snapshot_diff.h

/*
 * @file snapshot_diff.h
 * @brief Binary diff/patch for ParserSnapshots.
 *
 * Enables incremental composition: when a multi-extension daemon
 * startup composes the same set of grammars repeatedly with one
 * extension swapped, the diff between consecutive composed
 * snapshots is small.  Computing and applying the diff is faster
 * than rebuilding the full LALR table from grammar source.
 *
 * Available since v0.6.x.  No production consumer wires this into
 * compose_snapshots() yet; the API ships as a building block for
 * future incremental-composition work.
 */
 
#ifndef LIME_SNAPSHOT_DIFF_H
#define LIME_SNAPSHOT_DIFF_H
 
#include <stddef.h>
#include <stdint.h>
 
#ifdef __cplusplus
extern "C" {
#endif
 
struct ParserSnapshot;
 
typedef struct LimeSnapshotDiff LimeSnapshotDiff;
 
int lime_snapshot_diff(const struct ParserSnapshot *old_snap,
                       const struct ParserSnapshot *new_snap,
                       LimeSnapshotDiff           **out_diff,
                       char                       **error);
 
int lime_snapshot_apply_diff(const struct ParserSnapshot *base,
                             const LimeSnapshotDiff      *diff,
                             struct ParserSnapshot      **out_snap,
                             char                       **error);
 
void lime_snapshot_diff_release(LimeSnapshotDiff *diff);
 
size_t lime_snapshot_diff_summary(const LimeSnapshotDiff *diff,
                                  char                   *buf,
                                  size_t                  buflen);
 
#ifdef __cplusplus
}
#endif
 
#endif /* LIME_SNAPSHOT_DIFF_H */