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#ifndef COMMIT_SLAB_IMPL_H
#define COMMIT_SLAB_IMPL_H
#define MAYBE_UNUSED __attribute__((__unused__))
#define implement_static_commit_slab(slabname, elemtype) \
implement_commit_slab(slabname, elemtype, static MAYBE_UNUSED)
#define implement_shared_commit_slab(slabname, elemtype) \
implement_commit_slab(slabname, elemtype, )
#define implement_commit_slab(slabname, elemtype, scope) \
\
scope void init_ ##slabname## _with_stride(struct slabname *s, \
unsigned stride) \
{ \
unsigned int elem_size; \
if (!stride) \
stride = 1; \
s->stride = stride; \
elem_size = sizeof(elemtype) * stride; \
s->slab_size = COMMIT_SLAB_SIZE / elem_size; \
s->slab_count = 0; \
s->slab = NULL; \
} \
\
scope void init_ ##slabname(struct slabname *s) \
{ \
init_ ##slabname## _with_stride(s, 1); \
} \
\
scope void clear_ ##slabname(struct slabname *s) \
{ \
unsigned int i; \
for (i = 0; i < s->slab_count; i++) \
free(s->slab[i]); \
s->slab_count = 0; \
FREE_AND_NULL(s->slab); \
} \
\
scope elemtype *slabname## _at_peek(struct slabname *s, \
const struct commit *c, \
int add_if_missing) \
{ \
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) { \
unsigned int i; \
if (!add_if_missing) \
return NULL; \
REALLOC_ARRAY(s->slab, nth_slab + 1); \
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 (!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]; \
} \
\
scope elemtype *slabname## _at(struct slabname *s, \
const struct commit *c) \
{ \
return slabname##_at_peek(s, c, 1); \
} \
\
scope elemtype *slabname## _peek(struct slabname *s, \
const struct commit *c) \
{ \
return slabname##_at_peek(s, c, 0); \
} \
\
struct slabname
/*
* 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
*
* implement_commit_slab(indegree, int, static);
*
* 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.
*/
#endif /* COMMIT_SLAB_IMPL_H */
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