Jeff King <peff@xxxxxxxx> writes:
> On Fri, Sep 30, 2016 at 05:19:37PM -0700, Junio C Hamano wrote:
>
>> Introduce a mechanism, where we estimate the number of objects in
>> the repository upon the first request to abbreviate an object name
>> with the default setting and come up with a sane default for the
>> repository. Based on the expectation that we would see collision in
>> a repository with 2^(2N) objects when using object names shortened
>> to first N bits, use sufficient number of hexdigits to cover the
>> number of objects in the repository. Each hexdigit (4-bits) we add
>> to the shortened name allows us to have four times (2-bits) as many
>> objects in the repository.
I was idly browsing the draft release notes and then documentation
and noticed that, even though the new default is to auto-scale,
there is no mention of that in the documentation and there is no way
to explicitly ask for auto-scaling.
I wonder if we want to have something like this. I actually am
inclined to drop the change to config.c and remove the new mention
of "auto" in the documentation.
Documentation/config.txt | 9 +++++----
config.c | 14 ++++++++++----
2 files changed, 15 insertions(+), 8 deletions(-)
diff --git a/Documentation/config.txt b/Documentation/config.txt
index a0ab66aae7..b02f8a4025 100644
--- a/Documentation/config.txt
+++ b/Documentation/config.txt
@@ -783,10 +783,11 @@ core.sparseCheckout::
linkgit:git-read-tree[1] for more information.
core.abbrev::
- Set the length object names are abbreviated to. If unspecified,
- many commands abbreviate to 7 hexdigits, which may not be enough
- for abbreviated object names to stay unique for sufficiently long
- time.
+ Set the length object names are abbreviated to. If
+ unspecified or set to "auto", an appropriate value is
+ computed based on the approximate number of packed objects
+ in your repository, which hopefully is enough for
+ abbreviated object names to stay unique for some time.
add.ignoreErrors::
add.ignore-errors (deprecated)::
diff --git a/config.c b/config.c
index 83fdecb1bc..c363cca4a9 100644
--- a/config.c
+++ b/config.c
@@ -834,10 +834,16 @@ static int git_default_core_config(const char *var, const char *value)
}
if (!strcmp(var, "core.abbrev")) {
- int abbrev = git_config_int(var, value);
- if (abbrev < minimum_abbrev || abbrev > 40)
- return -1;
- default_abbrev = abbrev;
+ if (!value)
+ return config_error_nonbool(var);
+ if (!strcasecmp(value, "auto"))
+ default_abbrev = -1;
+ else {
+ int abbrev = git_config_int(var, value);
+ if (abbrev < minimum_abbrev || abbrev > 40)
+ return -1;
+ default_abbrev = abbrev;
+ }
return 0;
}