On Sun, Apr 16, 2017 at 05:41:25PM +0700, Nguyễn Thái Ngọc Duy wrote:
> If setup_git_directory() and friends have not been called,
> get_git_dir() (because of includeIf.gitdir:XXX) would lead to
>
> die("BUG: setup_git_env called without repository");
>
> There are two cases when a config file could be read before $GIT_DIR is
> located. The first one is check_repository_format(), where we read just
> the one file $GIT_DIR/config to check if we could understand this
> repository. This case should be safe. The concerned variables should
> never be hidden away behind includes anyway.
Right, we should not even have respect_includes turned on for that case.
> The second one is triggered in check_pager_config() when we're about to
> run an external git command. We might be able to find $GIT_DIR in this
> case, which is exactly what read_early_config() does (and also is the
> what check_pager_config() uses). Conditional includes and
s/the what/what/
> diff --git a/cache.h b/cache.h
> index e29a093839..27b7286f99 100644
> --- a/cache.h
> +++ b/cache.h
> @@ -1884,6 +1884,8 @@ enum config_origin_type {
>
> struct config_options {
> unsigned int respect_includes : 1;
> + unsigned int early_config : 1;
> + const char *git_dir; /* only valid when early_config is true */
> };
Why do we need both the flag and the string? Later, you do:
> -static int include_by_gitdir(const char *cond, size_t cond_len, int icase)
> +static int include_by_gitdir(const struct config_options *opts,
> + const char *cond, size_t cond_len, int icase)
> {
> struct strbuf text = STRBUF_INIT;
> struct strbuf pattern = STRBUF_INIT;
> int ret = 0, prefix;
>
> - strbuf_add_absolute_path(&text, get_git_dir());
> + if (!opts->early_config)
> + strbuf_add_absolute_path(&text, get_git_dir());
> + else if (opts->git_dir)
> + strbuf_add_absolute_path(&text, opts->git_dir);
> + else
> + goto done;
So we call get_git_dir() always when we're not in early config. Even if
we don't have a git dir! Doesn't this mean that programs operating
outside of a repo will still hit the BUG? I.e.:
git config --global includeif.gitdir:/whatever.path foo
cd /not/a/git/dir
git diff --no-index foo bar
?
I think instead the logic should be:
if (opts->git_dir)
strbuf_add_absolute_path(&text, opts->git_dir);
else if (have_git_dir())
strbuf_add_absolute_path(&text, get_git_dir());
else
goto done;
I'd also be tempted to call the option field "override_git_dir" or
something to indicate that it takes precedence over the normal one. With
the current code it doesn't matter, because we set it only to the result
of the discovered dir.
> @@ -1615,15 +1626,21 @@ void read_early_config(config_fn_t cb, void *data)
> * notably, the current working directory is still the same after the
> * call).
> */
> - if (!have_git_dir() && discover_git_directory(&buf)) {
> + else if (discover_git_directory(&buf))
> + opts.git_dir = to_free = strbuf_detach(&buf, NULL);
This to_free seemed redundant to me at first; why not just hold on to
the strbuf and release it later?
The answer is that we reuse the strbuf to generate the config-file path
later. However, by detaching, we clear the strbuf. So later when we
use it:
> + if (opts.git_dir) {
> struct git_config_source repo_config;
>
> memset(&repo_config, 0, sizeof(repo_config));
> - strbuf_addstr(&buf, "/config");
> + strbuf_addf(&buf, "%s/config", opts.git_dir);
> repo_config.file = buf.buf;
> git_config_with_options(cb, data, &repo_config, &opts);
> }
...we have to re-add the git_dir.
Might it be simpler to just xstrdup() to opts.git_dir, and then leave
this later code alone?
That said, I actually think in the long run that
git_config_with_options() should compute the repo_config itself from our
git_dir parameter. That lets us fix a very subtle bug in
read_early_config(). The problem is that the function works like this:
1. Run git_config_with_options(), hitting the usual sources in order
2. If we didn't have a git-dir, run it again just for our discovered
repo-config
That has two implications:
- the config callback will see keys from ~/.gitconfig twice, once for
each run. This is usually OK because the only early config we care
about uses last-one-wins semantics (so no list-appending).
- the repo-level config is read last, so by last-one-wins it takes
precedence over ~/.gitconfig. Good. But it should have _less_
precedence than command-line config, and it doesn't.
You can see the second problem with:
# random external
cat >git-foo <<-\EOF
#!/bin/sh
echo foo
EOF
chmod +x git-foo
PATH=$PWD:$PATH
git init
git config pager.foo 'sed s/^/repo:/'
git -c pager.foo='sed s/^/cmdline:/' foo
That command should prefer the cmdline config, but it doesn't.
The fix is something like what's below, which is easy on top of your new
options struct. I can wrap it up with a config message and test on top
of your series.
diff --git a/config.c b/config.c
index f323b9628..5dda6e8ca 100644
--- a/config.c
+++ b/config.c
@@ -1502,12 +1502,20 @@ int git_config_system(void)
return !git_env_bool("GIT_CONFIG_NOSYSTEM", 0);
}
-static int do_git_config_sequence(config_fn_t fn, void *data)
+static int do_git_config_sequence(config_fn_t fn, void *data,
+ const char *override_repo_dir)
{
int ret = 0;
char *xdg_config = xdg_config_home("config");
char *user_config = expand_user_path("~/.gitconfig");
- char *repo_config = have_git_dir() ? git_pathdup("config") : NULL;
+ char *repo_config;
+
+ if (override_repo_dir)
+ repo_config = mkpathdup("%s/config", override_repo_dir);
+ else if (have_git_dir())
+ repo_config = git_pathdup("config");
+ else
+ repo_config = NULL;
current_parsing_scope = CONFIG_SCOPE_SYSTEM;
if (git_config_system() && !access_or_die(git_etc_gitconfig(), R_OK, 0))
@@ -1561,7 +1569,7 @@ int git_config_with_options(config_fn_t fn, void *data,
else if (config_source && config_source->blob)
return git_config_from_blob_ref(fn, config_source->blob, data);
- return do_git_config_sequence(fn, data);
+ return do_git_config_sequence(fn, data, opts->git_dir);
}
static void git_config_raw(config_fn_t fn, void *data)
@@ -1631,14 +1639,6 @@ void read_early_config(config_fn_t cb, void *data)
git_config_with_options(cb, data, NULL, &opts);
- if (opts.git_dir) {
- struct git_config_source repo_config;
-
- memset(&repo_config, 0, sizeof(repo_config));
- strbuf_addf(&buf, "%s/config", opts.git_dir);
- repo_config.file = buf.buf;
- git_config_with_options(cb, data, &repo_config, &opts);
- }
strbuf_release(&buf);
free(to_free);
}