Commit a9f1f1f9 authored by Duy Nguyen's avatar Duy Nguyen Committed by Junio C Hamano

commit-slab.h: code split

The struct declaration and implementation macros are moved to
commit-slab-hdr.h and commit-slab-impl.h respectively.

This right now is not needed for current users but if we make a public
commit-slab type, we may want to avoid including the slab
implementation in a header file which gets replicated in every c file
that includes it.
Signed-off-by: 's avatarJunio C Hamano <gitster@pobox.com>
parent ccdcbd54
#ifndef COMMIT_SLAB_HDR_H
#define COMMIT_SLAB_HDR_H
/* allocate ~512kB at once, allowing for malloc overhead */
#ifndef COMMIT_SLAB_SIZE
#define COMMIT_SLAB_SIZE (512*1024-32)
#endif
#define declare_commit_slab(slabname, elemtype) \
\
struct slabname { \
unsigned slab_size; \
unsigned stride; \
unsigned slab_count; \
elemtype **slab; \
}
/*
* 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_HDR_H */
#ifndef COMMIT_SLAB_IMPL_H
#define COMMIT_SLAB_IMPL_H
#define MAYBE_UNUSED __attribute__((__unused__))
#define implement_commit_slab(slabname, elemtype) \
\
static int stat_ ##slabname## realloc; \
\
static MAYBE_UNUSED 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; \
} \
\
static MAYBE_UNUSED void init_ ##slabname(struct slabname *s) \
{ \
init_ ##slabname## _with_stride(s, 1); \
} \
\
static MAYBE_UNUSED 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); \
} \
\
static MAYBE_UNUSED 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); \
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 (!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]; \
} \
\
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); \
} \
\
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);
*
* 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 */
#ifndef COMMIT_SLAB_H
#define COMMIT_SLAB_H
#include "commit-slab-decl.h"
#include "commit-slab-impl.h"
/*
* define_commit_slab(slabname, elemtype) creates boilerplate code to define
* a new struct (struct slabname) that is used to associate a piece of data
......@@ -41,114 +44,8 @@
* leaking memory.
*/
/* allocate ~512kB at once, allowing for malloc overhead */
#ifndef COMMIT_SLAB_SIZE
#define COMMIT_SLAB_SIZE (512*1024-32)
#endif
#define MAYBE_UNUSED __attribute__((__unused__))
#define define_commit_slab(slabname, elemtype) \
\
struct slabname { \
unsigned slab_size; \
unsigned stride; \
unsigned slab_count; \
elemtype **slab; \
}; \
static int stat_ ##slabname## realloc; \
\
static MAYBE_UNUSED 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; \
} \
\
static MAYBE_UNUSED void init_ ##slabname(struct slabname *s) \
{ \
init_ ##slabname## _with_stride(s, 1); \
} \
\
static MAYBE_UNUSED 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); \
} \
\
static MAYBE_UNUSED 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); \
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 (!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]; \
} \
\
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); \
} \
\
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
*
* define_commit_slab(indegree, int);
*
* 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 \
}
#define define_commit_slab(slabname, elemtype) \
declare_commit_slab(slabname, elemtype); \
implement_commit_slab(slabname, elemtype)
#endif /* COMMIT_SLAB_H */
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