reftable/generic: drop interface

The `reftable_table` interface provides a generic infrastructure that
can abstract away whether the underlying table is a single table, or a
merged table. This abstraction can make it rather hard to reason about
the code. We didn't ever use it to implement the reftable backend, and
with the preceding patches in this patch series we in fact don't use it
at all anymore. Furthermore, it became somewhat useless with the recent
refactorings that made it possible to seek reftable iterators multiple
times, as these now provide generic access to tables for us. The
interface is thus redundant and only brings unnecessary complexity with
it.

Remove the `struct reftable_table` interface and its associated
functions.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Author: pks-t

Makefile

@@ -2674,7 +2674,6 @@ REFTABLE_OBJS += reftable/merged.o
 REFTABLE_OBJS += reftable/pq.o
 REFTABLE_OBJS += reftable/reader.o
 REFTABLE_OBJS += reftable/record.o
-REFTABLE_OBJS += reftable/generic.o
 REFTABLE_OBJS += reftable/stack.o
 REFTABLE_OBJS += reftable/tree.o
 REFTABLE_OBJS += reftable/writer.o

reftable/generic.c

@@ -11,7 +11,6 @@ license that can be found in the LICENSE file or at
 #include "system.h"
 
 #include "block.h"
-#include "generic.h"
 #include "constants.h"
 #include "reader.h"
 #include "reftable-error.h"

reftable/generic.h

@@ -14,7 +14,6 @@ license that can be found in the LICENSE file or at
 #include "record.h"
 
 #include "reftable-iterator.h"
-#include "reftable-generic.h"
 
 /*
  * The virtual function table for implementing generic reftable iterators.

reftable/iter.c

@@ -13,7 +13,6 @@ license that can be found in the LICENSE file or at
 #include "pq.h"
 #include "reader.h"
 #include "record.h"
-#include "generic.h"
 #include "reftable-merged.h"
 #include "reftable-error.h"
 #include "system.h"
@@ -270,40 +269,3 @@ uint32_t reftable_merged_table_hash_id(struct reftable_merged_table *mt)
 {
 	return mt->hash_id;
 }
-
-static void reftable_merged_table_init_iter_void(void *tab,
-						 struct reftable_iterator *it,
-						 uint8_t typ)
-{
-	merged_table_init_iter(tab, it, typ);
-}
-
-static uint32_t reftable_merged_table_hash_id_void(void *tab)
-{
-	return reftable_merged_table_hash_id(tab);
-}
-
-static uint64_t reftable_merged_table_min_update_index_void(void *tab)
-{
-	return reftable_merged_table_min_update_index(tab);
-}
-
-static uint64_t reftable_merged_table_max_update_index_void(void *tab)
-{
-	return reftable_merged_table_max_update_index(tab);
-}
-
-static struct reftable_table_vtable merged_table_vtable = {
-	.init_iter = reftable_merged_table_init_iter_void,
-	.hash_id = reftable_merged_table_hash_id_void,
-	.min_update_index = reftable_merged_table_min_update_index_void,
-	.max_update_index = reftable_merged_table_max_update_index_void,
-};
-
-void reftable_table_from_merged_table(struct reftable_table *tab,
-				      struct reftable_merged_table *merged)
-{
-	assert(!tab->ops);
-	tab->ops = &merged_table_vtable;
-	tab->table_arg = merged;
-}

reftable/iter.h

@@ -11,11 +11,9 @@ license that can be found in the LICENSE file or at
 #include "system.h"
 #include "block.h"
 #include "constants.h"
-#include "generic.h"
 #include "iter.h"
 #include "record.h"
 #include "reftable-error.h"
-#include "reftable-generic.h"
 
 uint64_t block_source_size(struct reftable_block_source *source)
 {
@@ -759,45 +757,6 @@ uint64_t reftable_reader_min_update_index(struct reftable_reader *r)
 	return r->min_update_index;
 }
 
-/* generic table interface. */
-
-static void reftable_reader_init_iter_void(void *tab,
-					   struct reftable_iterator *it,
-					   uint8_t typ)
-{
-	reader_init_iter(tab, it, typ);
-}
-
-static uint32_t reftable_reader_hash_id_void(void *tab)
-{
-	return reftable_reader_hash_id(tab);
-}
-
-static uint64_t reftable_reader_min_update_index_void(void *tab)
-{
-	return reftable_reader_min_update_index(tab);
-}
-
-static uint64_t reftable_reader_max_update_index_void(void *tab)
-{
-	return reftable_reader_max_update_index(tab);
-}
-
-static struct reftable_table_vtable reader_vtable = {
-	.init_iter = reftable_reader_init_iter_void,
-	.hash_id = reftable_reader_hash_id_void,
-	.min_update_index = reftable_reader_min_update_index_void,
-	.max_update_index = reftable_reader_max_update_index_void,
-};
-
-void reftable_table_from_reader(struct reftable_table *tab,
-				struct reftable_reader *reader)
-{
-	assert(!tab->ops);
-	tab->ops = &reader_vtable;
-	tab->table_arg = reader;
-}
-
 int reftable_reader_print_blocks(const char *tablename)
 {
 	struct {

reftable/merged.c

@@ -26,8 +26,6 @@ license that can be found in the LICENSE file or at
 /* A merged table is implements seeking/iterating over a stack of tables. */
 struct reftable_merged_table;
 
-/* A generic reftable; see below. */
-struct reftable_table;
 struct reftable_reader;
 
 /*
@@ -60,8 +58,4 @@ void reftable_merged_table_free(struct reftable_merged_table *m);
 /* return the hash ID of the merged table. */
 uint32_t reftable_merged_table_hash_id(struct reftable_merged_table *m);
 
-/* create a generic table from reftable_merged_table */
-void reftable_table_from_merged_table(struct reftable_table *tab,
-				      struct reftable_merged_table *table);
-
 #endif

reftable/reader.c

@@ -23,9 +23,6 @@
 /* The reader struct is a handle to an open reftable file. */
 struct reftable_reader;
 
-/* Generic table. */
-struct reftable_table;
-
 /* reftable_new_reader opens a reftable for reading. If successful,
  * returns 0 code and sets pp. The name is used for creating a
  * stack. Typically, it is the basename of the file. The block source
@@ -60,10 +57,6 @@ uint64_t reftable_reader_max_update_index(struct reftable_reader *r);
 /* return the min_update_index for a table */
 uint64_t reftable_reader_min_update_index(struct reftable_reader *r);
 
-/* creates a generic table from a file reader. */
-void reftable_table_from_reader(struct reftable_table *tab,
-				struct reftable_reader *reader);
-
 /* print blocks onto stdout for debugging. */
 int reftable_reader_print_blocks(const char *tablename);