ * @param ph handle to use to re-connect.
+ */
+static void
+reconnect (struct GNUNET_ATS_PerformanceHandle *ph)
+{
+  struct PendingMessage *p;
+  struct ClientStartMessage *init;
+
+  GNUNET_assert (NULL == ph->client);
+  ph->client = GNUNET_CLIENT_connect ("ats", ph->cfg);
+  GNUNET_assert (NULL != ph->client);
+  GNUNET_CLIENT_receive (ph->client, &process_ats_message, ph,
+                         GNUNET_TIME_UNIT_FOREVER_REL);
+  if ((NULL == (p = ph->pending_head)) || (GNUNET_YES != p->is_init))
+  {
+    p = GNUNET_malloc (sizeof (struct PendingMessage) +
+                       sizeof (struct ClientStartMessage));
+    p->size = sizeof (struct ClientStartMessage);
+    p->is_init = GNUNET_YES;
+    init = (struct ClientStartMessage *) &p[1];
+    init->header.type = htons (GNUNET_MESSAGE_TYPE_ATS_START);
+    init->header.size = htons (sizeof (struct ClientStartMessage));
+    init->start_flag =
+        htonl ((ph->infocb ==
+                NULL) ? START_FLAG_PERFORMANCE_NO_PIC :
+               START_FLAG_PERFORMANCE_WITH_PIC);
+    GNUNET_CONTAINER_DLL_insert (ph->pending_head, ph->pending_tail, p);
+  }
+  do_transmit (ph);
+}
+
+
+
+/**
+ * Get handle to access performance API of the ATS subsystem.
+ *
+ * @param cfg configuration to use
+ * @param infocb function to call on allocation changes, can be NULL
+ * @param infocb_cls closure for infocb
+ * @return ats performance context
+ */
+struct GNUNET_ATS_PerformanceHandle *
+GNUNET_ATS_performance_init (const struct GNUNET_CONFIGURATION_Handle *cfg,
+                             GNUNET_ATS_PeerInformationCallback infocb,
+                             void *infocb_cls)
+{
+  struct GNUNET_ATS_PerformanceHandle *ph;
+
+  ph = GNUNET_malloc (sizeof (struct GNUNET_ATS_PerformanceHandle));
+  ph->cfg = cfg;
+  ph->infocb = infocb;
+  ph->infocb_cls = infocb_cls;
+  reconnect (ph);
+  return ph;
+}
+
+
+/**
+ * Client is done using the ATS performance subsystem, release resources.
+ *
+ * @param ph handle
+ */
+void
+GNUNET_ATS_performance_done (struct GNUNET_ATS_PerformanceHandle *ph)
+{
+  struct PendingMessage *p;
+  struct GNUNET_ATS_ReservationContext *rc;
+
+  while (NULL != (p = ph->pending_head))
+  {
+    GNUNET_CONTAINER_DLL_remove (ph->pending_head, ph->pending_tail, p);
+    GNUNET_free (p);
+  }
+  while (NULL != (rc = ph->reservation_head))
+  {
+    GNUNET_CONTAINER_DLL_remove (ph->reservation_head, ph->reservation_tail,
+                                 rc);
+    GNUNET_break (NULL == rc->rcb);
+    GNUNET_free (rc);
+  }
+  if (GNUNET_SCHEDULER_NO_TASK != ph->task)
+  {
+    GNUNET_SCHEDULER_cancel (ph->task);
+    ph->task = GNUNET_SCHEDULER_NO_TASK;
+  }
+  if (NULL != ph->client)
+  {
+    GNUNET_CLIENT_disconnect (ph->client, GNUNET_NO);
+    ph->client = NULL;
+  }
+  GNUNET_free (ph);
+}
+
+
+/**
+ * Reserve inbound bandwidth from the given peer.  ATS will look at
+ * the current amount of traffic we receive from the peer and ensure
+ * that the peer could add 'amount' of data to its stream.
+ *
+ * @param ph performance handle
+ * @param peer identifies the peer
+ * @param amount reserve N bytes for receiving, negative
+ *                amounts can be used to undo a (recent) reservation;
+ * @param rcb function to call with the resulting reservation information
+ * @param rcb_cls closure for info
+ * @return NULL on error
+ * @deprecated will be replaced soon
+ */
+struct GNUNET_ATS_ReservationContext *
+GNUNET_ATS_reserve_bandwidth (struct GNUNET_ATS_PerformanceHandle *ph,
+                              const struct GNUNET_PeerIdentity *peer,
+                              int32_t amount,
+                              GNUNET_ATS_ReservationCallback rcb, void *rcb_cls)
+{
+  struct GNUNET_ATS_ReservationContext *rc;
+  struct PendingMessage *p;
+  struct ReservationRequestMessage *m;
+
+  rc = GNUNET_malloc (sizeof (struct GNUNET_ATS_ReservationContext));
+  rc->size = amount;
+  rc->peer = *peer;
+  rc->rcb = rcb;
+  rc->rcb_cls = rcb_cls;
+  if ((rcb != NULL) && (amount > 0))
+    rc->undo = GNUNET_YES;
+  GNUNET_CONTAINER_DLL_insert_tail (ph->reservation_head, ph->reservation_tail,
+                                    rc);
+
+  p = GNUNET_malloc (sizeof (struct PendingMessage) +
+                     sizeof (struct ReservationRequestMessage));
+  p->size = sizeof (struct ReservationRequestMessage);
+  p->is_init = GNUNET_NO;
+  m = (struct ReservationRequestMessage *) &p[1];
+  m->header.type = htons (GNUNET_MESSAGE_TYPE_ATS_RESERVATION_REQUEST);
+  m->header.size = htons (sizeof (struct ReservationRequestMessage));
+  m->amount = htonl (amount);
+  m->peer = *peer;
+  GNUNET_CONTAINER_DLL_insert_tail (ph->pending_head, ph->pending_tail, p);
+  do_transmit (ph);
+  return rc;
+}
+
+
+/**
+ * Cancel request for reserving bandwidth.
+ *
+ * @param rc context returned by the original GNUNET_ATS_reserve_bandwidth call
+ */
+void
+GNUNET_ATS_reserve_bandwidth_cancel (struct GNUNET_ATS_ReservationContext *rc)
+{
+  rc->rcb = NULL;
+}
+
+
+/**
+ * Change preferences for the given peer. Preference changes are forgotten if peers
+ * disconnect.
+ *
+ * @param ph performance handle
+ * @param peer identifies the peer
+ * @param ... 0-terminated specification of the desired changes
+ */
+void
+GNUNET_ATS_change_preference (struct GNUNET_ATS_PerformanceHandle *ph,
+                              const struct GNUNET_PeerIdentity *peer, ...)
+{
+  struct PendingMessage *p;
+  struct ChangePreferenceMessage *m;
+  size_t msize;
+  uint32_t count;
+  struct PreferenceInformation *pi;
+  va_list ap;
+  enum GNUNET_ATS_PreferenceKind kind;
+
+  count = 0;
+  va_start (ap, peer);
+  while (GNUNET_ATS_PREFERENCE_END !=
+         (kind = va_arg (ap, enum GNUNET_ATS_PreferenceKind)))
+  {
+    switch (kind)
+    {
+    case GNUNET_ATS_PREFERENCE_BANDWIDTH:
+      count++;
+      (void) va_arg (ap, double);
+
+      break;
+    case GNUNET_ATS_PREFERENCE_LATENCY:
+      count++;
+      (void) va_arg (ap, double);
+
+      break;
+    default:
+      GNUNET_assert (0);
+    }
+  }
+  va_end (ap);
+  msize =
+      count * sizeof (struct PreferenceInformation) +
+      sizeof (struct ChangePreferenceMessage);
+  p = GNUNET_malloc (sizeof (struct PendingMessage) + msize);
+  p->size = msize;
+  p->is_init = GNUNET_NO;
+  m = (struct ChangePreferenceMessage *) &p[1];
+  m->header.type = htons (GNUNET_MESSAGE_TYPE_ATS_PREFERENCE_CHANGE);
+  m->header.size = htons (msize);
+  m->num_preferences = htonl (count);
+  m->peer = *peer;
+  pi = (struct PreferenceInformation *) &m[1];
+  count = 0;
+  va_start (ap, peer);
+  while (GNUNET_ATS_PREFERENCE_END !=
+         (kind = va_arg (ap, enum GNUNET_ATS_PreferenceKind)))
+  {
+    pi[count].preference_kind = htonl (kind);
+    switch (kind)
+    {
+    case GNUNET_ATS_PREFERENCE_BANDWIDTH:
+      pi[count].preference_value = (float) va_arg (ap, double);
+
+      count++;
+      break;
+    case GNUNET_ATS_PREFERENCE_LATENCY:
+      pi[count].preference_value = (float) va_arg (ap, double);
+
+      count++;
+      break;
+    default:
+      GNUNET_assert (0);
+    }
+  }
+  va_end (ap);
+  GNUNET_CONTAINER_DLL_insert_tail (ph->pending_head, ph->pending_tail, p);
+  do_transmit (ph);
+}
+
+/* end of ats_api_performance.c */