Re: [edk2-devel] [PATCH v7 4/6] RedfishPkg/library: EDK2 port of jansson library

["Abner Chang" <abner.chang@hpe.com>]

> -----Original Message-----
> From: devel@edk2.groups.io [mailto:devel@edk2.groups.io] On Behalf Of
> Leif Lindholm
> Sent: Thursday, December 17, 2020 8:40 PM
> To: Chang, Abner (HPS SW/FW Technologist) <abner.chang@hpe.com>
> Cc: devel@edk2.groups.io; Wang, Nickle (HPS SW) <nickle.wang@hpe.com>;
> O'Hanley, Peter (EXL) <peter.ohanley@hpe.com>
> Subject: Re: [edk2-devel] [PATCH v7 4/6] RedfishPkg/library: EDK2 port of
> jansson library
> 
> On Wed, Dec 16, 2020 at 11:14:04 +0800, Abner Chang wrote:
> > edk2 JsonLib which is the edk2 port of open source jansson library.
> > (https://github.com/akheron/jansson)
> > jansson library is the open source project to manipulate JSON data
> > structure.
> >
> > Signed-off-by: Abner Chang <abner.chang@hpe.com>
> >
> > Cc: Leif Lindholm <leif@nuviainc.com>
> > Cc: Nickle Wang <nickle.wang@hpe.com>
> > Cc: Peter O'Hanley <peter.ohanley@hpe.com>
> > ---
> >  RedfishPkg/Include/Library/JsonLib.h          |  763 +++++++++++
> >  RedfishPkg/Library/JsonLib/JsonLib.c          |  964 ++++++++++++++
> >  RedfishPkg/Library/JsonLib/JsonLib.inf        |   89 ++
> >  RedfishPkg/Library/JsonLib/Readme.rst         |   40 +
> >  RedfishPkg/Library/JsonLib/jansson_config.h   |   41 +
> >  .../Library/JsonLib/jansson_private_config.h  |   19 +
> >  RedfishPkg/Library/JsonLib/load.c             | 1111 +++++++++++++++++
> >  RedfishPkg/RedfishPkg.ci.yaml                 |    8 +-
> >  RedfishPkg/RedfishPkg.dec                     |   11 +
> >  9 files changed, 3045 insertions(+), 1 deletion(-)
> 
> Please configure your git to use an orderfile for diffs.
> This can be done by running BaseTools/Scripts/SetupGit.py in your repository
> or manually by following
> https://github.com/tianocore/tianocore.github.io/wiki/Laszlo%27s-
> unkempt-git-guide-for-edk2-contributors-and-maintainers
Will check it, I thought I have that configured.
> 
> >  create mode 100644 RedfishPkg/Include/Library/JsonLib.h
> >  create mode 100644 RedfishPkg/Library/JsonLib/JsonLib.c
> >  create mode 100644 RedfishPkg/Library/JsonLib/JsonLib.inf
> >  create mode 100644 RedfishPkg/Library/JsonLib/Readme.rst
> >  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/load.c
> >
> 
> > 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@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
> 
> This is not accurate.
> You are adding the BSD-2-Clause-Patent license on top of the MIT license for
> this contribution. The statement should be
> 
>   SPDX-License-Identifier: BSD-2-Clause-Patent AND MIT
> 
> The way you're keeping the original header, then adding HPE copyright, and
> then adding the SPDX tag is ideal though. Makes it clear who did the license
> addition and when.
Leif, not quite sure which way is accurate, looks like below? Or could please you give me the right one? :)
Thanks

Copyright (c) 2009-2016 Petri Lehtinen <petri@digip.org>
(C) Copyright 2020 Hewlett Packard Enterprise Development LP<BR>

SPDX-License-Identifier: BSD-2-Clause-Patent AND MIT

> 
> /
>     Leif
> 
> > + */
> > +
> > +#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/RedfishPkg.ci.yaml
> > b/RedfishPkg/RedfishPkg.ci.yaml index 9895fdac99..2a26769536 100644
> > --- a/RedfishPkg/RedfishPkg.ci.yaml
> > +++ b/RedfishPkg/RedfishPkg.ci.yaml
> > @@ -35,7 +35,13 @@
> >              "Include/Crt/string.h",
> >              "Include/Crt/time.h",
> >              "Include/Library/CrtLib.h",
> > -            "Library/CrtLib/CrtLib.c"
> > +            "Library/CrtLib/CrtLib.c",
> > +            ##
> > +            ## For jansson library open source
> > +            ## load.c is overrided from open source.
> > +            "Library/JsonLib/load.c",
> > +            "Library/JsonLib/jansson_config.h",
> > +            "Library/JsonLib/jansson_private_config.h"
> >          ]
> >      },
> >      "CompilerPlugin": {
> > diff --git a/RedfishPkg/RedfishPkg.dec b/RedfishPkg/RedfishPkg.dec
> > index 9a9a1190fb..6499d77f3e 100644
> > --- a/RedfishPkg/RedfishPkg.dec
> > +++ b/RedfishPkg/RedfishPkg.dec
> > @@ -18,6 +18,12 @@
> >
> >  [Includes.Common.Private]
> >    Include/Crt                   # Header files for C RTL.
> > +  Library/JsonLib               # Header files for jansson configuration files.
> > +                                #  - jansson_config.h
> > +                                #  - jansson_private_config.h
> > +                                # jansson.h refers to above two configuration
> > +                                # files for building platform jansson library.
> > +  Library/JsonLib/jansson/src   # For referring to jannson.h
> >
> >  [LibraryClasses]
> >    ##  @libraryclass Platform Redfish Host Interface Library @@ -39,6
> > +45,11 @@
> >    #   project).
> >    CrtLib|Include/Library/CrtLib.h
> >
> > +  ##  @libraryclass  Provides the library functions based on third
> > + party  #  jansson library to manipulate JSON data structure.
> > +  #
> > +  JsonLib|Include/Library/JsonLib.h
> > +
> >  [Protocols]
> >    ## Include/Protocol/RedfishDiscover.h
> >    gEfiRedfishDiscoverProtocolGuid      = { 0x5db12509, 0x4550, 0x4347, { 0x96,
> 0xb3, 0x73, 0xc0, 0xff, 0x6e, 0x86, 0x9f }}
> > --
> > 2.17.1
> >
> 
> 
> 
>