cache: support new leveldb (>=1.21) max-file-size option

requires build/install with -tags="ldbpost121"

cache/config.go

@@ -13,6 +13,7 @@ type cacheOptions struct {
 	BlockRestartInterval int
 	WriteBufferSizeM     int
 	BlockSizeK           int
+	MaxFileSizeM         int
 }
 
 type coordsCacheOptions struct {
@@ -36,6 +37,7 @@ const defaultConfig = `
         "WriteBufferSizeM": 64,
         "BlockSizeK": 0,
         "MaxOpenFiles": 64,
+        "MaxFileSizeM": 32,
         "BlockRestartInterval": 256,
         "BunchSize": 32,
         "BunchCacheCapacity": 8096
@@ -45,6 +47,7 @@ const defaultConfig = `
         "WriteBufferSizeM": 64,
         "BlockSizeK": 0,
         "MaxOpenFiles": 64,
+        "MaxFileSizeM": 32,
         "BlockRestartInterval": 128
     },
     "Ways": {
@@ -52,6 +55,7 @@ const defaultConfig = `
         "WriteBufferSizeM": 64,
         "BlockSizeK": 0,
         "MaxOpenFiles": 64,
+        "MaxFileSizeM": 32,
         "BlockRestartInterval": 128
     },
     "Relations": {
@@ -59,6 +63,7 @@ const defaultConfig = `
         "WriteBufferSizeM": 64,
         "BlockSizeK": 0,
         "MaxOpenFiles": 64,
+        "MaxFileSizeM": 32,
         "BlockRestartInterval": 128
     },
     "CoordsIndex": {
@@ -66,6 +71,7 @@ const defaultConfig = `
         "WriteBufferSizeM": 128,
         "BlockSizeK": 0,
         "MaxOpenFiles": 256,
+        "MaxFileSizeM": 8,
         "BlockRestartInterval": 256
     },
     "WaysIndex": {
@@ -73,6 +79,7 @@ const defaultConfig = `
         "WriteBufferSizeM": 64,
         "BlockSizeK": 0,
         "MaxOpenFiles": 64,
+        "MaxFileSizeM": 8,
         "BlockRestartInterval": 128
     }
 }

cache/ldb_post_121.go

@@ -0,0 +1,18 @@
+// +build ldbpost121
+
+package cache
+
+// #cgo LDFLAGS: -lleveldb
+// #include "leveldb/c.h"
+import "C"
+
+import (
+	"unsafe"
+
+	"github.com/jmhodges/levigo"
+)
+
+func setMaxFileSize(o *levigo.Options, maxFileSize int) {
+	p := (*C.struct_leveldb_options_t)(unsafe.Pointer(o.Opt))
+	C.leveldb_options_set_max_file_size(p, C.size_t(maxFileSize))
+}

cache/ldb_pre_121.go

@@ -0,0 +1,15 @@
+// +build !ldbpost121
+
+package cache
+
+// #cgo LDFLAGS: -lleveldb
+// #include "leveldb/c.h"
+import "C"
+
+import (
+	"github.com/jmhodges/levigo"
+)
+
+func setMaxFileSize(o *levigo.Options, maxFileSize int) {
+	// setMaxFileSize is only available with LevelDB 1.21 and higher.
+}

cache/osm.go

@@ -175,6 +175,11 @@ func (c *cache) open(path string) error {
 	if c.options.BlockSizeK > 0 {
 		opts.SetBlockSize(c.options.BlockSizeK * 1024)
 	}
+	if c.options.MaxFileSizeM > 0 {
+		// max file size option is only available with LevelDB 1.21 and higher
+		// build with -tags="ldppost121" to enable this option.
+		setMaxFileSize(opts, c.options.MaxFileSizeM*1024*1024)
+	}
 
 	db, err := levigo.Open(path, opts)
 	if err != nil {
@@ -183,6 +188,7 @@ func (c *cache) open(path string) error {
 	c.db = db
 	c.wo = levigo.NewWriteOptions()
 	c.ro = levigo.NewReadOptions()
+
 	return nil
 }
 
@@ -213,5 +219,4 @@ func (c *cache) Close() {
 		c.cache.Close()
 		c.cache = nil
 	}
-
 }