protobuf/upb/collections/map_sorter_internal.h

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// EVERYTHING BELOW THIS LINE IS INTERNAL - DO NOT USE /////////////////////////

#ifndef UPB_COLLECTIONS_MAP_SORTER_INTERNAL_H_
#define UPB_COLLECTIONS_MAP_SORTER_INTERNAL_H_

#include "upb/message/internal.h"

// Must be last.
#include "upb/port/def.inc"

#ifdef __cplusplus
extern "C" {
#endif

// _upb_mapsorter sorts maps and provides ordered iteration over the entries.
// Since maps can be recursive (map values can be messages which contain other
// maps), _upb_mapsorter can contain a stack of maps.

typedef struct {
  upb_tabent const** entries;
  int size;
  int cap;
} _upb_mapsorter;

typedef struct {
  int start;
  int pos;
  int end;
} _upb_sortedmap;

UPB_INLINE void _upb_mapsorter_init(_upb_mapsorter* s) {
  s->entries = NULL;
  s->size = 0;
  s->cap = 0;
}

UPB_INLINE void _upb_mapsorter_destroy(_upb_mapsorter* s) {
  if (s->entries) free(s->entries);
}

UPB_INLINE bool _upb_sortedmap_next(_upb_mapsorter* s, const upb_Map* map,
                                    _upb_sortedmap* sorted, upb_MapEntry* ent) {
  if (sorted->pos == sorted->end) return false;
  const upb_tabent* tabent = s->entries[sorted->pos++];
  upb_StringView key = upb_tabstrview(tabent->key);
  _upb_map_fromkey(key, &ent->k, map->key_size);
  upb_value val = {tabent->val.val};
  _upb_map_fromvalue(val, &ent->v, map->val_size);
  return true;
}

UPB_INLINE void _upb_mapsorter_popmap(_upb_mapsorter* s,
                                      _upb_sortedmap* sorted) {
  s->size = sorted->start;
}

bool _upb_mapsorter_pushmap(_upb_mapsorter* s, upb_FieldType key_type,
                            const upb_Map* map, _upb_sortedmap* sorted);

#ifdef __cplusplus
} /* extern "C" */
#endif

#include "upb/port/undef.inc"

#endif /* UPB_COLLECTIONS_MAP_SORTER_INTERNAL_H_ */