32 lines
817 B
Bash
Executable File
32 lines
817 B
Bash
Executable File
#!/usr/bin/env bash
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b64_encode() {
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local idx=0 numerics table_idxs table_idx encoded
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local table=( {A..Z} {a..z} {0..9} + / )
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for (( ; idx < ${#1}; idx+=3 )); do
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read -ra numerics < <(
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printf '%d %d %d\n' "'${1:idx:1}" "'${1:idx+1:1}" "'${1:idx+2:1}"
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)
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(( table_idxs[0] = numerics[0] >> 2 ))
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(( table_idxs[1] = (( (numerics[0] & 0x03) << 6) | (numerics[1] & 0xF0) >> 2) >> 2 ))
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(( table_idxs[2] = (( (numerics[1] & 0x0F) << 4) | (numerics[2] & 0xC0) >> 4) >> 2 ))
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(( table_idxs[3] = numerics[2] & 0x3F ))
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for table_idx in "${table_idxs[@]}"; do
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encoded+=${table[$table_idx]}
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done
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done
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if (( ${#1} % 3 == 1 )); then
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encoded=${encoded::-2}==
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elif (( ${#1} % 3 == 2 )); then
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encoded=${encoded::-1}=
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fi
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printf '%s\n' "$encoded"
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}
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b64_encode "$1"
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