Subject: [PATCH v4 0/3] make sure stash refreshes the index properly

From: Thomas Gummerer <[email-masked]>
Date: Wed, 11 Sep 2019 19:20:24 +0100

Compared to the previous round this round introduces a gentle flag for
refresh_and_write_{index,cache}, which should make this function
suitable for use in the Dscho's builtin-add-i series.  The latter will have to be 

I have also pushed this to https://github.com/tgummerer/git tg/stash-refresh-index

Range-diff below:

1:  7cc9f5fff4 ! 1:  2a7bebb20f factor out refresh_and_write_cache function
    @@ Commit message
         about failing to write the index.  However for other callers we're
         going to convert in subsequent patches we will need this distinction.
     
    +    Helped-by: Martin Ågren <[email-masked]>
    +    Helped-by: Johannes Schindelin <[email-masked]>
         Signed-off-by: Thomas Gummerer <[email-masked]>
     
      ## builtin/am.c ##
    @@ builtin/am.c: static void am_run(struct am_state *state, int resume)
      	unlink(am_path(state, "dirtyindex"));
      
     -	refresh_and_write_cache();
    -+	if (refresh_and_write_cache(REFRESH_QUIET, 0) < 0)
    ++	if (refresh_and_write_cache(REFRESH_QUIET, 0, 0) < 0)
     +		die(_("unable to write index file"));
      
      	if (repo_index_has_changes(the_repository, NULL, &sb)) {
    @@ cache.h: extern struct index_state the_index;
      #define add_file_to_cache(path, flags) add_file_to_index(&the_index, (path), (flags))
      #define chmod_cache_entry(ce, flip) chmod_index_entry(&the_index, (ce), (flip))
      #define refresh_cache(flags) refresh_index(&the_index, (flags), NULL, NULL, NULL)
    -+#define refresh_and_write_cache(refresh_flags, write_flags) repo_refresh_and_write_index(the_repository, (refresh_flags), (write_flags), NULL, NULL, NULL)
    ++#define refresh_and_write_cache(refresh_flags, write_flags, gentle) repo_refresh_and_write_index(the_repository, (refresh_flags), (write_flags), (gentle), NULL, NULL, NULL)
      #define ce_match_stat(ce, st, options) ie_match_stat(&the_index, (ce), (st), (options))
      #define ce_modified(ce, st, options) ie_modified(&the_index, (ce), (st), (options))
      #define cache_dir_exists(name, namelen) index_dir_exists(&the_index, (name), (namelen))
    @@ cache.h: void fill_stat_cache_info(struct index_state *istate, struct cache_entr
     + * 'COMMIT_LOCK | write_flags' is passed to 'write_locked_index()', so
     + * the lockfile is always either committed or rolled back.
     + *
    ++ * If 'gentle' is passed, errors locking the index are ignored.
    ++ *
     + * Return 1 if refreshing the index returns an error, -1 if writing
     + * the index to disk fails, 0 on success.
     + *
    -+ * Note that if refreshing the index returns an error, we don't write
    -+ * the result to disk.
    ++ * Note that if refreshing the index returns an error, we still write
    ++ * out the result (unless locking failed).
     + */
    -+int repo_refresh_and_write_index(struct repository*, unsigned int refresh_flags, unsigned int write_flags, const struct pathspec *, char *seen, const char *header_msg);
    ++int repo_refresh_and_write_index(struct repository*, unsigned int refresh_flags, unsigned int write_flags, int gentle, const struct pathspec *, char *seen, const char *header_msg);
     +
      struct cache_entry *refresh_cache_entry(struct index_state *, struct cache_entry *, unsigned int);
      
    @@ read-cache.c: static void show_file(const char * fmt, const char * name, int in_
      	printf(fmt, name);
      }
      
    -+int repo_refresh_and_write_index(struct  repository *repo,
    ++int repo_refresh_and_write_index(struct repository *repo,
     +				 unsigned int refresh_flags,
     +				 unsigned int write_flags,
    ++				 int gentle,
     +				 const struct pathspec *pathspec,
     +				 char *seen, const char *header_msg)
     +{
     +	struct lock_file lock_file = LOCK_INIT;
    ++	int fd, ret = 0;
     +
    -+	repo_hold_locked_index(repo, &lock_file, LOCK_DIE_ON_ERROR);
    -+	if (refresh_index(repo->index, refresh_flags, pathspec, seen, header_msg)) {
    -+		rollback_lock_file(&lock_file);
    -+		return 1;
    -+	}
    -+	if (write_locked_index(repo->index, &lock_file, COMMIT_LOCK | write_flags))
    ++	fd = repo_hold_locked_index(repo, &lock_file, 0);
    ++	if (!gentle && fd < 0)
     +		return -1;
    -+	return 0;
    ++	if (refresh_index(repo->index, refresh_flags, pathspec, seen, header_msg))
    ++		ret = 1;
    ++	if (0 <= fd && write_locked_index(repo->index, &lock_file, COMMIT_LOCK | write_flags))
    ++		ret = -1;
    ++	rollback_lock_file(&lock_file);
    ++	return ret;
     +}
     +
     +
2:  0367d938b1 ! 2:  555c982eae merge: use refresh_and_write_cache
    @@ builtin/merge.c: static int try_merge_strategy(const char *strategy, struct comm
     -	refresh_cache(REFRESH_QUIET);
     -	if (write_locked_index(&the_index, &lock,
     -			       COMMIT_LOCK | SKIP_IF_UNCHANGED))
    -+	if (refresh_and_write_cache(REFRESH_QUIET, SKIP_IF_UNCHANGED) < 0)
    ++	if (refresh_and_write_cache(REFRESH_QUIET, SKIP_IF_UNCHANGED, 0) < 0)
      		return error(_("Unable to write index."));
      
      	if (!strcmp(strategy, "recursive") || !strcmp(strategy, "subtree")) {
    @@ builtin/merge.c: static int merge_trivial(struct commit *head, struct commit_lis
     -	refresh_cache(REFRESH_QUIET);
     -	if (write_locked_index(&the_index, &lock,
     -			       COMMIT_LOCK | SKIP_IF_UNCHANGED))
    -+	if (refresh_and_write_cache(REFRESH_QUIET, SKIP_IF_UNCHANGED) < 0)
    ++	if (refresh_and_write_cache(REFRESH_QUIET, SKIP_IF_UNCHANGED, 0) < 0)
      		return error(_("Unable to write index."));
      
      	write_tree_trivial(&result_tree);
3:  8ed3df9fec ! 3:  cf74fe6053 stash: make sure to write refreshed cache
    @@ builtin/stash.c: static int do_apply_stash(const char *prefix, struct stash_info
      
      	read_cache_preload(NULL);
     -	if (refresh_cache(REFRESH_QUIET))
    -+	if (refresh_and_write_cache(REFRESH_QUIET, 0))
    ++	if (refresh_and_write_cache(REFRESH_QUIET, 0, 0))
      		return -1;
      
      	if (write_cache_as_tree(&c_tree, 0, NULL))
    @@ builtin/stash.c: static int do_apply_stash(const char *prefix, struct stash_info
      
      	if (quiet) {
     -		if (refresh_cache(REFRESH_QUIET))
    -+		if (refresh_and_write_cache(REFRESH_QUIET, 0))
    ++		if (refresh_and_write_cache(REFRESH_QUIET, 0, 0))
      			warning("could not refresh index");
      	} else {
      		struct child_process cp = CHILD_PROCESS_INIT;
    @@ builtin/stash.c: static int do_create_stash(const struct pathspec *ps, struct st
      
      	read_cache_preload(NULL);
     -	refresh_cache(REFRESH_QUIET);
    -+	if (refresh_and_write_cache(REFRESH_QUIET, 0) < 0) {
    ++	if (refresh_and_write_cache(REFRESH_QUIET, 0, 0) < 0) {
     +		ret = -1;
     +		goto done;
     +	}
    @@ builtin/stash.c: static int do_push_stash(const struct pathspec *ps, const char
      	}
      
     -	if (refresh_cache(REFRESH_QUIET)) {
    -+	if (refresh_and_write_cache(REFRESH_QUIET, 0)) {
    ++	if (refresh_and_write_cache(REFRESH_QUIET, 0, 0)) {
      		ret = -1;
      		goto done;
      	}

Thomas Gummerer (3):
  factor out refresh_and_write_cache function
  merge: use refresh_and_write_cache
  stash: make sure to write refreshed cache

 builtin/am.c     | 16 ++--------------
 builtin/merge.c  | 13 +++----------
 builtin/stash.c  | 11 +++++++----
 cache.h          | 18 ++++++++++++++++++
 read-cache.c     | 21 +++++++++++++++++++++
 t/t3903-stash.sh | 16 ++++++++++++++++
 6 files changed, 67 insertions(+), 28 deletions(-)

-- 
2.23.0.rc2.194.ge5444969c9