[PATCH v3 10/15] name-rev: use commit-slab for rev-name instead of commit->util

[Nguyễn Thái Ngọc Duy]

It's done so that commit->util can be removed. See more explanation in
the commit that removes commit->util.
---
 builtin/name-rev.c | 23 ++++++++++++++++++++---
 1 file changed, 20 insertions(+), 3 deletions(-)

diff --git a/builtin/name-rev.c b/builtin/name-rev.c
index 387ddf85d2..0eb440359d 100644
--- a/builtin/name-rev.c
+++ b/builtin/name-rev.c
@@ -6,6 +6,7 @@
 #include "refs.h"
 #include "parse-options.h"
 #include "sha1-lookup.h"
+#include "commit-slab.h"
 
 #define CUTOFF_DATE_SLOP 86400 /* one day */
 
@@ -17,11 +18,26 @@ typedef struct rev_name {
        int from_tag;
 } rev_name;
 
+define_commit_slab(commit_rev_name, struct rev_name *);
+
 static timestamp_t cutoff = TIME_MAX;
+static struct commit_rev_name rev_names;
 
 /* How many generations are maximally preferred over _one_ merge traversal? */
 #define MERGE_TRAVERSAL_WEIGHT 65535
 
+static struct rev_name *get_commit_rev_name(struct commit *commit)
+{
+       struct rev_name **slot = commit_rev_name_peek(&rev_names, commit);
+
+       return slot ? *slot : NULL;
+}
+
+static void set_commit_rev_name(struct commit *commit, struct rev_name *name)
+{
+       *commit_rev_name_at(&rev_names, commit) = name;
+}
+
 static int is_better_name(struct rev_name *name,
                          const char *tip_name,
                          timestamp_t taggerdate,
@@ -65,7 +81,7 @@ static void name_rev(struct commit *commit,
                int generation, int distance, int from_tag,
                int deref)
 {
-       struct rev_name *name = (struct rev_name *)commit->util;
+       struct rev_name *name = get_commit_rev_name(commit);
        struct commit_list *parents;
        int parent_number = 1;
        char *to_free = NULL;
@@ -84,7 +100,7 @@ static void name_rev(struct commit *commit,
 
        if (name == NULL) {
                name = xmalloc(sizeof(rev_name));
-               commit->util = name;
+               set_commit_rev_name(commit, name);
                goto copy_data;
        } else if (is_better_name(name, tip_name, taggerdate,
                                  generation, distance, from_tag)) {
@@ -296,7 +312,7 @@ static const char *get_rev_name(const struct object *o, 
struct strbuf *buf)
        if (o->type != OBJ_COMMIT)
                return get_exact_ref_match(o);
        c = (struct commit *) o;
-       n = c->util;
+       n = get_commit_rev_name(c);
        if (!n)
                return NULL;
 
@@ -413,6 +429,7 @@ int cmd_name_rev(int argc, const char **argv, const char 
*prefix)
                OPT_END(),
        };
 
+       init_commit_rev_name(&rev_names);
        git_config(git_default_config, NULL);
        argc = parse_options(argc, argv, prefix, opts, name_rev_usage, 0);
        if (all + transform_stdin + !!argc > 1) {
-- 
2.17.0.705.g3525833791