JSON: Add encoding/decoding

CMakeLists.txt

@@ -219,6 +219,9 @@ if(UA_ENABLE_PUBSUB_INFORMATIONMODEL)
     endif()
 endif()
 
+option(UA_ENABLE_JSON_ENCODING "Enable Json encoding (EXPERIMENTAL)" OFF)
+mark_as_advanced(UA_ENABLE_JSON_ENCODING)
+
 option(UA_ENABLE_STATUSCODE_DESCRIPTIONS "Enable conversion of StatusCode to human-readable error message" ON)
 mark_as_advanced(UA_ENABLE_STATUSCODE_DESCRIPTIONS)
 
@@ -620,6 +623,24 @@ if(UA_ENABLE_PUBSUB)
     endif()
 endif()
 
+if(UA_ENABLE_JSON_ENCODING)
+    list(APPEND internal_headers ${PROJECT_SOURCE_DIR}/deps/jsmn/jsmn.h
+                                 ${PROJECT_SOURCE_DIR}/deps/string_escape.h
+                                 ${PROJECT_SOURCE_DIR}/deps/itoa.h
+                                 ${PROJECT_SOURCE_DIR}/deps/atoi.h
+                                 ${PROJECT_SOURCE_DIR}/src/ua_types_encoding_json.h)
+    list(APPEND lib_sources ${PROJECT_SOURCE_DIR}/deps/jsmn/jsmn.c
+                            ${PROJECT_SOURCE_DIR}/deps/string_escape.c
+                            ${PROJECT_SOURCE_DIR}/deps/itoa.c
+                            ${PROJECT_SOURCE_DIR}/deps/atoi.c
+                            ${PROJECT_SOURCE_DIR}/src/ua_types_encoding_json.c)
+endif()
+
+if(UA_ENABLE_CUSTOM_LIBC)
+     list(APPEND lib_sources ${PROJECT_SOURCE_DIR}/deps/musl/floatscan.c
+                             ${PROJECT_SOURCE_DIR}/deps/musl/vfprintf.c)
+endif()
+
 if(UA_ENABLE_SUBSCRIPTIONS)
     list(APPEND lib_sources ${PROJECT_SOURCE_DIR}/src/server/ua_subscription.c
                             ${PROJECT_SOURCE_DIR}/src/server/ua_subscription_monitoreditem.c
@@ -1108,3 +1129,4 @@ set_target_properties(open62541-generator-namespace PROPERTIES FOLDER "open62541
 set_target_properties(open62541-generator-statuscode PROPERTIES FOLDER "open62541/generators")
 set_target_properties(open62541-generator-transport PROPERTIES FOLDER "open62541/generators")
 set_target_properties(open62541-generator-types PROPERTIES FOLDER "open62541/generators")
+

src/ua_types_encoding_json.h

@@ -0,0 +1,142 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ *    Copyright 2014-2017 (c) Fraunhofer IOSB (Author: Julius Pfrommer)
+ *    Copyright 2018 (c) Fraunhofer IOSB (Author: Lukas Meling)
+ */
+
+#ifndef UA_TYPES_ENCODING_JSON_H_
+#define UA_TYPES_ENCODING_JSON_H_
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include "ua_util_internal.h"
+#include "ua_types_encoding_binary.h"
+#include "ua_types_encoding_json.h"
+#include "ua_types.h"
+#include "../deps/jsmn/jsmn.h"
+#include "assert.h"
+ 
+#define TOKENCOUNT 1000
+    
+size_t
+UA_calcSizeJson(const void *src, const UA_DataType *type,
+                UA_String *namespaces, size_t namespaceSize,
+                UA_String *serverUris, size_t serverUriSize,
+                UA_Boolean useReversible) UA_FUNC_ATTR_WARN_UNUSED_RESULT;
+
+
+UA_StatusCode
+UA_encodeJson(const void *src, const UA_DataType *type,
+              uint8_t **bufPos, const uint8_t **bufEnd,
+              UA_String *namespaces, size_t namespaceSize,
+              UA_String *serverUris, size_t serverUriSize,
+              UA_Boolean useReversible) UA_FUNC_ATTR_WARN_UNUSED_RESULT;
+
+UA_StatusCode
+UA_decodeJson(const UA_ByteString *src, void *dst,
+              const UA_DataType *type) UA_FUNC_ATTR_WARN_UNUSED_RESULT;
+
+/* Interal Definitions
+ *
+ * For future by the PubSub encoding */
+
+#define UA_JSON_ENCODING_MAX_RECURSION 100
+typedef struct {
+    uint8_t *pos;
+    const uint8_t *end;
+
+    size_t namespacesSize;
+    UA_String *namespaces;
+    
+    size_t serverUrisSize;
+    UA_String *serverUris;
+    
+    uint16_t depth; /* How often did we en-/decoding recurse? */
+    UA_Boolean useReversible;
+    UA_Boolean commaNeeded[UA_JSON_ENCODING_MAX_RECURSION];
+} CtxJson;
+
+UA_StatusCode writeJsonObjStart(CtxJson *ctx);
+UA_StatusCode writeJsonObjElm(CtxJson *ctx, UA_String *key,
+                              const void *value, const UA_DataType *type);
+UA_StatusCode writeJsonObjEnd(CtxJson *ctx);
+
+UA_StatusCode writeJsonArrStart(CtxJson *ctx);
+UA_StatusCode writeJsonArrElm(CtxJson *ctx, const void *value,
+                              const UA_DataType *type);
+UA_StatusCode writeJsonArrEnd(CtxJson *ctx);
+
+UA_StatusCode writeJsonKey(CtxJson *ctx, const char* key);
+UA_StatusCode writeJsonCommaIfNeeded(CtxJson *ctx);
+UA_StatusCode writeJsonNull(CtxJson *ctx);
+
+/* The encoding length is returned in ctx->pos */
+UA_StatusCode calcJsonObjStart(CtxJson *ctx);
+UA_StatusCode calcJsonObjElm(CtxJson *ctx, UA_String *key,
+                             const void *value, const UA_DataType *type);
+UA_StatusCode calcJsonObjEnd(CtxJson *ctx);
+
+UA_StatusCode calcJsonArrStart(CtxJson *ctx);
+UA_StatusCode calcJsonArrElm(CtxJson *ctx, const void *value,
+                             const UA_DataType *type);
+UA_StatusCode calcJsonArrEnd(CtxJson *ctx);
+
+UA_StatusCode calcJsonKey(CtxJson *ctx, const char* key);
+UA_StatusCode calcJsonCommaIfNeeded(CtxJson *ctx);
+UA_StatusCode calcJsonNull(CtxJson *ctx);
+
+typedef struct {
+    jsmntok_t *tokenArray;
+    UA_Int32 tokenCount;
+    UA_UInt16 *index;
+} ParseCtx;
+
+typedef UA_StatusCode
+(*encodeJsonSignature)(const void *src, const UA_DataType *type, CtxJson *ctx);
+
+typedef UA_StatusCode
+(*calcSizeJsonSignature)(const void *src, const UA_DataType *type, CtxJson *ctx);
+
+typedef UA_StatusCode
+(*decodeJsonSignature)(void *dst, const UA_DataType *type,
+                       CtxJson *ctx, ParseCtx *parseCtx,
+                       UA_Boolean moveToken);
+
+/* Map for decoding a Json Object. An array of this is passed to the
+ * decodeFields function. If the key "fieldName" is found in the json object
+ * (mark as found and) decode the value with the "function" and write result
+ * into "fieldPointer" (destination). */
+typedef struct {
+    const char * fieldName;
+    void * fieldPointer;
+    decodeJsonSignature function;
+    UA_Boolean found;
+} DecodeEntry;
+
+UA_StatusCode
+decodeFields(CtxJson *ctx, ParseCtx *parseCtx,
+             DecodeEntry *entries, size_t entryCount,
+             const UA_DataType *type);
+
+UA_StatusCode
+decodeJsonInternal(void *dst, const UA_DataType *type,
+                   CtxJson *ctx, ParseCtx *parseCtx, UA_Boolean moveToken);
+
+/* workaround: TODO generate functions for UA_xxx_decodeJson */
+decodeJsonSignature getDecodeSignature(u8 index);
+UA_StatusCode lookAheadForKey(const char* search, CtxJson *ctx, ParseCtx *parseCtx,
+                              size_t *resultIndex);
+jsmntype_t getJsmnType(const ParseCtx *parseCtx);
+UA_StatusCode tokenize(ParseCtx *parseCtx, CtxJson *ctx,
+                       const UA_ByteString *src, UA_UInt16 *tokenIndex);
+UA_Boolean isJsonNull(const CtxJson *ctx, const ParseCtx *parseCtx);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* UA_TYPES_ENCODING_JSON_H_ */