json: new module for parsing and generating JSON

[ccan] / ccan / json / json.h

diff --git a/ccan/json/json.h b/ccan/json/json.h
new file mode 100644 (file)
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--- /dev/null
+++ b/ccan/json/json.h
@@ -0,0 +1,117 @@
+/*
+  Copyright (C) 2011 Joseph A. Adams (joeyadams3.14159@gmail.com)
+  All rights reserved.
+
+  Permission is hereby granted, free of charge, to any person obtaining a copy
+  of this software and associated documentation files (the "Software"), to deal
+  in the Software without restriction, including without limitation the rights
+  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+  copies of the Software, and to permit persons to whom the Software is
+  furnished to do so, subject to the following conditions:
+
+  The above copyright notice and this permission notice shall be included in
+  all copies or substantial portions of the Software.
+
+  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+  THE SOFTWARE.
+*/
+
+#ifndef CCAN_JSON_H
+#define CCAN_JSON_H
+
+#include <stdbool.h>
+#include <stddef.h>
+
+typedef enum {
+       JSON_NULL,
+       JSON_BOOL,
+       JSON_STRING,
+       JSON_NUMBER,
+       JSON_ARRAY,
+       JSON_OBJECT,
+} JsonTag;
+
+typedef struct JsonNode JsonNode;
+
+struct JsonNode
+{
+       /* only if parent is an object or array (NULL otherwise) */
+       JsonNode *parent;
+       JsonNode *prev, *next;
+       
+       /* only if parent is an object (NULL otherwise) */
+       char *key; /* Must be valid UTF-8. */
+       
+       JsonTag tag;
+       union {
+               /* JSON_BOOL */
+               bool bool_;
+               
+               /* JSON_STRING */
+               char *string_; /* Must be valid UTF-8. */
+               
+               /* JSON_NUMBER */
+               double number_;
+               
+               /* JSON_ARRAY */
+               /* JSON_OBJECT */
+               struct {
+                       JsonNode *head, *tail;
+               } children;
+       };
+};
+
+/*** Encoding, decoding, and validation ***/
+
+JsonNode   *json_decode         (const char *json);
+char       *json_encode         (const JsonNode *node);
+char       *json_encode_string  (const char *str);
+char       *json_stringify      (const JsonNode *node, const char *space);
+void        json_delete         (JsonNode *node);
+
+bool        json_validate       (const char *json);
+
+/*** Lookup and traversal ***/
+
+JsonNode   *json_find_element   (JsonNode *array, int index);
+JsonNode   *json_find_member    (JsonNode *object, const char *key);
+
+JsonNode   *json_first_child    (const JsonNode *node);
+
+#define json_foreach(i, object_or_array)            \
+       for ((i) = json_first_child(object_or_array);   \
+                (i) != NULL;                               \
+                (i) = (i)->next)
+
+/*** Construction and manipulation ***/
+
+JsonNode *json_mknull(void);
+JsonNode *json_mkbool(bool b);
+JsonNode *json_mkstring(const char *s);
+JsonNode *json_mknumber(double n);
+JsonNode *json_mkarray(void);
+JsonNode *json_mkobject(void);
+
+void json_append_element(JsonNode *array, JsonNode *element);
+void json_prepend_element(JsonNode *array, JsonNode *element);
+void json_append_member(JsonNode *object, const char *key, JsonNode *value);
+void json_prepend_member(JsonNode *object, const char *key, JsonNode *value);
+
+void json_remove_from_parent(JsonNode *node);
+
+/*** Debugging ***/
+
+/*
+ * Look for structure and encoding problems in a JsonNode or its descendents.
+ *
+ * If a problem is detected, return false, writing a description of the problem
+ * to errmsg (unless errmsg is NULL).
+ */
+bool json_check(const JsonNode *node, char errmsg[256]);
+
+#endif