parse_string Subroutine

private subroutine parse_string(json, unit, str, string)

Parses a string while reading a JSON file.

History

  • Jacob Williams : 6/16/2014 : Added hex validation.
  • Jacob Williams : 12/3/2015 : Fixed some bugs.
  • Jacob Williams : 8/23/2015 : string is now returned unescaped.

Arguments

Type IntentOptional AttributesName
class(json_core), intent(inout) :: json
integer(kind=IK), intent(in) :: unit

file unit number (if parsing from a file)

character(kind=CK,len=*), intent(in) :: str

JSON string (if parsing from a string)

character(kind=CK,len=:), intent(out), allocatable:: string

the string (unescaped if necessary)

Calls

proc~~parse_string~~CallsGraph proc~parse_string parse_string proc~valid_json_hex valid_json_hex proc~parse_string->proc~valid_json_hex proc~unescape_string unescape_string proc~parse_string->proc~unescape_string interface~to_unicode to_unicode proc~unescape_string->interface~to_unicode proc~to_uni_vec to_uni_vec interface~to_unicode->proc~to_uni_vec proc~to_uni to_uni interface~to_unicode->proc~to_uni
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Source Code


Source Code

    subroutine parse_string(json, unit, str, string)

    implicit none

    class(json_core),intent(inout)                   :: json
    integer(IK),intent(in)                           :: unit  !! file unit number (if parsing from a file)
    character(kind=CK,len=*),intent(in)              :: str   !! JSON string (if parsing from a string)
    character(kind=CK,len=:),allocatable,intent(out) :: string !! the string (unescaped if necessary)

    logical(LK) :: eof, is_hex, escape
    character(kind=CK,len=1) :: c
    character(kind=CK,len=4) :: hex
    integer(IK) :: i
    integer(IK) :: ip !! index to put next character,
                      !! to speed up by reducing the number of character string reallocations.
    character(kind=CK,len=:),allocatable :: string_unescaped !! temp variable
    character(kind=CK,len=:),allocatable :: error_message !! for string unescaping

    !at least return a blank string if there is a problem:
    string = repeat(space, chunk_size)

    if (.not. json%exception_thrown) then

        !initialize:
        ip     = 1
        is_hex = .false.
        escape = .false.
        i      = 0

        do

            !get the next character from the file:
            call json%pop_char(unit, str=str, eof=eof, skip_ws=.false., popped=c)

            if (eof) then

                call json%throw_exception('Error in parse_string: Expecting end of string')
                return

            else if (c==quotation_mark .and. .not. escape) then  !end of string

                if (is_hex) call json%throw_exception('Error in parse_string:'//&
                                                 ' incomplete hex string: \u'//trim(hex))
                exit

            else

                !if the string is not big enough, then add another chunk:
                if (ip>len(string)) string = string // repeat(space, chunk_size)

                !append to string:
                string(ip:ip) = c
                ip = ip + 1

                !hex validation:
                if (is_hex) then  !accumulate the four characters after '\u'

                    i=i+1
                    hex(i:i) = c
                    if (i==4) then
                        if (valid_json_hex(hex)) then
                            i = 0
                            hex = CK_''
                            is_hex = .false.
                        else
                            call json%throw_exception('Error in parse_string:'//&
                                                 ' invalid hex string: \u'//trim(hex))
                            exit
                        end if
                    end if

                else

                    !when the '\u' string is encountered, then
                    !  start accumulating the hex string (should be the next 4 characters)
                    if (escape) then
                        escape = .false.
                        is_hex = (c=='u')    !the next four characters are the hex string
                    else
                        escape = (c==backslash)
                    end if

                end if

            end if

        end do

        !trim the string if necessary:
        if (ip<len(string)+1) then
            if (ip==1) then
                string = CK_''
            else
                string = string(1:ip-1)
            end if
        end if

        !string is returned unescaped:
        call unescape_string(string,string_unescaped,error_message)
        if (allocated(error_message)) then
            call json%throw_exception(error_message)
        else
            string = string_unescaped
        end if

        !cleanup:
        if (allocated(error_message))    deallocate(error_message)
        if (allocated(string_unescaped)) deallocate(string_unescaped)

    end if

    end subroutine parse_string


annotate_invalid_json compact_real_string convert decode_rfc6901 default_comp_ucs4 default_join_ucs4 default_neq_ucs4 destroy_json_core destroy_json_data encode_rfc6901 escape_string get_current_line_from_file_sequential get_current_line_from_file_stream get_json_core_in_file initialize_json_core initialize_json_core_in_file initialize_json_file initialize_json_file_v2 integer_to_string json_add_double_by_path json_add_double_vec_by_path json_add_integer_by_path json_add_integer_vec_by_path json_add_logical_by_path json_add_logical_vec_by_path json_add_member_by_path json_add_string_by_path json_add_string_by_path_path_ascii json_add_string_by_path_value_ascii json_add_string_vec_by_path json_add_string_vec_by_path_path_ascii json_add_string_vec_by_path_value_ascii json_check_all_for_duplicate_keys json_check_children_for_duplicate_keys json_check_for_errors json_clear_exceptions json_clone json_core json_count json_create_by_path json_failed json_file json_file_add_double json_file_add_double_vec json_file_add_integer json_file_add_integer_vec json_file_add_logical json_file_add_logical_vec json_file_add_object json_file_add_string json_file_add_string_path_ascii json_file_add_string_value_ascii json_file_add_string_vec json_file_add_string_vec_path_ascii json_file_add_string_vec_vec_ascii json_file_check_for_errors json_file_clear_exceptions json_file_destroy json_file_failed json_file_get_alloc_string_vec json_file_get_double json_file_get_double_vec json_file_get_integer json_file_get_integer_vec json_file_get_logical json_file_get_logical_vec json_file_get_object json_file_get_root json_file_get_string json_file_get_string_vec json_file_load json_file_load_from_string json_file_move_pointer json_file_print_1 json_file_print_2 json_file_print_error_message json_file_print_to_console json_file_print_to_string json_file_traverse json_file_update_integer json_file_update_logical json_file_update_real json_file_update_string json_file_update_string_name_ascii json_file_update_string_val_ascii json_file_variable_info json_file_variable_matrix_info json_get_alloc_string_vec json_get_alloc_string_vec_by_path json_get_array json_get_array_by_path json_get_by_path json_get_by_path_default json_get_by_path_jsonpath_bracket json_get_by_path_rfc6901 json_get_double json_get_double_by_path json_get_double_vec json_get_double_vec_by_path json_get_integer json_get_integer_by_path json_get_integer_vec json_get_integer_vec_by_path json_get_logical json_get_logical_by_path json_get_logical_vec json_get_logical_vec_by_path json_get_next json_get_parent json_get_path json_get_previous json_get_string json_get_string_by_path json_get_string_vec json_get_string_vec_by_path json_get_tail json_info json_info_by_path json_initialize json_matrix_info json_matrix_info_by_path json_parse_file json_parse_string json_print_1 json_print_2 json_print_error_message json_string_info json_throw_exception json_traverse json_update_double json_update_integer json_update_logical json_update_string json_update_string_name_ascii json_update_string_val_ascii json_value_add_double json_value_add_double_vec json_value_add_integer json_value_add_integer_vec json_value_add_logical json_value_add_logical_vec json_value_add_member json_value_add_null json_value_add_string json_value_add_string_name_ascii json_value_add_string_val_ascii json_value_add_string_vec json_value_add_string_vec_name_ascii json_value_add_string_vec_val_ascii json_value_clone_func json_value_create json_value_create_array json_value_create_double json_value_create_integer json_value_create_logical json_value_create_null json_value_create_object json_value_create_string json_value_destroy json_value_get_child json_value_get_child_by_index json_value_get_child_by_name json_value_insert_after json_value_insert_after_child_by_index json_value_is_child_of json_value_print json_value_remove json_value_remove_if_present json_value_rename json_value_replace json_value_reverse json_value_swap json_value_to_string json_value_validate lowercase_string name_equal name_strings_equal parse_array parse_for_chars parse_number parse_object parse_string parse_value pop_char push_char real_to_string replace_string set_json_core_in_file string_to_dble string_to_int string_to_integer string_to_real to_array to_double to_integer to_logical to_null to_object to_string to_uni to_uni_vec to_unicode ucs4_comp_default ucs4_join_default ucs4_neq_default unescape_string valid_json_hex wrap_json_add_double_by_path wrap_json_add_double_vec_by_path wrap_json_add_integer_by_path wrap_json_add_integer_vec_by_path wrap_json_add_logical_by_path wrap_json_add_logical_vec_by_path wrap_json_add_member_by_path wrap_json_add_string_by_path wrap_json_add_string_vec_by_path wrap_json_create_by_path wrap_json_file_add_double wrap_json_file_add_double_vec wrap_json_file_add_integer wrap_json_file_add_integer_vec wrap_json_file_add_logical wrap_json_file_add_logical_vec wrap_json_file_add_object wrap_json_file_add_string wrap_json_file_add_string_vec wrap_json_file_get_alloc_string_vec wrap_json_file_get_double wrap_json_file_get_double_vec wrap_json_file_get_integer wrap_json_file_get_integer_vec wrap_json_file_get_logical wrap_json_file_get_logical_vec wrap_json_file_get_object wrap_json_file_get_string wrap_json_file_get_string_vec wrap_json_file_load_from_string wrap_json_file_update_integer wrap_json_file_update_logical wrap_json_file_update_real wrap_json_file_update_string wrap_json_file_variable_info wrap_json_file_variable_matrix_info wrap_json_get_alloc_string_vec_by_path wrap_json_get_array_by_path wrap_json_get_by_path wrap_json_get_double_by_path wrap_json_get_double_vec_by_path wrap_json_get_integer_by_path wrap_json_get_integer_vec_by_path wrap_json_get_logical_by_path wrap_json_get_logical_vec_by_path wrap_json_get_path wrap_json_get_string_by_path wrap_json_get_string_vec_by_path wrap_json_info_by_path wrap_json_matrix_info_by_path wrap_json_parse_string wrap_json_throw_exception wrap_json_update_double wrap_json_update_integer wrap_json_update_logical wrap_json_update_string wrap_json_value_add_double wrap_json_value_add_double_vec wrap_json_value_add_integer wrap_json_value_add_integer_vec wrap_json_value_add_logical wrap_json_value_add_logical_vec wrap_json_value_add_null wrap_json_value_add_string wrap_json_value_add_string_vec wrap_json_value_create_array wrap_json_value_create_double wrap_json_value_create_integer wrap_json_value_create_logical wrap_json_value_create_null wrap_json_value_create_object wrap_json_value_create_string wrap_json_value_get_child_by_name wrap_json_value_remove_if_present wrap_json_value_rename