1 files changed, 26 insertions, 8 deletions

diff --git a/src/node/blockstorage.h b/src/node/blockstorage.h
index 11445aa22e..e4b9657372 100644
--- a/src/node/blockstorage.h
+++ b/src/node/blockstorage.h
@@ -13,6 +13,7 @@
 
 #include <atomic>
 #include <cstdint>
+#include <unordered_map>
 #include <vector>
 
 extern RecursiveMutex cs_main;
@@ -65,6 +66,10 @@ struct CBlockIndexHeightOnlyComparator {
     bool operator()(const CBlockIndex* pa, const CBlockIndex* pb) const;
 };
 
+struct PruneLockInfo {
+    int height_first{std::numeric_limits<int>::max()}; //! Height of earliest block that should be kept and not pruned
+};
+
 /**
  * Maintains a tree of blocks (stored in `m_block_index`) which is consulted
  * to determine where the most-work tip is.
@@ -78,6 +83,13 @@ class BlockManager
     friend ChainstateManager;
 
 private:
+    /**
+     * Load the blocktree off disk and into memory. Populate certain metadata
+     * per index entry (nStatus, nChainWork, nTimeMax, etc.) as well as peripheral
+     * collections like m_dirty_blockindex.
+     */
+    bool LoadBlockIndex(const Consensus::Params& consensus_params)
+        EXCLUSIVE_LOCKS_REQUIRED(cs_main);
     void FlushBlockFile(bool fFinalize = false, bool finalize_undo = false);
     void FlushUndoFile(int block_file, bool finalize = false);
     bool FindBlockPos(FlatFilePos& pos, unsigned int nAddSize, unsigned int nHeight, CChain& active_chain, uint64_t nTime, bool fKnown);
@@ -118,6 +130,14 @@ private:
     /** Dirty block file entries. */
     std::set<int> m_dirty_fileinfo;
 
+    /**
+     * Map from external index name to oldest block that must not be pruned.
+     *
+     * @note Internally, only blocks at height (height_first - PRUNE_LOCK_BUFFER - 1) and
+     * below will be pruned, but callers should avoid assuming any particular buffer size.
+     */
+    std::unordered_map<std::string, PruneLockInfo> m_prune_locks GUARDED_BY(::cs_main);
+
 public:
     BlockMap m_block_index GUARDED_BY(cs_main);
 
@@ -134,14 +154,6 @@ public:
     bool WriteBlockIndexDB() EXCLUSIVE_LOCKS_REQUIRED(::cs_main);
     bool LoadBlockIndexDB() EXCLUSIVE_LOCKS_REQUIRED(::cs_main);
 
-    /**
-     * Load the blocktree off disk and into memory. Populate certain metadata
-     * per index entry (nStatus, nChainWork, nTimeMax, etc.) as well as peripheral
-     * collections like m_dirty_blockindex.
-     */
-    bool LoadBlockIndex(const Consensus::Params& consensus_params)
-        EXCLUSIVE_LOCKS_REQUIRED(cs_main);
-
     /** Clear all data members. */
     void Unload() EXCLUSIVE_LOCKS_REQUIRED(cs_main);
 
@@ -175,12 +187,18 @@ public:
     //! Check whether the block associated with this index entry is pruned or not.
     bool IsBlockPruned(const CBlockIndex* pblockindex) EXCLUSIVE_LOCKS_REQUIRED(::cs_main);
 
+    //! Create or update a prune lock identified by its name
+    void UpdatePruneLock(const std::string& name, const PruneLockInfo& lock_info) EXCLUSIVE_LOCKS_REQUIRED(::cs_main);
+
     ~BlockManager()
     {
         Unload();
     }
 };
 
+//! Find the first block that is not pruned
+const CBlockIndex* GetFirstStoredBlock(const CBlockIndex* start_block) EXCLUSIVE_LOCKS_REQUIRED(::cs_main);
+
 void CleanupBlockRevFiles();
 
 /** Open a block file (blk?????.dat) */