crc32.njs
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#!/usr/bin/env node
/* crc32.js (C) 2014-present SheetJS -- http://sheetjs.com */
/* eslint-env node */
/* vim: set ts=2 ft=javascript: */
/*jshint node:true */
var X/*:CRC32Module*/;
try { X = require('../'); } catch(e) { X = require('crc-32'); }
function help()/*:number*/ {
[
"usage: crc32 [options] [filename]",
"",
"Options:",
" -h, --help output usage information",
" -V, --version output the version number",
" -S, --seed=<n> use integer seed as starting value (rolling CRC)",
" -H, --hex-seed=<h> use hex seed as starting value (rolling CRC)",
" -d, --signed print result with format `%d` (default)",
" -u, --unsigned print result with format `%u`",
" -x, --hex print result with format `%0.8x`",
" -X, --HEX print result with format `%0.8X`",
" -c, --crc32c use CRC32C (Castagnoli)",
" -F, --format=<s> use specified printf format",
"",
"Set filename = '-' or pipe data into crc32 to read from stdin",
"Default output mode is signed (-d)",
""
].forEach(function(l) { console.log(l); });
return 0;
}
function version()/*:number*/ { console.log(X.version); return 0; }
var fs = require('fs');
try { require('exit-on-epipe'); } catch(e) {}
function die(msg/*:string*/, ec/*:?number*/)/*:void*/ { console.error(msg); process.exit(ec || 0); }
var args/*:Array<string>*/ = process.argv.slice(2);
var filename/*:string*/ = "";
var fmt/*:string*/ = "";
var seed = 0, r = 10;
for(var i = 0; i < args.length; ++i) {
var arg = args[i];
if(arg.charCodeAt(0) != 45) { if(filename === "") filename = arg; continue; }
var m = arg.indexOf("=") == -1 ? arg : arg.substr(0, arg.indexOf("="));
switch(m) {
case "-": filename = "-"; break;
case "--help": case "-h": process.exit(help()); break;
case "--version": case "-V": process.exit(version()); break;
case "--crc32c": case "-c": try { X = require('../crc32c'); } catch(e) { X = require('crc-32/crc32c'); } break;
case "--signed": case "-d": fmt = "%d"; break;
case "--unsigned": case "-u": fmt = "%u"; break;
case "--hex": case "-x": fmt = "%0.8x"; break;
case "--HEX": case "-X": fmt = "%0.8X"; break;
case "--format": case "-F":
try {
require("printj");
fmt = ((m!=arg) ? arg.substr(m.length+1) : args[++i])||"";
} catch(e) {
console.error("The `crc-32` module removed the `printj` dependency for formatting");
console.error("Use the `crc32-cli` module instead:");
console.error(" $ npx crc32-cli [options] [filename]");
} break;
case "--hex-seed": case "-H": r = 16;
/* falls through */
case "--seed": case "-S":
seed=parseInt((m!=arg) ? arg.substr(m.length+1) : args[++i], r)||0; break;
default: die("crc32: unrecognized option `" + arg + "'", 22);
}
}
if(!process.stdin.isTTY) filename = filename || "-";
if(filename.length===0) die("crc32: must specify a filename ('-' for stdin)",1);
var crc32 = seed;
// $FlowIgnore -- Writable is callable but type sig disagrees
var writable = require('stream').Writable();
writable._write = function(chunk, e, cb) { crc32 = X.buf(chunk, crc32); cb(); };
writable._writev = function(chunks, cb) {
chunks.forEach(function(c) { crc32 = X.buf(c.chunk, crc32);});
cb();
};
writable.on('finish', function() {
if(fmt === "") console.log(crc32);
else try { console.log(require("printj").sprintf(fmt, crc32)); } catch(e) {
switch(fmt) {
case "%d": console.log(crc32); break;
case "%u": console.log(crc32 >>> 0); break;
case "%0.8x": console.log((crc32 >>> 0).toString(16).padStart(8, "0").toLowerCase()); break;
case "%0.8X": console.log((crc32 >>> 0).toString(16).padStart(8, "0").toUpperCase()); break;
}
}
});
if(filename === "-") process.stdin.pipe(writable);
else if(fs.existsSync(filename)) fs.createReadStream(filename).pipe(writable);
else die("crc32: " + filename + ": No such file or directory", 2);