Retrieved from https://microsoft.visualstudio.com os.2020 OS official/rs_wdx_dxp_windev 063b86ac10af16cade5c0754adcbf27e7e9ae266
Related work items: MSFT-34534216, MSFT-36986009, MSFT-36986203
This commit renames `Base64::s_Decode` into `Base64::Decode` and improves its
average performance on short strings of less than 200 characters by 4.5x.
This is achieved by implementing a classic base64 decoder that reads 4
characters at a time and produces 3 output bytes. Furthermore a small
128 byte lookup table is used to quickly map characters to values.
## PR Checklist
* [x] I work here
* [x] Tests added/passed
## Validation Steps Performed
* Run WSL in Windows Terminal
* Run `printf "\033]52;c;aHR0cHM6Ly9naXRodWIuY29tL21pY3Jvc29mdC90ZXJtaW5hbC9wdWxsLzExNDY3\a"`
* Clipboard contains `https://github.com/microsoft/terminal/pull/11467` ✔️
This commit adds a missing conversion utf8 to utf16 in decoding base64
for handling multibyte text in copying via OSC 52.
## Validation Steps Performed
* automatically
* Tests w/ multibyte characters
* manually
* case1
* Executed `printf "\x1b]52;;%s\x1b\\" "$(printf '👍👍🏻👍🏼👍🏽👍🏾👍🏿' | base64)"`
* Verified `👍👍🏻👍🏼👍🏽👍🏾👍🏿` in my clipboard
* case2
* Copied `👍👍🏻👍🏼👍🏽👍🏾👍🏿` by tmux 2.6 default copy function (OSC 52)
* Verified `👍👍🏻👍🏼👍🏽👍🏾👍🏿` in my clipboard
Closes#7819
With this commit, terminal will be able to copy text to the system
clipboard by using OSC 52 MANIPULATE SELECTION DAATA.
We chose not to implement the clipboard querying functionality offered
by OSC 52, as sending the clipboard text to an application without the
user's knowledge or consent is an immense security hole.
We do not currently support the clipboard specifier Pc to specify which
clipboard buffer should be filled
# Base64 encoded `foo`
$ echo -en "\e]52;;Zm9v\a"
# Multiple lines
# Base64 encoded `foo\r\nbar`
$ echo -en "\e]52;;Zm9vDQpiYXI=\a"
Closes#2946.
