adding libgnunetcurl

1 files changed, 155 insertions, 0 deletions

diff --git a/src/include/gnunet_curl_lib.h b/src/include/gnunet_curl_lib.h
new file mode 100644
index 000000000..098b4dc37
--- /dev/null
+++ b/src/include/gnunet_curl_lib.h
@@ -0,0 +1,155 @@
+/*
+  This file is part of GNUnet
+  Copyright (C) 2014, 2015, 2016 GNUnet e.V.
+
+  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, If not, see
+  <http://www.gnu.org/licenses/>
+*/
+/**
+ * @file src/include/gnunet_curl_lib.h
+ * @brief library to make it easy to download JSON replies over HTTP
+ * @author Sree Harsha Totakura <sreeharsha@totakura.in>
+ * @author Christian Grothoff
+ *
+ * @defgroup curl CURL integration library
+ * Download JSON using libcurl.
+ * @{
+ */
+#ifndef GNUNET_CURL_LIB_H
+#define GNUNET_CURL_LIB_H
+#include <curl/curl.h>
+#include <jansson.h>
+#include <gnunet/gnunet_util_lib.h>
+
+
+/**
+ * Initialise this library.  This function should be called before using any of
+ * the following functions.
+ *
+ * @return library context
+ */
+struct GNUNET_CURL_Context *
+GNUNET_CURL_init (void);
+
+
+/**
+ * Obtain the information for a select() call to wait until
+ * #GNUNET_CURL_perform() is ready again.  Note that calling
+ * any other TALER_EXCHANGE-API may also imply that the library
+ * is again ready for #GNUNET_CURL_perform().
+ *
+ * Basically, a client should use this API to prepare for select(),
+ * then block on select(), then call #GNUNET_CURL_perform() and then
+ * start again until the work with the context is done.
+ *
+ * This function will NOT zero out the sets and assumes that @a max_fd
+ * and @a timeout are already set to minimal applicable values.  It is
+ * safe to give this API FD-sets and @a max_fd and @a timeout that are
+ * already initialized to some other descriptors that need to go into
+ * the select() call.
+ *
+ * @param ctx context to get the event loop information for
+ * @param read_fd_set will be set for any pending read operations
+ * @param write_fd_set will be set for any pending write operations
+ * @param except_fd_set is here because curl_multi_fdset() has this argument
+ * @param max_fd set to the highest FD included in any set;
+ *        if the existing sets have no FDs in it, the initial
+ *        value should be "-1". (Note that `max_fd + 1` will need
+ *        to be passed to select().)
+ * @param timeout set to the timeout in milliseconds (!); -1 means
+ *        no timeout (NULL, blocking forever is OK), 0 means to
+ *        proceed immediately with #GNUNET_CURL_perform().
+ */
+void
+GNUNET_CURL_get_select_info (struct GNUNET_CURL_Context *ctx,
+                             fd_set *read_fd_set,
+                             fd_set *write_fd_set,
+                             fd_set *except_fd_set,
+                             int *max_fd,
+                             long *timeout);
+
+
+/**
+ * Run the main event loop for the Taler interaction.
+ *
+ * @param ctx the library context
+ */
+void
+GNUNET_CURL_perform (struct GNUNET_CURL_Context *ctx);
+
+
+/**
+ * Cleanup library initialisation resources.  This function should be called
+ * after using this library to cleanup the resources occupied during library's
+ * initialisation.
+ *
+ * @param ctx the library context
+ */
+void
+GNUNET_CURL_fini (struct GNUNET_CURL_Context *ctx);
+
+
+/**
+ * Entry in the context's job queue.
+ */
+struct GNUNET_CURL_Job;
+
+/**
+ * Function to call upon completion of a job.
+ *
+ * @param cls closure
+ * @param response_code HTTP response code from server, 0 on hard error
+ * @param json response, NULL if response was not in JSON format
+ */
+typedef void
+(*GNUNET_CURL_JobCompletionCallback)(void *cls,
+                                     long response_code,
+                                     json_t *json);
+
+
+/**
+ * Schedule a CURL request to be executed and call the given @a jcc
+ * upon its completion. Note that the context will make use of the
+ * CURLOPT_PRIVATE facility of the CURL @a eh.
+ *
+ * This function modifies the CURL handle to add the
+ * "Content-Type: application/json" header if @a add_json is set.
+ *
+ * @param ctx context to execute the job in
+ * @param eh curl easy handle for the request, will
+ *           be executed AND cleaned up
+ * @param add_json add "application/json" content type header
+ * @param jcc callback to invoke upon completion
+ * @param jcc_cls closure for @a jcc
+ * @return NULL on error (in this case, @eh is still released!)
+ */
+struct GNUNET_CURL_Job *
+GNUNET_CURL_job_add (struct GNUNET_CURL_Context *ctx,
+                     CURL *eh,
+                     int add_json,
+                     GNUNET_CURL_JobCompletionCallback jcc,
+                     void *jcc_cls);
+
+
+/**
+ * Cancel a job.  Must only be called before the job completion
+ * callback is called for the respective job.
+ *
+ * @param job job to cancel
+ */
+void
+GNUNET_CURL_job_cancel (struct GNUNET_CURL_Job *job);
+
+#endif
+/** @} */  /* end of group */
+
+/* end of gnunet_curl_lib.h */