Use absolute positioning after OSC sequences#74
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seh wants to merge 1 commit intocharmbracelet:mainfrom
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Use absolute positioning after OSC sequences#74seh wants to merge 1 commit intocharmbracelet:mainfrom
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Sending OSC (Operating System Command) sequences to terminals can induce inconsistency in the expected cursor position. When we write an OSC sequence to the terminal, it may move the cursor unpredictably, leaving "ultraviolet"'s cached cursor position unknowingly incorrect. To defend against this vulnerability, detect OSC sequences in the TerminalRenderer type's "Write" and "WriteString" methods, and, upon detecting such sequences, force the next cursor movement to use absolute positioning (CUP) rather than relative movements. Doing so ensures that we restore proper cursor synchronization after having pushed these OSC sequences through to the terminal. The material change in behavior only applies when the "tRelativeCursor" flag is unset (typically in the so-called alternate screen buffer mode), where absolute cursor positioning is available but the consequent inconsistency can cause visible rendering artifacts (such as stale lines not being overwritten as intended).
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Sending OSC (Operating System Command) sequences to terminals can induce inconsistency in the expected cursor position. When we write an OSC sequence to the terminal, it may move the cursor unpredictably, leaving ultraviolet's cached cursor position unknowingly incorrect.
To defend against this vulnerability, detect OSC sequences in the
TerminalRenderertype'sWriteandWriteStringmethods, and, upon detecting such sequences, force the next cursor movement to use absolute positioning (CUP) rather than relative movements. Doing so ensures that we restore proper cursor synchronization after having pushed these OSC sequences through to the terminal.The material change in behavior only applies when the
tRelativeCursorflag is unset (typically in the so-called alternate screen buffer mode), where absolute cursor positioning is available but the consequent inconsistency can cause visible rendering artifacts (such as stale lines not being overwritten as intended).CONTRIBUTING.md.