[PATCH v2] merge-recursive.c: use string_list_sort instead of qsort

[Nguyễn Thái Ngọc Duy]

This started out to as a hunt for remaining qsort() calls after rs/qsort
series because qsort() API is a bit easy to get wrong (*). However,
since we have string_list_sort(), it's conceptually a better way to sort
here.

(*) In this particular case, it's even more confusing when you sort one
variable but you use the number of items and item size from an unrelated
variable (from a first glance)

Signed-off-by: Nguyễn Thái Ngọc Duy <pclo...@gmail.com>
---
 merge-recursive.c | 16 +++++++---------
 1 file changed, 7 insertions(+), 9 deletions(-)

diff --git a/merge-recursive.c b/merge-recursive.c
index 9041c2f..90e83bd 100644
--- a/merge-recursive.c
+++ b/merge-recursive.c
@@ -388,12 +388,10 @@ static struct string_list *get_unmerged(void)
        return unmerged;
 }
 
-static int string_list_df_name_compare(const void *a, const void *b)
+static int string_list_df_name_compare(const char *one, const char *two)
 {
-       const struct string_list_item *one = a;
-       const struct string_list_item *two = b;
-       int onelen = strlen(one->string);
-       int twolen = strlen(two->string);
+       int onelen = strlen(one);
+       int twolen = strlen(two);
        /*
         * Here we only care that entries for D/F conflicts are
         * adjacent, in particular with the file of the D/F conflict
@@ -406,8 +404,8 @@ static int string_list_df_name_compare(const void *a, const 
void *b)
         * since in other cases any changes in their order due to
         * sorting cause no problems for us.
         */
-       int cmp = df_name_compare(one->string, onelen, S_IFDIR,
-                                 two->string, twolen, S_IFDIR);
+       int cmp = df_name_compare(one, onelen, S_IFDIR,
+                                 two, twolen, S_IFDIR);
        /*
         * Now that 'foo' and 'foo/bar' compare equal, we have to make sure
         * that 'foo' comes before 'foo/bar'.
@@ -451,8 +449,8 @@ static void record_df_conflict_files(struct merge_options 
*o,
                string_list_append(&df_sorted_entries, next->string)->util =
                                   next->util;
        }
-       qsort(df_sorted_entries.items, entries->nr, sizeof(*entries->items),
-             string_list_df_name_compare);
+       df_sorted_entries.cmp = string_list_df_name_compare;
+       string_list_sort(&df_sorted_entries);
 
        string_list_clear(&o->df_conflict_file_set, 1);
        for (i = 0; i < df_sorted_entries.nr; i++) {
-- 
2.8.2.524.g6ff3d78