text: /** @file
    CRT wrapper functions for system call,the string operation functions
    are remodeled after edk2-libc.
  
    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 <Uefi.h>
  #include <Library/RedfishCrtLib.h>
  #include <Library/MemoryAllocationLib.h>
  #include <Library/SortLib.h>
  #include <Library/UefiRuntimeServicesTableLib.h>
  
  int   errno            = 0;
  char  errnum_message[] = "We don't support to map errnum to the error message on edk2 Redfish\n";
  
  // This is required to keep VC++ happy if you use floating-point
  int  _fltused = 1;
  
  /**
    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
    )
  {
    DEBUG ((DEBUG_INFO, "We don't supprot double type on edk2 yet!"));
    ASSERT (FALSE);
    return (double)0;
  }
  
  static UINT8  BitMask[] = {
    0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80
  };
  
  #define WHICH8(c)     ((unsigned char)(c) >> 3)
  #define WHICH_BIT(c)  (BitMask[((c) & 0x7)])
  #define BITMAP64  ((UINT64 *)bitmap)
  
  static
  void
  BuildBitmap (
    unsigned char  *bitmap,
    const char     *s2,
    int            n
    )
  {
    unsigned char  bit;
    int            index;
  
    // Initialize bitmap.  Bit 0 is always 1 which corresponds to '\0'
    for (BITMAP64[0] = index = 1; index < n; index++) {
      BITMAP64[index] = 0;
    }
  
    // Set bits in bitmap corresponding to the characters in s2
    for ( ; *s2 != '\0'; s2++) {
      index         = WHICH8 (*s2);
      bit           = WHICH_BIT (*s2);
      bitmap[index] = bitmap[index] | bit;
    }
  }
  
  /** The strpbrk function locates the first occurrence in the string pointed to
      by s1 of any character from the string pointed to by s2.
  
      @return   The strpbrk function returns a pointer to the character, or a
                null pointer if no character from s2 occurs in s1.
  **/
  char *
  strpbrk (
    const char  *s1,
    const char  *s2
    )
  {
    UINT8  bitmap[(((UCHAR_MAX + 1) / CHAR_BIT) + (CHAR_BIT - 1)) & ~7U];
    UINT8  bit;
    int    index;
  
    BuildBitmap (bitmap, s2, sizeof (bitmap) / sizeof (UINT64));
  
    for ( ; *s1 != '\0'; ++s1) {
      index = WHICH8 (*s1);
      bit   = WHICH_BIT (*s1);
      if ((bitmap[index] & bit) != 0) {
        return (char *)s1;
      }
    }
  
    return NULL;
  }
  
  /** The strerror function maps the number in errnum to a message string.
      Typically, the values for errnum come from errno, but strerror shall map
      any value of type int to a message.
  
      The implementation shall behave as if no library function calls the
      strerror function.
  
      @return   The strerror function returns a pointer to the string, the
                contents of which are locale specific.  The array pointed to
                shall not be modified by the program, but may be overwritten by
                a subsequent call to the strerror function.
  **/
  char *
  strerror (
    int  errnum
    )
  {
    return errnum_message;
  }
  
  /**
    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;
  }
  
  /**
    Performs a quick sort
  **/
  void
  qsort (
    void *base,
    size_t num,
    size_t width,
    int ( *compare )(const void *, const void *)
    )
  {
    ASSERT (base    != NULL);
    ASSERT (compare != NULL);
  
    PerformQuickSort (base, (UINTN)num, (UINTN)width, (SORT_COMPARE)compare);
    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 EOF;
  }
  
  /**
    Open stream file, we don't support file operastion on edk2 JSON library.
  
    @return 0 Unsupported
  
  **/
  FILE *
  fopen (
    const char  *filename,
    const char  *mode
    )
  {
    return NULL;
  }
  
  /**
    Read stream from file, we don't support file operastion on edk2 JSON library.
  
    @return 0 Unsupported
  
  **/
  size_t
  fread (
    void    *ptr,
    size_t  size,
    size_t  count,
    FILE    *stream
    )
  {
    return 0;
  }
  
  /**
    Write stream from file, we don't support file operastion on edk2 JSON library.
  
    @return 0 Unsupported
  
  **/
  size_t
  fwrite (
    const void  *ptr,
    size_t      size,
    size_t      count,
    FILE        *stream
    )
  {
    return 0;
  }
  
  /**
    Close file, we don't support file operastion on edk2 JSON library.
  
    @return 0 Unsupported
  
  **/
  int
  fclose (
    FILE  *stream
    )
  {
    return EOF;
  }
  
  /**
    Write the formatted string to file, we don't support file operastion on edk2 JSON library.
  
    @return 0 Unsupported
  
  **/
  int
  fprintf (
    FILE        *stream,
    const char  *format,
    ...
    )
  {
    return -1;
  }
  
  /**
    This function check if this is the formating string specifier.
  
    @param[in]      FormatString     A Null-terminated ASCII format string.
    @param[in,out]  CurrentPosition  The starting position at the given string to check for
                                     "[flags][width][.precision][length]s" string specifier.
    @param[in]      StrLength        Maximum string length.
  
    @return BOOLEAN   TRUE means this is the formating string specifier. CurrentPosition is
                      returned at the position of "s".
                      FALSE means this is not the formating string specifier.. CurrentPosition is
                      returned at the position of failed character.
  
  **/
  BOOLEAN
  CheckFormatingString (
    IN     CONST CHAR8  *FormatString,
    IN OUT UINTN        *CurrentPosition,
    IN     UINTN        StrLength
    )
  {
    CHAR8  FormatStringParamater;
  
    while (*(FormatString + *CurrentPosition) != 's') {
      //
      // Loop until reach character 's' if the formating string is
      // compliant with "[flags][width][.precision][length]" format for
      // the string specifier.
      //
      FormatStringParamater = *(FormatString + *CurrentPosition);
      if ((FormatStringParamater != '-') &&
          (FormatStringParamater != '+') &&
          (FormatStringParamater != '*') &&
          (FormatStringParamater != '.') &&
          !(((UINTN)FormatStringParamater >= (UINTN)'0') && ((UINTN)FormatStringParamater <= (UINTN)'9'))
          )
      {
        return FALSE;
      }
  
      (*CurrentPosition)++;
      if (*CurrentPosition >= StrLength) {
        return FALSE;
      }
    }
  
    return TRUE;
  }
  
  /**
    This function clones *FormatString however replaces "%s" with "%a" in the
    returned string.
  
    @param[in] A Null-terminated ASCII format string.
  
    @return The new format string. Caller has to free the memory of this string
            using FreePool().
  
  **/
  CHAR8 *
  ReplaceUnicodeToAsciiStrFormat (
    IN CONST CHAR8  *FormatString
    )
  {
    UINTN    FormatStrSize;
    UINTN    FormatStrIndex;
    UINTN    FormatStrSpecifier;
    BOOLEAN  PercentageMark;
    CHAR8    *TempFormatBuffer;
    BOOLEAN  IsFormatString;
  
    //
    // Error checking.
    //
    if (FormatString == NULL) {
      return NULL;
    }
  
    FormatStrSize = AsciiStrSize (FormatString);
    if (FormatStrSize == 0) {
      return NULL;
    }
  
    TempFormatBuffer = AllocatePool (FormatStrSize); // Allocate memory for the
                                                     // new string.
    if (TempFormatBuffer == NULL) {
      return NULL;
    }
  
    //
    // Clone *FormatString but replace "%s" wih "%a".
    // "%%" is not considered as the format tag.
    //
    PercentageMark = FALSE;
    FormatStrIndex = 0;
    while (FormatStrIndex < FormatStrSize) {
      if (PercentageMark == TRUE) {
        //
        // Previous character is "%".
        //
        PercentageMark = FALSE;
        if (*(FormatString + FormatStrIndex) != '%') {
          // Check if this is double "%".
          FormatStrSpecifier = FormatStrIndex;
          //
          // Check if this is the formating string specifier.
          //
          IsFormatString = CheckFormatingString (FormatString, &FormatStrSpecifier, FormatStrSize);
          if ((FormatStrSpecifier - FormatStrIndex) != 0) {
            CopyMem (
              (VOID *)(TempFormatBuffer + FormatStrIndex),
              (VOID *)(FormatString + FormatStrIndex),
              FormatStrSpecifier - FormatStrIndex
              );
          }
  
          FormatStrIndex = FormatStrSpecifier;
          if (IsFormatString == TRUE) {
            //
            // Replace 's' with 'a' which is printed in ASCII
            // format on edk2 environment.
            //
            *(TempFormatBuffer + FormatStrSpecifier) = 'a';
            FormatStrIndex++;
          }
  
          continue;
        }
  
        goto ContinueCheck;
      }
  
      if (*(FormatString + FormatStrIndex) == '%') {
        //
        // This character is "%", set the flag.
        //
        PercentageMark = TRUE;
      }
  
  ContinueCheck:
      //
      // Clone character to the new string and advance FormatStrIndex
      // to process next character.
      //
      *(TempFormatBuffer + FormatStrIndex) = *(FormatString + FormatStrIndex);
      FormatStrIndex++;
    }
  
    return TempFormatBuffer;
  }
  
  /**
    This is the Redfish version of CRT vsnprintf function, this function replaces "%s" to
    "%a" before invoking AsciiVSPrint(). That is because "%s" is unicode base on edk2
    environment however "%s" is ascii code base on vsnprintf().
    See definitions of AsciiVSPrint() for the details.
  
    @param  StartOfBuffer   A pointer to the output buffer for the produced Null-terminated
                            ASCII string.
    @param  BufferSize      The size, in bytes, of the output buffer specified by StartOfBuffer.
    @param  FormatString    A Null-terminated ASCII format string.
    @param  Marker          VA_LIST marker for the variable argument list.
  
    @return The number of ASCII characters in the produced output buffer not including the
            Null-terminator.
  
  **/
  UINTN
  EFIAPI
  RedfishAsciiVSPrint (
    OUT CHAR8        *StartOfBuffer,
    IN  UINTN        BufferSize,
    IN  CONST CHAR8  *FormatString,
    IN  VA_LIST      Marker
    )
  {
    CHAR8  *TempFormatBuffer;
    UINTN  LenStrProduced;
  
    //
    // Looking for "%s" in the format string and replace it
    // with "%a" for printing ASCII code characters on edk2
    // environment.
    //
    TempFormatBuffer = ReplaceUnicodeToAsciiStrFormat (FormatString);
    if (TempFormatBuffer == NULL) {
      return 0;
    }
  
    LenStrProduced = AsciiVSPrint (StartOfBuffer, BufferSize, (CONST CHAR8 *)TempFormatBuffer, Marker);
    FreePool (TempFormatBuffer);
    return LenStrProduced;
  }
  
  /**
    This is the Redfish version of CRT snprintf function, this function replaces "%s" to
    "%a" before invoking AsciiSPrint(). That is because "%s" is unicode base on edk2
    environment however "%s" is ascii code base on snprintf().
    See definitions of AsciiSPrint() for the details.
  
    @param  StartOfBuffer   A pointer to the output buffer for the produced Null-terminated
                            ASCII string.
    @param  BufferSize      The size, in bytes, of the output buffer specified by StartOfBuffer.
    @param  FormatString    A Null-terminated ASCII format string.
    @param  ...             Variable argument list whose contents are accessed based on the
                            format string specified by FormatString.
  
    @return The number of ASCII characters in the produced output buffer not including the
            Null-terminator.
  
  **/
  UINTN
  EFIAPI
  RedfishAsciiSPrint (
    OUT CHAR8        *StartOfBuffer,
    IN  UINTN        BufferSize,
    IN  CONST CHAR8  *FormatString,
    ...
    )
  {
    VA_LIST  Marker;
    UINTN    LenStrProduced;
  
    VA_START (Marker, FormatString);
    LenStrProduced = RedfishAsciiVSPrint (StartOfBuffer, BufferSize, FormatString, Marker);
    return LenStrProduced;
  }
  