[edk2-devel] [PATCH v2 2/3] RedfishPkg/library: EDK2 port of jansson library

Abner Chang abner.chang at hpe.com
Tue Dec 1 02:25:43 UTC 2020


edk2 JsonLib which is the edk2 port of open source
jansson library.
(https://github.com/akheron/jansson)

Signed-off-by: Abner Chang <abner.chang at hpe.com>

Cc: Andrew Fish <afish at apple.com>
Cc: Laszlo Ersek <lersek at redhat.com>
Cc: Leif Lindholm <leif at nuviainc.com>
Cc: Michael D Kinney <michael.d.kinney at intel.com>
Cc: Nickle Wang <nickle.wang at hpe.com>
Cc: Peter O'Hanley <peter.ohanley at hpe.com>
---
 .../Include/Library/JanssonJsonLibMapping.h   |   63 +
 RedfishPkg/Include/Library/JsonLib.h          |  767 ++++++++++++
 .../Library/JsonLib/JanssonCrtLibSupport.c    |  705 +++++++++++
 .../Library/JsonLib/JanssonCrtLibSupport.h    |  198 +++
 RedfishPkg/Library/JsonLib/JsonLib.c          |  960 ++++++++++++++
 RedfishPkg/Library/JsonLib/JsonLib.inf        |  103 ++
 RedfishPkg/Library/JsonLib/JsonUtilities.c    |  417 +++++++
 RedfishPkg/Library/JsonLib/JsonUtilities.h    |   69 +
 RedfishPkg/Library/JsonLib/Readme.txt         |   40 +
 RedfishPkg/Library/JsonLib/assert.h           |   16 +
 RedfishPkg/Library/JsonLib/errno.h            |   16 +
 RedfishPkg/Library/JsonLib/jansson_config.h   |   60 +
 .../Library/JsonLib/jansson_private_config.h  |   19 +
 RedfishPkg/Library/JsonLib/limits.h           |   16 +
 RedfishPkg/Library/JsonLib/load.c             | 1111 +++++++++++++++++
 RedfishPkg/Library/JsonLib/math.h             |   16 +
 RedfishPkg/Library/JsonLib/stdarg.h           |   15 +
 RedfishPkg/Library/JsonLib/stddef.h           |   16 +
 RedfishPkg/Library/JsonLib/stdio.h            |   15 +
 RedfishPkg/Library/JsonLib/stdlib.h           |   16 +
 RedfishPkg/Library/JsonLib/string.h           |   16 +
 RedfishPkg/Library/JsonLib/sys/time.h         |   15 +
 RedfishPkg/Library/JsonLib/sys/types.h        |   15 +
 RedfishPkg/Library/JsonLib/time.h             |   15 +
 RedfishPkg/RedfishPkg.ci.yaml                 |   33 +-
 25 files changed, 4731 insertions(+), 1 deletion(-)
 create mode 100644 RedfishPkg/Include/Library/JanssonJsonLibMapping.h
 create mode 100644 RedfishPkg/Include/Library/JsonLib.h
 create mode 100644 RedfishPkg/Library/JsonLib/JanssonCrtLibSupport.c
 create mode 100644 RedfishPkg/Library/JsonLib/JanssonCrtLibSupport.h
 create mode 100644 RedfishPkg/Library/JsonLib/JsonLib.c
 create mode 100644 RedfishPkg/Library/JsonLib/JsonLib.inf
 create mode 100644 RedfishPkg/Library/JsonLib/JsonUtilities.c
 create mode 100644 RedfishPkg/Library/JsonLib/JsonUtilities.h
 create mode 100644 RedfishPkg/Library/JsonLib/Readme.txt
 create mode 100644 RedfishPkg/Library/JsonLib/assert.h
 create mode 100644 RedfishPkg/Library/JsonLib/errno.h
 create mode 100644 RedfishPkg/Library/JsonLib/jansson_config.h
 create mode 100644 RedfishPkg/Library/JsonLib/jansson_private_config.h
 create mode 100644 RedfishPkg/Library/JsonLib/limits.h
 create mode 100644 RedfishPkg/Library/JsonLib/load.c
 create mode 100644 RedfishPkg/Library/JsonLib/math.h
 create mode 100644 RedfishPkg/Library/JsonLib/stdarg.h
 create mode 100644 RedfishPkg/Library/JsonLib/stddef.h
 create mode 100644 RedfishPkg/Library/JsonLib/stdio.h
 create mode 100644 RedfishPkg/Library/JsonLib/stdlib.h
 create mode 100644 RedfishPkg/Library/JsonLib/string.h
 create mode 100644 RedfishPkg/Library/JsonLib/sys/time.h
 create mode 100644 RedfishPkg/Library/JsonLib/sys/types.h
 create mode 100644 RedfishPkg/Library/JsonLib/time.h

diff --git a/RedfishPkg/Include/Library/JanssonJsonLibMapping.h b/RedfishPkg/Include/Library/JanssonJsonLibMapping.h
new file mode 100644
index 0000000000..80452d6663
--- /dev/null
+++ b/RedfishPkg/Include/Library/JanssonJsonLibMapping.h
@@ -0,0 +1,63 @@
+/** @file
+  This is the wrapper to map funcitons and definitions used in
+  native jannson applications to edk2 JsonLib. This avoids the
+  modifications on native jannson applications to be built under
+  edk2 environment.
+
+ (C) Copyright 2020 Hewlett Packard Enterprise Development LP<BR>
+
+    SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#ifndef LIBREDFISH_JSON_SUPPORT_H_
+#define LIBREDFISH_JSON_SUPPORT_H_
+
+#include <Library/JsonLib.h>
+
+typedef EDKII_JSON_VALUE   json_t;
+typedef EDKII_JSON_INT_T   json_int_t;
+typedef EDKII_JSON_TYPE    json_type;
+
+///
+/// JSON type mapping
+///
+#define JSON_OBJECT    EdkiiJsonTypeObject
+#define JSON_ARRAY     EdkiiJsonTypeArray
+#define JSON_STRING    EdkiiJsonTypeString
+#define JSON_INTEGER   EdkiiJsonTypeInteger
+#define JSON_REAL      EdkiiJsonTypeReal
+#define JSON_TRUE      EdkiiJsonTypeTrue
+#define JSON_FALSE     EdkiiJsonTypeFalse
+#define JSON_NULL      EdkiiJsonTypeNull
+
+#define JSON_INDENT(n) EDKII_JSON_INDENT(n)
+
+///
+/// JSON function mapping
+///
+#define json_object_get(JsonObj,key)             JsonObjectGetValue(JsonObj,key)
+#define json_is_object(JsonValue)                JsonValueIsObject(JsonValue)
+#define json_is_array(JsonValue)                 JsonValueIsArray(JsonValue)
+#define json_is_string(JsonValue)                JsonValueIsString(JsonValue)
+#define json_integer(JsonValue)                  JsonValueInitNumber(JsonValue)
+#define json_object_set(JsonObj,Key,JsonValue)   JsonObjectSetValue(JsonObj,Key,JsonValue)
+#define json_object()                            JsonValueInitObject()
+#define json_object_size(JsonObject)             JsonObjectSize(JsonObject)
+#define json_array_get(JsonArray,Index)          JsonArrayGetValue(JsonArray,Index)
+#define json_array_append(JsonArray,JsonValue)   JsonArrayAppendValue(JsonArray,JsonValue)
+#define json_dumps(JsonValue,Flags)              JsonDumpString(JsonValue,Flags)
+#define json_string_value(JsonValue)             JsonValueGetString(JsonValue)
+#define json_array_size(JsonArray)               JsonArrayCount(JsonArray)
+#define json_array()                             JsonValueInitArray()
+#define json_loadb(Buffer,BufferLen,Flags,Error) JsonLoadBuffer(Buffer,BufferLen,Flags,Error)
+#define json_decref(JsonValue)                   JsonDecreaseReference(JsonValue)
+#define json_incref(JsonValue)                   JsonIncreaseReference(JsonValue)
+#define json_string(AsciiString)                 JsonValueInitAsciiString(AsciiString)
+#define json_object_iter(JsonValue)              JsonObjectIterator(JsonValue)
+#define json_object_iter_value(Iterator)         JsonObjectIteratorValue(Iterator)
+#define json_object_iter_next(JsonValue,Iterator) JsonObjectIteratorNext(JsonValue,Iterator)
+#define json_integer_value(JsonValue)            JsonValueGetNumber(JsonValue)
+#define json_get_type(JsonValue)                 JsonGetType(JsonValue)
+
+#endif
diff --git a/RedfishPkg/Include/Library/JsonLib.h b/RedfishPkg/Include/Library/JsonLib.h
new file mode 100644
index 0000000000..adadcbf33f
--- /dev/null
+++ b/RedfishPkg/Include/Library/JsonLib.h
@@ -0,0 +1,767 @@
+/** @file
+  APIs for JSON operations.
+
+  Copyright (c) 2019, Intel Corporation. All rights reserved.<BR>
+ (C) Copyright 2020 Hewlett Packard Enterprise Development LP<BR>
+
+    SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+#ifndef JSON_LIB_H_
+#define JSON_LIB_H_
+
+#include <Uefi.h>
+
+#include <Library/BaseMemoryLib.h>
+#include <Library/MemoryAllocationLib.h>
+
+typedef    VOID*    EDKII_JSON_VALUE;
+typedef    VOID*    EDKII_JSON_ARRAY;
+typedef    VOID*    EDKII_JSON_OBJECT;
+
+///
+/// Map to json_int_t in jansson.h
+///
+typedef long long   EDKII_JSON_INT_T;  // #JSON_INTEGER_IS_LONG_LONG is set to 1
+                                       // in jansson_Config.h
+
+///
+///  Map to the definitions in jansson.h
+///
+#define EDKII_JSON_MAX_INDENT        0x1f
+#define EDKII_JSON_INDENT(n)         ((n)&EDKII_JSON_MAX_INDENT)
+#define EDKII_JSON_COMPACT           0x20
+#define EDKII_JSON_ENSURE_ASCII      0x40
+#define EDKII_JSON_SORT_KEYS         0x80
+#define EDKII_JSON_PRESERVE_ORDER    0x100
+#define EDKII_JSON_ENCODE_ANY        0x200
+#define EDKII_JSON_ESCAPE_SLASH      0x400
+#define EDKII_JSON_REAL_PRECISION(n) (((n)&0x1F) << 11)
+#define EDKII_JSON_EMBED             0x10000
+
+#define EDKII_JSON_ARRAY_FOREACH(Array, Index, Value) \
+  for(Index = 0; \
+    Index < JsonArrayCount(Array) && (Value = JsonArrayGetValue(Array, Index)); \
+    Index++)
+
+///
+///  Map to the json_error_t in jansson.h
+///
+#define EDKII_JSON_ERROR_TEXT_LENGTH   160
+#define EDKII_JSON_ERROR_SOURCE_LENGTH 80
+typedef struct {
+    INTN    Line;
+    INTN    Column;
+    INTN    Position;
+    CHAR8   Source [EDKII_JSON_ERROR_SOURCE_LENGTH];
+    CHAR8   Text [EDKII_JSON_ERROR_TEXT_LENGTH];
+} EDKII_JSON_ERROR;
+
+///
+///  Map to the json_type in jansson.h
+///
+typedef enum {
+    EdkiiJsonTypeObject,
+    EdkiiJsonTypeArray,
+    EdkiiJsonTypeString,
+    EdkiiJsonTypeInteger,
+    EdkiiJsonTypeReal,
+    EdkiiJsonTypeTrue,
+    EdkiiJsonTypeFalse,
+    EdkiiJsonTypeNull
+} EDKII_JSON_TYPE;
+
+/**
+  The function is used to convert a NULL terminated UTF8 encoded string to a JSON
+  value. Only object and array represented strings can be converted successfully,
+  since they are the only valid root values of a JSON text for UEFI usage.
+
+  Real number and number with exponent part are not supportted by UEFI.
+
+  Caller needs to cleanup the root value by calling JsonValueFree().
+
+  @param[in]   Text             The NULL terminated UTF8 encoded string to convert
+
+  @retval      Array JSON value or object JSON value, or NULL when any error occurs.
+
+**/
+EDKII_JSON_VALUE
+EFIAPI
+TextToJson (
+  IN    CHAR8*    Text
+  );
+
+/**
+  The function is used to convert the JSON root value to a UTF8 encoded string which
+  is terminated by NULL, or return NULL on error.
+
+  Only array JSON value or object JSON value is valid for converting, and caller is
+  responsible for free converted string.
+
+  @param[in]   Json               The JSON value to be converted
+
+  @retval      The JSON value converted UTF8 string or NULL.
+
+**/
+CHAR8*
+EFIAPI
+JsonToText (
+  IN    EDKII_JSON_VALUE    Json
+  );
+
+/**
+  The function is used to initialize a JSON value which contains a new JSON array,
+  or NULL on error. Initially, the array is empty.
+
+  The reference count of this value will be set to 1, and caller needs to cleanup the
+  value by calling JsonValueFree().
+
+  More details for reference count strategy can refer to the API description for JsonValueFree().
+
+  @retval      The created JSON value which contains a JSON array or NULL.
+
+**/
+EDKII_JSON_VALUE
+EFIAPI
+JsonValueInitArray (
+  VOID
+  );
+
+/**
+  The function is used to initialize a JSON value which contains a new JSON object,
+  or NULL on error. Initially, the object is empty.
+
+  The reference count of this value will be set to 1, and caller needs to cleanup the
+  value by calling JsonValueFree().
+
+  More details for reference count strategy can refer to the API description for JsonValueFree().
+
+  @retval      The created JSON value which contains a JSON object or NULL.
+
+**/
+EDKII_JSON_VALUE
+EFIAPI
+JsonValueInitObject (
+  VOID
+  );
+
+/**
+  The function is used to initialize a JSON value which contains a new JSON string,
+  or NULL on error.
+
+  The input string must be NULL terminated Ascii format, non-Ascii characters will
+  be processed as an error. Unicode characters can also be represented by Ascii string
+  as the format: \u + 4 hexadecimal digits, like \u3E5A, or \u003F.
+
+  The reference count of this value will be set to 1, and caller needs to cleanup the
+  value by calling JsonValueFree().
+
+  More details for reference count strategy can refer to the API description for JsonValueFree().
+
+  @param[in]   String      The Ascii string to initialize to JSON value
+
+  @retval      The created JSON value which contains a JSON string or NULL. Select a
+               Getter API for a specific encoding format.
+
+**/
+EDKII_JSON_VALUE
+EFIAPI
+JsonValueInitAsciiString (
+  IN    CONST CHAR8    *String
+  );
+
+/**
+  The function is used to initialize a JSON value which contains a new JSON string,
+  or NULL on error.
+
+  The input must be a NULL terminated UCS2 format Unicode string.
+
+  The reference count of this value will be set to 1, and caller needs to cleanup the
+  value by calling JsonValueFree().
+
+  More details for reference count strategy can refer to the API description for JsonValueFree().
+
+  @param[in]   String      The Unicode string to initialize to JSON value
+
+  @retval      The created JSON value which contains a JSON string or NULL. Select a
+               Getter API for a specific encoding format.
+
+**/
+EDKII_JSON_VALUE
+EFIAPI
+JsonValueInitUnicodeString (
+  IN    CHAR16    *String
+  );
+
+/**
+  The function is used to initialize a JSON value which contains a new JSON integer,
+  or NULL on error.
+
+  The reference count of this value will be set to 1, and caller needs to cleanup the
+  value by calling JsonValueFree().
+
+  More details for reference count strategy can refer to the API description for JsonValueFree().
+
+  @param[in]   Value       The integer to initialize to JSON value
+
+  @retval      The created JSON value which contains a JSON number or NULL.
+
+**/
+EDKII_JSON_VALUE
+EFIAPI
+JsonValueInitNumber (
+  IN    INT64    Value
+  );
+
+/**
+  The function is used to initialize a JSON value which contains a new JSON boolean,
+  or NULL on error.
+
+  Boolean JSON value is kept as static value, and no need to do any cleanup work.
+
+  @param[in]   Value       The boolean value to initialize.
+
+  @retval      The created JSON value which contains a JSON boolean or NULL.
+
+**/
+EDKII_JSON_VALUE
+EFIAPI
+JsonValueInitBoolean (
+  IN    BOOLEAN    Value
+  );
+
+/**
+  The function is used to initialize a JSON value which contains a new JSON NULL,
+  or NULL on error.
+
+  NULL JSON value is kept as static value, and no need to do any cleanup work.
+
+  @retval      The created NULL JSON value.
+
+**/
+EDKII_JSON_VALUE
+EFIAPI
+JsonValueInitNull (
+  VOID
+  );
+
+/**
+  The function is used to decrease the reference count of a JSON value by one, and once
+  this reference count drops to zero, the value is destroyed and it can no longer be used.
+  If this destroyed value is object type or array type, reference counts for all containing
+  JSON values will be decreased by 1. Boolean JSON value and NULL JSON value won't be destroyed
+  since they are static values kept in memory.
+
+  Reference Count Strategy: BaseJsonLib uses this strategy to track whether a value is still
+  in use or not. When a value is created, it's reference count is set to 1. If a reference to a
+  value is kept for use, its reference count is incremented, and when the value is no longer
+  needed, the reference count is decremented. When the reference count drops to zero, there are
+  no references left, and the value can be destroyed.
+
+  The given JSON value maybe NULL and not causing any problem. Just output the debug message
+  to inform caller the NULL value is passed in.
+
+  @param[in]   Json             The JSON value to be freed. json_decref may return without any
+                                changes if Json is NULL.
+
+**/
+VOID
+EFIAPI
+JsonValueFree (
+  IN    EDKII_JSON_VALUE    Json
+  );
+
+/**
+  The function is used to create a fresh copy of a JSON value, and all child values are deep
+  copied in a recursive fashion. It should be called when this JSON value might be modified
+  in later use, but the original still wants to be used in somewhere else.
+
+  Reference counts of the returned root JSON value and all child values will be set to 1, and
+  caller needs to cleanup the root value by calling JsonValueFree().
+
+  * Note: Since this function performs a copy from bottom to up, too many calls may cause some
+  performance issues, user should avoid unnecessary calls to this function unless it is really
+  needed.
+
+  @param[in]   Json             The JSON value to be cloned.
+
+  @retval      Return the cloned JSON value, or NULL on error.
+
+**/
+EDKII_JSON_VALUE
+EFIAPI
+JsonValueClone (
+  IN    EDKII_JSON_VALUE    Json
+  );
+
+/**
+  The function is used to return if the provided JSON value contains a JSON array.
+
+  @param[in]   Json             The provided JSON value.
+
+  @retval      TRUE             The JSON value contains a JSON array.
+  @retval      FALSE            The JSON value doesn't contain a JSON array.
+
+**/
+BOOLEAN
+EFIAPI
+JsonValueIsArray (
+  IN    EDKII_JSON_VALUE    Json
+  );
+
+/**
+  The function is used to return if the provided JSON value contains a JSON object.
+
+  @param[in]   Json             The provided JSON value.
+
+  @retval      TRUE             The JSON value contains a JSON object.
+  @retval      FALSE            The JSON value doesn't contain a JSON object.
+
+**/
+BOOLEAN
+EFIAPI
+JsonValueIsObject (
+  IN    EDKII_JSON_VALUE    Json
+  );
+
+/**
+  The function is used to return if the provided JSON Value contains a string, Ascii or
+  Unicode format is not differentiated.
+
+  @param[in]   Json             The provided JSON value.
+
+  @retval      TRUE             The JSON value contains a JSON string.
+  @retval      FALSE            The JSON value doesn't contain a JSON string.
+
+**/
+BOOLEAN
+EFIAPI
+JsonValueIsString (
+  IN    EDKII_JSON_VALUE    Json
+  );
+
+/**
+  The function is used to return if the provided JSON value contains a JSON number.
+
+  @param[in]   Json             The provided JSON value.
+
+  @retval      TRUE             The JSON value is contains JSON number.
+  @retval      FALSE            The JSON value doesn't contain a JSON number.
+
+**/
+BOOLEAN
+EFIAPI
+JsonValueIsNumber (
+  IN    EDKII_JSON_VALUE    Json
+  );
+
+/**
+  The function is used to return if the provided JSON value contains a JSON boolean.
+
+  @param[in]   Json             The provided JSON value.
+
+  @retval      TRUE             The JSON value contains a JSON boolean.
+  @retval      FALSE            The JSON value doesn't contain a JSON boolean.
+
+**/
+BOOLEAN
+EFIAPI
+JsonValueIsBoolean (
+  IN    EDKII_JSON_VALUE    Json
+  );
+
+/**
+  The function is used to return if the provided JSON value contains a JSON NULL.
+
+  @param[in]   Json             The provided JSON value.
+
+  @retval      TRUE             The JSON value contains a JSON NULL.
+  @retval      FALSE            The JSON value doesn't contain a JSON NULL.
+
+**/
+BOOLEAN
+EFIAPI
+JsonValueIsNull (
+  IN    EDKII_JSON_VALUE    Json
+  );
+
+/**
+  The function is used to retrieve the associated array in an array type JSON value.
+
+  Any changes to the returned array will impact the original JSON value.
+
+  @param[in]   Json             The provided JSON value.
+
+  @retval      Return the associated array in JSON value or NULL.
+
+**/
+EDKII_JSON_ARRAY
+EFIAPI
+JsonValueGetArray (
+  IN    EDKII_JSON_VALUE    Json
+  );
+
+/**
+  The function is used to retrieve the associated object in an object type JSON value.
+
+  Any changes to the returned object will impact the original JSON value.
+
+  @param[in]   Json             The provided JSON value.
+
+  @retval      Return the associated object in JSON value or NULL.
+
+**/
+EDKII_JSON_OBJECT
+EFIAPI
+JsonValueGetObject (
+  IN    EDKII_JSON_VALUE    Json
+  );
+
+/**
+  The function is used to retrieve the associated Ascii string in a string type JSON value.
+
+  Any changes to the returned string will impact the original JSON value.
+
+  @param[in]   Json             The provided JSON value.
+
+  @retval      Return the associated Ascii string in JSON value or NULL.
+
+**/
+CHAR8*
+EFIAPI
+JsonValueGetAsciiString (
+  IN    EDKII_JSON_VALUE    Json
+  );
+
+/**
+  The function is used to retrieve the associated Unicode string in a string type JSON value.
+
+  Caller can do any changes to the returned string without any impact to the original JSON
+  value, and caller needs to free the returned string.
+
+  @param[in]   Json             The provided JSON value.
+
+  @retval      Return the associated Unicode string in JSON value or NULL.
+
+**/
+CHAR16*
+EFIAPI
+JsonValueGetUnicodeString (
+  IN    EDKII_JSON_VALUE    Json
+  );
+
+/**
+  The function is used to retrieve the associated integer in a number type JSON value.
+
+  The input JSON value should not be NULL or contain no JSON number, otherwise it will
+  ASSERT() and return 0.
+
+  @param[in]   Json             The provided JSON value.
+
+  @retval      Return the associated number in JSON value.
+
+**/
+INT64
+EFIAPI
+JsonValueGetNumber (
+  IN    EDKII_JSON_VALUE    Json
+  );
+
+/**
+  The function is used to retrieve the associated boolean in a boolean type JSON value.
+
+  The input JSON value should not be NULL or contain no JSON boolean, otherwise it will
+  ASSERT() and return FALSE.
+
+  @param[in]   Json             The provided JSON value.
+
+  @retval      Return the associated value of JSON boolean.
+
+**/
+BOOLEAN
+EFIAPI
+JsonValueGetBoolean (
+  IN    EDKII_JSON_VALUE    Json
+  );
+
+/**
+  The function is used to retrieve the associated string in a string type JSON value.
+
+  Any changes to the returned string will impact the original JSON value.
+
+  @param[in]   Json             The provided JSON value.
+
+  @retval      Return the associated Ascii string in JSON value or NULL.
+
+**/
+CONST CHAR8*
+EFIAPI
+JsonValueGetString (
+  IN    EDKII_JSON_VALUE    Json
+  );
+
+/**
+  The function is used to get the number of elements in a JSON object, or 0 if it is NULL or
+  not a JSON object.
+
+  @param[in]   JsonObject              The provided JSON object.
+
+  @retval      Return the number of elements in this JSON object or 0.
+
+**/
+UINTN
+EFIAPI
+JsonObjectSize (
+  IN    EDKII_JSON_OBJECT    JsonObject
+  );
+
+/**
+  The function is used to enumerate all keys in a JSON object.
+
+  Caller should be responsible to free the returned key array refference. But contained keys
+  are read only and must not be modified or freed.
+
+  @param[in]   JsonObj                The provided JSON object for enumeration.
+  @param[out]  KeyCount               The count of keys in this JSON object.
+
+  @retval      Return an array of the enumerated keys in this JSON object or NULL.
+
+**/
+CHAR8**
+JsonObjectGetKeys (
+  IN    EDKII_JSON_OBJECT    JsonObj,
+  OUT   UINTN                *KeyCount
+  );
+
+/**
+  The function is used to get a JSON value corresponding to the input key from a JSON object.
+
+  It only returns a reference to this value and any changes on this value will impact the
+  original JSON object. If that is not expected, please call JsonValueClone() to clone it to
+  use.
+
+  Input key must be a valid NULL terminated UTF8 encoded string. NULL will be returned when
+  Key-Value is not found in this JSON object.
+
+  @param[in]   JsonObj           The provided JSON object.
+  @param[in]   Key               The key of the JSON value to be retrieved.
+
+  @retval      Return the corresponding JSON value to key, or NULL on error.
+
+**/
+EDKII_JSON_VALUE
+EFIAPI
+JsonObjectGetValue (
+  IN    CONST EDKII_JSON_OBJECT    JsonObj,
+  IN    CONST CHAR8                *Key
+  );
+
+/**
+  The function is used to set a JSON value corresponding to the input key from a JSON object,
+  and the reference count of this value will be increased by 1.
+
+  Input key must be a valid NULL terminated UTF8 encoded string. If there already is a value for
+  this key, this key will be assigned to the new JSON value. The old JSON value will be removed
+  from this object and thus its' reference count will be decreased by 1.
+
+  More details for reference count strategy can refer to the API description for JsonValueFree().
+
+  @param[in]   JsonObj                The provided JSON object.
+  @param[in]   Key                    The key of the JSON value to be set.
+  @param[in]   Json                   The JSON value to set to this JSON object mapped by key.
+
+  @retval      EFI_ABORTED            Some error occur and operation aborted.
+  @retval      EFI_SUCCESS            The JSON value has been set to this JSON object.
+
+**/
+EFI_STATUS
+EFIAPI
+JsonObjectSetValue (
+  IN    EDKII_JSON_OBJECT    JsonObj,
+  IN    CONST CHAR8          *Key,
+  IN    EDKII_JSON_VALUE     Json
+  );
+
+/**
+  The function is used to get the number of elements in a JSON array, or 0 if it is NULL or
+  not a JSON array.
+
+  @param[in]   JsonArray              The provided JSON array.
+
+  @retval      Return the number of elements in this JSON array or 0.
+
+**/
+UINTN
+EFIAPI
+JsonArrayCount (
+  IN    EDKII_JSON_ARRAY    JsonArray
+  );
+
+/**
+  The function is used to return the JSON value in the array at position index. The valid range
+  for this index is from 0 to the return value of JsonArrayCount() minus 1.
+
+  It only returns a reference to this value and any changes on this value will impact the
+  original JSON object. If that is not expected, please call JsonValueClone() to clone it to
+  use.
+
+  If this array is NULL or not a JSON array, or if index is out of range, NULL will be returned.
+
+  @param[in]   JsonArray         The provided JSON Array.
+
+  @retval      Return the JSON value located in the Index position or NULL.
+
+**/
+EDKII_JSON_VALUE
+EFIAPI
+JsonArrayGetValue (
+  IN    EDKII_JSON_ARRAY    JsonArray,
+  IN    UINTN               Index
+  );
+
+/**
+  The function is used to append a JSON value to the end of the JSON array, and grow the size of
+  array by 1. The reference count of this value will be increased by 1.
+
+  More details for reference count strategy can refer to the API description for JsonValueFree().
+
+  @param[in]   JsonArray              The provided JSON object.
+  @param[in]   Json                   The JSON value to append.
+
+  @retval      EFI_ABORTED            Some error occur and operation aborted.
+  @retval      EFI_SUCCESS            JSON value has been appended to the end of the JSON array.
+
+**/
+EFI_STATUS
+EFIAPI
+JsonArrayAppendValue (
+  IN    EDKII_JSON_ARRAY    JsonArray,
+  IN    EDKII_JSON_VALUE    Json
+  );
+
+/**
+  The function is used to remove a JSON value at position index, shifting the elements after index
+  one position towards the start of the array. The reference count of this value will be decreased
+  by 1.
+
+  More details for reference count strategy can refer to the API description for JsonValueFree().
+
+  @param[in]   JsonArray              The provided JSON array.
+  @param[in]   Index                  The Index position before removement.
+
+  @retval      EFI_ABORTED            Some error occur and operation aborted.
+  @retval      EFI_SUCCESS            The JSON array has been removed at position index.
+
+**/
+EFI_STATUS
+EFIAPI
+JsonArrayRemoveValue (
+  IN    EDKII_JSON_ARRAY    JsonArray,
+  IN    UINTN               Index
+  );
+
+/**
+  Dump JSON to a buffer
+
+  @param[in]   JsonValue       The provided JSON array.
+  @param[in]   Index           The Index position before removement.
+
+  @retval      NULL            Dump fail if NULL returned, otherwise the buffer
+                               contain JSON paylaod in ASCII string.
+**/
+CHAR8 *
+EFIAPI
+JsonDumpString (
+  IN    EDKII_JSON_ARRAY    JsonValue,
+  IN    UINTN               Flags
+  );
+
+/**
+  Load JSON from a buffer
+
+  @param[in]   Buffer        Bufffer to the JSON payload
+  @param[in]   BufferLen     Length of the buffer
+  @param[in]   Flags         Flag of loading JSON buffer
+
+  @retval      EDKII_JSON_VALUE  NULL means fail to load JSON payload.
+**/
+EDKII_JSON_VALUE
+EFIAPI
+JsonLoadBuffer (
+  IN    CONST CHAR8       *Buffer,
+  IN    UINTN             BufferLen,
+  IN    UINTN             Flags,
+  IN    EDKII_JSON_ERROR  *Error
+  );
+
+/**
+  Decrease reference
+
+  @param[in]   JsonValue      JSON value
+**/
+VOID
+EFIAPI
+JsonDecreaseReference (
+  IN EDKII_JSON_VALUE JsonValue
+  );
+
+/**
+  Increase reference
+
+  @param[in]   JsonValue      JSON value
+  @retval      EDKII_JSON_VALUE of itself
+**/
+EDKII_JSON_VALUE
+EFIAPI
+JsonIncreaseReference (
+  IN EDKII_JSON_VALUE JsonValue
+  );
+/**
+  Returns an opaque iterator which can be used to iterate over all key-value pairs
+  in object, or NULL if object is empty
+
+  @param[in]   JsonValue      JSON value
+**/
+VOID *
+EFIAPI
+JsonObjectIterator (
+  IN EDKII_JSON_VALUE JsonValue
+  );
+
+/**
+  Extract the associated value from iterator.
+
+  @param[in]   Iterator   Iterator pointer
+**/
+EDKII_JSON_VALUE
+EFIAPI
+JsonObjectIteratorValue (
+  IN VOID *Iterator
+  );
+
+/**
+  Returns an iterator pointing to the next key-value pair in object after iter,
+  or NULL if the whole object has been iterated through.
+
+  @param[in]   JsonValue  JSON value
+  @param[in]   Iterator   Iterator pointer
+  @retval      Iterator pointer
+**/
+VOID *
+JsonObjectIteratorNext (
+  IN EDKII_JSON_VALUE JsonValue,
+  IN VOID             *Iterator
+  );
+
+/**
+  Returns the json type of this json value
+
+  @param[in]   JsonValue  JSON value
+  @retval      JSON type returned
+**/
+EDKII_JSON_TYPE
+EFIAPI
+JsonGetType(
+  IN EDKII_JSON_VALUE JsonValue
+  );
+#endif
diff --git a/RedfishPkg/Library/JsonLib/JanssonCrtLibSupport.c b/RedfishPkg/Library/JsonLib/JanssonCrtLibSupport.c
new file mode 100644
index 0000000000..907634a05b
--- /dev/null
+++ b/RedfishPkg/Library/JsonLib/JanssonCrtLibSupport.c
@@ -0,0 +1,705 @@
+/** @file
+  CRT wrapper functions for Jansson system call.
+
+  Copyright (c) 2019, Intel Corporation. All rights reserved.<BR>
+ (C) Copyright 2020 Hewlett Packard Enterprise Development LP<BR>
+
+    SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#include <JanssonCrtLibSupport.h>
+#include <Library/MemoryAllocationLib.h>
+#include <Library/UefiRuntimeServicesTableLib.h>
+
+int  errno = 0;
+
+/**
+  Determine if a particular character is an alphanumeric character
+  @return  Returns 1 if c is an alphanumeric character, otherwise returns 0.
+**/
+int isalnum (int c)
+{
+  //
+  // <alnum> ::= [0-9] | [a-z] | [A-Z]
+  //
+  return ((('0' <= (c)) && ((c) <= '9')) ||
+          (('a' <= (c)) && ((c) <= 'z')) ||
+          (('A' <= (c)) && ((c) <= 'Z')));
+}
+
+/**
+  Determine if a particular character is a digital character
+
+  @return  Returns 1 if c is an digital character, otherwise returns 0.
+**/
+int isdchar (int c)
+{
+  //
+  // [0-9] | [e +-.]
+  //
+  return ((('0' <= (c)) && ((c) <= '9')) ||
+          (c == 'e') || (c == 'E') ||
+          (c == '+') || (c == '-') ||
+          (c == '.'));
+}
+
+/**
+  Determine if a particular character is a space character
+
+  @return  Returns 1 if c is a space character
+**/
+int isspace (int c)
+{
+  //
+  // <space> ::= [ ]
+  //
+  return ((c) == ' ') || ((c) == '\t') || ((c) == '\r') || ((c) == '\n') || ((c) == '\v')  || ((c) == '\f');
+}
+
+/**
+  Allocates memory blocks
+*/
+void *malloc (size_t size)
+{
+  return AllocatePool ((UINTN) size);
+}
+
+/**
+  De-allocates or frees a memory block
+*/
+void free (void *ptr)
+{
+  //
+  // In Standard C, free() handles a null pointer argument transparently. This
+  // is not true of FreePool() below, so protect it.
+  //
+  if (ptr != NULL) {
+    FreePool (ptr);
+  }
+}
+
+/**
+  NetBSD Compatibility Function strdup creates a duplicate copy of a string.
+
+  @return  Returns the pointer to duplicated string.
+**/
+char * strdup(const char *str)
+{
+  size_t len;
+  char *copy;
+
+  len = strlen(str) + 1;
+  if ((copy = malloc(len)) == NULL)
+    return (NULL);
+  memcpy(copy, str, len);
+  return (copy);
+}
+
+/** The toupper function converts a lowercase letter to a corresponding
+    uppercase letter.
+
+    @param[in]    c   The character to be converted.
+
+    @return   If the argument is a character for which islower is true and
+              there are one or more corresponding characters, as specified by
+              the current locale, for which isupper is true, the toupper
+              function returns one of the corresponding characters (always the
+              same one for any given locale); otherwise, the argument is
+              returned unchanged.
+**/
+int
+toupper(
+  IN  int c
+  )
+{
+  if ( (c >= 'a') && (c <= 'z') ) {
+    c = c - ('a' - 'A');
+  }
+  return c;
+}
+
+/**
+  Digit to a value.
+
+  @return  Returns the value of digit.
+**/
+int
+Digit2Val( int c)
+{
+  if (((c >= 'a') && (c <= 'z')) || ((c >= 'A') && (c <= 'Z'))) {  /* If c is one of [A-Za-z]... */
+    c = toupper(c) - 7;   // Adjust so 'A' is ('9' + 1)
+  }
+  return c - '0';   // Value returned is between 0 and 35, inclusive.
+}
+
+
+/** The strtoll function converts the initial portion of the string pointed to
+    by nptr to long long int representation.
+
+    See the description for strtol for more information.
+
+  @return   The strtoll function returns the converted value, if any. If no
+            conversion could be performed, zero is returned. If the correct
+            value is outside the range of representable values, LLONG_MIN or
+            LLONG_MAX is returned (according to the sign of the value, if any),
+            and the value of the macro ERANGE is stored in errno.
+**/
+long long
+strtoll(const char * nptr, char ** endptr, int base)
+{
+  const char *pEnd;
+  long long   Result = 0;
+  long long   Previous;
+  int         temp;
+  BOOLEAN     Negative = FALSE;
+
+  pEnd = nptr;
+
+  if((base < 0) || (base == 1) || (base > 36)) {
+    if(endptr != NULL) {
+    *endptr = NULL;
+    }
+    return 0;
+  }
+  // Skip leading spaces.
+  while(isspace(*nptr))   ++nptr;
+
+  // Process Subject sequence: optional sign followed by digits.
+  if(*nptr == '+') {
+    Negative = FALSE;
+    ++nptr;
+  }
+  else if(*nptr == '-') {
+    Negative = TRUE;
+    ++nptr;
+  }
+
+  if(*nptr == '0') {  /* Might be Octal or Hex */
+    if(toupper(nptr[1]) == 'X') {   /* Looks like Hex */
+      if((base == 0) || (base == 16)) {
+        nptr += 2;  /* Skip the "0X"      */
+        base = 16;  /* In case base was 0 */
+      }
+    }
+    else {    /* Looks like Octal */
+      if((base == 0) || (base == 8)) {
+        ++nptr;     /* Skip the leading "0" */
+        base = 8;   /* In case base was 0   */
+      }
+    }
+  }
+  if(base == 0) {   /* If still zero then must be decimal */
+    base = 10;
+  }
+  if(*nptr  == '0') {
+    for( ; *nptr == '0'; ++nptr);  /* Skip any remaining leading zeros */
+    pEnd = nptr;
+  }
+
+  while( isalnum(*nptr) && ((temp = Digit2Val(*nptr)) < base)) {
+    Previous = Result;
+    Result = MultS64x64 (Result, base) + (long long int)temp;
+    if( Result <= Previous) {   // Detect Overflow
+      if(Negative) {
+        Result = LLONG_MIN;
+      }
+      else {
+        Result = LLONG_MAX;
+      }
+      Negative = FALSE;
+      errno = ERANGE;
+      break;
+    }
+    pEnd = ++nptr;
+  }
+  if(Negative) {
+    Result = -Result;
+  }
+
+  // Save pointer to final sequence
+  if(endptr != NULL) {
+    *endptr = (char *)pEnd;
+  }
+  return Result;
+}
+
+/** The strtol, strtoll, strtoul, and strtoull functions convert the initial
+    portion of the string pointed to by nptr to long int, long long int,
+    unsigned long int, and unsigned long long int representation, respectively.
+    First, they decompose the input string into three parts: an initial,
+    possibly empty, sequence of white-space characters (as specified by the
+    isspace function), a subject sequence resembling an integer represented in
+    some radix determined by the value of base, and a final string of one or
+    more unrecognized characters, including the terminating null character of
+    the input string. Then, they attempt to convert the subject sequence to an
+    integer, and return the result.
+
+    If the value of base is zero, the expected form of the subject sequence is
+    that of an integer constant, optionally preceded
+    by a plus or minus sign, but not including an integer suffix. If the value
+    of base is between 2 and 36 (inclusive), the expected form of the subject
+    sequence is a sequence of letters and digits representing an integer with
+    the radix specified by base, optionally preceded by a plus or minus sign,
+    but not including an integer suffix. The letters from a (or A) through z
+    (or Z) are ascribed the values 10 through 35; only letters and digits whose
+    ascribed values are less than that of base are permitted. If the value of
+    base is 16, the characters 0x or 0X may optionally precede the sequence of
+    letters and digits, following the sign if present.
+
+    The subject sequence is defined as the longest initial subsequence of the
+    input string, starting with the first non-white-space character, that is of
+    the expected form. The subject sequence contains no characters if the input
+    string is empty or consists entirely of white space, or if the first
+    non-white-space character is other than a sign or a permissible letter or digit.
+
+    If the subject sequence has the expected form and the value of base is
+    zero, the sequence of characters starting with the first digit is
+    interpreted as an integer constant. If the subject sequence has the
+    expected form and the value of base is between 2 and 36, it is used as the
+    base for conversion, ascribing to each letter its value as given above. If
+    the subject sequence begins with a minus sign, the value resulting from the
+    conversion is negated (in the return type). A pointer to the final string
+    is stored in the object pointed to by endptr, provided that endptr is
+    not a null pointer.
+
+    In other than the "C" locale, additional locale-specific subject sequence
+    forms may be accepted.
+
+    If the subject sequence is empty or does not have the expected form, no
+    conversion is performed; the value of nptr is stored in the object pointed
+    to by endptr, provided that endptr is not a null pointer.
+
+  @return   The strtol, strtoll, strtoul, and strtoull functions return the
+            converted value, if any. If no conversion could be performed, zero
+            is returned. If the correct value is outside the range of
+            representable values, LONG_MIN, LONG_MAX, LLONG_MIN, LLONG_MAX,
+            ULONG_MAX, or ULLONG_MAX is returned (according to the return type
+            and sign of the value, if any), and the value of the macro ERANGE
+            is stored in errno.
+**/
+long
+strtol(const char * nptr, char ** endptr, int base)
+{
+  const char *pEnd;
+  long        Result = 0;
+  long        Previous;
+  int         temp;
+  BOOLEAN     Negative = FALSE;
+
+  pEnd = nptr;
+
+  if((base < 0) || (base == 1) || (base > 36)) {
+    if(endptr != NULL) {
+    *endptr = NULL;
+    }
+    return 0;
+  }
+  // Skip leading spaces.
+  while(isspace(*nptr))   ++nptr;
+
+  // Process Subject sequence: optional sign followed by digits.
+  if(*nptr == '+') {
+    Negative = FALSE;
+    ++nptr;
+  }
+  else if(*nptr == '-') {
+    Negative = TRUE;
+    ++nptr;
+  }
+
+  if(*nptr == '0') {  /* Might be Octal or Hex */
+    if(toupper(nptr[1]) == 'X') {   /* Looks like Hex */
+      if((base == 0) || (base == 16)) {
+        nptr += 2;  /* Skip the "0X"      */
+        base = 16;  /* In case base was 0 */
+      }
+    }
+    else {    /* Looks like Octal */
+      if((base == 0) || (base == 8)) {
+        ++nptr;     /* Skip the leading "0" */
+        base = 8;   /* In case base was 0   */
+      }
+    }
+  }
+  if(base == 0) {   /* If still zero then must be decimal */
+    base = 10;
+  }
+  if(*nptr  == '0') {
+    for( ; *nptr == '0'; ++nptr);  /* Skip any remaining leading zeros */
+    pEnd = nptr;
+  }
+
+  while( isalnum(*nptr) && ((temp = Digit2Val(*nptr)) < base)) {
+    Previous = Result;
+    Result = (Result * base) + (long int)temp;
+    if( Result <= Previous) {   // Detect Overflow
+      if(Negative) {
+        Result = LONG_MIN;
+      }
+      else {
+        Result = LONG_MAX;
+      }
+      Negative = FALSE;
+      errno = ERANGE;
+      break;
+    }
+    pEnd = ++nptr;
+  }
+  if(Negative) {
+    Result = -Result;
+  }
+
+  // Save pointer to final sequence
+  if(endptr != NULL) {
+    *endptr = (char *)pEnd;
+  }
+  return Result;
+}
+
+/** The strtoull function converts the initial portion of the string pointed to
+    by nptr to unsigned long long int representation.
+
+    See the description for strtol for more information.
+
+  @return   The strtoull function returns the converted value, if any. If no
+            conversion could be performed, zero is returned. If the correct
+            value is outside the range of representable values, ULLONG_MAX is
+            returned and the value of the macro ERANGE is stored in errno.
+**/
+unsigned long long
+strtoull(const char * nptr, char ** endptr, int base)
+{
+  const char           *pEnd;
+  unsigned long long    Result = 0;
+  unsigned long long    Previous;
+  int                   temp;
+
+  pEnd = nptr;
+
+  if((base < 0) || (base == 1) || (base > 36)) {
+    if(endptr != NULL) {
+    *endptr = NULL;
+    }
+    return 0;
+  }
+  // Skip leading spaces.
+  while(isspace(*nptr))   ++nptr;
+
+  // Process Subject sequence: optional + sign followed by digits.
+  if(*nptr == '+') {
+    ++nptr;
+  }
+
+  if(*nptr == '0') {  /* Might be Octal or Hex */
+    if(toupper(nptr[1]) == 'X') {   /* Looks like Hex */
+      if((base == 0) || (base == 16)) {
+        nptr += 2;  /* Skip the "0X"      */
+        base = 16;  /* In case base was 0 */
+      }
+    }
+    else {    /* Looks like Octal */
+      if((base == 0) || (base == 8)) {
+        ++nptr;     /* Skip the leading "0" */
+        base = 8;   /* In case base was 0   */
+      }
+    }
+  }
+  if(base == 0) {   /* If still zero then must be decimal */
+    base = 10;
+  }
+  if(*nptr  == '0') {
+    for( ; *nptr == '0'; ++nptr);  /* Skip any remaining leading zeros */
+    pEnd = nptr;
+  }
+
+  while( isalnum(*nptr) && ((temp = Digit2Val(*nptr)) < base)) {
+    Previous = Result;
+    Result = DivU64x32 (Result, base) + (unsigned long long)temp;
+    if( Result < Previous)  {   // If we overflowed
+      Result = ULLONG_MAX;
+      errno = ERANGE;
+      break;
+    }
+    pEnd = ++nptr;
+  }
+
+  // Save pointer to final sequence
+  if(endptr != NULL) {
+    *endptr = (char *)pEnd;
+  }
+  return Result;
+}
+
+/**
+  edk2 Jansson port does not support doubles, simply return 0.
+
+  These conversion functions convert the initial portion of the string
+  pointed to by nptr to double, float, and long double representation,
+  respectively.
+
+  The strtod(), strtof(), and strtold() functions return the converted
+  value, if any.
+
+  If endptr is not NULL, a pointer to the character after the last charac-
+  ter used in the conversion is stored in the location referenced by
+  endptr.
+
+  If no conversion is performed, zero is returned and the value of nptr is
+  stored in the location referenced by endptr.
+
+  If the correct value would cause overflow, plus or minus HUGE_VAL,
+  HUGE_VALF, or HUGE_VALL is returned (according to the sign and type of
+  the return value), and ERANGE is stored in errno.  If the correct value
+  would cause underflow, zero is returned and ERANGE is stored in errno.
+
+  @return  Return 0.
+**/
+double
+strtod (const char * __restrict nptr, char ** __restrict endptr) {
+    if(endptr)
+      *endptr = (char *)(nptr + strlen(nptr));
+
+    return (double)0;
+}
+
+/**
+  Allocate and zero-initialize array.
+**/
+void *
+calloc(size_t Num, size_t Size)
+{
+  void       *RetVal;
+  size_t      NumSize;
+
+  NumSize = Num * Size;
+  RetVal  = NULL;
+  if (NumSize != 0) {
+  RetVal = malloc(NumSize);
+  if( RetVal != NULL) {
+    (VOID)ZeroMem( RetVal, NumSize);
+  }
+  }
+  DEBUG((DEBUG_POOL, "0x%p = calloc(%d, %d)\n", RetVal, Num, Size));
+
+  return RetVal;
+}
+
+//
+//  The arrays give the cumulative number of days up to the first of the
+//  month number used as the index (1 -> 12) for regular and leap years.
+//  The value at index 13 is for the whole year.
+//
+UINTN CumulativeDays[2][14] = {
+  {
+    0,
+    0,
+    31,
+    31 + 28,
+    31 + 28 + 31,
+    31 + 28 + 31 + 30,
+    31 + 28 + 31 + 30 + 31,
+    31 + 28 + 31 + 30 + 31 + 30,
+    31 + 28 + 31 + 30 + 31 + 30 + 31,
+    31 + 28 + 31 + 30 + 31 + 30 + 31 + 31,
+    31 + 28 + 31 + 30 + 31 + 30 + 31 + 31 + 30,
+    31 + 28 + 31 + 30 + 31 + 30 + 31 + 31 + 30 + 31,
+    31 + 28 + 31 + 30 + 31 + 30 + 31 + 31 + 30 + 31 + 30,
+    31 + 28 + 31 + 30 + 31 + 30 + 31 + 31 + 30 + 31 + 30 + 31
+  },
+  {
+    0,
+    0,
+    31,
+    31 + 29,
+    31 + 29 + 31,
+    31 + 29 + 31 + 30,
+    31 + 29 + 31 + 30 + 31,
+    31 + 29 + 31 + 30 + 31 + 30,
+    31 + 29 + 31 + 30 + 31 + 30 + 31,
+    31 + 29 + 31 + 30 + 31 + 30 + 31 + 31,
+    31 + 29 + 31 + 30 + 31 + 30 + 31 + 31 + 30,
+    31 + 29 + 31 + 30 + 31 + 30 + 31 + 31 + 30 + 31,
+    31 + 29 + 31 + 30 + 31 + 30 + 31 + 31 + 30 + 31 + 30,
+    31 + 29 + 31 + 30 + 31 + 30 + 31 + 31 + 30 + 31 + 30 + 31
+  }
+};
+
+#define IsLeap(y)   (((y) % 4) == 0 && (((y) % 100) != 0 || ((y) % 400) == 0))
+#define SECSPERMIN  (60)
+#define SECSPERHOUR (60 * 60)
+#define SECSPERDAY  (24 * SECSPERHOUR)
+
+/**
+  Get the system time as seconds elapsed since midnight, January 1, 1970.
+**/
+time_t time (time_t *timer)
+{
+  EFI_TIME  Time;
+  time_t    CalTime;
+  UINTN     Year;
+
+  //
+  // Get the current time and date information
+  //
+  gRT->GetTime (&Time, NULL);
+
+  //
+  // Years Handling
+  // UTime should now be set to 00:00:00 on Jan 1 of the current year.
+  //
+  for (Year = 1970, CalTime = 0; Year != Time.Year; Year++) {
+    CalTime = CalTime + (time_t)(CumulativeDays[IsLeap(Year)][13] * SECSPERDAY);
+  }
+
+  //
+  // Add in number of seconds for current Month, Day, Hour, Minute, Seconds, and TimeZone adjustment
+  //
+  CalTime = CalTime +
+            (time_t)((Time.TimeZone != EFI_UNSPECIFIED_TIMEZONE) ? (Time.TimeZone * 60) : 0) +
+            (time_t)(CumulativeDays[IsLeap(Time.Year)][Time.Month] * SECSPERDAY) +
+            (time_t)(((Time.Day > 0) ? Time.Day - 1 : 0) * SECSPERDAY) +
+            (time_t)(Time.Hour * SECSPERHOUR) +
+            (time_t)(Time.Minute * 60) +
+            (time_t)Time.Second;
+
+  if (timer != NULL) {
+    *timer = CalTime;
+  }
+
+  return CalTime;
+}
+
+typedef
+int
+(*SORT_COMPARE)(
+  IN  VOID  *Buffer1,
+  IN  VOID  *Buffer2
+  );
+
+/**
+  Duplicated from EDKII BaseSortLib for qsort() wrapper
+  @param[in, out] BufferToSort   on call a Buffer of (possibly sorted) elements
+                                 on return a buffer of sorted elements
+  @param[in] Count               the number of elements in the buffer to sort
+  @param[in] ElementSize         Size of an element in bytes
+  @param[in] CompareFunction     The function to call to perform the comparison
+                                 of any 2 elements
+  @param[in] Buffer              Buffer of size ElementSize for use in swapping
+**/
+STATIC
+VOID
+QuickSortWorker (
+  IN OUT    VOID          *BufferToSort,
+  IN CONST  UINTN         Count,
+  IN CONST  UINTN         ElementSize,
+  IN        SORT_COMPARE  CompareFunction,
+  IN        VOID          *Buffer
+  )
+{
+  VOID        *Pivot;
+  UINTN       LoopCount;
+  UINTN       NextSwapLocation;
+
+  ASSERT(BufferToSort    != NULL);
+  ASSERT(CompareFunction != NULL);
+  ASSERT(Buffer          != NULL);
+
+  if (Count < 2 || ElementSize  < 1) {
+    return;
+  }
+
+  NextSwapLocation = 0;
+
+  //
+  // Pick a pivot (we choose last element)
+  //
+  Pivot = ((UINT8 *)BufferToSort + ((Count - 1) * ElementSize));
+
+  //
+  // Now get the pivot such that all on "left" are below it
+  // and everything "right" are above it
+  //
+  for (LoopCount = 0; LoopCount < Count - 1;  LoopCount++)
+  {
+    //
+    // If the element is less than the pivot
+    //
+    if (CompareFunction ((VOID *)((UINT8 *)BufferToSort + ((LoopCount) * ElementSize)), Pivot) <= 0) {
+      //
+      // Swap
+      //
+      CopyMem (Buffer, (UINT8 *)BufferToSort + (NextSwapLocation * ElementSize), ElementSize);
+      CopyMem ((UINT8 *)BufferToSort + (NextSwapLocation * ElementSize), (UINT8 *)BufferToSort + ((LoopCount) * ElementSize), ElementSize);
+      CopyMem ((UINT8 *)BufferToSort + ((LoopCount) * ElementSize), Buffer, ElementSize);
+
+      //
+      // Increment NextSwapLocation
+      //
+      NextSwapLocation++;
+    }
+  }
+  //
+  // Swap pivot to it's final position (NextSwapLocaiton)
+  //
+  CopyMem (Buffer, Pivot, ElementSize);
+  CopyMem (Pivot, (UINT8 *)BufferToSort + (NextSwapLocation * ElementSize), ElementSize);
+  CopyMem ((UINT8 *)BufferToSort + (NextSwapLocation * ElementSize), Buffer, ElementSize);
+
+  //
+  // Now recurse on 2 paritial lists.  Neither of these will have the 'pivot' element.
+  // IE list is sorted left half, pivot element, sorted right half...
+  //
+  QuickSortWorker (
+    BufferToSort,
+    NextSwapLocation,
+    ElementSize,
+    CompareFunction,
+    Buffer
+    );
+
+  QuickSortWorker (
+    (UINT8 *)BufferToSort + (NextSwapLocation + 1) * ElementSize,
+    Count - NextSwapLocation - 1,
+    ElementSize,
+    CompareFunction,
+    Buffer
+    );
+
+  return;
+}
+
+/**
+  Performs a quick sort
+**/
+void qsort (void *base, size_t num, size_t width, int (*compare)(const void *, const void *))
+{
+  VOID  *Buffer;
+
+  ASSERT (base    != NULL);
+  ASSERT (compare != NULL);
+
+  //
+  // Use CRT-style malloc to cover BS and RT memory allocation.
+  //
+  Buffer = malloc (width);
+  ASSERT (Buffer != NULL);
+
+  //
+  // Re-use PerformQuickSort() function Implementation in EDKII BaseSortLib.
+  //
+  QuickSortWorker (base, (UINTN)num, (UINTN)width, (SORT_COMPARE)compare, Buffer);
+
+  free (Buffer);
+  return;
+}
+
+/**
+  Get character from stream, we don't support file operastion on edk2 JSON library.
+
+  @return Returns the character currently pointed by the internal file position indicator of the specified stream
+
+**/
+int fgetc(FILE * _File){
+   return 0;
+}
diff --git a/RedfishPkg/Library/JsonLib/JanssonCrtLibSupport.h b/RedfishPkg/Library/JsonLib/JanssonCrtLibSupport.h
new file mode 100644
index 0000000000..f17ee6397f
--- /dev/null
+++ b/RedfishPkg/Library/JsonLib/JanssonCrtLibSupport.h
@@ -0,0 +1,198 @@
+/** @file
+  CRT wrapper head functions for jansson system call.
+
+ Copyright (c) 2019, Intel Corporation. All rights reserved.<BR>
+ (C) Copyright 2020 Hewlett Packard Enterprise Development LP<BR>
+
+    SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#ifndef JANSSON_CRT_LIB_SUPPORT_H_
+#define JANSSON_CRT_LIB_SUPPORT_H_
+
+#include <Library/BaseLib.h>
+#include <Library/BaseMemoryLib.h>
+#include <Library/DebugLib.h>
+#include <Library/PrintLib.h>
+
+#define MAX_STRING_SIZE  0x10000000
+
+// Minimum value for an object of type long long int.
+#define LLONG_MIN   (-9223372036854775807LL - 1LL)  // -(2^63 - 1)
+
+// Maximum value for an object of type long long int.
+#define LLONG_MAX   9223372036854775807LL // 2^63 - 1
+
+// We dont support double on edk2
+#define HUGE_VAL    0
+
+#if defined(MDE_CPU_X64) || defined(MDE_CPU_AARCH64) || defined(MDE_CPU_IA64)
+//
+// With GCC we would normally use SIXTY_FOUR_BIT_LONG, but MSVC needs
+// SIXTY_FOUR_BIT, because 'long' is 32-bit and only 'long long' is
+// 64-bit. Since using 'long long' works fine on GCC too, just do that.
+//
+#define SIXTY_FOUR_BIT
+#elif defined(MDE_CPU_IA32) || defined(MDE_CPU_ARM) || defined(MDE_CPU_EBC)
+#define THIRTY_TWO_BIT
+#else
+#error Unknown target architecture
+#endif
+
+//
+// Map all va_xxxx elements to VA_xxx defined in MdePkg/Include/Base.h
+//
+#if !defined(__CC_ARM) // if va_list is not already defined
+#define va_list   VA_LIST
+#define va_arg    VA_ARG
+#define va_start  VA_START
+#define va_end    VA_END
+#else // __CC_ARM
+#define va_start(Marker, Parameter)   __va_start(Marker, Parameter)
+#define va_arg(Marker, TYPE)          __va_arg(Marker, TYPE)
+#define va_end(Marker)                ((void)0)
+#endif
+
+//
+// Definitions for global constants used by CRT library routines
+//
+#define EINVAL       22               /* Invalid argument */
+#define INT_MAX      0x7FFFFFFF       /* Maximum (signed) int value */
+#define LONG_MAX     0X7FFFFFFFL      /* max value for a long */
+#define LONG_MIN     (-LONG_MAX-1)    /* min value for a long */
+#define ULONG_MAX    0xFFFFFFFF       /* Maximum unsigned long value */
+#define CHAR_BIT     8                /* Number of bits in a char */
+
+// Maximum value for an object of type unsigned long long int.
+#define ULLONG_MAX  0xFFFFFFFFFFFFFFFFULL // 2^64 - 1
+// Maximum value for an object of type unsigned char.
+#define UCHAR_MAX   255  // 2^8 - 1
+
+//
+// Basic types mapping
+//
+typedef UINTN          size_t;
+typedef INTN           ssize_t;
+typedef INT32          time_t;
+typedef UINT8          __uint8_t;
+typedef UINT8          sa_family_t;
+typedef UINT32         uid_t;
+typedef UINT32         gid_t;
+typedef INT32          int32_t;
+typedef UINT32         uint32_t;
+typedef UINT16         uint16_t;
+typedef UINT8          uint8_t;
+typedef enum {false, true} bool;
+
+//
+// File operations are not required for EFI building,
+// so FILE is mapped to VOID * to pass build
+//
+typedef VOID  *FILE;
+
+//
+// Global variables
+//
+extern int  errno;
+extern FILE *stderr;
+
+//
+// Function prototypes of CRT Library routines
+//
+void           *malloc     (size_t);
+void           *realloc    (void *, size_t);
+void           *calloc     (size_t Num, size_t Size);
+void           free        (void *);
+void           *memset     (void *, int, size_t);
+int            memcmp      (const void *, const void *, size_t);
+int            isdigit     (int);
+int            isspace     (int);
+int            tolower     (int);
+int            isupper     (int);
+int            isxdigit    (int);
+int            isalnum     (int);
+void           *memcpy     (void *, const void *, size_t);
+void           *memset     (void *, int, size_t);
+void           *memchr     (const void *, int, size_t);
+int            memcmp      (const void *, const void *, size_t);
+void           *memmove    (void *, const void *, size_t);
+int            strcmp      (const char *, const char *);
+int            strncmp     (const char *, const char *, size_t);
+char           *strcpy     (char *, const char *);
+size_t         strlen      (const char *);
+char           *strcat     (char *, const char *);
+char           *strchr     (const char *, int);
+int            strcasecmp  (const char *, const char *);
+int            strncasecmp (const char *, const char *, size_t);
+char           *strncpy    (char *, size_t, const char *, size_t);
+int            strncmp     (const char *, const char *, size_t);
+char           *strrchr    (const char *, int);
+unsigned long  strtoul     (const char *, char **, int);
+char *         strstr      (const char *s1 , const char *s2);
+long           strtol      (const char *, char **, int);
+char           *strerror   (int);
+size_t         strspn      (const char *, const char *);
+char *         strdup      (const char *str);
+char *         strpbrk     (const char *s1, const char *s2);
+unsigned long long strtoull(const char * nptr, char ** endptr, int base);
+long long      strtoll     (const char * nptr, char ** endptr, int base);
+long           strtol      (const char * nptr, char ** endptr, int base);
+double         strtod      (const char * __restrict nptr, char ** __restrict endptr);
+size_t         strcspn     (const char *, const char *);
+int            printf      (const char *, ...);
+int            sscanf      (const char *, const char *, ...);
+FILE           *fopen      (const char *, const char *);
+size_t         fread       (void *, size_t, size_t, FILE *);
+size_t         fwrite      (const void *, size_t, size_t, FILE *);
+int            fclose      (FILE *);
+int            fprintf     (FILE *, const char *, ...);
+int            fgetc       (FILE * _File);
+uid_t          getuid      (void);
+uid_t          geteuid     (void);
+gid_t          getgid      (void);
+gid_t          getegid     (void);
+void           qsort       (void *, size_t, size_t, int (*)(const void *, const void *));
+char           *getenv     (const char *);
+#if defined(__GNUC__) && (__GNUC__ >= 2)
+void           abort       (void) __attribute__((__noreturn__));
+#else
+void           abort       (void);
+#endif
+int            toupper     (int);
+int            Digit2Val   (int);
+time_t         time        (time_t *);
+
+//
+// Macros that directly map functions to BaseLib, BaseMemoryLib, and DebugLib functions
+//
+#define strcmp                            AsciiStrCmp
+#define memcpy(dest,source,count)         CopyMem(dest,source,(UINTN)(count))
+#define memset(dest,ch,count)             SetMem(dest,(UINTN)(count),(UINT8)(ch))
+#define memchr(buf,ch,count)              ScanMem8(buf,(UINTN)(count),(UINT8)ch)
+#define memcmp(buf1,buf2,count)           (int)(CompareMem(buf1,buf2,(UINTN)(count)))
+#define memmove(dest,source,count)        CopyMem(dest,source,(UINTN)(count))
+#define strlen(str)                       (size_t)(AsciiStrnLenS(str,MAX_STRING_SIZE))
+#define strcpy(strDest,strSource)         AsciiStrCpyS(strDest,(strlen(strSource)+1),strSource)
+#define strncpy(strDest,strSource,count)  AsciiStrnCpyS(strDest,(UINTN)count,strSource,(UINTN)count)
+#define strncpys(strDest, DestLen, strSource,count)  AsciiStrnCpyS(strDest,DestLen,strSource,(UINTN)count)
+#define strcat(strDest,strSource)         AsciiStrCatS(strDest,(strlen(strSource)+strlen(strDest)+1),strSource)
+#define strchr(str,ch)                    ScanMem8((VOID *)(str),AsciiStrSize(str),(UINT8)ch)
+#define strncmp(string1,string2,count)    (int)(AsciiStrnCmp(string1,string2,(UINTN)(count)))
+#define strcasecmp(str1,str2)             (int)AsciiStriCmp(str1,str2)
+#define strstr(s1,s2)                     AsciiStrStr(s1,s2)
+#define sprintf(buf,...)                  AsciiSPrint(buf,MAX_STRING_SIZE,__VA_ARGS__)
+#define snprintf(buf,len,...)             AsciiSPrint(buf,len,__VA_ARGS__)
+#define vsnprintf(buf,len,format,marker)  AsciiVSPrint((buf),(len),(format),(marker))
+#define assert(expression)
+#define atoi(nptr)                        AsciiStrDecimalToUintn(nptr)
+#define fabs(x) (((x)<0.0)?(-x):(x))
+#define offsetof(type,member)             OFFSET_OF(type,member)
+
+#define EOF (-1)
+
+extern int  errno;
+
+#define ERANGE   34                /* 34   Result too large */
+
+#endif
diff --git a/RedfishPkg/Library/JsonLib/JsonLib.c b/RedfishPkg/Library/JsonLib/JsonLib.c
new file mode 100644
index 0000000000..3fa834add3
--- /dev/null
+++ b/RedfishPkg/Library/JsonLib/JsonLib.c
@@ -0,0 +1,960 @@
+/** @file
+  APIs for JSON operations.
+
+  Copyright (c) 2018 - 2019, Intel Corporation. All rights reserved.<BR>
+ (C) Copyright 2020 Hewlett Packard Enterprise Development LP<BR>
+
+    SPDX-License-Identifier: BSD-2-Clause-Patent
+**/
+
+#include <Library/JsonLib.h>
+#include "JsonUtilities.h"
+
+/**
+  The function is used to convert a NULL terminated UTF8 encoded string to a JSON
+  value. Only object and array represented strings can be converted successfully,
+  since they are the only valid root values of a JSON text for UEFI usage.
+
+  Real number and number with exponent part are not supportted by UEFI.
+
+  Caller needs to cleanup the root value by calling JsonValueFree().
+
+  @param[in]   Text             The NULL terminated UTF8 encoded string to convert
+
+  @retval      Array JSON value or object JSON value, or NULL when any error occurs.
+
+**/
+EDKII_JSON_VALUE
+EFIAPI
+TextToJson (
+  IN    CHAR8*    Text
+  )
+{
+  json_error_t    JsonError;
+
+  return (EDKII_JSON_VALUE) json_loads (Text, 0, &JsonError);
+}
+
+/**
+  The function is used to convert the JSON root value to a UTF8 encoded string which
+  is terminated by NULL, or return NULL on error.
+
+  Only array JSON value or object JSON value is valid for converting, and caller is
+  responsible for free converted string.
+
+  @param[in]   Json               The JSON value to be converted
+
+  @retval      The JSON value converted UTF8 string or NULL.
+
+**/
+CHAR8*
+EFIAPI
+JsonToText (
+  IN    EDKII_JSON_VALUE    Json
+  )
+{
+  if (!JsonValueIsArray (Json) && !JsonValueIsObject (Json)) {
+    return NULL;
+  }
+
+  return json_dumps ((json_t *) Json, 0);
+}
+
+/**
+  The function is used to initialize a JSON value which contains a new JSON array,
+  or NULL on error. Initially, the array is empty.
+
+  The reference count of this value will be set to 1, and caller needs to cleanup the
+  value by calling JsonValueFree().
+
+  More details for reference count strategy can refer to the API description for JsonValueFree().
+
+  @retval      The created JSON value which contains a JSON array or NULL.
+
+**/
+EDKII_JSON_VALUE
+EFIAPI
+JsonValueInitArray (
+  VOID
+  )
+{
+  return (EDKII_JSON_VALUE) json_array();
+}
+
+/**
+  The function is used to initialize a JSON value which contains a new JSON object,
+  or NULL on error. Initially, the object is empty.
+
+  The reference count of this value will be set to 1, and caller needs to cleanup the
+  value by calling JsonValueFree().
+
+  More details for reference count strategy can refer to the API description for JsonValueFree().
+
+  @retval      The created JSON value which contains a JSON object or NULL.
+
+**/
+EDKII_JSON_VALUE
+EFIAPI
+JsonValueInitObject (
+  VOID
+  )
+{
+  return (EDKII_JSON_VALUE) json_object();
+}
+
+/**
+  The function is used to initialize a JSON value which contains a new JSON string,
+  or NULL on error.
+
+  The input string must be NULL terminated Ascii format, non-Ascii characters will
+  be processed as an error. Unicode characters can also be represented by Ascii string
+  as the format: \u + 4 hexadecimal digits, like \u3E5A, or \u003F.
+
+  The reference count of this value will be set to 1, and caller needs to cleanup the
+  value by calling JsonValueFree().
+
+  More details for reference count strategy can refer to the API description for JsonValueFree().
+
+  @param[in]   String      The Ascii string to initialize to JSON value
+
+  @retval      The created JSON value which contains a JSON string or NULL. Select a
+               Getter API for a specific encoding format.
+
+**/
+EDKII_JSON_VALUE
+EFIAPI
+JsonValueInitAsciiString (
+  IN    CONST CHAR8    *String
+  )
+{
+  UINTN    Index;
+
+  if (String == NULL) {
+    return NULL;
+  }
+
+  Index = 0;
+  while (*(String + Index) != '\0') {
+    if (((*(String + Index)) & 0x80) != 0x00) {
+      return NULL;
+    }
+
+    Index ++;
+  }
+
+  return (EDKII_JSON_VALUE) json_string (String);
+}
+
+/**
+  The function is used to initialize a JSON value which contains a new JSON string,
+  or NULL on error.
+
+  The input must be a NULL terminated UCS2 format Unicode string.
+
+  The reference count of this value will be set to 1, and caller needs to cleanup the
+  value by calling JsonValueFree().
+
+  More details for reference count strategy can refer to the API description for JsonValueFree().
+
+  @param[in]   String      The Unicode string to initialize to JSON value
+
+  @retval      The created JSON value which contains a JSON string or NULL. Select a
+               Getter API for a specific encoding format.
+
+**/
+EDKII_JSON_VALUE
+EFIAPI
+JsonValueInitUnicodeString (
+  IN    CHAR16    *String
+  )
+{
+  EFI_STATUS    Status;
+  CHAR8         *Utf8Str;
+
+  if (String == NULL) {
+    return NULL;
+  }
+
+  Utf8Str = NULL;
+  Status  = UCS2StrToUTF8 (String, &Utf8Str);
+  if (EFI_ERROR (Status)) {
+    return NULL;
+  }
+
+  return (EDKII_JSON_VALUE) json_string (Utf8Str);
+}
+
+/**
+  The function is used to initialize a JSON value which contains a new JSON integer,
+  or NULL on error.
+
+  The reference count of this value will be set to 1, and caller needs to cleanup the
+  value by calling JsonValueFree().
+
+  More details for reference count strategy can refer to the API description for JsonValueFree().
+
+  @param[in]   Value       The integer to initialize to JSON value
+
+  @retval      The created JSON value which contains a JSON number or NULL.
+
+**/
+EDKII_JSON_VALUE
+EFIAPI
+JsonValueInitNumber (
+  IN    INT64    Value
+  )
+{
+  return (EDKII_JSON_VALUE) json_integer (Value);
+}
+
+/**
+  The function is used to initialize a JSON value which contains a new JSON boolean,
+  or NULL on error.
+
+  Boolean JSON value is kept as static value, and no need to do any cleanup work.
+
+  @param[in]   Value       The boolean value to initialize.
+
+  @retval      The created JSON value which contains a JSON boolean or NULL.
+
+**/
+EDKII_JSON_VALUE
+EFIAPI
+JsonValueInitBoolean (
+  IN    BOOLEAN    Value
+  )
+{
+  return (EDKII_JSON_VALUE) json_boolean (Value);
+}
+
+/**
+  The function is used to initialize a JSON value which contains a new JSON NULL,
+  or NULL on error.
+
+  NULL JSON value is kept as static value, and no need to do any cleanup work.
+
+  @retval      The created NULL JSON value.
+
+**/
+EDKII_JSON_VALUE
+EFIAPI
+JsonValueInitNull (
+  VOID
+  )
+{
+  return (EDKII_JSON_VALUE) json_null();
+}
+
+/**
+  The function is used to decrease the reference count of a JSON value by one, and once
+  this reference count drops to zero, the value is destroyed and it can no longer be used.
+  If this destroyed value is object type or array type, reference counts for all containing
+  JSON values will be decreased by 1. Boolean JSON value and NULL JSON value won't be destroyed
+  since they are static values kept in memory.
+
+  Reference Count Strategy: BaseJsonLib uses this strategy to track whether a value is still
+  in use or not. When a value is created, it's reference count is set to 1. If a reference to a
+  value is kept for use, its reference count is incremented, and when the value is no longer
+  needed, the reference count is decremented. When the reference count drops to zero, there are
+  no references left, and the value can be destroyed.
+
+  The given JSON value maybe NULL and not causing any problem. Just output the debug message
+  to inform caller the NULL value is passed in.
+
+  @param[in]   Json             The JSON value to be freed. json_decref may return without any
+                                changes if Json is NULL.
+
+**/
+VOID
+EFIAPI
+JsonValueFree (
+  IN    EDKII_JSON_VALUE    Json
+  )
+{
+  json_decref((json_t *)Json);
+}
+
+/**
+  The function is used to create a fresh copy of a JSON value, and all child values are deep
+  copied in a recursive fashion. It should be called when this JSON value might be modified
+  in later use, but the original still wants to be used in somewhere else.
+
+  Reference counts of the returned root JSON value and all child values will be set to 1, and
+  caller needs to cleanup the root value by calling JsonValueFree().
+
+  * Note: Since this function performs a copy from bottom to up, too many calls may cause some
+  performance issues, user should avoid unnecessary calls to this function unless it is really
+  needed.
+
+  @param[in]   Json             The JSON value to be cloned.
+
+  @retval      Return the cloned JSON value, or NULL on error.
+
+**/
+EDKII_JSON_VALUE
+EFIAPI
+JsonValueClone (
+  IN    EDKII_JSON_VALUE    Json
+  )
+{
+  return (EDKII_JSON_VALUE) json_deep_copy ((json_t *) Json);
+}
+
+/**
+  The function is used to return if the provided JSON value contains a JSON array.
+
+  @param[in]   Json             The provided JSON value.
+
+  @retval      TRUE             The JSON value contains a JSON array.
+  @retval      FALSE            The JSON value doesn't contain a JSON array.
+
+**/
+BOOLEAN
+EFIAPI
+JsonValueIsArray (
+  IN    EDKII_JSON_VALUE    Json
+  )
+{
+  return json_is_array ((json_t *) Json);
+}
+
+/**
+  The function is used to return if the provided JSON value contains a JSON object.
+
+  @param[in]   Json             The provided JSON value.
+
+  @retval      TRUE             The JSON value contains a JSON object.
+  @retval      FALSE            The JSON value doesn't contain a JSON object.
+
+**/
+BOOLEAN
+EFIAPI
+JsonValueIsObject (
+  IN    EDKII_JSON_VALUE    Json
+  )
+{
+  return json_is_object ((json_t *) Json);
+}
+
+/**
+  The function is used to return if the provided JSON Value contains a string, Ascii or
+  Unicode format is not differentiated.
+
+  @param[in]   Json             The provided JSON value.
+
+  @retval      TRUE             The JSON value contains a JSON string.
+  @retval      FALSE            The JSON value doesn't contain a JSON string.
+
+**/
+BOOLEAN
+EFIAPI
+JsonValueIsString (
+  IN    EDKII_JSON_VALUE    Json
+  )
+{
+  return json_is_string ((json_t *) Json);
+}
+
+/**
+  The function is used to return if the provided JSON value contains a JSON number.
+
+  @param[in]   Json             The provided JSON value.
+
+  @retval      TRUE             The JSON value is contains JSON number.
+  @retval      FALSE            The JSON value doesn't contain a JSON number.
+
+**/
+BOOLEAN
+EFIAPI
+JsonValueIsNumber (
+  IN    EDKII_JSON_VALUE    Json
+  )
+{
+  return json_is_integer ((json_t *) Json);
+}
+
+/**
+  The function is used to return if the provided JSON value contains a JSON boolean.
+
+  @param[in]   Json             The provided JSON value.
+
+  @retval      TRUE             The JSON value contains a JSON boolean.
+  @retval      FALSE            The JSON value doesn't contain a JSON boolean.
+
+**/
+BOOLEAN
+EFIAPI
+JsonValueIsBoolean (
+  IN    EDKII_JSON_VALUE    Json
+  )
+{
+  return json_is_boolean ((json_t *) Json);
+}
+
+/**
+  The function is used to return if the provided JSON value contains a JSON NULL.
+
+  @param[in]   Json             The provided JSON value.
+
+  @retval      TRUE             The JSON value contains a JSON NULL.
+  @retval      FALSE            The JSON value doesn't contain a JSON NULL.
+
+**/
+BOOLEAN
+EFIAPI
+JsonValueIsNull (
+  IN    EDKII_JSON_VALUE    Json
+  )
+{
+  return json_is_null ((json_t *) Json);
+}
+
+/**
+  The function is used to retrieve the associated array in an array type JSON value.
+
+  Any changes to the returned array will impact the original JSON value.
+
+  @param[in]   Json             The provided JSON value.
+
+  @retval      Return the associated array in JSON value or NULL.
+
+**/
+EDKII_JSON_ARRAY
+EFIAPI
+JsonValueGetArray (
+  IN    EDKII_JSON_VALUE    Json
+  )
+{
+  if (Json == NULL || !JsonValueIsArray (Json)) {
+    return NULL;
+  }
+
+  return (EDKII_JSON_ARRAY) Json;
+}
+
+/**
+  The function is used to retrieve the associated object in an object type JSON value.
+
+  Any changes to the returned object will impact the original JSON value.
+
+  @param[in]   Json             The provided JSON value.
+
+  @retval      Return the associated object in JSON value or NULL.
+
+**/
+EDKII_JSON_OBJECT
+EFIAPI
+JsonValueGetObject (
+  IN    EDKII_JSON_VALUE    Json
+  )
+{
+  if (Json == NULL || !JsonValueIsObject (Json)) {
+    return NULL;
+  }
+
+  return (EDKII_JSON_OBJECT) Json;
+}
+
+/**
+  The function is used to retrieve the associated Ascii string in a string type JSON value.
+
+  Any changes to the returned string will impact the original JSON value.
+
+  @param[in]   Json             The provided JSON value.
+
+  @retval      Return the associated Ascii string in JSON value or NULL.
+
+**/
+CHAR8*
+EFIAPI
+JsonValueGetAsciiString (
+  IN    EDKII_JSON_VALUE    Json
+  )
+{
+  CHAR8          *AsciiStr;
+  UINTN          Index;
+
+  AsciiStr = (CHAR8 *)  ((json_t *) Json);
+  if (AsciiStr == NULL) {
+    return NULL;
+  }
+
+  Index = 0;
+  while (*(AsciiStr + Index) != '\0') {
+    if (((*(AsciiStr + Index)) & 0x80) != 0x00) {
+      return NULL;
+    }
+
+    Index ++;
+  }
+
+  return AsciiStr;
+}
+
+/**
+  The function is used to retrieve the associated Unicode string in a string type JSON value.
+
+  Caller can do any changes to the returned string without any impact to the original JSON
+  value, and caller needs to free the returned string.
+
+  @param[in]   Json             The provided JSON value.
+
+  @retval      Return the associated Unicode string in JSON value or NULL.
+
+**/
+CHAR16*
+EFIAPI
+JsonValueGetUnicodeString (
+  IN    EDKII_JSON_VALUE    Json
+  )
+{
+  EFI_STATUS     Status;
+  CONST CHAR8    *Utf8Str;
+  CHAR16         *Ucs2Str;
+
+  Utf8Str = json_string_value ((json_t *) Json);
+  if (Utf8Str == NULL) {
+    return NULL;
+  }
+
+  Status = UTF8StrToUCS2 ((CHAR8*)Utf8Str, &Ucs2Str);
+  if (EFI_ERROR (Status)) {
+    return NULL;
+  }
+
+  return Ucs2Str;
+}
+
+/**
+  The function is used to retrieve the associated integer in a number type JSON value.
+
+  The input JSON value should not be NULL or contain no JSON number, otherwise it will
+  ASSERT() and return 0.
+
+  @param[in]   Json             The provided JSON value.
+
+  @retval      Return the associated number in JSON value.
+
+**/
+INT64
+EFIAPI
+JsonValueGetNumber (
+  IN    EDKII_JSON_VALUE    Json
+  )
+{
+  ASSERT (Json != NULL && JsonValueIsNumber (Json));
+  if (Json == NULL || !JsonValueIsNumber (Json)) {
+    return 0;
+  }
+
+  return json_integer_value ((json_t *) Json);
+}
+
+/**
+  The function is used to retrieve the associated boolean in a boolean type JSON value.
+
+  The input JSON value should not be NULL or contain no JSON boolean, otherwise it will
+  ASSERT() and return FALSE.
+
+  @param[in]   Json             The provided JSON value.
+
+  @retval      Return the associated value of JSON boolean.
+
+**/
+BOOLEAN
+EFIAPI
+JsonValueGetBoolean (
+  IN    EDKII_JSON_VALUE    Json
+  )
+{
+  ASSERT (Json != NULL && JsonValueIsBoolean (Json));
+  if (Json == NULL || !JsonValueIsBoolean (Json)) {
+    return FALSE;
+  }
+
+  return json_is_true ((json_t *) Json);
+}
+
+/**
+  The function is used to retrieve the associated string in a string type JSON value.
+
+  Any changes to the returned string will impact the original JSON value.
+
+  @param[in]   Json The provided JSON value.
+
+  @retval      Return the associated Ascii string in JSON value or NULL.
+
+**/
+CONST CHAR8*
+EFIAPI
+JsonValueGetString (
+  IN    EDKII_JSON_VALUE    Json
+  )
+{
+  return json_string_value ((const json_t *)Json);
+}
+
+/**
+  The function is used to get the number of elements in a JSON object, or 0 if it is NULL or
+  not a JSON object.
+
+  @param[in]   JsonObject              The provided JSON object.
+
+  @retval      Return the number of elements in this JSON object or 0.
+
+**/
+UINTN
+EFIAPI
+JsonObjectSize (
+  IN    EDKII_JSON_OBJECT    JsonObject
+  )
+{
+  return json_object_size ((json_t *) JsonObject);
+}
+
+/**
+  The function is used to enumerate all keys in a JSON object.
+
+  Caller should be responsible to free the returned key array refference. But contained keys
+  are read only and must not be modified or freed.
+
+  @param[in]   JsonObj                The provided JSON object for enumeration.
+  @param[out]  KeyCount               The count of keys in this JSON object.
+
+  @retval      Return an array of the enumerated keys in this JSON object or NULL.
+
+**/
+CHAR8**
+JsonObjectGetKeys (
+  IN    EDKII_JSON_OBJECT    JsonObj,
+  OUT   UINTN                *KeyCount
+  )
+{
+
+  UINTN               Index;
+  CONST CHAR8         **KeyArray;
+  CONST CHAR8         *Key;
+  EDKII_JSON_VALUE    Value;
+
+  if (JsonObj == NULL || KeyCount == NULL) {
+    return NULL;
+  }
+
+  Index = 0;
+  json_object_foreach(JsonObj, Key, Value) {
+    Index ++;
+  }
+  if (Index == 0) {
+    *KeyCount = 0;
+    return NULL;
+  }
+
+  *KeyCount = Index;
+  KeyArray = (CONST CHAR8 **) AllocateZeroPool (*KeyCount * sizeof (CHAR8 *));
+  if (KeyArray == NULL) {
+    return NULL;
+  }
+
+  Key   = NULL;
+  Value = NULL;
+  Index = 0;
+  json_object_foreach((json_t *) JsonObj, Key, Value) {
+    KeyArray[Index] = Key;
+    Index ++;
+  }
+
+  return (CHAR8 **)KeyArray;
+}
+
+/**
+  The function is used to get a JSON value corresponding to the input key from a JSON object.
+
+  It only returns a reference to this value and any changes on this value will impact the
+  original JSON object. If that is not expected, please call JsonValueClone() to clone it to
+  use.
+
+  Input key must be a valid NULL terminated UTF8 encoded string. NULL will be returned when
+  Key-Value is not found in this JSON object.
+
+  @param[in]   JsonObj           The provided JSON object.
+  @param[in]   Key               The key of the JSON value to be retrieved.
+
+  @retval      Return the corresponding JSON value to key, or NULL on error.
+
+**/
+EDKII_JSON_VALUE
+EFIAPI
+JsonObjectGetValue (
+  IN    CONST EDKII_JSON_OBJECT    JsonObj,
+  IN    CONST CHAR8                *Key
+  )
+{
+  return (EDKII_JSON_VALUE) json_object_get ((const json_t *)JsonObj, (const char *)Key);
+}
+
+/**
+  The function is used to set a JSON value corresponding to the input key from a JSON object,
+  and the reference count of this value will be increased by 1.
+
+  Input key must be a valid NULL terminated UTF8 encoded string. If there already is a value for
+  this key, this key will be assigned to the new JSON value. The old JSON value will be removed
+  from this object and thus its' reference count will be decreased by 1.
+
+  More details for reference count strategy can refer to the API description for JsonValueFree().
+
+  @param[in]   JsonObj                The provided JSON object.
+  @param[in]   Key                    The key of the JSON value to be set.
+  @param[in]   Json                   The JSON value to set to this JSON object mapped by key.
+
+  @retval      EFI_ABORTED            Some error occur and operation aborted.
+  @retval      EFI_SUCCESS            The JSON value has been set to this JSON object.
+
+**/
+EFI_STATUS
+EFIAPI
+JsonObjectSetValue (
+  IN    EDKII_JSON_OBJECT    JsonObj,
+  IN    CONST CHAR8          *Key,
+  IN    EDKII_JSON_VALUE     Json
+  )
+{
+  if (json_object_set ((json_t *) JsonObj, Key, (json_t *) Json) != 0) {
+    return EFI_ABORTED;
+  } else {
+    return EFI_SUCCESS;
+  }
+}
+
+/**
+  The function is used to get the number of elements in a JSON array, or 0 if it is NULL or
+  not a JSON array.
+
+  @param[in]   JsonArray              The provided JSON array.
+
+  @retval      Return the number of elements in this JSON array or 0.
+
+**/
+UINTN
+EFIAPI
+JsonArrayCount (
+  IN    EDKII_JSON_ARRAY    JsonArray
+  )
+{
+  return json_array_size ((json_t *) JsonArray);
+}
+
+/**
+  The function is used to return the JSON value in the array at position index. The valid range
+  for this index is from 0 to the return value of JsonArrayCount() minus 1.
+
+  It only returns a reference to this value and any changes on this value will impact the
+  original JSON object. If that is not expected, please call JsonValueClone() to clone it to
+  use.
+
+  If this array is NULL or not a JSON array, or if index is out of range, NULL will be returned.
+
+  @param[in]   JsonArray         The provided JSON Array.
+
+  @retval      Return the JSON value located in the Index position or NULL.
+
+**/
+EDKII_JSON_VALUE
+EFIAPI
+JsonArrayGetValue (
+  IN    EDKII_JSON_ARRAY    JsonArray,
+  IN    UINTN               Index
+  )
+{
+  return (EDKII_JSON_VALUE) json_array_get ((json_t *) JsonArray, Index);
+}
+
+/**
+  The function is used to append a JSON value to the end of the JSON array, and grow the size of
+  array by 1. The reference count of this value will be increased by 1.
+
+  More details for reference count strategy can refer to the API description for JsonValueFree().
+
+  @param[in]   JsonArray              The provided JSON object.
+  @param[in]   Json                   The JSON value to append.
+
+  @retval      EFI_ABORTED            Some error occur and operation aborted.
+  @retval      EFI_SUCCESS            JSON value has been appended to the end of the JSON array.
+
+**/
+EFI_STATUS
+EFIAPI
+JsonArrayAppendValue (
+  IN    EDKII_JSON_ARRAY    JsonArray,
+  IN    EDKII_JSON_VALUE    Json
+  )
+{
+  if (json_array_append ((json_t *) JsonArray, (json_t *) Json) != 0) {
+    return EFI_ABORTED;
+  } else {
+    return EFI_SUCCESS;
+  }
+}
+
+/**
+  The function is used to remove a JSON value at position index, shifting the elements after index
+  one position towards the start of the array. The reference count of this value will be decreased
+  by 1.
+
+  More details for reference count strategy can refer to the API description for JsonValueFree().
+
+  @param[in]   JsonArray              The provided JSON array.
+  @param[in]   Index                  The Index position before removement.
+
+  @retval      EFI_ABORTED            Some error occur and operation aborted.
+  @retval      EFI_SUCCESS            The JSON array has been removed at position index.
+
+**/
+EFI_STATUS
+EFIAPI
+JsonArrayRemoveValue (
+  IN    EDKII_JSON_ARRAY    JsonArray,
+  IN    UINTN               Index
+  )
+{
+  if (json_array_remove ((json_t *) JsonArray, Index) != 0) {
+    return EFI_ABORTED;
+  } else {
+    return EFI_SUCCESS;
+  }
+}
+
+/**
+  Dump JSON to a buffer.
+
+  @param[in]   JsonValue       The provided JSON array.
+  @param[in]   Flags           The Index position before removement.
+
+  @retval      NULL            Dump fail if NULL returned, otherwise the buffer
+                               contain JSON paylaod in ASCII string.
+**/
+CHAR8 *
+EFIAPI
+JsonDumpString (
+  IN    EDKII_JSON_ARRAY    JsonValue,
+  IN    UINTN               Flags
+  )
+{
+    if (JsonValue == NULL) {
+      return NULL;
+    }
+    return json_dumps((json_t *)JsonValue, Flags);
+}
+
+/**
+  Load JSON from a buffer.
+
+  @param[in]   Buffer        Bufffer to the JSON payload
+  @param[in]   BufferLen     Length of the buffer
+  @param[in]   Flags         Flag of loading JSON buffer
+  @param[in]   Error         Pointer to error structure
+
+  @retval      EDKII_JSON_VALUE  NULL means fail to load JSON payload.
+**/
+EDKII_JSON_VALUE
+EFIAPI
+JsonLoadBuffer (
+  IN    CONST CHAR8       *Buffer,
+  IN    UINTN             BufferLen,
+  IN    UINTN             Flags,
+  IN    EDKII_JSON_ERROR  *Error
+  )
+{
+  return json_loadb(Buffer, BufferLen, Flags, (json_error_t *)Error);
+}
+
+/**
+  Decrease reference.
+
+  @param[in]   JsonValue      JSON value
+**/
+VOID
+EFIAPI
+JsonDecreaseReference (
+  IN EDKII_JSON_VALUE JsonValue
+  )
+{
+  json_decref (JsonValue);
+}
+
+/**
+  Increase reference.
+
+  @param[in]   JsonValue      JSON value
+  @retval      EDKII_JSON_VALUE of itself
+**/
+EDKII_JSON_VALUE
+EFIAPI
+JsonIncreaseReference (
+  IN EDKII_JSON_VALUE JsonValue
+  )
+{
+  return json_incref (JsonValue);
+}
+
+/**
+  Returns an opaque iterator which can be used to iterate over all key-value pairs
+  in object, or NULL if object is empty.
+
+  @param[in]   JsonValue      JSON value
+  @retval      Iterator pointer
+**/
+VOID *
+EFIAPI
+JsonObjectIterator (
+  IN EDKII_JSON_VALUE JsonValue
+  )
+{
+  return json_object_iter (JsonValue);
+}
+
+/**
+  Extract the associated value from iterator.
+
+  @param[in]   Iterator   Iterator pointer
+  @retval      EDKII_JSON_VALUE
+**/
+EDKII_JSON_VALUE
+EFIAPI
+JsonObjectIteratorValue (
+  IN VOID *Iterator
+  )
+{
+  return json_object_iter_value(Iterator);
+}
+
+/**
+  Returns an iterator pointing to the next key-value pair in object after iter,
+  or NULL if the whole object has been iterated through.
+
+  @param[in]   JsonValue  JSON value
+  @param[in]   Iterator   Iterator pointer
+  @retval      Iterator pointer
+**/
+VOID *
+JsonObjectIteratorNext (
+  IN EDKII_JSON_VALUE JsonValue,
+  IN VOID             *Iterator
+  )
+{
+  return json_object_iter_next(JsonValue, Iterator);
+}
+
+/**
+  Returns the json type of this json value.
+
+  @param[in]   JsonValue  JSON value
+  @retval      JSON type returned
+**/
+EDKII_JSON_TYPE
+EFIAPI
+JsonGetType (
+  IN EDKII_JSON_VALUE JsonValue
+  )
+{
+  return ((json_t *)JsonValue)->type;
+}
diff --git a/RedfishPkg/Library/JsonLib/JsonLib.inf b/RedfishPkg/Library/JsonLib/JsonLib.inf
new file mode 100644
index 0000000000..16df2ae183
--- /dev/null
+++ b/RedfishPkg/Library/JsonLib/JsonLib.inf
@@ -0,0 +1,103 @@
+## @file
+# Thirty party Jansson library for JSON operations.
+#
+# Copyright (c) 2019, Intel Corporation. All rights reserved.<BR>
+# (C) Copyright 2020 Hewlett Packard Enterprise Development LP<BR>
+#
+#    SPDX-License-Identifier: BSD-2-Clause-Patent
+#
+##
+
+[Defines]
+  INF_VERSION                    = 0x0001001b
+  BASE_NAME                      = JsonLib
+  FILE_GUID                      = F5E36815-305A-4C5A-9D75-4F2149E45255
+  MODULE_TYPE                    = UEFI_DRIVER
+  VERSION_STRING                 = 1.0
+  LIBRARY_CLASS                  = JsonLib | DXE_DRIVER DXE_RUNTIME_DRIVER UEFI_APPLICATION UEFI_DRIVER
+
+#
+#  VALID_ARCHITECTURES           = IA32 X64 ARM AARCH64 RISCV64
+#
+
+[Sources]
+  #
+  # Below are the source code of third
+  # party jansson library.
+  #
+  jansson/src/dump.c
+  jansson/src/error.c
+  jansson/src/hashtable.c
+  jansson/src/hashtable_seed.c
+  jansson/src/memory.c
+  jansson/src/pack_unpack.c
+  jansson/src/strbuffer.c
+  jansson/src/strconv.c
+  jansson/src/utf.c
+  jansson/src/value.c
+  jansson/src/version.c
+  #
+  # Below are the source of edk2 JsonLib.
+  #
+  JsonLib.c
+  JsonUtilities.c
+  JsonUtilities.h
+  JanssonCrtLibSupport.c
+  JanssonCrtLibSupport.h
+  jansson_config.h
+  jansson_private_config.h
+  sys/time.h
+  sys/types.h
+  assert.h
+  errno.h
+  limits.h
+  math.h
+  stdarg.h
+  stddef.h
+  stdio.h
+  stdlib.h
+  string.h
+  time.h
+  #
+  # Below is the source code override to fix the build issue.
+  # Add code in load.c to conditionally use stdin according
+  # to HAVE_UNISTD_H macro. The PR is submitted to jansson
+  # open source community.
+  # https://github.com/akheron/jansson/pull/558
+  #
+  load.c
+
+[Packages]
+  MdePkg/MdePkg.dec
+  MdeModulePkg/MdeModulePkg.dec
+  RedfishPkg/RedfishPkg.dec
+
+[LibraryClasses]
+  UefiLib
+  BaseLib
+  BaseMemoryLib
+  MemoryAllocationLib
+  UefiRuntimeServicesTableLib
+  DebugLib
+  PrintLib
+
+[BuildOptions]
+  #
+  # Disables the following Visual Studio compiler warnings
+  # so we do not break the build with /WX option:
+  #   C4090: 'function' : different 'const' qualifiers
+  #   C4244: conversion from type1 to type2, possible loss of data
+  #   C4702: unreachable code
+  #   C4706: assignment within conditional expression
+  #   C4456: declaration hides previous local declaration
+  #   C4334: 32-bit shift implicitly converted to 64-bit
+  #   C4204: nonstandard extension used: non-constant aggregate initializer
+  #   C4267: 'var' : conversion from 'size_t' to 'type', possible loss of data
+  #
+  # Define macro HAVE_CONFIG_H to include jansson_private_config.h to build.
+  # Undefined _WIN32, WIN64, _MSC_VER macros
+  # On GCC, no error on the unused-function and unused-but-set-variable.
+  #
+  MSFT:*_*_*_CC_FLAGS = /wd4204 /wd4267 /wd4702 /wd4706 /wd4244 /wd4090 /wd4456 /wd4334 /DHAVE_CONFIG_H=1 /U_WIN32 /UWIN64 /U_MSC_VER
+  GCC:*_*_*_CC_FLAGS = -Wno-unused-function -Wno-unused-but-set-variable
+
diff --git a/RedfishPkg/Library/JsonLib/JsonUtilities.c b/RedfishPkg/Library/JsonLib/JsonUtilities.c
new file mode 100644
index 0000000000..f84a133219
--- /dev/null
+++ b/RedfishPkg/Library/JsonLib/JsonUtilities.c
@@ -0,0 +1,417 @@
+/** @file
+  Utility functions for JSON operations.
+
+  Copyright (c) 2018 - 2019, Intel Corporation. All rights reserved.<BR>
+ (C) Copyright 2020 Hewlett Packard Enterprise Development LP<BR>
+
+    SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#include "JsonUtilities.h"
+
+/**
+  Since each UCS2 character can be represented by 1-3 UTF8 encoded characters,
+  this function is used to retrieve the UTF8 encoding size for a UCS2 character.
+
+  @param[in]   Utf8Buffer       The buffer for UTF8 encoded data.
+
+  @retval      Return the size of UTF8 encoding string or 0 if it is not for
+               UCS2 format.
+
+**/
+UINT8
+GetUTF8SizeForUCS2 (
+  IN    CHAR8      *Utf8Buffer
+  )
+{
+  CHAR8    TempChar;
+  UINT8    Utf8Size;
+
+  ASSERT (Utf8Buffer != NULL);
+
+  TempChar = *Utf8Buffer;
+  if ((TempChar & 0xF0) == 0xF0) {
+
+    //
+    // This format is not for UCS2.
+    //
+    return 0;
+  }
+
+  Utf8Size = 1;
+  if ((TempChar & 0x80) == 0x80) {
+    if ((TempChar & 0xC0) == 0xC0) {
+
+      Utf8Size ++;
+      if ((TempChar & 0xE0) == 0xE0) {
+
+        Utf8Size ++;
+      }
+    }
+  }
+
+  return Utf8Size;
+}
+
+/**
+  Since each UCS2 character can be represented by the format: \uXXXX, this function
+  is used to retrieve the UCS2 character from a Unicode format.
+  Call MUST make sure there are at least 6 Bytes in the input UTF8 buffer.
+
+  @param[in]    Utf8Buffer             The buffer for UTF8 encoded data.
+  @param[out]   Ucs2Char               The converted UCS2 character.
+
+  @retval       EFI_INVALID_PARAMETER  Non-Ascii characters found in the hexadecimal
+                                       digits string, and can't be converted to a UCS2
+                                       character.
+  @retval       EFI_SUCCESS            The UCS2 character has been retrieved.
+
+**/
+EFI_STATUS
+GetUCS2CharByFormat (
+  IN    CHAR8      *Utf8Buffer,
+  OUT   CHAR16     *Ucs2Char
+  )
+{
+  UINT8     Num1;
+  UINT8     Num2;
+  UINT8     Index;
+  CHAR8     Ucs2CharFormat[JSON_UNICODE_FORMAT_CHAR_SIZE];  /// two Hexadecimal digits Ascii string, like "3F"
+
+  for (Index = 0; Index < 4; Index ++) {
+    if ((*(Utf8Buffer + 2 + Index) & 0x80) != 0x00) {
+      return EFI_INVALID_PARAMETER;
+    }
+  }
+
+  ZeroMem (Ucs2CharFormat, JSON_UNICODE_FORMAT_CHAR_SIZE);
+
+  //
+  // Get the First Number, Offset is 2
+  //
+  CopyMem (Ucs2CharFormat, Utf8Buffer + 2, JSON_UNICODE_FORMAT_CHAR_LEN);
+  Num1 = (UINT8) AsciiStrHexToUintn (Ucs2CharFormat);
+
+  //
+  // Get the Second Number, Offset is 4
+  //
+  CopyMem (Ucs2CharFormat, Utf8Buffer + 4, JSON_UNICODE_FORMAT_CHAR_LEN);
+  Num2 = (UINT8) AsciiStrHexToUintn (Ucs2CharFormat);
+
+  //
+  // Ucs2Char is Little-Endian
+  //
+  *((CHAR8 *) Ucs2Char)        = Num2;
+  *(((CHAR8 *) Ucs2Char) + 1) = Num1;
+
+  return EFI_SUCCESS;
+}
+
+/**
+  Convert a UCS2 character to UTF8 encoding string.
+
+  @param[in]    Ucs2Char               The provided UCS2 character.
+  @param[out]   Utf8Buffer             The converted UTF8 encoded data.
+
+  @retval      Return the size of UTF8 encoding data for this UCS2 character.
+
+**/
+UINT8
+UCS2CharToUTF8 (
+  IN  CHAR16     Ucs2Char,
+  OUT CHAR8      *Utf8Buffer
+  )
+{
+  UINT16    Ucs2Number;
+
+  ASSERT (Utf8Buffer != NULL);
+
+  Ucs2Number = (UINT16) Ucs2Char;
+  if (Ucs2Number <= 0x007F) {
+
+    //
+    // UTF8 format: 0xxxxxxx
+    //
+    *Utf8Buffer = Ucs2Char & 0x7F;
+    return 1;
+
+  } else if (Ucs2Number >= 0x0080 && Ucs2Number <= 0x07FF) {
+
+    //
+    // UTF8 format: 110xxxxx 10xxxxxx
+    //
+    *(Utf8Buffer + 1) = (Ucs2Char & 0x3F) | 0x80;
+    *Utf8Buffer       = ((Ucs2Char >> 6) & 0x1F) | 0xC0;
+    return 2;
+
+  } else {  /// Ucs2Number >= 0x0800 && Ucs2Number <= 0xFFFF
+
+    //
+    // UTF8 format: 1110xxxx 10xxxxxx 10xxxxxx
+    //
+    *(Utf8Buffer + 2) = (Ucs2Char & 0x3F) | 0x80;
+    *(Utf8Buffer + 1) = ((Ucs2Char >> 6) & 0x3F) | 0x80;
+    *Utf8Buffer       = ((Ucs2Char >> 12) & 0x0F) | 0xE0;
+    return 3;
+  }
+}
+
+/**
+  Convert a UTF8 encoded data to a UCS2 character.
+
+  @param[in]    Utf8Buffer             The provided UTF8 encoded data.
+  @param[out]   Ucs2Char               The converted UCS2 character.
+
+  @retval       EFI_INVALID_PARAMETER  The UTF8 encoded string is not valid or
+                                       not for UCS2 character.
+  @retval       EFI_SUCCESS            The converted UCS2 character.
+
+**/
+EFI_STATUS
+UTF8ToUCS2Char (
+  IN   CHAR8      *Utf8Buffer,
+  OUT  CHAR16     *Ucs2Char
+  )
+{
+  UINT8    Utf8Size;
+  CHAR8    *Ucs2Buffer;
+  CHAR8    TempChar1;
+  CHAR8    TempChar2;
+  CHAR8    TempChar3;
+
+  ASSERT (Utf8Buffer != NULL && Ucs2Char != NULL);
+  ZeroMem (Ucs2Char, sizeof (CHAR16));
+  Ucs2Buffer = (CHAR8 *) Ucs2Char;
+
+  Utf8Size = GetUTF8SizeForUCS2 (Utf8Buffer);
+  switch (Utf8Size) {
+
+    case 1:
+
+      //
+      // UTF8 format: 0xxxxxxx
+      //
+      TempChar1 = *Utf8Buffer;
+      if ((TempChar1 & 0x80) != 0x00) {
+        return EFI_INVALID_PARAMETER;
+      }
+
+      *Ucs2Buffer       = TempChar1;
+      *(Ucs2Buffer + 1) = 0;
+      break;
+
+    case 2:
+
+      //
+      // UTF8 format: 110xxxxx 10xxxxxx
+      //
+      TempChar1 = *Utf8Buffer;
+      if ((TempChar1 & 0xE0) != 0xC0) {
+        return EFI_INVALID_PARAMETER;
+      }
+
+      TempChar2 = *(Utf8Buffer + 1);
+      if ((TempChar2 & 0xC0) != 0x80) {
+        return EFI_INVALID_PARAMETER;
+      }
+
+      *Ucs2Buffer       = (TempChar1 << 6) + (TempChar2 & 0x3F);
+      *(Ucs2Buffer + 1) = (TempChar1 >> 2) & 0x07;
+      break;
+
+    case 3:
+
+      //
+      // UTF8 format: 1110xxxx 10xxxxxx 10xxxxxx
+      //
+      TempChar1 = *Utf8Buffer;
+      if ((TempChar1 & 0xF0) != 0xE0) {
+        return EFI_INVALID_PARAMETER;
+      }
+
+      TempChar2 = *(Utf8Buffer + 1);
+      if ((TempChar2 & 0xC0) != 0x80) {
+        return EFI_INVALID_PARAMETER;
+      }
+
+      TempChar3 = *(Utf8Buffer + 2);
+      if ((TempChar3 & 0xC0) != 0x80) {
+        return EFI_INVALID_PARAMETER;
+      }
+
+      *Ucs2Buffer       = (TempChar2 << 6) + (TempChar3 & 0x3F);
+      *(Ucs2Buffer + 1) = (TempChar1 << 4) + ((TempChar2 >> 2) & 0x0F);
+
+      break;
+
+    default:
+
+      return EFI_INVALID_PARAMETER;
+  }
+
+  return EFI_SUCCESS;
+}
+
+/**
+  Convert a UCS2 string to a UTF8 encoded string.
+
+  @param[in]    Ucs2Str                The provided UCS2 string.
+  @param[out]   Utf8StrAddr            The converted UTF8 string address. Caller
+                                       is responsible for Free this string.
+
+  @retval       EFI_INVALID_PARAMETER  One or more parameters are invalid.
+  @retval       EFI_OUT_OF_RESOURCES   System runs out of resources.
+  @retval       EFI_SUCCESS            The UTF8 encoded string has been converted.
+
+**/
+EFI_STATUS
+UCS2StrToUTF8 (
+  IN  CHAR16     *Ucs2Str,
+  OUT CHAR8      **Utf8StrAddr
+  )
+{
+  UINTN    Ucs2StrIndex;
+  UINTN    Ucs2StrLength;
+  CHAR8    *Utf8Str;
+  UINTN    Utf8StrLength;
+  UINTN    Utf8StrIndex;
+  CHAR8    Utf8Buffer[UTF8_BUFFER_FOR_UCS2_MAX_SIZE];
+  UINT8    Utf8BufferSize;
+
+  if (Ucs2Str == NULL || Utf8StrAddr == NULL) {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  Ucs2StrLength = StrLen (Ucs2Str);
+  Utf8StrLength = 0;
+
+  for (Ucs2StrIndex = 0; Ucs2StrIndex < Ucs2StrLength; Ucs2StrIndex ++) {
+
+    ZeroMem (Utf8Buffer, sizeof (Utf8Buffer));
+    Utf8BufferSize = UCS2CharToUTF8 (Ucs2Str[Ucs2StrIndex], Utf8Buffer);
+    Utf8StrLength += Utf8BufferSize;
+  }
+
+  Utf8Str = AllocateZeroPool (Utf8StrLength + 1);
+  if (Utf8Str == NULL) {
+    return EFI_OUT_OF_RESOURCES;
+  }
+
+  Utf8StrIndex = 0;
+  for (Ucs2StrIndex = 0; Ucs2StrIndex < Ucs2StrLength; Ucs2StrIndex ++) {
+
+    ZeroMem (Utf8Buffer, sizeof (Utf8Buffer));
+    Utf8BufferSize = UCS2CharToUTF8 (Ucs2Str[Ucs2StrIndex], Utf8Buffer);
+
+    CopyMem (Utf8Str + Utf8StrIndex, Utf8Buffer, Utf8BufferSize);
+    Utf8StrIndex += Utf8BufferSize;
+  }
+
+  Utf8Str[Utf8StrIndex] = '\0';
+  *Utf8StrAddr = Utf8Str;
+
+  return EFI_SUCCESS;
+}
+
+/**
+  Convert a UTF8 encoded string to a UCS2 string.
+
+  @param[in]    Utf8Str                The provided UTF8 encoded string.
+  @param[out]   Ucs2StrAddr            The converted UCS2 string address. Caller
+                                       is responsible for Free this string.
+
+  @retval       EFI_INVALID_PARAMETER  The UTF8 encoded string is not valid to
+                                       convert to UCS2 string.
+                                       One or more parameters are invalid.
+  @retval       EFI_OUT_OF_RESOURCES   System runs out of resources.
+  @retval       EFI_SUCCESS            The UCS2 string has been converted.
+
+**/
+EFI_STATUS
+UTF8StrToUCS2 (
+  IN  CHAR8      *Utf8Str,
+  OUT CHAR16     **Ucs2StrAddr
+  )
+{
+  EFI_STATUS    Status;
+  UINTN         Utf8StrIndex;
+  UINTN         Utf8StrLength;
+  UINTN         Ucs2StrIndex;
+  UINT8         Utf8BufferSize;
+  CHAR16        *Ucs2StrTemp;
+
+  if (Utf8Str == NULL || Ucs2StrAddr == NULL) {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  //
+  // It is not an Ascii string, calculate string length.
+  //
+  Utf8StrLength = 0;
+  while (*(Utf8Str + Utf8StrLength) != '\0') {
+    Utf8StrLength ++;
+  }
+
+  //
+  // UCS2 string shall not be longer than the UTF8 string.
+  //
+  Ucs2StrTemp = AllocateZeroPool ((Utf8StrLength + 1) * sizeof (CHAR16));
+  if (Ucs2StrTemp == NULL) {
+    return EFI_OUT_OF_RESOURCES;
+  }
+
+  Utf8StrIndex = 0;
+  Ucs2StrIndex = 0;
+  while (Utf8Str[Utf8StrIndex] != '\0') {
+
+    if (CompareMem (Utf8Str + Utf8StrIndex, "\\u", 2) == 0 &&
+      Utf8StrLength - Utf8StrIndex >= JSON_UNICODE_FORMAT_LEN) {
+
+      Status = GetUCS2CharByFormat (Utf8Str + Utf8StrIndex, Ucs2StrTemp + Ucs2StrIndex);
+      if (!EFI_ERROR (Status)) {
+
+        Utf8StrIndex += JSON_UNICODE_FORMAT_LEN;
+        Ucs2StrIndex ++;
+      } else {
+
+        StrCpyS (Ucs2StrTemp + Ucs2StrIndex, 3, L"\\u");
+
+        Ucs2StrIndex += 2;
+        Utf8StrIndex += 2;
+      }
+    } else {
+
+      Utf8BufferSize = GetUTF8SizeForUCS2 (Utf8Str + Utf8StrIndex);
+      if (Utf8BufferSize == 0 || Utf8StrLength - Utf8StrIndex < Utf8BufferSize) {
+
+        FreePool (Ucs2StrTemp);
+        return EFI_INVALID_PARAMETER;
+      }
+
+      Status = UTF8ToUCS2Char (Utf8Str + Utf8StrIndex, Ucs2StrTemp + Ucs2StrIndex);
+      if (EFI_ERROR (Status)) {
+
+        FreePool (Ucs2StrTemp);
+        return EFI_INVALID_PARAMETER;
+      }
+
+      Ucs2StrIndex ++;
+      Utf8StrIndex += Utf8BufferSize;
+    }
+  }
+
+  *Ucs2StrAddr = AllocateZeroPool ((Ucs2StrIndex + 1) * sizeof (CHAR16));
+  if (*Ucs2StrAddr == NULL) {
+
+    FreePool (Ucs2StrTemp);
+    return EFI_OUT_OF_RESOURCES;
+  }
+
+  StrCpyS (*Ucs2StrAddr, Ucs2StrIndex + 1, Ucs2StrTemp);
+  *(*Ucs2StrAddr + Ucs2StrIndex) = L'\0';
+  FreePool (Ucs2StrTemp);
+
+  return EFI_SUCCESS;
+}
+
diff --git a/RedfishPkg/Library/JsonLib/JsonUtilities.h b/RedfishPkg/Library/JsonLib/JsonUtilities.h
new file mode 100644
index 0000000000..1aaa4d31e2
--- /dev/null
+++ b/RedfishPkg/Library/JsonLib/JsonUtilities.h
@@ -0,0 +1,69 @@
+/** @file
+  Utility functions for JSON operations.
+
+  Copyright (c) 2019, Intel Corporation. All rights reserved.<BR>
+ (C) Copyright 2020 Hewlett Packard Enterprise Development LP<BR>
+
+    SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#ifndef JSON_UTILITIES_H_
+#define JSON_UTILITIES_H_
+
+#include <Base.h>
+#include <Uefi.h>
+#include <Library/BaseLib.h>
+#include <Library/BaseMemoryLib.h>
+#include <Library/DebugLib.h>
+#include <Library/PrintLib.h>
+#include <Library/MemoryAllocationLib.h>
+#include "jansson.h"
+
+#define JSON_UNICODE_FORMAT_LEN    6       ///  L"\u0000"
+#define JSON_UNICODE_FORMAT_SIZE   7
+
+#define JSON_UNICODE_FORMAT_CHAR_LEN    2
+#define JSON_UNICODE_FORMAT_CHAR_SIZE   3
+
+#define UTF8_BUFFER_FOR_UCS2_MAX_SIZE   3
+
+/**
+  Convert a UCS2 string to a UTF8 encoded string.
+
+  @param[in]    Ucs2Str                The provided UCS2 string.
+  @param[out]   Utf8StrAddr            The converted UTF8 string address. Caller
+                                       is responsible for Free this string.
+
+  @retval       EFI_INVALID_PARAMETER  One or more parameters are invalid.
+  @retval       EFI_OUT_OF_RESOURCES   System runs out of resources.
+  @retval       EFI_SUCCESS            The UTF8 encoded string has been converted.
+
+**/
+EFI_STATUS
+UCS2StrToUTF8 (
+  IN  CHAR16     *Ucs2Str,
+  OUT CHAR8      **Utf8StrAddr
+  );
+
+/**
+  Convert a UTF8 encoded string to a UCS2 string.
+
+  @param[in]    Utf8Str                The provided UTF8 encoded string.
+  @param[out]   Ucs2StrAddr            The converted UCS2 string address. Caller
+                                       is responsible for Free this string.
+
+  @retval       EFI_INVALID_PARAMETER  The UTF8 encoded string is not valid to
+                                       convert to UCS2 string.
+                                       One or more parameters are invalid.
+  @retval       EFI_OUT_OF_RESOURCES   System runs out of resources.
+  @retval       EFI_SUCCESS            The UCS2 string has been converted.
+
+**/
+EFI_STATUS
+UTF8StrToUCS2 (
+  IN  CHAR8      *Utf8Str,
+  OUT CHAR16     **Ucs2StrAddr
+  );
+
+#endif
diff --git a/RedfishPkg/Library/JsonLib/Readme.txt b/RedfishPkg/Library/JsonLib/Readme.txt
new file mode 100644
index 0000000000..cc149196b9
--- /dev/null
+++ b/RedfishPkg/Library/JsonLib/Readme.txt
@@ -0,0 +1,40 @@
+=============================================================================
+                             Introduction
+=============================================================================
+  Jansson is a C library for encoding, decoding and manipulating JSON data.
+Its main features and design principles are:
+
+  - Simple and intuitive API and data model
+  - Comprehensive documentation
+  - No dependencies on other libraries
+  - Full Unicode support (UTF-8)
+  - Extensive test suite
+
+  Jansson is licensed under the MIT license(refer to ReadMe.rst under edk2).
+It is used in production and its API is stable. It works on numerous
+platforms, including numerous Unix like systems and Windows. It's suitable
+for use on any system, including desktop, server, and small embedded systems.
+
+  In UEFI/EDKII environment, Redfish project consumes jansson to achieve JSON
+operations.
+
+* Jansson version on edk2: 2.13.1
+
+* EDKII jansson library wrapper:
+   - JsonLib.h:
+     This is the denifitions of EDKII JSON APIs which are mapped to
+     jannson funcitons accordingly.
+
+   - JanssonJsonLibMapping.h:
+     This is the wrapper to map funcitons and definitions used in
+     native jannson applications to edk2 JsonLib. This avoids the
+     modifications on native jannson applications to be built under
+     edk2 environment.
+
+*Known issue:
+   Build fail with jansson/src/load.c, add code in load.c to conditionally
+   use stdin according to HAVE_UNISTD_H macro. The PR is submitted to
+   jansson open source community.
+   https://github.com/akheron/jansson/pull/558
+
+
diff --git a/RedfishPkg/Library/JsonLib/assert.h b/RedfishPkg/Library/JsonLib/assert.h
new file mode 100644
index 0000000000..8f9eb748e4
--- /dev/null
+++ b/RedfishPkg/Library/JsonLib/assert.h
@@ -0,0 +1,16 @@
+/** @file
+  Include file to support building the third-party jansson library.
+
+ Copyright (c) 2019, Intel Corporation. All rights reserved.<BR>
+ (C) Copyright 2020 Hewlett Packard Enterprise Development LP<BR>
+
+    SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#ifndef JANSSON_CRT_ASSERT_H_
+#define JANSSON_CRT_ASSERT_H_
+
+#include <JanssonCrtLibSupport.h>
+
+#endif
diff --git a/RedfishPkg/Library/JsonLib/errno.h b/RedfishPkg/Library/JsonLib/errno.h
new file mode 100644
index 0000000000..b1191b225a
--- /dev/null
+++ b/RedfishPkg/Library/JsonLib/errno.h
@@ -0,0 +1,16 @@
+/** @file
+  Include file to support building the third-party jansson library.
+
+ Copyright (c) 2019, Intel Corporation. All rights reserved.<BR>
+ (C) Copyright 2020 Hewlett Packard Enterprise Development LP<BR>
+
+    SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#ifndef JANSSON_CRT_ERRNO_H_
+#define JANSSON_CRT_ERRNO_H_
+
+#include <JanssonCrtLibSupport.h>
+
+#endif
diff --git a/RedfishPkg/Library/JsonLib/jansson_config.h b/RedfishPkg/Library/JsonLib/jansson_config.h
new file mode 100644
index 0000000000..6b154289df
--- /dev/null
+++ b/RedfishPkg/Library/JsonLib/jansson_config.h
@@ -0,0 +1,60 @@
+/** @file
+ * Copyright (c) 2010-2016 Petri Lehtinen <petri at digip.org>
+ *
+ * Jansson is free software; you can redistribute it and/or modify
+ * it under the terms of the MIT license. See LICENSE for details.
+ *
+ *
+ * This file specifies a part of the site-specific configuration for
+ * Jansson, namely those things that affect the public API in
+ * jansson.h.
+ *
+ * The configure script copies this file to jansson_config.h and
+ * replaces @var@ substitutions by values that fit your system. If you
+ * cannot run the configure script, you can do the value substitution
+ * by hand.
+
+ jansson open source license,
+ https://github.com/akheron/jansson/blob/master/LICENSE
+
+ (C) Copyright 2020 Hewlett Packard Enterprise Development LP<BR>
+
+    SPDX-License-Identifier: BSD-2-Clause-Patent
+ **/
+
+#ifndef JANSSON_CONFIG_H_
+#define JANSSON_CONFIG_H_
+
+/* If your compiler supports the inline keyword in C, JSON_INLINE is
+   defined to `inline', otherwise empty. In C++, the inline is always
+   supported. */
+#ifdef __cplusplus
+#define JSON_INLINE inline
+#else
+#define JSON_INLINE
+#endif
+
+/* If your compiler supports the `long long` type and the strtoll()
+   library function, JSON_INTEGER_IS_LONG_LONG is defined to 1,
+   otherwise to 0. */
+#define JSON_INTEGER_IS_LONG_LONG 1
+
+/* If locale.h and localeconv() are available, define to 1,
+   otherwise to 0. */
+#define JSON_HAVE_LOCALECONV 0
+
+/* If __atomic builtins are available they will be used to manage
+   reference counts of json_t. */
+#define JSON_HAVE_ATOMIC_BUILTINS 0
+
+/* If __atomic builtins are not available we try using __sync builtins
+   to manage reference counts of json_t. */
+#define JSON_HAVE_SYNC_BUILTINS 0
+
+/* Maximum recursion depth for parsing JSON input.
+   This limits the depth of e.g. array-within-array constructions. */
+#define JSON_PARSER_MAX_DEPTH 2048
+
+#define SUPPORT_JANSSON_JSON_REAL 1
+
+#endif
diff --git a/RedfishPkg/Library/JsonLib/jansson_private_config.h b/RedfishPkg/Library/JsonLib/jansson_private_config.h
new file mode 100644
index 0000000000..268f91ef8a
--- /dev/null
+++ b/RedfishPkg/Library/JsonLib/jansson_private_config.h
@@ -0,0 +1,19 @@
+/** @file
+  Jansson private configurations for UEFI support.
+
+ Copyright (c) 2019, Intel Corporation. All rights reserved.<BR>
+ (C) Copyright 2020 Hewlett Packard Enterprise Development LP<BR>
+
+    SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#ifndef JANSSON_PRIVATE_CONFIG_H_
+#define JANSSON_PRIVATE_CONFIG_H_
+
+#define HAVE_SYS_TIME_H 1
+#define HAVE_SYS_TYPES_H 1
+
+#define INITIAL_HASHTABLE_ORDER 3
+
+#endif
diff --git a/RedfishPkg/Library/JsonLib/limits.h b/RedfishPkg/Library/JsonLib/limits.h
new file mode 100644
index 0000000000..1a544adece
--- /dev/null
+++ b/RedfishPkg/Library/JsonLib/limits.h
@@ -0,0 +1,16 @@
+/** @file
+  Include file to support building the third-party jansson library.
+
+ Copyright (c) 2019, Intel Corporation. All rights reserved.<BR>
+ (C) Copyright 2020 Hewlett Packard Enterprise Development LP<BR>
+
+    SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#ifndef JANSSON_CRT_LIMITS_H_
+#define JANSSON_CRT_LIMITS_H_
+
+#include <JanssonCrtLibSupport.h>
+
+#endif
diff --git a/RedfishPkg/Library/JsonLib/load.c b/RedfishPkg/Library/JsonLib/load.c
new file mode 100644
index 0000000000..92063e63cb
--- /dev/null
+++ b/RedfishPkg/Library/JsonLib/load.c
@@ -0,0 +1,1111 @@
+/*
+ * Copyright (c) 2009-2016 Petri Lehtinen <petri at digip.org>
+ *
+ * Jansson is free software; you can redistribute it and/or modify
+ * it under the terms of the MIT license. See LICENSE for details.
+
+ (C) Copyright 2020 Hewlett Packard Enterprise Development LP<BR>
+
+    SPDX-License-Identifier: BSD-2-Clause-Patent
+ */
+
+#ifndef _GNU_SOURCE
+#define _GNU_SOURCE
+#endif
+
+#include "jansson_private.h"
+
+#include <assert.h>
+#include <errno.h>
+#include <limits.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#ifdef HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+
+#include "jansson.h"
+#include "strbuffer.h"
+#include "utf.h"
+
+#define STREAM_STATE_OK    0
+#define STREAM_STATE_EOF   -1
+#define STREAM_STATE_ERROR -2
+
+#define TOKEN_INVALID -1
+#define TOKEN_EOF     0
+#define TOKEN_STRING  256
+#define TOKEN_INTEGER 257
+#define TOKEN_REAL    258
+#define TOKEN_TRUE    259
+#define TOKEN_FALSE   260
+#define TOKEN_NULL    261
+
+/* Locale independent versions of isxxx() functions */
+#define l_isupper(c) ('A' <= (c) && (c) <= 'Z')
+#define l_islower(c) ('a' <= (c) && (c) <= 'z')
+#define l_isalpha(c) (l_isupper(c) || l_islower(c))
+#define l_isdigit(c) ('0' <= (c) && (c) <= '9')
+#define l_isxdigit(c)                                                                    \
+    (l_isdigit(c) || ('A' <= (c) && (c) <= 'F') || ('a' <= (c) && (c) <= 'f'))
+
+/* Read one byte from stream, convert to unsigned char, then int, and
+   return. return EOF on end of file. This corresponds to the
+   behaviour of fgetc(). */
+typedef int (*get_func)(void *data);
+
+typedef struct {
+    get_func get;
+    void *data;
+    char buffer[5];
+    size_t buffer_pos;
+    int state;
+    int line;
+    int column, last_column;
+    size_t position;
+} stream_t;
+
+typedef struct {
+    stream_t stream;
+    strbuffer_t saved_text;
+    size_t flags;
+    size_t depth;
+    int token;
+    union {
+        struct {
+            char *val;
+            size_t len;
+        } string;
+        json_int_t integer;
+        double real;
+    } value;
+} lex_t;
+
+#define stream_to_lex(stream) container_of(stream, lex_t, stream)
+
+/*** error reporting ***/
+
+static void error_set(json_error_t *error, const lex_t *lex, enum json_error_code code,
+                      const char *msg, ...) {
+    va_list ap;
+    char msg_text[JSON_ERROR_TEXT_LENGTH];
+    char msg_with_context[JSON_ERROR_TEXT_LENGTH];
+
+    int line = -1, col = -1;
+    size_t pos = 0;
+    const char *result = msg_text;
+
+    if (!error)
+        return;
+
+    va_start(ap, msg);
+    vsnprintf(msg_text, JSON_ERROR_TEXT_LENGTH, msg, ap);
+    msg_text[JSON_ERROR_TEXT_LENGTH - 1] = '\0';
+    va_end(ap);
+
+    if (lex) {
+        const char *saved_text = strbuffer_value(&lex->saved_text);
+
+        line = lex->stream.line;
+        col = lex->stream.column;
+        pos = lex->stream.position;
+
+        if (saved_text && saved_text[0]) {
+            if (lex->saved_text.length <= 20) {
+                snprintf(msg_with_context, JSON_ERROR_TEXT_LENGTH, "%s near '%s'",
+                         msg_text, saved_text);
+                msg_with_context[JSON_ERROR_TEXT_LENGTH - 1] = '\0';
+                result = msg_with_context;
+            }
+        } else {
+            if (code == json_error_invalid_syntax) {
+                /* More specific error code for premature end of file. */
+                code = json_error_premature_end_of_input;
+            }
+            if (lex->stream.state == STREAM_STATE_ERROR) {
+                /* No context for UTF-8 decoding errors */
+                result = msg_text;
+            } else {
+                snprintf(msg_with_context, JSON_ERROR_TEXT_LENGTH, "%s near end of file",
+                         msg_text);
+                msg_with_context[JSON_ERROR_TEXT_LENGTH - 1] = '\0';
+                result = msg_with_context;
+            }
+        }
+    }
+
+    jsonp_error_set(error, line, col, pos, code, "%s", result);
+}
+
+/*** lexical analyzer ***/
+
+static void stream_init(stream_t *stream, get_func get, void *data) {
+    stream->get = get;
+    stream->data = data;
+    stream->buffer[0] = '\0';
+    stream->buffer_pos = 0;
+
+    stream->state = STREAM_STATE_OK;
+    stream->line = 1;
+    stream->column = 0;
+    stream->position = 0;
+}
+
+static int stream_get(stream_t *stream, json_error_t *error) {
+    int c;
+
+    if (stream->state != STREAM_STATE_OK)
+        return stream->state;
+
+    if (!stream->buffer[stream->buffer_pos]) {
+        c = stream->get(stream->data);
+        if (c == EOF) {
+            stream->state = STREAM_STATE_EOF;
+            return STREAM_STATE_EOF;
+        }
+
+        stream->buffer[0] = c;
+        stream->buffer_pos = 0;
+
+        if (0x80 <= c && c <= 0xFF) {
+            /* multi-byte UTF-8 sequence */
+            size_t i, count;
+
+            count = utf8_check_first(c);
+            if (!count)
+                goto out;
+
+            assert(count >= 2);
+
+            for (i = 1; i < count; i++)
+                stream->buffer[i] = stream->get(stream->data);
+
+            if (!utf8_check_full(stream->buffer, count, NULL))
+                goto out;
+
+            stream->buffer[count] = '\0';
+        } else
+            stream->buffer[1] = '\0';
+    }
+
+    c = stream->buffer[stream->buffer_pos++];
+
+    stream->position++;
+    if (c == '\n') {
+        stream->line++;
+        stream->last_column = stream->column;
+        stream->column = 0;
+    } else if (utf8_check_first(c)) {
+        /* track the Unicode character column, so increment only if
+           this is the first character of a UTF-8 sequence */
+        stream->column++;
+    }
+
+    return c;
+
+out:
+    stream->state = STREAM_STATE_ERROR;
+    error_set(error, stream_to_lex(stream), json_error_invalid_utf8,
+              "unable to decode byte 0x%x", c);
+    return STREAM_STATE_ERROR;
+}
+
+static void stream_unget(stream_t *stream, int c) {
+    if (c == STREAM_STATE_EOF || c == STREAM_STATE_ERROR)
+        return;
+
+    stream->position--;
+    if (c == '\n') {
+        stream->line--;
+        stream->column = stream->last_column;
+    } else if (utf8_check_first(c))
+        stream->column--;
+
+    assert(stream->buffer_pos > 0);
+    stream->buffer_pos--;
+    assert(stream->buffer[stream->buffer_pos] == c);
+}
+
+static int lex_get(lex_t *lex, json_error_t *error) {
+    return stream_get(&lex->stream, error);
+}
+
+static void lex_save(lex_t *lex, int c) { strbuffer_append_byte(&lex->saved_text, c); }
+
+static int lex_get_save(lex_t *lex, json_error_t *error) {
+    int c = stream_get(&lex->stream, error);
+    if (c != STREAM_STATE_EOF && c != STREAM_STATE_ERROR)
+        lex_save(lex, c);
+    return c;
+}
+
+static void lex_unget(lex_t *lex, int c) { stream_unget(&lex->stream, c); }
+
+static void lex_unget_unsave(lex_t *lex, int c) {
+    if (c != STREAM_STATE_EOF && c != STREAM_STATE_ERROR) {
+/* Since we treat warnings as errors, when assertions are turned
+ * off the "d" variable would be set but never used. Which is
+ * treated as an error by GCC.
+ */
+#ifndef NDEBUG
+        char d;
+#endif
+        stream_unget(&lex->stream, c);
+#ifndef NDEBUG
+        d =
+#endif
+            strbuffer_pop(&lex->saved_text);
+        assert(c == d);
+    }
+}
+
+static void lex_save_cached(lex_t *lex) {
+    while (lex->stream.buffer[lex->stream.buffer_pos] != '\0') {
+        lex_save(lex, lex->stream.buffer[lex->stream.buffer_pos]);
+        lex->stream.buffer_pos++;
+        lex->stream.position++;
+    }
+}
+
+static void lex_free_string(lex_t *lex) {
+    jsonp_free(lex->value.string.val);
+    lex->value.string.val = NULL;
+    lex->value.string.len = 0;
+}
+
+/* assumes that str points to 'u' plus at least 4 valid hex digits */
+static int32_t decode_unicode_escape(const char *str) {
+    int i;
+    int32_t value = 0;
+
+    assert(str[0] == 'u');
+
+    for (i = 1; i <= 4; i++) {
+        char c = str[i];
+        value <<= 4;
+        if (l_isdigit(c))
+            value += c - '0';
+        else if (l_islower(c))
+            value += c - 'a' + 10;
+        else if (l_isupper(c))
+            value += c - 'A' + 10;
+        else
+            return -1;
+    }
+
+    return value;
+}
+
+static void lex_scan_string(lex_t *lex, json_error_t *error) {
+    int c;
+    const char *p;
+    char *t;
+    int i;
+
+    lex->value.string.val = NULL;
+    lex->token = TOKEN_INVALID;
+
+    c = lex_get_save(lex, error);
+
+    while (c != '"') {
+        if (c == STREAM_STATE_ERROR)
+            goto out;
+
+        else if (c == STREAM_STATE_EOF) {
+            error_set(error, lex, json_error_premature_end_of_input,
+                      "premature end of input");
+            goto out;
+        }
+
+        else if (0 <= c && c <= 0x1F) {
+            /* control character */
+            lex_unget_unsave(lex, c);
+            if (c == '\n')
+                error_set(error, lex, json_error_invalid_syntax, "unexpected newline");
+            else
+                error_set(error, lex, json_error_invalid_syntax, "control character 0x%x",
+                          c);
+            goto out;
+        }
+
+        else if (c == '\\') {
+            c = lex_get_save(lex, error);
+            if (c == 'u') {
+                c = lex_get_save(lex, error);
+                for (i = 0; i < 4; i++) {
+                    if (!l_isxdigit(c)) {
+                        error_set(error, lex, json_error_invalid_syntax,
+                                  "invalid escape");
+                        goto out;
+                    }
+                    c = lex_get_save(lex, error);
+                }
+            } else if (c == '"' || c == '\\' || c == '/' || c == 'b' || c == 'f' ||
+                       c == 'n' || c == 'r' || c == 't')
+                c = lex_get_save(lex, error);
+            else {
+                error_set(error, lex, json_error_invalid_syntax, "invalid escape");
+                goto out;
+            }
+        } else
+            c = lex_get_save(lex, error);
+    }
+
+    /* the actual value is at most of the same length as the source
+       string, because:
+         - shortcut escapes (e.g. "\t") (length 2) are converted to 1 byte
+         - a single \uXXXX escape (length 6) is converted to at most 3 bytes
+         - two \uXXXX escapes (length 12) forming an UTF-16 surrogate pair
+           are converted to 4 bytes
+    */
+    t = jsonp_malloc(lex->saved_text.length + 1);
+    if (!t) {
+        /* this is not very nice, since TOKEN_INVALID is returned */
+        goto out;
+    }
+    lex->value.string.val = t;
+
+    /* + 1 to skip the " */
+    p = strbuffer_value(&lex->saved_text) + 1;
+
+    while (*p != '"') {
+        if (*p == '\\') {
+            p++;
+            if (*p == 'u') {
+                size_t length;
+                int32_t value;
+
+                value = decode_unicode_escape(p);
+                if (value < 0) {
+                    error_set(error, lex, json_error_invalid_syntax,
+                              "invalid Unicode escape '%.6s'", p - 1);
+                    goto out;
+                }
+                p += 5;
+
+                if (0xD800 <= value && value <= 0xDBFF) {
+                    /* surrogate pair */
+                    if (*p == '\\' && *(p + 1) == 'u') {
+                        int32_t value2 = decode_unicode_escape(++p);
+                        if (value2 < 0) {
+                            error_set(error, lex, json_error_invalid_syntax,
+                                      "invalid Unicode escape '%.6s'", p - 1);
+                            goto out;
+                        }
+                        p += 5;
+
+                        if (0xDC00 <= value2 && value2 <= 0xDFFF) {
+                            /* valid second surrogate */
+                            value =
+                                ((value - 0xD800) << 10) + (value2 - 0xDC00) + 0x10000;
+                        } else {
+                            /* invalid second surrogate */
+                            error_set(error, lex, json_error_invalid_syntax,
+                                      "invalid Unicode '\\u%04X\\u%04X'", value, value2);
+                            goto out;
+                        }
+                    } else {
+                        /* no second surrogate */
+                        error_set(error, lex, json_error_invalid_syntax,
+                                  "invalid Unicode '\\u%04X'", value);
+                        goto out;
+                    }
+                } else if (0xDC00 <= value && value <= 0xDFFF) {
+                    error_set(error, lex, json_error_invalid_syntax,
+                              "invalid Unicode '\\u%04X'", value);
+                    goto out;
+                }
+
+                if (utf8_encode(value, t, &length))
+                    assert(0);
+                t += length;
+            } else {
+                switch (*p) {
+                    case '"':
+                    case '\\':
+                    case '/':
+                        *t = *p;
+                        break;
+                    case 'b':
+                        *t = '\b';
+                        break;
+                    case 'f':
+                        *t = '\f';
+                        break;
+                    case 'n':
+                        *t = '\n';
+                        break;
+                    case 'r':
+                        *t = '\r';
+                        break;
+                    case 't':
+                        *t = '\t';
+                        break;
+                    default:
+                        assert(0);
+                }
+                t++;
+                p++;
+            }
+        } else
+            *(t++) = *(p++);
+    }
+    *t = '\0';
+    lex->value.string.len = t - lex->value.string.val;
+    lex->token = TOKEN_STRING;
+    return;
+
+out:
+    lex_free_string(lex);
+}
+
+#ifndef JANSSON_USING_CMAKE /* disabled if using cmake */
+#if JSON_INTEGER_IS_LONG_LONG
+#ifdef _MSC_VER /* Microsoft Visual Studio */
+#define json_strtoint _strtoi64
+#else
+#define json_strtoint strtoll
+#endif
+#else
+#define json_strtoint strtol
+#endif
+#endif
+
+static int lex_scan_number(lex_t *lex, int c, json_error_t *error) {
+    const char *saved_text;
+    char *end;
+    double doubleval;
+
+    lex->token = TOKEN_INVALID;
+
+    if (c == '-')
+        c = lex_get_save(lex, error);
+
+    if (c == '0') {
+        c = lex_get_save(lex, error);
+        if (l_isdigit(c)) {
+            lex_unget_unsave(lex, c);
+            goto out;
+        }
+    } else if (l_isdigit(c)) {
+        do
+            c = lex_get_save(lex, error);
+        while (l_isdigit(c));
+    } else {
+        lex_unget_unsave(lex, c);
+        goto out;
+    }
+
+    if (!(lex->flags & JSON_DECODE_INT_AS_REAL) && c != '.' && c != 'E' && c != 'e') {
+        json_int_t intval;
+
+        lex_unget_unsave(lex, c);
+
+        saved_text = strbuffer_value(&lex->saved_text);
+
+        errno = 0;
+        intval = json_strtoint(saved_text, &end, 10);
+        if (errno == ERANGE) {
+            if (intval < 0)
+                error_set(error, lex, json_error_numeric_overflow,
+                          "too big negative integer");
+            else
+                error_set(error, lex, json_error_numeric_overflow, "too big integer");
+            goto out;
+        }
+
+        assert(end == saved_text + lex->saved_text.length);
+
+        lex->token = TOKEN_INTEGER;
+        lex->value.integer = intval;
+        return 0;
+    }
+
+    if (c == '.') {
+        c = lex_get(lex, error);
+        if (!l_isdigit(c)) {
+            lex_unget(lex, c);
+            goto out;
+        }
+        lex_save(lex, c);
+
+        do
+            c = lex_get_save(lex, error);
+        while (l_isdigit(c));
+    }
+
+    if (c == 'E' || c == 'e') {
+        c = lex_get_save(lex, error);
+        if (c == '+' || c == '-')
+            c = lex_get_save(lex, error);
+
+        if (!l_isdigit(c)) {
+            lex_unget_unsave(lex, c);
+            goto out;
+        }
+
+        do
+            c = lex_get_save(lex, error);
+        while (l_isdigit(c));
+    }
+
+    lex_unget_unsave(lex, c);
+
+    if (jsonp_strtod(&lex->saved_text, &doubleval)) {
+        error_set(error, lex, json_error_numeric_overflow, "real number overflow");
+        goto out;
+    }
+
+    lex->token = TOKEN_REAL;
+    lex->value.real = doubleval;
+    return 0;
+
+out:
+    return -1;
+}
+
+static int lex_scan(lex_t *lex, json_error_t *error) {
+    int c;
+
+    strbuffer_clear(&lex->saved_text);
+
+    if (lex->token == TOKEN_STRING)
+        lex_free_string(lex);
+
+    do
+        c = lex_get(lex, error);
+    while (c == ' ' || c == '\t' || c == '\n' || c == '\r');
+
+    if (c == STREAM_STATE_EOF) {
+        lex->token = TOKEN_EOF;
+        goto out;
+    }
+
+    if (c == STREAM_STATE_ERROR) {
+        lex->token = TOKEN_INVALID;
+        goto out;
+    }
+
+    lex_save(lex, c);
+
+    if (c == '{' || c == '}' || c == '[' || c == ']' || c == ':' || c == ',')
+        lex->token = c;
+
+    else if (c == '"')
+        lex_scan_string(lex, error);
+
+    else if (l_isdigit(c) || c == '-') {
+        if (lex_scan_number(lex, c, error))
+            goto out;
+    }
+
+    else if (l_isalpha(c)) {
+        /* eat up the whole identifier for clearer error messages */
+        const char *saved_text;
+
+        do
+            c = lex_get_save(lex, error);
+        while (l_isalpha(c));
+        lex_unget_unsave(lex, c);
+
+        saved_text = strbuffer_value(&lex->saved_text);
+
+        if (strcmp(saved_text, "true") == 0)
+            lex->token = TOKEN_TRUE;
+        else if (strcmp(saved_text, "false") == 0)
+            lex->token = TOKEN_FALSE;
+        else if (strcmp(saved_text, "null") == 0)
+            lex->token = TOKEN_NULL;
+        else
+            lex->token = TOKEN_INVALID;
+    }
+
+    else {
+        /* save the rest of the input UTF-8 sequence to get an error
+           message of valid UTF-8 */
+        lex_save_cached(lex);
+        lex->token = TOKEN_INVALID;
+    }
+
+out:
+    return lex->token;
+}
+
+static char *lex_steal_string(lex_t *lex, size_t *out_len) {
+    char *result = NULL;
+    if (lex->token == TOKEN_STRING) {
+        result = lex->value.string.val;
+        *out_len = lex->value.string.len;
+        lex->value.string.val = NULL;
+        lex->value.string.len = 0;
+    }
+    return result;
+}
+
+static int lex_init(lex_t *lex, get_func get, size_t flags, void *data) {
+    stream_init(&lex->stream, get, data);
+    if (strbuffer_init(&lex->saved_text))
+        return -1;
+
+    lex->flags = flags;
+    lex->token = TOKEN_INVALID;
+    return 0;
+}
+
+static void lex_close(lex_t *lex) {
+    if (lex->token == TOKEN_STRING)
+        lex_free_string(lex);
+    strbuffer_close(&lex->saved_text);
+}
+
+/*** parser ***/
+
+static json_t *parse_value(lex_t *lex, size_t flags, json_error_t *error);
+
+static json_t *parse_object(lex_t *lex, size_t flags, json_error_t *error) {
+    json_t *object = json_object();
+    if (!object)
+        return NULL;
+
+    lex_scan(lex, error);
+    if (lex->token == '}')
+        return object;
+
+    while (1) {
+        char *key;
+        size_t len;
+        json_t *value;
+
+        if (lex->token != TOKEN_STRING) {
+            error_set(error, lex, json_error_invalid_syntax, "string or '}' expected");
+            goto error;
+        }
+
+        key = lex_steal_string(lex, &len);
+        if (!key)
+            return NULL;
+        if (memchr(key, '\0', len)) {
+            jsonp_free(key);
+            error_set(error, lex, json_error_null_byte_in_key,
+                      "NUL byte in object key not supported");
+            goto error;
+        }
+
+        if (flags & JSON_REJECT_DUPLICATES) {
+            if (json_object_get(object, key)) {
+                jsonp_free(key);
+                error_set(error, lex, json_error_duplicate_key, "duplicate object key");
+                goto error;
+            }
+        }
+
+        lex_scan(lex, error);
+        if (lex->token != ':') {
+            jsonp_free(key);
+            error_set(error, lex, json_error_invalid_syntax, "':' expected");
+            goto error;
+        }
+
+        lex_scan(lex, error);
+        value = parse_value(lex, flags, error);
+        if (!value) {
+            jsonp_free(key);
+            goto error;
+        }
+
+        if (json_object_set_new_nocheck(object, key, value)) {
+            jsonp_free(key);
+            goto error;
+        }
+
+        jsonp_free(key);
+
+        lex_scan(lex, error);
+        if (lex->token != ',')
+            break;
+
+        lex_scan(lex, error);
+    }
+
+    if (lex->token != '}') {
+        error_set(error, lex, json_error_invalid_syntax, "'}' expected");
+        goto error;
+    }
+
+    return object;
+
+error:
+    json_decref(object);
+    return NULL;
+}
+
+static json_t *parse_array(lex_t *lex, size_t flags, json_error_t *error) {
+    json_t *array = json_array();
+    if (!array)
+        return NULL;
+
+    lex_scan(lex, error);
+    if (lex->token == ']')
+        return array;
+
+    while (lex->token) {
+        json_t *elem = parse_value(lex, flags, error);
+        if (!elem)
+            goto error;
+
+        if (json_array_append_new(array, elem)) {
+            goto error;
+        }
+
+        lex_scan(lex, error);
+        if (lex->token != ',')
+            break;
+
+        lex_scan(lex, error);
+    }
+
+    if (lex->token != ']') {
+        error_set(error, lex, json_error_invalid_syntax, "']' expected");
+        goto error;
+    }
+
+    return array;
+
+error:
+    json_decref(array);
+    return NULL;
+}
+
+static json_t *parse_value(lex_t *lex, size_t flags, json_error_t *error) {
+    json_t *json;
+
+    lex->depth++;
+    if (lex->depth > JSON_PARSER_MAX_DEPTH) {
+        error_set(error, lex, json_error_stack_overflow, "maximum parsing depth reached");
+        return NULL;
+    }
+
+    switch (lex->token) {
+        case TOKEN_STRING: {
+            const char *value = lex->value.string.val;
+            size_t len = lex->value.string.len;
+
+            if (!(flags & JSON_ALLOW_NUL)) {
+                if (memchr(value, '\0', len)) {
+                    error_set(error, lex, json_error_null_character,
+                              "\\u0000 is not allowed without JSON_ALLOW_NUL");
+                    return NULL;
+                }
+            }
+
+            json = jsonp_stringn_nocheck_own(value, len);
+            lex->value.string.val = NULL;
+            lex->value.string.len = 0;
+            break;
+        }
+
+        case TOKEN_INTEGER: {
+            json = json_integer(lex->value.integer);
+            break;
+        }
+
+        case TOKEN_REAL: {
+            json = json_real(lex->value.real);
+            break;
+        }
+
+        case TOKEN_TRUE:
+            json = json_true();
+            break;
+
+        case TOKEN_FALSE:
+            json = json_false();
+            break;
+
+        case TOKEN_NULL:
+            json = json_null();
+            break;
+
+        case '{':
+            json = parse_object(lex, flags, error);
+            break;
+
+        case '[':
+            json = parse_array(lex, flags, error);
+            break;
+
+        case TOKEN_INVALID:
+            error_set(error, lex, json_error_invalid_syntax, "invalid token");
+            return NULL;
+
+        default:
+            error_set(error, lex, json_error_invalid_syntax, "unexpected token");
+            return NULL;
+    }
+
+    if (!json)
+        return NULL;
+
+    lex->depth--;
+    return json;
+}
+
+static json_t *parse_json(lex_t *lex, size_t flags, json_error_t *error) {
+    json_t *result;
+
+    lex->depth = 0;
+
+    lex_scan(lex, error);
+    if (!(flags & JSON_DECODE_ANY)) {
+        if (lex->token != '[' && lex->token != '{') {
+            error_set(error, lex, json_error_invalid_syntax, "'[' or '{' expected");
+            return NULL;
+        }
+    }
+
+    result = parse_value(lex, flags, error);
+    if (!result)
+        return NULL;
+
+    if (!(flags & JSON_DISABLE_EOF_CHECK)) {
+        lex_scan(lex, error);
+        if (lex->token != TOKEN_EOF) {
+            error_set(error, lex, json_error_end_of_input_expected,
+                      "end of file expected");
+            json_decref(result);
+            return NULL;
+        }
+    }
+
+    if (error) {
+        /* Save the position even though there was no error */
+        error->position = (int)lex->stream.position;
+    }
+
+    return result;
+}
+
+typedef struct {
+    const char *data;
+    size_t pos;
+} string_data_t;
+
+static int string_get(void *data) {
+    char c;
+    string_data_t *stream = (string_data_t *)data;
+    c = stream->data[stream->pos];
+    if (c == '\0')
+        return EOF;
+    else {
+        stream->pos++;
+        return (unsigned char)c;
+    }
+}
+
+json_t *json_loads(const char *string, size_t flags, json_error_t *error) {
+    lex_t lex;
+    json_t *result;
+    string_data_t stream_data;
+
+    jsonp_error_init(error, "<string>");
+
+    if (string == NULL) {
+        error_set(error, NULL, json_error_invalid_argument, "wrong arguments");
+        return NULL;
+    }
+
+    stream_data.data = string;
+    stream_data.pos = 0;
+
+    if (lex_init(&lex, string_get, flags, (void *)&stream_data))
+        return NULL;
+
+    result = parse_json(&lex, flags, error);
+
+    lex_close(&lex);
+    return result;
+}
+
+typedef struct {
+    const char *data;
+    size_t len;
+    size_t pos;
+} buffer_data_t;
+
+static int buffer_get(void *data) {
+    char c;
+    buffer_data_t *stream = data;
+    if (stream->pos >= stream->len)
+        return EOF;
+
+    c = stream->data[stream->pos];
+    stream->pos++;
+    return (unsigned char)c;
+}
+
+json_t *json_loadb(const char *buffer, size_t buflen, size_t flags, json_error_t *error) {
+    lex_t lex;
+    json_t *result;
+    buffer_data_t stream_data;
+
+    jsonp_error_init(error, "<buffer>");
+
+    if (buffer == NULL) {
+        error_set(error, NULL, json_error_invalid_argument, "wrong arguments");
+        return NULL;
+    }
+
+    stream_data.data = buffer;
+    stream_data.pos = 0;
+    stream_data.len = buflen;
+
+    if (lex_init(&lex, buffer_get, flags, (void *)&stream_data))
+        return NULL;
+
+    result = parse_json(&lex, flags, error);
+
+    lex_close(&lex);
+    return result;
+}
+
+json_t *json_loadf(FILE *input, size_t flags, json_error_t *error) {
+    lex_t lex;
+    const char *source;
+    json_t *result;
+#ifdef HAVE_UNISTD_H
+    if (input == stdin)
+        source = "<stdin>";
+    else
+#endif
+        source = "<stream>";
+
+    jsonp_error_init(error, source);
+
+    if (input == NULL) {
+        error_set(error, NULL, json_error_invalid_argument, "wrong arguments");
+        return NULL;
+    }
+
+    if (lex_init(&lex, (get_func)fgetc, flags, input))
+        return NULL;
+
+    result = parse_json(&lex, flags, error);
+
+    lex_close(&lex);
+    return result;
+}
+
+static int fd_get_func(int *fd) {
+#ifdef HAVE_UNISTD_H
+    uint8_t c;
+    if (read(*fd, &c, 1) == 1)
+        return c;
+#endif
+    return EOF;
+}
+
+json_t *json_loadfd(int input, size_t flags, json_error_t *error) {
+    lex_t lex;
+    const char *source;
+    json_t *result;
+
+#ifdef HAVE_UNISTD_H
+    if (input == STDIN_FILENO)
+        source = "<stdin>";
+    else
+#endif
+        source = "<stream>";
+
+    jsonp_error_init(error, source);
+
+    if (input < 0) {
+        error_set(error, NULL, json_error_invalid_argument, "wrong arguments");
+        return NULL;
+    }
+
+    if (lex_init(&lex, (get_func)fd_get_func, flags, &input))
+        return NULL;
+
+    result = parse_json(&lex, flags, error);
+
+    lex_close(&lex);
+    return result;
+}
+
+json_t *json_load_file(const char *path, size_t flags, json_error_t *error) {
+    json_t *result;
+    FILE *fp;
+
+    jsonp_error_init(error, path);
+
+    if (path == NULL) {
+        error_set(error, NULL, json_error_invalid_argument, "wrong arguments");
+        return NULL;
+    }
+
+    fp = fopen(path, "rb");
+    if (!fp) {
+        error_set(error, NULL, json_error_cannot_open_file, "unable to open %s: %s", path,
+                  strerror(errno));
+        return NULL;
+    }
+
+    result = json_loadf(fp, flags, error);
+
+    fclose(fp);
+    return result;
+}
+
+#define MAX_BUF_LEN 1024
+
+typedef struct {
+    char data[MAX_BUF_LEN];
+    size_t len;
+    size_t pos;
+    json_load_callback_t callback;
+    void *arg;
+} callback_data_t;
+
+static int callback_get(void *data) {
+    char c;
+    callback_data_t *stream = data;
+
+    if (stream->pos >= stream->len) {
+        stream->pos = 0;
+        stream->len = stream->callback(stream->data, MAX_BUF_LEN, stream->arg);
+        if (stream->len == 0 || stream->len == (size_t)-1)
+            return EOF;
+    }
+
+    c = stream->data[stream->pos];
+    stream->pos++;
+    return (unsigned char)c;
+}
+
+json_t *json_load_callback(json_load_callback_t callback, void *arg, size_t flags,
+                           json_error_t *error) {
+    lex_t lex;
+    json_t *result;
+
+    callback_data_t stream_data;
+
+    memset(&stream_data, 0, sizeof(stream_data));
+    stream_data.callback = callback;
+    stream_data.arg = arg;
+
+    jsonp_error_init(error, "<callback>");
+
+    if (callback == NULL) {
+        error_set(error, NULL, json_error_invalid_argument, "wrong arguments");
+        return NULL;
+    }
+
+    if (lex_init(&lex, (get_func)callback_get, flags, &stream_data))
+        return NULL;
+
+    result = parse_json(&lex, flags, error);
+
+    lex_close(&lex);
+    return result;
+}
diff --git a/RedfishPkg/Library/JsonLib/math.h b/RedfishPkg/Library/JsonLib/math.h
new file mode 100644
index 0000000000..9a478c0f8a
--- /dev/null
+++ b/RedfishPkg/Library/JsonLib/math.h
@@ -0,0 +1,16 @@
+/** @file
+  Include file to support building the third-party jansson library.
+
+ Copyright (c) 2019, Intel Corporation. All rights reserved.<BR>
+ (C) Copyright 2020 Hewlett Packard Enterprise Development LP<BR>
+
+    SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#ifndef JANSSON_CRT_MATH_H_
+#define JANSSON_CRT_MATH_H_
+
+#include <JanssonCrtLibSupport.h>
+
+#endif
diff --git a/RedfishPkg/Library/JsonLib/stdarg.h b/RedfishPkg/Library/JsonLib/stdarg.h
new file mode 100644
index 0000000000..868fcd5cca
--- /dev/null
+++ b/RedfishPkg/Library/JsonLib/stdarg.h
@@ -0,0 +1,15 @@
+/** @file
+  Include file to support building the third-party jansson library.
+
+ Copyright (c) 2019, Intel Corporation. All rights reserved.<BR>
+ (C) Copyright 2020 Hewlett Packard Enterprise Development LP<BR>
+
+    SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+#ifndef JANSSON_CRT_STDARG_H_
+#define JANSSON_CRT_STDARG_H_
+
+#include <JanssonCrtLibSupport.h>
+
+#endif
diff --git a/RedfishPkg/Library/JsonLib/stddef.h b/RedfishPkg/Library/JsonLib/stddef.h
new file mode 100644
index 0000000000..8250f280b3
--- /dev/null
+++ b/RedfishPkg/Library/JsonLib/stddef.h
@@ -0,0 +1,16 @@
+/** @file
+  Include file to support building the third-party jansson library.
+
+ Copyright (c) 2019, Intel Corporation. All rights reserved.<BR>
+ (C) Copyright 2020 Hewlett Packard Enterprise Development LP<BR>
+
+    SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#ifndef JANSSON_CRT_STDDEF_H_
+#define JANSSON_CRT_STDDEF_H_
+
+#include <JanssonCrtLibSupport.h>
+
+#endif
diff --git a/RedfishPkg/Library/JsonLib/stdio.h b/RedfishPkg/Library/JsonLib/stdio.h
new file mode 100644
index 0000000000..5aa15b969f
--- /dev/null
+++ b/RedfishPkg/Library/JsonLib/stdio.h
@@ -0,0 +1,15 @@
+/** @file
+  Include file to support building the third-party jansson library.
+
+ Copyright (c) 2019, Intel Corporation. All rights reserved.<BR>
+ (C) Copyright 2020 Hewlett Packard Enterprise Development LP<BR>
+
+    SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+#ifndef JANSSON_CRT_STDIO_H_
+#define JANSSON_CRT_STDIO_H_
+
+#include <JanssonCrtLibSupport.h>
+
+#endif
diff --git a/RedfishPkg/Library/JsonLib/stdlib.h b/RedfishPkg/Library/JsonLib/stdlib.h
new file mode 100644
index 0000000000..dfbfd85655
--- /dev/null
+++ b/RedfishPkg/Library/JsonLib/stdlib.h
@@ -0,0 +1,16 @@
+/** @file
+  Include file to support building the third-party jansson library.
+
+ Copyright (c) 2019, Intel Corporation. All rights reserved.<BR>
+ (C) Copyright 2020 Hewlett Packard Enterprise Development LP<BR>
+
+    SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#ifndef JANSSON_CRT_STDLIB_H_
+#define JANSSON_CRT_STDLIB_H_
+
+#include <JanssonCrtLibSupport.h>
+
+#endif
diff --git a/RedfishPkg/Library/JsonLib/string.h b/RedfishPkg/Library/JsonLib/string.h
new file mode 100644
index 0000000000..691de583a3
--- /dev/null
+++ b/RedfishPkg/Library/JsonLib/string.h
@@ -0,0 +1,16 @@
+/** @file
+  Include file to support building the third-party jansson library.
+
+ Copyright (c) 2019, Intel Corporation. All rights reserved.<BR>
+ (C) Copyright 2020 Hewlett Packard Enterprise Development LP<BR>
+
+    SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#ifndef JANSSON_CRT_STRING_H_
+#define JANSSON_CRT_STRING_H_
+
+#include <JanssonCrtLibSupport.h>
+
+#endif
diff --git a/RedfishPkg/Library/JsonLib/sys/time.h b/RedfishPkg/Library/JsonLib/sys/time.h
new file mode 100644
index 0000000000..5039c1991c
--- /dev/null
+++ b/RedfishPkg/Library/JsonLib/sys/time.h
@@ -0,0 +1,15 @@
+/** @file
+  Include file to support building the third-party jansson library.
+
+ Copyright (c) 2019, Intel Corporation. All rights reserved.<BR>
+ (C) Copyright 2020 Hewlett Packard Enterprise Development LP<BR>
+
+    SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+#ifndef JANSSON_CRT_SYS_TIME_H_
+#define JANSSON_CRT_SYS_TIME_H_
+
+#include <JanssonCrtLibSupport.h>
+
+#endif
diff --git a/RedfishPkg/Library/JsonLib/sys/types.h b/RedfishPkg/Library/JsonLib/sys/types.h
new file mode 100644
index 0000000000..f2e23cf82f
--- /dev/null
+++ b/RedfishPkg/Library/JsonLib/sys/types.h
@@ -0,0 +1,15 @@
+/** @file
+  Include file to support building the third-party jansson library.
+
+ Copyright (c) 2019, Intel Corporation. All rights reserved.<BR>
+ (C) Copyright 2020 Hewlett Packard Enterprise Development LP<BR>
+
+    SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+#ifndef JANSSON_CRT_SYS_TYPES_H_
+#define JANSSON_CRT_SYS_TYPES_H_
+
+#include <JanssonCrtLibSupport.h>
+
+#endif
diff --git a/RedfishPkg/Library/JsonLib/time.h b/RedfishPkg/Library/JsonLib/time.h
new file mode 100644
index 0000000000..dd05279b24
--- /dev/null
+++ b/RedfishPkg/Library/JsonLib/time.h
@@ -0,0 +1,15 @@
+/** @file
+  Include file to support building the third-party jansson library.
+
+ Copyright (c) 2019, Intel Corporation. All rights reserved.<BR>
+ (C) Copyright 2020 Hewlett Packard Enterprise Development LP<BR>
+
+    SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+#ifndef JANSSON_CRT_TIME_H_
+#define JANSSON_CRT_TIME_H_
+
+#include <JanssonCrtLibSupport.h>
+
+#endif
diff --git a/RedfishPkg/RedfishPkg.ci.yaml b/RedfishPkg/RedfishPkg.ci.yaml
index 20c297ad22..78c2814d04 100644
--- a/RedfishPkg/RedfishPkg.ci.yaml
+++ b/RedfishPkg/RedfishPkg.ci.yaml
@@ -17,6 +17,30 @@
         ],
         ## Both file path and directory path are accepted.
         "IgnoreFiles": [
+            ## Below are files incorporated with open source which are
+            ## not edk2 coding standard compliant.
+            ##
+            ## For jansson library open source
+            ## load.c is overrided from open source.
+            "Library/JsonLib/load.c",
+            ## EDKII JsonLib API to jansson API mapping definitions.
+            "Include/Library/JanssonJsonLibMapping.h",
+            ## C runtime library for EDKII JsonLib.
+            "Library/JsonLib/sys",
+            "Library/JsonLib/JanssonCrtLibSupport.c",
+            "Library/JsonLib/JanssonCrtLibSupport.h",
+            "Library/JsonLib/assert.h",
+            "Library/JsonLib/errno.h",
+            "Library/JsonLib/jansson_config.h",
+            "Library/JsonLib/jansson_private_config.h",
+            "Library/JsonLib/limits.h",
+            "Library/JsonLib/math.h",
+            "Library/JsonLib/stdarg.h",
+            "Library/JsonLib/stddef.h",
+            "Library/JsonLib/stdio.h",
+            "Library/JsonLib/stdlib.h",
+            "Library/JsonLib/string.h",
+            "Library/JsonLib/time.h"
         ]
     },
     "CompilerPlugin": {
@@ -50,7 +74,14 @@
         "IgnoreFoldersAndFiles": []
     },
     "LibraryClassCheck": {
-        "IgnoreHeaderFile": []
+        "IgnoreHeaderFile": [
+            ## Below header file can be used by open source
+            ## project which uses jansson library. Use this
+            ## header file to map jansson native APIs to
+            ## edk2 JsonLib APIs.This header file doesn't
+            ## have the corresponding library class.
+            "Include/Library/JanssonJsonLibMapping.h"
+        ]
     },
 
     ## options defined ci/Plugin/SpellCheck
-- 
2.17.1



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