Make Fuzz tests deterministic

From the Go docs:
- Fuzz targets should be fast and deterministic so the fuzzing engine can work efficiently, and new failures and code coverage can be easily reproduced.
- Since the fuzz target is invoked in parallel across multiple workers and in nondeterministic order, the state of a fuzz target should not persist past the end of each call, and the behavior of a fuzz target should not depend on global state.

fuzz_test.go

@@ -7,17 +7,13 @@ import (
 )
 
 func FuzzCookieParse(f *testing.F) {
-	inputs := []string{
-		`xxx=yyy`,
-		`xxx=yyy; expires=Tue, 10 Nov 2009 23:00:00 GMT; domain=foobar.com; path=/a/b`,
-		" \n\t\"",
-	}
-	for _, input := range inputs {
-		f.Add([]byte(input))
-	}
-	c := AcquireCookie()
-	defer ReleaseCookie(c)
+	f.Add([]byte(`xxx=yyy`))
+	f.Add([]byte(`xxx=yyy; expires=Tue, 10 Nov 2009 23:00:00 GMT; domain=foobar.com; path=/a/b`))
+	f.Add([]byte(" \n\t\""))
+
 	f.Fuzz(func(t *testing.T, cookie []byte) {
+		var c Cookie
+
 		_ = c.ParseBytes(cookie)
 
 		w := bytes.Buffer{}
@@ -28,15 +24,11 @@ func FuzzCookieParse(f *testing.F) {
 }
 
 func FuzzVisitHeaderParams(f *testing.F) {
-	inputs := []string{
-		`application/json; v=1; foo=bar; q=0.938; param=param; param="big fox"; q=0.43`,
-		`*/*`,
-		`\\`,
-		`text/plain; foo="\\\"\'\\''\'"`,
-	}
-	for _, input := range inputs {
-		f.Add([]byte(input))
-	}
+	f.Add([]byte(`application/json; v=1; foo=bar; q=0.938; param=param; param="big fox"; q=0.43`))
+	f.Add([]byte(`*/*`))
+	f.Add([]byte(`\\`))
+	f.Add([]byte(`text/plain; foo="\\\"\'\\''\'"`))
+
 	f.Fuzz(func(t *testing.T, header []byte) {
 		VisitHeaderParams(header, func(key, value []byte) bool {
 			if len(key) == 0 {
@@ -48,49 +40,46 @@ func FuzzVisitHeaderParams(f *testing.F) {
 }
 
 func FuzzResponseReadLimitBody(f *testing.F) {
-	res := AcquireResponse()
-	defer ReleaseResponse(res)
-
-	f.Add([]byte("HTTP/1.1 200 OK\r\nContent-Type: aa\r\nContent-Length: 10\r\n\r\n9876543210"), 1024*1024)
+	f.Add([]byte("HTTP/1.1 200 OK\r\nContent-Type: aa\r\nContent-Length: 10\r\n\r\n9876543210"), 1024)
 
 	f.Fuzz(func(t *testing.T, body []byte, max int) {
-		if max > 10*1024*1024 { // Skip limits higher than 10MB.
+		if max > 1024*1024 { // Skip limits higher than 1MB.
 			return
 		}
 
+		var res Response
+
 		_ = res.ReadLimitBody(bufio.NewReader(bytes.NewReader(body)), max)
 		w := bytes.Buffer{}
 		_, _ = res.WriteTo(&w)
 	})
 }
 
 func FuzzRequestReadLimitBody(f *testing.F) {
-	req := AcquireRequest()
-	defer ReleaseRequest(req)
-
-	f.Add([]byte("POST /a HTTP/1.1\r\nHost: a.com\r\nTransfer-Encoding: chunked\r\nContent-Type: aa\r\n\r\n6\r\nfoobar\r\n3\r\nbaz\r\n0\r\nfoobar\r\n\r\n"), 1024*1024)
+	f.Add([]byte("POST /a HTTP/1.1\r\nHost: a.com\r\nTransfer-Encoding: chunked\r\nContent-Type: aa\r\n\r\n6\r\nfoobar\r\n3\r\nbaz\r\n0\r\nfoobar\r\n\r\n"), 1024)
 
 	f.Fuzz(func(t *testing.T, body []byte, max int) {
-		if max > 10*1024*1024 { // Skip limits higher than 10MB.
+		if max > 1024*1024 { // Skip limits higher than 1MB.
 			return
 		}
 
+		var req Request
+
 		_ = req.ReadLimitBody(bufio.NewReader(bytes.NewReader(body)), max)
 		w := bytes.Buffer{}
 		_, _ = req.WriteTo(&w)
 	})
 }
 
 func FuzzURIUpdateBytes(f *testing.F) {
-	u := AcquireURI()
-	defer ReleaseURI(u)
-
 	f.Add([]byte(`http://foobar.com/aaa/bb?cc`))
 	f.Add([]byte(`//foobar.com/aaa/bb?cc`))
 	f.Add([]byte(`/aaa/bb?cc`))
 	f.Add([]byte(`xx?yy=abc`))
 
 	f.Fuzz(func(t *testing.T, uri []byte) {
+		var u URI
+
 		u.UpdateBytes(uri)
 
 		w := bytes.Buffer{}