Fix segfault when switching to full terminal mode #90
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When the terminal is resized (e.g., when switching from grid mode to full mode with different font scales), the VT stream handler contained stale pointers to the terminal's internal buffer structures. After terminal.resize() reallocates buffers, the ReadonlyHandler in the stream had invalid pointers, causing a segfault when processOutput() attempted to read from the stream. Solution: Recreate the VT stream after each terminal resize to ensure the stream handler has fresh pointers to the resized terminal's internal state.
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Pull request overview
This PR fixes a segmentation fault that occurred when switching to full terminal mode by addressing stale pointers in the VT stream handler after terminal resizing.
Changes:
- Added stream recreation logic after terminal resize to maintain valid pointers
- Refactored resize loop to use early continues for improved control flow
- Added
vt_streamimport to support stream recreation
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Summary
Fixes a segmentation fault that occurred when entering full terminal mode (or any mode transition that triggers a terminal resize with font scale changes).
Root Cause
The VT stream handler (
vt_stream::Handler) contains aReadonlyHandlerthat holds pointers to the terminal's internal buffer structures. When the terminal is resized:applyTerminalResizeterminal.resize()reallocates internal buffers, invalidating pointers in theReadonlyHandlerprocessOutput()attempts to read from the stream with stale pointers → segfault at0x164545398Solution
Recreate the VT stream after each terminal resize to ensure the stream handler has fresh pointers to the resized terminal's internal state.
Changes
vt_streamimport tomain.zigapplyTerminalResize()to deinit and recreate the stream after terminal resizeTest Plan
zig build)zig build test)