chore: Initial commit

Author: hyperupcall

.gitignore

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+.basalt/

README.md

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+# bash-algo
+
+Common algorithms implemented in pure Bash
+
+All algorithms use _only_ builtins and create _no subshells_
+
+## Algorithms
+
+- [x] base64 encode
+- [ ] base64 decode
+- [ ] md5
+- [ ] sha1
+- [ ] sha256

basalt.toml

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+[package]
+name = 'bash-algo'
+slug = 'balgo'
+version = ''
+authors = ['Edwin Kofler <[email protected]>']
+description = 'Common algorithms implemented in pure Bash'
+
+[run]
+dependencies = ['https://github.com/hyperupcall/[email protected]']
+sourceDirs = ['pkg/lib/public']
+builtinDirs = []
+binDirs = []
+completionDirs = []
+manDirs = []
+
+[run.shellEnvironment]
+
+[run.setOptions]
+
+[run.shoptOptions]

pkg/lib/public/bash-algo.sh

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+# shellcheck shell=bash
+
+algo.base64encode() {
+	unset REPLY; REPLY=
+	local input="$1"
+
+	local char_str="ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"
+	local has_{second,third}_byte=
+	local {first,second,third}_{byte,char}=
+	for ((i=0; i<${#input}; i=i+3)); do
+		has_second_byte=
+		has_third_byte=
+
+		# These branches execute if the string's length isn't divisible by 3. i.e., it
+		# is divisible by 2 or only 1 (has lengths of 4, or 5). The i+1 is skipped because
+		# it will always be true due to the condition in the for loop
+		printf -v first_byte '%d' "'${input:$i:1}"
+
+		# TODO: can simplify if empty string results in 0
+		if ((i+2 > ${#input})); then
+			second_byte=$((2#00000000))
+		else
+			has_second_byte=yes
+			printf -v second_byte '%d' "'${input:$i+1:1}"
+		fi
+
+		if ((i+3 > ${#input})); then
+			third_byte=$((2#00000000))
+		else
+			has_third_byte=yes
+			printf -v third_byte '%d' "'${input:$i+2:1}"
+		fi
+
+		new_first_bits=$(( (first_byte >> 2) & 2#00111111 ))
+		new_second_bits=$(( ((first_byte & 2#00000011) << 4) | ((second_byte & 2#11110000) >> 4 & 2#00001111) ))
+		new_third_bits=$(( (second_byte & 2#00001111) << 2 | third_byte >> 6 & 2#00000011 ))
+		new_fourth_bits=$(( third_byte & 2#00111111 ))
+
+		first_char="${char_str:$new_first_bits:1}"
+		second_char="${char_str:$new_second_bits:1}"
+
+		if [ "$has_second_byte" = yes ]; then
+			third_char="${char_str:$new_third_bits:1}"
+		else
+			third_char='='
+		fi
+		if [ "$has_third_byte" = yes ]; then
+			fourth_char="${char_str:$new_fourth_bits:1}"
+		else
+			fourth_char='='
+		fi
+
+		REPLY+="$first_char$second_char$third_char$fourth_char"
+	done
+}

tests/all.bats

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+#!/usr/bin/env bash
+
+load './util/init.sh'
+
+@test "base64encode" {
+	algo.base64encode "paraguay-uruguay"
+	assert [ "$REPLY" = 'cGFyYWd1YXktdXJ1Z3VheQ==' ]
+
+	test_util.base64encode 'A'
+	test_util.base64encode 'AB'
+	test_util.base64encode 'ABC'
+	test_util.base64encode 'ABCD'
+	test_util.base64encode 'WOOF'
+	test_util.base64encode 'kafka38quebec'
+	test_util.base64encode 'EcHo##8(0}}'
+}

tests/util/init.sh

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+# shellcheck shell=bash
+
+eval "$(basalt-package-init)"
+basalt.package-init
+basalt.package-load
+basalt.load 'github.com/hyperupcall/bats-common-utils' 'load.bash'
+
+load './util/test_util.sh'
+
+setup() {
+	cd "$BATS_TEST_TMPDIR"
+}
+
+teardown() {
+	cd "$BATS_SUITE_TMPDIR"
+}

tests/util/test_util.sh

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+# shellcheck shell=bash
+
+test_util.base64encode() {
+	algo.base64encode "$1"
+	assert [ "$REPLY" = "$(printf '%s' "$1" | base64)" ]
+}