var hf HeaderField
wantStr := d.emitEnabled || it.indexed()
+ var undecodedName undecodedString
if nameIdx > 0 {
ihf, ok := d.at(nameIdx)
if !ok {
}
hf.Name = ihf.Name
} else {
- hf.Name, buf, err = d.readString(buf, wantStr)
+ undecodedName, buf, err = d.readString(buf)
if err != nil {
return err
}
}
- hf.Value, buf, err = d.readString(buf, wantStr)
+ undecodedValue, buf, err := d.readString(buf)
if err != nil {
return err
}
+ if wantStr {
+ if nameIdx <= 0 {
+ hf.Name, err = d.decodeString(undecodedName)
+ if err != nil {
+ return err
+ }
+ }
+ hf.Value, err = d.decodeString(undecodedValue)
+ if err != nil {
+ return err
+ }
+ }
d.buf = buf
if it.indexed() {
d.dynTab.add(hf)
return 0, origP, errNeedMore
}
-// readString decodes an hpack string from p.
+// readString reads an hpack string from p.
//
-// wantStr is whether s will be used. If false, decompression and
-// []byte->string garbage are skipped if s will be ignored
-// anyway. This does mean that huffman decoding errors for non-indexed
-// strings past the MAX_HEADER_LIST_SIZE are ignored, but the server
-// is returning an error anyway, and because they're not indexed, the error
-// won't affect the decoding state.
-func (d *Decoder) readString(p []byte, wantStr bool) (s string, remain []byte, err error) {
+// It returns a reference to the encoded string data to permit deferring decode costs
+// until after the caller verifies all data is present.
+func (d *Decoder) readString(p []byte) (u undecodedString, remain []byte, err error) {
if len(p) == 0 {
- return "", p, errNeedMore
+ return u, p, errNeedMore
}
isHuff := p[0]&128 != 0
strLen, p, err := readVarInt(7, p)
if err != nil {
- return "", p, err
+ return u, p, err
}
if d.maxStrLen != 0 && strLen > uint64(d.maxStrLen) {
- return "", nil, ErrStringLength
+ // Returning an error here means Huffman decoding errors
+ // for non-indexed strings past the maximum string length
+ // are ignored, but the server is returning an error anyway
+ // and because the string is not indexed the error will not
+ // affect the decoding state.
+ return u, nil, ErrStringLength
}
if uint64(len(p)) < strLen {
- return "", p, errNeedMore
- }
- if !isHuff {
- if wantStr {
- s = string(p[:strLen])
- }
- return s, p[strLen:], nil
+ return u, p, errNeedMore
}
+ u.isHuff = isHuff
+ u.b = p[:strLen]
+ return u, p[strLen:], nil
+}
- if wantStr {
- buf := bufPool.Get().(*bytes.Buffer)
- buf.Reset() // don't trust others
- defer bufPool.Put(buf)
- if err := huffmanDecode(buf, d.maxStrLen, p[:strLen]); err != nil {
- buf.Reset()
- return "", nil, err
- }
+type undecodedString struct {
+ isHuff bool
+ b []byte
+}
+
+func (d *Decoder) decodeString(u undecodedString) (string, error) {
+ if !u.isHuff {
+ return string(u.b), nil
+ }
+ buf := bufPool.Get().(*bytes.Buffer)
+ buf.Reset() // don't trust others
+ var s string
+ err := huffmanDecode(buf, d.maxStrLen, u.b)
+ if err == nil {
s = buf.String()
- buf.Reset() // be nice to GC
}
- return s, p[strLen:], nil
+ buf.Reset() // be nice to GC
+ bufPool.Put(buf)
+ return s, err
}