Refactor panes and filesystem; replace FUSE with 9P

Consolidate pane, layout, memory and host code. Serve 9P by default over Unix sockets, with runtime mounts and optional TCP/QUIC transports. Remove FUSE and obsolete proof-of-concept examples.

Fix highlighting and terminal-history performance, expand differential and stress-test infrastructure, sort navigation results while preserving the next occurrence, add syntax-colored Braille minimaps, remove SPC-k, and document 9P interaction as a repository skill.

1 files changed, 148 insertions, 0 deletions

diff --git a/test/ninep.py b/test/ninep.py
new file mode 100644
index 00000000..b128cc8a
--- /dev/null
+++ b/test/ninep.py
@@ -0,0 +1,148 @@
+#!/usr/bin/env python3
+import json
+import os
+import socket
+import struct
+
+
+def string(value):
+    data = value.encode() if isinstance(value, str) else value
+    return struct.pack('<H', len(data)) + data
+
+
+class Client:
+    def __init__(self, address, timeout=5, msize=8192):
+        tcp = isinstance(address, tuple)
+        family = (socket.AF_INET6 if ':' in address[0] else socket.AF_INET) if tcp else socket.AF_UNIX
+        self.socket = socket.socket(family)
+        self.socket.settimeout(timeout)
+        if tcp:
+            self.socket.setsockopt(socket.IPPROTO_TCP, socket.TCP_NODELAY, 1)
+        self.tag = 0
+        self.fid = 1
+        self.msize = msize
+        try:
+            self.socket.connect(address if tcp else os.fspath(address))
+            reply = self.rpc(100, struct.pack('<I', self.msize) + string('9P2000'), tag=65535)
+            self.msize = min(self.msize, struct.unpack_from('<I', reply)[0])
+            if self.msize < 256 or reply[4:] != string('9P2000'):
+                raise OSError('unsupported 9P version or message size')
+            attached = self.rpc(104, struct.pack('<II', 1, 0xffffffff) + string('pardes') + string(''))
+            if len(attached) != 13:
+                raise OSError('invalid attach qid')
+        except BaseException:
+            self.socket.close()
+            raise
+
+    def __enter__(self):
+        return self
+
+    def __exit__(self, *args):
+        self.socket.close()
+
+    def receive(self, count):
+        data = bytearray()
+        while len(data) < count:
+            chunk = self.socket.recv(count - len(data))
+            if not chunk:
+                raise EOFError('9P peer closed the connection')
+            data.extend(chunk)
+        return bytes(data)
+
+    def rpc(self, kind, payload, tag=None):
+        if tag is None:
+            self.tag = (self.tag + 1) % 65535
+            tag = self.tag
+        packet = struct.pack('<IBH', 7 + len(payload), kind, tag) + payload
+        if len(packet) > self.msize:
+            raise ValueError('request exceeds negotiated message size')
+        self.socket.sendall(packet)
+        size, answer, received_tag = struct.unpack('<IBH', self.receive(7))
+        if not 7 <= size <= self.msize or received_tag != tag:
+            raise OSError('invalid 9P reply header')
+        reply = self.receive(size - 7)
+        if answer == 107:
+            length = struct.unpack_from('<H', reply)[0]
+            raise OSError(reply[2:2 + length].decode(errors='replace'))
+        if answer != kind + 1:
+            raise OSError(f'expected reply {kind + 1}, received {answer}')
+        return reply
+
+    def open(self, path, mode=0):
+        names = [part for part in os.fspath(path).split('/') if part]
+        self.fid += 1
+        fid = self.fid
+        oldfid = 1
+        try:
+            for start in range(0, max(1, len(names)), 16):
+                part = names[start:start + 16]
+                reply = self.rpc(110, struct.pack('<IIH', oldfid, fid, len(part)) +
+                                 b''.join(string(name) for name in part))
+                walked = struct.unpack_from('<H', reply)[0]
+                if len(reply) != 2 + 13 * walked:
+                    raise OSError('invalid walk qids')
+                if walked != len(part):
+                    raise FileNotFoundError(path)
+                oldfid = fid
+            if len(self.rpc(112, struct.pack('<IB', fid, mode))) != 17:
+                raise OSError('invalid open reply')
+            return fid
+        except BaseException:
+            try:
+                self.close(fid)
+            except OSError:
+                pass
+            raise
+
+    def close(self, fid):
+        self.rpc(120, struct.pack('<I', fid))
+
+    def read_fid(self, fid, offset=0, count=None):
+        count = min(count if count is not None else self.msize - 11, self.msize - 11)
+        reply = self.rpc(116, struct.pack('<IQI', fid, offset, count))
+        size = struct.unpack_from('<I', reply)[0]
+        if size != len(reply) - 4 or size > count:
+            raise OSError('invalid 9P read length')
+        return reply[4:]
+
+    def read(self, path):
+        fid = self.open(path)
+        try:
+            data = bytearray()
+            while chunk := self.read_fid(fid, len(data)):
+                data.extend(chunk)
+            return bytes(data)
+        finally:
+            self.close(fid)
+
+    def screen(self):
+        return json.loads(self.read('/self/screen'))
+
+    def write(self, path, data, truncate=False):
+        fid = self.open(path, 1 | (16 if truncate else 0))
+        try:
+            offset = 0
+            while offset < len(data):
+                chunk = data[offset:offset + self.msize - 23]
+                reply = self.rpc(118, struct.pack('<IQI', fid, offset, len(chunk)) + chunk)
+                count = struct.unpack('<I', reply)[0]
+                if not 0 < count <= len(chunk):
+                    raise OSError('invalid 9P write length')
+                offset += count
+        finally:
+            self.close(fid)
+
+    def list(self, path='/'):
+        data = self.read(path)
+        names = []
+        offset = 0
+        while offset < len(data):
+            size = struct.unpack_from('<H', data, offset)[0]
+            if size < 47 or offset + size + 2 > len(data):
+                raise OSError('invalid 9P directory entry')
+            length = struct.unpack_from('<H', data, offset + 41)[0]
+            if 43 + length > size + 2:
+                raise OSError('invalid directory name length')
+            names.append(data[offset + 43:offset + 43 + length].decode())
+            offset += size + 2
+        return names