Hi, Jonathan Tan wrote: > Suppose you have missing blob AB12 and CD34 that you now need, so > fetch-blob is invoked. It sends the literals AB12 and CD34 to a new > server endpoint and obtains a packfile, which it then pipes through "git > index-pack". The issue is that "git index-pack" wants to try to access > AB12 and CD34 in the local repo in order to do a SHA-1 collision check, > and therefore fetch-blob is invoked once again, creating infinite > recursion. [...] > 2. Add support for an environment variable to Git that suppresses access > to the missing blob manifest, in effect, suppressing invocation of the > hook. This allows anyone (the person configuring Git or the hook writer) > to suppress this access, although they might need in-depth knowledge to > know whether the hook is meant to be run with such access suppressed or > required. Small tweak: what if Git itself sets that environment variable when invoking the hook? A fetch-blob hook author can then explicitly unset the environment variable to request recursion if they need it. I should credit Shawn Pearce for saying this a little more clearly offline a moment ago. Thanks, Jonathan
