http2: port upstream inbound flow control fixes to stop window leaks

alpn_test.go

@@ -15,8 +15,8 @@ import (
 
 	tls "github.com/bogdanfinn/utls"
 
-	. "github.com/bogdanfinn/fhttp"
-	"github.com/bogdanfinn/fhttp/httptest"
+	. "github.com/kernel/fhttp"
+	"github.com/kernel/fhttp/httptest"
 )
 
 func TestNextProtoUpgrade(t *testing.T) {

cgi/child.go

@@ -20,7 +20,7 @@ import (
 
 	tls "github.com/bogdanfinn/utls"
 
-	http "github.com/bogdanfinn/fhttp"
+	http "github.com/kernel/fhttp"
 )
 
 // Request returns the HTTP request as represented in the current

cgi/child_test.go

@@ -13,7 +13,7 @@ import (
 	"strings"
 	"testing"
 
-	http "github.com/bogdanfinn/fhttp"
+	http "github.com/kernel/fhttp"
 )
 
 func TestRequest(t *testing.T) {

cgi/host.go

@@ -29,7 +29,7 @@ import (
 	"strconv"
 	"strings"
 
-	http "github.com/bogdanfinn/fhttp"
+	http "github.com/kernel/fhttp"
 
 	"golang.org/x/net/http/httpguts"
 )

cgi/host_test.go

@@ -22,8 +22,8 @@ import (
 	"testing"
 	"time"
 
-	http "github.com/bogdanfinn/fhttp"
-	"github.com/bogdanfinn/fhttp/httptest"
+	http "github.com/kernel/fhttp"
+	"github.com/kernel/fhttp/httptest"
 )
 
 func newRequest(httpreq string) *http.Request {

cgi/integration_test.go

@@ -19,9 +19,9 @@ import (
 	"testing"
 	"time"
 
-	http "github.com/bogdanfinn/fhttp"
-	"github.com/bogdanfinn/fhttp/httptest"
-	"github.com/bogdanfinn/fhttp/internal/testenv"
+	http "github.com/kernel/fhttp"
+	"github.com/kernel/fhttp/httptest"
+	"github.com/kernel/fhttp/internal/testenv"
 )
 
 // This test is a CGI host (testing host.go) that runs its own binary

client_test.go

@@ -26,9 +26,9 @@ import (
 
 	tls "github.com/bogdanfinn/utls"
 
-	. "github.com/bogdanfinn/fhttp"
-	"github.com/bogdanfinn/fhttp/cookiejar"
-	"github.com/bogdanfinn/fhttp/httptest"
+	. "github.com/kernel/fhttp"
+	"github.com/kernel/fhttp/cookiejar"
+	"github.com/kernel/fhttp/httptest"
 )
 
 var robotsTxtHandler = HandlerFunc(func(w ResponseWriter, r *Request) {

clientserver_test.go

@@ -29,9 +29,9 @@ import (
 
 	tls "github.com/bogdanfinn/utls"
 
-	. "github.com/bogdanfinn/fhttp"
-	"github.com/bogdanfinn/fhttp/httptest"
-	"github.com/bogdanfinn/fhttp/httputil"
+	. "github.com/kernel/fhttp"
+	"github.com/kernel/fhttp/httptest"
+	"github.com/kernel/fhttp/httputil"
 )
 
 type clientServerTest struct {

cookiejar/dummy_publicsuffix_test.go

@@ -4,7 +4,7 @@
 
 package cookiejar_test
 
-import "github.com/bogdanfinn/fhttp/cookiejar"
+import "github.com/kernel/fhttp/cookiejar"
 
 type dummypsl struct {
 	List cookiejar.PublicSuffixList

cookiejar/example_test.go

@@ -9,9 +9,9 @@ import (
 	"log"
 	"net/url"
 
-	http "github.com/bogdanfinn/fhttp"
-	"github.com/bogdanfinn/fhttp/cookiejar"
-	"github.com/bogdanfinn/fhttp/httptest"
+	http "github.com/kernel/fhttp"
+	"github.com/kernel/fhttp/cookiejar"
+	"github.com/kernel/fhttp/httptest"
 )
 
 func Example新建() {

cookiejar/jar.go

@@ -15,7 +15,7 @@ import (
 	"sync"
 	"time"
 
-	http "github.com/bogdanfinn/fhttp"
+	http "github.com/kernel/fhttp"
 )
 
 // PublicSuffixList provides the public suffix of a domain. For example:

cookiejar/jar_test.go

@@ -12,7 +12,7 @@ import (
 	"testing"
 	"time"
 
-	http "github.com/bogdanfinn/fhttp"
+	http "github.com/kernel/fhttp"
 )
 
 // tNow is the synthetic current time used as now during testing.

example_client_test.go

@@ -13,8 +13,8 @@ import (
 
 	tls "github.com/bogdanfinn/utls"
 
-	http "github.com/bogdanfinn/fhttp"
-	"github.com/bogdanfinn/fhttp/http2"
+	http "github.com/kernel/fhttp"
+	"github.com/kernel/fhttp/http2"
 )
 
 // Basic http test with Header Order + enable push

example_filesystem_test.go

@@ -9,7 +9,7 @@ import (
 	"log"
 	"strings"
 
-	http "github.com/bogdanfinn/fhttp"
+	http "github.com/kernel/fhttp"
 )
 
 // containsDotFile reports whether name contains a path element starting with a period.

example_handle_test.go

@@ -9,7 +9,7 @@ import (
 	"log"
 	"sync"
 
-	http "github.com/bogdanfinn/fhttp"
+	http "github.com/kernel/fhttp"
 )
 
 type countHandler struct {

example_test.go

@@ -12,7 +12,7 @@ import (
 	"os"
 	"os/signal"
 
-	http "github.com/bogdanfinn/fhttp"
+	http "github.com/kernel/fhttp"
 )
 
 func ExampleHijacker() {

fcgi/child.go

@@ -17,8 +17,8 @@ import (
 	"sync"
 	"time"
 
-	http "github.com/bogdanfinn/fhttp"
-	"github.com/bogdanfinn/fhttp/cgi"
+	http "github.com/kernel/fhttp"
+	"github.com/kernel/fhttp/cgi"
 )
 
 // request holds the state for an in-progress request. As soon as it's complete,

fcgi/fcgi_test.go

@@ -11,7 +11,7 @@ import (
 	"strings"
 	"testing"
 
-	http "github.com/bogdanfinn/fhttp"
+	http "github.com/kernel/fhttp"
 )
 
 var sizeTests = []struct {

fs_test.go

@@ -27,8 +27,8 @@ import (
 	"testing"
 	"time"
 
-	. "github.com/bogdanfinn/fhttp"
-	"github.com/bogdanfinn/fhttp/httptest"
+	. "github.com/kernel/fhttp"
+	"github.com/kernel/fhttp/httptest"
 )
 
 const (

go.mod

@@ -1,4 +1,4 @@
-module github.com/bogdanfinn/fhttp
+module github.com/kernel/fhttp
 
 go 1.24.1
 

header.go

@@ -12,7 +12,7 @@ import (
 	"sync"
 	"time"
 
-	"github.com/bogdanfinn/fhttp/httptrace"
+	"github.com/kernel/fhttp/httptrace"
 )
 
 // A Header represents the Key-value pairs in an HTTP header.

header_test.go

@@ -11,7 +11,7 @@ import (
 	"testing"
 	"time"
 
-	"github.com/bogdanfinn/fhttp/internal/race"
+	"github.com/kernel/fhttp/internal/race"
 )
 
 var headerWriteTests = []struct {

http.go

@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-//go:generate bundle -o=h2_bundle.go -prefix=http2 -tags=!nethttpomithttp2 github.com/bogdanfinn/fhttp/http2
+//go:generate bundle -o=h2_bundle.go -prefix=http2 -tags=!nethttpomithttp2 github.com/kernel/fhttp/http2
 
 package http
 

http2/client_conn_pool.go

@@ -11,7 +11,7 @@ import (
 
 	tls "github.com/bogdanfinn/utls"
 
-	http "github.com/bogdanfinn/fhttp"
+	http "github.com/kernel/fhttp"
 )
 
 // ClientConnPool manages a pool of HTTP/2 client connections.

http2/fhttp_test.go

@@ -13,13 +13,13 @@ import (
 	"strings"
 	"testing"
 
-	"github.com/bogdanfinn/fhttp/cookiejar"
-	"github.com/bogdanfinn/fhttp/httptest"
+	"github.com/kernel/fhttp/cookiejar"
+	"github.com/kernel/fhttp/httptest"
 	tls "github.com/bogdanfinn/utls"
 	"golang.org/x/net/publicsuffix"
 
-	http "github.com/bogdanfinn/fhttp"
-	"github.com/bogdanfinn/fhttp/http2"
+	http "github.com/kernel/fhttp"
+	"github.com/kernel/fhttp/http2"
 )
 
 // Tests if connection settings are written correctly

http2/flow.go

@@ -50,3 +50,71 @@ func (f *flow) add(n int32) bool {
 	}
 	return false
 }
+
+// inflowMinRefresh is the minimum number of bytes we'll send for a
+// flow control window update.
+const inflowMinRefresh = 4 << 10
+
+// inflow accounts for an inbound flow control window.
+// It tracks both the latest window sent to the peer (used for enforcement)
+// and the accumulated unsent window.
+type inflow struct {
+	avail  int32
+	unsent int32
+}
+
+// init sets the initial window.
+func (f *inflow) init(n int32) {
+	f.avail = n
+}
+
+// add adds n bytes to the window, with a maximum window size of max,
+// indicating that the peer can now send us more data.
+// For example, the user read from a {Request,Response} body and consumed
+// some of the buffered data, so the peer can now send more.
+// It returns the number of bytes to send in a WINDOW_UPDATE frame to the peer.
+// Window updates are accumulated and sent when the unsent capacity
+// is at least inflowMinRefresh or will at least double the peer's available window.
+func (f *inflow) add(n int) (connAdd int32) {
+	if n < 0 {
+		panic("negative update")
+	}
+	unsent := int64(f.unsent) + int64(n)
+	// "A sender MUST NOT allow a flow-control window to exceed 2^31-1 octets."
+	// RFC 7540 Section 6.9.1.
+	const maxWindow = 1<<31 - 1
+	if unsent+int64(f.avail) > maxWindow {
+		panic("flow control update exceeds maximum window size")
+	}
+	f.unsent = int32(unsent)
+	if f.unsent < inflowMinRefresh && f.unsent < f.avail {
+		// If there aren't at least inflowMinRefresh bytes of window to send,
+		// and this update won't at least double the window, buffer the update for later.
+		return 0
+	}
+	f.avail += f.unsent
+	f.unsent = 0
+	return int32(unsent)
+}
+
+// take attempts to take n bytes from the peer's flow control window.
+// It reports whether the window has available capacity.
+func (f *inflow) take(n uint32) bool {
+	if n > uint32(f.avail) {
+		return false
+	}
+	f.avail -= int32(n)
+	return true
+}
+
+// takeInflows attempts to take n bytes from two inflows,
+// typically connection-level and stream-level flows.
+// It reports whether both windows have available capacity.
+func takeInflows(f1, f2 *inflow, n uint32) bool {
+	if n > uint32(f1.avail) || n > uint32(f2.avail) {
+		return false
+	}
+	f1.avail -= int32(n)
+	f2.avail -= int32(n)
+	return true
+}

http2/frame.go

@@ -14,7 +14,7 @@ import (
 	"strings"
 	"sync"
 
-	"github.com/bogdanfinn/fhttp/http2/hpack"
+	"github.com/kernel/fhttp/http2/hpack"
 	"golang.org/x/net/http/httpguts"
 )
 

http2/frame_test.go

@@ -13,7 +13,7 @@ import (
 	"testing"
 	"unsafe"
 
-	"github.com/bogdanfinn/fhttp/http2/hpack"
+	"github.com/kernel/fhttp/http2/hpack"
 )
 
 func testFramer() (*Framer, *bytes.Buffer) {

http2/go111.go

@@ -10,7 +10,7 @@ package http2
 import (
 	"net/textproto"
 
-	"github.com/bogdanfinn/fhttp/httptrace"
+	"github.com/kernel/fhttp/httptrace"
 )
 
 func traceHasWroteHeaderField(trace *httptrace.ClientTrace) bool {

http2/h2c/h2c.go

@@ -22,9 +22,9 @@ import (
 	"os"
 	"strings"
 
-	http "github.com/bogdanfinn/fhttp"
-	"github.com/bogdanfinn/fhttp/http2"
-	"github.com/bogdanfinn/fhttp/http2/hpack"
+	http "github.com/kernel/fhttp"
+	"github.com/kernel/fhttp/http2"
+	"github.com/kernel/fhttp/http2/hpack"
 	"golang.org/x/net/http/httpguts"
 )
 

http2/h2c/h2c_test.go

@@ -11,8 +11,8 @@ import (
 	"log"
 	"testing"
 
-	http "github.com/bogdanfinn/fhttp"
-	"github.com/bogdanfinn/fhttp/http2"
+	http "github.com/kernel/fhttp"
+	"github.com/kernel/fhttp/http2"
 )
 
 func Test设置AckSwallowWriter(t *testing.T) {