vendor: update bbolt to v1.3.3

glide.lock

@@ -1,5 +1,5 @@
-hash: 6dcd52f0c5d9b95aac8d2a07aea9f72746ac0432afa4192334ad141e3da2afcf
-updated: 2019-08-19T10:57:53.265557-07:00
+hash: 3fece95d13153dbb91034bd2708f8f7a39510c682dfda4c3ff691f09a61a2fc1
+updated: 2019-08-19T20:45:29.93927922-07:00
 imports:
 - name: github.com/beorn7/perks
   version: 37c8de3658fcb183f997c4e13e8337516ab753e6
@@ -8,7 +8,7 @@ imports:
 - name: github.com/bgentry/speakeasy
   version: 4aabc24848ce5fd31929f7d1e4ea74d3709c14cd
 - name: github.com/coreos/bbolt
-  version: 48ea1b39c25fc1bab3506fbc712ecbaa842c4d2d
+  version: a0458a2b35708eef59eb5f620ceb3cd1c01a824d
 - name: github.com/coreos/go-semver
   version: 8ab6407b697782a06568d4b7f1db25550ec2e4c6
   subpackages:
@@ -168,7 +168,7 @@ imports:
   - unix
   - windows
 - name: golang.org/x/text
-  version: b19bf474d317b857955b12035d2c5acb57ce8b01
+  version: 342b2e1fbaa52c93f31447ad2c6abc048c63e475
   subpackages:
   - secure/bidirule
   - transform

glide.yaml

@@ -5,7 +5,7 @@ import:
 - package: github.com/bgentry/speakeasy
   version: v0.1.0
 - package: github.com/coreos/bbolt
-  version: v1.3.1-coreos.6
+  version: v1.3.3
 - package: github.com/coreos/go-semver
   version: v0.2.0
   subpackages:

vendor/github.com/coreos/bbolt/bolt_386.go

@@ -1,4 +1,4 @@
-package bolt
+package bbolt
 
 // maxMapSize represents the largest mmap size supported by Bolt.
 const maxMapSize = 0x7FFFFFFF // 2GB

vendor/github.com/coreos/bbolt/bolt_amd64.go

@@ -1,4 +1,4 @@
-package bolt
+package bbolt
 
 // maxMapSize represents the largest mmap size supported by Bolt.
 const maxMapSize = 0xFFFFFFFFFFFF // 256TB

vendor/github.com/coreos/bbolt/bolt_arm.go

@@ -1,4 +1,4 @@
-package bolt
+package bbolt
 
 import "unsafe"
 

vendor/github.com/coreos/bbolt/bolt_arm64.go

@@ -1,6 +1,6 @@
 // +build arm64
 
-package bolt
+package bbolt
 
 // maxMapSize represents the largest mmap size supported by Bolt.
 const maxMapSize = 0xFFFFFFFFFFFF // 256TB

vendor/github.com/coreos/bbolt/bolt_linux.go

@@ -1,4 +1,4 @@
-package bolt
+package bbolt
 
 import (
 	"syscall"

vendor/github.com/coreos/bbolt/bolt_mips64x.go

@@ -1,6 +1,6 @@
 // +build mips64 mips64le
 
-package bolt
+package bbolt
 
 // maxMapSize represents the largest mmap size supported by Bolt.
 const maxMapSize = 0x8000000000 // 512GB

vendor/github.com/coreos/bbolt/bolt_mipsx.go

@@ -1,6 +1,6 @@
 // +build mips mipsle
 
-package bolt
+package bbolt
 
 // maxMapSize represents the largest mmap size supported by Bolt.
 const maxMapSize = 0x40000000 // 1GB

vendor/github.com/coreos/bbolt/bolt_openbsd.go

@@ -1,4 +1,4 @@
-package bolt
+package bbolt
 
 import (
 	"syscall"

vendor/github.com/coreos/bbolt/bolt_ppc.go

@@ -1,9 +1,12 @@
 // +build ppc
 
-package bolt
+package bbolt
 
 // maxMapSize represents the largest mmap size supported by Bolt.
 const maxMapSize = 0x7FFFFFFF // 2GB
 
 // maxAllocSize is the size used when creating array pointers.
 const maxAllocSize = 0xFFFFFFF
+
+// Are unaligned load/stores broken on this arch?
+var brokenUnaligned = false

vendor/github.com/coreos/bbolt/bolt_ppc64.go

@@ -1,6 +1,6 @@
 // +build ppc64
 
-package bolt
+package bbolt
 
 // maxMapSize represents the largest mmap size supported by Bolt.
 const maxMapSize = 0xFFFFFFFFFFFF // 256TB

vendor/github.com/coreos/bbolt/bolt_ppc64le.go

@@ -1,6 +1,6 @@
 // +build ppc64le
 
-package bolt
+package bbolt
 
 // maxMapSize represents the largest mmap size supported by Bolt.
 const maxMapSize = 0xFFFFFFFFFFFF // 256TB

vendor/github.com/coreos/bbolt/bolt_riscv64.go

@@ -0,0 +1,12 @@
+// +build riscv64
+
+package bbolt
+
+// maxMapSize represents the largest mmap size supported by Bolt.
+const maxMapSize = 0xFFFFFFFFFFFF // 256TB
+
+// maxAllocSize is the size used when creating array pointers.
+const maxAllocSize = 0x7FFFFFFF
+
+// Are unaligned load/stores broken on this arch?
+var brokenUnaligned = true

vendor/github.com/coreos/bbolt/bolt_s390x.go

@@ -1,6 +1,6 @@
 // +build s390x
 
-package bolt
+package bbolt
 
 // maxMapSize represents the largest mmap size supported by Bolt.
 const maxMapSize = 0xFFFFFFFFFFFF // 256TB

vendor/github.com/coreos/bbolt/bolt_unix.go

@@ -1,17 +1,16 @@
 // +build !windows,!plan9,!solaris
 
-package bolt
+package bbolt
 
 import (
 	"fmt"
-	"os"
 	"syscall"
 	"time"
 	"unsafe"
 )
 
 // flock acquires an advisory lock on a file descriptor.
-func flock(db *DB, mode os.FileMode, exclusive bool, timeout time.Duration) error {
+func flock(db *DB, exclusive bool, timeout time.Duration) error {
 	var t time.Time
 	if timeout != 0 {
 		t = time.Now()
@@ -56,7 +55,9 @@ func mmap(db *DB, sz int) error {
 	}
 
 	// Advise the kernel that the mmap is accessed randomly.
-	if err := madvise(b, syscall.MADV_RANDOM); err != nil {
+	err = madvise(b, syscall.MADV_RANDOM)
+	if err != nil && err != syscall.ENOSYS {
+		// Ignore not implemented error in kernel because it still works.
 		return fmt.Errorf("madvise: %s", err)
 	}
 

vendor/github.com/coreos/bbolt/bolt_unix_solaris.go

@@ -1,8 +1,7 @@
-package bolt
+package bbolt
 
 import (
 	"fmt"
-	"os"
 	"syscall"
 	"time"
 	"unsafe"
@@ -11,7 +10,7 @@ import (
 )
 
 // flock acquires an advisory lock on a file descriptor.
-func flock(db *DB, mode os.FileMode, exclusive bool, timeout time.Duration) error {
+func flock(db *DB, exclusive bool, timeout time.Duration) error {
 	var t time.Time
 	if timeout != 0 {
 		t = time.Now()

vendor/github.com/coreos/bbolt/bolt_windows.go

@@ -1,4 +1,4 @@
-package bolt
+package bbolt
 
 import (
 	"fmt"
@@ -16,8 +16,6 @@ var (
 )
 
 const (
-	lockExt = ".lock"
-
 	// see https://msdn.microsoft.com/en-us/library/windows/desktop/aa365203(v=vs.85).aspx
 	flagLockExclusive       = 2
 	flagLockFailImmediately = 1
@@ -48,28 +46,24 @@ func fdatasync(db *DB) error {
 }
 
 // flock acquires an advisory lock on a file descriptor.
-func flock(db *DB, mode os.FileMode, exclusive bool, timeout time.Duration) error {
-	// Create a separate lock file on windows because a process
-	// cannot share an exclusive lock on the same file. This is
-	// needed during Tx.WriteTo().
-	f, err := os.OpenFile(db.path+lockExt, os.O_CREATE, mode)
-	if err != nil {
-		return err
-	}
-	db.lockfile = f
-
+func flock(db *DB, exclusive bool, timeout time.Duration) error {
 	var t time.Time
 	if timeout != 0 {
 		t = time.Now()
 	}
-	fd := f.Fd()
 	var flag uint32 = flagLockFailImmediately
 	if exclusive {
 		flag |= flagLockExclusive
 	}
 	for {
-		// Attempt to obtain an exclusive lock.
-		err := lockFileEx(syscall.Handle(fd), flag, 0, 1, 0, &syscall.Overlapped{})
+		// Fix for https://github.com/etcd-io/bbolt/issues/121. Use byte-range
+		// -1..0 as the lock on the database file.
+		var m1 uint32 = (1 << 32) - 1 // -1 in a uint32
+		err := lockFileEx(syscall.Handle(db.file.Fd()), flag, 0, 1, 0, &syscall.Overlapped{
+			Offset:     m1,
+			OffsetHigh: m1,
+		})
+
 		if err == nil {
 			return nil
 		} else if err != errLockViolation {
@@ -88,9 +82,11 @@ func flock(db *DB, mode os.FileMode, exclusive bool, timeout time.Duration) erro
 
 // funlock releases an advisory lock on a file descriptor.
 func funlock(db *DB) error {
-	err := unlockFileEx(syscall.Handle(db.lockfile.Fd()), 0, 1, 0, &syscall.Overlapped{})
-	db.lockfile.Close()
-	os.Remove(db.path + lockExt)
+	var m1 uint32 = (1 << 32) - 1 // -1 in a uint32
+	err := unlockFileEx(syscall.Handle(db.file.Fd()), 0, 1, 0, &syscall.Overlapped{
+		Offset:     m1,
+		OffsetHigh: m1,
+	})
 	return err
 }
 

vendor/github.com/coreos/bbolt/boltsync_unix.go

@@ -1,6 +1,6 @@
 // +build !windows,!plan9,!linux,!openbsd
 
-package bolt
+package bbolt
 
 // fdatasync flushes written data to a file descriptor.
 func fdatasync(db *DB) error {

vendor/github.com/coreos/bbolt/bucket.go

@@ -1,4 +1,4 @@
-package bolt
+package bbolt
 
 import (
 	"bytes"

vendor/github.com/coreos/bbolt/cursor.go

@@ -1,4 +1,4 @@
-package bolt
+package bbolt
 
 import (
 	"bytes"
@@ -157,12 +157,6 @@ func (c *Cursor) seek(seek []byte) (key []byte, value []byte, flags uint32) {
 	// Start from root page/node and traverse to correct page.
 	c.stack = c.stack[:0]
 	c.search(seek, c.bucket.root)
-	ref := &c.stack[len(c.stack)-1]
-
-	// If the cursor is pointing to the end of page/node then return nil.
-	if ref.index >= ref.count() {
-		return nil, nil, 0
-	}
 
 	// If this is a bucket then return a nil value.
 	return c.keyValue()
@@ -339,6 +333,8 @@ func (c *Cursor) nsearch(key []byte) {
 // keyValue returns the key and value of the current leaf element.
 func (c *Cursor) keyValue() ([]byte, []byte, uint32) {
 	ref := &c.stack[len(c.stack)-1]
+
+	// If the cursor is pointing to the end of page/node then return nil.
 	if ref.count() == 0 || ref.index >= ref.count() {
 		return nil, nil, 0
 	}

vendor/github.com/coreos/bbolt/db.go

@@ -1,4 +1,4 @@
-package bolt
+package bbolt
 
 import (
 	"errors"
@@ -43,6 +43,16 @@ var defaultPageSize = os.Getpagesize()
 // The time elapsed between consecutive file locking attempts.
 const flockRetryTimeout = 50 * time.Millisecond
 
+// FreelistType is the type of the freelist backend
+type FreelistType string
+
+const (
+	// FreelistArrayType indicates backend freelist type is array
+	FreelistArrayType = FreelistType("array")
+	// FreelistMapType indicates backend freelist type is hashmap
+	FreelistMapType = FreelistType("hashmap")
+)
+
 // DB represents a collection of buckets persisted to a file on disk.
 // All data access is performed through transactions which can be obtained through the DB.
 // All the functions on DB will return a ErrDatabaseNotOpen if accessed before Open() is called.
@@ -70,6 +80,13 @@ type DB struct {
 	// re-sync during recovery.
 	NoFreelistSync bool
 
+	// FreelistType sets the backend freelist type. There are two options. Array which is simple but endures
+	// dramatic performance degradation if database is large and framentation in freelist is common.
+	// The alternative one is using hashmap, it is faster in almost all circumstances
+	// but it doesn't guarantee that it offers the smallest page id available. In normal case it is safe.
+	// The default type is array
+	FreelistType FreelistType
+
 	// When true, skips the truncate call when growing the database.
 	// Setting this to true is only safe on non-ext3/ext4 systems.
 	// Skipping truncation avoids preallocation of hard drive space and
@@ -104,9 +121,9 @@ type DB struct {
 	AllocSize int
 
 	path     string
+	openFile func(string, int, os.FileMode) (*os.File, error)
 	file     *os.File
-	lockfile *os.File // windows only
-	dataref  []byte   // mmap'ed readonly, write throws SEGV
+	dataref  []byte // mmap'ed readonly, write throws SEGV
 	data     *[maxMapSize]byte
 	datasz   int
 	filesz   int // current on disk file size
@@ -170,6 +187,7 @@ func Open(path string, mode os.FileMode, options *Options) (*DB, error) {
 	db.NoGrowSync = options.NoGrowSync
 	db.MmapFlags = options.MmapFlags
 	db.NoFreelistSync = options.NoFreelistSync
+	db.FreelistType = options.FreelistType
 
 	// Set default values for later DB operations.
 	db.MaxBatchSize = DefaultMaxBatchSize
@@ -182,10 +200,15 @@ func Open(path string, mode os.FileMode, options *Options) (*DB, error) {
 		db.readOnly = true
 	}
 
+	db.openFile = options.OpenFile
+	if db.openFile == nil {
+		db.openFile = os.OpenFile
+	}
+
 	// Open data file and separate sync handler for metadata writes.
 	db.path = path
 	var err error
-	if db.file, err = os.OpenFile(db.path, flag|os.O_CREATE, mode); err != nil {
+	if db.file, err = db.openFile(db.path, flag|os.O_CREATE, mode); err != nil {
 		_ = db.close()
 		return nil, err
 	}
@@ -197,8 +220,7 @@ func Open(path string, mode os.FileMode, options *Options) (*DB, error) {
 	// if !options.ReadOnly.
 	// The database file is locked using the shared lock (more than one process may
 	// hold a lock at the same time) otherwise (options.ReadOnly is set).
-	if err := flock(db, mode, !db.readOnly, options.Timeout); err != nil {
-		db.lockfile = nil // make 'unused' happy. TODO: rework locks
+	if err := flock(db, !db.readOnly, options.Timeout); err != nil {
 		_ = db.close()
 		return nil, err
 	}
@@ -213,10 +235,13 @@ func Open(path string, mode os.FileMode, options *Options) (*DB, error) {
 
 	// Initialize the database if it doesn't exist.
 	if info, err := db.file.Stat(); err != nil {
+		_ = db.close()
 		return nil, err
 	} else if info.Size() == 0 {
 		// Initialize new files with meta pages.
 		if err := db.init(); err != nil {
+			// clean up file descriptor on initialization fail
+			_ = db.close()
 			return nil, err
 		}
 	} else {
@@ -236,6 +261,7 @@ func Open(path string, mode os.FileMode, options *Options) (*DB, error) {
 				db.pageSize = int(m.pageSize)
 			}
 		} else {
+			_ = db.close()
 			return nil, ErrInvalid
 		}
 	}
@@ -281,7 +307,7 @@ func Open(path string, mode os.FileMode, options *Options) (*DB, error) {
 // concurrent accesses being made to the freelist.
 func (db *DB) loadFreelist() {
 	db.freelistLoad.Do(func() {
-		db.freelist = newFreelist()
+		db.freelist = newFreelist(db.FreelistType)
 		if !db.hasSyncedFreelist() {
 			// Reconstruct free list by scanning the DB.
 			db.freelist.readIDs(db.freepages())
@@ -289,7 +315,7 @@ func (db *DB) loadFreelist() {
 			// Read free list from freelist page.
 			db.freelist.read(db.page(db.meta().freelist))
 		}
-		db.stats.FreePageN = len(db.freelist.ids)
+		db.stats.FreePageN = db.freelist.free_count()
 	})
 }
 
@@ -441,7 +467,8 @@ func (db *DB) init() error {
 }
 
 // Close releases all database resources.
-// All transactions must be closed before closing the database.
+// It will block waiting for any open transactions to finish
+// before closing the database and returning.
 func (db *DB) Close() error {
 	db.rwlock.Lock()
 	defer db.rwlock.Unlock()
@@ -449,8 +476,8 @@ func (db *DB) Close() error {
 	db.metalock.Lock()
 	defer db.metalock.Unlock()
 
-	db.mmaplock.RLock()
-	defer db.mmaplock.RUnlock()
+	db.mmaplock.Lock()
+	defer db.mmaplock.Unlock()
 
 	return db.close()
 }
@@ -1002,6 +1029,13 @@ type Options struct {
 	// under normal operation, but requires a full database re-sync during recovery.
 	NoFreelistSync bool
 
+	// FreelistType sets the backend freelist type. There are two options. Array which is simple but endures
+	// dramatic performance degradation if database is large and framentation in freelist is common.
+	// The alternative one is using hashmap, it is faster in almost all circumstances
+	// but it doesn't guarantee that it offers the smallest page id available. In normal case it is safe.
+	// The default type is array
+	FreelistType FreelistType
+
 	// Open database in read-only mode. Uses flock(..., LOCK_SH |LOCK_NB) to
 	// grab a shared lock (UNIX).
 	ReadOnly bool
@@ -1026,13 +1060,18 @@ type Options struct {
 	// set directly on the DB itself when returned from Open(), but this option
 	// is useful in APIs which expose Options but not the underlying DB.
 	NoSync bool
+
+	// OpenFile is used to open files. It defaults to os.OpenFile. This option
+	// is useful for writing hermetic tests.
+	OpenFile func(string, int, os.FileMode) (*os.File, error)
 }
 
 // DefaultOptions represent the options used if nil options are passed into Open().
 // No timeout is used which will cause Bolt to wait indefinitely for a lock.
 var DefaultOptions = &Options{
-	Timeout:    0,
-	NoGrowSync: false,
+	Timeout:      0,
+	NoGrowSync:   false,
+	FreelistType: FreelistArrayType,
 }
 
 // Stats represents statistics about the database.

vendor/github.com/coreos/bbolt/doc.go

@@ -1,5 +1,5 @@
 /*
-Package bolt implements a low-level key/value store in pure Go. It supports
+package bbolt implements a low-level key/value store in pure Go. It supports
 fully serializable transactions, ACID semantics, and lock-free MVCC with
 multiple readers and a single writer. Bolt can be used for projects that
 want a simple data store without the need to add large dependencies such as
@@ -41,4 +41,4 @@ point to different data or can point to invalid memory which will cause a panic.
 
 
 */
-package bolt
+package bbolt

vendor/github.com/coreos/bbolt/errors.go

@@ -1,4 +1,4 @@
-package bolt
+package bbolt
 
 import "errors"
 

vendor/github.com/coreos/bbolt/freelist.go

@@ -1,4 +1,4 @@
-package bolt
+package bbolt
 
 import (
 	"fmt"
@@ -14,22 +14,54 @@ type txPending struct {
 	lastReleaseBegin txid   // beginning txid of last matching releaseRange
 }
 
+// pidSet holds the set of starting pgids which have the same span size
+type pidSet map[pgid]struct{}
+
 // freelist represents a list of all pages that are available for allocation.
 // It also tracks pages that have been freed but are still in use by open transactions.
 type freelist struct {
-	ids     []pgid              // all free and available free page ids.
-	allocs  map[pgid]txid       // mapping of txid that allocated a pgid.
-	pending map[txid]*txPending // mapping of soon-to-be free page ids by tx.
-	cache   map[pgid]bool       // fast lookup of all free and pending page ids.
+	freelistType   FreelistType                // freelist type
+	ids            []pgid                      // all free and available free page ids.
+	allocs         map[pgid]txid               // mapping of txid that allocated a pgid.
+	pending        map[txid]*txPending         // mapping of soon-to-be free page ids by tx.
+	cache          map[pgid]bool               // fast lookup of all free and pending page ids.
+	freemaps       map[uint64]pidSet           // key is the size of continuous pages(span), value is a set which contains the starting pgids of same size
+	forwardMap     map[pgid]uint64             // key is start pgid, value is its span size
+	backwardMap    map[pgid]uint64             // key is end pgid, value is its span size
+	allocate       func(txid txid, n int) pgid // the freelist allocate func
+	free_count     func() int                  // the function which gives you free page number
+	mergeSpans     func(ids pgids)             // the mergeSpan func
+	getFreePageIDs func() []pgid               // get free pgids func
+	readIDs        func(pgids []pgid)          // readIDs func reads list of pages and init the freelist
 }
 
 // newFreelist returns an empty, initialized freelist.
-func newFreelist() *freelist {
-	return &freelist{
-		allocs:  make(map[pgid]txid),
-		pending: make(map[txid]*txPending),
-		cache:   make(map[pgid]bool),
+func newFreelist(freelistType FreelistType) *freelist {
+	f := &freelist{
+		freelistType: freelistType,
+		allocs:       make(map[pgid]txid),
+		pending:      make(map[txid]*txPending),
+		cache:        make(map[pgid]bool),
+		freemaps:     make(map[uint64]pidSet),
+		forwardMap:   make(map[pgid]uint64),
+		backwardMap:  make(map[pgid]uint64),
 	}
+
+	if freelistType == FreelistMapType {
+		f.allocate = f.hashmapAllocate
+		f.free_count = f.hashmapFreeCount
+		f.mergeSpans = f.hashmapMergeSpans
+		f.getFreePageIDs = f.hashmapGetFreePageIDs
+		f.readIDs = f.hashmapReadIDs
+	} else {
+		f.allocate = f.arrayAllocate
+		f.free_count = f.arrayFreeCount
+		f.mergeSpans = f.arrayMergeSpans
+		f.getFreePageIDs = f.arrayGetFreePageIDs
+		f.readIDs = f.arrayReadIDs
+	}
+
+	return f
 }
 
 // size returns the size of the page after serialization.
@@ -47,8 +79,8 @@ func (f *freelist) count() int {
 	return f.free_count() + f.pending_count()
 }
 
-// free_count returns count of free pages
-func (f *freelist) free_count() int {
+// arrayFreeCount returns count of free pages(array version)
+func (f *freelist) arrayFreeCount() int {
 	return len(f.ids)
 }
 
@@ -69,12 +101,12 @@ func (f *freelist) copyall(dst []pgid) {
 		m = append(m, txp.ids...)
 	}
 	sort.Sort(m)
-	mergepgids(dst, f.ids, m)
+	mergepgids(dst, f.getFreePageIDs(), m)
 }
 
-// allocate returns the starting page id of a contiguous list of pages of a given size.
+// arrayAllocate returns the starting page id of a contiguous list of pages of a given size.
 // If a contiguous block cannot be found then 0 is returned.
-func (f *freelist) allocate(txid txid, n int) pgid {
+func (f *freelist) arrayAllocate(txid txid, n int) pgid {
 	if len(f.ids) == 0 {
 		return 0
 	}
@@ -160,8 +192,7 @@ func (f *freelist) release(txid txid) {
 			delete(f.pending, tid)
 		}
 	}
-	sort.Sort(m)
-	f.ids = pgids(f.ids).merge(m)
+	f.mergeSpans(m)
 }
 
 // releaseRange moves pending pages allocated within an extent [begin,end] to the free list.
@@ -194,8 +225,7 @@ func (f *freelist) releaseRange(begin, end txid) {
 			delete(f.pending, tid)
 		}
 	}
-	sort.Sort(m)
-	f.ids = pgids(f.ids).merge(m)
+	f.mergeSpans(m)
 }
 
 // rollback removes the pages from a given pending tx.
@@ -222,8 +252,7 @@ func (f *freelist) rollback(txid txid) {
 	}
 	// Remove pages from pending list and mark as free if allocated by txid.
 	delete(f.pending, txid)
-	sort.Sort(m)
-	f.ids = pgids(f.ids).merge(m)
+	f.mergeSpans(m)
 }
 
 // freed returns whether a given page is in the free list.
@@ -249,21 +278,25 @@ func (f *freelist) read(p *page) {
 		f.ids = nil
 	} else {
 		ids := ((*[maxAllocSize]pgid)(unsafe.Pointer(&p.ptr)))[idx : idx+count]
-		f.ids = make([]pgid, len(ids))
-		copy(f.ids, ids)
 
+		// copy the ids, so we don't modify on the freelist page directly
+		idsCopy := make([]pgid, count)
+		copy(idsCopy, ids)
 		// Make sure they're sorted.
-		sort.Sort(pgids(f.ids))
-	}
+		sort.Sort(pgids(idsCopy))
 
-	// Rebuild the page cache.
+		f.readIDs(idsCopy)
+	}
+}
+
+// arrayReadIDs initializes the freelist from a given list of ids.
+func (f *freelist) arrayReadIDs(ids []pgid) {
+	f.ids = ids
 	f.reindex()
 }
 
-// read initializes the freelist from a given list of ids.
-func (f *freelist) readIDs(ids []pgid) {
-	f.ids = ids
-	f.reindex()
+func (f *freelist) arrayGetFreePageIDs() []pgid {
+	return f.ids
 }
 
 // write writes the page ids onto a freelist page. All free and pending ids are
@@ -307,22 +340,42 @@ func (f *freelist) reload(p *page) {
 	// Check each page in the freelist and build a new available freelist
 	// with any pages not in the pending lists.
 	var a []pgid
-	for _, id := range f.ids {
+	for _, id := range f.getFreePageIDs() {
 		if !pcache[id] {
 			a = append(a, id)
 		}
 	}
-	f.ids = a
 
-	// Once the available list is rebuilt then rebuild the free cache so that
-	// it includes the available and pending free pages.
-	f.reindex()
+	f.readIDs(a)
+}
+
+// noSyncReload reads the freelist from pgids and filters out pending items.
+func (f *freelist) noSyncReload(pgids []pgid) {
+	// Build a cache of only pending pages.
+	pcache := make(map[pgid]bool)
+	for _, txp := range f.pending {
+		for _, pendingID := range txp.ids {
+			pcache[pendingID] = true
+		}
+	}
+
+	// Check each page in the freelist and build a new available freelist
+	// with any pages not in the pending lists.
+	var a []pgid
+	for _, id := range pgids {
+		if !pcache[id] {
+			a = append(a, id)
+		}
+	}
+
+	f.readIDs(a)
 }
 
 // reindex rebuilds the free cache based on available and pending free lists.
 func (f *freelist) reindex() {
-	f.cache = make(map[pgid]bool, len(f.ids))
-	for _, id := range f.ids {
+	ids := f.getFreePageIDs()
+	f.cache = make(map[pgid]bool, len(ids))
+	for _, id := range ids {
 		f.cache[id] = true
 	}
 	for _, txp := range f.pending {
@@ -331,3 +384,9 @@ func (f *freelist) reindex() {
 		}
 	}
 }
+
+// arrayMergeSpans try to merge list of pages(represented by pgids) with existing spans but using array
+func (f *freelist) arrayMergeSpans(ids pgids) {
+	sort.Sort(ids)
+	f.ids = pgids(f.ids).merge(ids)
+}

vendor/github.com/coreos/bbolt/freelist_hmap.go

@@ -0,0 +1,178 @@
+package bbolt
+
+import "sort"
+
+// hashmapFreeCount returns count of free pages(hashmap version)
+func (f *freelist) hashmapFreeCount() int {
+	// use the forwardmap to get the total count
+	count := 0
+	for _, size := range f.forwardMap {
+		count += int(size)
+	}
+	return count
+}
+
+// hashmapAllocate serves the same purpose as arrayAllocate, but use hashmap as backend
+func (f *freelist) hashmapAllocate(txid txid, n int) pgid {
+	if n == 0 {
+		return 0
+	}
+
+	// if we have a exact size match just return short path
+	if bm, ok := f.freemaps[uint64(n)]; ok {
+		for pid := range bm {
+			// remove the span
+			f.delSpan(pid, uint64(n))
+
+			f.allocs[pid] = txid
+
+			for i := pgid(0); i < pgid(n); i++ {
+				delete(f.cache, pid+pgid(i))
+			}
+			return pid
+		}
+	}
+
+	// lookup the map to find larger span
+	for size, bm := range f.freemaps {
+		if size < uint64(n) {
+			continue
+		}
+
+		for pid := range bm {
+			// remove the initial
+			f.delSpan(pid, uint64(size))
+
+			f.allocs[pid] = txid
+
+			remain := size - uint64(n)
+
+			// add remain span
+			f.addSpan(pid+pgid(n), remain)
+
+			for i := pgid(0); i < pgid(n); i++ {
+				delete(f.cache, pid+pgid(i))
+			}
+			return pid
+		}
+	}
+
+	return 0
+}
+
+// hashmapReadIDs reads pgids as input an initial the freelist(hashmap version)
+func (f *freelist) hashmapReadIDs(pgids []pgid) {
+	f.init(pgids)
+
+	// Rebuild the page cache.
+	f.reindex()
+}
+
+// hashmapGetFreePageIDs returns the sorted free page ids
+func (f *freelist) hashmapGetFreePageIDs() []pgid {
+	count := f.free_count()
+	if count == 0 {
+		return nil
+	}
+
+	m := make([]pgid, 0, count)
+	for start, size := range f.forwardMap {
+		for i := 0; i < int(size); i++ {
+			m = append(m, start+pgid(i))
+		}
+	}
+	sort.Sort(pgids(m))
+
+	return m
+}
+
+// hashmapMergeSpans try to merge list of pages(represented by pgids) with existing spans
+func (f *freelist) hashmapMergeSpans(ids pgids) {
+	for _, id := range ids {
+		// try to see if we can merge and update
+		f.mergeWithExistingSpan(id)
+	}
+}
+
+// mergeWithExistingSpan merges pid to the existing free spans, try to merge it backward and forward
+func (f *freelist) mergeWithExistingSpan(pid pgid) {
+	prev := pid - 1
+	next := pid + 1
+
+	preSize, mergeWithPrev := f.backwardMap[prev]
+	nextSize, mergeWithNext := f.forwardMap[next]
+	newStart := pid
+	newSize := uint64(1)
+
+	if mergeWithPrev {
+		//merge with previous span
+		start := prev + 1 - pgid(preSize)
+		f.delSpan(start, preSize)
+
+		newStart -= pgid(preSize)
+		newSize += preSize
+	}
+
+	if mergeWithNext {
+		// merge with next span
+		f.delSpan(next, nextSize)
+		newSize += nextSize
+	}
+
+	f.addSpan(newStart, newSize)
+}
+
+func (f *freelist) addSpan(start pgid, size uint64) {
+	f.backwardMap[start-1+pgid(size)] = size
+	f.forwardMap[start] = size
+	if _, ok := f.freemaps[size]; !ok {
+		f.freemaps[size] = make(map[pgid]struct{})
+	}
+
+	f.freemaps[size][start] = struct{}{}
+}
+
+func (f *freelist) delSpan(start pgid, size uint64) {
+	delete(f.forwardMap, start)
+	delete(f.backwardMap, start+pgid(size-1))
+	delete(f.freemaps[size], start)
+	if len(f.freemaps[size]) == 0 {
+		delete(f.freemaps, size)
+	}
+}
+
+// initial from pgids using when use hashmap version
+// pgids must be sorted
+func (f *freelist) init(pgids []pgid) {
+	if len(pgids) == 0 {
+		return
+	}
+
+	size := uint64(1)
+	start := pgids[0]
+
+	if !sort.SliceIsSorted([]pgid(pgids), func(i, j int) bool { return pgids[i] < pgids[j] }) {
+		panic("pgids not sorted")
+	}
+
+	f.freemaps = make(map[uint64]pidSet)
+	f.forwardMap = make(map[pgid]uint64)
+	f.backwardMap = make(map[pgid]uint64)
+
+	for i := 1; i < len(pgids); i++ {
+		// continuous page
+		if pgids[i] == pgids[i-1]+1 {
+			size++
+		} else {
+			f.addSpan(start, size)
+
+			size = 1
+			start = pgids[i]
+		}
+	}
+
+	// init the tail
+	if size != 0 && start != 0 {
+		f.addSpan(start, size)
+	}
+}

vendor/github.com/coreos/bbolt/node.go

@@ -1,4 +1,4 @@
-package bolt
+package bbolt
 
 import (
 	"bytes"

vendor/github.com/coreos/bbolt/page.go

@@ -1,4 +1,4 @@
-package bolt
+package bbolt
 
 import (
 	"fmt"

vendor/github.com/coreos/bbolt/tx.go

@@ -1,4 +1,4 @@
-package bolt
+package bbolt
 
 import (
 	"fmt"
@@ -254,17 +254,36 @@ func (tx *Tx) Rollback() error {
 	if tx.db == nil {
 		return ErrTxClosed
 	}
-	tx.rollback()
+	tx.nonPhysicalRollback()
 	return nil
 }
 
+// nonPhysicalRollback is called when user calls Rollback directly, in this case we do not need to reload the free pages from disk.
+func (tx *Tx) nonPhysicalRollback() {
+	if tx.db == nil {
+		return
+	}
+	if tx.writable {
+		tx.db.freelist.rollback(tx.meta.txid)
+	}
+	tx.close()
+}
+
+// rollback needs to reload the free pages from disk in case some system error happens like fsync error.
 func (tx *Tx) rollback() {
 	if tx.db == nil {
 		return
 	}
 	if tx.writable {
 		tx.db.freelist.rollback(tx.meta.txid)
-		tx.db.freelist.reload(tx.db.page(tx.db.meta().freelist))
+		if !tx.db.hasSyncedFreelist() {
+			// Reconstruct free page list by scanning the DB to get the whole free page list.
+			// Note: scaning the whole db is heavy if your db size is large in NoSyncFreeList mode.
+			tx.db.freelist.noSyncReload(tx.db.freepages())
+		} else {
+			// Read free page list from freelist page.
+			tx.db.freelist.reload(tx.db.page(tx.db.meta().freelist))
+		}
 	}
 	tx.close()
 }
@@ -303,7 +322,9 @@ func (tx *Tx) close() {
 }
 
 // Copy writes the entire database to a writer.
-// This function exists for backwards compatibility. Use WriteTo() instead.
+// This function exists for backwards compatibility.
+//
+// Deprecated; Use WriteTo() instead.
 func (tx *Tx) Copy(w io.Writer) error {
 	_, err := tx.WriteTo(w)
 	return err
@@ -313,7 +334,7 @@ func (tx *Tx) Copy(w io.Writer) error {
 // If err == nil then exactly tx.Size() bytes will be written into the writer.
 func (tx *Tx) WriteTo(w io.Writer) (n int64, err error) {
 	// Attempt to open reader with WriteFlag
-	f, err := os.OpenFile(tx.db.path, os.O_RDONLY|tx.WriteFlag, 0)
+	f, err := tx.db.openFile(tx.db.path, os.O_RDONLY|tx.WriteFlag, 0)
 	if err != nil {
 		return 0, err
 	}
@@ -367,7 +388,7 @@ func (tx *Tx) WriteTo(w io.Writer) (n int64, err error) {
 // A reader transaction is maintained during the copy so it is safe to continue
 // using the database while a copy is in progress.
 func (tx *Tx) CopyFile(path string, mode os.FileMode) error {
-	f, err := os.OpenFile(path, os.O_RDWR|os.O_CREATE|os.O_TRUNC, mode)
+	f, err := tx.db.openFile(path, os.O_RDWR|os.O_CREATE|os.O_TRUNC, mode)
 	if err != nil {
 		return err
 	}

vendor/golang.org/x/text/secure/bidirule/bidirule.go

@@ -155,6 +155,7 @@ func DirectionString(s string) bidi.Direction {
 		e, sz := bidi.LookupString(s[i:])
 		if sz == 0 {
 			i++
+			continue
 		}
 		c := e.Class()
 		if c == bidi.R || c == bidi.AL || c == bidi.AN {
@@ -202,13 +203,6 @@ func (t *Transformer) isRTL() bool {
 	return t.seen&isRTL != 0
 }
 
-func (t *Transformer) isFinal() bool {
-	if !t.isRTL() {
-		return true
-	}
-	return t.state == ruleLTRFinal || t.state == ruleRTLFinal || t.state == ruleInitial
-}
-
 // Reset implements transform.Transformer.
 func (t *Transformer) Reset() { *t = Transformer{} }
 

vendor/golang.org/x/text/secure/bidirule/bidirule10.0.0.go

@@ -0,0 +1,11 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build go1.10
+
+package bidirule
+
+func (t *Transformer) isFinal() bool {
+	return t.state == ruleLTRFinal || t.state == ruleRTLFinal || t.state == ruleInitial
+}

vendor/golang.org/x/text/secure/bidirule/bidirule9.0.0.go

@@ -0,0 +1,14 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !go1.10
+
+package bidirule
+
+func (t *Transformer) isFinal() bool {
+	if !t.isRTL() {
+		return true
+	}
+	return t.state == ruleLTRFinal || t.state == ruleRTLFinal || t.state == ruleInitial
+}

vendor/golang.org/x/text/transform/transform.go

@@ -78,8 +78,8 @@ type SpanningTransformer interface {
 	// considering the error err.
 	//
 	// A nil error means that all input bytes are known to be identical to the
-	// output produced by the Transformer. A nil error can be be returned
-	// regardless of whether atEOF is true. If err is nil, then then n must
+	// output produced by the Transformer. A nil error can be returned
+	// regardless of whether atEOF is true. If err is nil, then n must
 	// equal len(src); the converse is not necessarily true.
 	//
 	// ErrEndOfSpan means that the Transformer output may differ from the
@@ -493,7 +493,7 @@ func (c *chain) Transform(dst, src []byte, atEOF bool) (nDst, nSrc int, err erro
 	return dstL.n, srcL.p, err
 }
 
-// Deprecated: use runes.Remove instead.
+// Deprecated: Use runes.Remove instead.
 func RemoveFunc(f func(r rune) bool) Transformer {
 	return removeF(f)
 }

vendor/golang.org/x/text/unicode/bidi/bidi.go

@@ -6,7 +6,7 @@
 
 // Package bidi contains functionality for bidirectional text support.
 //
-// See http://www.unicode.org/reports/tr9.
+// See https://www.unicode.org/reports/tr9.
 //
 // NOTE: UNDER CONSTRUCTION. This API may change in backwards incompatible ways
 // and without notice.

vendor/golang.org/x/text/unicode/bidi/bracket.go

@@ -12,7 +12,7 @@ import (
 
 // This file contains a port of the reference implementation of the
 // Bidi Parentheses Algorithm:
-// http://www.unicode.org/Public/PROGRAMS/BidiReferenceJava/BidiPBAReference.java
+// https://www.unicode.org/Public/PROGRAMS/BidiReferenceJava/BidiPBAReference.java
 //
 // The implementation in this file covers definitions BD14-BD16 and rule N0
 // of UAX#9.
@@ -246,7 +246,7 @@ func (p *bracketPairer) getStrongTypeN0(index int) Class {
 // assuming the given embedding direction.
 //
 // It returns ON if no strong type is found. If a single strong type is found,
-// it returns this this type. Otherwise it returns the embedding direction.
+// it returns this type. Otherwise it returns the embedding direction.
 //
 // TODO: use separate type for "strong" directionality.
 func (p *bracketPairer) classifyPairContent(loc bracketPair, dirEmbed Class) Class {

vendor/golang.org/x/text/unicode/bidi/core.go

@@ -7,7 +7,7 @@ package bidi
 import "log"
 
 // This implementation is a port based on the reference implementation found at:
-// http://www.unicode.org/Public/PROGRAMS/BidiReferenceJava/
+// https://www.unicode.org/Public/PROGRAMS/BidiReferenceJava/
 //
 // described in Unicode Bidirectional Algorithm (UAX #9).
 //

vendor/golang.org/x/text/unicode/bidi/gen.go

@@ -26,7 +26,7 @@ func main() {
 }
 
 // bidiClass names and codes taken from class "bc" in
-// http://www.unicode.org/Public/8.0.0/ucd/PropertyValueAliases.txt
+// https://www.unicode.org/Public/8.0.0/ucd/PropertyValueAliases.txt
 var bidiClass = map[string]Class{
 	"AL":  AL,  // ArabicLetter
 	"AN":  AN,  // ArabicNumber
@@ -59,7 +59,7 @@ func genTables() {
 		log.Fatalf("Too many Class constants (%#x > 0x0F).", numClass)
 	}
 	w := gen.NewCodeWriter()
-	defer w.WriteGoFile(*outputFile, "bidi")
+	defer w.WriteVersionedGoFile(*outputFile, "bidi")
 
 	gen.WriteUnicodeVersion(w)
 

vendor/golang.org/x/text/unicode/bidi/gen_ranges.go

@@ -15,7 +15,7 @@ import (
 )
 
 // These tables are hand-extracted from:
-// http://www.unicode.org/Public/8.0.0/ucd/extracted/DerivedBidiClass.txt
+// https://www.unicode.org/Public/8.0.0/ucd/extracted/DerivedBidiClass.txt
 func visitDefaults(fn func(r rune, c Class)) {
 	// first write default values for ranges listed above.
 	visitRunes(fn, AL, []rune{

vendor/golang.org/x/text/unicode/bidi/tables9.0.0.go

@@ -1,5 +1,7 @@
 // Code generated by running "go generate" in golang.org/x/text. DO NOT EDIT.
 
+// +build !go1.10
+
 package bidi
 
 // UnicodeVersion is the Unicode version from which the tables in this package are derived.

vendor/golang.org/x/text/unicode/norm/composition.go

@@ -407,7 +407,7 @@ func decomposeHangul(buf []byte, r rune) int {
 
 // decomposeHangul algorithmically decomposes a Hangul rune into
 // its Jamo components.
-// See http://unicode.org/reports/tr15/#Hangul for details on decomposing Hangul.
+// See https://unicode.org/reports/tr15/#Hangul for details on decomposing Hangul.
 func (rb *reorderBuffer) decomposeHangul(r rune) {
 	r -= hangulBase
 	x := r % jamoTCount
@@ -420,7 +420,7 @@ func (rb *reorderBuffer) decomposeHangul(r rune) {
 }
 
 // combineHangul algorithmically combines Jamo character components into Hangul.
-// See http://unicode.org/reports/tr15/#Hangul for details on combining Hangul.
+// See https://unicode.org/reports/tr15/#Hangul for details on combining Hangul.
 func (rb *reorderBuffer) combineHangul(s, i, k int) {
 	b := rb.rune[:]
 	bn := rb.nrune
@@ -461,6 +461,10 @@ func (rb *reorderBuffer) combineHangul(s, i, k int) {
 // It should only be used to recompose a single segment, as it will not
 // handle alternations between Hangul and non-Hangul characters correctly.
 func (rb *reorderBuffer) compose() {
+	// Lazily load the map used by the combine func below, but do
+	// it outside of the loop.
+	recompMapOnce.Do(buildRecompMap)
+
 	// UAX #15, section X5 , including Corrigendum #5
 	// "In any character sequence beginning with starter S, a character C is
 	//  blocked from S if and only if there is some character B between S

vendor/golang.org/x/text/unicode/norm/forminfo.go

@@ -4,6 +4,8 @@
 
 package norm
 
+import "encoding/binary"
+
 // This file contains Form-specific logic and wrappers for data in tables.go.
 
 // Rune info is stored in a separate trie per composing form. A composing form
@@ -178,6 +180,17 @@ func (p Properties) TrailCCC() uint8 {
 	return ccc[p.tccc]
 }
 
+func buildRecompMap() {
+	recompMap = make(map[uint32]rune, len(recompMapPacked)/8)
+	var buf [8]byte
+	for i := 0; i < len(recompMapPacked); i += 8 {
+		copy(buf[:], recompMapPacked[i:i+8])
+		key := binary.BigEndian.Uint32(buf[:4])
+		val := binary.BigEndian.Uint32(buf[4:])
+		recompMap[key] = rune(val)
+	}
+}
+
 // Recomposition
 // We use 32-bit keys instead of 64-bit for the two codepoint keys.
 // This clips off the bits of three entries, but we know this will not
@@ -186,8 +199,14 @@ func (p Properties) TrailCCC() uint8 {
 // Note that the recomposition map for NFC and NFKC are identical.
 
 // combine returns the combined rune or 0 if it doesn't exist.
+//
+// The caller is responsible for calling
+// recompMapOnce.Do(buildRecompMap) sometime before this is called.
 func combine(a, b rune) rune {
 	key := uint32(uint16(a))<<16 + uint32(uint16(b))
+	if recompMap == nil {
+		panic("caller error") // see func comment
+	}
 	return recompMap[key]
 }
 

vendor/golang.org/x/text/unicode/norm/iter.go

@@ -128,8 +128,9 @@ func (i *Iter) Next() []byte {
 func nextASCIIBytes(i *Iter) []byte {
 	p := i.p + 1
 	if p >= i.rb.nsrc {
+		p0 := i.p
 		i.setDone()
-		return i.rb.src.bytes[i.p:p]
+		return i.rb.src.bytes[p0:p]
 	}
 	if i.rb.src.bytes[p] < utf8.RuneSelf {
 		p0 := i.p

vendor/golang.org/x/text/unicode/norm/maketables.go

@@ -12,6 +12,7 @@ package main
 
 import (
 	"bytes"
+	"encoding/binary"
 	"flag"
 	"fmt"
 	"io"
@@ -261,7 +262,7 @@ func compactCCC() {
 
 // CompositionExclusions.txt has form:
 // 0958    # ...
-// See http://unicode.org/reports/tr44/ for full explanation
+// See https://unicode.org/reports/tr44/ for full explanation
 func loadCompositionExclusions() {
 	f := gen.OpenUCDFile("CompositionExclusions.txt")
 	defer f.Close()
@@ -735,6 +736,8 @@ func makeTables() {
 			max = n
 		}
 	}
+	fmt.Fprintln(w, `import "sync"`)
+	fmt.Fprintln(w)
 
 	fmt.Fprintln(w, "const (")
 	fmt.Fprintln(w, "\t// Version is the Unicode edition from which the tables are derived.")
@@ -782,20 +785,27 @@ func makeTables() {
 		sz := nrentries * 8
 		size += sz
 		fmt.Fprintf(w, "// recompMap: %d bytes (entries only)\n", sz)
-		fmt.Fprintln(w, "var recompMap = map[uint32]rune{")
+		fmt.Fprintln(w, "var recompMap map[uint32]rune")
+		fmt.Fprintln(w, "var recompMapOnce sync.Once\n")
+		fmt.Fprintln(w, `const recompMapPacked = "" +`)
+		var buf [8]byte
 		for i, c := range chars {
 			f := c.forms[FCanonical]
 			d := f.decomp
 			if !f.isOneWay && len(d) > 0 {
 				key := uint32(uint16(d[0]))<<16 + uint32(uint16(d[1]))
-				fmt.Fprintf(w, "0x%.8X: 0x%.4X,\n", key, i)
+				binary.BigEndian.PutUint32(buf[:4], key)
+				binary.BigEndian.PutUint32(buf[4:], uint32(i))
+				fmt.Fprintf(w, "\t\t%q + // 0x%.8X: 0x%.8X\n", string(buf[:]), key, uint32(i))
 			}
 		}
-		fmt.Fprintf(w, "}\n\n")
+		// hack so we don't have to special case the trailing plus sign
+		fmt.Fprintf(w, `	""`)
+		fmt.Fprintln(w)
 	}
 
 	fmt.Fprintf(w, "// Total size of tables: %dKB (%d bytes)\n", (size+512)/1024, size)
-	gen.WriteGoFile("tables.go", "norm", w.Bytes())
+	gen.WriteVersionedGoFile("tables.go", "norm", w.Bytes())
 }
 
 func printChars() {
@@ -857,7 +867,7 @@ func verifyComputed() {
 // DerivedNormalizationProps.txt has form:
 // 00C0..00C5    ; NFD_QC; N # ...
 // 0374          ; NFD_QC; N # ...
-// See http://unicode.org/reports/tr44/ for full explanation
+// See https://unicode.org/reports/tr44/ for full explanation
 func testDerived() {
 	f := gen.OpenUCDFile("DerivedNormalizationProps.txt")
 	defer f.Close()
@@ -972,5 +982,5 @@ func printTestdata() {
 		}
 	}
 	fmt.Fprintln(w, "}")
-	gen.WriteGoFile("data_test.go", "norm", w.Bytes())
+	gen.WriteVersionedGoFile("data_test.go", "norm", w.Bytes())
 }

vendor/golang.org/x/text/unicode/norm/normalize.go

@@ -29,8 +29,8 @@ import (
 // proceed independently on both sides:
 //   f(x) == append(f(x[0:n]), f(x[n:])...)
 //
-// References: http://unicode.org/reports/tr15/ and
-// http://unicode.org/notes/tn5/.
+// References: https://unicode.org/reports/tr15/ and
+// https://unicode.org/notes/tn5/.
 type Form int
 
 const (

vendor/golang.org/x/text/unicode/norm/readwriter.go

@@ -60,8 +60,8 @@ func (w *normWriter) Close() error {
 }
 
 // Writer returns a new writer that implements Write(b)
-// by writing f(b) to w.  The returned writer may use an
-// an internal buffer to maintain state across Write calls.
+// by writing f(b) to w. The returned writer may use an
+// internal buffer to maintain state across Write calls.
 // Calling its Close method writes any buffered data to w.
 func (f Form) Writer(w io.Writer) io.WriteCloser {
 	wr := &normWriter{rb: reorderBuffer{}, w: w}

vendor/golang.org/x/text/unicode/norm/transform.go

@@ -18,7 +18,6 @@ func (Form) Reset() {}
 // Users should either catch ErrShortDst and allow dst to grow or have dst be at
 // least of size MaxTransformChunkSize to be guaranteed of progress.
 func (f Form) Transform(dst, src []byte, atEOF bool) (nDst, nSrc int, err error) {
-	n := 0
 	// Cap the maximum number of src bytes to check.
 	b := src
 	eof := atEOF
@@ -27,20 +26,21 @@ func (f Form) Transform(dst, src []byte, atEOF bool) (nDst, nSrc int, err error)
 		eof = false
 		b = b[:ns]
 	}
-	i, ok := formTable[f].quickSpan(inputBytes(b), n, len(b), eof)
-	n += copy(dst[n:], b[n:i])
+	i, ok := formTable[f].quickSpan(inputBytes(b), 0, len(b), eof)
+	n := copy(dst, b[:i])
 	if !ok {
 		nDst, nSrc, err = f.transform(dst[n:], src[n:], atEOF)
 		return nDst + n, nSrc + n, err
 	}
-	if n < len(src) && !atEOF {
+
+	if err == nil && n < len(src) && !atEOF {
 		err = transform.ErrShortSrc
 	}
 	return n, n, err
 }
 
 func flushTransform(rb *reorderBuffer) bool {
-	// Write out (must fully fit in dst, or else it is a ErrShortDst).
+	// Write out (must fully fit in dst, or else it is an ErrShortDst).
 	if len(rb.out) < rb.nrune*utf8.UTFMax {
 		return false
 	}
@@ -79,7 +79,7 @@ func (f Form) transform(dst, src []byte, atEOF bool) (nDst, nSrc int, err error)
 		nSrc += n
 		nDst += n
 		if ok {
-			if n < rb.nsrc && !atEOF {
+			if err == nil && n < rb.nsrc && !atEOF {
 				err = transform.ErrShortSrc
 			}
 			return nDst, nSrc, err