submodule: try harder to fetch needed sha1 by direct fetching sha1

diff --git a/commit-slab.h b/commit-slab.h
index f37ec3831f60cb9072d6cbf4f3d0126bc0681bf1..f84b449413d434b8145426503a98bcd4f9ad995f 100644 (file)
--- a/commit-slab.h
+++ b/commit-slab.h
@@ -15,7 +15,13 @@
  * - int *indegree_at(struct indegree *, struct commit *);
  *
  *   This function locates the data associated with the given commit in
- *   the indegree slab, and returns the pointer to it.
+ *   the indegree slab, and returns the pointer to it.  The location to
+ *   store the data is allocated as necessary.
+ *
+ * - int *indegree_peek(struct indegree *, struct commit *);
+ *
+ *   This function is similar to indegree_at(), but it will return NULL
+ *   until a call to indegree_at() was made for the commit.
  *
  * - void init_indegree(struct indegree *);
  *   void init_indegree_with_stride(struct indegree *, int);
@@ -80,8 +86,9 @@ static MAYBE_UNUSED void clear_ ##slabname(struct slabname *s)                \
        s->slab = NULL;                                                 \
 }                                                                      \
                                                                        \
-static MAYBE_UNUSED elemtype *slabname## _at(struct slabname *s,       \
-                                      const struct commit *c)          \
+static MAYBE_UNUSED elemtype *slabname## _at_peek(struct slabname *s,  \
+                                                 const struct commit *c, \
+                                                 int add_if_missing)   \
 {                                                                      \
        int nth_slab, nth_slot;                                         \
                                                                        \
@@ -90,16 +97,33 @@ static MAYBE_UNUSED elemtype *slabname## _at(struct slabname *s,    \
                                                                        \
        if (s->slab_count <= nth_slab) {                                \
                int i;                                                  \
+               if (!add_if_missing)                                    \
+                       return NULL;                                    \
                REALLOC_ARRAY(s->slab, nth_slab + 1);                   \
                stat_ ##slabname## realloc++;                           \
                for (i = s->slab_count; i <= nth_slab; i++)             \
                        s->slab[i] = NULL;                              \
                s->slab_count = nth_slab + 1;                           \
        }                                                               \
-       if (!s->slab[nth_slab])                                         \
+       if (!s->slab[nth_slab]) {                                       \
+               if (!add_if_missing)                                    \
+                       return NULL;                                    \
                s->slab[nth_slab] = xcalloc(s->slab_size,               \
                                            sizeof(**s->slab) * s->stride);             \
-       return &s->slab[nth_slab][nth_slot * s->stride];                                \
+       }                                                               \
+       return &s->slab[nth_slab][nth_slot * s->stride];                \
+}                                                                      \
+                                                                       \
+static MAYBE_UNUSED elemtype *slabname## _at(struct slabname *s,       \
+                                            const struct commit *c)    \
+{                                                                      \
+       return slabname##_at_peek(s, c, 1);                             \
+}                                                                      \
+                                                                       \
+static MAYBE_UNUSED elemtype *slabname## _peek(struct slabname *s,     \
+                                            const struct commit *c)    \
+{                                                                      \
+       return slabname##_at_peek(s, c, 0);                             \
 }                                                                      \
                                                                        \
 static int stat_ ##slabname## realloc