major bug fixes, append number yet to be unit tested

This commit is contained in:
ferricles 2022-06-24 00:15:06 -07:00
parent bbede794b9
commit 95cd93ad4d

View file

@ -159,46 +159,40 @@ Base64 = (function () {
/** Constructs an arbitrary-length bit vector.
* @class
* @param {String | Number} data
* @param {Number} length - a set length for the data. Must be in the range [0, 32] if data is a Number.
* @param {String | Number} data - The data to append.
* @param {Number} length - A set length for the data. Ignored if data is a string.
*
* The structure of the Uint32Array should be [[last, ..., first], ..., [last, ..., first], [empty space, last, ..., first]]
*/
constructor(data, length) {
let bit_vec = [];
if (typeof data === "string") {
let int = 0;
let bv_idx = 0;
length = data.length * 6;
for (let i = 0; i < data.length; i++) {
let char = Base64.toInt(data[i]);
let pre_pos = bv_idx % 32;
int |= (char << bv_idx);
bv_idx += 6;
let post_pos = bv_idx % 32;
if (post_pos < pre_pos) { //we have to have filled up the integer
bit_vec.push(int);
int = (char >>> (6 - post_pos));
}
if (i == data.length - 1 && post_pos != 0) {
bit_vec.push(int);
}
}
} else if (typeof data === "number") {
if (typeof length === "undefined")
if (length < 0) {
throw new RangeError("BitVector must have nonnegative length.");
}
if (typeof data === "string") {
//string in B64
let curr = 0;
let total_bits = 0;
let i = 0;
//override length passed in if it's > length of string naturally to save space
length = Math.min(length, data.length * 6);
while (i < data.length && total_bits < length) {
let int = Base64.toInt(data[i])
//total_bits implicitly % 32 here
curr |= (int << total_bits);
if (total_bits % 32 > 25) {
//push and roll over uncaught bits
bit_vec.push(curr);
curr = (int >>> (32 - (total_bits % 32)));
}
i++;
total_bits += 6;
}
//need to push remaining bits if not pushed yet
if (total_bits % 32 != 0) {
bit_vec.push(curr);
}
} else if (typeof data === "number") {
//convert to int just in case
data = Math.round(data);
@ -217,12 +211,12 @@ Base64 = (function () {
/** Return value of bit at index idx.
*
* @param {Number} idx - the index to read
* @param {Number} idx - The index to read
*
* @returns the bit value at position idx
* @returns The bit value at position idx
*/
read_bit(idx) {
if (idx < 0 || idx > this.length) {
if (idx < 0 || idx >= this.length) {
throw new RangeError("Cannot read bit outside the range of the BitVector.");
}
return ((this.bits[Math.floor(idx / 32)] & (1 << (idx % 32))) == 0 ? 0 : 1);
@ -230,10 +224,10 @@ Base64 = (function () {
/** Returns an integer value (if possible) made from the range of bits [start, end). Undefined behavior if the range to read is too big.
*
* @param {Number} start - the index to start slicing from. Inclusive
* @param {Number} end - the index to end slicing at. Exclusive
* @param {Number} start - The index to start slicing from. Inclusive.
* @param {Number} end - The index to end slicing at. Exclusive.
*
* @returns an integer representation of the sliced bits.
* @returns An integer representation of the sliced bits.
*/
slice(start, end) {
//TO NOTE: JS shifting is ALWAYS in mod 32. a << b will do a << (b mod 32) implicitly.
@ -269,7 +263,7 @@ Base64 = (function () {
/** Assign bit at index idx to 1.
*
* @param {Number} idx - the index to set
* @param {Number} idx - The index to set.
*/
set_bit(idx) {
if (idx < 0 || idx > this.length) {
@ -280,7 +274,7 @@ Base64 = (function () {
/** Assign bit at index idx to 0.
*
* @param {Number} idx - the index to clear
* @param {Number} idx - The index to clear.
*/
clear_bit(idx) {
if (idx < 0 || idx > this.length) {
@ -291,7 +285,7 @@ Base64 = (function () {
/** Creates a string version of the bit vector in B64. Does not keep the order of elements a sensible human readable format.
*
* @returns a b64 string representation of the BitVector
* @returns A b64 string representation of the BitVector.
*/
toB64() {
if (this.length == 0) {
@ -309,7 +303,7 @@ Base64 = (function () {
/** Returns a BitVector in bitstring format. Probably only useful for dev debugging.
*
* @returns a bit string representation of the BitVector. Goes from higher-indexed bits to lower-indexed bits.
* @returns A bit string representation of the BitVector. Goes from higher-indexed bits to lower-indexed bits. (n ... 0)
*/
toString() {
let ret_str = "";
@ -319,10 +313,22 @@ Base64 = (function () {
return ret_str;
}
/** Returns a BitVector in bitstring format. Probably only useful for dev debugging.
*
* @returns A bit string representation of the BitVector. Goes from lower-indexed bits to higher-indexed bits. (0 ... n)
*/
toStringR() {
let ret_str = "";
for (let i = 0; i < this.length; i++) {
ret_str += (this.read_bit(i) == 0 ? "0": "1");
}
return ret_str;
}
/** Appends data to the BitVector.
*
* @param {Number | String} data
* @param {Number} length - the length, in bits, of the new data
* @param {Number | String} data - The data to append.
* @param {Number} length - The length, in bits, of the new data. This is ignored if data is a string.
*/
append(data, length) {
if (length < 0) {
@ -334,51 +340,47 @@ Base64 = (function () {
bit_vec.push(uint);
}
if (typeof data === "string") {
//string in B64
let curr = bit_vec[Math.floor(this.length / 32)];
let total_bits = this.length;
let i = 0;
//override length passed in if it's > length of string naturally to save space
length = Math.min(length, data.length * 6);
while (i < data.length && total_bits < this.length + length) {
let int = Base64.toInt(data[i])
//total_bits implicitly % 32 here
curr |= (int << total_bits);
if (total_bits % 32 > 25) {
//push and roll over uncaught bits
if (bit_vec.length == (Math.floor(this.length / 32) + 1)) {
bit_vec[Math.floor(this.length / 32)] = curr;
let int = bit_vec[bit_vec.length - 1];
let bv_idx = this.length;
length = data.length * 6;
let updated_curr = false;
for (let i = 0; i < data.length; i++) {
let char = Base64.toInt(data[i]);
let pre_pos = bv_idx % 32;
int |= (char << bv_idx);
bv_idx += 6;
let post_pos = bv_idx % 32;
if (post_pos < pre_pos) { //we have to have filled up the integer
if (bit_vec.length == this.bits.length && !updated_curr) {
bit_vec[bit_vec.length - 1] = int;
updated_curr = true;
} else {
bit_vec.push(curr);
bit_vec.push(int);
}
curr = (int >>> (32 - (total_bits % 32)));
int = (char >>> (6 - post_pos));
}
i++;
total_bits += 6;
if (i == data.length - 1) {
if (bit_vec.length == this.bits.length && !updated_curr) {
bit_vec[bit_vec.length - 1] = int;
} else if (post_pos != 0) {
bit_vec.push(int);
}
}
//need to push remaining bits if not pushed yet
if (total_bits % 32 != 0) {
bit_vec.push(curr);
}
} else if (typeof data === "number") {
//convert to int just in case
let int = Math.round(data);
//range of numbers that "could" fit in a uint32 -> [0, 2^32) U (-2^31, 2^31)
if (data > 2**32 - 1 || data < -(2 ** 31 - 1)) {
//range of numbers that "could" fit in a uint32 -> [0, 2^32) U [-2^31, 2^31)
if (data > 2**32 - 1 || data < -(2 ** 31)) {
throw new RangeError("Numerical data has to fit within a 32-bit integer range to instantiate a BitVector.");
}
//could be split between multiple new ints
//reminder that shifts implicitly mod 32
bit_vec[Math.floor(this.length / 32)] |= ((int & ~((~0) << length)) << (this.length));
if (Math.floor((this.length + length) / 32) > Math.floor(this.length / 32)) {
bit_vec.push(int >>> (this.length));
bit_vec[bit_vec.length - 1] |= ((int & ~((~0) << length)) << (this.length));
if (((this.length + length) % 32 < ((this.length - 1) % 32) + 1) || ((this.length + length) % 32 != 0)) {
bit_vec.push(int >>> (32 - this.length));
}
} else {
throw new TypeError("BitVector must be appended with a Number or a B64 String");