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Diffstat (limited to 'json-glib/json-builder.c')
| -rw-r--r-- | json-glib/json-builder.c | 682 |
1 files changed, 682 insertions, 0 deletions
diff --git a/json-glib/json-builder.c b/json-glib/json-builder.c new file mode 100644 index 0000000..ea9bc05 --- /dev/null +++ b/json-glib/json-builder.c @@ -0,0 +1,682 @@ +/* json-generator.c - JSON tree builder + * + * This file is part of JSON-GLib + * Copyright (C) 2010 Luca Bruno <lethalman88@gmail.com> + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2.1 of the License, or (at your option) any later version. + * + * This library 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 + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library. If not, see <http://www.gnu.org/licenses/>. + * + * Author: + * Luca Bruno <lethalman88@gmail.com> + */ + +/** + * SECTION:json-builder + * @short_description: Generates JSON trees + * + * #JsonBuilder provides an object for generating a JSON tree. + * You can generate only one tree with one #JsonBuilder instance. + * + * The root of the JSON tree can be either a #JsonObject or a #JsonArray. + * Thus the first call must necessarily be either + * json_builder_begin_object() or json_builder_begin_array(). + * + * For convenience to language bindings, #JsonBuilder returns itself from + * most of functions, making it easy to chain function calls. + */ + +#ifdef HAVE_CONFIG_H +#include "config.h" +#endif + +#include <stdlib.h> +#include <string.h> + +#include "json-types-private.h" + +#include "json-builder.h" + +#define JSON_BUILDER_GET_PRIVATE(obj) \ + (G_TYPE_INSTANCE_GET_PRIVATE ((obj), JSON_TYPE_BUILDER, JsonBuilderPrivate)) + +struct _JsonBuilderPrivate +{ + GQueue *stack; + JsonNode *root; +}; + +typedef enum +{ + JSON_BUILDER_MODE_OBJECT, + JSON_BUILDER_MODE_ARRAY, + JSON_BUILDER_MODE_MEMBER +} JsonBuilderMode; + +typedef struct +{ + JsonBuilderMode mode; + + union + { + JsonObject *object; + JsonArray *array; + } data; + gchar *member_name; +} JsonBuilderState; + +static void +json_builder_state_free (JsonBuilderState *state) +{ + if (G_LIKELY (state)) + { + switch (state->mode) + { + case JSON_BUILDER_MODE_OBJECT: + case JSON_BUILDER_MODE_MEMBER: + json_object_unref (state->data.object); + g_free (state->member_name); + state->data.object = NULL; + state->member_name = NULL; + break; + case JSON_BUILDER_MODE_ARRAY: + json_array_unref (state->data.array); + state->data.array = NULL; + break; + default: + g_assert_not_reached (); + } + + g_slice_free (JsonBuilderState, state); + } +} + +G_DEFINE_TYPE (JsonBuilder, json_builder, G_TYPE_OBJECT); + +static void +json_builder_free_all_state (JsonBuilder *builder) +{ + JsonBuilderState *state; + + while (!g_queue_is_empty (builder->priv->stack)) + { + state = g_queue_pop_head (builder->priv->stack); + json_builder_state_free (state); + } + + if (builder->priv->root) + { + json_node_free (builder->priv->root); + builder->priv->root = NULL; + } +} + +static void +json_builder_finalize (GObject *gobject) +{ + JsonBuilderPrivate *priv = JSON_BUILDER_GET_PRIVATE (gobject); + + json_builder_free_all_state (JSON_BUILDER (gobject)); + + g_queue_free (priv->stack); + priv->stack = NULL; + + G_OBJECT_CLASS (json_builder_parent_class)->finalize (gobject); +} + +static void +json_builder_class_init (JsonBuilderClass *klass) +{ + GObjectClass *gobject_class = G_OBJECT_CLASS (klass); + + g_type_class_add_private (klass, sizeof (JsonBuilderPrivate)); + + gobject_class->finalize = json_builder_finalize; +} + +static void +json_builder_init (JsonBuilder *builder) +{ + JsonBuilderPrivate *priv; + + builder->priv = priv = JSON_BUILDER_GET_PRIVATE (builder); + + priv->stack = g_queue_new (); + priv->root = NULL; +} + +static inline JsonBuilderMode +json_builder_current_mode (JsonBuilder *builder) +{ + JsonBuilderState *state = g_queue_peek_head (builder->priv->stack); + return state->mode; +} + +static inline gboolean +json_builder_is_valid_add_mode (JsonBuilder *builder) +{ + JsonBuilderMode mode = json_builder_current_mode (builder); + return mode == JSON_BUILDER_MODE_MEMBER || mode == JSON_BUILDER_MODE_ARRAY; +} + +/** + * json_builder_new: + * + * Creates a new #JsonBuilder. You can use this object to generate a + * JSON tree and obtain the root #JsonNode<!-- -->s. + * + * Return value: the newly created #JsonBuilder instance + */ +JsonBuilder * +json_builder_new (void) +{ + return g_object_new (JSON_TYPE_BUILDER, NULL); +} + +/** + * json_builder_get_root: + * @builder: a #JsonBuilder + * + * Returns the root of the current constructed tree, if the build is complete + * (ie: all opened objects, object members and arrays are being closed). + * + * Return value: (transfer full): the #JsonNode, or %NULL if the build is not complete. + * Free the returned value with json_node_free(). + */ +JsonNode * +json_builder_get_root (JsonBuilder *builder) +{ + JsonNode *root = NULL; + + g_return_val_if_fail (JSON_IS_BUILDER (builder), NULL); + + if (builder->priv->root) + root = json_node_copy (builder->priv->root); + + return root; +} + +/** + * json_builder_reset: + * @builder: a #JsonBuilder + * + * Resets the state of the @builder back to its initial state. + */ +void +json_builder_reset (JsonBuilder *builder) +{ + g_return_if_fail (JSON_IS_BUILDER (builder)); + + json_builder_free_all_state (builder); +} + +/** + * json_builder_begin_object: + * @builder: a #JsonBuilder + * + * Opens a subobject inside the given @builder. When done adding members to + * the subobject, json_builder_end_object() must be called. + * + * Can be called for first or only if the call is associated to an object member + * or an array element. + * + * Return value: the #JsonBuilder, or %NULL if the call was inconsistent + */ +JsonBuilder * +json_builder_begin_object (JsonBuilder *builder) +{ + JsonObject *object; + JsonBuilderState *state; + JsonBuilderState *cur_state; + + g_return_val_if_fail (JSON_IS_BUILDER (builder), NULL); + g_return_val_if_fail (builder->priv->root == NULL, NULL); + g_return_val_if_fail (g_queue_is_empty (builder->priv->stack) || json_builder_is_valid_add_mode (builder), NULL); + + object = json_object_new (); + cur_state = g_queue_peek_head (builder->priv->stack); + if (cur_state) + { + switch (cur_state->mode) + { + case JSON_BUILDER_MODE_ARRAY: + json_array_add_object_element (cur_state->data.array, json_object_ref (object)); + break; + + case JSON_BUILDER_MODE_MEMBER: + json_object_set_object_member (cur_state->data.object, cur_state->member_name, json_object_ref (object)); + g_free (cur_state->member_name); + cur_state->member_name = NULL; + cur_state->mode = JSON_BUILDER_MODE_OBJECT; + break; + + default: + g_assert_not_reached (); + } + } + + state = g_slice_new (JsonBuilderState); + state->data.object = object; + state->mode = JSON_BUILDER_MODE_OBJECT; + g_queue_push_head (builder->priv->stack, state); + + return builder; +} + +/** + * json_builder_end_object: + * @builder: a #JsonBuilder + * + * Closes the subobject inside the given @builder that was opened by the most + * recent call to json_builder_begin_object(). + * + * Cannot be called after json_builder_set_member_name(). + * + * Return value: the #JsonBuilder, or %NULL if the call was inconsistent + */ +JsonBuilder * +json_builder_end_object (JsonBuilder *builder) +{ + JsonBuilderState *state; + + g_return_val_if_fail (JSON_IS_BUILDER (builder), NULL); + g_return_val_if_fail (!g_queue_is_empty (builder->priv->stack), NULL); + g_return_val_if_fail (json_builder_current_mode (builder) == JSON_BUILDER_MODE_OBJECT, NULL); + + state = g_queue_pop_head (builder->priv->stack); + + if (g_queue_is_empty (builder->priv->stack)) + { + builder->priv->root = json_node_new (JSON_NODE_OBJECT); + json_node_take_object (builder->priv->root, json_object_ref (state->data.object)); + } + + json_builder_state_free (state); + + return builder; +} + +/** + * json_builder_begin_array: + * @builder: a #JsonBuilder + * + * Opens a subarray inside the given @builder. When done adding members to + * the subarray, json_builder_end_array() must be called. + * + * Can be called for first or only if the call is associated to an object member + * or an array element. + * + * Return value: the #JsonBuilder, or %NULL if the call was inconsistent + */ +JsonBuilder * +json_builder_begin_array (JsonBuilder *builder) +{ + JsonArray *array; + JsonBuilderState *state; + JsonBuilderState *cur_state; + + g_return_val_if_fail (JSON_IS_BUILDER (builder), NULL); + g_return_val_if_fail (builder->priv->root == NULL, NULL); + g_return_val_if_fail (g_queue_is_empty (builder->priv->stack) || json_builder_is_valid_add_mode (builder), NULL); + + array = json_array_new (); + cur_state = g_queue_peek_head (builder->priv->stack); + if (cur_state) + { + switch (cur_state->mode) + { + case JSON_BUILDER_MODE_ARRAY: + json_array_add_array_element (cur_state->data.array, json_array_ref (array)); + break; + + case JSON_BUILDER_MODE_MEMBER: + json_object_set_array_member (cur_state->data.object, cur_state->member_name, json_array_ref (array)); + g_free (cur_state->member_name); + cur_state->member_name = NULL; + cur_state->mode = JSON_BUILDER_MODE_OBJECT; + break; + + default: + g_assert_not_reached (); + } + } + + state = g_slice_new (JsonBuilderState); + state->data.array = array; + state->mode = JSON_BUILDER_MODE_ARRAY; + g_queue_push_head (builder->priv->stack, state); + + return builder; +} + +/** + * json_builder_end_array: + * @builder: a #JsonBuilder + * + * Closes the subarray inside the given @builder that was opened by the most + * recent call to json_builder_begin_array(). + * + * Cannot be called after json_builder_set_member_name(). + * + * Return value: the #JsonBuilder, or %NULL if the call was inconsistent + */ +JsonBuilder * +json_builder_end_array (JsonBuilder *builder) +{ + JsonBuilderState *state; + + g_return_val_if_fail (JSON_IS_BUILDER (builder), NULL); + g_return_val_if_fail (!g_queue_is_empty (builder->priv->stack), NULL); + g_return_val_if_fail (json_builder_current_mode (builder) == JSON_BUILDER_MODE_ARRAY, NULL); + + state = g_queue_pop_head (builder->priv->stack); + + if (g_queue_is_empty (builder->priv->stack)) + { + builder->priv->root = json_node_new (JSON_NODE_ARRAY); + json_node_take_array (builder->priv->root, json_array_ref (state->data.array)); + } + + json_builder_state_free (state); + + return builder; +} + +/** + * json_builder_set_member_name: + * @builder: a #JsonBuilder + * @member_name: the name of the member + * + * Set the name of the next member in an object. The next call must add a value, + * open an object or an array. + * + * Can be called only if the call is associated to an object. + * + * Return value: the #JsonBuilder, or %NULL if the call was inconsistent + */ +JsonBuilder * +json_builder_set_member_name (JsonBuilder *builder, const gchar *member_name) +{ + JsonBuilderState *state; + + g_return_val_if_fail (JSON_IS_BUILDER (builder), NULL); + g_return_val_if_fail (member_name != NULL, NULL); + g_return_val_if_fail (!g_queue_is_empty (builder->priv->stack), NULL); + g_return_val_if_fail (json_builder_current_mode (builder) == JSON_BUILDER_MODE_OBJECT, NULL); + + state = g_queue_peek_head (builder->priv->stack); + state->member_name = g_strdup (member_name); + state->mode = JSON_BUILDER_MODE_MEMBER; + + return builder; +} + +/** + * json_builder_add_value: + * @builder: a #JsonBuilder + * @node: the value of the member or element + * + * If called after json_builder_set_member_name(), sets @node as member of the + * most recent opened object, otherwise @node is added as element of the most + * recent opened array. + * + * Return value: the #JsonBuilder, or %NULL if the call was inconsistent + */ +JsonBuilder * +json_builder_add_value (JsonBuilder *builder, JsonNode *node) +{ + JsonBuilderState *state; + + g_return_val_if_fail (JSON_IS_BUILDER (builder), NULL); + g_return_val_if_fail (node != NULL, NULL); + g_return_val_if_fail (!g_queue_is_empty (builder->priv->stack), NULL); + g_return_val_if_fail (json_builder_is_valid_add_mode (builder), NULL); + + state = g_queue_peek_head (builder->priv->stack); + switch (state->mode) + { + case JSON_BUILDER_MODE_MEMBER: + json_object_set_member (state->data.object, state->member_name, node); + g_free (state->member_name); + state->member_name = NULL; + state->mode = JSON_BUILDER_MODE_OBJECT; + break; + + case JSON_BUILDER_MODE_ARRAY: + json_array_add_element (state->data.array, node); + break; + + default: + g_assert_not_reached (); + } + + return builder; +} + +/** + * json_builder_add_int_value: + * @builder: a #JsonBuilder + * @value: the value of the member or element + * + * If called after json_builder_set_member_name(), sets @value as member of the + * most recent opened object, otherwise @value is added as element of the most + * recent opened array. + * + * See also: json_builder_add_value() + * + * Return value: the #JsonBuilder, or %NULL if the call was inconsistent + */ +JsonBuilder * +json_builder_add_int_value (JsonBuilder *builder, gint64 value) +{ + JsonBuilderState *state; + + g_return_val_if_fail (JSON_IS_BUILDER (builder), NULL); + g_return_val_if_fail (!g_queue_is_empty (builder->priv->stack), NULL); + g_return_val_if_fail (json_builder_is_valid_add_mode (builder), NULL); + + state = g_queue_peek_head (builder->priv->stack); + switch (state->mode) + { + case JSON_BUILDER_MODE_MEMBER: + json_object_set_int_member (state->data.object, state->member_name, value); + g_free (state->member_name); + state->member_name = NULL; + state->mode = JSON_BUILDER_MODE_OBJECT; + break; + + case JSON_BUILDER_MODE_ARRAY: + json_array_add_int_element (state->data.array, value); + break; + + default: + g_assert_not_reached (); + } + + return builder; +} + +/** + * json_builder_add_double_value: + * @builder: a #JsonBuilder + * @value: the value of the member or element + * + * If called after json_builder_set_member_name(), sets @value as member of the + * most recent opened object, otherwise @value is added as element of the most + * recent opened array. + * + * See also: json_builder_add_value() + * + * Return value: the #JsonBuilder, or %NULL if the call was inconsistent + */ +JsonBuilder * +json_builder_add_double_value (JsonBuilder *builder, gdouble value) +{ + JsonBuilderState *state; + + g_return_val_if_fail (JSON_IS_BUILDER (builder), NULL); + g_return_val_if_fail (!g_queue_is_empty (builder->priv->stack), NULL); + g_return_val_if_fail (json_builder_is_valid_add_mode (builder), NULL); + + state = g_queue_peek_head (builder->priv->stack); + + switch (state->mode) + { + case JSON_BUILDER_MODE_MEMBER: + json_object_set_double_member (state->data.object, state->member_name, value); + g_free (state->member_name); + state->member_name = NULL; + state->mode = JSON_BUILDER_MODE_OBJECT; + break; + + case JSON_BUILDER_MODE_ARRAY: + json_array_add_double_element (state->data.array, value); + break; + + default: + g_assert_not_reached (); + } + + return builder; +} + +/** + * json_builder_add_boolean_value: + * @builder: a #JsonBuilder + * @value: the value of the member or element + * + * If called after json_builder_set_member_name(), sets @value as member of the + * most recent opened object, otherwise @value is added as element of the most + * recent opened array. + * + * See also: json_builder_add_value() + * + * Return value: the #JsonBuilder, or %NULL if the call was inconsistent + */ +JsonBuilder * +json_builder_add_boolean_value (JsonBuilder *builder, gboolean value) +{ + JsonBuilderState *state; + + g_return_val_if_fail (JSON_IS_BUILDER (builder), NULL); + g_return_val_if_fail (!g_queue_is_empty (builder->priv->stack), NULL); + g_return_val_if_fail (json_builder_is_valid_add_mode (builder), NULL); + + state = g_queue_peek_head (builder->priv->stack); + + switch (state->mode) + { + case JSON_BUILDER_MODE_MEMBER: + json_object_set_boolean_member (state->data.object, state->member_name, value); + g_free (state->member_name); + state->member_name = NULL; + state->mode = JSON_BUILDER_MODE_OBJECT; + break; + + case JSON_BUILDER_MODE_ARRAY: + json_array_add_boolean_element (state->data.array, value); + break; + + default: + g_assert_not_reached (); + } + + return builder; +} + +/** + * json_builder_add_string_value: + * @builder: a #JsonBuilder + * @value: the value of the member or element + * + * If called after json_builder_set_member_name(), sets @value as member of the + * most recent opened object, otherwise @value is added as element of the most + * recent opened array. + * + * See also: json_builder_add_value() + * + * Return value: the #JsonBuilder, or %NULL if the call was inconsistent + */ +JsonBuilder * +json_builder_add_string_value (JsonBuilder *builder, const gchar *value) +{ + JsonBuilderState *state; + + g_return_val_if_fail (JSON_IS_BUILDER (builder), NULL); + g_return_val_if_fail (!g_queue_is_empty (builder->priv->stack), NULL); + g_return_val_if_fail (json_builder_is_valid_add_mode (builder), NULL); + + state = g_queue_peek_head (builder->priv->stack); + + switch (state->mode) + { + case JSON_BUILDER_MODE_MEMBER: + json_object_set_string_member (state->data.object, state->member_name, value); + g_free (state->member_name); + state->member_name = NULL; + state->mode = JSON_BUILDER_MODE_OBJECT; + break; + + case JSON_BUILDER_MODE_ARRAY: + json_array_add_string_element (state->data.array, value); + break; + + default: + g_assert_not_reached (); + } + + return builder; +} + +/** + * json_builder_add_null_value: + * @builder: a #JsonBuilder + * @value: the value of the member or element + * + * If called after json_builder_set_member_name(), sets null as member of the + * most recent opened object, otherwise null is added as element of the most + * recent opened array. + * + * See also: json_builder_add_value() + * + * Return value: the #JsonBuilder, or %NULL if the call was inconsistent + */ +JsonBuilder * +json_builder_add_null_value (JsonBuilder *builder) +{ + JsonBuilderState *state; + + g_return_val_if_fail (JSON_IS_BUILDER (builder), NULL); + g_return_val_if_fail (!g_queue_is_empty (builder->priv->stack), NULL); + g_return_val_if_fail (json_builder_is_valid_add_mode (builder), NULL); + + state = g_queue_peek_head (builder->priv->stack); + + switch (state->mode) + { + case JSON_BUILDER_MODE_MEMBER: + json_object_set_null_member (state->data.object, state->member_name); + g_free (state->member_name); + state->member_name = NULL; + state->mode = JSON_BUILDER_MODE_OBJECT; + break; + + case JSON_BUILDER_MODE_ARRAY: + json_array_add_null_element (state->data.array); + break; + + default: + g_assert_not_reached (); + } + + return builder; +} |