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Diffstat (limited to 'src/json/json_helper.c')
-rw-r--r-- | src/json/json_helper.c | 146 |
1 files changed, 146 insertions, 0 deletions
diff --git a/src/json/json_helper.c b/src/json/json_helper.c new file mode 100644 index 000000000..b61fe21a6 --- /dev/null +++ b/src/json/json_helper.c @@ -0,0 +1,146 @@ +/* + This file is part of TALER + Copyright (C) 2014, 2015, 2016 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, If not, see <http://www.gnu.org/licenses/> +*/ +/** + * @file json/json_helper.c + * @brief helper functions to generate specifications to parse + * Taler-specific JSON objects with libgnunetjson + * @author Sree Harsha Totakura <sreeharsha@totakura.in> + * @author Christian Grothoff + */ +#include "platform.h" +#include <gnunet/gnunet_util_lib.h> +#include "taler_util.h" +#include "taler_json_lib.h" + + +/** + * Convert a TALER amount to a JSON object. + * + * @param amount the amount + * @return a json object describing the amount + */ +json_t * +TALER_JSON_from_amount (const struct TALER_Amount *amount) +{ + json_t *j; + + if ( (amount->value != (uint64_t) ((json_int_t) amount->value)) || + (0 > ((json_int_t) amount->value)) ) + { + /* Theoretically, json_int_t can be a 32-bit "long", or we might + have a 64-bit value which converted to a 63-bit signed long + long causes problems here. So we check. Note that depending + on the platform, the compiler may be able to statically tell + that at least the first check is always false. */ + GNUNET_break (0); + return NULL; + } + j = json_pack ("{s:s, s:I, s:I}", + "currency", amount->currency, + "value", (json_int_t) amount->value, + "fraction", (json_int_t) amount->fraction); + GNUNET_assert (NULL != j); + return j; +} + + +/** + * Parse given JSON object to Amount + * + * @param cls closure, NULL + * @param root the json object representing data + * @param[out] spec where to write the data + * @return #GNUNET_OK upon successful parsing; #GNUNET_SYSERR upon error + */ +static int +parse_amount (void *cls, + json_t *root, + struct GNUNET_JSON_Specification *spec) +{ + struct TALER_Amount *r_amount = spec->ptr; + json_int_t value; + json_int_t fraction; + const char *currency; + + memset (r_amount, + 0, + sizeof (struct TALER_Amount)); + if (0 != json_unpack (root, + "{s:I, s:I, s:s}", + "value", &value, + "fraction", &fraction, + "currency", ¤cy)) + { + char *json_enc; + + if (NULL == (json_enc = json_dumps (root, + JSON_COMPACT | JSON_ENCODE_ANY))) + { + GNUNET_break (0); + return GNUNET_SYSERR; + } + GNUNET_log (GNUNET_ERROR_TYPE_WARNING, + "Malformed JSON amount: %s\n", + json_enc); + free (json_enc); + return GNUNET_SYSERR; + } + if ( (value < 0) || + (fraction < 0) || + (value > UINT64_MAX) || + (fraction > UINT32_MAX) ) + { + GNUNET_break_op (0); + return GNUNET_SYSERR; + } + if (strlen (currency) >= TALER_CURRENCY_LEN) + { + GNUNET_break_op (0); + return GNUNET_SYSERR; + } + r_amount->value = (uint64_t) value; + r_amount->fraction = (uint32_t) fraction; + strcpy (r_amount->currency, currency); + (void) TALER_amount_normalize (r_amount); + return GNUNET_OK; +} + + + +/** + * Provide specification to parse given JSON object to an amount. + * + * @param name name of the amount field in the JSON + * @param[out] r_amount where the amount has to be written + */ +struct GNUNET_JSON_Specification +TALER_JSON_spec_amount (const char *name, + struct TALER_Amount *r_amount) +{ + struct GNUNET_JSON_Specification ret = { + .parser = &parse_amount, + .cleaner = NULL, + .cls = NULL, + .field = name, + .ptr = r_amount, + .ptr_size = 0, + .size_ptr = NULL + }; + return ret; +} + + +/* end of json/json_helper.c */ |