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clone windows

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This commit is contained in:
Alexander Gabriel 2026-09-06 20:15:54 +02:00
parent 20c9017d3b
commit 6405d41c20
21 changed files with 2847 additions and 24 deletions
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142
README.md
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@ -5,6 +5,17 @@ two paths on the same machine), driven from a third, passive "manager"
machine. Single static Go binary, no runtime dependencies beyond the machine. Single static Go binary, no runtime dependencies beyond the
system `ssh` client for remote endpoints. system `ssh` client for remote endpoints.
Two subcommands:
- **`sync`** — mirror one file/device onto another (the original tool; see
most of this README).
- **`clone-disk`** — clone a whole system disk: boot record + partition
table + per-filesystem data, rebuilt on the target then filled from the
source. Same manager/agent/SSH/self-deploy model as `sync`; leans on the
standard disk tools already present on a rescue system (`sfdisk`,
`ntfsclone`, `partclone.*`, `e2image`, `rsync`, …). See
[clone-disk](#clone-disk) below.
## How it works ## How it works
- You run `clonetool sync` on the **manager**. Source, destination, and - You run `clonetool sync` on the **manager**. Source, destination, and
@ -123,6 +134,137 @@ clonetool sync --source \\.\E: --dest \\.\F:
handles the final partial block itself. handles the final partial block itself.
- Device size is read with `IOCTL_DISK_GET_LENGTH_INFO`. - Device size is read with `IOCTL_DISK_GET_LENGTH_INFO`.
## clone-disk
`clonetool clone-disk --source LOC --dest LOC [options]` clones a whole
disk — the boot record, the partition table, and the contents of every
partition — by **rebuilding** the layout on the target and then filling it
from the source. Orchestrated from the manager exactly like `sync`: one
control agent per side, data straight between source and target (push, or
pull fallback), self-deploy, `--sudo` escalation.
It does not reimplement any filesystem knowledge — it calls the standard
tools a rescue system already has and just moves their bytes between the two
machines.
### What it copies
1. **Partition table.** The source agent runs `sfdisk -d` (the canonical
restorable dump for both GPT and MBR). The manager turns it into a
device-independent restore script — dropping the `device:` line and
`last-lba` so it re-sizes for the target, keeping the GPT disk GUID and
every partition GUID/PARTUUID (so existing `fstab` / BCD / GRUB
references still resolve) unless `--new-ids` is given. The target agent
feeds that to `sfdisk` and re-reads the table.
2. **Boot record / boot code.** The 440-byte MBR bootstrap on every disk,
plus — on MBR disks — the whole gap before the first partition (where
GRUB's `core.img` lives), are raw-copied through the same block-diff
engine `sync` uses, addressed as byte windows. On GPT disks the
GPT structures come from `sfdisk`/`sgdisk`; a BIOS-boot partition
(`EF02`) is always cloned raw.
3. **Partition data**, per partition, by the best available method:
- **fs-image** (default when the tool exists): stream a
filesystem-aware image — `ntfsclone` for NTFS, `partclone.<fs>` for
ext*/xfs/btrfs/f2fs/fat/exfat, `e2image` as an ext fallback. Only
used blocks move.
- **raw**: the `sync` block-diff engine over the partition's byte
window. Used for swap, unrecognised filesystems, `--raw N,…`, and
whenever no image tool is installed. Re-runs move only changed blocks.
- **file-level** (`--file-level N,…`): `mkfs` on the target + `rsync`
*(planned; not yet implemented — use `--raw` or an fs-image type)*.
### Target sizing (same rules as `sync`)
- **Target is a device:** never grown. If the source layout fits, it is
reproduced as-is and any trailing space on the target is left untouched.
If the last partition(s) overflow, `--allow-shrink` will shrink them
(filesystem then partition, from the last inward) with `ntfsresize` /
`resize2fs` — this **resizes the source filesystem in place** before
imaging, so it also needs `--yes`. Without `--allow-shrink` an
over-large source is a hard error naming the partition.
- **Target is a file:** created and truncated to just what the layout
needs (or `--image-size SIZE`). Shrinking an existing image prompts
unless `--yes`.
### NTFS / Windows partitions
- **From a Linux rescue system: fully supported.** `ntfsclone` clones
Windows NTFS partitions (incl. Win10/11) at cluster level, copying only
used clusters and preserving every NTFS feature. The volume must be
*clean* — Windows Fast Startup and hibernation leave NTFS dirty; boot
Windows once and shut down fully, or run `ntfsfix -d` first. `ntfsclone`
does not fix booting: keep the partition GUIDs (default) so the existing
BCD resolves, or run `bcdboot` from Windows recovery afterwards. This is
the same approach Clonezilla uses.
- **On Windows itself: raw / VSS only.** There is no `ntfsclone` on
Windows. `clone-disk` reads the partition table via
`IOCTL_DISK_GET_DRIVE_LAYOUT_EX`, reproduces it by raw-copying the
leading sectors (and the backup GPT), and block-clones each partition
as a byte window of `\\.\PhysicalDriveN`. With `--vss` (default) it
takes a Volume Shadow Copy of each NTFS volume first for a
crash-consistent point-in-time source. This is **not** free-space-aware
(a `$Bitmap`-driven skip may come later), and shrinking to a smaller
target is not supported when the source is native Windows — use a
target at least as large, or run the clone from a Linux rescue system
to get `ntfsclone`.
### Bootloader
By default `clone-disk` only *reproduces* boot structures and preserves
disk/partition IDs — enough for a like-for-like replacement disk to boot.
`--reinstall-bootloader` additionally mounts the cloned root (+ ESP),
bind-mounts `/dev /proc /sys`, and runs `grub-install` + `update-grub` /
`grub-mkconfig` in a chroot (Linux targets). It is best-effort and never
fails the clone. For Windows, run `bcdboot C:\Windows /s S: /f ALL` from a
recovery environment.
### Examples
```
# Whole disk to an image file (image is sized to the layout)
clonetool clone-disk --source /dev/sda --dest /srv/sda.img
# Disk to disk on another host, orchestrated from a third machine
clonetool clone-disk --source box1:/dev/nvme0n1 --dest box2:/dev/nvme0n1
# Onto a smaller SSD, shrinking the last (data) partition to fit
clonetool clone-disk --source /dev/sda --dest /dev/sdb --allow-shrink --yes
# Fresh IDs so the clone can sit next to the original
clonetool clone-disk --source /dev/sda --dest /dev/sdb --new-ids
# Force a raw block clone of a partition an image tool would otherwise handle
clonetool clone-disk --source /dev/sda --dest /dev/sdb --raw 2
```
### Tools the agents call (checked at probe time, reported if missing)
`sfdisk`, `sgdisk`, `partprobe`/`blockdev`, `blkid`, `lsblk`, `losetup`,
`ntfsclone`, `ntfsresize`, `ntfsfix`, `partclone.*`, `e2image`,
`resize2fs`, `dumpe2fs`, `e2fsck`, `mkfs.*`, `mount`/`umount`, `rsync`,
`grub-install`, `update-grub`/`grub-mkconfig`. Windows: `vssadmin` /
`wmic`, `bcdboot`, `diskpart`. A missing tool just means the affected
partitions fall back to a raw block copy (or the run stops with a clear
message if that isn't safe, e.g. a partition that must shrink).
### clone-disk options
| Flag | Default | Meaning |
|---|---|---|
| `--parts LIST` | all | Only clone these partition numbers (data only; the table still lists them all). |
| `--raw LIST` | — | Force a raw block clone for these partitions. |
| `--file-level LIST` | — | `mkfs` + `rsync` these partitions (not yet implemented). |
| `--file-level-auto` | off | Use file-level for fs types with no image cloner. |
| `--allow-shrink` | off | Permit shrinking trailing partitions to fit a smaller target (resizes the **source** fs in place; needs `--yes`). |
| `--no-shrink` | off | Never shrink; fail if the target is too small. |
| `--new-ids` | off | Randomize the GPT disk GUID / MBR signature on the target. |
| `--reinstall-bootloader` | off | Run `grub-install` / `grub-mkconfig` on the target after copy (Linux). |
| `--vss` | on | Windows source: take a Volume Shadow Copy per NTFS volume. |
| `--image-size SIZE` | auto | File target: image size (default = enough for the layout). |
`--block-size --job --yes --sudo --deploy --ssh --ssh-opt --remote-bin
--connect-timeout --manager-host` mean the same as for `sync`.
## Usage ## Usage
``` ```

46
agent.go
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@ -16,10 +16,15 @@ import (
func cmdAgent(args []string) error { func cmdAgent(args []string) error {
fs := flag.NewFlagSet("agent", flag.ContinueOnError) fs := flag.NewFlagSet("agent", flag.ContinueOnError)
role := fs.String("role", "", "control|sink|source-stream (internal)") role := fs.String("role", "", "control|sink|source-stream|fs-send|fs-recv (internal)")
path := fs.String("path", "", "path to read/write") path := fs.String("path", "", "path to read/write")
size := fs.Int64("size", 0, "total sync size in bytes") size := fs.Int64("size", 0, "total sync size in bytes")
base := fs.Int64("base", 0, "byte offset the window starts at (clone-disk boot region / offset partition)")
blockSize := fs.Int64("block-size", defaultBlockSize, "block size in bytes") blockSize := fs.Int64("block-size", defaultBlockSize, "block size in bytes")
fsType := fs.String("fs", "", "filesystem type (fs-send/fs-recv)")
fsTool := fs.String("fstool", "", "fs-image tool family (fs-send/fs-recv)")
peerDisk := fs.String("peerdisk", "", "this helper's whole-disk/image path (fs-send/fs-recv)")
shrinkTo := fs.Int64("shrink", 0, "shrink this fs to N bytes before sending (fs-send)")
if err := fs.Parse(args); err != nil { if err := fs.Parse(args); err != nil {
return err return err
} }
@ -28,11 +33,17 @@ func cmdAgent(args []string) error {
case "control": case "control":
return runControlAgent() return runControlAgent()
case "sink": case "sink":
return runSinkRole(*path, *size, *blockSize) return runSinkRole(*path, *base, *size, *blockSize)
case "source-stream": case "source-stream":
return runSourceStreamRole(*path, *size, *blockSize) return runSourceStreamRole(*path, *base, *size, *blockSize)
case "fs-send":
n, _ := strconv.Atoi(*path)
return runFSSendRole(n, *fsType, *fsTool, *peerDisk, *shrinkTo)
case "fs-recv":
n, _ := strconv.Atoi(*path)
return runFSRecvRole(n, *fsType, *fsTool, *peerDisk)
default: default:
return fmt.Errorf("agent: unknown or missing --role %q (want control|sink|source-stream)", *role) return fmt.Errorf("agent: unknown or missing --role %q", *role)
} }
} }
@ -66,7 +77,16 @@ func runControlAgent() error {
runPushDriver(m, out) runPushDriver(m, out)
case msgConnectPull: case msgConnectPull:
runPullDriver(m, out) runPullDriver(m, out)
case msgProbeDisk:
handleProbeDisk(out, m)
case msgBuildLayout:
handleBuildLayout(out, m)
case msgClonePartition:
handleClonePartition(out, m)
case msgReinstallBoot:
handleReinstallBoot(out, m)
case msgClose: case msgClose:
detachAllDisks()
_ = out.WriteJSON(CtrlMsg{Type: msgBye}) _ = out.WriteJSON(CtrlMsg{Type: msgBye})
return nil return nil
default: default:
@ -127,6 +147,7 @@ func runPushDriver(req CtrlMsg, out *FrameWriter) {
tailArgs := []string{ tailArgs := []string{
"agent", "--role", "sink", "agent", "--role", "sink",
"--path", req.PeerPath, "--path", req.PeerPath,
"--base", strconv.FormatInt(req.PeerBase, 10),
"--size", strconv.FormatInt(req.Size, 10), "--size", strconv.FormatInt(req.Size, 10),
"--block-size", strconv.FormatInt(req.BlockSize, 10), "--block-size", strconv.FormatInt(req.BlockSize, 10),
} }
@ -314,7 +335,7 @@ func pumpPush(req CtrlMsg, align int64, srcFile *os.File, fw *FrameWriter, fr *F
sendErrCh := make(chan error, 1) sendErrCh := make(chan error, 1)
go func() { go func() {
sendErrCh <- runSourceLoop(sourceLoopParams{ sendErrCh <- runSourceLoop(sourceLoopParams{
File: srcFile, Size: req.Size, BlockSize: req.BlockSize, Align: align, Hashes: hashCh, Out: fw, File: srcFile, Base: req.Base, Size: req.Size, BlockSize: req.BlockSize, Align: align, Hashes: hashCh, Out: fw,
OnSkip: func(uint64) { atomic.AddInt64(&skipped, 1); maybeProgress() }, OnSkip: func(uint64) { atomic.AddInt64(&skipped, 1); maybeProgress() },
OnSend: func(idx uint64, _ [32]byte) { OnSend: func(idx uint64, _ [32]byte) {
sem <- struct{}{} sem <- struct{}{}
@ -400,6 +421,7 @@ func runPullDriver(req CtrlMsg, out *FrameWriter) {
tailArgs := []string{ tailArgs := []string{
"agent", "--role", "source-stream", "agent", "--role", "source-stream",
"--path", req.PeerPath, "--path", req.PeerPath,
"--base", strconv.FormatInt(req.PeerBase, 10),
"--size", strconv.FormatInt(req.Size, 10), "--size", strconv.FormatInt(req.Size, 10),
"--block-size", strconv.FormatInt(req.BlockSize, 10), "--block-size", strconv.FormatInt(req.BlockSize, 10),
} }
@ -448,7 +470,7 @@ func runPullDriver(req CtrlMsg, out *FrameWriter) {
hashErrCh := make(chan error, 1) hashErrCh := make(chan error, 1)
go func() { go func() {
err := streamHashBlocks(dstFile, req.Size, req.BlockSize, align, func(bh blockHash) error { err := streamHashBlocks(dstFile, req.Base, req.Size, req.BlockSize, align, func(bh blockHash) error {
return fw.WriteFrame(frameBlockHash, encodeBlockHashFrame(bh.index, bh.hash)) return fw.WriteFrame(frameBlockHash, encodeBlockHashFrame(bh.index, bh.hash))
}, scanProgressEmitter(out)) }, scanProgressEmitter(out))
if err == nil { if err == nil {
@ -463,7 +485,7 @@ func runPullDriver(req CtrlMsg, out *FrameWriter) {
}() }()
loopErr := runDestLoop(destLoopParams{ loopErr := runDestLoop(destLoopParams{
File: dstFile, BlockSize: req.BlockSize, Align: align, In: fr, File: dstFile, Base: req.Base, BlockSize: req.BlockSize, Align: align, In: fr,
OnCtrlMsg: func(m CtrlMsg) { OnCtrlMsg: func(m CtrlMsg) {
if m.Type == msgProgress { if m.Type == msgProgress {
_ = out.WriteJSON(m) _ = out.WriteJSON(m)
@ -496,7 +518,7 @@ func runPullDriver(req CtrlMsg, out *FrameWriter) {
// destination host. Dumb write endpoint: verify+pwrite+ack per block. // destination host. Dumb write endpoint: verify+pwrite+ack per block.
// --------------------------------------------------------------------- // ---------------------------------------------------------------------
func runSinkRole(path string, size, blockSize int64) error { func runSinkRole(path string, base, size, blockSize int64) error {
out := NewFrameWriter(os.Stdout) out := NewFrameWriter(os.Stdout)
in := NewFrameReader(os.Stdin) in := NewFrameReader(os.Stdin)
@ -521,7 +543,7 @@ func runSinkRole(path string, size, blockSize int64) error {
// never race on the same region. // never race on the same region.
hashErrCh := make(chan error, 1) hashErrCh := make(chan error, 1)
go func() { go func() {
err := streamHashBlocks(f, size, blockSize, align, func(bh blockHash) error { err := streamHashBlocks(f, base, size, blockSize, align, func(bh blockHash) error {
return out.WriteFrame(frameBlockHash, encodeBlockHashFrame(bh.index, bh.hash)) return out.WriteFrame(frameBlockHash, encodeBlockHashFrame(bh.index, bh.hash))
}, scanProgressEmitter(out)) }, scanProgressEmitter(out))
if err == nil { if err == nil {
@ -533,7 +555,7 @@ func runSinkRole(path string, size, blockSize int64) error {
hashErrCh <- err hashErrCh <- err
}() }()
loopErr := runDestLoop(destLoopParams{File: f, BlockSize: blockSize, Align: align, In: in, AckOut: out}) loopErr := runDestLoop(destLoopParams{File: f, Base: base, BlockSize: blockSize, Align: align, In: in, AckOut: out})
if hashErr := <-hashErrCh; hashErr != nil { if hashErr := <-hashErrCh; hashErr != nil {
return hashErr return hashErr
} }
@ -547,7 +569,7 @@ func runSinkRole(path string, size, blockSize int64) error {
// writing straight to its own stdout. // writing straight to its own stdout.
// --------------------------------------------------------------------- // ---------------------------------------------------------------------
func runSourceStreamRole(path string, size, blockSize int64) error { func runSourceStreamRole(path string, base, size, blockSize int64) error {
out := NewFrameWriter(os.Stdout) out := NewFrameWriter(os.Stdout)
in := NewFrameReader(os.Stdin) in := NewFrameReader(os.Stdin)
@ -610,7 +632,7 @@ func runSourceStreamRole(path string, size, blockSize int64) error {
} }
loopErr := runSourceLoop(sourceLoopParams{ loopErr := runSourceLoop(sourceLoopParams{
File: f, Size: size, BlockSize: blockSize, Align: align, Hashes: hashCh, Out: out, File: f, Base: base, Size: size, BlockSize: blockSize, Align: align, Hashes: hashCh, Out: out,
OnSkip: func(uint64) { skipped++; maybeProgress() }, OnSkip: func(uint64) { skipped++; maybeProgress() },
OnSend: func(uint64, [32]byte) { copied++; maybeProgress() }, OnSend: func(uint64, [32]byte) { copied++; maybeProgress() },
}) })

375
agent_disk.go Normal file
View File

@ -0,0 +1,375 @@
package main
import (
"bufio"
"encoding/json"
"fmt"
"io"
"os"
"os/exec"
"strconv"
"strings"
)
// ----------------------------------------------------------------------------
// clone-disk agent state: loop-device / mount attachments held for the life
// of the control agent so several partition clones can reuse them.
// ----------------------------------------------------------------------------
var diskAttach = map[string]*diskAttachment{}
func attachedNode(diskPath string, num int, writable bool) (string, error) {
a := diskAttach[diskPath]
if a == nil {
var err error
a, err = attachDisk(diskPath, writable)
if err != nil {
return "", err
}
diskAttach[diskPath] = a
}
return partNode(a.blockPath, num), nil
}
func detachAllDisks() {
for k, a := range diskAttach {
if a.cleanup != nil {
a.cleanup()
}
delete(diskAttach, k)
}
}
// ----------------------------------------------------------------------------
// probe_disk
// ----------------------------------------------------------------------------
func handleProbeDisk(out *FrameWriter, m CtrlMsg) {
d, err := probeDiskLayout(m.Path)
if err != nil {
_ = out.WriteJSON(CtrlMsg{Type: msgError, Message: err.Error(), NeedPriv: isPermErr(err)})
return
}
_ = out.WriteJSON(CtrlMsg{Type: msgProbeDiskOK, LayoutJSON: d.JSON()})
}
// ----------------------------------------------------------------------------
// build_layout: create/size an image, write the partition table, re-read it.
// The boot-region bytes and the partition data are moved afterwards by the
// manager through ordinary push/pull transfers.
// ----------------------------------------------------------------------------
type buildOpts struct {
Script string `json:"script"` // sfdisk restore script (Linux)
IsFile bool `json:"isFile"` // target is a regular file, not a device
ImageSize int64 `json:"imageSize"` // truncate the file to this many bytes first
}
func handleBuildLayout(out *FrameWriter, m CtrlMsg) {
var o buildOpts
if err := json.Unmarshal([]byte(m.Options), &o); err != nil {
_ = out.WriteJSON(CtrlMsg{Type: msgError, Message: "decode build opts: " + err.Error()})
return
}
if o.IsFile {
f, err := os.OpenFile(m.Path, os.O_CREATE|os.O_RDWR, 0644)
if err != nil {
_ = out.WriteJSON(CtrlMsg{Type: msgError, Message: err.Error(), NeedPriv: isPermErr(err)})
return
}
if err := f.Truncate(o.ImageSize); err != nil {
f.Close()
_ = out.WriteJSON(CtrlMsg{Type: msgError, Message: fmt.Sprintf("truncate %s: %v", m.Path, err)})
return
}
f.Close()
}
if strings.TrimSpace(o.Script) != "" {
if err := applyPartitionTable(m.Path, o.Script); err != nil {
_ = out.WriteJSON(CtrlMsg{Type: msgError, Message: err.Error(), NeedPriv: isPermErr(err)})
return
}
} else {
rereadPartTable(m.Path)
}
_ = out.WriteJSON(CtrlMsg{Type: msgBuildLayoutOK})
}
// ----------------------------------------------------------------------------
// clone_partition: fs-image and file-level methods. (Raw partitions and boot
// regions go through connect_push / connect_pull instead.)
//
// The message is sent to the SOURCE control agent first (Method set, peer
// fields as for connect_push). On a push failure the manager re-sends it to
// the DEST control agent with m.Reason == "pull".
// ----------------------------------------------------------------------------
func handleClonePartition(out *FrameWriter, m CtrlMsg) {
o, err := decodeFSCloneOpts(m.Options)
if err != nil {
_ = out.WriteJSON(CtrlMsg{Type: msgError, Message: "decode clone opts: " + err.Error()})
return
}
switch m.Method {
case "fs-image":
if m.Reason == "pull" {
runFSPullDriver(m, o, out)
} else {
runFSPushDriver(m, o, out)
}
case "file-level":
runFileLevelDriver(m, o, out)
default:
_ = out.WriteJSON(CtrlMsg{Type: msgError, Message: "unknown clone method " + m.Method})
}
}
// localDevice resolves this side's partition node. m.Path is the whole disk
// (or image); m.PartIndex is the 1-based partition number.
func localDevice(diskPath string, num int, writable bool) (string, error) {
if isDevicePath(diskPath) || looksLikeBlockDevice(diskPath) {
// real disk: node is derived directly, no attach needed
return partNode(diskPath, num), nil
}
return attachedNode(diskPath, num, writable)
}
func looksLikeBlockDevice(p string) bool {
fi, err := os.Stat(p)
return err == nil && fi.Mode()&os.ModeDevice != 0
}
// runFSPushDriver runs in the SOURCE agent: spawn the peer fs-recv (ssh or
// local), run the save tool locally, pipe save-stdout -> peer-stdin.
func runFSPushDriver(m CtrlMsg, o fsCloneOpts, out *FrameWriter) {
dev, err := localDevice(m.Path, m.PartIndex, false)
if err != nil {
_ = out.WriteJSON(CtrlMsg{Type: msgPushFailed, Reason: "source device: " + err.Error()})
return
}
cl := pickCloner(dev, o.FSType, o.Tool)
if cl == nil {
_ = out.WriteJSON(CtrlMsg{Type: msgError, Message: "no fs-image cloner for " + o.FSType})
return
}
if o.ShrinkToBytes > 0 {
_ = out.WriteJSON(CtrlMsg{Type: msgProgress, Stage: "shrink source " + o.FSType + " p" + strconv.Itoa(m.PartIndex)})
if err := preShrinkFS(dev, o.FSType, o.ShrinkToBytes); err != nil {
_ = out.WriteJSON(CtrlMsg{Type: msgError, Message: "pre-shrink: " + err.Error()})
return
}
}
peerTail := []string{"agent", "--role", "fs-recv",
"--path", strconv.Itoa(m.PartIndex), // partition number; peer resolves its own node
"--fs", o.FSType, "--fstool", o.Tool,
"--size", strconv.FormatInt(o.SizeBytes, 10),
"--peerdisk", m.PeerPath,
}
peer := peerAgentCommand(m, peerTail)
peerIn, err := peer.StdinPipe()
if err != nil {
_ = out.WriteJSON(CtrlMsg{Type: msgPushFailed, Reason: err.Error()})
return
}
peerOut, _ := peer.StdoutPipe()
peerErr := newLimitedBuffer(8192)
peer.Stderr = peerErr
if err := peer.Start(); err != nil {
_ = out.WriteJSON(CtrlMsg{Type: msgPushFailed, Reason: "start peer: " + err.Error()})
return
}
save := exec.Command(cl.save[0], cl.save[1:]...)
save.Stdout = peerIn
saveErr, _ := save.StderrPipe()
if err := save.Start(); err != nil {
_ = peer.Process.Kill()
_ = out.WriteJSON(CtrlMsg{Type: msgError, Message: fmt.Sprintf("start %s: %v", cl.save[0], err)})
return
}
var moved int64
go scanCloneProgress(saveErr, o.SizeBytes, func(b int64) {
moved = b
_ = out.WriteJSON(CtrlMsg{Type: msgProgress, Stage: o.FSType + " p" + strconv.Itoa(m.PartIndex),
BytesCopied: b, BytesTotal: o.SizeBytes, PartIndex: m.PartIndex})
})
saveWait := make(chan error, 1)
go func() { saveWait <- save.Wait() }()
sErr := <-saveWait
_ = peerIn.Close()
peerLine := readLine(peerOut)
pErr := peer.Wait()
if sErr != nil {
_ = out.WriteJSON(CtrlMsg{Type: msgError, Message: fmt.Sprintf("%s: %v", cl.save[0], sErr)})
return
}
if pErr != nil || !strings.HasPrefix(peerLine, "OK") {
reason := strings.TrimSpace(peerLine + " " + peerErr.String())
if moved == 0 {
_ = out.WriteJSON(CtrlMsg{Type: msgPushFailed, Reason: reason})
return
}
_ = out.WriteJSON(CtrlMsg{Type: msgError, Message: "peer restore failed: " + reason})
return
}
_ = out.WriteJSON(CtrlMsg{Type: msgProgress, BytesCopied: o.SizeBytes, BytesTotal: o.SizeBytes, PartIndex: m.PartIndex})
_ = out.WriteJSON(CtrlMsg{Type: msgPushOK})
}
// runFSPullDriver runs in the DEST agent: spawn the peer fs-send, run the
// restore tool locally, pipe peer-stdout -> restore-stdin.
func runFSPullDriver(m CtrlMsg, o fsCloneOpts, out *FrameWriter) {
dev, err := localDevice(m.Path, m.PartIndex, true)
if err != nil {
_ = out.WriteJSON(CtrlMsg{Type: msgPullFailed, Reason: "dest device: " + err.Error()})
return
}
cl := pickCloner(dev, o.FSType, o.Tool)
if cl == nil {
_ = out.WriteJSON(CtrlMsg{Type: msgError, Message: "no fs-image cloner for " + o.FSType})
return
}
peerTail := []string{"agent", "--role", "fs-send",
"--path", strconv.Itoa(m.PartIndex),
"--fs", o.FSType, "--fstool", o.Tool,
"--peerdisk", m.PeerPath,
"--shrink", strconv.FormatInt(o.ShrinkToBytes, 10),
}
peer := peerAgentCommand(m, peerTail)
peerOut, err := peer.StdoutPipe()
if err != nil {
_ = out.WriteJSON(CtrlMsg{Type: msgPullFailed, Reason: err.Error()})
return
}
peerErr := newLimitedBuffer(8192)
peer.Stderr = peerErr
if err := peer.Start(); err != nil {
_ = out.WriteJSON(CtrlMsg{Type: msgPullFailed, Reason: "start peer: " + err.Error()})
return
}
restore := exec.Command(cl.restore[0], cl.restore[1:]...)
restore.Stdin = peerOut
restoreErr, _ := restore.StderrPipe()
if err := restore.Start(); err != nil {
_ = peer.Process.Kill()
_ = out.WriteJSON(CtrlMsg{Type: msgError, Message: fmt.Sprintf("start %s: %v", cl.restore[0], err)})
return
}
go scanCloneProgress(restoreErr, o.SizeBytes, func(b int64) {
_ = out.WriteJSON(CtrlMsg{Type: msgProgress, Stage: o.FSType + " p" + strconv.Itoa(m.PartIndex),
BytesCopied: b, BytesTotal: o.SizeBytes, PartIndex: m.PartIndex})
})
rErr := restore.Wait()
pErr := peer.Wait()
if pErr != nil {
if rErr != nil {
_ = out.WriteJSON(CtrlMsg{Type: msgPullFailed, Reason: strings.TrimSpace(peerErr.String())})
return
}
}
if rErr != nil {
_ = out.WriteJSON(CtrlMsg{Type: msgError, Message: fmt.Sprintf("%s: %v", cl.restore[0], rErr)})
return
}
_ = out.WriteJSON(CtrlMsg{Type: msgProgress, BytesCopied: o.SizeBytes, BytesTotal: o.SizeBytes, PartIndex: m.PartIndex})
_ = out.WriteJSON(CtrlMsg{Type: msgPullOK})
}
// ----------------------------------------------------------------------------
// fs-send / fs-recv: one-shot stdio helpers spawned on the peer.
// ----------------------------------------------------------------------------
func runFSSendRole(partNum int, fsType, tool, peerDisk string, shrinkTo int64) error {
dev, err := resolveHelperDevice(peerDisk, partNum, shrinkTo > 0)
if err != nil {
return err
}
cl := pickCloner(dev, fsType, tool)
if cl == nil {
return fmt.Errorf("no fs-image cloner for %s", fsType)
}
if shrinkTo > 0 {
if err := preShrinkFS(dev, fsType, shrinkTo); err != nil {
return fmt.Errorf("pre-shrink: %w", err)
}
}
cmd := exec.Command(cl.save[0], cl.save[1:]...)
cmd.Stdout = os.Stdout
cmd.Stderr = os.Stderr
return cmd.Run()
}
func runFSRecvRole(partNum int, fsType, tool, peerDisk string) error {
dev, err := resolveHelperDevice(peerDisk, partNum, true)
if err != nil {
fmt.Fprintf(os.Stderr, "ERR: %v\n", err)
return err
}
cl := pickCloner(dev, fsType, tool)
if cl == nil {
err := fmt.Errorf("no fs-image cloner for %s", fsType)
fmt.Fprintf(os.Stdout, "ERR: %v\n", err)
return err
}
cmd := exec.Command(cl.restore[0], cl.restore[1:]...)
cmd.Stdin = os.Stdin
cmd.Stderr = os.Stderr
if err := cmd.Run(); err != nil {
fmt.Fprintf(os.Stdout, "ERR: %v\n", err)
return err
}
fmt.Fprintln(os.Stdout, "OK")
return nil
}
// resolveHelperDevice is used by the one-shot fs-send/fs-recv helpers, which
// have no persistent attachment map of their own.
func resolveHelperDevice(disk string, num int, writable bool) (string, error) {
if isDevicePath(disk) || looksLikeBlockDevice(disk) {
return partNode(disk, num), nil
}
a, err := attachDisk(disk, writable)
if err != nil {
return "", err
}
// deliberately leak the loop device until process exit; a one-shot
// helper is short-lived and the parent detaches on the control side.
_ = a
return partNode(a.blockPath, num), nil
}
// ----------------------------------------------------------------------------
// file-level: mkfs on the target partition + rsync the tree across.
// ----------------------------------------------------------------------------
func runFileLevelDriver(m CtrlMsg, o fsCloneOpts, out *FrameWriter) {
_ = out.WriteJSON(CtrlMsg{Type: msgError,
Message: "file-level clone (--file-level) is not implemented yet; use --raw or an fs-image type"})
}
// ----------------------------------------------------------------------------
// reinstall_boot: best-effort, never fatal to the clone.
// ----------------------------------------------------------------------------
func handleReinstallBoot(out *FrameWriter, m CtrlMsg) {
msg := reinstallBootloader(m.Path, m.Options)
_ = out.WriteJSON(CtrlMsg{Type: msgReinstallBootOK, Message: msg})
}
// readLine reads one \n-terminated line (used for the fs-recv status line).
func readLine(r io.Reader) string {
if r == nil {
return ""
}
br := bufio.NewReader(r)
s, _ := br.ReadString('\n')
return strings.TrimSpace(s)
}

84
boot_linux.go Normal file
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@ -0,0 +1,84 @@
//go:build linux
package main
import (
"encoding/json"
"fmt"
"os"
"os/exec"
"strings"
)
// reinstallBootloader mounts the freshly cloned root (and ESP), bind-mounts
// the API filesystems, and runs grub-install + grub-mkconfig inside a chroot.
// It is best-effort: it returns a human summary and never a hard error, so a
// clone still completes even when boot repair cannot.
func reinstallBootloader(diskPath, optsJSON string) string {
var o bootOpts
if err := json.Unmarshal([]byte(optsJSON), &o); err != nil {
return "skipped: bad boot opts: " + err.Error()
}
if o.RootPart == 0 {
return "skipped: no root partition identified (pass --reinstall-bootloader only for a Linux system disk)"
}
att, err := attachDisk(diskPath, true)
if err != nil {
return "skipped: attach: " + err.Error()
}
defer att.cleanup()
rootNode := partNode(att.blockPath, o.RootPart)
root, umount, err := mountAt(rootNode, false)
if err != nil {
return "skipped: mount root: " + err.Error()
}
defer umount()
if o.ESPPart != 0 {
espNode := partNode(att.blockPath, o.ESPPart)
espDir := root + "/boot/efi"
_ = os.MkdirAll(espDir, 0755)
if out, err := exec.Command("mount", espNode, espDir).CombinedOutput(); err != nil {
return "skipped: mount ESP: " + strings.TrimSpace(string(out))
}
defer exec.Command("umount", espDir).Run()
}
var log strings.Builder
for _, d := range []string{"dev", "proc", "sys", "run"} {
_ = exec.Command("mount", "--bind", "/"+d, root+"/"+d).Run()
defer exec.Command("umount", "-l", root+"/"+d).Run()
}
grubTarget := att.blockPath
if isDevicePath(diskPath) || looksLikeBlockDevice(diskPath) {
grubTarget = diskPath
}
giArgs := []string{root, "grub-install", "--recheck"}
if o.UEFI {
giArgs = append(giArgs, "--target=x86_64-efi", "--efi-directory=/boot/efi", "--removable")
} else {
giArgs = append(giArgs, grubTarget)
}
if out, err := exec.Command("chroot", giArgs...).CombinedOutput(); err != nil {
fmt.Fprintf(&log, "grub-install failed: %s; ", strings.TrimSpace(string(out)))
} else {
log.WriteString("grub-install ok; ")
}
mkcfg := "grub-mkconfig"
if _, err := exec.LookPath("update-grub"); err == nil {
mkcfg = "update-grub"
}
args := []string{root, mkcfg}
if mkcfg == "grub-mkconfig" {
args = append(args, "-o", "/boot/grub/grub.cfg")
}
if out, err := exec.Command("chroot", args...).CombinedOutput(); err != nil {
fmt.Fprintf(&log, "%s failed: %s", mkcfg, strings.TrimSpace(string(out)))
} else {
log.WriteString(mkcfg + " ok")
}
return log.String()
}

13
boot_other.go Normal file
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@ -0,0 +1,13 @@
//go:build !linux
package main
// reinstallBootloader is Linux-only for now. On Windows the recommended path
// is to preserve the disk signature / partition GUIDs (clone-disk does this by
// raw-copying the leading sectors) so the existing BCD store still resolves,
// and otherwise run `bcdboot W:\Windows /s S: /f ALL` from a WinPE/recovery
// environment by hand.
func reinstallBootloader(diskPath, optsJSON string) string {
return "skipped: --reinstall-bootloader is only implemented on Linux; " +
"run bcdboot from Windows recovery, or grub-install from a Linux rescue system"
}

261
clonedisk.go Normal file
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@ -0,0 +1,261 @@
package main
import (
"encoding/json"
"errors"
"fmt"
"os"
"sort"
"strings"
)
// CloneDiskConfig is everything `clonetool clone-disk` needs. It embeds
// SyncConfig for the transport/deploy/ssh knobs shared with `sync`.
type CloneDiskConfig struct {
SyncConfig
Parts []int
Raw []int
FileLevel []int
FileAuto bool
AllowShrink bool
NoShrink bool
NewIDs bool
ReinstallBoot bool
VSS bool
ImageSize int64
}
func runCloneDisk(cfg CloneDiskConfig) error {
srcSpec, err := parseSpec(cfg.Source)
if err != nil {
return fmt.Errorf("--source: %w", err)
}
dstSpec, err := parseSpec(cfg.Dest)
if err != nil {
return fmt.Errorf("--dest: %w", err)
}
if err := checkNotSame(srcSpec, dstSpec); err != nil {
return err
}
srcRemoteBin, dstRemoteBin := cfg.RemoteBin, cfg.RemoteBin
if !srcSpec.IsLocal() {
if srcRemoteBin, err = resolveRemoteBin(&cfg.SyncConfig, srcSpec, "source"); err != nil {
return err
}
}
if !dstSpec.IsLocal() {
if !srcSpec.IsLocal() && sameHost(srcSpec, dstSpec) {
dstRemoteBin = srcRemoteBin
} else if dstRemoteBin, err = resolveRemoteBin(&cfg.SyncConfig, dstSpec, "dest"); err != nil {
return err
}
}
// --- bring up both control agents -------------------------------------
srcCtrl, srcLayout, srcSudo, err := bringUpProbe(srcSpec, "source", &cfg.SyncConfig, srcRemoteBin)
if err != nil {
return fmt.Errorf("source: %w", err)
}
defer srcCtrl.Close()
dstCtrl, dstInfo, dstSudo, err := bringUpController(dstSpec, "dest", &cfg.SyncConfig, dstRemoteBin, dstSpec.Path)
if err != nil {
return fmt.Errorf("dest: %w", err)
}
defer dstCtrl.Close()
isFile := !(dstInfo.Exists && dstInfo.IsDevice)
destSize := dstInfo.Size
fmt.Fprintf(os.Stderr, "source %s: %s, %s, %d partitions\n",
srcSpec, srcLayout.Scheme, humanBytes(srcLayout.DiskSize), len(srcLayout.Partitions))
reportMissingTools(srcLayout)
// --- plan the target -------------------------------------------------
plan, err := planTargetLayout(srcLayout, isFile, destSize, planOpts{
Parts: intSet(cfg.Parts),
Raw: intSet(cfg.Raw),
FileLevel: intSet(cfg.FileLevel),
FileAuto: cfg.FileAuto,
AllowShrink: cfg.AllowShrink && !cfg.NoShrink,
NewIDs: cfg.NewIDs,
ImageSize: cfg.ImageSize,
})
if err != nil {
return err
}
for _, n := range plan.Notes {
fmt.Fprintf(os.Stderr, " %s\n", n)
}
shrinks := false
for _, pp := range plan.Parts {
if pp.ShrinkToB > 0 {
shrinks = true
}
}
if shrinks && !cfg.Yes {
return fmt.Errorf("shrinking resizes the SOURCE filesystem(s) in place before imaging; " +
"re-run with --yes to confirm, or use a larger target")
}
if isFile && !cfg.Yes && dstInfo.Exists && dstInfo.Size > plan.ImageSize {
if !confirmShrink(dstSpec, dstInfo.Size, plan.ImageSize) {
return fmt.Errorf("aborted")
}
}
// --- rebuild the partition table on the target ---------------------
bo := buildOpts{Script: plan.Script, IsFile: isFile, ImageSize: plan.ImageSize}
boJSON, _ := json.Marshal(bo)
fmt.Fprintf(os.Stderr, "rebuilding partition table on %s ...\n", dstSpec)
if err := dstCtrl.BuildLayout(dstSpec.Path, string(boJSON)); err != nil {
return fmt.Errorf("build layout: %w", err)
}
bothLocal := srcSpec.IsLocal() && dstSpec.IsLocal()
srcHost, srcUser := resolveConnectHost(srcSpec, &cfg.SyncConfig)
dstHost, dstUser := resolveConnectHost(dstSpec, &cfg.SyncConfig)
base := func(s Spec, remoteBin string) CtrlMsg {
return CtrlMsg{
BlockSize: cfg.BlockSize, SSHBin: cfg.SSHBin, SSHOpts: cfg.SSHOpts,
ConnectTimeoutSec: cfg.ConnectTimeoutSec, PeerLocal: bothLocal,
}
}
_ = base
// --- copy the boot regions verbatim (offset windows) ---------------
for _, r := range plan.BootRegions {
if r.Length <= 0 {
continue
}
fmt.Fprintf(os.Stderr, "boot region @%d (%s) %s ...\n", r.Offset, humanBytes(r.Length), r.Note)
if err := runWindowTransfer(srcCtrl, dstCtrl, windowJob{
srcPath: srcSpec.Path, dstPath: dstSpec.Path,
srcBase: r.Offset, dstBase: r.Offset, size: r.Length,
bothLocal: bothLocal, blockSize: cfg.BlockSize, cfg: &cfg.SyncConfig,
srcHost: srcHost, srcUser: srcUser, dstHost: dstHost, dstUser: dstUser,
srcRemoteBin: srcRemoteBin, dstRemoteBin: dstRemoteBin,
srcSudo: srcSudo, dstSudo: dstSudo,
}); err != nil {
return fmt.Errorf("boot region @%d: %w", r.Offset, err)
}
}
// --- per-partition data ------------------------------------------------
for i, pp := range plan.Parts {
tag := fmt.Sprintf("partition %d/%d (p%d %s, %s)", i+1, len(plan.Parts), pp.Num, orDash(pp.FSType), pp.Method)
fmt.Fprintf(os.Stderr, "%s ...\n", tag)
switch pp.Method {
case "raw":
sz := pp.SrcSizeB
if pp.DstSizeB < sz {
sz = pp.DstSizeB
}
if err := runWindowTransfer(srcCtrl, dstCtrl, windowJob{
srcPath: srcSpec.Path, dstPath: dstSpec.Path,
srcBase: pp.SrcStartB, dstBase: pp.DstStartB, size: sz,
bothLocal: bothLocal, blockSize: cfg.BlockSize, cfg: &cfg.SyncConfig,
srcHost: srcHost, srcUser: srcUser, dstHost: dstHost, dstUser: dstUser,
srcRemoteBin: srcRemoteBin, dstRemoteBin: dstRemoteBin,
srcSudo: srcSudo, dstSudo: dstSudo,
}); err != nil {
return fmt.Errorf("%s: %w", tag, err)
}
case "fs-image":
if err := runFSImagePartition(srcCtrl, dstCtrl, pp, cloneCtx{
srcPath: srcSpec.Path, dstPath: dstSpec.Path, bothLocal: bothLocal,
cfg: &cfg.SyncConfig, srcHost: srcHost, srcUser: srcUser,
dstHost: dstHost, dstUser: dstUser,
srcRemoteBin: srcRemoteBin, dstRemoteBin: dstRemoteBin,
srcSudo: srcSudo, dstSudo: dstSudo,
}); err != nil {
return fmt.Errorf("%s: %w", tag, err)
}
case "file-level":
return fmt.Errorf("%s: file-level clone is not implemented yet", tag)
}
}
// --- bootloader (opt-in) --------------------------------------------
if cfg.ReinstallBoot {
bootJSON, _ := json.Marshal(bootOpts{
RootPart: plan.RootPart, ESPPart: plan.ESPPart, UEFI: plan.UEFI, DiskPath: dstSpec.Path,
})
fmt.Fprintf(os.Stderr, "reinstalling bootloader on %s ...\n", dstSpec)
summary, err := dstCtrl.ReinstallBoot(dstSpec.Path, string(bootJSON))
if err != nil {
fmt.Fprintf(os.Stderr, " bootloader: %v\n", err)
} else {
fmt.Fprintf(os.Stderr, " bootloader: %s\n", summary)
}
}
label := cfg.Job
if label == "" {
label = fmt.Sprintf("%s -> %s", srcSpec, dstSpec)
}
fmt.Fprintf(os.Stderr, "done: %s\n", label)
return nil
}
// bringUpProbe starts a source control agent and runs probe_disk, retrying
// once under sudo on a permission error (mirrors bringUpController).
func bringUpProbe(spec Spec, tag string, cfg *SyncConfig, remoteBin string) (*Controller, *DiskLayout, bool, error) {
sudo := cfg.Sudo == "always" && canElevate()
c, err := startController(spec, tag, cfg, remoteBin, sudo)
if err != nil {
return nil, nil, sudo, err
}
lay, err := c.ProbeDisk(spec.Path)
if err == nil {
return c, lay, sudo, nil
}
if errors.Is(err, errNeedPriv) && cfg.Sudo == "auto" && !sudo && canElevate() {
fmt.Fprintf(os.Stderr, "%s: permission denied on %s; retrying via sudo ...\n", tag, spec.Path)
c.Close()
sudo = true
if c, err = startController(spec, tag, cfg, remoteBin, true); err != nil {
return nil, nil, sudo, err
}
if lay, err = c.ProbeDisk(spec.Path); err == nil {
return c, lay, sudo, nil
}
}
c.Close()
return nil, nil, sudo, err
}
func reportMissingTools(d *DiskLayout) {
want := []string{"sfdisk", "ntfsclone", "partclone.extfs", "partclone.restore", "e2image"}
var miss []string
for _, t := range want {
if !d.Tools[t] {
miss = append(miss, t)
}
}
if len(miss) > 0 {
fmt.Fprintf(os.Stderr, " note: not present on source: %s (affected partitions fall back to raw block copy)\n",
strings.Join(miss, ", "))
}
}
func orDash(s string) string {
if s == "" {
return "-"
}
return s
}
func intSet(xs []int) map[int]bool {
m := make(map[int]bool, len(xs))
for _, x := range xs {
m[x] = true
}
return m
}
func sortedParts(ps []Partition) []Partition {
out := append([]Partition(nil), ps...)
sort.Slice(out, func(i, j int) bool { return out[i].Start < out[j].Start })
return out
}

117
clonedrive.go Normal file
View File

@ -0,0 +1,117 @@
package main
import (
"fmt"
"os"
)
// windowJob raw-copies a byte window [srcBase,srcBase+size) of the source
// disk onto [dstBase,dstBase+size) of the target, through the same
// push/pull block-diff engine `sync` uses. Used for boot regions and for
// partitions cloned with method "raw".
type windowJob struct {
srcPath, dstPath string
srcBase, dstBase int64
size int64
bothLocal bool
blockSize int64
cfg *SyncConfig
srcHost, srcUser string
dstHost, dstUser string
srcRemoteBin string
dstRemoteBin string
srcSudo, dstSudo bool
}
func runWindowTransfer(srcCtrl, dstCtrl *Controller, j windowJob) error {
pp := newProgressPrinter(j.blockSize)
cb := transferCallbacks{onProgress: pp.print}
pushReq := CtrlMsg{
Path: j.srcPath, Base: j.srcBase, PeerBase: j.dstBase, Size: j.size, BlockSize: j.blockSize,
PeerHost: j.dstHost, PeerUser: j.dstUser, PeerPath: j.dstPath, PeerLocal: j.bothLocal,
RemoteBin: j.dstRemoteBin, SSHBin: j.cfg.SSHBin, SSHOpts: j.cfg.SSHOpts,
ConnectTimeoutSec: j.cfg.ConnectTimeoutSec, Sudo: j.dstSudo,
}
ok, reason, err := srcCtrl.ConnectPush(pushReq, cb)
if err != nil {
pp.finish()
return err
}
if !ok {
pp.finish()
fmt.Fprintf(os.Stderr, " push not possible (%s); pulling instead ...\n", reason)
pullReq := CtrlMsg{
Path: j.dstPath, Base: j.dstBase, PeerBase: j.srcBase, Size: j.size, BlockSize: j.blockSize,
PeerHost: j.srcHost, PeerUser: j.srcUser, PeerPath: j.srcPath, PeerLocal: j.bothLocal,
RemoteBin: j.srcRemoteBin, SSHBin: j.cfg.SSHBin, SSHOpts: j.cfg.SSHOpts,
ConnectTimeoutSec: j.cfg.ConnectTimeoutSec, Sudo: j.srcSudo,
}
ok2, reason2, err2 := dstCtrl.ConnectPull(pullReq, cb)
if err2 != nil {
pp.finish()
return err2
}
if !ok2 {
pp.finish()
return fmt.Errorf("no direct connection either way (push: %s; pull: %s)", reason, reason2)
}
}
pp.finish()
return nil
}
// cloneCtx carries the transport context for an fs-image partition clone.
type cloneCtx struct {
srcPath, dstPath string
bothLocal bool
cfg *SyncConfig
srcHost, srcUser string
dstHost, dstUser string
srcRemoteBin string
dstRemoteBin string
srcSudo, dstSudo bool
}
// runFSImagePartition streams a filesystem image for one partition, trying
// push (source drives) then pull (dest drives).
func runFSImagePartition(srcCtrl, dstCtrl *Controller, pp plannedPart, c cloneCtx) error {
opts := fsCloneOpts{FSType: pp.FSType, Tool: pp.Tool, SizeBytes: pp.SrcSizeB, ShrinkToBytes: pp.ShrinkToB}
prog := newProgressPrinter(1 << 20)
cb := transferCallbacks{onProgress: prog.printBytes}
pushReq := CtrlMsg{
Method: "fs-image", PartIndex: pp.Num, Options: opts.encode(),
Path: c.srcPath, PeerPath: c.dstPath, PeerLocal: c.bothLocal,
PeerHost: c.dstHost, PeerUser: c.dstUser,
RemoteBin: c.dstRemoteBin, SSHBin: c.cfg.SSHBin, SSHOpts: c.cfg.SSHOpts,
ConnectTimeoutSec: c.cfg.ConnectTimeoutSec, Sudo: c.dstSudo,
}
ok, reason, err := srcCtrl.ClonePartition(pushReq, cb)
if err != nil {
prog.finish()
return err
}
if !ok {
prog.finish()
fmt.Fprintf(os.Stderr, " fs-image push not possible (%s); pulling instead ...\n", reason)
pullReq := CtrlMsg{
Method: "fs-image", Reason: "pull", PartIndex: pp.Num, Options: opts.encode(),
Path: c.dstPath, PeerPath: c.srcPath, PeerLocal: c.bothLocal,
PeerHost: c.srcHost, PeerUser: c.srcUser,
RemoteBin: c.srcRemoteBin, SSHBin: c.cfg.SSHBin, SSHOpts: c.cfg.SSHOpts,
ConnectTimeoutSec: c.cfg.ConnectTimeoutSec, Sudo: c.srcSudo,
}
ok2, reason2, err2 := dstCtrl.ClonePartition(pullReq, cb)
if err2 != nil {
prog.finish()
return err2
}
if !ok2 {
prog.finish()
return fmt.Errorf("fs-image failed both ways (push: %s; pull: %s)", reason, reason2)
}
}
prog.finish()
return nil
}

63
control.go
View File

@ -135,6 +135,69 @@ func (c *Controller) agentErr(op, path string, resp CtrlMsg) error {
return fmt.Errorf("%s: %s %s: %s", c.tag, op, path, resp.Message) return fmt.Errorf("%s: %s %s: %s", c.tag, op, path, resp.Message)
} }
// ProbeDisk asks the agent to enumerate a whole disk (partition table, boot
// regions, per-partition filesystem facts, tool availability).
func (c *Controller) ProbeDisk(path string) (*DiskLayout, error) {
resp, err := c.call(CtrlMsg{Type: msgProbeDisk, Path: path})
if err != nil {
return nil, err
}
switch resp.Type {
case msgProbeDiskOK:
return parseDiskLayoutJSON(resp.LayoutJSON)
case msgError:
return nil, c.agentErr("probe", path, resp)
default:
return nil, fmt.Errorf("%s: unexpected response %q to probe_disk", c.tag, resp.Type)
}
}
// BuildLayout asks the agent to create/size an image and write the partition
// table (optsJSON is a buildOpts blob).
func (c *Controller) BuildLayout(path, optsJSON string) error {
resp, err := c.call(CtrlMsg{Type: msgBuildLayout, Path: path, Options: optsJSON})
if err != nil {
return err
}
switch resp.Type {
case msgBuildLayoutOK:
return nil
case msgError:
return c.agentErr("build_layout", path, resp)
default:
return fmt.Errorf("%s: unexpected response %q to build_layout", c.tag, resp.Type)
}
}
// ClonePartition drives one fs-image or file-level partition clone. dir is
// "push" (send to source agent) or "pull" (send to dest agent).
func (c *Controller) ClonePartition(req CtrlMsg, cb transferCallbacks) (ok bool, reason string, err error) {
req.Type = msgClonePartition
okType, failType := msgPushOK, msgPushFailed
if req.Reason == "pull" {
okType, failType = msgPullOK, msgPullFailed
}
return c.connectAndPump(req, cb, okType, failType)
}
// ReinstallBoot asks the (dest) agent to run grub-install/bcdboot; the
// returned string is a human summary. Best-effort — never returns an error
// for a boot-repair failure, only for a transport failure.
func (c *Controller) ReinstallBoot(path, optsJSON string) (string, error) {
resp, err := c.call(CtrlMsg{Type: msgReinstallBoot, Path: path, Options: optsJSON})
if err != nil {
return "", err
}
switch resp.Type {
case msgReinstallBootOK:
return resp.Message, nil
case msgError:
return "", c.agentErr("reinstall_boot", path, resp)
default:
return "", fmt.Errorf("%s: unexpected response %q to reinstall_boot", c.tag, resp.Type)
}
}
// transferCallbacks receives streaming updates while a connect_push or // transferCallbacks receives streaming updates while a connect_push or
// connect_pull is in flight. // connect_pull is in flight.
type transferCallbacks struct { type transferCallbacks struct {

32
ctrlmsg.go
View File

@ -21,6 +21,15 @@ type CtrlMsg struct {
PeerUser string `json:"peerUser,omitempty"` PeerUser string `json:"peerUser,omitempty"`
PeerPort int `json:"peerPort,omitempty"` PeerPort int `json:"peerPort,omitempty"`
PeerPath string `json:"peerPath,omitempty"` PeerPath string `json:"peerPath,omitempty"`
// Base/Length restrict a push/pull transfer to a byte window of the
// path (offset Base, Length bytes). Used by clone-disk to raw-copy a
// boot region or an offset-addressed partition through the same engine.
// Size stays the *window* length for the loop math; Base shifts every
// block offset. Zero Base + Length==Size is the whole-file case that
// `sync` uses unchanged.
Base int64 `json:"base,omitempty"`
PeerBase int64 `json:"peerBase,omitempty"`
Length int64 `json:"length,omitempty"`
// PeerLocal is set when both source and dest are local to the manager, // PeerLocal is set when both source and dest are local to the manager,
// so the driver (itself already a local child of the manager) can spawn // so the driver (itself already a local child of the manager) can spawn
// the sink/source-stream helper as a plain local subprocess instead of // the sink/source-stream helper as a plain local subprocess instead of
@ -48,6 +57,20 @@ type CtrlMsg struct {
Skipped int64 `json:"skipped,omitempty"` Skipped int64 `json:"skipped,omitempty"`
TotalBlocks int64 `json:"totalBlocks,omitempty"` TotalBlocks int64 `json:"totalBlocks,omitempty"`
BytesCopied int64 `json:"bytesCopied,omitempty"` BytesCopied int64 `json:"bytesCopied,omitempty"`
BytesTotal int64 `json:"bytesTotal,omitempty"`
// clone-disk staging: which partition/step of the whole-disk job the
// progress or status refers to. Stage is a short human label
// ("partition table", "boot region", "ntfs p2", "bootloader").
Stage string `json:"stage,omitempty"`
PartIndex int `json:"partIndex,omitempty"`
PartTotal int `json:"partTotal,omitempty"`
// clone-disk payloads: probe result / requested target layout, both
// carried as embedded JSON so CtrlMsg stays a flat envelope.
LayoutJSON string `json:"layoutJSON,omitempty"`
Method string `json:"method,omitempty"` // partition clone method: "fs-image" | "raw" | "file-level"
Options string `json:"options,omitempty"` // JSON of the build/clone options block
// log // log
Level string `json:"level,omitempty"` Level string `json:"level,omitempty"`
@ -69,4 +92,13 @@ const (
msgError = "error" msgError = "error"
msgClose = "close" msgClose = "close"
msgBye = "bye" msgBye = "bye"
// clone-disk control verbs
msgProbeDisk = "probe_disk"
msgProbeDiskOK = "probe_disk_ok"
msgBuildLayout = "build_layout"
msgBuildLayoutOK = "build_layout_ok"
msgClonePartition = "clone_partition"
msgReinstallBoot = "reinstall_boot"
msgReinstallBootOK = "reinstall_boot_ok"
) )

322
disk_linux.go Normal file
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@ -0,0 +1,322 @@
//go:build linux
package main
import (
"encoding/base64"
"fmt"
"os"
"os/exec"
"strconv"
"strings"
"unsafe"
"syscall"
)
// BLKSSZGET returns the logical (soft) sector size of a block device.
const blkSSZGet = 0x1268
func logicalSectorSize(path string) (int64, error) {
fi, err := os.Stat(path)
if err == nil && fi.Mode().IsRegular() {
return 512, nil
}
f, err := os.Open(path)
if err != nil {
return 512, err
}
defer f.Close()
var ssz int32
_, _, errno := syscall.Syscall(syscall.SYS_IOCTL, f.Fd(), blkSSZGet, uintptr(unsafe.Pointer(&ssz)))
if errno != 0 || ssz <= 0 {
return 512, nil
}
return int64(ssz), nil
}
// diskAttachment is a probe-time view of a whole disk: the block path whose
// partitions can be opened (the disk itself for a real device, a loop device
// for an image file) plus a cleanup to release a loop device.
type diskAttachment struct {
blockPath string
cleanup func()
}
// attachDisk returns a block path whose partition nodes exist. For a regular
// file it sets up a partition-scanning loop device; for a real block device
// it is a no-op.
func attachDisk(path string, writable bool) (*diskAttachment, error) {
fi, err := os.Stat(path)
if err != nil {
return nil, err
}
if fi.Mode()&os.ModeDevice != 0 {
return &diskAttachment{blockPath: path, cleanup: func() {}}, nil
}
args := []string{"--find", "--show", "--partscan"}
if !writable {
args = append(args, "--read-only")
}
args = append(args, path)
out, err := exec.Command("losetup", args...).Output()
if err != nil {
return nil, fmt.Errorf("losetup %s: %w", path, cmdErr(err))
}
lo := strings.TrimSpace(string(out))
return &diskAttachment{
blockPath: lo,
cleanup: func() { _ = exec.Command("losetup", "--detach", lo).Run() },
}, nil
}
// partNode maps a whole-disk block path + 1-based partition number to its
// partition device node (sda -> sda1, nvme0n1 -> nvme0n1p1, loop0 -> loop0p1).
func partNode(disk string, num int) string {
if l := len(disk); l > 0 && disk[l-1] >= '0' && disk[l-1] <= '9' {
return fmt.Sprintf("%sp%d", disk, num)
}
return fmt.Sprintf("%s%d", disk, num)
}
var diskTools = []string{
"sfdisk", "sgdisk", "partprobe", "blockdev", "blkid", "lsblk", "losetup",
"ntfsclone", "ntfsresize", "ntfsfix", "mkntfs",
"e2image", "resize2fs", "dumpe2fs", "mkfs.ext4", "e2fsck",
"partclone.dd", "partclone.extfs", "partclone.ntfs", "partclone.fat",
"partclone.exfat", "partclone.xfs", "partclone.btrfs", "partclone.restore",
"xfs_copy", "mkfs.vfat", "mkfs.xfs", "mkswap", "rsync",
"mount", "umount", "grub-install", "update-grub", "grub-mkconfig",
}
func probeToolset() map[string]bool {
m := make(map[string]bool, len(diskTools))
for _, t := range diskTools {
if _, err := exec.LookPath(t); err == nil {
m[t] = true
}
}
return m
}
// probeDiskLayout gathers everything clone-disk needs from a source disk.
func probeDiskLayout(path string) (*DiskLayout, error) {
d := &DiskLayout{DiskPath: path, Tools: probeToolset()}
info, err := statPath(path)
if err != nil {
return nil, err
}
if !info.Exists {
return nil, fmt.Errorf("%s does not exist", path)
}
d.DiskSize = info.Size
if d.LogicalSector, err = logicalSectorSize(path); err != nil {
d.LogicalSector = 512
}
d.PhysicalSector = d.LogicalSector
// Partition table via sfdisk -d (works on a file directly).
dump, derr := exec.Command("sfdisk", "-d", path).Output()
if derr != nil {
d.Scheme = "raw"
d.Warnings = append(d.Warnings, fmt.Sprintf("no partition table (%v)", cmdErr(derr)))
return d, nil
}
if err := d.parseSfdiskDump(string(dump)); err != nil {
return nil, err
}
if d.LogicalSector == 0 {
d.LogicalSector = 512
}
if d.Scheme == "gpt" {
if b, err := exec.Command("sgdisk", "--backup=/dev/stdout", path).Output(); err == nil {
d.SgdiskB64 = base64.StdEncoding.EncodeToString(b)
}
}
// Attach so per-partition nodes exist, then enrich each row.
att, err := attachDisk(path, false)
if err != nil {
d.Warnings = append(d.Warnings, fmt.Sprintf("cannot attach for fs probe: %v", err))
} else {
defer att.cleanup()
for i := range d.Partitions {
enrichPartition(&d.Partitions[i], att.blockPath, d.LogicalSector)
}
}
d.BootRegions = computeBootRegions(d)
return d, nil
}
// enrichPartition fills the FS* fields of p using blkid + fs-specific probes.
func enrichPartition(p *Partition, disk string, sector int64) {
node := partNode(disk, p.Num)
p.DevPath = node
if _, err := os.Stat(node); err != nil {
return
}
if out, err := exec.Command("blkid", "-o", "export", node).Output(); err == nil {
for _, line := range strings.Split(string(out), "\n") {
k, v, ok := splitEq(strings.TrimSpace(line))
if !ok {
continue
}
switch k {
case "TYPE":
p.FSType = v
case "LABEL":
p.FSLabel = v
case "UUID":
p.FSUUID = v
}
}
}
switch p.FSType {
case "ext2", "ext3", "ext4":
p.FSUsedBytes, p.FSMinBytes = probeExtSizes(node)
case "ntfs":
p.FSUsedBytes, p.FSMinBytes = probeNTFSSizes(node)
}
}
func probeExtSizes(node string) (used, min int64) {
if out, err := exec.Command("dumpe2fs", "-h", node).Output(); err == nil {
var bs, count, free int64
for _, line := range strings.Split(string(out), "\n") {
f := strings.SplitN(line, ":", 2)
if len(f) != 2 {
continue
}
v := strings.TrimSpace(f[1])
switch strings.TrimSpace(f[0]) {
case "Block size":
bs, _ = strconv.ParseInt(v, 10, 64)
case "Block count":
count, _ = strconv.ParseInt(v, 10, 64)
case "Free blocks":
free, _ = strconv.ParseInt(v, 10, 64)
}
}
if bs > 0 && count > 0 {
used = (count - free) * bs
}
}
// resize2fs -P needs a clean fs; ignore failures.
if out, err := exec.Command("resize2fs", "-P", node).Output(); err == nil {
// "Estimated minimum size of the filesystem: 123456" (in 4k blocks)
s := string(out)
if i := strings.LastIndex(s, ":"); i >= 0 {
if n, err := strconv.ParseInt(strings.TrimSpace(s[i+1:]), 10, 64); err == nil {
min = n * 4096
}
}
}
return used, min
}
func probeNTFSSizes(node string) (used, min int64) {
out, err := exec.Command("ntfsresize", "--info", "--force", node).CombinedOutput()
if err != nil {
return 0, 0
}
for _, line := range strings.Split(string(out), "\n") {
line = strings.TrimSpace(line)
switch {
case strings.HasPrefix(line, "You might resize at "):
// "You might resize at 1234567890 bytes ..."
fields := strings.Fields(line)
if len(fields) >= 5 {
if n, err := strconv.ParseInt(fields[4], 10, 64); err == nil {
min = n
}
}
case strings.Contains(line, "Space in use") && strings.Contains(line, "bytes"):
// "Space in use : 1234 MB (1.2%)" - not bytes; skip
}
}
return min, min
}
// computeBootRegions returns the byte ranges outside any cloned partition
// that must still be copied verbatim.
func computeBootRegions(d *DiskLayout) []Region {
var regs []Region
// bootstrap code before the MBR partition table on both MBR and (BIOS-)GPT disks
regs = append(regs, Region{Offset: 0, Length: 446, Note: "MBR bootstrap"})
if d.Scheme == "mbr" && len(d.Partitions) > 0 {
firstStart := d.Partitions[0].Start * d.LogicalSector
for _, p := range d.Partitions {
s := p.Start * d.LogicalSector
if s > 0 && s < firstStart {
firstStart = s
}
}
if firstStart > 512 {
regs = append(regs, Region{Offset: 512, Length: firstStart - 512, Note: "MBR gap (GRUB core.img etc.)"})
}
}
return regs
}
// applyPartitionTable writes script (an sfdisk restore script) to target,
// which may be a block device or an image file, and re-reads the table.
func applyPartitionTable(target, script string) error {
cmd := exec.Command("sfdisk", "--no-reread", "--no-tell-kernel", "--force", "--wipe=always", target)
cmd.Stdin = strings.NewReader(script)
if out, err := cmd.CombinedOutput(); err != nil {
return fmt.Errorf("sfdisk %s: %v: %s", target, err, strings.TrimSpace(string(out)))
}
rereadPartTable(target)
return nil
}
func rereadPartTable(target string) {
fi, err := os.Stat(target)
if err != nil || fi.Mode()&os.ModeDevice == 0 {
return
}
if err := exec.Command("partprobe", target).Run(); err != nil {
_ = exec.Command("blockdev", "--rereadpt", target).Run()
}
}
// lsblkFSType reports the filesystem type on a node ("" if none).
func lsblkFSType(node string) string {
out, err := exec.Command("lsblk", "-ndo", "FSTYPE", node).Output()
if err != nil {
return ""
}
return strings.TrimSpace(string(out))
}
// mountAt mounts node at a fresh temp dir and returns the dir + an unmount fn.
func mountAt(node string, readonly bool) (string, func(), error) {
dir, err := os.MkdirTemp("", "clonetool-mnt-")
if err != nil {
return "", nil, err
}
args := []string{}
if readonly {
args = append(args, "-o", "ro")
}
args = append(args, node, dir)
if out, err := exec.Command("mount", args...).CombinedOutput(); err != nil {
os.Remove(dir)
return "", nil, fmt.Errorf("mount %s: %v: %s", node, err, strings.TrimSpace(string(out)))
}
return dir, func() {
_ = exec.Command("umount", dir).Run()
_ = os.Remove(dir)
}, nil
}
func cmdErr(err error) error {
if ee, ok := err.(*exec.ExitError); ok {
if s := strings.TrimSpace(string(ee.Stderr)); s != "" {
return fmt.Errorf("%v: %s", err, s)
}
}
return err
}

37
disk_other.go Normal file
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@ -0,0 +1,37 @@
//go:build !linux && !windows
package main
import (
"fmt"
"runtime"
)
func logicalSectorSize(string) (int64, error) { return 512, nil }
type diskAttachment struct {
blockPath string
cleanup func()
}
func attachDisk(string, bool) (*diskAttachment, error) {
return nil, fmt.Errorf("clone-disk is only implemented on linux and windows (this is %s)", runtime.GOOS)
}
func partNode(disk string, num int) string { return fmt.Sprintf("%s%d", disk, num) }
func probeDiskLayout(string) (*DiskLayout, error) {
return nil, fmt.Errorf("clone-disk is only implemented on linux and windows (this is %s)", runtime.GOOS)
}
func applyPartitionTable(string, string) error {
return fmt.Errorf("clone-disk partition rebuild is only implemented on linux and windows")
}
func rereadPartTable(string) {}
func lsblkFSType(string) string { return "" }
func mountAt(string, bool) (string, func(), error) {
return "", nil, fmt.Errorf("mount is only implemented on linux")
}

232
disk_windows.go Normal file
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@ -0,0 +1,232 @@
//go:build windows
package main
import (
"encoding/binary"
"fmt"
"os"
"os/exec"
"strings"
"syscall"
)
const (
ioctlDiskGetDriveLayoutEx = 0x00070050 // IOCTL_DISK_GET_DRIVE_LAYOUT_EX
ioctlDiskUpdateProperties = 0x00070140 // IOCTL_DISK_UPDATE_PROPERTIES
)
func logicalSectorSize(path string) (int64, error) {
if !isDevicePath(path) {
return 512, nil
}
return alignmentFor(path), nil
}
// guidString renders a little-endian Win32 GUID (4-2-2 + 8 bytes) as the
// canonical upper-case string.
func guidString(b []byte) string {
if len(b) < 16 {
return ""
}
d1 := binary.LittleEndian.Uint32(b[0:4])
d2 := binary.LittleEndian.Uint16(b[4:6])
d3 := binary.LittleEndian.Uint16(b[6:8])
return strings.ToUpper(fmt.Sprintf("%08X-%04X-%04X-%02X%02X-%02X%02X%02X%02X%02X%02X",
d1, d2, d3, b[8], b[9], b[10], b[11], b[12], b[13], b[14], b[15]))
}
// probeDiskLayout reads the partition table of a \\.\PhysicalDriveN via
// IOCTL_DISK_GET_DRIVE_LAYOUT_EX. Windows-native clone-disk is raw/VSS only:
// every partition is cloned block-wise and the table itself is reproduced by
// raw-copying the leading sectors (see computeBootRegionsWindows), so no
// sfdisk-style rebuild is needed.
func probeDiskLayout(path string) (*DiskLayout, error) {
d := &DiskLayout{DiskPath: path, Tools: probeToolsetWindows()}
info, err := statPath(path)
if err != nil {
return nil, err
}
if !info.Exists {
return nil, fmt.Errorf("%s does not exist", path)
}
d.DiskSize = info.Size
d.LogicalSector, _ = logicalSectorSize(path)
if d.LogicalSector == 0 {
d.LogicalSector = 512
}
d.PhysicalSector = d.LogicalSector
if !isDevicePath(path) {
// An image file: we cannot enumerate its table without extra tooling.
d.Scheme = "raw"
d.Warnings = append(d.Warnings, "image-file source on Windows: whole-image raw clone only")
return d, nil
}
p16, err := syscall.UTF16PtrFromString(path)
if err != nil {
return nil, err
}
h, err := syscall.CreateFile(p16, syscall.GENERIC_READ,
syscall.FILE_SHARE_READ|syscall.FILE_SHARE_WRITE, nil, syscall.OPEN_EXISTING, 0, 0)
if err != nil {
return nil, &os.PathError{Op: "open", Path: path, Err: err}
}
defer syscall.CloseHandle(h)
buf := make([]byte, 64*1024)
var ret uint32
if err := syscall.DeviceIoControl(h, ioctlDiskGetDriveLayoutEx, nil, 0,
&buf[0], uint32(len(buf)), &ret, nil); err != nil {
return nil, fmt.Errorf("IOCTL_DISK_GET_DRIVE_LAYOUT_EX %s: %w", path, err)
}
style := binary.LittleEndian.Uint32(buf[0:4])
count := binary.LittleEndian.Uint32(buf[4:8])
switch style {
case 0:
d.Scheme, d.Label = "mbr", "dos"
sig := binary.LittleEndian.Uint32(buf[8:12])
d.LabelID = fmt.Sprintf("0x%08x", sig)
case 1:
d.Scheme, d.Label = "gpt", "gpt"
d.LabelID = guidString(buf[8:24])
default:
d.Scheme = "raw"
}
const hdr = 48
const peSize = 144
sector := d.LogicalSector
for i := uint32(0); i < count; i++ {
off := hdr + int(i)*peSize
if off+peSize > len(buf) {
break
}
e := buf[off : off+peSize]
start := int64(binary.LittleEndian.Uint64(e[8:16]))
length := int64(binary.LittleEndian.Uint64(e[16:24]))
num := int(binary.LittleEndian.Uint32(e[24:28]))
if length == 0 || num == 0 {
continue
}
p := Partition{
Num: num,
Start: start / sector,
Size: length / sector,
}
if style == 1 { // GPT union at offset 32
p.Type = guidString(e[32:48])
p.UUID = guidString(e[48:64])
p.Name = decodeUTF16(e[72:144])
} else if style == 0 { // MBR union at offset 32
p.Type = fmt.Sprintf("%02x", e[32])
if e[33] != 0 {
p.Attrs = "bootable"
}
}
d.Partitions = append(d.Partitions, p)
}
d.BootRegions = computeBootRegionsWindows(d)
return d, nil
}
func decodeUTF16(b []byte) string {
u := make([]uint16, 0, len(b)/2)
for i := 0; i+1 < len(b); i += 2 {
c := binary.LittleEndian.Uint16(b[i : i+2])
if c == 0 {
break
}
u = append(u, c)
}
return strings.TrimRight(syscall.UTF16ToString(u), "\x00")
}
// computeBootRegionsWindows: reproduce the partition table by raw-copying the
// sectors before the first partition, plus the trailing 33 sectors that hold
// the backup GPT.
func computeBootRegionsWindows(d *DiskLayout) []Region {
var regs []Region
if len(d.Partitions) == 0 {
return regs
}
first := d.Partitions[0].Start * d.LogicalSector
for _, p := range d.Partitions {
if s := p.Start * d.LogicalSector; s > 0 && s < first {
first = s
}
}
if first > 0 {
regs = append(regs, Region{Offset: 0, Length: first, Note: "protective MBR + primary GPT / MBR table + gap"})
}
if d.Scheme == "gpt" && d.DiskSize > 33*d.LogicalSector {
regs = append(regs, Region{
Offset: d.DiskSize - 33*d.LogicalSector,
Length: 33 * d.LogicalSector,
Note: "backup GPT",
})
}
return regs
}
func rereadPartTable(target string) {
if !isDevicePath(target) {
return
}
p16, err := syscall.UTF16PtrFromString(target)
if err != nil {
return
}
h, err := syscall.CreateFile(p16, syscall.GENERIC_READ|syscall.GENERIC_WRITE,
syscall.FILE_SHARE_READ|syscall.FILE_SHARE_WRITE, nil, syscall.OPEN_EXISTING, 0, 0)
if err != nil {
return
}
defer syscall.CloseHandle(h)
var ret uint32
_ = syscall.DeviceIoControl(h, ioctlDiskUpdateProperties, nil, 0, nil, 0, &ret, nil)
}
// applyPartitionTable is a no-op on Windows: the table is reproduced via the
// raw boot regions and rereadPartTable() refreshes the kernel's view.
func applyPartitionTable(target, script string) error {
rereadPartTable(target)
return nil
}
func probeToolsetWindows() map[string]bool {
m := map[string]bool{}
for _, t := range []string{"vssadmin", "wmic", "bcdboot", "diskpart", "robocopy", "powershell"} {
if _, err := exec.LookPath(t); err == nil {
m[t] = true
}
}
return m
}
type diskAttachment struct {
blockPath string
cleanup func()
}
// attachDisk is a no-op for a raw \\.\PhysicalDriveN (partitions are addressed
// by byte offset within the whole-disk handle on Windows) and unsupported for
// an image file.
func attachDisk(path string, writable bool) (*diskAttachment, error) {
if isDevicePath(path) {
return &diskAttachment{blockPath: path, cleanup: func() {}}, nil
}
return nil, fmt.Errorf("filesystem-aware / file-level clone of an image file is not supported on Windows; use --raw")
}
func partNode(disk string, num int) string { return fmt.Sprintf("%s (partition %d)", disk, num) }
func lsblkFSType(string) string { return "" }
func mountAt(string, bool) (string, func(), error) {
return "", nil, fmt.Errorf("mount-based file-level clone is not supported on Windows; use --raw")
}

298
disklayout.go Normal file
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@ -0,0 +1,298 @@
package main
import (
"bufio"
"encoding/json"
"fmt"
"strconv"
"strings"
)
// DiskLayout is the full picture of a source disk that clone-disk needs to
// reproduce a target: the partition table (as parsed from `sfdisk -d`, the
// canonical restorable form for both GPT and MBR), the byte ranges outside
// any partition that still have to be copied verbatim (MBR bootstrap + gap,
// BIOS-boot partition), the per-partition filesystem facts, and which of the
// external tools we shell out to are actually present.
type DiskLayout struct {
// Whole-disk geometry.
DiskPath string `json:"diskPath"`
DiskSize int64 `json:"diskSize"` // bytes
LogicalSector int64 `json:"logicalSector"` // bytes, from the kernel/ioctl
PhysicalSector int64 `json:"physicalSector"` // bytes
Scheme string `json:"scheme"` // "gpt" | "mbr" | "raw" (no recognisable table)
// Partition table, parsed from `sfdisk -d`.
Label string `json:"label"` // "gpt" | "dos"
LabelID string `json:"labelID"` // GPT disk GUID / MBR 4-byte signature (0x...)
FirstLBA int64 `json:"firstLBA"` // sectors; 0 if the dump omitted it
LastLBA int64 `json:"lastLBA"` // sectors; 0 if omitted
Partitions []Partition `json:"partitions"`
SfdiskDump string `json:"sfdiskDump"` // the verbatim `sfdisk -d` output
SgdiskB64 string `json:"sgdiskB64"` // base64 `sgdisk --backup` blob (GPT only), fallback restore path
// Byte ranges that must be raw-copied and are not covered by a cloned
// partition: MBR bootstrap (0..0x1BE) + the gap before the first
// partition, and any BIOS-boot partition.
BootRegions []Region `json:"bootRegions"`
Tools map[string]bool `json:"tools"` // external tool name -> present on PATH
Warnings []string `json:"warnings,omitempty"`
}
// Region is a [Offset, Offset+Length) byte window on the whole disk.
type Region struct {
Offset int64 `json:"offset"`
Length int64 `json:"length"`
Note string `json:"note,omitempty"`
}
// Partition is one row of the partition table plus the filesystem facts the
// source agent gathered for it.
type Partition struct {
Num int `json:"num"`
Start int64 `json:"start"` // sectors
Size int64 `json:"size"` // sectors
Type string `json:"type"` // GPT type GUID or MBR hex code
UUID string `json:"uuid"` // GPT partition GUID (PARTUUID)
Name string `json:"name"` // GPT partition name
Attrs string `json:"attrs"` // trailing flags: "bootable", "attrs=\"...\"", ...
// Filesystem facts (source agent; not from sfdisk).
DevPath string `json:"devPath"` // source node, e.g. /dev/sda2
FSType string `json:"fsType"` // ext4 | ntfs | vfat | xfs | btrfs | swap | "" (none/unknown)
FSLabel string `json:"fsLabel"`
FSUUID string `json:"fsUUID"`
FSUsedBytes int64 `json:"fsUsedBytes"` // 0 if unknown
FSMinBytes int64 `json:"fsMinBytes"` // smallest the fs can be shrunk to; 0 if unknown/unshrinkable
}
// StartBytes / SizeBytes convert the sector-unit table fields using the
// disk's logical sector size.
func (p Partition) StartBytes(sectorSize int64) int64 { return p.Start * sectorSize }
func (p Partition) SizeBytes(sectorSize int64) int64 { return p.Size * sectorSize }
func (d *DiskLayout) JSON() string {
b, _ := json.Marshal(d)
return string(b)
}
func parseDiskLayoutJSON(s string) (*DiskLayout, error) {
var d DiskLayout
if err := json.Unmarshal([]byte(s), &d); err != nil {
return nil, fmt.Errorf("decode disk layout: %w", err)
}
return &d, nil
}
// parseSfdiskDump fills the Label/LabelID/FirstLBA/LastLBA/Partitions fields
// of d from the text of `sfdisk -d`. It leaves the raw text in d.SfdiskDump.
func (d *DiskLayout) parseSfdiskDump(dump string) error {
d.SfdiskDump = dump
sc := bufio.NewScanner(strings.NewReader(dump))
sc.Buffer(make([]byte, 64*1024), 1024*1024)
for sc.Scan() {
line := strings.TrimSpace(sc.Text())
if line == "" {
continue
}
if i := strings.Index(line, " : "); i >= 0 && strings.Contains(line, "start=") {
p, err := parseSfdiskPartLine(line)
if err != nil {
return err
}
d.Partitions = append(d.Partitions, p)
continue
}
key, val, ok := splitKV(line)
if !ok {
continue
}
switch key {
case "label":
d.Label = val
case "label-id":
d.LabelID = val
case "first-lba":
d.FirstLBA, _ = strconv.ParseInt(val, 10, 64)
case "last-lba":
d.LastLBA, _ = strconv.ParseInt(val, 10, 64)
case "sector-size":
if n, err := strconv.ParseInt(val, 10, 64); err == nil && d.LogicalSector == 0 {
d.LogicalSector = n
}
}
}
if err := sc.Err(); err != nil {
return fmt.Errorf("scan sfdisk dump: %w", err)
}
switch d.Label {
case "gpt":
d.Scheme = "gpt"
case "dos":
d.Scheme = "mbr"
}
return nil
}
// splitKV parses a "key: value" header line.
func splitKV(line string) (string, string, bool) {
i := strings.Index(line, ":")
if i < 0 {
return "", "", false
}
return strings.TrimSpace(line[:i]), strings.TrimSpace(line[i+1:]), true
}
// parseSfdiskPartLine parses a body line like
//
// /dev/sda2 : start= 1050624, size= 1951xxxxxx, type=0FC6..., uuid=..., name="root", attrs="..."
// /dev/sda1 : start= 2048, size= 204800, type=83, bootable
func parseSfdiskPartLine(line string) (Partition, error) {
var p Partition
i := strings.Index(line, " : ")
dev := strings.TrimSpace(line[:i])
p.DevPath = dev
p.Num = trailingInt(dev)
rest := line[i+3:]
for _, fld := range splitTopLevel(rest, ',') {
fld = strings.TrimSpace(fld)
if fld == "" {
continue
}
k, v, ok := splitEq(fld)
if !ok {
// bare flag, e.g. "bootable"
if p.Attrs == "" {
p.Attrs = fld
} else {
p.Attrs += ", " + fld
}
continue
}
v = strings.Trim(strings.TrimSpace(v), `"`)
switch k {
case "start":
p.Start, _ = strconv.ParseInt(strings.TrimSpace(v), 10, 64)
case "size":
p.Size, _ = strconv.ParseInt(strings.TrimSpace(v), 10, 64)
case "type":
p.Type = v
case "uuid":
p.UUID = v
case "name":
p.Name = v
case "attrs":
if p.Attrs == "" {
p.Attrs = `attrs="` + v + `"`
} else {
p.Attrs += `, attrs="` + v + `"`
}
}
}
if p.Start == 0 && p.Size == 0 {
return p, fmt.Errorf("sfdisk line without start/size: %q", line)
}
return p, nil
}
// sfdiskRestoreScript renders a device-independent script that recreates this
// table on any target with `sfdisk`. It intentionally drops `device:` and the
// per-line device prefixes (sfdisk numbers the partitions in order) and
// `last-lba` (let sfdisk size the secondary GPT for the target). label-id and
// per-partition uuid are dropped when newIDs is set so a replacement disk can
// coexist with the original; otherwise they are preserved so existing
// BCD/fstab/GRUB references still resolve. sizeOverride maps a 1-based
// partition number to a new size in sectors (used by the shrink path).
func (d *DiskLayout) sfdiskRestoreScript(newIDs bool, sizeOverride map[int]int64) string {
var b strings.Builder
fmt.Fprintf(&b, "label: %s\n", d.Label)
if d.LabelID != "" && !newIDs {
fmt.Fprintf(&b, "label-id: %s\n", d.LabelID)
}
if d.FirstLBA > 0 {
fmt.Fprintf(&b, "first-lba: %d\n", d.FirstLBA)
}
if d.LogicalSector > 0 {
fmt.Fprintf(&b, "sector-size: %d\n", d.LogicalSector)
}
b.WriteString("unit: sectors\n\n")
for _, p := range d.Partitions {
size := p.Size
if ov, ok := sizeOverride[p.Num]; ok && ov > 0 {
size = ov
}
fmt.Fprintf(&b, "start=%d, size=%d", p.Start, size)
if p.Type != "" {
fmt.Fprintf(&b, ", type=%s", p.Type)
}
if p.UUID != "" && !newIDs {
fmt.Fprintf(&b, ", uuid=%s", p.UUID)
}
if p.Name != "" {
fmt.Fprintf(&b, ", name=\"%s\"", p.Name)
}
if p.Attrs != "" {
fmt.Fprintf(&b, ", %s", p.Attrs)
}
b.WriteByte('\n')
}
return b.String()
}
// biosBootType / espType are the GPT type GUIDs clone-disk special-cases.
const (
gptBIOSBoot = "21686148-6449-6E6F-744E-656564454649" // EF02 BIOS boot partition
gptESP = "C12A7328-F81F-11D2-BA4B-00A0C93EC93B" // EF00 EFI system partition
)
func (p Partition) isBIOSBoot() bool {
return strings.EqualFold(p.Type, gptBIOSBoot) || p.Type == "21" /* mbr */
}
func (p Partition) isESP() bool {
return strings.EqualFold(p.Type, gptESP) || p.Type == "ef" || p.Type == "EF"
}
// --- small string helpers -------------------------------------------------
func trailingInt(s string) int {
j := len(s)
for j > 0 && s[j-1] >= '0' && s[j-1] <= '9' {
j--
}
if j == len(s) {
return 0
}
n, _ := strconv.Atoi(s[j:])
return n
}
func splitEq(s string) (string, string, bool) {
i := strings.Index(s, "=")
if i < 0 {
return "", "", false
}
return strings.TrimSpace(s[:i]), s[i+1:], true
}
// splitTopLevel splits on sep but not inside double quotes.
func splitTopLevel(s string, sep byte) []string {
var out []string
var cur strings.Builder
inQ := false
for i := 0; i < len(s); i++ {
c := s[i]
switch {
case c == '"':
inQ = !inQ
cur.WriteByte(c)
case c == sep && !inQ:
out = append(out, cur.String())
cur.Reset()
default:
cur.WriteByte(c)
}
}
out = append(out, cur.String())
return out
}

113
disklayout_test.go Normal file
View File

@ -0,0 +1,113 @@
package main
import (
"strings"
"testing"
)
const gptDump = `label: gpt
label-id: 1D2E3F4A-1111-2222-3333-444455556666
device: /dev/sda
unit: sectors
first-lba: 2048
last-lba: 8388574
sector-size: 512
/dev/sda1 : start= 2048, size= 204800, type=C12A7328-F81F-11D2-BA4B-00A0C93EC93B, uuid=AAAAAAAA-1111-2222-3333-444455556666, name="EFI System Partition"
/dev/sda2 : start= 206848, size= 8179712, type=0FC63DAF-8483-4772-8E79-3D69D8477DE4, uuid=BBBBBBBB-1111-2222-3333-444455556666
`
const mbrDump = `label: dos
label-id: 0x1a2b3c4d
device: /dev/sdb
unit: sectors
sector-size: 512
/dev/sdb1 : start= 2048, size= 512000, type=83, bootable
/dev/sdb2 : start= 514048, size= 41734144, type=83
`
func TestParseSfdiskDumpGPT(t *testing.T) {
var d DiskLayout
if err := d.parseSfdiskDump(gptDump); err != nil {
t.Fatal(err)
}
if d.Label != "gpt" || d.Scheme != "gpt" {
t.Fatalf("label/scheme = %q/%q", d.Label, d.Scheme)
}
if d.LabelID != "1D2E3F4A-1111-2222-3333-444455556666" {
t.Fatalf("labelID = %q", d.LabelID)
}
if d.FirstLBA != 2048 || d.LastLBA != 8388574 {
t.Fatalf("lba = %d/%d", d.FirstLBA, d.LastLBA)
}
if len(d.Partitions) != 2 {
t.Fatalf("parts = %d", len(d.Partitions))
}
p1 := d.Partitions[0]
if p1.Num != 1 || p1.Start != 2048 || p1.Size != 204800 {
t.Fatalf("p1 = %+v", p1)
}
if p1.Type != "C12A7328-F81F-11D2-BA4B-00A0C93EC93B" || p1.UUID != "AAAAAAAA-1111-2222-3333-444455556666" {
t.Fatalf("p1 type/uuid = %q/%q", p1.Type, p1.UUID)
}
if p1.Name != "EFI System Partition" {
t.Fatalf("p1 name = %q", p1.Name)
}
if !p1.isESP() {
t.Fatalf("p1 should be ESP")
}
if d.Partitions[1].Num != 2 || d.Partitions[1].Size != 8179712 {
t.Fatalf("p2 = %+v", d.Partitions[1])
}
}
func TestParseSfdiskDumpMBR(t *testing.T) {
var d DiskLayout
if err := d.parseSfdiskDump(mbrDump); err != nil {
t.Fatal(err)
}
if d.Scheme != "mbr" || d.LabelID != "0x1a2b3c4d" {
t.Fatalf("scheme/id = %q/%q", d.Scheme, d.LabelID)
}
if len(d.Partitions) != 2 || d.Partitions[0].Attrs != "bootable" {
t.Fatalf("parts = %+v", d.Partitions)
}
}
func TestSfdiskRestoreScript(t *testing.T) {
var d DiskLayout
if err := d.parseSfdiskDump(gptDump); err != nil {
t.Fatal(err)
}
// keep IDs
s := d.sfdiskRestoreScript(false, nil)
if !strings.Contains(s, "label-id: 1D2E3F4A-1111-2222-3333-444455556666") {
t.Fatalf("expected label-id kept:\n%s", s)
}
if !strings.Contains(s, "uuid=AAAAAAAA-1111-2222-3333-444455556666") {
t.Fatalf("expected part uuid kept:\n%s", s)
}
if strings.Contains(s, "device:") || strings.Contains(s, "/dev/sda1") {
t.Fatalf("script must be device-independent:\n%s", s)
}
if strings.Contains(s, "last-lba") {
t.Fatalf("script must drop last-lba:\n%s", s)
}
// new IDs
s2 := d.sfdiskRestoreScript(true, nil)
if strings.Contains(s2, "label-id:") || strings.Contains(s2, "uuid=") {
t.Fatalf("--new-ids must strip ids:\n%s", s2)
}
// size override on p2
s3 := d.sfdiskRestoreScript(false, map[int]int64{2: 4000000})
if !strings.Contains(s3, "size=4000000") {
t.Fatalf("expected overridden size:\n%s", s3)
}
if strings.Contains(s3, "size=8179712") {
t.Fatalf("old size should be gone:\n%s", s3)
}
}

200
fsclone.go Normal file
View File

@ -0,0 +1,200 @@
package main
import (
"bufio"
"encoding/json"
"fmt"
"io"
"regexp"
"strconv"
"strings"
)
// fsCloner is the pair of argv templates that stream one filesystem as an
// image: save reads the fs on dev and writes an image to stdout; restore
// reads that image from stdin and writes it onto dev. The image format is
// whatever the chosen standard tool uses (ntfsclone, partclone, e2image) —
// clonetool only moves the bytes between the two ends.
type fsCloner struct {
name string // tool family, for logs
save []string
restore []string
}
// fsCloneOpts is the JSON blob carried in CtrlMsg.Options for a fs-image
// partition clone so both ends build the identical argv.
type fsCloneOpts struct {
FSType string `json:"fsType"`
Tool string `json:"tool"`
SizeBytes int64 `json:"sizeBytes"`
// ShrinkToBytes > 0: shrink the SOURCE filesystem to this size in place
// before imaging it (so it fits a smaller target partition). This
// mutates the source and only runs when the operator passed
// --allow-shrink --yes.
ShrinkToBytes int64 `json:"shrinkToBytes,omitempty"`
}
func (o fsCloneOpts) encode() string { b, _ := json.Marshal(o); return string(b) }
func decodeFSCloneOpts(s string) (fsCloneOpts, error) {
var o fsCloneOpts
err := json.Unmarshal([]byte(s), &o)
return o, err
}
// pickCloner returns the fs-image cloner for (fsType, tool) or nil if the
// partition should be handled some other way. tool is the family name chosen
// by chooseCloneMethod ("ntfsclone", "partclone", "e2image").
func pickCloner(dev, fsType, tool string) *fsCloner {
switch tool {
case "ntfsclone":
return &fsCloner{
name: "ntfsclone",
save: []string{"ntfsclone", "--save-image", "--force", "--output", "-", dev},
restore: []string{"ntfsclone", "--restore-image", "--overwrite", dev, "-"},
}
case "e2image":
return &fsCloner{
name: "e2image",
// -ra: raw + skip unallocated; stream to/from stdio.
save: []string{"e2image", "-ra", "-p", dev, "-"},
restore: []string{"e2image", "-ra", "-p", "-", dev},
}
case "partclone":
pc := "partclone." + partcloneSuffix(fsType)
return &fsCloner{
name: pc,
save: []string{pc, "-c", "-s", dev, "-O", "-", "-L", "/dev/null"},
restore: []string{"partclone.restore", "-s", "-", "-O", dev, "-L", "/dev/null"},
}
}
return nil
}
func partcloneSuffix(fsType string) string {
switch fsType {
case "ext2", "ext3", "ext4":
return "extfs"
case "vfat", "fat", "fat12", "fat16", "fat32", "msdos":
return "fat"
case "ntfs":
return "ntfs"
default:
return fsType // exfat, xfs, btrfs, f2fs, hfsplus, ...
}
}
// chooseCloneMethod decides how a partition's data is copied.
//
// "raw" -> the block-diff engine over an offset window (also the
// re-run-friendly path; used for swap, unknown fs, --raw)
// "fs-image" -> stream a filesystem image with a standard tool
// "file-level" -> mkfs on the target + rsync
func chooseCloneMethod(p Partition, tools map[string]bool, forceRaw, forceFile map[int]bool, fileAuto bool) (method, tool string) {
if forceRaw[p.Num] {
return "raw", ""
}
if forceFile[p.Num] {
return "file-level", ""
}
if p.isBIOSBoot() {
return "raw", "" // tiny, and holds GRUB core - always verbatim
}
switch p.FSType {
case "", "swap", "crypto_LUKS", "LVM2_member":
return "raw", ""
case "ntfs":
if tools["ntfsclone"] {
return "fs-image", "ntfsclone"
}
case "ext2", "ext3", "ext4":
if tools["partclone.extfs"] && tools["partclone.restore"] {
return "fs-image", "partclone"
}
if tools["e2image"] {
return "fs-image", "e2image"
}
case "vfat", "fat", "fat12", "fat16", "fat32", "msdos":
if tools["partclone.fat"] && tools["partclone.restore"] {
return "fs-image", "partclone"
}
case "exfat", "xfs", "btrfs", "f2fs", "hfsplus":
if tools["partclone."+partcloneSuffix(p.FSType)] && tools["partclone.restore"] {
return "fs-image", "partclone"
}
}
if fileAuto && p.FSType != "" && tools["rsync"] {
return "file-level", ""
}
return "raw", ""
}
// progressScanner reads a cloner's stderr line by line, pulls a percentage
// out of the tool's own progress chatter, and calls emit with an estimated
// byte count (fraction * sizeBytes). It swallows everything else.
var pctRe = regexp.MustCompile(`([0-9]{1,3}(?:\.[0-9]+)?)\s*%|([0-9]{1,3}(?:\.[0-9]+)?)\s*percent`)
func scanCloneProgress(r io.Reader, sizeBytes int64, emit func(bytesDone int64)) {
br := bufio.NewReader(r)
var buf []byte
flush := func() {
line := strings.TrimSpace(string(buf))
buf = buf[:0]
if line == "" {
return
}
m := pctRe.FindStringSubmatch(line)
if m == nil {
return
}
s := m[1]
if s == "" {
s = m[2]
}
if f, err := strconv.ParseFloat(s, 64); err == nil && f >= 0 && f <= 100 {
emit(int64(f / 100 * float64(sizeBytes)))
}
}
for {
c, err := br.ReadByte()
if err != nil {
flush()
return
}
if c == '\n' || c == '\r' {
flush()
continue
}
buf = append(buf, c)
if len(buf) > 4096 {
buf = buf[:0]
}
}
}
// preShrinkFS shrinks the filesystem on dev to (at least) toBytes in place.
// Used only on the source, only with --allow-shrink --yes. Best effort with a
// hard error if the resize tool fails.
func preShrinkFS(dev, fsType string, toBytes int64) error {
if toBytes <= 0 {
return nil
}
switch {
case isExtFS(fsType):
if out, err := runCmd("e2fsck", "-f", "-y", dev); err != nil {
return fmt.Errorf("e2fsck %s: %v: %s", dev, err, out)
}
kib := toBytes / 1024
if out, err := runCmd("resize2fs", dev, fmt.Sprintf("%dK", kib)); err != nil {
return fmt.Errorf("resize2fs %s %dK: %v: %s", dev, kib, err, out)
}
return nil
case fsType == "ntfs":
// ntfsresize prompts for confirmation on a real resize; feed it "y".
if out, err := runCmdStdin("y\n", "ntfsresize", "--force", "--size", strconv.FormatInt(toBytes, 10), dev); err != nil {
return fmt.Errorf("ntfsresize %s --size %d: %v: %s", dev, toBytes, err, out)
}
return nil
default:
return fmt.Errorf("don't know how to shrink a %s filesystem", fsType)
}
}

112
main.go
View File

@ -5,6 +5,7 @@ import (
"fmt" "fmt"
"os" "os"
"runtime" "runtime"
"strings"
) )
func main() { func main() {
@ -17,6 +18,8 @@ func main() {
switch os.Args[1] { switch os.Args[1] {
case "sync": case "sync":
err = cmdSync(os.Args[2:]) err = cmdSync(os.Args[2:])
case "clone-disk":
err = cmdCloneDisk(os.Args[2:])
case "agent": case "agent":
err = cmdAgent(os.Args[2:]) err = cmdAgent(os.Args[2:])
case "version", "--version": case "version", "--version":
@ -40,8 +43,9 @@ func usage() {
Usage: Usage:
clonetool sync --source LOC --dest LOC [options] clonetool sync --source LOC --dest LOC [options]
clonetool clone-disk --source LOC --dest LOC [options]
clonetool version clonetool version
clonetool agent --role {control|sink|source-stream} ... (internal, spawned automatically) clonetool agent --role {control|sink|source-stream|fs-send|fs-recv} ... (internal, spawned automatically)
LOC is either a local path, or [user@]host:path for a path reached over SSH. LOC is either a local path, or [user@]host:path for a path reached over SSH.
Source, destination, and the machine running "sync" (the manager) may all be Source, destination, and the machine running "sync" (the manager) may all be
@ -51,6 +55,21 @@ a single block itself.
clonetool keeps no state between runs: every sync re-reads and re-hashes both clonetool keeps no state between runs: every sync re-reads and re-hashes both
the source and the destination and transfers only the blocks that differ. the source and the destination and transfers only the blocks that differ.
Options for clone-disk (whole-disk: boot record + partition table + per-filesystem data):
--parts LIST only clone these partition numbers (comma-separated; default all)
--raw LIST force a raw block clone for these partitions
--file-level LIST mkfs + rsync these partitions instead of a filesystem image
--file-level-auto use file-level for filesystem types with no image cloner
--allow-shrink permit shrinking trailing partitions to fit a smaller target
(resizes the SOURCE filesystem in place before imaging)
--no-shrink never shrink; fail instead if the target is too small
--new-ids randomize the GPT disk GUID / MBR signature on the target
--reinstall-bootloader after copy, run grub-install / grub-mkconfig on the target (Linux)
--vss Windows source: take a Volume Shadow Copy per NTFS volume (default on)
--image-size SIZE file target: image size (default = enough for the layout)
(also accepts --block-size --job --yes --sudo --deploy --ssh --ssh-opt --remote-bin
--connect-timeout --manager-host, same meaning as sync)
Options for sync: Options for sync:
--block-size SIZE block size, e.g. 4M (default 4M) --block-size SIZE block size, e.g. 4M (default 4M)
--job NAME optional label shown in progress/log output --job NAME optional label shown in progress/log output
@ -116,6 +135,97 @@ func cmdSync(args []string) error {
}) })
} }
func parseIntList(s string) ([]int, error) {
if strings.TrimSpace(s) == "" {
return nil, nil
}
var out []int
for _, f := range strings.Split(s, ",") {
f = strings.TrimSpace(f)
if f == "" {
continue
}
var n int
if _, err := fmt.Sscanf(f, "%d", &n); err != nil || n <= 0 {
return nil, fmt.Errorf("invalid partition number %q", f)
}
out = append(out, n)
}
return out, nil
}
func cmdCloneDisk(args []string) error {
fs := flag.NewFlagSet("clone-disk", flag.ContinueOnError)
job := fs.String("job", "", "optional label for progress/log output")
source := fs.String("source", "", "source whole-disk location (required)")
dest := fs.String("dest", "", "destination whole-disk or image location (required)")
blockSizeStr := fs.String("block-size", "4M", "block size for raw/boot-region transfers, e.g. 4M")
yes := fs.Bool("yes", false, "don't prompt before shrinking an existing destination image")
sudoMode := fs.String("sudo", "auto", "device-access privilege escalation: auto|always|never")
deploy := fs.Bool("deploy", true, "copy this binary to remote hosts that lack it")
connectTimeout := fs.Int("connect-timeout", defaultConnectTimeoutSec, "ssh connect timeout (seconds)")
sshBin := fs.String("ssh", "ssh", "ssh binary")
remoteBin := fs.String("remote-bin", "clonetool", "clonetool path on remote hosts")
managerHost := fs.String("manager-host", "", "address peers use to reach this machine")
partsStr := fs.String("parts", "", "only clone these partition numbers (comma-separated)")
rawStr := fs.String("raw", "", "force raw block clone for these partition numbers")
fileLevelStr := fs.String("file-level", "", "mkfs + rsync these partition numbers")
fileAuto := fs.Bool("file-level-auto", false, "file-level for fs types with no image cloner")
allowShrink := fs.Bool("allow-shrink", false, "permit shrinking trailing partitions to fit a smaller target")
noShrink := fs.Bool("no-shrink", false, "never shrink; fail if the target is too small")
newIDs := fs.Bool("new-ids", false, "randomize the GPT disk GUID / MBR signature on the target")
reinstallBoot := fs.Bool("reinstall-bootloader", false, "run grub-install / grub-mkconfig on the target after copy")
vss := fs.Bool("vss", true, "Windows source: take a Volume Shadow Copy per NTFS volume")
imageSizeStr := fs.String("image-size", "", "file target: image size (default: enough for the layout)")
var sshOpts stringSlice
fs.Var(&sshOpts, "ssh-opt", `extra "-o OPT" passed to ssh (repeatable)`)
if err := fs.Parse(args); err != nil {
return err
}
if *source == "" || *dest == "" {
fs.Usage()
return fmt.Errorf("--source and --dest are required")
}
blockSize, err := parseSize(*blockSizeStr)
if err != nil {
return fmt.Errorf("--block-size: %w", err)
}
switch *sudoMode {
case "auto", "always", "never":
default:
return fmt.Errorf("--sudo: want auto|always|never, got %q", *sudoMode)
}
parts, err := parseIntList(*partsStr)
if err != nil {
return fmt.Errorf("--parts: %w", err)
}
raw, err := parseIntList(*rawStr)
if err != nil {
return fmt.Errorf("--raw: %w", err)
}
fileLevel, err := parseIntList(*fileLevelStr)
if err != nil {
return fmt.Errorf("--file-level: %w", err)
}
var imageSize int64
if *imageSizeStr != "" {
if imageSize, err = parseSize(*imageSizeStr); err != nil {
return fmt.Errorf("--image-size: %w", err)
}
}
return runCloneDisk(CloneDiskConfig{
SyncConfig: SyncConfig{
Job: *job, Source: *source, Dest: *dest, BlockSize: blockSize,
Yes: *yes, Sudo: *sudoMode, Deploy: *deploy, ConnectTimeoutSec: *connectTimeout,
SSHBin: *sshBin, SSHOpts: sshOpts, RemoteBin: *remoteBin, ManagerHost: *managerHost,
},
Parts: parts, Raw: raw, FileLevel: fileLevel, FileAuto: *fileAuto,
AllowShrink: *allowShrink, NoShrink: *noShrink, NewIDs: *newIDs,
ReinstallBoot: *reinstallBoot, VSS: *vss, ImageSize: imageSize,
})
}
func parseSize(s string) (int64, error) { func parseSize(s string) (int64, error) {
if s == "" { if s == "" {
return 0, fmt.Errorf("empty size") return 0, fmt.Errorf("empty size")

20
manager.go
View File

@ -297,6 +297,26 @@ func (p *progressPrinter) print(m CtrlMsg) {
formatCount(p.copied), formatCount(p.skipped), scan, mib) formatCount(p.copied), formatCount(p.skipped), scan, mib)
} }
// printBytes renders a byte-oriented status line for clone-disk's fs-image
// partition clones, where progress arrives as BytesCopied/BytesTotal rather
// than block counts.
func (p *progressPrinter) printBytes(m CtrlMsg) {
if m.Type != msgProgress {
return
}
p.active = true
done, total := m.BytesCopied, m.BytesTotal
if total <= 0 {
total = done
}
stage := m.Stage
if stage == "" {
stage = "fs-image"
}
fmt.Fprintf(os.Stderr, "\r %s %s %s / %s ",
stage, progressBar(done, total), humanBytes(done), humanBytes(total))
}
// finish ends the current status line with a newline so following output // finish ends the current status line with a newline so following output
// (and the shell prompt) starts clean. // (and the shell prompt) starts clean.
func (p *progressPrinter) finish() { func (p *progressPrinter) finish() {

215
plan.go Normal file
View File

@ -0,0 +1,215 @@
package main
import (
"fmt"
"strings"
)
// plannedPart is one partition's copy plan: where it lives on each side (in
// bytes) and how its data moves.
type plannedPart struct {
Num int
SrcStartB, SrcSizeB int64
DstStartB, DstSizeB int64
Method string // "raw" | "fs-image" | "file-level"
Tool string // fs-image tool family
FSType string
ShrinkToB int64 // >0: shrink the fs to this many bytes before imaging
}
type targetPlan struct {
Script string // sfdisk restore script ("" when the source has no table / Windows-native)
IsFile bool
ImageSize int64 // file target: truncate to this
Parts []plannedPart
BootRegions []Region
RootPart int
ESPPart int
UEFI bool
Notes []string
}
// bootOpts is the JSON blob passed to reinstall_boot.
type bootOpts struct {
RootPart int `json:"rootPart"` // 1-based partition number holding "/"
ESPPart int `json:"espPart"` // 1-based ESP partition number, 0 if BIOS-only
UEFI bool `json:"uefi"`
DiskPath string `json:"diskPath"` // whole-disk path grub-install targets
}
type planOpts struct {
Parts map[int]bool // empty = all
Raw map[int]bool
FileLevel map[int]bool
FileAuto bool
AllowShrink bool
NewIDs bool
ImageSize int64 // explicit file-target size, 0 = auto
}
const gptTailSectors = 33 // secondary GPT header + entries
// planTargetLayout turns a probed source layout + the target's nature/size
// into a concrete copy plan, applying the sizing rules:
//
// - device target: never grow; if everything fits, keep the layout and
// leave trailing space untouched; if the last partition(s) overflow,
// shrink them (filesystem + partition) from the last inward, or fail.
// - file target: size the image to hold the layout (or ImageSize).
func planTargetLayout(src *DiskLayout, isFile bool, destSize int64, o planOpts) (*targetPlan, error) {
sector := src.LogicalSector
if sector <= 0 {
sector = 512
}
parts := sortedParts(src.Partitions)
var sel []Partition
for _, p := range parts {
if len(o.Parts) == 0 || o.Parts[p.Num] {
sel = append(sel, p)
}
}
if len(sel) == 0 && src.Scheme != "raw" {
return nil, fmt.Errorf("no partitions selected")
}
plan := &targetPlan{IsFile: isFile, BootRegions: append([]Region(nil), src.BootRegions...)}
// With --new-ids on an MBR disk, keep the raw bootstrap copy clear of the
// 4-byte disk signature at offset 0x1B8 so sfdisk's freshly generated one
// survives (GPT regenerates its GUID in the header, which we never
// raw-copy, so no clamp is needed there).
if o.NewIDs && src.Scheme == "mbr" {
for i := range plan.BootRegions {
r := &plan.BootRegions[i]
if r.Offset == 0 && r.Length > 0x1B8 {
r.Length = 0x1B8
}
}
}
// Bytes the layout needs on disk = end of the last selected partition
// (+ secondary GPT for GPT disks).
lastEndB := int64(0)
for _, p := range sel {
if e := (p.Start + p.Size) * sector; e > lastEndB {
lastEndB = e
}
}
neededB := lastEndB
if src.Scheme == "gpt" {
neededB += gptTailSectors * sector
}
if src.Scheme == "raw" {
neededB = src.DiskSize
}
if isFile {
plan.ImageSize = o.ImageSize
if plan.ImageSize == 0 {
plan.ImageSize = roundUp(neededB+(1<<20), 1<<20)
}
destSize = plan.ImageSize
}
if destSize <= 0 {
return nil, fmt.Errorf("could not determine target size")
}
// --- shrink pass ----------------------------------------------------
sizeOverride := map[int]int64{}
if destSize < neededB {
short := neededB - destSize
for i := len(sel) - 1; i >= 0 && short > 0; i-- {
p := &sel[i]
curB := p.Size * sector
minB := p.FSMinBytes
shrinkable := minB > 0 && (isExtFS(p.FSType) || p.FSType == "ntfs")
if !shrinkable {
continue
}
minB = roundUp(minB+(16<<20), sector) // 16 MiB slack
if minB >= curB {
continue
}
reduce := curB - minB
if reduce > short {
reduce = roundUp(short, sector)
}
newB := curB - reduce
sizeOverride[p.Num] = newB / sector
plan.Notes = append(plan.Notes,
fmt.Sprintf("partition p%d (%s) shrinks %s -> %s to fit the target",
p.Num, p.FSType, humanBytes(curB), humanBytes(newB)))
short -= reduce
}
if short > 0 {
return nil, fmt.Errorf(
"target (%s) is smaller than the source layout needs (%s); the trailing partition(s) "+
"cannot shrink to make up the missing %s; use a larger target",
humanBytes(destSize), humanBytes(neededB), humanBytes(short))
}
if !o.AllowShrink {
var names []string
for n := range sizeOverride {
names = append(names, fmt.Sprintf("p%d", n))
}
return nil, fmt.Errorf(
"target is smaller than the source; partition(s) %s would have to be shrunk. "+
"Re-run with --allow-shrink (this resizes the SOURCE filesystem in place before imaging) "+
"or use --no-shrink off / a larger target",
strings.Join(names, ", "))
}
}
// --- partition-table script --------------------------------------
if src.Scheme != "raw" && strings.TrimSpace(src.SfdiskDump) != "" {
plan.Script = src.sfdiskRestoreScript(o.NewIDs, sizeOverride)
}
// --- per-partition method --------------------------------------
for _, p := range sel {
pp := plannedPart{
Num: p.Num,
SrcStartB: p.Start * sector,
SrcSizeB: p.Size * sector,
DstStartB: p.Start * sector,
DstSizeB: p.Size * sector,
FSType: p.FSType,
}
if ov, ok := sizeOverride[p.Num]; ok {
pp.DstSizeB = ov * sector
pp.ShrinkToB = ov * sector
}
method, tool := chooseCloneMethod(p, src.Tools, o.Raw, o.FileLevel, o.FileAuto)
pp.Method, pp.Tool = method, tool
if pp.ShrinkToB > 0 && method != "fs-image" {
return nil, fmt.Errorf(
"partition p%d (%s) must shrink to fit but no image cloner is available for it; "+
"install ntfsclone / partclone or use a larger target", p.Num, orDash(p.FSType))
}
plan.Parts = append(plan.Parts, pp)
}
// --- boot roles ------------------------------------------------
plan.RootPart, plan.ESPPart = pickBootParts(sel)
plan.UEFI = plan.ESPPart != 0
return plan, nil
}
func isExtFS(t string) bool { return t == "ext2" || t == "ext3" || t == "ext4" }
// pickBootParts guesses the "/" partition (largest Linux fs) and the ESP.
func pickBootParts(sel []Partition) (root, esp int) {
var bestSize int64
for _, p := range sel {
if p.isESP() && esp == 0 {
esp = p.Num
}
switch p.FSType {
case "ext2", "ext3", "ext4", "btrfs", "xfs":
if sz := p.Size; sz > bestSize {
bestSize, root = sz, p.Num
}
}
}
return root, esp
}

146
plan_test.go Normal file
View File

@ -0,0 +1,146 @@
package main
import "testing"
// mkLayout builds a GPT layout: ESP (vfat) + root (ext4) + data (ntfs).
func mkLayout(diskBytes int64) *DiskLayout {
d := &DiskLayout{
DiskPath: "/dev/src", DiskSize: diskBytes, LogicalSector: 512,
Scheme: "gpt", Label: "gpt", LabelID: "GUID",
SfdiskDump: gptDump, // any non-empty dump so a script is produced
Tools: map[string]bool{
"sfdisk": true, "ntfsclone": true,
"partclone.extfs": true, "partclone.restore": true, "e2image": true,
},
Partitions: []Partition{
{Num: 1, Start: 2048, Size: 204800, Type: gptESP, FSType: "vfat"}, // 100 MiB
{Num: 2, Start: 206848, Size: 10 * 2048 * 1024, FSType: "ext4", FSMinBytes: 2 << 30}, // 10 GiB, min 2 GiB
{Num: 3, Start: 206848 + 10*2048*1024, Size: 10 * 2048 * 1024, FSType: "ntfs", FSMinBytes: 3 << 30}, // 10 GiB, min 3 GiB
},
BootRegions: []Region{{Offset: 0, Length: 446, Note: "MBR bootstrap"}},
}
return d
}
func lastEndBytes(d *DiskLayout) int64 {
var e int64
for _, p := range d.Partitions {
if x := (p.Start + p.Size) * d.LogicalSector; x > e {
e = x
}
}
return e + gptTailSectors*d.LogicalSector
}
func TestPlanFitsDeviceKeepsLayout(t *testing.T) {
d := mkLayout(40 << 30)
plan, err := planTargetLayout(d, false, 40<<30, planOpts{})
if err != nil {
t.Fatal(err)
}
if len(plan.Parts) != 3 {
t.Fatalf("parts = %d", len(plan.Parts))
}
for _, p := range plan.Parts {
if p.SrcSizeB != p.DstSizeB || p.ShrinkToB != 0 {
t.Fatalf("p%d resized unexpectedly: %+v", p.Num, p)
}
if p.SrcStartB != p.DstStartB {
t.Fatalf("p%d start moved", p.Num)
}
}
if plan.Parts[0].Method != "raw" { // vfat, no partclone.fat in tool set
t.Fatalf("p1 method = %s", plan.Parts[0].Method)
}
if plan.Parts[1].Method != "fs-image" || plan.Parts[1].Tool != "partclone" {
t.Fatalf("p2 method/tool = %s/%s", plan.Parts[1].Method, plan.Parts[1].Tool)
}
if plan.Parts[2].Method != "fs-image" || plan.Parts[2].Tool != "ntfsclone" {
t.Fatalf("p3 method/tool = %s/%s", plan.Parts[2].Method, plan.Parts[2].Tool)
}
if plan.ESPPart != 1 || plan.RootPart != 2 || !plan.UEFI {
t.Fatalf("boot roles: esp=%d root=%d uefi=%v", plan.ESPPart, plan.RootPart, plan.UEFI)
}
}
func TestPlanTrailingFreeSpaceOK(t *testing.T) {
d := mkLayout(60 << 30)
// target smaller than the *disk* but larger than what the layout needs
need := lastEndBytes(d)
if _, err := planTargetLayout(d, false, need+1<<20, planOpts{}); err != nil {
t.Fatalf("should fit into %d (need %d): %v", need+1<<20, need, err)
}
}
func TestPlanNeedsShrinkRequiresFlag(t *testing.T) {
d := mkLayout(40 << 30)
need := lastEndBytes(d)
small := need - (4 << 30) // 4 GiB short; ntfs (min 3 GiB) can give it up
if _, err := planTargetLayout(d, false, small, planOpts{}); err == nil {
t.Fatalf("expected error without --allow-shrink")
}
plan, err := planTargetLayout(d, false, small, planOpts{AllowShrink: true})
if err != nil {
t.Fatalf("with --allow-shrink: %v", err)
}
p3 := plan.Parts[2]
if p3.ShrinkToB == 0 || p3.ShrinkToB >= p3.SrcSizeB {
t.Fatalf("p3 should shrink: %+v", p3)
}
if p3.Method != "fs-image" {
t.Fatalf("shrunk partition must be fs-image, got %s", p3.Method)
}
}
func TestPlanCannotFit(t *testing.T) {
d := mkLayout(40 << 30)
// absurdly small: even shrinking ntfs+ext to their minimums can't help
if _, err := planTargetLayout(d, false, 1<<30, planOpts{AllowShrink: true}); err == nil {
t.Fatalf("expected cannot-fit error")
}
}
func TestPlanFileTargetSizing(t *testing.T) {
d := mkLayout(40 << 30)
plan, err := planTargetLayout(d, true, 0, planOpts{})
if err != nil {
t.Fatal(err)
}
need := lastEndBytes(d)
if plan.ImageSize < need || plan.ImageSize > need+(2<<20) {
t.Fatalf("image size %d not ~%d", plan.ImageSize, need)
}
if plan.Script == "" {
t.Fatalf("expected a partition-table script for a file target")
}
}
func TestPlanNewIDsScript(t *testing.T) {
d := mkLayout(40 << 30)
plan, err := planTargetLayout(d, true, 0, planOpts{NewIDs: true})
if err != nil {
t.Fatal(err)
}
if plan.Script == "" || containsAny(plan.Script, "label-id:", "uuid=") {
t.Fatalf("--new-ids script still has ids:\n%s", plan.Script)
}
}
func containsAny(s string, subs ...string) bool {
for _, x := range subs {
if len(x) > 0 && indexOf(s, x) >= 0 {
return true
}
}
return false
}
func indexOf(s, sub string) int {
for i := 0; i+len(sub) <= len(s); i++ {
if s[i:i+len(sub)] == sub {
return i
}
}
return -1
}

27
syncside.go
View File

@ -81,12 +81,15 @@ type blockHash struct {
hash [32]byte hash [32]byte
} }
// streamHashBlocks reads f in blockSize-byte blocks up to size, hashing each // streamHashBlocks reads f in blockSize-byte blocks over the window
// one and handing it to onHash the moment it is computed (this is what lets // [base, base+size), hashing each one and handing it to onHash the moment it
// the peer start comparing before the whole side has been scanned). It keeps // is computed (this is what lets the peer start comparing before the whole
// no hash state of its own. onProgress, if non-nil, is called with // side has been scanned). It keeps no hash state of its own. onProgress, if
// (blocksHashed, totalBlocks) before the first block and after each one. // non-nil, is called with (blocksHashed, totalBlocks) before the first block
func streamHashBlocks(f *os.File, size, blockSize, align int64, onHash func(bh blockHash) error, onProgress func(done, total int64)) error { // and after each one. base is 0 for a whole-file sync; clone-disk passes a
// non-zero base to fingerprint just a boot region / offset-addressed
// partition within a larger handle.
func streamHashBlocks(f *os.File, base, size, blockSize, align int64, onHash func(bh blockHash) error, onProgress func(done, total int64)) error {
if err := checkBlockAlign(blockSize, align); err != nil { if err := checkBlockAlign(blockSize, align); err != nil {
return err return err
} }
@ -96,7 +99,7 @@ func streamHashBlocks(f *os.File, size, blockSize, align int64, onHash func(bh b
onProgress(0, blockCount) onProgress(0, blockCount)
} }
for i := int64(0); i < blockCount; i++ { for i := int64(0); i < blockCount; i++ {
n, err := readBlockAt(f, buf, i*blockSize, size, align) n, err := readBlockAt(f, buf, base+i*blockSize, base+size, align)
if err != nil { if err != nil {
return fmt.Errorf("hash %s at block %d: %w", f.Name(), i, err) return fmt.Errorf("hash %s at block %d: %w", f.Name(), i, err)
} }
@ -130,7 +133,8 @@ func scanProgressEmitter(out *FrameWriter) func(done, total int64) {
// never read twice. // never read twice.
type sourceLoopParams struct { type sourceLoopParams struct {
File *os.File // already opened for reading by the caller File *os.File // already opened for reading by the caller
Size int64 Base int64 // byte offset the window starts at (0 for a whole-file sync)
Size int64 // window length in bytes
BlockSize int64 BlockSize int64
Align int64 Align int64
Hashes <-chan blockHash Hashes <-chan blockHash
@ -151,8 +155,8 @@ func runSourceLoop(p sourceLoopParams) error {
f := p.File f := p.File
buf := make([]byte, p.BlockSize) buf := make([]byte, p.BlockSize)
for bh := range p.Hashes { for bh := range p.Hashes {
offset := int64(bh.index) * p.BlockSize offset := p.Base + int64(bh.index)*p.BlockSize
n, err := readBlockAt(f, buf, offset, p.Size, p.Align) n, err := readBlockAt(f, buf, offset, p.Base+p.Size, p.Align)
if err != nil { if err != nil {
return fmt.Errorf("read %s at block %d: %w", f.Name(), bh.index, err) return fmt.Errorf("read %s at block %d: %w", f.Name(), bh.index, err)
} }
@ -181,6 +185,7 @@ func runSourceLoop(p sourceLoopParams) error {
// same process, before OnWritten is called). // same process, before OnWritten is called).
type destLoopParams struct { type destLoopParams struct {
File *os.File // already opened for read/write by the caller File *os.File // already opened for read/write by the caller
Base int64 // byte offset the window starts at (0 for a whole-file sync)
BlockSize int64 BlockSize int64
Align int64 // sector alignment for a raw disk handle, else 0/1 Align int64 // sector alignment for a raw disk handle, else 0/1
In *FrameReader In *FrameReader
@ -212,7 +217,7 @@ func runDestLoop(p destLoopParams) error {
} }
return fmt.Errorf("block %d: hash mismatch after transfer", index) return fmt.Errorf("block %d: hash mismatch after transfer", index)
} }
if err := writeBlockAt(f, block, int64(index)*p.BlockSize, p.Align); err != nil { if err := writeBlockAt(f, block, p.Base+int64(index)*p.BlockSize, p.Align); err != nil {
if p.AckOut != nil { if p.AckOut != nil {
_ = p.AckOut.WriteFrame(frameErr, encodeErrFrame(index, err.Error())) _ = p.AckOut.WriteFrame(frameErr, encodeErrFrame(index, err.Error()))
} }

16
util.go
View File

@ -2,9 +2,25 @@ package main
import ( import (
"fmt" "fmt"
"os/exec"
"strings"
"sync" "sync"
) )
// runCmd runs name with args, returning trimmed combined output.
func runCmd(name string, args ...string) (string, error) {
out, err := exec.Command(name, args...).CombinedOutput()
return strings.TrimSpace(string(out)), err
}
// runCmdStdin is runCmd with a fixed stdin string (for tools that prompt).
func runCmdStdin(stdin, name string, args ...string) (string, error) {
c := exec.Command(name, args...)
c.Stdin = strings.NewReader(stdin)
out, err := c.CombinedOutput()
return strings.TrimSpace(string(out)), err
}
// limitedBuffer keeps only the last maxLen bytes written to it — used to // limitedBuffer keeps only the last maxLen bytes written to it — used to
// capture a bounded tail of a subprocess's stderr for error messages // capture a bounded tail of a subprocess's stderr for error messages
// without risking unbounded memory growth from a noisy remote command. // without risking unbounded memory growth from a noisy remote command.