*
* After including this header file, using:
*
- * define_commit_slab(indegee, int);
+ * define_commit_slab(indegree, int);
*
* will let you call the following functions:
*
* - 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);
\
static MAYBE_UNUSED void clear_ ##slabname(struct slabname *s) \
{ \
- int i; \
+ unsigned int i; \
for (i = 0; i < s->slab_count; i++) \
free(s->slab[i]); \
s->slab_count = 0; \
- free(s->slab); \
- s->slab = NULL; \
+ FREE_AND_NULL(s->slab); \
} \
\
-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; \
+ unsigned int nth_slab, nth_slot; \
\
nth_slab = c->index / s->slab_size; \
nth_slot = c->index % s->slab_size; \
\
if (s->slab_count <= nth_slab) { \
- int i; \
- s->slab = xrealloc(s->slab, \
- (nth_slab + 1) * sizeof(*s->slab)); \
+ unsigned 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 int stat_ ##slabname## realloc
+static MAYBE_UNUSED elemtype *slabname## _peek(struct slabname *s, \
+ const struct commit *c) \
+{ \
+ return slabname##_at_peek(s, c, 0); \
+} \
+ \
+struct slabname
/*
- * Note that this seemingly redundant second declaration is required
+ * Note that this redundant forward declaration is required
* to allow a terminating semicolon, which makes instantiations look
* like function declarations. I.e., the expansion of
*
* define_commit_slab(indegree, int);
*
- * ends in 'static int stat_indegreerealloc;'. This would otherwise
+ * ends in 'struct indegree;'. This would otherwise
* be a syntax error according (at least) to ISO C. It's hard to
* catch because GCC silently parses it by default.
*/
+/*
+ * Statically initialize a commit slab named "var". Note that this
+ * evaluates "stride" multiple times! Example:
+ *
+ * struct indegree indegrees = COMMIT_SLAB_INIT(1, indegrees);
+ *
+ */
+#define COMMIT_SLAB_INIT(stride, var) { \
+ COMMIT_SLAB_SIZE / sizeof(**((var).slab)) / (stride), \
+ (stride), 0, NULL \
+}
+
#endif /* COMMIT_SLAB_H */
projects / platform / upstream / git.git / blobdiff