cache-tree: create/update cache-tree on checkout

When git checkout checks out a branch, create or update the
cache-tree so that subsequent operations are faster.

update_main_cache_tree learned a new flag, WRITE_TREE_REPAIR.  When
WRITE_TREE_REPAIR is set, portions of the cache-tree which do not
correspond to existing tree objects are invalidated (and portions which
do are marked as valid).  No new tree objects are created.

Signed-off-by: David Turner <dturner@twitter.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
test-dump-cache-tree: invalid trees are not errors

Do not treat known-invalid trees as errors even when their subtree_nr is
incorrect.  Because git already knows that these trees are invalid,
an incorrect subtree_nr will not cause problems.

Add a couple of comments.

Signed-off-by: David Turner <dturner@twitter.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
cache-tree: subdirectory tests

Add tests to confirm that invalidation of subdirectories neither over-
nor under-invalidates.

Signed-off-by: David Turner <dturner@twitter.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
cache-tree: Write updated cache-tree after commit

During the commit process, update the cache-tree. Write this updated
cache-tree so that it's ready for subsequent commands.

Add test code which demonstrates that git commit now writes the cache
tree.  Make all tests test the entire cache-tree, not just the root
level.

Signed-off-by: David Turner <dturner@twitter.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
config.c: mark error and warnings strings for translation

Signed-off-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Reviewed-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
config.c: fix accuracy of line number in errors

If a callback returns a negative value to `git_config*()` family,
they call `die()` while printing the line number and the file name.
Currently the printed line number is off by one, thus printing the
wrong line number.

Make `linenr` point to the line we just parsed during the call
to callback to get accurate line number in error messages.

Commit-message-by: Tanay Abhra <tanayabh@gmail.com>
Signed-off-by: Tanay Abhra <tanayabh@gmail.com>
Signed-off-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
add line number and file name info to `config_set`

Store file name and line number for each key-value pair in the cache
during parsing of the configuration files.

Signed-off-by: Tanay Abhra <tanayabh@gmail.com>
Reviewed-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
change `git_config()` return value to void

Currently `git_config()` returns an integer signifying an error code.
During rewrites of the function most of the code was shifted to
`git_config_with_options()`. `git_config_with_options()` normally
returns positive values if its `config_source` parameter is set as NULL,
as most errors are fatal, and non-fatal potential errors are guarded
by "if" statements that are entered only when no error is possible.

Still a negative value can be returned in case of race condition between
`access_or_die()` & `git_config_from_file()`. Also, all callers of
`git_config()` ignore the return value except for one case in branch.c.

Change `git_config()` return value to void and make it die if it receives
a negative value from `git_config_with_options()`.

Original-patch-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Tanay Abhra <tanayabh@gmail.com>
Reviewed-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
config: add `git_die_config()` to the config-set API

Add `git_die_config` that dies printing the line number and the file name
of the highest priority value for the configuration variable `key`. A custom
error message is also printed before dying, specified by the caller, which can
be skipped if `err` argument is set to NULL.

It has usage in non-callback based config value retrieval where we can
raise an error and die if there is a semantic error.
For example,

	if (!git_config_get_value(key, &value)){
		if (!strcmp(value, "foo"))
			git_config_die(key, "value: `%s` is illegal", value);
		else
			/* do work */
	}

Signed-off-by: Tanay Abhra <tanayabh@gmail.com>
Reviewed-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
rewrite git_config() to use the config-set API

Of all the functions in `git_config*()` family, `git_config()` has the
most invocations in the whole code base. Each `git_config()` invocation
causes config file rereads which can be avoided using the config-set API.

Use the config-set API to rewrite `git_config()` to use the config caching
layer to avoid config file rereads on each invocation during a git process
lifetime. First invocation constructs the cache, and after that for each
successive invocation, `git_config()` feeds values from the config cache
instead of rereading the configuration files.

Signed-off-by: Tanay Abhra <tanayabh@gmail.com>
Reviewed-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
add a test for semantic errors in config files

Semantic errors (for example, for alias.* variables NULL values are
not allowed) in configuration files cause a die printing the line
number and file name of the offending value.

Add a test documenting that such errors cause a die printing the
accurate line number and file name.

Signed-off-by: Tanay Abhra <tanayabh@gmail.com>
Reviewed-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
add tests for `git_config_get_string_const()`

Add tests for `git_config_get_string_const()`, check whether it
dies printing the line number and the file name if a NULL
value is retrieved for the given key.

Signed-off-by: Tanay Abhra <tanayabh@gmail.com>
Reviewed-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
daemon.c: replace `git_config()` with `git_config_get_bool()` family

Use `git_config_get_bool()` family instead of `git_config()` to take advantage of
the config-set API which provides a cleaner control flow.

Signed-off-by: Tanay Abhra <tanayabh@gmail.com>
Reviewed-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
http-backend.c: replace `git_config()` with `git_config_get_bool()` family

Use `git_config_get_bool()` family instead of `git_config()` to take advantage of
the config-set API which provides a cleaner control flow.

Signed-off-by: Tanay Abhra <tanayabh@gmail.com>
Reviewed-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
read-cache.c: replace `git_config()` with `git_config_get_*()` family

Use `git_config_get_*()` family instead of `git_config()` to take
advantage of the config-set API which provides a cleaner control flow.

Use an intermediate value, as `version` can not be used directly in
git_config_get_int() due to incompatible type.

Signed-off-by: Tanay Abhra <tanayabh@gmail.com>
Reviewed-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
archive.c: replace `git_config()` with `git_config_get_bool()` family

Use `git_config_get_bool()` family instead of `git_config()` to take advantage of
the config-set API which provides a cleaner control flow.

Signed-off-by: Tanay Abhra <tanayabh@gmail.com>
Reviewed-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
fetchpack.c: replace `git_config()` with `git_config_get_*()` family

Use `git_config_get_*()` family instead of `git_config()` to take advantage of
the config-set API which provides a cleaner control flow.

Signed-off-by: Tanay Abhra <tanayabh@gmail.com>
Reviewed-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
rerere.c: replace `git_config()` with `git_config_get_*()` family

Use `git_config_get_*()` family instead of `git_config()` to take advantage of
the config-set API which provides a cleaner control flow.

Signed-off-by: Tanay Abhra <tanayabh@gmail.com>
Reviewed-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
builtin/gc.c: replace `git_config()` with `git_config_get_*()` family

Use `git_config_get_*()` family instead of `git_config()` to take advantage of
the config-set API which provides a cleaner control flow.

Signed-off-by: Tanay Abhra <tanayabh@gmail.com>
Reviewed-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
pager.c: replace `git_config()` with `git_config_get_value()`

Use `git_config_get_value()` instead of `git_config()` to take advantage of
the config-set API which provides a cleaner control flow.

Signed-off-by: Tanay Abhra <tanayabh@gmail.com>
Reviewed-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>