1 files changed, 233 insertions, 0 deletions

diff --git a/src/service/regex/regex_api_search.c b/src/service/regex/regex_api_search.c
new file mode 100644
index 000000000..71219cbdd
--- /dev/null
+++ b/src/service/regex/regex_api_search.c
@@ -0,0 +1,233 @@
+/*
+     This file is part of GNUnet
+     Copyright (C) 2012, 2013, 2016 GNUnet e.V.
+
+     GNUnet is free software: you can redistribute it and/or modify it
+     under the terms of the GNU Affero General Public License as published
+     by the Free Software Foundation, either version 3 of the License,
+     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
+     Affero General Public License for more details.
+
+     You should have received a copy of the GNU Affero General Public License
+     along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+     SPDX-License-Identifier: AGPL3.0-or-later
+ */
+/**
+ * @file regex/regex_api_search.c
+ * @brief access regex service to discover
+ *        peers using matching strings
+ * @author Maximilian Szengel
+ * @author Christian Grothoff
+ */
+#include "platform.h"
+#include "gnunet_protocols.h"
+#include "gnunet_util_lib.h"
+#include "gnunet_regex_service.h"
+#include "regex_ipc.h"
+
+#define LOG(kind, ...) GNUNET_log_from (kind, "regex-api", __VA_ARGS__)
+
+
+/**
+ * Handle to store data about a regex search.
+ */
+struct GNUNET_REGEX_Search
+{
+  /**
+   * Connection to the regex service.
+   */
+  struct GNUNET_MQ_Handle *mq;
+
+  /**
+   * Our configuration.
+   */
+  const struct GNUNET_CONFIGURATION_Handle *cfg;
+
+  /**
+   * Function to call with results.
+   */
+  GNUNET_REGEX_Found callback;
+
+  /**
+   * Closure for @e callback.
+   */
+  void *callback_cls;
+
+  /**
+   * Search string to transmit to the service.
+   */
+  char *string;
+};
+
+
+/**
+ * (Re)connect to the REGEX service for the given search @a s.
+ *
+ * @param s context for the search search for
+ */
+static void
+search_reconnect (struct GNUNET_REGEX_Search *s);
+
+
+/**
+ * We got a response or disconnect after asking regex
+ * to do the search.  Check it is well-formed.
+ *
+ * @param cls the `struct GNUNET_REGEX_Search` to handle reply for
+ * @param result the message
+ * @return #GNUNET_SYSERR if @a rm is not well-formed.
+ */
+static int
+check_search_response (void *cls,
+                       const struct ResultMessage *result)
+{
+  uint16_t size = ntohs (result->header.size) - sizeof(*result);
+  uint16_t gpl = ntohs (result->get_path_length);
+  uint16_t ppl = ntohs (result->put_path_length);
+
+  if (size != (gpl + ppl) * sizeof(struct GNUNET_PeerIdentity))
+  {
+    GNUNET_break (0);
+    return GNUNET_SYSERR;
+  }
+  return GNUNET_OK;
+}
+
+
+/**
+ * We got a response or disconnect after asking regex
+ * to do the search.  Handle it.
+ *
+ * @param cls the `struct GNUNET_REGEX_Search` to handle reply for
+ * @param result the message
+ */
+static void
+handle_search_response (void *cls,
+                        const struct ResultMessage *result)
+{
+  struct GNUNET_REGEX_Search *s = cls;
+  uint16_t gpl = ntohs (result->get_path_length);
+  uint16_t ppl = ntohs (result->put_path_length);
+  const struct GNUNET_PeerIdentity *pid;
+
+  pid = &result->id;
+  LOG (GNUNET_ERROR_TYPE_DEBUG,
+       "Got regex result %s\n",
+       GNUNET_i2s (pid));
+  s->callback (s->callback_cls,
+               pid,
+               &pid[1],
+               gpl,
+               &pid[1 + gpl],
+               ppl);
+}
+
+
+/**
+ * We got a disconnect after asking regex to do the announcement.
+ * Retry.
+ *
+ * @param cls the `struct GNUNET_REGEX_Search` to retry
+ * @param error error code
+ */
+static void
+mq_error_handler (void *cls,
+                  enum GNUNET_MQ_Error error)
+{
+  struct GNUNET_REGEX_Search *s = cls;
+
+  GNUNET_MQ_destroy (s->mq);
+  s->mq = NULL;
+  search_reconnect (s);
+}
+
+
+/**
+ * (Re)connect to the REGEX service for the given search @a s.
+ *
+ * @param s context for the search search for
+ */
+static void
+search_reconnect (struct GNUNET_REGEX_Search *s)
+{
+  struct GNUNET_MQ_MessageHandler handlers[] = {
+    GNUNET_MQ_hd_var_size (search_response,
+                           GNUNET_MESSAGE_TYPE_REGEX_RESULT,
+                           struct ResultMessage,
+                           s),
+    GNUNET_MQ_handler_end ()
+  };
+  size_t slen = strlen (s->string) + 1;
+  struct GNUNET_MQ_Envelope *env;
+  struct RegexSearchMessage *rsm;
+
+  GNUNET_assert (NULL == s->mq);
+  s->mq = GNUNET_CLIENT_connect (s->cfg,
+                                 "regex",
+                                 handlers,
+                                 &mq_error_handler,
+                                 s);
+  if (NULL == s->mq)
+    return;
+  env = GNUNET_MQ_msg_extra (rsm,
+                             slen,
+                             GNUNET_MESSAGE_TYPE_REGEX_SEARCH);
+  GNUNET_memcpy (&rsm[1],
+                 s->string,
+                 slen);
+  GNUNET_MQ_send (s->mq,
+                  env);
+}
+
+
+struct GNUNET_REGEX_Search *
+GNUNET_REGEX_search (const struct GNUNET_CONFIGURATION_Handle *cfg,
+                     const char *string,
+                     GNUNET_REGEX_Found callback,
+                     void *callback_cls)
+{
+  struct GNUNET_REGEX_Search *s;
+  size_t slen = strlen (string) + 1;
+
+  if (slen + sizeof(struct RegexSearchMessage) >= GNUNET_MAX_MESSAGE_SIZE)
+  {
+    GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
+                _ ("Search string `%s' is too long!\n"),
+                string);
+    GNUNET_break (0);
+    return NULL;
+  }
+  LOG (GNUNET_ERROR_TYPE_DEBUG,
+       "Starting regex search for %s\n",
+       string);
+  s = GNUNET_new (struct GNUNET_REGEX_Search);
+  s->cfg = cfg;
+  s->string = GNUNET_strdup (string);
+  s->callback = callback;
+  s->callback_cls = callback_cls;
+  search_reconnect (s);
+  if (NULL == s->mq)
+  {
+    GNUNET_free (s->string);
+    GNUNET_free (s);
+    return NULL;
+  }
+  return s;
+}
+
+
+void
+GNUNET_REGEX_search_cancel (struct GNUNET_REGEX_Search *s)
+{
+  GNUNET_MQ_destroy (s->mq);
+  GNUNET_free (s->string);
+  GNUNET_free (s);
+}
+
+
+/* end of regex_api_search.c */