prune_remote(): exit early if there are no stale references

Aside from making the logic clearer, this avoids a call to
warn_dangling_symrefs(), which always does a for_each_rawref()
iteration.

Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
prune_remote(): initialize both delete_refs lists in a single loop

Also free them together at the end of the function.

In a moment, the array version will become redundant. Managing them
together makes later steps more obvious.

Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
prune_remote(): sort delete_refs_list references en masse

Inserting items into a list in sorted order is O(N^2) whereas
appending them unsorted and then sorting the list all at once is
O(N lg N).

string_list_insert() also removes duplicates, and this change loses
that functionality. But the strings in this list, which ultimately
come from a for_each_ref() iteration, cannot contain duplicates.

Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
repack_without_refs(): make the refnames argument a string_list

Most of the callers have string_lists available already, whereas two
of them had to read data out of a string_list into an array of strings
just to call this function. So change repack_without_refs() to take
the list of refnames to omit as a string_list, and change the callers
accordingly.

Suggested-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
prune_remote(): rename local variable

Rename "delete_refs_list" to "refs_to_prune". The new name is more
self-explanatory.

Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
prune_remote(): iterate using for_each_string_list_item()

Iterate over refs_to_prune using for_each_string_list_item() rather
than writing out the loop in longhand.

Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
sort_string_list(): rename to string_list_sort()

The new name is more consistent with the names of other
string_list-related functions.

Suggested-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Merge branch 'mh/simplify-repack-without-refs' into jch

* mh/simplify-repack-without-refs:
  sort_string_list(): rename to string_list_sort()
  prune_remote(): iterate using for_each_string_list_item()
  prune_remote(): rename local variable
  repack_without_refs(): make the refnames argument a string_list
  prune_remote(): sort delete_refs_list references en masse
  prune_remote(): initialize both delete_refs lists in a single loop
  prune_remote(): exit early if there are no stale references
Merge branch 'jk/lock-ref-sha1-basic-return-errors' into jch

* jk/lock-ref-sha1-basic-return-errors:
  lock_ref_sha1_basic: do not die on locking errors
Merge branch 'sb/ref-transaction-unify-to-update' into jch

* sb/ref-transaction-unify-to-update:
  refs.c: make ref_transaction_delete a wrapper for ref_transaction_update
  refs.c: make ref_transaction_create a wrapper for ref_transaction_update
Merge branch 'jk/colors-fix' into jch

* jk/colors-fix:
  t4026: test "normal" color
  config: fix parsing of "git config --get-color some.key -1"
  docs: describe ANSI 256-color mode
Merge branch 'jk/colors' into jch

* jk/colors:
  diff-highlight: allow configurable colors
  parse_color: recognize "no$foo" to clear the $foo attribute
  parse_color: support 24-bit RGB values
  parse_color: refactor color storage
Merge branch 'sb/copy-fd-errno' into jch

* sb/copy-fd-errno:
  copy.c: make copy_fd preserve meaningful errno
Merge branch 'da/difftool-mergetool-simplify-reporting-status' into jch

* da/difftool-mergetool-simplify-reporting-status:
  mergetools: stop setting $status in merge_cmd()
  mergetool: simplify conditionals
  difftool--helper: add explicit exit statement
  mergetool--lib: remove use of $status global
  mergetool--lib: remove no-op assignment to $status from setup_user_tool