Merge branch 'ps/reftable-reusable-iterator'

Code clean-up to make the reftable iterator closer to be reusable.

* ps/reftable-reusable-iterator:
  reftable/merged: adapt interface to allow reuse of iterators
  reftable/stack: provide convenience functions to create iterators
  reftable/reader: adapt interface to allow reuse of iterators
  reftable/generic: adapt interface to allow reuse of iterators
  reftable/generic: move seeking of records into the iterator
  reftable/merged: simplify indices for subiterators
  reftable/merged: split up initialization and seeking of records
  reftable/reader: set up the reader when initializing table iterator
  reftable/reader: inline `reader_seek_internal()`
  reftable/reader: separate concerns of table iter and reftable reader
  reftable/reader: unify indexed and linear seeking
  reftable/reader: avoid copying index iterator
  reftable/block: use `size_t` to track restart point index

diff --cc refs/reftable-backend.c
Simple merge

diff --cc reftable/reader.c
index f23c8523db4cf75985e3389401e7ce6032196d53,bbdb4bdafa1f4283cbd271117522d64da8e0efb7..29c99e22694d422491913b8dd83e5668fec2bb72
--- 1/reftable/reader.c
--- 2/reftable/reader.c
+++ b/reftable/reader.c
@@@ -856,66 -820,3 +820,68 @@@ done
        reftable_reader_free(r);
        return err;
  }
-       struct table_iter ti = TABLE_ITER_INIT;
 +
 +int reftable_reader_print_blocks(const char *tablename)
 +{
 +      struct {
 +              const char *name;
 +              int type;
 +      } sections[] = {
 +              {
 +                      .name = "ref",
 +                      .type = BLOCK_TYPE_REF,
 +              },
 +              {
 +                      .name = "obj",
 +                      .type = BLOCK_TYPE_OBJ,
 +              },
 +              {
 +                      .name = "log",
 +                      .type = BLOCK_TYPE_LOG,
 +              },
 +      };
 +      struct reftable_block_source src = { 0 };
-               err = reader_start(r, &ti, sections[i].type, 0);
 +      struct reftable_reader *r = NULL;
++      struct table_iter ti = { 0 };
 +      size_t i;
 +      int err;
 +
 +      err = reftable_block_source_from_file(&src, tablename);
 +      if (err < 0)
 +              goto done;
 +
 +      err = reftable_new_reader(&r, &src, tablename);
 +      if (err < 0)
 +              goto done;
 +
++      table_iter_init(&ti, r);
++
 +      printf("header:\n");
 +      printf("  block_size: %d\n", r->block_size);
 +
 +      for (i = 0; i < ARRAY_SIZE(sections); i++) {
++              err = table_iter_seek_start(&ti, sections[i].type, 0);
 +              if (err < 0)
 +                      goto done;
 +              if (err > 0)
 +                      continue;
 +
 +              printf("%s:\n", sections[i].name);
 +
 +              while (1) {
 +                      printf("  - length: %u\n", ti.br.block_len);
 +                      printf("    restarts: %u\n", ti.br.restart_count);
 +
 +                      err = table_iter_next_block(&ti);
 +                      if (err < 0)
 +                              goto done;
 +                      if (err > 0)
 +                              break;
 +              }
 +      }
 +
 +done:
 +      reftable_reader_free(r);
 +      table_iter_close(&ti);
 +      return err;
 +}

diff --cc reftable/reftable-reader.h
Simple merge

diff --cc reftable/reftable-stack.h
Simple merge

diff --cc reftable/stack.c
Simple merge