git/cache.h, branch v2.29.2

builtin/clone: avoid failure with GIT_DEFAULT_HASH

2020-09-22T16:22:32Z

If a user is cloning a SHA-1 repository with GIT_DEFAULT_HASH set to "sha256", then we can end up with a repository where the repository format version is 0 but the extensions.objectformat key is set to "sha256". This is both wrong (the user has a SHA-1 repository) and nonfunctional (because the extension cannot be used in a v0 repository). This happens because in a clone, we initially set up the repository, and then change its algorithm based on what the remote side tells us it's using. We've initially set up the repository as SHA-256 in this case, and then later on reset the repository version without clearing the extension. We could just always set the extension in this case, but that would mean that our SHA-1 repositories weren't compatible with older Git versions, even though there's no reason why they shouldn't be. And we also don't want to initialize the repository as SHA-1 initially, since that means if we're cloning an empty repository, we'll have failed to honor the GIT_DEFAULT_HASH variable and will end up with a SHA-1 repository, not a SHA-256 repository. Neither of those are appealing, so let's tell the repository initialization code if we're doing a reinit like this, and if so, to clear the extension if we're using SHA-1. This makes sure we produce a valid and functional repository and doesn't break any of our other use cases. Reported-by: Matheus Tavares Signed-off-by: brian m. carlson Signed-off-by: Junio C Hamano

Merge branch 'jt/interpret-branch-name-fallback'

2020-09-09T20:53:09Z

"git status" has trouble showing where it came from by interpreting reflog entries that recordcertain events, e.g. "checkout @{u}", and gives a hard/fatal error. Even though it inherently is impossible to give a correct answer because the reflog entries lose some information (e.g. "@{u}" does not record what branch the user was on hence which branch 'the upstream' needs to be computed, and even if the record were available, the relationship between branches may have changed), at least hide the error to allow "status" show its output. * jt/interpret-branch-name-fallback: wt-status: tolerate dangling marks refs: move dwim_ref() to header file sha1-name: replace unsigned int with option struct

wt-status: tolerate dangling marks

2020-09-02T21:39:25Z

When a user checks out the upstream branch of HEAD, the upstream branch not being a local branch, and then runs "git status", like this: git clone $URL client cd client git checkout @{u} git status no status is printed, but instead an error message: fatal: HEAD does not point to a branch (This error message when running "git branch" persists even after checking out other things - it only stops after checking out a branch.) This is because "git status" reads the reflog when determining the "HEAD detached" message, and thus attempts to DWIM "@{u}", but that doesn't work because HEAD no longer points to a branch. Therefore, when calculating the status of a worktree, tolerate dangling marks. This is done by adding an additional parameter to dwim_ref() and repo_dwim_ref(). Signed-off-by: Jonathan Tan Signed-off-by: Junio C Hamano

sha1-name: replace unsigned int with option struct

2020-09-02T21:39:17Z

In preparation for a future patch adding a boolean parameter to repo_interpret_branch_name(), which might be easily confused with an existing unsigned int parameter, refactor repo_interpret_branch_name() to take an option struct instead of the unsigned int parameter. The static function interpret_branch_mark() is also updated to take the option struct in preparation for that future patch, since it will also make use of the to-be-introduced boolean parameter. Signed-off-by: Jonathan Tan Signed-off-by: Junio C Hamano

Merge branch 'jk/leakfix'

2020-08-27T21:04:49Z

Code clean-up. * jk/leakfix: submodule--helper: fix leak of core.worktree value config: fix leak in git_config_get_expiry_in_days() config: drop git_config_get_string_const() config: fix leaks from git_config_get_string_const() checkout: fix leak of non-existent branch names submodule--helper: use strbuf_release() to free strbufs clear_pattern_list(): clear embedded hashmaps

config: drop git_config_get_string_const()

2020-08-17T22:35:47Z

As evidenced by the leak fixes in the previous commit, the "const" in git_config_get_string_const() clearly misleads people into thinking that it does not allocate a copy of the string. We can fix this by renaming it, but it's easier still to just drop it. Of the four remaining callers: - The one in git_config_parse_expiry() still needs to allocate, since that's what its callers expect. We can just use the non-const version and cast our pointer. Slightly ugly, but the damage is contained in one spot. - The two in apply are writing to global "const char *" variables, and need to continue allocating. We often mark these as const because we assign default string literals to them. But in this case we don't do that, so we can just declare them as real "char *" pointers and use the non-const version. - The call in checkout doesn't actually need a copy; it can just use the non-allocating "tmp" version of the function. The function is also mentioned in the MyFirstContribution document. We can swap that call out for the non-allocating "tmp" variant, which fits well in the example given. We'll drop the "configset" and "repo" variants, as well (which are unused). Note that this frees up the "const" name, so we could rename the "tmp" variant back to that. But let's give some time for topics in flight to adapt to the new code before doing so (if we do it too soon, the function semantics will change but the compiler won't alert us). Signed-off-by: Jeff King Signed-off-by: Junio C Hamano

Merge branch 'jk/reject-newer-extensions-in-v0' into master

2020-07-30T20:20:32Z

With the base fix to 2.27 regresion, any new extensions in a v0 repository would still be silently honored, which is not quite right. Instead, complain and die loudly. * jk/reject-newer-extensions-in-v0: verify_repository_format(): complain about new extensions in v0 repo

Merge branch 'jn/v0-with-extensions-fix' into master

2020-07-17T00:58:42Z

In 2.28-rc0, we corrected a bug that some repository extensions are honored by mistake even in a version 0 repositories (these configuration variables in extensions.* namespace were supposed to have special meaning in repositories whose version numbers are 1 or higher), but this was a bit too big a change. * jn/v0-with-extensions-fix: repository: allow repository format upgrade with extensions Revert "check_repository_format_gently(): refuse extensions for old repositories"

verify_repository_format(): complain about new extensions in v0 repo

2020-07-16T17:39:45Z

We made the mistake in the past of respecting extensions.* even when the repository format version was set to 0. This is bad because forgetting to bump the repository version means that older versions of Git (which do not know about our extensions) won't complain. I.e., it's not a problem in itself, but it means your repository is in a state which does not give you the protection you think you're getting from older versions. For compatibility reasons, we are stuck with that decision for existing extensions. However, we'd prefer not to extend the damage further. We can do that by catching any newly-added extensions and complaining about the repository format. Note that this is a pretty heavy hammer: we'll refuse to work with the repository at all. A lesser option would be to ignore (possibly with a warning) any new extensions. But because of the way the extensions are handled, that puts the burden on each new extension that is added to remember to "undo" itself (because they are handled before we know for sure whether we are in a v1 repo or not, since we don't insist on a particular ordering of config entries). So one option would be to rewrite that handling to record any new extensions (and their values) during the config parse, and then only after proceed to handle new ones only if we're in a v1 repository. But I'm not sure if it's worth the trouble: - ignoring extensions is likely to end up with broken results anyway (e.g., ignoring a proposed objectformat extension means parsing any object data is likely to encounter errors) - this is a sign that whatever tool wrote the extension field is broken. We may be better off notifying immediately and forcefully so that such tools don't even appear to work accidentally. The only downside is that fixing the situation is a little tricky, because programs like "git config" won't want to work with the repository. But: git config --file=.git/config core.repositoryformatversion 1 should still suffice. Signed-off-by: Jeff King Signed-off-by: Junio C Hamano

repository: allow repository format upgrade with extensions

2020-07-16T16:36:39Z

Now that we officially permit repository extensions in repository format v0, permit upgrading a repository with extensions from v0 to v1 as well. For example, this means a repository where the user has set "extensions.preciousObjects" can use "git fetch --filter=blob:none origin" to upgrade the repository to use v1 and the partial clone extension. To avoid mistakes, continue to forbid repository format upgrades in v0 repositories with an unrecognized extension. This way, a v0 user using a misspelled extension field gets a chance to correct the mistake before updating to the less forgiving v1 format. While we're here, make the error message for failure to upgrade the repository format a bit shorter, and present it as an error, not a warning. Reported-by: Huan Huan Chen Signed-off-by: Jonathan Nieder Signed-off-by: Junio C Hamano