package arvados
import (
+ "errors"
+ "fmt"
"io"
"net/http"
"os"
"path"
+ "regexp"
+ "sort"
+ "strconv"
"strings"
+ "sync"
"time"
+)
+
+var (
+ ErrReadOnlyFile = errors.New("read-only file")
+ ErrNegativeOffset = errors.New("cannot seek to negative offset")
+ ErrFileExists = errors.New("file exists")
+ ErrInvalidOperation = errors.New("invalid operation")
+ ErrDirectoryNotEmpty = errors.New("directory not empty")
+ ErrPermission = os.ErrPermission
- "git.curoverse.com/arvados.git/sdk/go/manifest"
+ maxBlockSize = 1 << 26
)
type File interface {
io.Reader
+ io.Writer
io.Closer
io.Seeker
Size() int64
+ Readdir(int) ([]os.FileInfo, error)
+ Stat() (os.FileInfo, error)
+ Truncate(int64) error
}
type keepClient interface {
- ManifestFileReader(manifest.Manifest, string) (File, error)
+ ReadAt(locator string, p []byte, off int) (int, error)
+ PutB(p []byte) (string, int, error)
}
-type collectionFile struct {
- File
- collection *Collection
- name string
- size int64
+type fileinfo struct {
+ name string
+ mode os.FileMode
+ size int64
+ modTime time.Time
}
-func (cf *collectionFile) Size() int64 {
- return cf.size
+// Name implements os.FileInfo.
+func (fi fileinfo) Name() string {
+ return fi.name
}
-func (cf *collectionFile) Readdir(count int) ([]os.FileInfo, error) {
- return nil, io.EOF
+// ModTime implements os.FileInfo.
+func (fi fileinfo) ModTime() time.Time {
+ return fi.modTime
}
-func (cf *collectionFile) Stat() (os.FileInfo, error) {
- return collectionDirent{
- collection: cf.collection,
- name: cf.name,
- size: cf.size,
- isDir: false,
- }, nil
+// Mode implements os.FileInfo.
+func (fi fileinfo) Mode() os.FileMode {
+ return fi.mode
}
-type collectionDir struct {
- collection *Collection
- stream string
- dirents []os.FileInfo
+// IsDir implements os.FileInfo.
+func (fi fileinfo) IsDir() bool {
+ return fi.mode&os.ModeDir != 0
}
-// Readdir implements os.File.
-func (cd *collectionDir) Readdir(count int) ([]os.FileInfo, error) {
- ret := cd.dirents
- if count <= 0 {
- cd.dirents = nil
- return ret, nil
- } else if len(ret) == 0 {
- return nil, io.EOF
+// Size implements os.FileInfo.
+func (fi fileinfo) Size() int64 {
+ return fi.size
+}
+
+// Sys implements os.FileInfo.
+func (fi fileinfo) Sys() interface{} {
+ return nil
+}
+
+// A CollectionFileSystem is an http.Filesystem plus Stat() and
+// support for opening writable files.
+type CollectionFileSystem interface {
+ http.FileSystem
+ Stat(name string) (os.FileInfo, error)
+ Create(name string) (File, error)
+ OpenFile(name string, flag int, perm os.FileMode) (File, error)
+ Mkdir(name string, perm os.FileMode) error
+ Remove(name string) error
+ MarshalManifest(string) (string, error)
+}
+
+type fileSystem struct {
+ dirnode
+}
+
+func (fs *fileSystem) OpenFile(name string, flag int, perm os.FileMode) (File, error) {
+ return fs.dirnode.OpenFile(path.Clean(name), flag, perm)
+}
+
+func (fs *fileSystem) Open(name string) (http.File, error) {
+ return fs.dirnode.OpenFile(path.Clean(name), os.O_RDONLY, 0)
+}
+
+func (fs *fileSystem) Create(name string) (File, error) {
+ return fs.dirnode.OpenFile(path.Clean(name), os.O_CREATE|os.O_RDWR|os.O_TRUNC, 0)
+}
+
+func (fs *fileSystem) Stat(name string) (os.FileInfo, error) {
+ f, err := fs.OpenFile(name, os.O_RDONLY, 0)
+ if err != nil {
+ return nil, err
}
- var err error
- if count >= len(ret) {
- count = len(ret)
+ defer f.Close()
+ return f.Stat()
+}
+
+type inode interface {
+ Parent() inode
+ Read([]byte, filenodePtr) (int, filenodePtr, error)
+ Write([]byte, filenodePtr) (int, filenodePtr, error)
+ Truncate(int64) error
+ Readdir() []os.FileInfo
+ Size() int64
+ Stat() os.FileInfo
+ sync.Locker
+ RLock()
+ RUnlock()
+}
+
+// filenode implements inode.
+type filenode struct {
+ fileinfo fileinfo
+ parent *dirnode
+ extents []extent
+ repacked int64 // number of times anything in []extents has changed len
+ memsize int64 // bytes in memExtents
+ sync.RWMutex
+}
+
+// filenodePtr is an offset into a file that is (usually) efficient to
+// seek to. Specifically, if filenode.repacked==filenodePtr.repacked
+// then filenode.extents[filenodePtr.extentIdx][filenodePtr.extentOff]
+// corresponds to file offset filenodePtr.off. Otherwise, it is
+// necessary to reexamine len(filenode.extents[0]) etc. to find the
+// correct extent and offset.
+type filenodePtr struct {
+ off int64
+ extentIdx int
+ extentOff int
+ repacked int64
+}
+
+// seek returns a ptr that is consistent with both startPtr.off and
+// the current state of fn. The caller must already hold fn.RLock() or
+// fn.Lock().
+//
+// If startPtr points beyond the end of the file, ptr will point to
+// exactly the end of the file.
+//
+// After seeking:
+//
+// ptr.extentIdx == len(filenode.extents) // i.e., at EOF
+// ||
+// filenode.extents[ptr.extentIdx].Len() >= ptr.extentOff
+func (fn *filenode) seek(startPtr filenodePtr) (ptr filenodePtr) {
+ ptr = startPtr
+ if ptr.off < 0 {
+ // meaningless anyway
+ return
+ } else if ptr.off >= fn.fileinfo.size {
+ ptr.off = fn.fileinfo.size
+ ptr.extentIdx = len(fn.extents)
+ ptr.extentOff = 0
+ ptr.repacked = fn.repacked
+ return
+ } else if ptr.repacked == fn.repacked {
+ // extentIdx and extentOff accurately reflect ptr.off,
+ // but might have fallen off the end of an extent
+ if ptr.extentOff >= fn.extents[ptr.extentIdx].Len() {
+ ptr.extentIdx++
+ ptr.extentOff = 0
+ }
+ return
+ }
+ defer func() {
+ ptr.repacked = fn.repacked
+ }()
+ if ptr.off >= fn.fileinfo.size {
+ ptr.extentIdx, ptr.extentOff = len(fn.extents), 0
+ return
+ }
+ // Recompute extentIdx and extentOff. We have already
+ // established fn.fileinfo.size > ptr.off >= 0, so we don't
+ // have to deal with edge cases here.
+ var off int64
+ for ptr.extentIdx, ptr.extentOff = 0, 0; off < ptr.off; ptr.extentIdx++ {
+ // This would panic (index out of range) if
+ // fn.fileinfo.size were larger than
+ // sum(fn.extents[i].Len()) -- but that can't happen
+ // because we have ensured fn.fileinfo.size is always
+ // accurate.
+ extLen := int64(fn.extents[ptr.extentIdx].Len())
+ if off+extLen > ptr.off {
+ ptr.extentOff = int(ptr.off - off)
+ break
+ }
+ off += extLen
+ }
+ return
+}
+
+func (fn *filenode) appendExtent(e extent) {
+ fn.Lock()
+ defer fn.Unlock()
+ fn.extents = append(fn.extents, e)
+ fn.fileinfo.size += int64(e.Len())
+}
+
+func (fn *filenode) Parent() inode {
+ return fn.parent
+}
+
+func (fn *filenode) Readdir() []os.FileInfo {
+ return nil
+}
+
+func (fn *filenode) Read(p []byte, startPtr filenodePtr) (n int, ptr filenodePtr, err error) {
+ fn.RLock()
+ defer fn.RUnlock()
+ ptr = fn.seek(startPtr)
+ if ptr.off < 0 {
+ err = ErrNegativeOffset
+ return
+ }
+ if ptr.extentIdx >= len(fn.extents) {
err = io.EOF
+ return
+ }
+ n, err = fn.extents[ptr.extentIdx].ReadAt(p, int64(ptr.extentOff))
+ if n > 0 {
+ ptr.off += int64(n)
+ ptr.extentOff += n
+ if ptr.extentOff == fn.extents[ptr.extentIdx].Len() {
+ ptr.extentIdx++
+ ptr.extentOff = 0
+ if ptr.extentIdx < len(fn.extents) && err == io.EOF {
+ err = nil
+ }
+ }
}
- cd.dirents = cd.dirents[count:]
- return ret[:count], err
+ return
}
-// Stat implements os.File.
-func (cd *collectionDir) Stat() (os.FileInfo, error) {
- return collectionDirent{
- collection: cd.collection,
- name: path.Base(cd.stream),
- isDir: true,
- size: int64(len(cd.dirents)),
- }, nil
+func (fn *filenode) Size() int64 {
+ fn.RLock()
+ defer fn.RUnlock()
+ return fn.fileinfo.Size()
+}
+
+func (fn *filenode) Stat() os.FileInfo {
+ fn.RLock()
+ defer fn.RUnlock()
+ return fn.fileinfo
}
-// Close implements os.File.
-func (cd *collectionDir) Close() error {
+func (fn *filenode) Truncate(size int64) error {
+ fn.Lock()
+ defer fn.Unlock()
+ if size < fn.fileinfo.size {
+ ptr := fn.seek(filenodePtr{off: size, repacked: fn.repacked - 1})
+ for i := ptr.extentIdx; i < len(fn.extents); i++ {
+ if ext, ok := fn.extents[i].(*memExtent); ok {
+ fn.memsize -= int64(ext.Len())
+ }
+ }
+ if ptr.extentOff == 0 {
+ fn.extents = fn.extents[:ptr.extentIdx]
+ } else {
+ fn.extents = fn.extents[:ptr.extentIdx+1]
+ switch ext := fn.extents[ptr.extentIdx].(type) {
+ case *memExtent:
+ ext.Truncate(ptr.extentOff)
+ fn.memsize += int64(ext.Len())
+ default:
+ fn.extents[ptr.extentIdx] = ext.Slice(0, ptr.extentOff)
+ }
+ }
+ fn.fileinfo.size = size
+ fn.repacked++
+ return nil
+ }
+ for size > fn.fileinfo.size {
+ grow := size - fn.fileinfo.size
+ var e writableExtent
+ var ok bool
+ if len(fn.extents) == 0 {
+ e = &memExtent{}
+ fn.extents = append(fn.extents, e)
+ } else if e, ok = fn.extents[len(fn.extents)-1].(writableExtent); !ok || e.Len() >= maxBlockSize {
+ e = &memExtent{}
+ fn.extents = append(fn.extents, e)
+ } else {
+ fn.repacked++
+ }
+ if maxgrow := int64(maxBlockSize - e.Len()); maxgrow < grow {
+ grow = maxgrow
+ }
+ e.Truncate(e.Len() + int(grow))
+ fn.fileinfo.size += grow
+ fn.memsize += grow
+ }
return nil
}
-// Read implements os.File.
-func (cd *collectionDir) Read([]byte) (int, error) {
- return 0, nil
+func (fn *filenode) Write(p []byte, startPtr filenodePtr) (n int, ptr filenodePtr, err error) {
+ fn.Lock()
+ defer fn.Unlock()
+ ptr = fn.seek(startPtr)
+ if ptr.off < 0 {
+ err = ErrNegativeOffset
+ return
+ }
+ for len(p) > 0 && err == nil {
+ cando := p
+ if len(cando) > maxBlockSize {
+ cando = cando[:maxBlockSize]
+ }
+ // Rearrange/grow fn.extents (and shrink cando if
+ // needed) such that cando can be copied to
+ // fn.extents[ptr.extentIdx] at offset ptr.extentOff.
+ cur := ptr.extentIdx
+ prev := ptr.extentIdx - 1
+ var curWritable bool
+ if cur < len(fn.extents) {
+ _, curWritable = fn.extents[cur].(writableExtent)
+ }
+ var prevAppendable bool
+ if prev >= 0 && fn.extents[prev].Len() < maxBlockSize {
+ _, prevAppendable = fn.extents[prev].(writableExtent)
+ }
+ if ptr.extentOff > 0 && !curWritable {
+ // Split a non-writable block.
+ if max := fn.extents[cur].Len() - ptr.extentOff; max <= len(cando) {
+ // Truncate cur, and insert a new
+ // extent after it.
+ cando = cando[:max]
+ fn.extents = append(fn.extents, nil)
+ copy(fn.extents[cur+1:], fn.extents[cur:])
+ } else {
+ // Split cur into two copies, truncate
+ // the one on the left, shift the one
+ // on the right, and insert a new
+ // extent between them.
+ fn.extents = append(fn.extents, nil, nil)
+ copy(fn.extents[cur+2:], fn.extents[cur:])
+ fn.extents[cur+2] = fn.extents[cur+2].Slice(ptr.extentOff+len(cando), -1)
+ }
+ cur++
+ prev++
+ e := &memExtent{}
+ e.Truncate(len(cando))
+ fn.memsize += int64(len(cando))
+ fn.extents[cur] = e
+ fn.extents[prev] = fn.extents[prev].Slice(0, ptr.extentOff)
+ ptr.extentIdx++
+ ptr.extentOff = 0
+ fn.repacked++
+ ptr.repacked++
+ } else if curWritable {
+ if fit := int(fn.extents[cur].Len()) - ptr.extentOff; fit < len(cando) {
+ cando = cando[:fit]
+ }
+ } else {
+ if prevAppendable {
+ // Shrink cando if needed to fit in prev extent.
+ if cangrow := maxBlockSize - fn.extents[prev].Len(); cangrow < len(cando) {
+ cando = cando[:cangrow]
+ }
+ }
+
+ if cur == len(fn.extents) {
+ // ptr is at EOF, filesize is changing.
+ fn.fileinfo.size += int64(len(cando))
+ } else if el := fn.extents[cur].Len(); el <= len(cando) {
+ // cando is long enough that we won't
+ // need cur any more. shrink cando to
+ // be exactly as long as cur
+ // (otherwise we'd accidentally shift
+ // the effective position of all
+ // extents after cur).
+ cando = cando[:el]
+ copy(fn.extents[cur:], fn.extents[cur+1:])
+ fn.extents = fn.extents[:len(fn.extents)-1]
+ } else {
+ // shrink cur by the same #bytes we're growing prev
+ fn.extents[cur] = fn.extents[cur].Slice(len(cando), -1)
+ }
+
+ if prevAppendable {
+ // Grow prev.
+ ptr.extentIdx--
+ ptr.extentOff = fn.extents[prev].Len()
+ fn.extents[prev].(writableExtent).Truncate(ptr.extentOff + len(cando))
+ fn.memsize += int64(len(cando))
+ ptr.repacked++
+ fn.repacked++
+ } else {
+ // Insert an extent between prev and cur, and advance prev/cur.
+ fn.extents = append(fn.extents, nil)
+ if cur < len(fn.extents) {
+ copy(fn.extents[cur+1:], fn.extents[cur:])
+ ptr.repacked++
+ fn.repacked++
+ } else {
+ // appending a new extent does
+ // not invalidate any ptrs
+ }
+ e := &memExtent{}
+ e.Truncate(len(cando))
+ fn.memsize += int64(len(cando))
+ fn.extents[cur] = e
+ cur++
+ prev++
+ }
+ }
+
+ // Finally we can copy bytes from cando to the current extent.
+ fn.extents[ptr.extentIdx].(writableExtent).WriteAt(cando, ptr.extentOff)
+ n += len(cando)
+ p = p[len(cando):]
+
+ ptr.off += int64(len(cando))
+ ptr.extentOff += len(cando)
+ if ptr.extentOff >= maxBlockSize {
+ fn.pruneMemExtents()
+ }
+ if fn.extents[ptr.extentIdx].Len() == ptr.extentOff {
+ ptr.extentOff = 0
+ ptr.extentIdx++
+ }
+ }
+ return
}
-// Seek implements os.File.
-func (cd *collectionDir) Seek(int64, int) (int64, error) {
- return 0, nil
+// Write some data out to disk to reduce memory use. Caller must have
+// write lock.
+func (fn *filenode) pruneMemExtents() {
+ // TODO: async (don't hold Lock() while waiting for Keep)
+ // TODO: share code with (*dirnode)sync()
+ // TODO: pack/flush small blocks too, when fragmented
+ for idx, ext := range fn.extents {
+ ext, ok := ext.(*memExtent)
+ if !ok || ext.Len() < maxBlockSize {
+ continue
+ }
+ locator, _, err := fn.parent.kc.PutB(ext.buf)
+ if err != nil {
+ // TODO: stall (or return errors from)
+ // subsequent writes until flushing
+ // starts to succeed
+ continue
+ }
+ fn.memsize -= int64(ext.Len())
+ fn.extents[idx] = storedExtent{
+ kc: fn.parent.kc,
+ locator: locator,
+ size: ext.Len(),
+ offset: 0,
+ length: ext.Len(),
+ }
+ }
+}
+
+// FileSystem returns a CollectionFileSystem for the collection.
+func (c *Collection) FileSystem(client *Client, kc keepClient) (CollectionFileSystem, error) {
+ fs := &fileSystem{dirnode: dirnode{
+ client: client,
+ kc: kc,
+ fileinfo: fileinfo{name: ".", mode: os.ModeDir | 0755},
+ parent: nil,
+ inodes: make(map[string]inode),
+ }}
+ fs.dirnode.parent = &fs.dirnode
+ if err := fs.dirnode.loadManifest(c.ManifestText); err != nil {
+ return nil, err
+ }
+ return fs, nil
}
-// collectionDirent implements os.FileInfo.
-type collectionDirent struct {
- collection *Collection
- name string
- isDir bool
- mode os.FileMode
- size int64
+type file struct {
+ inode
+ ptr filenodePtr
+ append bool
+ writable bool
+ unreaddirs []os.FileInfo
}
-// Name implements os.FileInfo.
-func (e collectionDirent) Name() string {
- return e.name
+func (f *file) Read(p []byte) (n int, err error) {
+ n, f.ptr, err = f.inode.Read(p, f.ptr)
+ return
}
-// ModTime implements os.FileInfo.
-func (e collectionDirent) ModTime() time.Time {
- if e.collection.ModifiedAt == nil {
- return time.Now()
+func (f *file) Seek(off int64, whence int) (pos int64, err error) {
+ size := f.inode.Size()
+ ptr := f.ptr
+ switch whence {
+ case os.SEEK_SET:
+ ptr.off = off
+ case os.SEEK_CUR:
+ ptr.off += off
+ case os.SEEK_END:
+ ptr.off = size + off
}
- return *e.collection.ModifiedAt
+ if ptr.off < 0 {
+ return f.ptr.off, ErrNegativeOffset
+ }
+ if ptr.off > size {
+ ptr.off = size
+ }
+ if ptr.off != f.ptr.off {
+ f.ptr = ptr
+ // force filenode to recompute f.ptr fields on next
+ // use
+ f.ptr.repacked = -1
+ }
+ return f.ptr.off, nil
}
-// Mode implements os.FileInfo.
-func (e collectionDirent) Mode() os.FileMode {
- if e.isDir {
- return 0555
- } else {
- return 0444
+func (f *file) Truncate(size int64) error {
+ return f.inode.Truncate(size)
+}
+
+func (f *file) Write(p []byte) (n int, err error) {
+ if !f.writable {
+ return 0, ErrReadOnlyFile
}
+ n, f.ptr, err = f.inode.Write(p, f.ptr)
+ return
}
-// IsDir implements os.FileInfo.
-func (e collectionDirent) IsDir() bool {
- return e.isDir
+func (f *file) Readdir(count int) ([]os.FileInfo, error) {
+ if !f.inode.Stat().IsDir() {
+ return nil, ErrInvalidOperation
+ }
+ if count <= 0 {
+ return f.inode.Readdir(), nil
+ }
+ if f.unreaddirs == nil {
+ f.unreaddirs = f.inode.Readdir()
+ }
+ if len(f.unreaddirs) == 0 {
+ return nil, io.EOF
+ }
+ if count > len(f.unreaddirs) {
+ count = len(f.unreaddirs)
+ }
+ ret := f.unreaddirs[:count]
+ f.unreaddirs = f.unreaddirs[count:]
+ return ret, nil
}
-// Size implements os.FileInfo.
-func (e collectionDirent) Size() int64 {
- return e.size
+func (f *file) Stat() (os.FileInfo, error) {
+ return f.inode.Stat(), nil
}
-// Sys implements os.FileInfo.
-func (e collectionDirent) Sys() interface{} {
+func (f *file) Close() error {
+ // FIXME: flush
return nil
}
-// collectionFS implements http.FileSystem.
-type collectionFS struct {
- collection *Collection
- client *Client
- kc keepClient
+type dirnode struct {
+ fileinfo fileinfo
+ parent *dirnode
+ client *Client
+ kc keepClient
+ inodes map[string]inode
+ sync.RWMutex
}
-// FileSystem returns an http.FileSystem for the collection.
-func (c *Collection) FileSystem(client *Client, kc keepClient) http.FileSystem {
- return &collectionFS{
- collection: c,
- client: client,
- kc: kc,
+// sync flushes in-memory data (for all files in the tree rooted at
+// dn) to persistent storage. Caller must hold dn.Lock().
+func (dn *dirnode) sync() error {
+ type shortBlock struct {
+ fn *filenode
+ idx int
}
+ var pending []shortBlock
+ var pendingLen int
+
+ flush := func(sbs []shortBlock) error {
+ if len(sbs) == 0 {
+ return nil
+ }
+ block := make([]byte, 0, maxBlockSize)
+ for _, sb := range sbs {
+ block = append(block, sb.fn.extents[sb.idx].(*memExtent).buf...)
+ }
+ locator, _, err := dn.kc.PutB(block)
+ if err != nil {
+ return err
+ }
+ off := 0
+ for _, sb := range sbs {
+ data := sb.fn.extents[sb.idx].(*memExtent).buf
+ sb.fn.extents[sb.idx] = storedExtent{
+ kc: dn.kc,
+ locator: locator,
+ size: len(block),
+ offset: off,
+ length: len(data),
+ }
+ off += len(data)
+ sb.fn.memsize -= int64(len(data))
+ }
+ return nil
+ }
+
+ names := make([]string, 0, len(dn.inodes))
+ for name := range dn.inodes {
+ names = append(names, name)
+ }
+ sort.Strings(names)
+
+ for _, name := range names {
+ fn, ok := dn.inodes[name].(*filenode)
+ if !ok {
+ continue
+ }
+ fn.Lock()
+ defer fn.Unlock()
+ for idx, ext := range fn.extents {
+ ext, ok := ext.(*memExtent)
+ if !ok {
+ continue
+ }
+ if ext.Len() > maxBlockSize/2 {
+ if err := flush([]shortBlock{{fn, idx}}); err != nil {
+ return err
+ }
+ continue
+ }
+ if pendingLen+ext.Len() > maxBlockSize {
+ if err := flush(pending); err != nil {
+ return err
+ }
+ pending = nil
+ pendingLen = 0
+ }
+ pending = append(pending, shortBlock{fn, idx})
+ pendingLen += ext.Len()
+ }
+ }
+ return flush(pending)
}
-func (c *collectionFS) Open(name string) (http.File, error) {
- // Ensure name looks the way it does in a manifest.
- name = path.Clean("/" + name)
- if name == "/" || name == "./" {
- name = "."
- } else if strings.HasPrefix(name, "/") {
- name = "." + name
+func (dn *dirnode) MarshalManifest(prefix string) (string, error) {
+ dn.Lock()
+ defer dn.Unlock()
+ return dn.marshalManifest(prefix)
+}
+
+// caller must have read lock.
+func (dn *dirnode) marshalManifest(prefix string) (string, error) {
+ var streamLen int64
+ type m1segment struct {
+ name string
+ offset int64
+ length int64
+ }
+ var segments []m1segment
+ var subdirs string
+ var blocks []string
+
+ if err := dn.sync(); err != nil {
+ return "", err
+ }
+
+ names := make([]string, 0, len(dn.inodes))
+ for name, node := range dn.inodes {
+ names = append(names, name)
+ node.Lock()
+ defer node.Unlock()
}
+ sort.Strings(names)
- m := manifest.Manifest{Text: c.collection.ManifestText}
+ for _, name := range names {
+ node := dn.inodes[name]
+ switch node := node.(type) {
+ case *dirnode:
+ subdir, err := node.marshalManifest(prefix + "/" + name)
+ if err != nil {
+ return "", err
+ }
+ subdirs = subdirs + subdir
+ case *filenode:
+ if len(node.extents) == 0 {
+ segments = append(segments, m1segment{name: name})
+ break
+ }
+ for _, e := range node.extents {
+ switch e := e.(type) {
+ case storedExtent:
+ if len(blocks) > 0 && blocks[len(blocks)-1] == e.locator {
+ streamLen -= int64(e.size)
+ } else {
+ blocks = append(blocks, e.locator)
+ }
+ segments = append(segments, m1segment{
+ name: name,
+ offset: streamLen + int64(e.offset),
+ length: int64(e.length),
+ })
+ streamLen += int64(e.size)
+ default:
+ // This can't happen: we
+ // haven't unlocked since
+ // calling sync().
+ panic(fmt.Sprintf("can't marshal extent type %T", e))
+ }
+ }
+ default:
+ panic(fmt.Sprintf("can't marshal inode type %T", node))
+ }
+ }
+ var filetokens []string
+ for _, s := range segments {
+ filetokens = append(filetokens, fmt.Sprintf("%d:%d:%s", s.offset, s.length, manifestEscape(s.name)))
+ }
+ if len(filetokens) == 0 {
+ return subdirs, nil
+ } else if len(blocks) == 0 {
+ blocks = []string{"d41d8cd98f00b204e9800998ecf8427e+0"}
+ }
+ return manifestEscape(prefix) + " " + strings.Join(blocks, " ") + " " + strings.Join(filetokens, " ") + "\n" + subdirs, nil
+}
- filesizes := c.fileSizes()
+func (dn *dirnode) loadManifest(txt string) error {
+ // FIXME: faster
+ var dirname string
+ streams := strings.Split(txt, "\n")
+ if streams[len(streams)-1] != "" {
+ return fmt.Errorf("line %d: no trailing newline", len(streams))
+ }
+ for i, stream := range streams[:len(streams)-1] {
+ lineno := i + 1
+ var extents []storedExtent
+ var anyFileTokens bool
+ for i, token := range strings.Split(stream, " ") {
+ if i == 0 {
+ dirname = manifestUnescape(token)
+ continue
+ }
+ if !strings.Contains(token, ":") {
+ if anyFileTokens {
+ return fmt.Errorf("line %d: bad file segment %q", lineno, token)
+ }
+ toks := strings.SplitN(token, "+", 3)
+ if len(toks) < 2 {
+ return fmt.Errorf("line %d: bad locator %q", lineno, token)
+ }
+ length, err := strconv.ParseInt(toks[1], 10, 32)
+ if err != nil || length < 0 {
+ return fmt.Errorf("line %d: bad locator %q", lineno, token)
+ }
+ extents = append(extents, storedExtent{
+ locator: token,
+ size: int(length),
+ offset: 0,
+ length: int(length),
+ })
+ continue
+ } else if len(extents) == 0 {
+ return fmt.Errorf("line %d: bad locator %q", lineno, token)
+ }
+
+ toks := strings.Split(token, ":")
+ if len(toks) != 3 {
+ return fmt.Errorf("line %d: bad file segment %q", lineno, token)
+ }
+ anyFileTokens = true
+
+ offset, err := strconv.ParseInt(toks[0], 10, 64)
+ if err != nil || offset < 0 {
+ return fmt.Errorf("line %d: bad file segment %q", lineno, token)
+ }
+ length, err := strconv.ParseInt(toks[1], 10, 64)
+ if err != nil || length < 0 {
+ return fmt.Errorf("line %d: bad file segment %q", lineno, token)
+ }
+ name := path.Clean(dirname + "/" + manifestUnescape(toks[2]))
+ dn.makeParentDirs(name)
+ f, err := dn.OpenFile(name, os.O_CREATE|os.O_WRONLY|os.O_APPEND, 0700)
+ if err != nil {
+ return fmt.Errorf("line %d: cannot append to %q: %s", lineno, name, err)
+ }
+ if f.inode.Stat().IsDir() {
+ f.Close()
+ return fmt.Errorf("line %d: cannot append to %q: is a directory", lineno, name)
+ }
+ // Map the stream offset/range coordinates to
+ // block/offset/range coordinates and add
+ // corresponding storedExtents to the filenode
+ var pos int64
+ for _, e := range extents {
+ next := pos + int64(e.Len())
+ if next < offset {
+ pos = next
+ continue
+ }
+ if pos > offset+length {
+ break
+ }
+ var blkOff int
+ if pos < offset {
+ blkOff = int(offset - pos)
+ }
+ blkLen := e.Len() - blkOff
+ if pos+int64(blkOff+blkLen) > offset+length {
+ blkLen = int(offset + length - pos - int64(blkOff))
+ }
+ f.inode.(*filenode).appendExtent(storedExtent{
+ kc: dn.kc,
+ locator: e.locator,
+ size: e.size,
+ offset: blkOff,
+ length: blkLen,
+ })
+ pos = next
+ }
+ f.Close()
+ if pos < offset+length {
+ return fmt.Errorf("line %d: invalid segment in %d-byte stream: %q", lineno, pos, token)
+ }
+ }
+ if !anyFileTokens {
+ return fmt.Errorf("line %d: no file segments", lineno)
+ } else if len(extents) == 0 {
+ return fmt.Errorf("line %d: no locators", lineno)
+ } else if dirname == "" {
+ return fmt.Errorf("line %d: no stream name", lineno)
+ }
+ }
+ return nil
+}
- // Return a file if it exists.
- if size, ok := filesizes[name]; ok {
- reader, err := c.kc.ManifestFileReader(m, name)
+func (dn *dirnode) makeParentDirs(name string) (err error) {
+ names := strings.Split(name, "/")
+ for _, name := range names[:len(names)-1] {
+ f, err := dn.mkdir(name)
if err != nil {
- return nil, err
+ return err
+ }
+ defer f.Close()
+ var ok bool
+ dn, ok = f.inode.(*dirnode)
+ if !ok {
+ return ErrFileExists
}
- return &collectionFile{
- File: reader,
- collection: c.collection,
- name: path.Base(name),
- size: size,
- }, nil
}
+ return nil
+}
+
+func (dn *dirnode) mkdir(name string) (*file, error) {
+ return dn.OpenFile(name, os.O_CREATE|os.O_EXCL, os.ModeDir|0755)
+}
+
+func (dn *dirnode) Mkdir(name string, perm os.FileMode) error {
+ f, err := dn.mkdir(name)
+ if err != nil {
+ f.Close()
+ }
+ return err
+}
- // Return a directory if it's the root dir or there are file
- // entries below it.
- children := map[string]collectionDirent{}
- for fnm, size := range filesizes {
- if !strings.HasPrefix(fnm, name+"/") {
+func (dn *dirnode) Remove(name string) error {
+ dirname, name := path.Split(name)
+ if name == "" || name == "." || name == ".." {
+ return ErrInvalidOperation
+ }
+ dn, ok := dn.lookupPath(dirname).(*dirnode)
+ if !ok {
+ return os.ErrNotExist
+ }
+ dn.Lock()
+ defer dn.Unlock()
+ switch node := dn.inodes[name].(type) {
+ case nil:
+ return os.ErrNotExist
+ case *dirnode:
+ node.RLock()
+ defer node.RUnlock()
+ if len(node.inodes) > 0 {
+ return ErrDirectoryNotEmpty
+ }
+ }
+ delete(dn.inodes, name)
+ return nil
+}
+
+func (dn *dirnode) Parent() inode {
+ dn.RLock()
+ defer dn.RUnlock()
+ return dn.parent
+}
+
+func (dn *dirnode) Readdir() (fi []os.FileInfo) {
+ dn.RLock()
+ defer dn.RUnlock()
+ fi = make([]os.FileInfo, 0, len(dn.inodes))
+ for _, inode := range dn.inodes {
+ fi = append(fi, inode.Stat())
+ }
+ return
+}
+
+func (dn *dirnode) Read(p []byte, ptr filenodePtr) (int, filenodePtr, error) {
+ return 0, ptr, ErrInvalidOperation
+}
+
+func (dn *dirnode) Write(p []byte, ptr filenodePtr) (int, filenodePtr, error) {
+ return 0, ptr, ErrInvalidOperation
+}
+
+func (dn *dirnode) Size() int64 {
+ dn.RLock()
+ defer dn.RUnlock()
+ return dn.fileinfo.Size()
+}
+
+func (dn *dirnode) Stat() os.FileInfo {
+ dn.RLock()
+ defer dn.RUnlock()
+ return dn.fileinfo
+}
+
+func (dn *dirnode) Truncate(int64) error {
+ return ErrInvalidOperation
+}
+
+// lookupPath returns the inode for the file/directory with the given
+// name (which may contain "/" separators), along with its parent
+// node. If no such file/directory exists, the returned node is nil.
+func (dn *dirnode) lookupPath(path string) (node inode) {
+ node = dn
+ for _, name := range strings.Split(path, "/") {
+ dn, ok := node.(*dirnode)
+ if !ok {
+ return nil
+ }
+ if name == "." || name == "" {
continue
}
- isDir := false
- ent := fnm[len(name)+1:]
- if i := strings.Index(ent, "/"); i >= 0 {
- ent = ent[:i]
- isDir = true
+ if name == ".." {
+ node = node.Parent()
+ continue
}
- e := children[ent]
- e.collection = c.collection
- e.isDir = isDir
- e.name = ent
- e.size = size
- children[ent] = e
+ dn.RLock()
+ node = dn.inodes[name]
+ dn.RUnlock()
}
- if len(children) == 0 && name != "." {
+ return
+}
+
+func (dn *dirnode) OpenFile(name string, flag int, perm os.FileMode) (*file, error) {
+ dirname, name := path.Split(name)
+ dn, ok := dn.lookupPath(dirname).(*dirnode)
+ if !ok {
return nil, os.ErrNotExist
}
- dirents := make([]os.FileInfo, 0, len(children))
- for _, ent := range children {
- dirents = append(dirents, ent)
+ writeMode := flag&(os.O_RDWR|os.O_WRONLY|os.O_CREATE) != 0
+ if !writeMode {
+ // A directory can be opened via "foo/", "foo/.", or
+ // "foo/..".
+ switch name {
+ case ".", "":
+ return &file{inode: dn}, nil
+ case "..":
+ return &file{inode: dn.Parent()}, nil
+ }
+ }
+ createMode := flag&os.O_CREATE != 0
+ if createMode {
+ dn.Lock()
+ defer dn.Unlock()
+ } else {
+ dn.RLock()
+ defer dn.RUnlock()
}
- return &collectionDir{
- collection: c.collection,
- stream: name,
- dirents: dirents,
+ n, ok := dn.inodes[name]
+ if !ok {
+ if !createMode {
+ return nil, os.ErrNotExist
+ }
+ if perm.IsDir() {
+ n = &dirnode{
+ parent: dn,
+ client: dn.client,
+ kc: dn.kc,
+ fileinfo: fileinfo{
+ name: name,
+ mode: os.ModeDir | 0755,
+ },
+ }
+ } else {
+ n = &filenode{
+ parent: dn,
+ fileinfo: fileinfo{
+ name: name,
+ mode: 0755,
+ },
+ }
+ }
+ if dn.inodes == nil {
+ dn.inodes = make(map[string]inode)
+ }
+ dn.inodes[name] = n
+ dn.fileinfo.size++
+ } else if flag&os.O_EXCL != 0 {
+ return nil, ErrFileExists
+ }
+ return &file{
+ inode: n,
+ append: flag&os.O_APPEND != 0,
+ writable: flag&(os.O_WRONLY|os.O_RDWR) != 0,
}, nil
}
-// fileSizes returns a map of files that can be opened. Each key
-// starts with "./".
-func (c *collectionFS) fileSizes() map[string]int64 {
- var sizes map[string]int64
- m := manifest.Manifest{Text: c.collection.ManifestText}
- for ms := range m.StreamIter() {
- for _, fss := range ms.FileStreamSegments {
- if sizes == nil {
- sizes = map[string]int64{}
- }
- sizes[ms.StreamName+"/"+fss.Name] += int64(fss.SegLen)
+type extent interface {
+ io.ReaderAt
+ Len() int
+ // Return a new extent with a subsection of the data from this
+ // one. length<0 means length=Len()-off.
+ Slice(off int, length int) extent
+}
+
+type writableExtent interface {
+ extent
+ WriteAt(p []byte, off int)
+ Truncate(n int)
+}
+
+type memExtent struct {
+ buf []byte
+}
+
+func (me *memExtent) Len() int {
+ return len(me.buf)
+}
+
+func (me *memExtent) Slice(off, length int) extent {
+ if length < 0 {
+ length = len(me.buf) - off
+ }
+ buf := make([]byte, length)
+ copy(buf, me.buf[off:])
+ return &memExtent{buf: buf}
+}
+
+func (me *memExtent) Truncate(n int) {
+ if n > cap(me.buf) {
+ newsize := 1024
+ for newsize < n {
+ newsize = newsize << 2
+ }
+ newbuf := make([]byte, n, newsize)
+ copy(newbuf, me.buf)
+ me.buf = newbuf
+ } else {
+ // Zero unused part when shrinking, in case we grow
+ // and start using it again later.
+ for i := n; i < len(me.buf); i++ {
+ me.buf[i] = 0
+ }
+ }
+ me.buf = me.buf[:n]
+}
+
+func (me *memExtent) WriteAt(p []byte, off int) {
+ if off+len(p) > len(me.buf) {
+ panic("overflowed extent")
+ }
+ copy(me.buf[off:], p)
+}
+
+func (me *memExtent) ReadAt(p []byte, off int64) (n int, err error) {
+ if off > int64(me.Len()) {
+ err = io.EOF
+ return
+ }
+ n = copy(p, me.buf[int(off):])
+ if n < len(p) {
+ err = io.EOF
+ }
+ return
+}
+
+type storedExtent struct {
+ kc keepClient
+ locator string
+ size int
+ offset int
+ length int
+}
+
+func (se storedExtent) Len() int {
+ return se.length
+}
+
+func (se storedExtent) Slice(n, size int) extent {
+ se.offset += n
+ se.length -= n
+ if size >= 0 && se.length > size {
+ se.length = size
+ }
+ return se
+}
+
+func (se storedExtent) ReadAt(p []byte, off int64) (n int, err error) {
+ if off > int64(se.length) {
+ return 0, io.EOF
+ }
+ maxlen := se.length - int(off)
+ if len(p) > maxlen {
+ p = p[:maxlen]
+ n, err = se.kc.ReadAt(se.locator, p, int(off)+se.offset)
+ if err == nil {
+ err = io.EOF
}
+ return
}
- return sizes
+ return se.kc.ReadAt(se.locator, p, int(off)+se.offset)
+}
+
+func canonicalName(name string) string {
+ name = path.Clean("/" + name)
+ if name == "/" || name == "./" {
+ name = "."
+ } else if strings.HasPrefix(name, "/") {
+ name = "." + name
+ }
+ return name
+}
+
+var manifestEscapeSeq = regexp.MustCompile(`\\([0-9]{3}|\\)`)
+
+func manifestUnescapeFunc(seq string) string {
+ if seq == `\\` {
+ return `\`
+ }
+ i, err := strconv.ParseUint(seq[1:], 8, 8)
+ if err != nil {
+ // Invalid escape sequence: can't unescape.
+ return seq
+ }
+ return string([]byte{byte(i)})
+}
+
+func manifestUnescape(s string) string {
+ return manifestEscapeSeq.ReplaceAllStringFunc(s, manifestUnescapeFunc)
+}
+
+var manifestEscapedChar = regexp.MustCompile(`[^\.\w/]`)
+
+func manifestEscapeFunc(seq string) string {
+ return fmt.Sprintf("\\%03o", byte(seq[0]))
+}
+
+func manifestEscape(s string) string {
+ return manifestEscapedChar.ReplaceAllStringFunc(s, manifestEscapeFunc)
}