1 files changed, 161 insertions, 0 deletions

diff --git a/src/lib/json/json.c b/src/lib/json/json.c
new file mode 100644
index 000000000..07ec158be
--- /dev/null
+++ b/src/lib/json/json.c
@@ -0,0 +1,161 @@
+/*
+   This file is part of GNUnet
+   Copyright (C) 2014-2017, 2021, 2022 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 json/json.c
+ * @brief functions to parse JSON snippets
+ * @author Florian Dold
+ * @author Benedikt Mueller
+ * @author Christian Grothoff
+ */
+#include "platform.h"
+#include "gnunet_json_lib.h"
+
+
+enum GNUNET_GenericReturnValue
+GNUNET_JSON_parse (const json_t *root,
+                   struct GNUNET_JSON_Specification *spec,
+                   const char **error_json_name,
+                   unsigned int *error_line)
+{
+  if (NULL == root)
+    return GNUNET_SYSERR;
+  for (unsigned int i = 0; NULL != spec[i].parser; i++)
+  {
+    json_t *pos;
+
+    if (NULL == spec[i].field)
+      pos = (json_t *) root;
+    else
+      pos = json_object_get (root,
+                             spec[i].field);
+    if ( ( (NULL == pos) ||
+           (json_is_null (pos) ) ) &&
+         (spec[i].is_optional) )
+    {
+      if (NULL != spec[i].missing)
+        *spec[i].missing = true;
+      continue;
+    }
+    if ( (NULL == pos) ||
+         (GNUNET_OK !=
+          spec[i].parser (spec[i].cls,
+                          pos,
+                          &spec[i])) )
+    {
+      if (NULL != error_json_name)
+        *error_json_name = spec[i].field;
+      else
+        GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
+                    "Parsing failed for field `%s:%u`\n",
+                    spec[i].field,
+                    i);
+      if (NULL != error_line)
+        *error_line = i;
+      GNUNET_JSON_parse_free (spec);
+      return GNUNET_SYSERR;
+    }
+    if (NULL != spec[i].missing)
+      *spec[i].missing = false;
+  }
+  return GNUNET_OK; /* all OK! */
+}
+
+
+struct GNUNET_JSON_Specification
+GNUNET_JSON_spec_mark_optional (struct GNUNET_JSON_Specification spec,
+                                bool *missing)
+{
+  struct GNUNET_JSON_Specification ret = spec;
+
+  ret.is_optional = true;
+  ret.missing = missing;
+  return ret;
+}
+
+
+void
+GNUNET_JSON_parse_free (struct GNUNET_JSON_Specification *spec)
+{
+  for (unsigned int i = 0; NULL != spec[i].parser; i++)
+    if (NULL != spec[i].cleaner)
+      spec[i].cleaner (spec[i].cls,
+                       &spec[i]);
+}
+
+
+/**
+ * Set an option with a JSON value from the command line.
+ * A pointer to this function should be passed as part of the
+ * 'struct GNUNET_GETOPT_CommandLineOption' array to initialize options
+ * of this type.
+ *
+ * @param ctx command line processing context
+ * @param scls additional closure (will point to the 'json_t *')
+ * @param option name of the option
+ * @param value actual value of the option as a string.
+ * @return #GNUNET_OK if parsing the value worked
+ */
+static enum GNUNET_GenericReturnValue
+set_json (struct GNUNET_GETOPT_CommandLineProcessorContext *ctx,
+          void *scls,
+          const char *option,
+          const char *value)
+{
+  json_t **json = scls;
+  json_error_t error;
+
+  *json = json_loads (value,
+                      JSON_REJECT_DUPLICATES,
+                      &error);
+  if (NULL == *json)
+  {
+    fprintf (stderr,
+             _ ("Failed to parse JSON in option `%s': %s (%s)\n"),
+             option,
+             error.text,
+             error.source);
+    return GNUNET_SYSERR;
+  }
+  return GNUNET_OK;
+}
+
+
+struct GNUNET_GETOPT_CommandLineOption
+GNUNET_JSON_getopt (char shortName,
+                    const char *name,
+                    const char *argumentHelp,
+                    const char *description,
+                    json_t **json)
+{
+  struct GNUNET_GETOPT_CommandLineOption clo = {
+    .shortName = shortName,
+    .name = name,
+    .argumentHelp = argumentHelp,
+    .description = description,
+    .require_argument = 1,
+    .processor = &set_json,
+    .scls = (void *) json
+  };
+
+  return clo;
+}
+
+
+/* end of json.c */