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authorDanijel Andjelkovic <adanijel99@gmail.com>2022-03-01 20:21:29 +0000
committerDanijel Andjelkovic <adanijel99@gmail.com>2022-03-01 20:21:29 +0000
commit61cb1570a3410c85a4489b97c172e3a50715f36c (patch)
tree8fe4a5b77ea54bba80abc817ce2c9ef0e79e7e66 /sandbox/testAppNevena/Front/node_modules/tar/lib/large-numbers.js
parent21a53d349788c99d2007cba91a923db982353b31 (diff)
parenta9ee9e0a500a4a15bd0b5dcaf041f827228ed309 (diff)
Merge branch 'researchML' into 'dev'
Research ml See merge request igrannonica/neuronstellar!6
Diffstat (limited to 'sandbox/testAppNevena/Front/node_modules/tar/lib/large-numbers.js')
-rw-r--r--sandbox/testAppNevena/Front/node_modules/tar/lib/large-numbers.js99
1 files changed, 99 insertions, 0 deletions
diff --git a/sandbox/testAppNevena/Front/node_modules/tar/lib/large-numbers.js b/sandbox/testAppNevena/Front/node_modules/tar/lib/large-numbers.js
new file mode 100644
index 00000000..dd6f690b
--- /dev/null
+++ b/sandbox/testAppNevena/Front/node_modules/tar/lib/large-numbers.js
@@ -0,0 +1,99 @@
+'use strict'
+// Tar can encode large and negative numbers using a leading byte of
+// 0xff for negative, and 0x80 for positive.
+
+const encode = (num, buf) => {
+ if (!Number.isSafeInteger(num))
+ // The number is so large that javascript cannot represent it with integer
+ // precision.
+ throw Error('cannot encode number outside of javascript safe integer range')
+ else if (num < 0)
+ encodeNegative(num, buf)
+ else
+ encodePositive(num, buf)
+ return buf
+}
+
+const encodePositive = (num, buf) => {
+ buf[0] = 0x80
+
+ for (var i = buf.length; i > 1; i--) {
+ buf[i - 1] = num & 0xff
+ num = Math.floor(num / 0x100)
+ }
+}
+
+const encodeNegative = (num, buf) => {
+ buf[0] = 0xff
+ var flipped = false
+ num = num * -1
+ for (var i = buf.length; i > 1; i--) {
+ var byte = num & 0xff
+ num = Math.floor(num / 0x100)
+ if (flipped)
+ buf[i - 1] = onesComp(byte)
+ else if (byte === 0)
+ buf[i - 1] = 0
+ else {
+ flipped = true
+ buf[i - 1] = twosComp(byte)
+ }
+ }
+}
+
+const parse = (buf) => {
+ const pre = buf[0]
+ const value = pre === 0x80 ? pos(buf.slice(1, buf.length))
+ : pre === 0xff ? twos(buf)
+ : null
+ if (value === null)
+ throw Error('invalid base256 encoding')
+
+ if (!Number.isSafeInteger(value))
+ // The number is so large that javascript cannot represent it with integer
+ // precision.
+ throw Error('parsed number outside of javascript safe integer range')
+
+ return value
+}
+
+const twos = (buf) => {
+ var len = buf.length
+ var sum = 0
+ var flipped = false
+ for (var i = len - 1; i > -1; i--) {
+ var byte = buf[i]
+ var f
+ if (flipped)
+ f = onesComp(byte)
+ else if (byte === 0)
+ f = byte
+ else {
+ flipped = true
+ f = twosComp(byte)
+ }
+ if (f !== 0)
+ sum -= f * Math.pow(256, len - i - 1)
+ }
+ return sum
+}
+
+const pos = (buf) => {
+ var len = buf.length
+ var sum = 0
+ for (var i = len - 1; i > -1; i--) {
+ var byte = buf[i]
+ if (byte !== 0)
+ sum += byte * Math.pow(256, len - i - 1)
+ }
+ return sum
+}
+
+const onesComp = byte => (0xff ^ byte) & 0xff
+
+const twosComp = byte => ((0xff ^ byte) + 1) & 0xff
+
+module.exports = {
+ encode,
+ parse,
+}