unit b_utils

Common Utils

author: bocianu bocianu@gmail.com

Set of useful procedures to simplify common tasks in Atari 8-bit programming.
This library is a part of 'blibs' - set of custom Mad-Pascal libraries.
https://gitlab.com/bocianu/blibs

Types:

name:	type:	description:
TdateTime	record year: word; month: byte; day: byte; // day of month hour: byte; minute: byte; second: byte; dow: byte; // day of week end;	Record type used to store date and time.

Interface:

name:	description:
CountBits	function CountBits(b: byte):byte;assembler; Counts number of ones in bits of any byte value. parameters: b - byte value to count bits in returns: (byte) - number fo bits turned on
WriteLnCentered	procedure WriteLnCentered(s: string); Outputs string aligned to center of screen width. Length of string should not exceed screen width (40). parameters: s - string to write
WriteRightAligned	procedure WriteRightAligned(w: byte; s: TString); Outputs string aligned to right of provided width. Length of string should not exceed provided width of field. parameters: w - width of field to align s - string to write
NullTermToString	function NullTermToString(ptr: word): string; Parses null terminated string into regular pascal string variable. parameters: ptr (word) - address in memory of null terminated string returns: (string) - regular pascal string type variable
FFTermToString	function FFTermToString(ptr: word): string; Parses string terminated with $FF into regular pascal string variable. parameters: ptr (word) - address in memory of null terminated string returns: (string) - regular pascal string type variable
ExpandRLE	procedure ExpandRLE(src: word; dest: word); Expands RLE compressed data from source memory location and writes expanded data at destination memory address. parameters: src (word) - source address of compressed data dest (word) - destination address where data is expanded
ExpandLZ4	procedure ExpandLZ4(source: word; dest: word);assembler; Expands LZ4 compressed data from source memory location and writes expanded data at destination memory address. Based on xxl & fox routine from here: https://xxl.atari.pl/lz4-decompressor/ parameters: src (word) - source address of compressed data dest (word) - destination address where data is expanded
UnixToDate	procedure UnixToDate(ux: cardinal; var date: TDateTime); Converts unix timestamp to proper date, represented as an record of TDateTime type. parameters: ux (cardinal) - unix timestamp date (TDateTime) - record where the result of conversion is stored
Hour24to12	function Hour24to12(hour: byte):byte; Converts 24 hour clock indication into to 12 hour parameters: hour (byte) - hour (0-23) returns: (byte) - hour(0-12)
HexChar2Dec	function HexChar2Dec(c:char):byte; Converts hex char into proper value in decimal. parameters: c (char) - hex char (0-9,a-f) returns: (byte) - decimal value (0-15), on error (invalid char) returns 255
Base64Init	procedure Base64Init; Initializes base64 encoding tables. Must be started once, prior to any compression or decompression process.
Base64Encode	procedure Base64Encode(var src, dest: string); Encodes string using base64 code. Be sure that trlaslation arrays are initialized by calling Base64Init first. Once. parameters: src (string) - source string dest (string) - destination string where data is encoded
Base64Decode	procedure Base64Decode(var src, dest: string); Decodes base 64 encoded string Be sure that trlaslation arrays are initialized by calling Base64Init first. Once. parameters: src (string) - encoded source string dest (string) - destination string where data is decoded