add http/httphi (#171)

* add http/httphi

* begin adding httphi tests

* claude found neat bugs

* add low level Handle function and more tests

* more tests, run go generate

* add Hijacker-like functionality

* improve locking and acquisition of Exchanges in reconfiguring

* several bugfixes, add internal.IntLen, round up http-linux example with new router API

* small nit

* add benchmarks

* add query handling

* remove ForEach pattern, allocates in TinyGo

* massive documentation push and code reordering in files

* Router.Handle returns error after being torn down

* run go fix

* rework Mux interface to receive a string request path

* add MethodFrom

* minor doc nit

* fail on incomplete staging

* add raw buffer access

* add streaming API distinct from Exchange

* begin adding multipart form logic

* finish rounding up multipart form parsing

* remove status type

* first Multipart approach

* begin adding readMultiPart

* add Exchange.ReadMultiparts reimagining of clanker slop

* ai insists with backoffs

* simplify clanker slop

* apply go fix

* add a pattern argument to Mux

* explicit header key/value alloc and add ExchangeConfig

* fix tests after excplicit header alloc change

* fix examples

* run go fix

* expose rawsock as experimental package (will use for external benchmarks)

* remove backoff from form parsing

* @MDr164 suggestions get potential fixes

* apply go fix

* add examples

* add README.md

* fix rawsock tinygo implementation

* apply @MDr164 various fixes

* update documentation on ContentLength methods and fix bug in Form reset on empty body

* fix tests

* add fuzz tests

* run go fix

* io.ErrNoProgress on parsing form spin

* run go fix

* remove backoff assumption from Router

* httphi.Handle rejects unsupported protocols

* go format router.go

* add kvbuffer

* rewrite Cookie with KVBuffer

* mid refactor of KVBuffer into Header

* work on KVBuffer exhausted semantics

* add Go's ServeMux Request.PathValue access semantics to Exchange, Mux and MuxSlice

* add PathValue example

* document all the things; improve req Query semantics; add Form.EnableBufferGrowth

* unexport kvBuffer

* add Exchange.PathValueAppend

* use stdlib in example instead of rawsock

* remove rawsock from http example

* add darwin arch rawsock

* fix example

* rename Router.TeardownGoroutines to Shutdown matching http.Server.Shutdown

* rename types and identifiers

* @MDr164 Content-Type and Transfer-Encoding bug catches

x/rawsock/doc.go

@@ -0,0 +1,11 @@
+// Package rawsock listens and reads over Linux sockets through syscalls
+// directly, without the net package. It exists so a server can be measured
+// without net.TCPConn, its netFD and its poller on the path.
+//
+// [Conn] and [Listener] implement [net.Conn] and [net.Listener] the way
+// TinyGo's net package does: a connection is its file descriptor plus its
+// addresses, deadlines live on the struct and are handed to the socket, and
+// nothing sits between a Read and the syscall. A server written against these
+// interfaces runs unchanged over the net package, over this package and over
+// TinyGo's netdev.
+package rawsock

x/rawsock/rawsock_darwin.go

@@ -0,0 +1,7 @@
+//go:build !tinygo && darwin
+
+package rawsock
+
+import "syscall"
+
+const sysaccept = syscall.SYS_ACCEPT

x/rawsock/rawsock_linux.go

@@ -0,0 +1,7 @@
+//go:build !tinygo && linux
+
+package rawsock
+
+import "syscall"
+
+const sysaccept = syscall.SYS_ACCEPT4

x/rawsock/rawsock_other.go

@@ -0,0 +1,49 @@
+//go:build tinygo || (!linux && !darwin)
+
+package rawsock
+
+import (
+	"errors"
+	"net"
+	"net/netip"
+	"time"
+)
+
+var (
+	_ net.Conn     = (*Conn)(nil)
+	_ net.Listener = (*Listener)(nil)
+)
+
+// Addr is a socket address implementing [net.Addr].
+type Addr netip.AddrPort
+
+func (a Addr) Network() string          { return "tcp" }
+func (a Addr) String() string           { return netip.AddrPort(a).String() }
+func (a Addr) AddrPort() netip.AddrPort { return netip.AddrPort(a) }
+
+// Conn is an accepted connection. Unsupported on this platform.
+type Conn struct{}
+
+func (c *Conn) Read(b []byte) (int, error)  { return 0, errors.ErrUnsupported }
+func (c *Conn) Write(b []byte) (int, error) { return 0, errors.ErrUnsupported }
+func (c *Conn) Close() error                { return errors.ErrUnsupported }
+func (c *Conn) LocalAddr() net.Addr         { return Addr{} }
+func (c *Conn) RemoteAddr() net.Addr        { return Addr{} }
+
+func (c *Conn) SetDeadline(t time.Time) error               { return errors.ErrUnsupported }
+func (c *Conn) SetReadDeadline(t time.Time) error           { return errors.ErrUnsupported }
+func (c *Conn) SetWriteDeadline(t time.Time) error          { return errors.ErrUnsupported }
+func (c *Conn) SetReadTimeout(timeout time.Duration) error  { return errors.ErrUnsupported }
+func (c *Conn) SetWriteTimeout(timeout time.Duration) error { return errors.ErrUnsupported }
+
+// Listener is a listening socket. Unsupported on this platform.
+type Listener struct{}
+
+// Listen is unsupported on this platform.
+func (l *Listener) Listen(port uint16) error { return errors.ErrUnsupported }
+
+func (l *Listener) Accept() (net.Conn, error)   { return nil, errors.ErrUnsupported }
+func (l *Listener) AcceptConn(conn *Conn) error { return errors.ErrUnsupported }
+func (l *Listener) Addr() net.Addr              { return Addr{} }
+func (l *Listener) Port() uint16                { return 0 }
+func (l *Listener) Close() error                { return errors.ErrUnsupported }

x/rawsock/rawsock_unix.go

@@ -0,0 +1,244 @@
+//go:build !tinygo && (linux || darwin)
+
+package rawsock
+
+import (
+	"net"
+	"net/netip"
+	"syscall"
+	"time"
+	"unsafe"
+)
+
+// The interfaces this package exists to satisfy: an http.Server and a heapless
+// router must both accept what Listen hands back.
+var (
+	_ net.Conn     = (*Conn)(nil)
+	_ net.Listener = (*Listener)(nil)
+)
+
+// Addr is a socket address. It implements [net.Addr] over a
+// [netip.AddrPort], which costs no allocation to carry around, unlike
+// [net.TCPAddr] and its IP slice.
+type Addr netip.AddrPort
+
+// Network returns "tcp".
+func (a Addr) Network() string { return "tcp" }
+
+// String returns the address in host:port form.
+func (a Addr) String() string { return netip.AddrPort(a).String() }
+
+// AddrPort returns the address as a [netip.AddrPort].
+func (a Addr) AddrPort() netip.AddrPort { return netip.AddrPort(a) }
+
+// Conn is an accepted TCP connection over a raw socket file descriptor. It
+// implements [net.Conn], so both an [net/http.Server] and a heapless router can
+// be handed the same connection.
+//
+// Deadlines are enforced by the socket itself through SO_RCVTIMEO and
+// SO_SNDTIMEO: a read that runs out of time fails with a [net.Error] that
+// reports Timeout, as callers of net.Conn expect.
+type Conn struct {
+	fd            int
+	local, remote Addr
+	readDeadline  time.Time
+	writeDeadline time.Time
+}
+
+// Read reads bytes from the connection into b.
+func (c *Conn) Read(b []byte) (int, error) {
+	if len(b) == 0 {
+		return 0, nil
+	}
+	n, err := syscall.Read(c.fd, b)
+	if err != nil {
+		return 0, c.opError("read", err)
+	}
+	if n == 0 {
+		return 0, syscall.ECONNRESET // Peer closed.
+	}
+	return n, nil
+}
+
+// Write writes b to the connection, looping until all bytes are sent.
+func (c *Conn) Write(b []byte) (int, error) {
+	total := 0
+	for total < len(b) {
+		n, err := syscall.Write(c.fd, b[total:])
+		if err != nil {
+			return total, c.opError("write", err)
+		}
+		total += n
+	}
+	return total, nil
+}
+
+// Close closes the underlying file descriptor.
+func (c *Conn) Close() error {
+	return syscall.Close(c.fd)
+}
+
+// LocalAddr returns the address the connection was accepted on.
+func (c *Conn) LocalAddr() net.Addr { return c.local }
+
+// RemoteAddr returns the peer address of the connection.
+func (c *Conn) RemoteAddr() net.Addr { return c.remote }
+
+// SetDeadline sets both the read and write deadline. A zero time removes them.
+func (c *Conn) SetDeadline(t time.Time) error {
+	err := c.SetReadDeadline(t)
+	if err != nil {
+		return err
+	}
+	return c.SetWriteDeadline(t)
+}
+
+// SetReadDeadline makes reads after t fail with a timeout error. A zero time
+// lets reads block indefinitely.
+func (c *Conn) SetReadDeadline(t time.Time) error {
+	c.readDeadline = t
+	return c.SetReadTimeout(untilDeadline(t))
+}
+
+// SetWriteDeadline makes writes after t fail with a timeout error. A zero time
+// lets writes block indefinitely.
+func (c *Conn) SetWriteDeadline(t time.Time) error {
+	c.writeDeadline = t
+	return c.SetWriteTimeout(untilDeadline(t))
+}
+
+// SetReadTimeout limits how long a single Read waits for data before failing
+// with a timeout error. Zero blocks indefinitely. This is what stops a peer
+// that opens a connection and then stalls from holding a server worker: the
+// connection, not the HTTP handler, owns the idle policy.
+func (c *Conn) SetReadTimeout(timeout time.Duration) error {
+	return setSockTimeout(c.fd, syscall.SO_RCVTIMEO, timeout)
+}
+
+// SetWriteTimeout limits how long a single Write waits for the send buffer to
+// drain before failing with a timeout error. Zero blocks indefinitely.
+func (c *Conn) SetWriteTimeout(timeout time.Duration) error {
+	return setSockTimeout(c.fd, syscall.SO_SNDTIMEO, timeout)
+}
+
+// opError wraps a socket error the way the net package does, so that callers
+// which test for a timeout with [net.Error] see one. A deadline that has passed
+// surfaces from the kernel as EAGAIN, which on a blocking socket only ever
+// means the timeout fired.
+func (c *Conn) opError(op string, err error) error {
+	if err == syscall.EAGAIN || err == syscall.EWOULDBLOCK {
+		err = errTimeout{}
+	}
+	return &net.OpError{Op: op, Net: "tcp", Source: c.local, Addr: c.remote, Err: err}
+}
+
+// errTimeout is the error a read or write past its deadline fails with.
+type errTimeout struct{}
+
+func (errTimeout) Error() string   { return "i/o timeout" }
+func (errTimeout) Timeout() bool   { return true }
+func (errTimeout) Temporary() bool { return true }
+
+func untilDeadline(t time.Time) time.Duration {
+	if t.IsZero() {
+		return 0 // No deadline: block indefinitely.
+	}
+	remaining := time.Until(t)
+	if remaining <= 0 {
+		return time.Nanosecond // Already past: fail the next call, do not block.
+	}
+	return remaining
+}
+
+func setSockTimeout(fd, option int, timeout time.Duration) error {
+	tv := syscall.NsecToTimeval(int64(timeout))
+	return syscall.SetsockoptTimeval(fd, syscall.SOL_SOCKET, option, &tv)
+}
+
+// Listener is a listening TCP socket bound to a local port. It implements
+// [net.Listener].
+type Listener struct {
+	fd    int
+	local Addr
+}
+
+// Listen creates a listening TCP socket bound to port on all interfaces. A
+// zero port lets the kernel choose one, see [Listener.Addr].
+func (l *Listener) Listen(port uint16) error {
+	fd, err := syscall.Socket(syscall.AF_INET, syscall.SOCK_STREAM, syscall.IPPROTO_TCP)
+	if err != nil {
+		return err
+	}
+	// Allow quick rebind after restart.
+	if err = syscall.SetsockoptInt(fd, syscall.SOL_SOCKET, syscall.SO_REUSEADDR, 1); err != nil {
+		syscall.Close(fd)
+		return err
+	}
+	addr := &syscall.SockaddrInet4{Port: int(port)}
+	if err = syscall.Bind(fd, addr); err != nil {
+		syscall.Close(fd)
+		return err
+	}
+	if err = syscall.Listen(fd, syscall.SOMAXCONN); err != nil {
+		syscall.Close(fd)
+		return err
+	}
+	l.fd = fd
+	l.local = Addr{}
+	bound, err := syscall.Getsockname(fd)
+	if err != nil {
+		syscall.Close(fd)
+		return err
+	}
+	if sa4, ok := bound.(*syscall.SockaddrInet4); ok {
+		l.local = Addr(netip.AddrPortFrom(netip.AddrFrom4(sa4.Addr), uint16(sa4.Port)))
+	}
+	return nil
+}
+
+// Accept blocks until an incoming connection arrives and returns it. It
+// allocates the connection, as [net.Listener] requires. A server that keeps its
+// own connection storage should call [Listener.AcceptConn] instead.
+func (l *Listener) Accept() (net.Conn, error) {
+	conn := new(Conn)
+	err := l.AcceptConn(conn)
+	if err != nil {
+		return nil, err
+	}
+	return conn, nil
+}
+
+// AcceptConn blocks until an incoming connection arrives and stores it in conn,
+// reusing whatever conn already held. Nothing is allocated.
+//
+// The syscall is made by hand because [syscall.Accept] allocates the
+// [syscall.Sockaddr] it returns, one per accepted connection: the kernel is
+// given address storage this call owns instead, and the address is read out of
+// it into conn.
+func (l *Listener) AcceptConn(conn *Conn) error {
+	var rsa syscall.RawSockaddrAny
+	salen := uint32(unsafe.Sizeof(rsa))
+	nfd, _, errno := syscall.Syscall6(sysaccept, uintptr(l.fd),
+		uintptr(unsafe.Pointer(&rsa)), uintptr(unsafe.Pointer(&salen)), 0, 0, 0)
+	if errno != 0 {
+		return errno
+	}
+	*conn = Conn{fd: int(nfd), local: l.local}
+	if rsa.Addr.Family == syscall.AF_INET {
+		sa4 := (*syscall.RawSockaddrInet4)(unsafe.Pointer(&rsa))
+		// Port is in network byte order in the sockaddr the kernel filled.
+		port := uint16(sa4.Port<<8) | uint16(sa4.Port>>8)
+		conn.remote = Addr(netip.AddrPortFrom(netip.AddrFrom4(sa4.Addr), port))
+	}
+	return nil
+}
+
+// Addr returns the address the socket is bound to, which carries the port the
+// kernel picked when the listener was created with port zero.
+func (l *Listener) Addr() net.Addr { return l.local }
+
+// Port returns the port the socket is bound to.
+func (l *Listener) Port() uint16 { return l.local.AddrPort().Port() }
+
+// Close closes the listening socket.
+func (l *Listener) Close() error { return syscall.Close(l.fd) }

x/xnet/xnet_fuzz_test.go

@@ -32,7 +32,7 @@ func FuzzStackPacketHTTP(f *testing.F) {
 	}
 	hdr.SetMethod("GET")
 	hdr.SetProtocol("HTTP/1.1")
-	hdr.SetRequestURI("/")
+	hdr.SetRequestTarget("/")
 	data := hdr.AppendHeaders(nil)
 
 	pktnum := 0