json_parameters.F90 Source File

!*****************************************************************************************
!> author: Jacob Williams
!  license: BSD
!
!  Other parameters used by JSON-Fortran.
!  This is a low-level module not meant to be used by a JSON-Fortran user.
!
!## License
!  * JSON-Fortran is released under a BSD-style license.
!    See the [LICENSE](https://github.com/jacobwilliams/json-fortran/blob/master/LICENSE)
!    file for details.

    module json_parameters

    use json_kinds

    implicit none

    public

    character(kind=CDK,len=*),parameter :: json_ext = '.json'   !! JSON file extension

    !special JSON characters
    character(kind=CK,len=*),parameter :: space           = ' '
    character(kind=CK,len=*),parameter :: start_object    = '{'
    character(kind=CK,len=*),parameter :: end_object      = '}'
    character(kind=CK,len=*),parameter :: start_array     = '['
    character(kind=CK,len=*),parameter :: end_array       = ']'
    character(kind=CK,len=*),parameter :: delimiter       = ','
    character(kind=CK,len=*),parameter :: colon_char      = ':'
    character(kind=CK,len=*),parameter :: start_array_alt = '('  !! for [[json_get_by_path]]
    character(kind=CK,len=*),parameter :: end_array_alt   = ')'  !! for [[json_get_by_path]]
    character(kind=CK,len=*),parameter :: root            = '$'  !! for [[json_get_by_path]]
    character(kind=CK,len=*),parameter :: this            = '@'  !! for [[json_get_by_path]]
    character(kind=CK,len=*),parameter :: child           = '.'  !! for [[json_get_by_path]]
    character(kind=CK,len=*),parameter :: bspace          = achar(8)
    character(kind=CK,len=*),parameter :: horizontal_tab  = achar(9)
    character(kind=CK,len=*),parameter :: newline         = achar(10)
    character(kind=CK,len=*),parameter :: formfeed        = achar(12)
    character(kind=CK,len=*),parameter :: carriage_return = achar(13)
    character(kind=CK,len=*),parameter :: quotation_mark  = achar(34)
    character(kind=CK,len=*),parameter :: slash           = achar(47)
    character(kind=CK,len=*),parameter :: backslash       = achar(92)

    character(kind=CDK,len=*),parameter,public :: default_real_fmt = '(ss,E26.16E4)'
        !! default real number format statement (for writing real values to strings and files).
        !! Note that this can be overridden by calling [[json_initialize]].

    character(kind=CK,len=*),parameter,public :: star = '*' !! for invalid numbers and
                                                            !! list-directed real output

#if defined __GFORTRAN__
    !not parameters due to gfortran bug (https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65141)
    character(kind=CK,len=26),protected :: upper = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ' !! uppercase characters
    character(kind=CK,len=26),protected :: lower = 'abcdefghijklmnopqrstuvwxyz' !! lowercase characters
#else
    character(kind=CK,len=*),parameter,public :: upper = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ' !! uppercase characters
    character(kind=CK,len=*),parameter,public :: lower = 'abcdefghijklmnopqrstuvwxyz' !! lowercase characters
#endif

#if defined __GFORTRAN__
    !not parameters due to gfortran bug (https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65141)
    character(kind=CK,len=4),protected :: null_str  = 'null'  !! JSON Null variable string
    character(kind=CK,len=4),protected :: true_str  = 'true'  !! JSON logical True string
    character(kind=CK,len=5),protected :: false_str = 'false' !! JSON logical False string
#else
    character(kind=CK,len=*),parameter,public :: null_str  = 'null'  !! JSON Null variable string
    character(kind=CK,len=*),parameter,public :: true_str  = 'true'  !! JSON logical True string
    character(kind=CK,len=*),parameter,public :: false_str = 'false' !! JSON logical False string
#endif

    integer, private :: i_      !! just a counter for `control_chars` array
    character(kind=CK,len=*),dimension(32),parameter :: control_chars = &
        [(achar(i_),i_=1,31), achar(127)] !! Control characters, possibly in unicode

    !find out the precision of the floating point number system
    !and set safety factors
    integer(IK),parameter :: rp_safety_factor = 1_IK
    integer(IK),parameter :: rp_addl_safety = 1_IK
    integer(IK),parameter :: real_precision = rp_safety_factor*precision(1.0_RK) + &
                                              rp_addl_safety

    !Get the number of possible digits in the exponent when using decimal number system
    integer(IK),parameter :: maxexp = maxexponent(1.0_RK)
    integer(IK),parameter :: minexp = minexponent(1.0_RK)
    integer(IK),parameter :: real_exponent_digits = floor( 1 + log10( &
                                  real(max(maxexp,abs(maxexp)),&
                                  kind=RK) ) )

    integer(IK),parameter :: max_numeric_str_len = real_precision + real_exponent_digits + 6
        !! 6 = sign + leading 0 + decimal + 'E' + exponent sign + 1 extra
    character(kind=CDK,len=*),parameter :: int_fmt  = '(ss,I0)' !! minimum width format for integers

    integer(IK),parameter :: chunk_size = 100_IK  !! for allocatable strings: allocate chunks of this size
    integer(IK),parameter :: unit2str = -1_IK  !! unit number to cause stuff to be
                                               !! output to strings rather than files.
                                               !! See 9.5.6.12 in the F2003/08 standard

    integer(IK),parameter,public :: seq_chunk_size = 256_IK !! chunk size for reading sequential files

    integer(IK),parameter,public :: pushed_char_size = 10_IK !! magic number

    end module json_parameters
!*****************************************************************************************