stuff

1 files changed, 420 insertions, 0 deletions

diff --git a/src/fs/gnunet-service-fs_lc.c b/src/fs/gnunet-service-fs_lc.c
new file mode 100644
index 000000000..2113a4498
--- /dev/null
+++ b/src/fs/gnunet-service-fs_lc.c
@@ -0,0 +1,420 @@
+/*
+     This file is part of GNUnet.
+     (C) 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 fs/gnunet-service-fs_lc.c
+ * @brief API to handle 'connected peers'
+ * @author Christian Grothoff
+ */
+
+#include "platform.h"
+#include "gnunet-service-fs_lc.h"
+
+
+/**
+ * Doubly-linked list of requests we are performing
+ * on behalf of the same client.
+ */
+struct ClientRequest
+{
+
+  /**
+   * This is a doubly-linked list.
+   */
+  struct ClientRequest *next;
+
+  /**
+   * This is a doubly-linked list.
+   */
+  struct ClientRequest *prev;
+
+  /**
+   * Request this entry represents.
+   */
+  struct GSF_PendingRequest *pr;
+
+  /**
+   * Client list this request belongs to.
+   */
+  struct GSF_LocalClient *lc;
+
+};
+
+
+
+/**
+ * Replies to be transmitted to the client.  The actual
+ * response message is allocated after this struct.
+ */
+struct ClientResponse
+{
+  /**
+   * This is a doubly-linked list.
+   */
+  struct ClientResponse *next;
+
+  /**
+   * This is a doubly-linked list.
+   */
+  struct ClientResponse *prev;
+
+  /**
+   * Client list entry this response belongs to.
+   */
+  struct GSF_LocalClient *lc;
+
+  /**
+   * Number of bytes in the response.
+   */
+  size_t msize;
+};
+
+
+
+/**
+ * A local client.
+ */
+struct GSF_LocalClient
+{
+
+  /**
+   * We keep clients in a DLL.
+   */
+  struct GSF_LocalClient *next;
+
+  /**
+   * We keep clients in a DLL.
+   */
+  struct GSF_LocalClient *prev;
+
+  /**
+   * ID of the client.
+   */
+  struct GNUNET_SERVER_Client *client;
+
+  /**
+   * Head of list of requests performed on behalf
+   * of this client right now.
+   */
+  struct ClientRequest *cr_head;
+
+  /**
+   * Tail of list of requests performed on behalf
+   * of this client right now.
+   */
+  struct ClientRequest *cr_tail;
+
+  /**
+   * Head of linked list of responses.
+   */
+  struct ClientResponse *res_head;
+
+  /**
+   * Tail of linked list of responses.
+   */
+  struct ClientResponse *res_tail;
+
+  /**
+   * Context for sending replies.
+   */
+  struct GNUNET_CONNECTION_TransmitHandle *th;
+
+};
+
+
+/**
+ * Head of linked list of our local clients.
+ */
+static struct GSF_LocalClient *client_head;
+
+
+/**
+ * Head of linked list of our local clients.
+ */
+static struct GSF_LocalClient *client_tail;
+
+
+/**
+ * Look up a local client record or create one if it
+ * doesn't exist yet.
+ *
+ * @param client handle of the client
+ * @return handle to local client entry
+ */
+struct GSF_LocalClient *
+GSF_local_client_lookup_ (struct GNUNET_SERVER_Client *client)
+{
+  struct GSF_LocalClient *pos;
+
+  pos = client_head;
+  while ( (pos != NULL) &&
+          (pos->client != client) )
+    pos = pos->next;
+  if (pos != NULL)
+    return pos;
+  pos = GNUNET_malloc (sizeof (struct GSF_LocalClient));
+  pos->client = client;
+  GNUNET_CONTAINER_DLL_insert (client_head,
+                               client_tail,
+                               pos);
+  return pos;
+}
+
+
+/**
+ * Handle START_SEARCH-message (search request from local client).
+ *
+ * @param cls closure
+ * @param client identification of the client
+ * @param message the actual message
+ */
+void
+GSF_local_client_start_search_handler_ (void *cls,
+                                        struct GNUNET_SERVER_Client *client,
+                                        const struct GNUNET_MessageHeader *message)
+{
+  static GNUNET_HashCode all_zeros;
+  const struct SearchMessage *sm;
+  struct GSF_LocalClient *lc;
+  struct ClientRequest *cr;
+  struct GSF_PendingRequest *pr;
+  uint16_t msize;
+  unsigned int sc;
+  enum GNUNET_BLOCK_Type type;
+  enum GSF_PendingRequestOptions options;
+
+  msize = ntohs (message->size);
+  if ( (msize < sizeof (struct SearchMessage)) ||
+       (0 != (msize - sizeof (struct SearchMessage)) % sizeof (GNUNET_HashCode)) )
+    {
+      GNUNET_break (0);
+      GNUNET_SERVER_receive_done (client,
+                                  GNUNET_SYSERR);
+      return;
+    }
+  GNUNET_STATISTICS_update (stats,
+                            gettext_noop ("# client searches received"),
+                            1,
+                            GNUNET_NO);
+  sc = (msize - sizeof (struct SearchMessage)) / sizeof (GNUNET_HashCode);
+  sm = (const struct SearchMessage*) message;
+  type = ntohl (sm->type);
+#if DEBUG_FS
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "Received request for `%s' of type %u from local client\n",
+              GNUNET_h2s (&sm->query),
+              (unsigned int) type);
+#endif
+  lc = GSF_local_client_lookup_ (client);
+
+
+  /* detect duplicate KBLOCK requests */
+  if ( (type == GNUNET_BLOCK_TYPE_FS_KBLOCK) ||
+       (type == GNUNET_BLOCK_TYPE_FS_NBLOCK) ||
+       (type == GNUNET_BLOCK_TYPE_ANY) )
+    {
+      cr = lc->cr_head;
+      while ( (cl != NULL) &&
+              ( (0 != memcmp (GSF_pending_request_get_query_ (cr->pr),
+                              &sm->query,
+                              sizeof (GNUNET_HashCode))) ||
+                (GSF_pending_request_get_type_ (cr->pr) != type) ) )
+        cr = cr->next;
+      if (crl != NULL)  
+        { 
+#if DEBUG_FS
+          GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+                      "Have existing request, merging content-seen lists.\n");
+#endif
+          GSF_pending_request_update_ (cr->pr,
+                                       &sm[1],
+                                       sc);
+          GNUNET_STATISTICS_update (stats,
+                                    gettext_noop ("# client searches updated (merged content seen list)"),
+                                    1,
+                                    GNUNET_NO);
+          GNUNET_SERVER_receive_done (client,
+                                      GNUNET_OK);
+          return;
+        }
+    }
+
+  GNUNET_STATISTICS_update (stats,
+                            gettext_noop ("# client searches active"),
+                            1,
+                            GNUNET_NO);
+  cr = GNUNET_malloc (sizeof (struct ClientRequest));
+  cr->lc = lc;
+  GNUNET_CONTAINER_DLL_insert (lc->cr_head,
+                               lc->cr_tail,
+                               cr);
+  options = GSF_PRO_LOCAL_REQUEST;  
+  if (0 != (1 & ntohl (sm->options)))
+    options |= GSF_PRO_LOCAL_ONLY;
+  cr->pr = GSF_pending_request_create (options,
+                                       
+                                       type,
+                                       &sm->query,
+                                       (type == GNUNET_BLOCK_TYPE_SBLOCK)
+                                       ? &sm->target /* namespace */
+                                       : NULL,
+                                       (0 != memcmp (&sm->target,
+                                                     &all_zeros,
+                                                     sizeof (GNUNET_HashCode)))
+                                       ? &sm->target,
+                                       : NULL,
+                                       NULL /* bf */, 0 /* mingle */,
+                                       ntohl (sm->anonymity_level),
+                                       0 /* priority */,
+                                       &sm[1], sc,
+                                       &client_response_handler,
+                                       cr);
+  // FIXME: start local processing and/or P2P processing?
+}
+
+
+/**
+ * Transmit the given message by copying it to the target buffer
+ * "buf".  "buf" will be NULL and "size" zero if the socket was closed
+ * for writing in the meantime.  In that case, do nothing
+ * (the disconnect or shutdown handler will take care of the rest).
+ * If we were able to transmit messages and there are still more
+ * pending, ask core again for further calls to this function.
+ *
+ * @param cls closure, pointer to the 'struct GSF_LocalClient'
+ * @param size number of bytes available in buf
+ * @param buf where the callee should write the message
+ * @return number of bytes written to buf
+ */
+static size_t
+transmit_to_client (void *cls,
+                    size_t size,
+                    void *buf)
+{
+  struct GSF_LocalClient *lc = cls;
+  char *cbuf = buf;
+  struct ClientResponse *res;
+  size_t msize;
+  
+  cl->th = NULL;
+  if (NULL == buf)
+    return 0;
+  msize = 0;
+  while ( (NULL != (res = lc->res_head) ) &&
+          (res->msize <= size) )
+    {
+      memcpy (&cbuf[msize], &res[1], res->msize);
+      msize += res->msize;
+      size -= res->msize;
+      GNUNET_CONTAINER_DLL_remove (cl->res_head,
+                                   cl->res_tail,
+                                   res);
+      GNUNET_free (res);
+    }
+  if (NULL != res)
+    lc->th = GNUNET_SERVER_notify_transmit_ready (lc->client,
+                                                  res->msize,
+                                                  GNUNET_TIME_UNIT_FOREVER_REL,
+                                                  &transmit_to_client,
+                                                  lc);
+  return msize;
+}
+
+
+/**
+ * Transmit a message to the given local client as soon as possible.
+ * If the client disconnects before transmission, the message is
+ * simply discarded.
+ *
+ * @param lc recipient
+ * @param msg message to transmit to client
+ */
+void
+GSF_local_client_transmit_ (struct GSF_LocalClient *lc,
+                            const struct GNUNET_MessageHeader *msg)
+{
+  struct ClientResponse *res;
+  size_t msize;
+
+  msize = ntohs (msg->size);
+  res = GNUNET_malloc (sizeof (struct ClientResponse) + msize);
+  res->lc = lc;
+  res->msize = msize;
+  GNUNET_CONTAINER_DLL_insert_tail (lc->res_head,
+                                    lc->res_tail,
+                                    res);
+  if (NULL == lc->tc)
+    lc->tc = GNUNET_CLIENT_notify_transmit_ready (lc->client,
+                                                  msize,
+                                                  GNUNET_TIME_UNIT_FOREVER_REL,
+                                                  GNUNET_NO,
+                                                  &transmit_to_client,
+                                                  lc);
+}
+
+
+/**
+ * A client disconnected from us.  Tear down the local client
+ * record.
+ *
+ * @param cls unused
+ * @param client handle of the client
+ */
+void
+GSF_client_disconnect_handler_ (void *cls,
+                                const struct GNUNET_SERVER_Client *client)
+{
+  struct GSF_LocalClient *pos;
+  struct DisconnectCallback *dc;
+  struct ClientRequest *cr;
+  struct ClientResponse *res;
+
+  pos = client_head;
+  while ( (pos != NULL) &&
+          (pos->client != client) )
+    pos = pos->next;
+  if (pos == NULL)
+    return pos;
+  while (NULL != (cr = pos->cr_head))
+    {      
+      GNUNET_CONTAINER_DLL_remove (pos->cr_head,
+                                   pos->cr_tail,
+                                   cr);
+      GSF_pending_request_cancel_ (cr->pr);
+      GNUNET_free (cr);
+    }
+  while (NULL != (res = pos->res_head))
+    {
+      GNUNET_CONTAINER_DLL_remove (pos->res_head,
+                                   pos->res_tail,
+                                   res);
+      GNUNET_free (res);
+    }
+  if (pos->th != NULL)
+    {
+      GNUNET_CONNECTION_notify_transmit_ready_cancel (pos->th);
+      pos->th = NULL;
+    }
+  GSF_handle_local_client_disconnect_ (pos);
+  GNUNET_free (pos);
+}
+
+
+/* end of gnunet-service-fs_lc.c */