add compression support for bodies of POST/PUT operations

1 files changed, 105 insertions, 0 deletions

diff --git a/src/lib/teah_common.c b/src/lib/teah_common.c
new file mode 100644
index 000000000..8f994ef36
--- /dev/null
+++ b/src/lib/teah_common.c
@@ -0,0 +1,105 @@
+/*
+  This file is part of TALER
+  Copyright (C) 2019 GNUnet e.V.
+
+  TALER 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.
+
+  TALER 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 TALER; see the file COPYING.  If not, see
+  <http://www.gnu.org/licenses/>
+*/
+
+/**
+ * @file lib/teah_common.c
+ * @brief Helper routines shared by libtalerexchange and libtalerauditor
+ * @author Christian Grothoff
+ */
+#include "platform.h"
+#include "teah_common.h"
+
+#if COMPRESS_BODIES
+#include <zlib.h>
+#endif
+
+
+/**
+ * Add the @a body as POST data to the easy handle in
+ * @a ctx.
+ *
+ * @param ctx[in,out] a request context (updated)
+ * @param eh easy handle to use
+ * @param body JSON body to add to @e ctx
+ * @return #GNUNET_OK on success #GNUNET_SYSERR on failure
+ */
+int
+TEAH_curl_easy_post (struct TEAH_PostContext *ctx,
+                     CURL *eh,
+                     const json_t *body)
+{
+  char *str;
+  size_t slen;
+
+  str = json_dumps (body,
+                    JSON_COMPACT);
+  if (NULL == str)
+  {
+    GNUNET_break (0);
+    return GNUNET_SYSERR;
+  }
+  slen = strlen (str);
+#if COMPRESS_BODIES
+  {
+    Bytef *cbuf;
+    uLongf cbuf_size;
+    int ret;
+
+    cbuf_size = compressBound (slen);
+    cbuf = GNUNET_malloc (cbuf_size);
+    ret = compress (cbuf,
+                    &cbuf_size,
+                    (const Bytef *) str,
+                    slen);
+    if (Z_OK != ret)
+    {
+      /* compression failed!? */
+      GNUNET_break (0);
+      GNUNET_free (cbuf);
+      return GNUNET_SYSERR;
+    }
+    free (str);
+    slen = (size_t) cbuf_size;
+    ctx->json_enc = (char *) cbuf;
+  }
+#else
+  ctx->json_enc = str;
+#endif
+  GNUNET_assert (CURLE_OK ==
+                 curl_easy_setopt (eh,
+                                   CURLOPT_POSTFIELDS,
+                                   ctx->json_enc));
+  GNUNET_assert (CURLE_OK ==
+                 curl_easy_setopt (eh,
+                                   CURLOPT_POSTFIELDSIZE,
+                                   slen));
+  return GNUNET_OK;
+}
+
+
+/**
+ * Free the data in @a ctx.
+ *
+ * @param ctx[in] a request context (updated)
+ */
+void
+TEAH_curl_easy_post_finished (struct TEAH_PostContext *ctx)
+{
+  GNUNET_free_non_null (ctx->json_enc);
+}