There is no reason to use a temporary variable logfile.
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Split the logic that takes a single line of reflog entry in a
strbuf, parses the message, and calls the callback function out of
the loop into a separate helper function.
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

The old code allowed many references to be efficiently added to a
single directory, because it just appended the references to the
containing directory unsorted without doing any searching (and
therefore without requiring any intermediate sorting).  But the old
code was inefficient when a large number of subdirectories were added
to a directory, because the directory always had to be searched to see
if the new subdirectory already existed, and this search required the
directory to be sorted first.  The same was repeated for every new
subdirectory, so the time scaled like O(N^2), where N is the number of
subdirectories within a single directory.

In practice, references are often added to the ref_cache in
lexicographic order, for example when reading the packed-refs file.
So build some intelligence into add_entry_to_dir() to optimize for the
case of references and/or subdirectories being added in lexicographic
order: if the existing entries were already sorted, and the new entry
comes after the last existing entry, then adjust ref_dir::sorted to
reflect the fact that the ref_dir is still sorted.

Thanks to Peff for pointing out the performance regression that
inspired this change.
Signed-off-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

The search_ref_dir() function is about looking up an existing ref_entry in
a sorted array of ref_entry stored in dir->entries, but it still allocates
a new ref_entry and frees it before returning.  This is only because the
call to bsearch(3) was coded in a suboptimal way. Unlike the comparison
function given to qsort(3), the first parameter to its comparison function
does not need to point at an object that is shaped like an element in the
array.

Introduce a new comparison function that takes a counted string as the key
and an element in an array of ref_entry and give it to bsearch(), so that
we do not have to allocate a new ref_entry that we will never return to
the caller anyway.
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Convert the parameter subdirname of search_for_subdir() to a
length-limted string and then simply pass the interesting slice of the
refname from find_containing_dir(), thereby avoiding to duplicate the
string.
Signed-off-by: NRene Scharfe <rene.scharfe@lsrfire.ath.cx>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Signed-off-by: NRene Scharfe <rene.scharfe@lsrfire.ath.cx>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Signed-off-by: NRene Scharfe <rene.scharfe@lsrfire.ath.cx>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Do not call get_ref_dir() from within free_ref_entry(), because that
triggers the reading of loose refs, only for them to be freed
immediately.
Signed-off-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

The function used to return NULL when asked to find the containing
directory for a ref that does not exist, allowing the caller to
omit iteration altogether. But a misconversion in an earlier change
"refs.c: extract function search_for_subdir()" started returning the
top-level directory entry, forcing callers to walk everything.
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Instead of reading the whole directory of loose references the first
time any are needed, only read them on demand, one directory at a
time.

Use a new ref_entry flag bit REF_INCOMPLETE to indicate that the entry
represents a REF_DIR that hasn't been read yet.  Whenever any entries
from such a directory are needed, read all of the loose references
from that directory.
Signed-off-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

The ref_cache can now be read from the ref_dir.
Signed-off-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

This means that a directory ref_entry contains all of the information
needed by read_loose_refs().
Signed-off-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

That is what all the callers want, so give it to them.
Signed-off-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Convert all accesses of a ref_dir within a ref_entry to use this
function.  This function will later be responsible for reading loose
references from disk on demand.
Signed-off-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

The new name better describes the function's purpose, and also makes
the old name available for a more suitable purpose.
Signed-off-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Make it turtles all the way down.  This affects the loose and packed
fields of ref_cache instances.
Signed-off-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Signed-off-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

This simplifies the bookkeeping and allows an (artificial) restriction
on refname component length to be removed.
Signed-off-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Signed-off-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Previously, the "dir" argument to get_ref_dir() was a pointer to the
top-level ref_dir.  Change the function to expect a pointer to the
ref_dir corresponding to dirname.  This allows entries to be added
directly to dir, without having to recurse through the reference trie
each time (i.e., we can use add_entry_to_dir() instead of add_ref()).
Signed-off-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Signed-off-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

This removes some conditional code and makes it consistent with the
way that direntry names are stored.  Please note that this function is
never used on the top-level .git directory; it is always called for
directories at level .git/refs or deeper.
Signed-off-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Signed-off-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

This simplifies the bookkeeping and allows an (artificial) restriction
on refname component length to be removed.
Signed-off-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Signed-off-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

This helps remove \n from translatable strings
Signed-off-by: NNguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

If the base argument has a "/" chararacter, then only iterate over the
reference subdir whose name is the part up to the last "/".
Signed-off-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Store references hierarchically in a tree that matches the
pseudo-directory structure of the reference names.  Add a new kind of
ref_entry (with flag REF_DIR) to represent a whole subdirectory of
references.  Sort ref_dirs one subdirectory at a time.

NOTE: the dirs can now be sorted as a side-effect of other function
calls.  Therefore, it would be problematic to do something from a
each_ref_fn callback that could provoke the sorting of a directory
that is currently being iterated over (i.e., the directory containing
the entry that is being processed or any of its parents).

This is a bit far-fetched, because a directory is always sorted just
before being iterated over.  Therefore, read-only accesses cannot
trigger the sorting of a directory whose iteration has already
started.  But if a callback function would add a reference to a parent
directory of the reference in the iteration, then try to resolve a
reference under that directory, a re-sort could be triggered and cause
the iteration to work incorrectly.

Nevertheless...add a comment in refs.h warning against modifications
during iteration.
Signed-off-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Use the more usual indexing idiom for clarity.
Signed-off-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

This purely textual change is in preparation for storing references
hierarchically, when the old ref_array structure will represent one
"directory" of references.  Rename functions that deal with this
structure analogously, and also rename the structure's "refs" member
to "entries".
Signed-off-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

This change is obviously silly by itself, but it is a step towards
adding a second member to the union.
Signed-off-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Return 0 (instead of -1) for zero-length components.  Move the
interpretation of zero-length components as illegal to
check_refname_format().

This will make it easier to extend check_refname_format() to also
check whether directory names are valid.
Signed-off-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Add a function free_ref_entry().  This function will become nontrivial
when ref_entry (soon) becomes polymorphic.
Signed-off-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Save a bunch of lines of code and a couple of strlen() calls.
Signed-off-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

It costs a bit of boilerplate, but it means that the function can be
ignorant of how cached refs are stored.
Signed-off-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Extract function do_for_each_ref_in_arrays() from do_for_each_ref().
The new function will be a useful building block for storing refs
hierarchically.
Signed-off-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Extract function do_for_each_ref_in_array() from do_for_each_ref().
The new function will be a useful building block for storing refs
hierarchically.
Signed-off-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Set and clear current_ref within do_one_ref() instead of setting it
here and leaving it to somebody else to clear it.
Signed-off-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Reorder definitions in file: first check_refname_format() and helper
functions, then the functions for managing the ref_entry and ref_array
data structures, then ref_cache, then the more "business-logicky"
stuff.  No code is changed.
Signed-off-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

The extra_refs provided a kludgy way to create fake references at a
global level in the hope that they would only affect some particular
code path.  The last user of this API been rewritten, so strip this
stuff out before somebody else gets the bad idea of using it.
Signed-off-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>