internal/strs: unify string manipulation functionality
Create a new internal/strs package that unifies common functionality:
* Since protobuf itself pseudo-specifies at least 4 different camel-case
and snake-case conversion functions, we define all variants in one place.
* We move the internal/filedesc.nameBuilder function to this package.
We simplify its implementation to not depend on a strings.Builder fork
under the hood since the semantics we desire is simpler than what
strings.Builder provides.
* We use strs.Builder in reflect/protodesc in its construction of all
the full names. This is perfect use case of strs.Builder since all
full names within a file descriptor share the same lifetime.
* Add an UnsafeString and UnsafeBytes cast function that will be useful
in the near future for optimizing encoding/prototext and encoding/protojson.
Change-Id: I2cf07cbaf6f72e5f9fd6ae3d37b0d46f6af2ad59
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/185198
Reviewed-by: Damien Neil <dneil@google.com>
diff --git a/internal/filedesc/desc_init.go b/internal/filedesc/desc_init.go
index a51a7ec..0bd7d38 100644
--- a/internal/filedesc/desc_init.go
+++ b/internal/filedesc/desc_init.go
@@ -5,8 +5,11 @@
package filedesc
import (
+ "sync"
+
"google.golang.org/protobuf/internal/encoding/wire"
"google.golang.org/protobuf/internal/fieldnum"
+ "google.golang.org/protobuf/internal/strs"
pref "google.golang.org/protobuf/reflect/protoreflect"
)
@@ -89,8 +92,8 @@
}
func (fd *File) unmarshalSeed(b []byte) {
- nb := getNameBuilder()
- defer putNameBuilder(nb)
+ sb := getBuilder()
+ defer putBuilder(sb)
var prevField pref.FieldNumber
var numEnums, numMessages, numExtensions, numServices int
@@ -114,9 +117,9 @@
panic("invalid syntax")
}
case fieldnum.FileDescriptorProto_Name:
- fd.L1.Path = nb.MakeString(v)
+ fd.L1.Path = sb.MakeString(v)
case fieldnum.FileDescriptorProto_Package:
- fd.L1.Package = pref.FullName(nb.MakeString(v))
+ fd.L1.Package = pref.FullName(sb.MakeString(v))
case fieldnum.FileDescriptorProto_EnumType:
if prevField != fieldnum.FileDescriptorProto_EnumType {
if numEnums > 0 {
@@ -183,7 +186,7 @@
for i := range fd.L1.Enums.List {
_, n := wire.ConsumeVarint(b)
v, m := wire.ConsumeBytes(b[n:])
- fd.L1.Enums.List[i].unmarshalSeed(v, nb, fd, fd, i)
+ fd.L1.Enums.List[i].unmarshalSeed(v, sb, fd, fd, i)
b = b[n+m:]
}
}
@@ -192,7 +195,7 @@
for i := range fd.L1.Messages.List {
_, n := wire.ConsumeVarint(b)
v, m := wire.ConsumeBytes(b[n:])
- fd.L1.Messages.List[i].unmarshalSeed(v, nb, fd, fd, i)
+ fd.L1.Messages.List[i].unmarshalSeed(v, sb, fd, fd, i)
b = b[n+m:]
}
}
@@ -201,7 +204,7 @@
for i := range fd.L1.Extensions.List {
_, n := wire.ConsumeVarint(b)
v, m := wire.ConsumeBytes(b[n:])
- fd.L1.Extensions.List[i].unmarshalSeed(v, nb, fd, fd, i)
+ fd.L1.Extensions.List[i].unmarshalSeed(v, sb, fd, fd, i)
b = b[n+m:]
}
}
@@ -210,13 +213,13 @@
for i := range fd.L1.Services.List {
_, n := wire.ConsumeVarint(b)
v, m := wire.ConsumeBytes(b[n:])
- fd.L1.Services.List[i].unmarshalSeed(v, nb, fd, fd, i)
+ fd.L1.Services.List[i].unmarshalSeed(v, sb, fd, fd, i)
b = b[n+m:]
}
}
}
-func (ed *Enum) unmarshalSeed(b []byte, nb *nameBuilder, pf *File, pd pref.Descriptor, i int) {
+func (ed *Enum) unmarshalSeed(b []byte, sb *strs.Builder, pf *File, pd pref.Descriptor, i int) {
ed.L0.ParentFile = pf
ed.L0.Parent = pd
ed.L0.Index = i
@@ -231,7 +234,7 @@
b = b[m:]
switch num {
case fieldnum.EnumDescriptorProto_Name:
- ed.L0.FullName = nb.AppendFullName(pd.FullName(), v)
+ ed.L0.FullName = appendFullName(sb, pd.FullName(), v)
case fieldnum.EnumDescriptorProto_Value:
numValues++
}
@@ -258,7 +261,7 @@
b = b[m:]
switch num {
case fieldnum.EnumDescriptorProto_Value:
- ed.L2.Values.List[i].unmarshalFull(v, nb, pf, ed, i)
+ ed.L2.Values.List[i].unmarshalFull(v, sb, pf, ed, i)
i++
}
default:
@@ -268,7 +271,7 @@
}
}
-func (md *Message) unmarshalSeed(b []byte, nb *nameBuilder, pf *File, pd pref.Descriptor, i int) {
+func (md *Message) unmarshalSeed(b []byte, sb *strs.Builder, pf *File, pd pref.Descriptor, i int) {
md.L0.ParentFile = pf
md.L0.Parent = pd
md.L0.Index = i
@@ -286,7 +289,7 @@
b = b[m:]
switch num {
case fieldnum.DescriptorProto_Name:
- md.L0.FullName = nb.AppendFullName(pd.FullName(), v)
+ md.L0.FullName = appendFullName(sb, pd.FullName(), v)
case fieldnum.DescriptorProto_EnumType:
if prevField != fieldnum.DescriptorProto_EnumType {
if numEnums > 0 {
@@ -337,7 +340,7 @@
for i := range md.L1.Enums.List {
_, n := wire.ConsumeVarint(b)
v, m := wire.ConsumeBytes(b[n:])
- md.L1.Enums.List[i].unmarshalSeed(v, nb, pf, md, i)
+ md.L1.Enums.List[i].unmarshalSeed(v, sb, pf, md, i)
b = b[n+m:]
}
}
@@ -346,7 +349,7 @@
for i := range md.L1.Messages.List {
_, n := wire.ConsumeVarint(b)
v, m := wire.ConsumeBytes(b[n:])
- md.L1.Messages.List[i].unmarshalSeed(v, nb, pf, md, i)
+ md.L1.Messages.List[i].unmarshalSeed(v, sb, pf, md, i)
b = b[n+m:]
}
}
@@ -355,13 +358,13 @@
for i := range md.L1.Extensions.List {
_, n := wire.ConsumeVarint(b)
v, m := wire.ConsumeBytes(b[n:])
- md.L1.Extensions.List[i].unmarshalSeed(v, nb, pf, md, i)
+ md.L1.Extensions.List[i].unmarshalSeed(v, sb, pf, md, i)
b = b[n+m:]
}
}
}
-func (xd *Extension) unmarshalSeed(b []byte, nb *nameBuilder, pf *File, pd pref.Descriptor, i int) {
+func (xd *Extension) unmarshalSeed(b []byte, sb *strs.Builder, pf *File, pd pref.Descriptor, i int) {
xd.L0.ParentFile = pf
xd.L0.Parent = pd
xd.L0.Index = i
@@ -384,9 +387,9 @@
b = b[m:]
switch num {
case fieldnum.FieldDescriptorProto_Name:
- xd.L0.FullName = nb.AppendFullName(pd.FullName(), v)
+ xd.L0.FullName = appendFullName(sb, pd.FullName(), v)
case fieldnum.FieldDescriptorProto_Extendee:
- xd.L1.Extendee = PlaceholderMessage(nb.MakeFullName(v))
+ xd.L1.Extendee = PlaceholderMessage(makeFullName(sb, v))
}
default:
m := wire.ConsumeFieldValue(num, typ, b)
@@ -395,7 +398,7 @@
}
}
-func (sd *Service) unmarshalSeed(b []byte, nb *nameBuilder, pf *File, pd pref.Descriptor, i int) {
+func (sd *Service) unmarshalSeed(b []byte, sb *strs.Builder, pf *File, pd pref.Descriptor, i int) {
sd.L0.ParentFile = pf
sd.L0.Parent = pd
sd.L0.Index = i
@@ -409,7 +412,7 @@
b = b[m:]
switch num {
case fieldnum.ServiceDescriptorProto_Name:
- sd.L0.FullName = nb.AppendFullName(pd.FullName(), v)
+ sd.L0.FullName = appendFullName(sb, pd.FullName(), v)
}
default:
m := wire.ConsumeFieldValue(num, typ, b)
@@ -417,3 +420,27 @@
}
}
}
+
+var nameBuilderPool = sync.Pool{
+ New: func() interface{} { return new(strs.Builder) },
+}
+
+func getBuilder() *strs.Builder {
+ return nameBuilderPool.Get().(*strs.Builder)
+}
+func putBuilder(b *strs.Builder) {
+ nameBuilderPool.Put(b)
+}
+
+// makeFullName converts b to a protoreflect.FullName,
+// where b must start with a leading dot.
+func makeFullName(sb *strs.Builder, b []byte) pref.FullName {
+ if len(b) == 0 || b[0] != '.' {
+ panic("name reference must be fully qualified")
+ }
+ return pref.FullName(sb.MakeString(b[1:]))
+}
+
+func appendFullName(sb *strs.Builder, prefix pref.FullName, suffix []byte) pref.FullName {
+ return sb.AppendFullName(prefix, pref.Name(strs.UnsafeString(suffix)))
+}