[PATCH v4 0/8] sequencer API & users: fix widespread leaks

This series fixes various widespread leaks in the sequencer and its users (rebase, revert, cherry-pick). As a result 18 tests become leak-free in their entirety.

See the v1 for a longer general summary: https://lore.kernel.org/git/cover-00.10-00000000000-20221230T071741Z-avarab@gmail.com/

Changes since v3:

* Rebased for newer "master", there were some conflicts due to
  adjacent changes.
* Addressed Phillip's commit message comments (hopefully).

Branch & CI for this at: https://github.com/avar/git/tree/avar/leak-fixes-sequencer-rebase-4

Ævar Arnfjörð Bjarmason (8):
  rebase: use "cleanup" pattern in do_interactive_rebase()
  sequencer.c: split up sequencer_remove_state()
  sequencer API users: fix get_replay_opts() leaks
  builtin/revert.c: move free-ing of "revs" to replay_opts_release()
  builtin/rebase.c: fix "options.onto_name" leak
  sequencer.c: always free() the "msgbuf" in do_pick_commit()
  builtin/rebase.c: free() "options.strategy_opts"
  commit.c: free() revs.commit in get_fork_point()

 builtin/rebase.c                       | 22 ++++++++------
 builtin/revert.c                       |  8 ++---
 commit.c                               |  1 +
 sequencer.c                            | 42 ++++++++++++++++----------
 sequencer.h                            |  1 +
 t/t3405-rebase-malformed.sh            |  1 +
 t/t3412-rebase-root.sh                 |  1 +
 t/t3416-rebase-onto-threedots.sh       |  1 +
 t/t3419-rebase-patch-id.sh             |  1 +
 t/t3423-rebase-reword.sh               |  1 +
 t/t3425-rebase-topology-merges.sh      |  2 ++
 t/t3431-rebase-fork-point.sh           |  1 +
 t/t3432-rebase-fast-forward.sh         |  1 +
 t/t3437-rebase-fixup-options.sh        |  1 +
 t/t3438-rebase-broken-files.sh         |  2 ++
 t/t3501-revert-cherry-pick.sh          |  1 +
 t/t3502-cherry-pick-merge.sh           |  1 +
 t/t3503-cherry-pick-root.sh            |  1 +
 t/t3506-cherry-pick-ff.sh              |  1 +
 t/t3511-cherry-pick-x.sh               |  1 +
 t/t7402-submodule-rebase.sh            |  1 +
 t/t9106-git-svn-commit-diff-clobber.sh |  1 -
 t/t9164-git-svn-dcommit-concurrent.sh  |  1 -
 23 files changed, 61 insertions(+), 33 deletions(-)

Range-diff against v3:
1:  b223429df33 ! 1:  029fc5f4b8c rebase: use "cleanup" pattern in do_interactive_rebase()
    @@ Commit message
         Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
     
      ## builtin/rebase.c ##
    -@@ builtin/rebase.c: static void split_exec_commands(const char *cmd, struct string_list *commands)
    +@@ builtin/rebase.c: static int init_basic_state(struct replay_opts *opts, const char *head_name,
      
      static int do_interactive_rebase(struct rebase_options *opts, unsigned flags)
      {
    @@ builtin/rebase.c: static int do_interactive_rebase(struct rebase_options *opts,
      	}
      
     +cleanup:
    - 	string_list_clear(&commands, 0);
      	free(revisions);
      	free(shortrevisions);
    + 	todo_list_release(&todo_list);
2:  00c7f04363f = 2:  b0c9da95ca1 sequencer.c: split up sequencer_remove_state()
3:  e4a96898a68 ! 3:  dbac0501424 rebase & sequencer API: fix get_replay_opts() leak in "rebase"
    @@ Metadata
     Author: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
     
      ## Commit message ##
    -    rebase & sequencer API: fix get_replay_opts() leak in "rebase"
    +    sequencer API users: fix get_replay_opts() leaks
     
    -    Make the recently added replay_opts_release() function non-static and
    -    use it for freeing the "struct replay_opts" constructed by the
    -    get_replay_opts() function in "builtin/rebase.c". See [1] for the
    -    initial addition of get_replay_opts().
    +    Make the replay_opts_release() function added in the preceding commit
    +    non-static, and use it for freeing the "struct replay_opts"
    +    constructed for "rebase" and "revert".
     
         To safely call our new replay_opts_release() we'll need to stop
         calling it in sequencer_remove_state(), and instead call it where we
    @@ Commit message
         previously called sequencer_remove_state() would be a hassle.
     
         Using a FREE_AND_NULL() pattern would also work, as it would be safe
    -    replay_opts_release() repeatedly, but let's fix this properly instead,
    -    by having the owner of the data free() it.
    -
    -    See [2] for the initial implementation of "sequencer_remove_state()",
    -    which assumed that it should be removing the full (including on-disk)
    -    rebase state as a one-off.
    -
    -    1. 73fdc535d26 (rebase -i: use struct rebase_options to parse args,
    -       2019-04-17)
    -    2. 26ae337be11 (revert: Introduce --reset to remove sequencer state,
    -       2011-08-04)
    +    to call replay_opts_release() repeatedly. But let's fix this properly
    +    instead, by having the owner of the data free() it.
     
         Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
     
    @@ builtin/rebase.c: static int do_interactive_rebase(struct rebase_options *opts,
      
      cleanup:
     +	replay_opts_release(&replay);
    - 	string_list_clear(&commands, 0);
      	free(revisions);
      	free(shortrevisions);
    + 	todo_list_release(&todo_list);
     @@ builtin/rebase.c: static int run_sequencer_rebase(struct rebase_options *opts)
      		struct replay_opts replay_opts = get_replay_opts(opts);
      
4:  9f72cc6e46b = 4:  6b29d7d00c2 builtin/revert.c: move free-ing of "revs" to replay_opts_release()
5:  3d5c3152f69 ! 5:  f9c4d17fe70 builtin/rebase.c: fix "options.onto_name" leak
    @@ builtin/rebase.c: int cmd_rebase(int argc, const char **argv, const char *prefix
      	strbuf_release(&options.git_format_patch_opt);
      	free(squash_onto_name);
     +	free(keep_base_onto_name);
    - 	string_list_clear(&exec, 0);
      	string_list_clear(&strategy_options, 0);
      	return !!ret;
    + }
     
      ## t/t3416-rebase-onto-threedots.sh ##
     @@ t/t3416-rebase-onto-threedots.sh: test_description='git rebase --onto A...B'
6:  c07dc006c6d = 6:  5c2870ed2e6 sequencer.c: always free() the "msgbuf" in do_pick_commit()
7:  ee8262ab22a ! 7:  07ab875c3e2 builtin/rebase.c: free() "options.strategy_opts"
    @@ Commit message
      ## builtin/rebase.c ##
     @@ builtin/rebase.c: int cmd_rebase(int argc, const char **argv, const char *prefix)
      	free(options.gpg_sign_opt);
    - 	free(options.cmd);
    + 	string_list_clear(&options.exec, 0);
      	free(options.strategy);
     +	free(options.strategy_opts);
      	strbuf_release(&options.git_format_patch_opt);
8:  84343ea6bf6 = 8:  6ab2edcc135 commit.c: free() revs.commit in get_fork_point()