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minisrv/zefie_wtvp_minisrv/WTVLzpf.js
zefie 6f2fa1d510 v0.9.16 
- numerous bug fixes
 - improve session retention
 - use wtv-head-waiter:/relogin for boot url
   - viewer seems to retain only wtv-* and wtv-head-waiter, so lets try to be closer to protocol and boot with a wtv-head-waiter address instead of wtv-1800
   - we still handle via wtv-1800 but we accept wtv-head-waiter:/relogin and send the client on its way to the relogin path
 - update wtv-home:/home
   - remove spacing in favor of right alignment
   - add compression status
 - guest mode session store update
   - allow calls to saveSessionData() but do not actually write if user is guest
   - saveSessionData() returns true even if guest, because false is meant to define an error
   - You can also use SaveIfRegistered(), this will return false on both saveSessionData() errors AND guest mode;
   - if you want to block guests, check for isRegistered() and block the request if it is false
   - otherwise this update will allow all tools (including any logins) to work with guest mode, but the stored SessionData will not be persistently saved, and lost when the cleanup timeout hits (default 3 min), or the server is restarted.
 - more accurately mimic WTVP by accepting URLs without /
 - use service-style cookie links on tricks
 - add catchall system & http pc server
   - define a catchall name to run globally or per service
   - catchall must be javascript, but not necessarily a .js file
   - catchall can request async mode
   - catchall will catch any non-existing requests under its directory
   - see wtv-flashrom:/content/content-serve.js as an example, which will catch wtv-flashrom:/content/ URLs.
 - http pc: sends HTTP/1.0 to PC clients
   - can be disabled with `pc_server_hidden_service_enabled`: false
   - can change servicevault path by changing string of pc_server_hidden_service
   - get.js in default PC service vault to get any WTV Url on the service
 - flashrom system updates
   - fix bugs
   - more WNI-like flow path
   - make scripts use `service_name` variable so that they should work in a renamed service (eg not wtv-flashrom, untested)
 - rewrite wtv-disk system
   - move wtv-update to wtv-disk
   - allow accessing wtv-disk:/sync?group=&diskmap=
   - rewrite Download List generation to be more proper
   - only send files if diskmap has changed
   - allow force redownload with &force=true
2022-11-29 08:27:57 -05:00

485 lines
19 KiB
JavaScript
Raw Blame History

/**
* Pure-JS implementation of WebTV's LZPF compression
*
* This is a port of my Lzpf compression code from my ROMFS Python tool
* Originally reverse engineered from the box
*
* By: Eric MacDonald (eMac)
* Modified By: zefie
*/
class WTVLzpf {
// Note: currentlty doesn't offer optimal streaming support but this is good enough to meet perf demands at the scale we're at.
current_length = 0;
current_literal = 0;
flag = 0xFFFF;
working_data = 0;
match_index = 0;
type_index = 0;
checksum = 0;
flag_table = new Uint16Array(0x1000)
ring_buffer = new Uint8Array(0x2000)
encoded_data = [];
nomatchEncode = [
[0x0000, 0x10], [0x0001, 0x10], [0x0002, 0x10],
[0x0003, 0x10], [0x0004, 0x10], [0x009A, 0x0F],
[0x0005, 0x10], [0x009C, 0x0F], [0x009E, 0x0F],
[0x3400, 0x06], [0x7000, 0x05], [0x00A0, 0x0F],
[0x0006, 0x10], [0x0380, 0x09], [0x0007, 0x10],
[0x0008, 0x10], [0x0009, 0x10], [0x000A, 0x10],
[0x000B, 0x10], [0x000C, 0x10], [0x000D, 0x10],
[0x000E, 0x10], [0x000F, 0x10], [0x00A2, 0x0F],
[0x0010, 0x10], [0x0011, 0x10], [0x0012, 0x10],
[0x0013, 0x10], [0x0014, 0x10], [0x0015, 0x10],
[0x0016, 0x10], [0x0017, 0x10], [0xE000, 0x04],
[0x0200, 0x0A], [0x7800, 0x05], [0x0400, 0x09],
[0x00B0, 0x0E], [0x0018, 0x10], [0x0120, 0x0B],
[0x0480, 0x09], [0x0140, 0x0B], [0x0160, 0x0B],
[0x0240, 0x0A], [0x00B8, 0x0D], [0x1400, 0x07],
[0x1600, 0x07], [0x3800, 0x06], [0x8000, 0x05],
[0x0A00, 0x08], [0x1800, 0x07], [0x0B00, 0x08],
[0x0500, 0x09], [0x0C00, 0x08], [0x0580, 0x09],
[0x0600, 0x09], [0x0680, 0x09], [0x0700, 0x09],
[0x0780, 0x09], [0x0D00, 0x08], [0x0180, 0x0B],
[0x8800, 0x05], [0x3C00, 0x06], [0x9000, 0x05],
[0x0280, 0x0A], [0x00B4, 0x0E], [0x4000, 0x06],
[0x1A00, 0x07], [0x1C00, 0x07], [0x1E00, 0x07],
[0x4400, 0x06], [0x2000, 0x07], [0x2200, 0x07],
[0x2400, 0x07], [0x4800, 0x06], [0x01A0, 0x0B],
[0x02C0, 0x0A], [0x2600, 0x07], [0x0E00, 0x08],
[0x4C00, 0x06], [0x5000, 0x06], [0x2800, 0x07],
[0x00C0, 0x0C], [0x5400, 0x06], [0x2A00, 0x07],
[0x9800, 0x05], [0x0800, 0x09], [0x0880, 0x09],
[0x0F00, 0x08], [0x00D0, 0x0C], [0x0300, 0x0A],
[0x0900, 0x09], [0x0019, 0x10], [0x001A, 0x10],
[0x001B, 0x10], [0x001C, 0x10], [0x1000, 0x08],
[0x001D, 0x10], [0xA000, 0x05], [0x2C00, 0x07],
[0x5800, 0x06], [0x5C00, 0x06], [0xF000, 0x04],
[0x2E00, 0x07], [0x3000, 0x07], [0x6000, 0x06],
[0xA800, 0x05], [0x01C0, 0x0B], [0x1100, 0x08],
[0x6400, 0x06], [0x6800, 0x06], [0xB000, 0x05],
[0xB800, 0x05], [0xC000, 0x05], [0x01E0, 0x0B],
[0xC800, 0x05], [0xD000, 0x05], [0xD800, 0x05],
[0x3200, 0x07], [0x1200, 0x08], [0x6C00, 0x06],
[0x0980, 0x09], [0x1300, 0x08], [0x0340, 0x0A],
[0x00E0, 0x0C], [0x00F0, 0x0C], [0x0100, 0x0C],
[0x0110, 0x0C], [0x001E, 0x10], [0x001F, 0x10],
[0x0020, 0x10], [0x0021, 0x10], [0x0022, 0x10],
[0x0023, 0x10], [0x0024, 0x10], [0x0025, 0x10],
[0x0026, 0x10], [0x0027, 0x10], [0x0028, 0x10],
[0x0029, 0x10], [0x002A, 0x10], [0x002B, 0x10],
[0x002C, 0x10], [0x002D, 0x10], [0x002E, 0x10],
[0x002F, 0x10], [0x00A4, 0x0F], [0x00A6, 0x0F],
[0x00A8, 0x0F], [0x0030, 0x10], [0x0031, 0x10],
[0x0032, 0x10], [0x0033, 0x10], [0x0034, 0x10],
[0x0035, 0x10], [0x0036, 0x10], [0x0037, 0x10],
[0x0038, 0x10], [0x0039, 0x10], [0x003A, 0x10],
[0x003B, 0x10], [0x003C, 0x10], [0x003D, 0x10],
[0x003E, 0x10], [0x003F, 0x10], [0x0040, 0x10],
[0x0041, 0x10], [0x0042, 0x10], [0x0043, 0x10],
[0x0044, 0x10], [0x0045, 0x10], [0x0046, 0x10],
[0x0047, 0x10], [0x0048, 0x10], [0x0049, 0x10],
[0x004A, 0x10], [0x004B, 0x10], [0x004C, 0x10],
[0x004D, 0x10], [0x004E, 0x10], [0x004F, 0x10],
[0x0050, 0x10], [0x0051, 0x10], [0x0052, 0x10],
[0x0053, 0x10], [0x0054, 0x10], [0x0055, 0x10],
[0x0056, 0x10], [0x0057, 0x10], [0x0058, 0x10],
[0x0059, 0x10], [0x005A, 0x10], [0x005B, 0x10],
[0x005C, 0x10], [0x005D, 0x10], [0x005E, 0x10],
[0x005F, 0x10], [0x0060, 0x10], [0x0061, 0x10],
[0x0062, 0x10], [0x00AA, 0x0F], [0x0063, 0x10],
[0x0064, 0x10], [0x0065, 0x10], [0x0066, 0x10],
[0x0067, 0x10], [0x0068, 0x10], [0x0069, 0x10],
[0x006A, 0x10], [0x006B, 0x10], [0x006C, 0x10],
[0x006D, 0x10], [0x006E, 0x10], [0x006F, 0x10],
[0x0070, 0x10], [0x0071, 0x10], [0x0072, 0x10],
[0x0073, 0x10], [0x0074, 0x10], [0x0075, 0x10],
[0x0076, 0x10], [0x0077, 0x10], [0x0078, 0x10],
[0x0079, 0x10], [0x007A, 0x10], [0x007B, 0x10],
[0x007C, 0x10], [0x007D, 0x10], [0x007E, 0x10],
[0x007F, 0x10], [0x0080, 0x10], [0x0081, 0x10],
[0x0082, 0x10], [0x0083, 0x10], [0x0084, 0x10],
[0x0085, 0x10], [0x0086, 0x10], [0x0087, 0x10],
[0x0088, 0x10], [0x0089, 0x10], [0x008A, 0x10],
[0x008B, 0x10], [0x008C, 0x10], [0x008D, 0x10],
[0x00AC, 0x0F], [0x008E, 0x10], [0x008F, 0x10],
[0x0090, 0x10], [0x0091, 0x10], [0x0092, 0x10],
[0x0093, 0x10], [0x00AE, 0x0F], [0x0094, 0x10],
[0x0095, 0x10], [0x0096, 0x10], [0x0097, 0x10],
[0x0098, 0x10], [0x0099, 0x10]
];
matchEncode = [
[0x80000000, 0x01], [0x80000000, 0x03],
[0xA0000000, 0x03], [0xC0000000, 0x03],
[0xE0000000, 0x06], [0xE4000000, 0x06],
[0xE8000000, 0x06], [0xEC000000, 0x06],
[0xF0000000, 0x06], [0xF4000000, 0x06],
[0xF8000000, 0x06], [0xFC000000, 0x0B],
[0xFC200000, 0x0B], [0xFC400000, 0x0B],
[0xFC600000, 0x0B], [0xFC800000, 0x0B],
[0xFCA00000, 0x0B], [0xFCC00000, 0x0B],
[0xFCE00000, 0x0B], [0xFD000000, 0x0B],
[0xFD200000, 0x0B], [0xFD400000, 0x0B],
[0xFD600000, 0x0B], [0xFD800000, 0x0B],
[0xFDA00000, 0x0B], [0xFDC00000, 0x0B],
[0xFDE00000, 0x0B], [0xFE000000, 0x0B],
[0xFE200000, 0x0B], [0xFE400000, 0x0B],
[0xFE600000, 0x0B], [0xFE800000, 0x0B],
[0xFEA00000, 0x0B], [0xFEC00000, 0x0B],
[0xFEE00000, 0x0B], [0xFF000000, 0x0B],
[0xFF200000, 0x0B], [0xFF400000, 0x0B],
[0xFF600000, 0x0B], [0xFF800000, 0x0B],
[0xFFA00000, 0x0B], [0xFFC00000, 0x0B],
[0xFFE00000, 0x13], [0xFFE02000, 0x13],
[0xFFE04000, 0x13], [0xFFE06000, 0x13],
[0xFFE08000, 0x13], [0xFFE0A000, 0x13],
[0xFFE0C000, 0x13], [0xFFE0E000, 0x13],
[0xFFE10000, 0x13], [0xFFE12000, 0x13],
[0xFFE14000, 0x13], [0xFFE16000, 0x13],
[0xFFE18000, 0x13], [0xFFE1A000, 0x13],
[0xFFE1C000, 0x13], [0xFFE1E000, 0x13],
[0xFFE20000, 0x13], [0xFFE22000, 0x13],
[0xFFE24000, 0x13], [0xFFE26000, 0x13],
[0xFFE28000, 0x13], [0xFFE2A000, 0x13],
[0xFFE2C000, 0x13], [0xFFE2E000, 0x13],
[0xFFE30000, 0x13], [0xFFE32000, 0x13],
[0xFFE34000, 0x13], [0xFFE36000, 0x13],
[0xFFE38000, 0x13], [0xFFE3A000, 0x13],
[0xFFE3C000, 0x13], [0xFFE3E000, 0x13],
[0xFFE40000, 0x13], [0xFFE42000, 0x13],
[0xFFE44000, 0x13], [0xFFE46000, 0x13],
[0xFFE48000, 0x13], [0xFFE4A000, 0x13],
[0xFFE4C000, 0x13], [0xFFE4E000, 0x13],
[0xFFE50000, 0x13], [0xFFE52000, 0x13],
[0xFFE54000, 0x13], [0xFFE56000, 0x13],
[0xFFE58000, 0x13], [0xFFE5A000, 0x13],
[0xFFE5C000, 0x13], [0xFFE5E000, 0x13],
[0xFFE60000, 0x13], [0xFFE62000, 0x13],
[0xFFE64000, 0x13], [0xFFE66000, 0x13],
[0xFFE68000, 0x13], [0xFFE6A000, 0x13],
[0xFFE6C000, 0x13], [0xFFE6E000, 0x13],
[0xFFE70000, 0x13], [0xFFE72000, 0x13],
[0xFFE74000, 0x13], [0xFFE76000, 0x13],
[0xFFE78000, 0x13], [0xFFE7A000, 0x13],
[0xFFE7C000, 0x13], [0xFFE7E000, 0x13],
[0xFFE80000, 0x13], [0xFFE82000, 0x13],
[0xFFE84000, 0x13], [0xFFE86000, 0x13],
[0xFFE88000, 0x13], [0xFFE8A000, 0x13],
[0xFFE8C000, 0x13], [0xFFE8E000, 0x13],
[0xFFE90000, 0x13], [0xFFE92000, 0x13],
[0xFFE94000, 0x13], [0xFFE96000, 0x13],
[0xFFE98000, 0x13], [0xFFE9A000, 0x13],
[0xFFE9C000, 0x13], [0xFFE9E000, 0x13],
[0xFFEA0000, 0x13], [0xFFEA2000, 0x13],
[0xFFEA4000, 0x13], [0xFFEA6000, 0x13],
[0xFFEA8000, 0x13], [0xFFEAA000, 0x13],
[0xFFEAC000, 0x13], [0xFFEAE000, 0x13],
[0xFFEB0000, 0x13], [0xFFEB2000, 0x13],
[0xFFEB4000, 0x13], [0xFFEB6000, 0x13],
[0xFFEB8000, 0x13], [0xFFEBA000, 0x13],
[0xFFEBC000, 0x13], [0xFFEBE000, 0x13],
[0xFFEC0000, 0x13], [0xFFEC2000, 0x13],
[0xFFEC4000, 0x13], [0xFFEC6000, 0x13],
[0xFFEC8000, 0x13], [0xFFECA000, 0x13],
[0xFFECC000, 0x13], [0xFFECE000, 0x13],
[0xFFED0000, 0x13], [0xFFED2000, 0x13],
[0xFFED4000, 0x13], [0xFFED6000, 0x13],
[0xFFED8000, 0x13], [0xFFEDA000, 0x13],
[0xFFEDC000, 0x13], [0xFFEDE000, 0x13],
[0xFFEE0000, 0x13], [0xFFEE2000, 0x13],
[0xFFEE4000, 0x13], [0xFFEE6000, 0x13],
[0xFFEE8000, 0x13], [0xFFEEA000, 0x13],
[0xFFEEC000, 0x13], [0xFFEEE000, 0x13],
[0xFFEF0000, 0x13], [0xFFEF2000, 0x13],
[0xFFEF4000, 0x13], [0xFFEF6000, 0x13],
[0xFFEF8000, 0x13], [0xFFEFA000, 0x13],
[0xFFEFC000, 0x13], [0xFFEFE000, 0x13],
[0xFFF00000, 0x13], [0xFFF02000, 0x13],
[0xFFF04000, 0x13], [0xFFF06000, 0x13],
[0xFFF08000, 0x13], [0xFFF0A000, 0x13],
[0xFFF0C000, 0x13], [0xFFF0E000, 0x13],
[0xFFF10000, 0x13], [0xFFF12000, 0x13],
[0xFFF14000, 0x13], [0xFFF16000, 0x13],
[0xFFF18000, 0x13], [0xFFF1A000, 0x13],
[0xFFF1C000, 0x13], [0xFFF1E000, 0x13],
[0xFFF20000, 0x13], [0xFFF22000, 0x13],
[0xFFF24000, 0x13], [0xFFF26000, 0x13],
[0xFFF28000, 0x13], [0xFFF2A000, 0x13],
[0xFFF2C000, 0x13], [0xFFF2E000, 0x13],
[0xFFF30000, 0x13], [0xFFF32000, 0x13],
[0xFFF34000, 0x13], [0xFFF36000, 0x13],
[0xFFF38000, 0x13], [0xFFF3A000, 0x13],
[0xFFF3C000, 0x13], [0xFFF3E000, 0x13],
[0xFFF40000, 0x13], [0xFFF42000, 0x13],
[0xFFF44000, 0x13], [0xFFF46000, 0x13],
[0xFFF48000, 0x13], [0xFFF4A000, 0x13],
[0xFFF4C000, 0x13], [0xFFF4E000, 0x13],
[0xFFF50000, 0x13], [0xFFF52000, 0x13],
[0xFFF54000, 0x13], [0xFFF56000, 0x13],
[0xFFF58000, 0x13], [0xFFF5A000, 0x13],
[0xFFF5C000, 0x13], [0xFFF5E000, 0x13],
[0xFFF60000, 0x13], [0xFFF62000, 0x13],
[0xFFF64000, 0x13], [0xFFF66000, 0x13],
[0xFFF68000, 0x13], [0xFFF6A000, 0x13],
[0xFFF6C000, 0x13], [0xFFF6E000, 0x13],
[0xFFF70000, 0x13], [0xFFF72000, 0x13],
[0xFFF74000, 0x13], [0xFFF76000, 0x13],
[0xFFF78000, 0x13], [0xFFF7A000, 0x13],
[0xFFF7C000, 0x13], [0xFFF7E000, 0x13],
[0xFFF80000, 0x13], [0xFFF82000, 0x13],
[0xFFF84000, 0x13], [0xFFF86000, 0x13],
[0xFFF88000, 0x13], [0xFFF8A000, 0x13],
[0xFFF8C000, 0x13], [0xFFF8E000, 0x13],
[0xFFF90000, 0x13], [0xFFF92000, 0x13],
[0xFFF94000, 0x13], [0xFFF96000, 0x13],
[0xFFF98000, 0x13], [0xFFF9A000, 0x13],
[0xFFF9C000, 0x13], [0xFFF9E000, 0x13],
[0xFFFA0000, 0x13], [0xFFFA2000, 0x13],
[0xFFFA4000, 0x13], [0xFFFA6000, 0x13],
[0xFFFA8000, 0x13], [0xFFFAA000, 0x13],
[0xFFFAC000, 0x13], [0xFFFAE000, 0x13],
[0xFFFB0000, 0x13], [0xFFFB2000, 0x13],
[0xFFFB4000, 0x13], [0xFFFB6000, 0x13],
[0xFFFB8000, 0x13], [0xFFFBA000, 0x13],
[0xFFFBC000, 0x13], [0xFFFBE000, 0x13],
[0xFFFC0000, 0x13], [0xFFFC2000, 0x13],
[0xFFFC4000, 0x13], [0xFFFC6000, 0x13],
[0xFFFC8000, 0x13], [0xFFFCA000, 0x13],
[0xFFFCC000, 0x13], [0xFFFCE000, 0x13],
[0xFFFD0000, 0x13], [0xFFFD2000, 0x13],
[0xFFFD4000, 0x13], [0xFFFD6000, 0x13],
[0xFFFD8000, 0x13], [0xFFFDA000, 0x13],
[0xFFFDC000, 0x13], [0xFFFDE000, 0x13],
[0xFFFE0000, 0x13], [0xFFFE2000, 0x13],
[0xFFFE4000, 0x13], [0xFFFE6000, 0x13],
[0xFFFE8000, 0x13], [0xFFFEA000, 0x13],
[0xFFFEC000, 0x13], [0xFFFEE000, 0x13],
[0xFFFF0000, 0x13], [0xFFFF2000, 0x13],
[0xFFFF4000, 0x13], [0xFFFF6000, 0x13],
[0xFFFF8000, 0x13], [0xFFFFA000, 0x13],
[0xFFFFC000, 0x13], [0xFFFFE000, 0x13],
[0x00000000, 0x00], [0x00000000, 0x00]
];
/**
* Initialize the Lzpf class.
*
* @returns {undefined}
*/
constructor() {
this.clear();
}
/**
* Sets starting values for the compression algorithm.
*
* @returns {undefined}
*/
clear() {
this.current_length = 0;
this.current_literal = 0;
this.flag = 0xFFFF;
this.working_data = 0;
this.match_index = 0;
this.type_index = 0;
this.checksum = 0;
this.ring_buffer.fill(0x00, 0, 0x2000)
this.flag_table.fill(0xFFFF, 0, 0x1000);
this.encoded_data = [];
}
/**
* Appends a byte to the end of the compressed byte array. Re-allocates as needed
*
* @param byte {Number} char code of the byte to be added.
*
* @returns {undefined}
*/
AddByte(byte) {
this.encoded_data.push(byte);
}
/**
* Encodes a literal onto the compressed byte array.
*
* @param code_length {Number} bit length of the code
* @param code {Number} code to be encoded
*
* @returns {undefined}
*/
EncodeLiteral(code_length, code) {
// Using >>> to stick with unsigned integers without making a mess with casting.
this.current_literal |= code >>> (this.current_length & 0x1F);
this.current_length += code_length;
while (this.current_length > 7) {
this.AddByte((this.current_literal >>> 0x18) & 0xFF);
this.current_length -= 8;
this.current_literal = (this.current_literal << 8) & 0xFFFFFFFF;
}
}
/**
* Starts a compression stream
*
* @returns {undefined} Lzpf compression data
*/
Begin() {
this.clear();
}
/**
* Encode a block of data. Used for streamed chunks.
*
* @param unencoded_data {Buffer} data to encode
* @param compress_data {Boolean} compress data
*
* @returns {Buffer} Lzpf encoded data
*/
EncodeBlock(unencoded_data, compress_data) {
this.encoded_data = [];
var uncompressed_len = unencoded_data.byteLength;
var i = 0;
var flags_index = 0;
while (i < uncompressed_len) {
var code_length = -1;
var code = -1;
var byte = unencoded_data.readUInt8(i);
this.ring_buffer[i & 0x1FFF] = byte;
if (this.match_index > 0) {
if (byte != this.ring_buffer[this.flag] || this.match_index > 0x0127) {
code_length = this.matchEncode[this.match_index][1];
code = this.matchEncode[this.match_index][0];
this.match_index = 0;
this.type_index = 3;
} else {
this.match_index = (this.match_index + 1) & 0x1FFF;
this.flag = (this.flag + 1) & 0x1FFF;
this.checksum = (this.checksum + byte) & 0xFFFF;
this.working_data = ((this.working_data * 0x0100) + byte) & 0xFFFFFFFF;
i++;
}
} else {
this.flag = 0xFFFF;
if (i >= 3) {
flags_index = (this.working_data >>> 0x0B ^ this.working_data) & 0x0FFF;
this.flag = this.flag_table[flags_index];
this.flag_table[flags_index] = i & 0x1FFF;
} else {
this.type_index++;
}
if (this.flag == 0xFFFF) {
code_length = this.nomatchEncode[byte][1];
code = this.nomatchEncode[byte][0] << 0x10;
} else if (byte == this.ring_buffer[this.flag] && compress_data) {
this.match_index = 1;
this.flag = (this.flag + 1) & 0x1FFF;
this.type_index = 4;
} else {
code_length = this.nomatchEncode[byte][1] + 1;
code = this.nomatchEncode[byte][0] << 0x0F;
}
this.checksum = (this.checksum + byte) & 0xFFFF;
this.working_data = ((this.working_data * 0x0100) + byte) & 0xFFFFFFFF;
i++;
}
if (code_length > 0) {
this.EncodeLiteral(code_length, code);
}
}
return Buffer.from(this.encoded_data);
}
/**
* Ends a compression stream.
*
* @param type_index {Number} the end type used to finalize
*
* @returns {Buffer} Lzpf compression data
*/
Finish() {
var code_length = -1;
var code = -1;
if (this.type_index == 2) {
this.EncodeLiteral(0x10, 0x00990000);
} else if (this.type_index >= 3) {
if (this.type_index == 4) {
code_length = this.matchEncode[this.match_index][1];
code = this.matchEncode[this.match_index][0];
this.EncodeLiteral(code_length, code);
}
var flags_index = (this.working_data >>> 0x0B ^ this.working_data) & 0x0FFF;
var flag = this.flag_table[flags_index];
if (flag == 0xFFFF) {
this.EncodeLiteral(0x10, 0x00990000);
} else {
this.EncodeLiteral(0x11, 0x004c8000);
}
}
// Below is just metadata. The compressed block is complete.
// Encode checksum
this.EncodeLiteral(0x08, (this.checksum << 0x10) & 0xFFFFFFFF);
this.EncodeLiteral(0x08, (this.checksum << 0x18) & 0xFFFFFFFF);
// End
this.AddByte((this.current_literal >>> 0x18) & 0xFF);
this.AddByte(0x20);
}
/**
* Converts the data to a Javascript Buffer object
*
* @param data {String|Buffer|CryptoJS.lib.WordArray} Data to convert
*
* @returns {Buffer} Javascript Buffer object
*/
ConvertToBuffer(data) {
if (data.words) {
var WTVSec = require("./WTVSec.js");
wtvsec = new WTVSec(1);
data = wtvsec.wordArrayToBuffer(data);
WTVSec, wtvsec = null;
} else if (!data.byteLength) {
// otherwise if its not already a Buffer, convert it to one
data = new Buffer.from(data);
}
return data;
}
/**
* Compress data using WebTV's Lzpf compression algorithm and adds the footer to the end.
*
* @param uncompressed_data {String|Buffer|CryptoJS.lib.WordArray} data to compress
*
* @returns {Buffer} Lzpf compression data
*/
Compress(uncompressed_data) {
uncompressed_data = this.ConvertToBuffer(uncompressed_data);
this.Begin();
this.EncodeBlock(uncompressed_data, true);
this.Finish();
return Buffer.from(this.encoded_data);
}
}
module.exports = WTVLzpf;
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