Arnav Bhate <bhatearnav@xxxxxxxxx> writes:
> -static int get_ours_cache_pos(const char *path, int pos)
> +static int get_ours_cache_pos(const char *path, unsigned int inverted_pos)
This renaming of parameter is not right.
At this point when the value comes to this function, it *IS* the
position, there is nothing inverted about it. It points at the
position in the .cache[] array where an cache_entry at a higher
stage would appear.
It is perfectly fine to state that the value that is returned from
index_name_pos() is potentially inverted. The function is given a
path name (without any stage information) and
- returns a non-negative number, the position in the .cache[] array,
where a cache_entry at stage #0 (i.e. an entry for a path that does
not require conflict resolution), or
- returns a negative number, when there is no such cache_entry
exists. The caller can "invert" the value to recover a position
in the .cache[] array, where a cache_entry for the path at stage
#0 _would_ _have_ been found, if existed. Due to the way the
cache entries are sorted in the .cache[] array, when you are
interested in finding cache entries for a path at higher stages,
like this function is, you can start scanning at this point until
you see an entry for a different path.
Calling the parameter "pos" is the right thing to do. The value
used to come here _could_ have been called "inverted", and the
result of (-inverted_pos-1) can be assigned to "pos". But because
the patch moves the inversion to the caller, what the code in the
while loop sees is no longer "inverted".
> {
> - int i = -pos - 1;
> -
> - while ((i < the_repository->index->cache_nr) && !strcmp(the_repository->index->cache[i]->name, path)) {
> - if (ce_stage(the_repository->index->cache[i]) == 2)
> - return i;
> - i++;
> + while ((inverted_pos < the_repository->index->cache_nr) && !strcmp(the_repository->index->cache[inverted_pos]->name, path)) {
> + if (ce_stage(the_repository->index->cache[inverted_pos]) == 2)
> + return inverted_pos;
> + inverted_pos++;
> }
> return -1;
> }
> @@ -58,7 +55,7 @@ static void print_error_files(struct string_list *files_list,
> int *errs)
> {
> if (files_list->nr) {
> - int i;
> + unsigned int i;
> struct strbuf err_msg = STRBUF_INIT;
>
> strbuf_addstr(&err_msg, main_msg);
> @@ -83,7 +80,7 @@ static void submodules_absorb_gitdir_if_needed(void)
>
> pos = index_name_pos(the_repository->index, name, strlen(name));
> if (pos < 0) {
Here is where the caller notices that index_name_pos() did not see a
stage #0 entry. This caller wants to see "ours" entry at stage #2,
so it "inverts" the returned value and asks the helper function if
it sees such an entry in the .cache[] array.
A handful of prerequisite pieces of knowledge to understand this
code are:
- The index (i.e. the .cache[] array) is sorted by full path name
(down from the top level of the working tree).
- The index can have at most one stage #0 entry for each path name.
When a stage #0 entry exists for a path name, there cannot be
higher stage entries (the path is called "resolved").
- The cache entries in the .cache[] array for the same path name
are sorted by their stage number.
- There can be at most one stage #2 entry for each path name, which
are called "ours". Entries at stage #1 are from common ancestor,
entries at stage #3 are from "their" tree. These higher (i.e.
more than zero) stage entries appear only for "conflicting"
paths in the .cache[] array.
With the understanding above, you can see why "our" position is
computed only when index_name_pos() returns negative in this hunk.
> - pos = get_ours_cache_pos(name, pos);
> + pos = get_ours_cache_pos(name, -pos - 1);
> if (pos < 0)
> continue;
> }
> @@ -131,7 +128,7 @@ static int check_local_mod(struct object_id *head, int index_only)
> * Skip unmerged entries except for populated submodules
> * that could lose history when removed.
> */
> - pos = get_ours_cache_pos(name, pos);
> + pos = get_ours_cache_pos(name, -pos - 1);
> if (pos < 0)
> continue;
The above hunks are perfectly fine.
> @@ -314,7 +311,7 @@ int cmd_rm(int argc,
> if (pathspec_needs_expanded_index(the_repository->index, &pathspec))
> ensure_full_index(the_repository->index);
>
> - for (i = 0; i < the_repository->index->cache_nr; i++) {
> + for (unsigned int i = 0; i < the_repository->index->cache_nr; i++) {
> const struct cache_entry *ce = the_repository->index->cache[i];
>
> if (!include_sparse &&
OK.
Thanks.
