Investigate mmap behavior with changing file lengths
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- Dominant language
- C++
- Stars
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- Forks
- 662
- Avg merge
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- Merged PRs (30d)
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Description
Right now we assume that the size of an mmapped file never changes (except possibly accompanies by an mremap). However I think it's possible to mmap a file and then use ftruncate to change its length. This would require special handling in rr.
Contributor guide
First steps
- Read the whole issue, then the project's contributing guide.
- Comment on the issue to say you are picking it up — it saves two people doing the same work.
- Fork the repository and make your change on a branch.
- Open a pull request that references the issue number.
Research direction
No source file, test, or entry point is named. Start by reproducing an mmap followed by ftruncate on Linux and compare rr's behavior during recording and replay. Done means the behavior is understood and any required special handling is identified and validated.
Written by the indexing model from the issue text.
Assessment
- Tech stack
- cpp, linux
- Domain
- devtools, operating-systems
- Issue type
- Bug
- Difficulty
- 5/5
- Estimated time
- Over a week
- Activity status
- Stale
- Clarity
- Needs clarification
- Newbie friendliness
- 25/100