streaming.c: remove enum/function/vtbl indirection

Remove the indirection of discovering a function pointer to use via an
enum and virtual table. This refactors code added in
46bf043807 (streaming: a new API to read from the object store,
2011-05-11).

We can instead simply return an "open_istream_fn" for use from the
"istream_source()" selector function directly. This allows us to get
rid of the "incore", "loose" and "pack_non_delta" enum
variables. We'll return the functions instead.

The "stream_error" variable in that enum can likewise go in favor of
returning NULL, which is what the open_istream() was doing when it got
that value anyway.

We can thus remove the entire enum, and the "open_istream_tbl" virtual
table that (indirectly) referenced it.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit is contained in:
Ævar Arnfjörð Bjarmason 2021-05-05 14:33:29 +02:00 committed by Junio C Hamano
parent b65528360f
commit 0d9af06e36

View File

@ -8,13 +8,6 @@
#include "replace-object.h" #include "replace-object.h"
#include "packfile.h" #include "packfile.h"
enum input_source {
stream_error = -1,
incore = 0,
loose = 1,
pack_non_delta = 2
};
typedef int (*open_istream_fn)(struct git_istream *, typedef int (*open_istream_fn)(struct git_istream *,
struct repository *, struct repository *,
struct object_info *, struct object_info *,
@ -424,13 +417,7 @@ static open_method_decl(incore)
* static helpers variables and functions for users of streaming interface * static helpers variables and functions for users of streaming interface
*****************************************************************************/ *****************************************************************************/
static open_istream_fn open_istream_tbl[] = { static open_istream_fn istream_source(struct repository *r,
open_istream_incore,
open_istream_loose,
open_istream_pack_non_delta,
};
static enum input_source istream_source(struct repository *r,
const struct object_id *oid, const struct object_id *oid,
enum object_type *type, enum object_type *type,
struct object_info *oi) struct object_info *oi)
@ -442,21 +429,20 @@ static enum input_source istream_source(struct repository *r,
oi->sizep = &size; oi->sizep = &size;
status = oid_object_info_extended(r, oid, oi, 0); status = oid_object_info_extended(r, oid, oi, 0);
if (status < 0) if (status < 0)
return stream_error; return NULL;
switch (oi->whence) { switch (oi->whence) {
case OI_LOOSE: case OI_LOOSE:
return loose; return open_istream_loose;
case OI_PACKED: case OI_PACKED:
if (!oi->u.packed.is_delta && big_file_threshold < size) if (!oi->u.packed.is_delta && big_file_threshold < size)
return pack_non_delta; return open_istream_pack_non_delta;
/* fallthru */ /* fallthru */
default: default:
return incore; return open_istream_incore;
} }
} }
/**************************************************************** /****************************************************************
* Users of streaming interface * Users of streaming interface
****************************************************************/ ****************************************************************/
@ -482,13 +468,13 @@ struct git_istream *open_istream(struct repository *r,
struct git_istream *st; struct git_istream *st;
struct object_info oi = OBJECT_INFO_INIT; struct object_info oi = OBJECT_INFO_INIT;
const struct object_id *real = lookup_replace_object(r, oid); const struct object_id *real = lookup_replace_object(r, oid);
enum input_source src = istream_source(r, real, type, &oi); open_istream_fn open_fn = istream_source(r, real, type, &oi);
if (src < 0) if (!open_fn)
return NULL; return NULL;
st = xmalloc(sizeof(*st)); st = xmalloc(sizeof(*st));
if (open_istream_tbl[src](st, r, &oi, real, type)) { if (open_fn(st, r, &oi, real, type)) {
if (open_istream_incore(st, r, &oi, real, type)) { if (open_istream_incore(st, r, &oi, real, type)) {
free(st); free(st);
return NULL; return NULL;