RFR: 8281384: Random chars on paste from Windows clipboard [v4]

[Michael Strauß]

On Wed, 26 Feb 2025 18:28:28 GMT, Oliver Schmidtmer <oschmidtmer at openjdk.org> wrote:

>> Windows programs may reuse a clipboard buffer that is larger than the new content. In this case de NUL terminator is not at the end of the buffer, but within it. 
>> The current implementation copys the whole buffer into a text field, including the NUL terminator and the remaining chars.
>> 
>> The JIRA ticket contains a JNA based sample program, which prefills the buffer for demonstrating this issue.
>> If this should be added as a unit test, I'm open for advice how to do that.
>
> Oliver Schmidtmer has updated the pull request incrementally with one additional commit since the last revision:
> 
>   cleanup

modules/javafx.graphics/src/main/native-glass/win/GlassClipboard.cpp line 406:

> 404:                 cdata = 0;
> 405:             }
> 406:         } else if(CF_TEXT == cf || CF_UNICODETEXT == cf){

Instead of doing that, consider always requesting `CF_UNICODETEXT` from the clipboard. Windows will then convert both `CF_TEXT` and `CF_OEMTEXT` to unicode (see [Synthesized Clipboard Formats](https://learn.microsoft.com/en-us/windows/win32/dataxchg/clipboard-formats)).

modules/javafx.graphics/src/main/native-glass/win/GlassClipboard.cpp line 409:

> 407:             for(int i = 0; i < cdata - 1; i+=2){
> 408:                 jbyte *pos = me.getMem() + offset + i;
> 409:                 if(*(pos) == 0 && *(pos + 1) == 0){

1. `offset` is always 0 here.
2. Minor: add spacing around operators and after keywords (`for`, `if`).

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PR Review Comment: https://git.openjdk.org/jfx/pull/1724#discussion_r1972777624
PR Review Comment: https://git.openjdk.org/jfx/pull/1724#discussion_r1972778132