Add internal JSON encoding and decoding support

Add JSON support based loosely on Heimdal's heimbase code.

1 files changed, 192 insertions, 0 deletions

diff --git a/src/include/k5-json.h b/src/include/k5-json.h
new file mode 100644
index 0000000000..fb9a3afe6c
--- /dev/null
+++ b/src/include/k5-json.h
@@ -0,0 +1,192 @@
+/* -*- mode: c; c-basic-offset: 4; indent-tabs-mode: nil -*- */
+/* include/k5-json.h - JSON declarations */
+/*
+ * Copyright (c) 2010 Kungliga Tekniska Högskolan
+ * (Royal Institute of Technology, Stockholm, Sweden).
+ * All rights reserved.
+ *
+ * Portions Copyright (c) 2010 Apple Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * 3. Neither the name of the Institute nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+/*
+ * Copyright (C) 2012 by the Massachusetts Institute of Technology.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * * Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ *
+ * * Redistributions in binary form must reproduce the above copyright
+ *   notice, this list of conditions and the following disclaimer in
+ *   the documentation and/or other materials provided with the
+ *   distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
+ * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef K5_JSON_H
+#define K5_JSON_H
+
+#include <stddef.h>
+
+#define K5_JSON_TID_NUMBER 0
+#define K5_JSON_TID_NULL 1
+#define K5_JSON_TID_BOOL 2
+#define K5_JSON_TID_MEMORY 128
+#define K5_JSON_TID_ARRAY 129
+#define K5_JSON_TID_OBJECT 130
+#define K5_JSON_TID_STRING 131
+
+/*
+ * The k5_json_value C type can represent any kind of JSON value.  It has no
+ * static type safety since it is represented using a void pointer, so be
+ * careful with it.  Its type can be checked dynamically with k5_json_get_tid()
+ * and the above constants.
+ */
+typedef void *k5_json_value;
+typedef unsigned int k5_json_tid;
+
+k5_json_tid k5_json_get_tid(k5_json_value val);
+
+/*
+ * k5_json_value objects are reference-counted.  These functions increment and
+ * decrement the refcount, possibly freeing the value.  k5_json_retain returns
+ * its argument and always succeeds.  Both functions gracefully accept NULL.
+ */
+void *k5_json_retain(k5_json_value val);
+void k5_json_release(k5_json_value val);
+
+/*
+ * Unless otherwise specified, the following functions return NULL on error
+ * (generally only if out of memory) if they return a pointer type, or 0 on
+ * success and -1 on failure if they return int.
+ */
+
+/*
+ * Null
+ */
+
+typedef struct k5_json_null_st *k5_json_null;
+
+k5_json_null k5_json_null_create(void);
+
+/*
+ * Boolean
+ */
+
+typedef struct k5_json_bool_st *k5_json_bool;
+
+k5_json_bool k5_json_bool_create(int truth);
+int k5_json_bool_value(k5_json_bool bval);
+
+/*
+ * Array
+ */
+
+typedef struct k5_json_array_st *k5_json_array;
+
+k5_json_array k5_json_array_create(void);
+size_t k5_json_array_length(k5_json_array array);
+
+/* Both of these functions increment the reference count on val. */
+int k5_json_array_add(k5_json_array array, k5_json_value val);
+void k5_json_array_set(k5_json_array array, size_t idx, k5_json_value val);
+
+/* Get an alias to the idx-th element of array, without incrementing the
+ * reference count.  The caller must check idx against the array length. */
+k5_json_value k5_json_array_get(k5_json_array array, size_t idx);
+
+/*
+ * Object
+ */
+
+typedef struct k5_json_object_st *k5_json_object;
+typedef void (*k5_json_object_iterator_fn)(void *arg, const char *key,
+                                           k5_json_value val);
+
+k5_json_object k5_json_object_create(void);
+void k5_json_object_iterate(k5_json_object obj,
+                            k5_json_object_iterator_fn func, void *arg);
+
+
+/* Store val into object at key, incrementing val's reference count. */
+int k5_json_object_set(k5_json_object obj, const char *key, k5_json_value val);
+
+/* Get an alias to the object's value for key, without incrementing the
+ * reference count.  Returns NULL if there is no value for key. */
+k5_json_value k5_json_object_get(k5_json_object obj, const char *key);
+
+/*
+ * String
+ */
+
+typedef struct k5_json_string_st *k5_json_string;
+
+k5_json_string k5_json_string_create(const char *string);
+k5_json_string k5_json_string_create_len(const void *data, size_t len);
+const char *k5_json_string_utf8(k5_json_string string);
+
+/* Create a base64 string value from binary data. */
+k5_json_string k5_json_string_create_base64(const void *data, size_t len);
+
+/* Decode a base64 string.  Returns NULL and *len_out == 0 if out of memory,
+ * NULL and *len == SIZE_MAX if string's contents aren't valid base64. */
+void *k5_json_string_unbase64(k5_json_string string, size_t *len_out);
+
+/*
+ * Number
+ */
+
+typedef struct k5_json_number_st *k5_json_number;
+
+k5_json_number k5_json_number_create(long long number);
+long long k5_json_number_value(k5_json_number number);
+
+/*
+ * JSON encoding and decoding
+ */
+
+char *k5_json_encode(k5_json_value val);
+k5_json_value k5_json_decode(const char *str);
+
+#endif /* K5_JSON_H */