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-rw-r--r--pkg/abi/linux/BUILD1
-rw-r--r--pkg/abi/linux/netfilter.go73
-rw-r--r--pkg/abi/linux/netfilter_ipv6.go67
-rw-r--r--tools/go_marshal/README.md12
-rw-r--r--tools/go_marshal/gomarshal/generator.go31
-rw-r--r--tools/go_marshal/gomarshal/generator_interfaces_struct.go339
-rw-r--r--tools/go_marshal/gomarshal/generator_tests.go12
-rw-r--r--tools/go_marshal/test/BUILD6
-rw-r--r--tools/go_marshal/test/marshal_test.go19
-rw-r--r--tools/go_marshal/test/test.go35
10 files changed, 293 insertions, 302 deletions
diff --git a/pkg/abi/linux/BUILD b/pkg/abi/linux/BUILD
index 8fa61d6f7..ecaeb11ac 100644
--- a/pkg/abi/linux/BUILD
+++ b/pkg/abi/linux/BUILD
@@ -80,7 +80,6 @@ go_library(
"//pkg/bits",
"//pkg/marshal",
"//pkg/marshal/primitive",
- "//pkg/usermem",
],
)
diff --git a/pkg/abi/linux/netfilter.go b/pkg/abi/linux/netfilter.go
index b521144d9..378f1baf3 100644
--- a/pkg/abi/linux/netfilter.go
+++ b/pkg/abi/linux/netfilter.go
@@ -15,11 +15,8 @@
package linux
import (
- "io"
-
"gvisor.dev/gvisor/pkg/marshal"
"gvisor.dev/gvisor/pkg/marshal/primitive"
- "gvisor.dev/gvisor/pkg/usermem"
)
// This file contains structures required to support netfilter, specifically
@@ -129,8 +126,8 @@ type IPTEntry struct {
const SizeOfIPTEntry = 112
// KernelIPTEntry is identical to IPTEntry, but includes the Elems field.
-// KernelIPTEntry itself is not Marshallable but it implements some methods of
-// marshal.Marshallable that help in other implementations of Marshallable.
+//
+// +marshal dynamic
type KernelIPTEntry struct {
Entry IPTEntry
@@ -158,6 +155,8 @@ func (ke *KernelIPTEntry) UnmarshalBytes(src []byte) {
ke.Elems.UnmarshalBytes(src[ke.Entry.SizeBytes():])
}
+var _ marshal.Marshallable = (*KernelIPTEntry)(nil)
+
// IPTIP contains information for matching a packet's IP header.
// It corresponds to struct ipt_ip in
// include/uapi/linux/netfilter_ipv4/ip_tables.h.
@@ -411,8 +410,9 @@ type IPTGetEntries struct {
const SizeOfIPTGetEntries = 40
// KernelIPTGetEntries is identical to IPTGetEntries, but includes the
-// Entrytable field. This has been manually made marshal.Marshallable since it
-// is dynamically sized.
+// Entrytable field.
+//
+// +marshal dynamic
type KernelIPTGetEntries struct {
IPTGetEntries
Entrytable []KernelIPTEntry
@@ -447,65 +447,6 @@ func (ke *KernelIPTGetEntries) UnmarshalBytes(src []byte) {
}
}
-// Packed implements marshal.Marshallable.Packed.
-func (ke *KernelIPTGetEntries) Packed() bool {
- // KernelIPTGetEntries isn't packed because the ke.Entrytable contains an
- // indirection to the actual data we want to marshal (the slice data
- // pointer), and the memory for KernelIPTGetEntries contains the slice
- // header which we don't want to marshal.
- return false
-}
-
-// MarshalUnsafe implements marshal.Marshallable.MarshalUnsafe.
-func (ke *KernelIPTGetEntries) MarshalUnsafe(dst []byte) {
- // Fall back to safe Marshal because the type in not packed.
- ke.MarshalBytes(dst)
-}
-
-// UnmarshalUnsafe implements marshal.Marshallable.UnmarshalUnsafe.
-func (ke *KernelIPTGetEntries) UnmarshalUnsafe(src []byte) {
- // Fall back to safe Unmarshal because the type in not packed.
- ke.UnmarshalBytes(src)
-}
-
-// CopyIn implements marshal.Marshallable.CopyIn.
-func (ke *KernelIPTGetEntries) CopyIn(cc marshal.CopyContext, addr usermem.Addr) (int, error) {
- buf := cc.CopyScratchBuffer(ke.SizeBytes()) // escapes: okay.
- length, err := cc.CopyInBytes(addr, buf) // escapes: okay.
- // Unmarshal unconditionally. If we had a short copy-in, this results in a
- // partially unmarshalled struct.
- ke.UnmarshalBytes(buf) // escapes: fallback.
- return length, err
-}
-
-// CopyOut implements marshal.Marshallable.CopyOut.
-func (ke *KernelIPTGetEntries) CopyOut(cc marshal.CopyContext, addr usermem.Addr) (int, error) {
- // Type KernelIPTGetEntries doesn't have a packed layout in memory, fall
- // back to MarshalBytes.
- return cc.CopyOutBytes(addr, ke.marshalAll(cc))
-}
-
-// CopyOutN implements marshal.Marshallable.CopyOutN.
-func (ke *KernelIPTGetEntries) CopyOutN(cc marshal.CopyContext, addr usermem.Addr, limit int) (int, error) {
- // Type KernelIPTGetEntries doesn't have a packed layout in memory, fall
- // back to MarshalBytes.
- return cc.CopyOutBytes(addr, ke.marshalAll(cc)[:limit])
-}
-
-func (ke *KernelIPTGetEntries) marshalAll(cc marshal.CopyContext) []byte {
- buf := cc.CopyScratchBuffer(ke.SizeBytes())
- ke.MarshalBytes(buf)
- return buf
-}
-
-// WriteTo implements io.WriterTo.WriteTo.
-func (ke *KernelIPTGetEntries) WriteTo(w io.Writer) (int64, error) {
- buf := make([]byte, ke.SizeBytes())
- ke.MarshalBytes(buf)
- length, err := w.Write(buf)
- return int64(length), err
-}
-
var _ marshal.Marshallable = (*KernelIPTGetEntries)(nil)
// IPTReplace is the argument for the IPT_SO_SET_REPLACE sockopt. It
diff --git a/pkg/abi/linux/netfilter_ipv6.go b/pkg/abi/linux/netfilter_ipv6.go
index bcb57642e..b953e62dc 100644
--- a/pkg/abi/linux/netfilter_ipv6.go
+++ b/pkg/abi/linux/netfilter_ipv6.go
@@ -15,11 +15,8 @@
package linux
import (
- "io"
-
"gvisor.dev/gvisor/pkg/marshal"
"gvisor.dev/gvisor/pkg/marshal/primitive"
- "gvisor.dev/gvisor/pkg/usermem"
)
// This file contains structures required to support IPv6 netfilter and
@@ -70,8 +67,9 @@ type IP6TReplace struct {
const SizeOfIP6TReplace = 96
// KernelIP6TGetEntries is identical to IP6TGetEntries, but includes the
-// Entrytable field. This has been manually made marshal.Marshallable since it
-// is dynamically sized.
+// Entrytable field.
+//
+// +marshal dynamic
type KernelIP6TGetEntries struct {
IPTGetEntries
Entrytable []KernelIP6TEntry
@@ -106,65 +104,6 @@ func (ke *KernelIP6TGetEntries) UnmarshalBytes(src []byte) {
}
}
-// Packed implements marshal.Marshallable.Packed.
-func (ke *KernelIP6TGetEntries) Packed() bool {
- // KernelIP6TGetEntries isn't packed because the ke.Entrytable contains
- // an indirection to the actual data we want to marshal (the slice data
- // pointer), and the memory for KernelIP6TGetEntries contains the slice
- // header which we don't want to marshal.
- return false
-}
-
-// MarshalUnsafe implements marshal.Marshallable.MarshalUnsafe.
-func (ke *KernelIP6TGetEntries) MarshalUnsafe(dst []byte) {
- // Fall back to safe Marshal because the type in not packed.
- ke.MarshalBytes(dst)
-}
-
-// UnmarshalUnsafe implements marshal.Marshallable.UnmarshalUnsafe.
-func (ke *KernelIP6TGetEntries) UnmarshalUnsafe(src []byte) {
- // Fall back to safe Unmarshal because the type in not packed.
- ke.UnmarshalBytes(src)
-}
-
-// CopyIn implements marshal.Marshallable.CopyIn.
-func (ke *KernelIP6TGetEntries) CopyIn(cc marshal.CopyContext, addr usermem.Addr) (int, error) {
- buf := cc.CopyScratchBuffer(ke.SizeBytes()) // escapes: okay.
- length, err := cc.CopyInBytes(addr, buf) // escapes: okay.
- // Unmarshal unconditionally. If we had a short copy-in, this results
- // in a partially unmarshalled struct.
- ke.UnmarshalBytes(buf) // escapes: fallback.
- return length, err
-}
-
-// CopyOut implements marshal.Marshallable.CopyOut.
-func (ke *KernelIP6TGetEntries) CopyOut(cc marshal.CopyContext, addr usermem.Addr) (int, error) {
- // Type KernelIP6TGetEntries doesn't have a packed layout in memory,
- // fall back to MarshalBytes.
- return cc.CopyOutBytes(addr, ke.marshalAll(cc))
-}
-
-// CopyOutN implements marshal.Marshallable.CopyOutN.
-func (ke *KernelIP6TGetEntries) CopyOutN(cc marshal.CopyContext, addr usermem.Addr, limit int) (int, error) {
- // Type KernelIP6TGetEntries doesn't have a packed layout in memory, fall
- // back to MarshalBytes.
- return cc.CopyOutBytes(addr, ke.marshalAll(cc)[:limit])
-}
-
-func (ke *KernelIP6TGetEntries) marshalAll(cc marshal.CopyContext) []byte {
- buf := cc.CopyScratchBuffer(ke.SizeBytes())
- ke.MarshalBytes(buf)
- return buf
-}
-
-// WriteTo implements io.WriterTo.WriteTo.
-func (ke *KernelIP6TGetEntries) WriteTo(w io.Writer) (int64, error) {
- buf := make([]byte, ke.SizeBytes())
- ke.MarshalBytes(buf)
- length, err := w.Write(buf)
- return int64(length), err
-}
-
var _ marshal.Marshallable = (*KernelIP6TGetEntries)(nil)
// IP6TEntry is an iptables rule. It corresponds to struct ip6t_entry in
diff --git a/tools/go_marshal/README.md b/tools/go_marshal/README.md
index d8045c295..eddba0c21 100644
--- a/tools/go_marshal/README.md
+++ b/tools/go_marshal/README.md
@@ -98,6 +98,18 @@ for embedded structs that are not aligned.
Because of this, it's generally best to avoid using `marshal:"unaligned"` and
insert explicit padding fields instead.
+## Working with dynamically sized structs
+
+While `go_marshal` seamlessly supports statically sized structs (which most ABI
+structs are), it can also used for other uses cases where marshalling is
+required. There is some provision to partially support dynamically sized structs
+that may not be ABI structs. A user can define a dynamic struct and define
+`SizeBytes()`, `MarshalBytes(dst)` and `UnmarshalBytes(src)` for it. Then user
+can then add a comment above the struct like `// +marshal dynamic` while will
+make `go_marshal` autogenerate the remaining methods required to complete the
+`Marshallable` interface. This feature is currently only available for structs
+and can not be used alongside the Slice API.
+
## Modifying the `go_marshal` Tool
The following are some guidelines for modifying the `go_marshal` tool:
diff --git a/tools/go_marshal/gomarshal/generator.go b/tools/go_marshal/gomarshal/generator.go
index fa642c88a..abd6f69ea 100644
--- a/tools/go_marshal/gomarshal/generator.go
+++ b/tools/go_marshal/gomarshal/generator.go
@@ -211,9 +211,10 @@ type sliceAPI struct {
// marshallableType carries information about a type marked with the '+marshal'
// directive.
type marshallableType struct {
- spec *ast.TypeSpec
- slice *sliceAPI
- recv string
+ spec *ast.TypeSpec
+ slice *sliceAPI
+ recv string
+ dynamic bool
}
func newMarshallableType(fset *token.FileSet, tagLine *ast.Comment, spec *ast.TypeSpec) *marshallableType {
@@ -248,6 +249,9 @@ func newMarshallableType(fset *token.FileSet, tagLine *ast.Comment, spec *ast.Ty
}
continue
+ } else if tag == "dynamic" {
+ mt.dynamic = true
+ continue
}
unhandledTags = append(unhandledTags, tag)
@@ -379,23 +383,38 @@ func (g *Generator) generateOne(t *marshallableType, fset *token.FileSet) *inter
i := newInterfaceGenerator(t.spec, t.recv, fset)
switch ty := t.spec.Type.(type) {
case *ast.StructType:
+ if t.dynamic {
+ // Don't validate because this type is dynamically sized and probably
+ // contains some funky slices which the validation does not allow.
+ i.emitMarshallableForStruct(ty, t.dynamic)
+ if t.slice != nil {
+ abortAt(fset.Position(t.slice.comment.Slash), "Slice API is not supported for dynamic types because it assumes that each slice element is statically sized.")
+ }
+ break
+ }
i.validateStruct(t.spec, ty)
- i.emitMarshallableForStruct(ty)
+ i.emitMarshallableForStruct(ty, t.dynamic)
if t.slice != nil {
i.emitMarshallableSliceForStruct(ty, t.slice)
}
case *ast.Ident:
i.validatePrimitiveNewtype(ty)
+ if t.dynamic {
+ abortAt(fset.Position(t.slice.comment.Slash), "Primitive type marked as '+marshal dynamic', but primitive types can not be dynamic.")
+ }
i.emitMarshallableForPrimitiveNewtype(ty)
if t.slice != nil {
i.emitMarshallableSliceForPrimitiveNewtype(ty, t.slice)
}
case *ast.ArrayType:
i.validateArrayNewtype(t.spec.Name, ty)
+ if t.dynamic {
+ abortAt(fset.Position(t.slice.comment.Slash), "Marking array types as `dynamic` is currently not supported.")
+ }
// After validate, we can safely call arrayLen.
i.emitMarshallableForArrayNewtype(t.spec.Name, ty, ty.Elt.(*ast.Ident))
if t.slice != nil {
- abortAt(fset.Position(t.slice.comment.Slash), fmt.Sprintf("Array type marked as '+marshal slice:...', but this is not supported. Perhaps fold one of the dimensions?"))
+ abortAt(fset.Position(t.slice.comment.Slash), "Array type marked as '+marshal slice:...', but this is not supported. Perhaps fold one of the dimensions?")
}
default:
// This should've been filtered out by collectMarshallabeTypes.
@@ -408,7 +427,7 @@ func (g *Generator) generateOne(t *marshallableType, fset *token.FileSet) *inter
// implementations type t.
func (g *Generator) generateOneTestSuite(t *marshallableType) *testGenerator {
i := newTestGenerator(t.spec, t.recv)
- i.emitTests(t.slice)
+ i.emitTests(t.slice, t.dynamic)
return i
}
diff --git a/tools/go_marshal/gomarshal/generator_interfaces_struct.go b/tools/go_marshal/gomarshal/generator_interfaces_struct.go
index 5f6306b8f..f98e41ed7 100644
--- a/tools/go_marshal/gomarshal/generator_interfaces_struct.go
+++ b/tools/go_marshal/gomarshal/generator_interfaces_struct.go
@@ -69,7 +69,11 @@ func (g *interfaceGenerator) validateStruct(ts *ast.TypeSpec, st *ast.StructType
})
}
-func (g *interfaceGenerator) isStructPacked(st *ast.StructType) bool {
+func (g *interfaceGenerator) isStructPacked(st *ast.StructType, isDynamic bool) bool {
+ if isDynamic {
+ // Dynamic types are not packed because a slice header might be present.
+ return false
+ }
packed := true
forEachStructField(st, func(f *ast.Field) {
if f.Tag != nil {
@@ -85,165 +89,17 @@ func (g *interfaceGenerator) isStructPacked(st *ast.StructType) bool {
return packed
}
-func (g *interfaceGenerator) emitMarshallableForStruct(st *ast.StructType) {
- thisPacked := g.isStructPacked(st)
-
- g.emit("// SizeBytes implements marshal.Marshallable.SizeBytes.\n")
- g.emit("func (%s *%s) SizeBytes() int {\n", g.r, g.typeName())
- g.inIndent(func() {
- primitiveSize := 0
- var dynamicSizeTerms []string
-
- forEachStructField(st, fieldDispatcher{
- primitive: func(_, t *ast.Ident) {
- if size, dynamic := g.scalarSize(t); !dynamic {
- primitiveSize += size
- } else {
- g.recordUsedMarshallable(t.Name)
- dynamicSizeTerms = append(dynamicSizeTerms, fmt.Sprintf("(*%s)(nil).SizeBytes()", t.Name))
- }
- },
- selector: func(_, tX, tSel *ast.Ident) {
- tName := fmt.Sprintf("%s.%s", tX.Name, tSel.Name)
- g.recordUsedImport(tX.Name)
- g.recordUsedMarshallable(tName)
- dynamicSizeTerms = append(dynamicSizeTerms, fmt.Sprintf("(*%s)(nil).SizeBytes()", tName))
- },
- array: func(_ *ast.Ident, a *ast.ArrayType, t *ast.Ident) {
- lenExpr := g.arrayLenExpr(a)
- if size, dynamic := g.scalarSize(t); !dynamic {
- dynamicSizeTerms = append(dynamicSizeTerms, fmt.Sprintf("%d*%s", size, lenExpr))
- } else {
- g.recordUsedMarshallable(t.Name)
- dynamicSizeTerms = append(dynamicSizeTerms, fmt.Sprintf("(*%s)(nil).SizeBytes()*%s", t.Name, lenExpr))
- }
- },
- }.dispatch)
- g.emit("return %d", primitiveSize)
- if len(dynamicSizeTerms) > 0 {
- g.incIndent()
- }
- {
- for _, d := range dynamicSizeTerms {
- g.emitNoIndent(" +\n")
- g.emit(d)
- }
- }
- if len(dynamicSizeTerms) > 0 {
- g.decIndent()
- }
- })
- g.emit("\n}\n\n")
+func (g *interfaceGenerator) emitMarshallableForStruct(st *ast.StructType, isDynamic bool) {
+ thisPacked := g.isStructPacked(st, isDynamic)
- g.emit("// MarshalBytes implements marshal.Marshallable.MarshalBytes.\n")
- g.emit("func (%s *%s) MarshalBytes(dst []byte) {\n", g.r, g.typeName())
- g.inIndent(func() {
- forEachStructField(st, fieldDispatcher{
- primitive: func(n, t *ast.Ident) {
- if n.Name == "_" {
- g.emit("// Padding: dst[:sizeof(%s)] ~= %s(0)\n", t.Name, t.Name)
- if len, dynamic := g.scalarSize(t); !dynamic {
- g.shift("dst", len)
- } else {
- // We can't use shiftDynamic here because we don't have
- // an instance of the dynamic type we can reference here
- // (since the version in this struct is anonymous). Use
- // a typed nil pointer to call SizeBytes() instead.
- g.emit("dst = dst[(*%s)(nil).SizeBytes():]\n", t.Name)
- }
- return
- }
- g.marshalScalar(g.fieldAccessor(n), t.Name, "dst")
- },
- selector: func(n, tX, tSel *ast.Ident) {
- if n.Name == "_" {
- g.emit("// Padding: dst[:sizeof(%s)] ~= %s(0)\n", tX.Name, tSel.Name)
- g.emit("dst = dst[(*%s.%s)(nil).SizeBytes():]\n", tX.Name, tSel.Name)
- return
- }
- g.marshalScalar(g.fieldAccessor(n), fmt.Sprintf("%s.%s", tX.Name, tSel.Name), "dst")
- },
- array: func(n *ast.Ident, a *ast.ArrayType, t *ast.Ident) {
- lenExpr := g.arrayLenExpr(a)
- if n.Name == "_" {
- g.emit("// Padding: dst[:sizeof(%s)*%s] ~= [%s]%s{0}\n", t.Name, lenExpr, lenExpr, t.Name)
- if size, dynamic := g.scalarSize(t); !dynamic {
- g.emit("dst = dst[%d*(%s):]\n", size, lenExpr)
- } else {
- // We can't use shiftDynamic here because we don't have
- // an instance of the dynamic type we can reference here
- // (since the version in this struct is anonymous). Use
- // a typed nil pointer to call SizeBytes() instead.
- g.emit("dst = dst[(*%s)(nil).SizeBytes()*(%s):]\n", t.Name, lenExpr)
- }
- return
- }
-
- g.emit("for idx := 0; idx < %s; idx++ {\n", lenExpr)
- g.inIndent(func() {
- g.marshalScalar(fmt.Sprintf("%s[idx]", g.fieldAccessor(n)), t.Name, "dst")
- })
- g.emit("}\n")
- },
- }.dispatch)
- })
- g.emit("}\n\n")
-
- g.emit("// UnmarshalBytes implements marshal.Marshallable.UnmarshalBytes.\n")
- g.emit("func (%s *%s) UnmarshalBytes(src []byte) {\n", g.r, g.typeName())
- g.inIndent(func() {
- forEachStructField(st, fieldDispatcher{
- primitive: func(n, t *ast.Ident) {
- if n.Name == "_" {
- g.emit("// Padding: var _ %s ~= src[:sizeof(%s)]\n", t.Name, t.Name)
- if len, dynamic := g.scalarSize(t); !dynamic {
- g.shift("src", len)
- } else {
- // We don't have an instance of the dynamic type we can
- // reference here (since the version in this struct is
- // anonymous). Use a typed nil pointer to call
- // SizeBytes() instead.
- g.shiftDynamic("src", fmt.Sprintf("(*%s)(nil)", t.Name))
- g.recordPotentiallyNonPackedField(fmt.Sprintf("(*%s)(nil)", t.Name))
- }
- return
- }
- g.unmarshalScalar(g.fieldAccessor(n), t.Name, "src")
- },
- selector: func(n, tX, tSel *ast.Ident) {
- if n.Name == "_" {
- g.emit("// Padding: %s ~= src[:sizeof(%s.%s)]\n", g.fieldAccessor(n), tX.Name, tSel.Name)
- g.emit("src = src[(*%s.%s)(nil).SizeBytes():]\n", tX.Name, tSel.Name)
- g.recordPotentiallyNonPackedField(fmt.Sprintf("(*%s.%s)(nil)", tX.Name, tSel.Name))
- return
- }
- g.unmarshalScalar(g.fieldAccessor(n), fmt.Sprintf("%s.%s", tX.Name, tSel.Name), "src")
- },
- array: func(n *ast.Ident, a *ast.ArrayType, t *ast.Ident) {
- lenExpr := g.arrayLenExpr(a)
- if n.Name == "_" {
- g.emit("// Padding: ~ copy([%s]%s(%s), src[:sizeof(%s)*%s])\n", lenExpr, t.Name, g.fieldAccessor(n), t.Name, lenExpr)
- if size, dynamic := g.scalarSize(t); !dynamic {
- g.emit("src = src[%d*(%s):]\n", size, lenExpr)
- } else {
- // We can't use shiftDynamic here because we don't have
- // an instance of the dynamic type we can referece here
- // (since the version in this struct is anonymous). Use
- // a typed nil pointer to call SizeBytes() instead.
- g.emit("src = src[(*%s)(nil).SizeBytes()*(%s):]\n", t.Name, lenExpr)
- }
- return
- }
-
- g.emit("for idx := 0; idx < %s; idx++ {\n", lenExpr)
- g.inIndent(func() {
- g.unmarshalScalar(fmt.Sprintf("%s[idx]", g.fieldAccessor(n)), t.Name, "src")
- })
- g.emit("}\n")
- },
- }.dispatch)
- })
- g.emit("}\n\n")
+ // Dynamic types are supposed to manually implement SizeBytes, MarshalBytes
+ // and UnmarshalBytes. The rest of the methos are autogenerated and depend on
+ // the implementation of these three.
+ if !isDynamic {
+ g.emitSizeBytesForStruct(st)
+ g.emitMarshalBytesForStruct(st)
+ g.emitUnmarshalBytesForStruct(st)
+ }
g.emit("// Packed implements marshal.Marshallable.Packed.\n")
g.emit("//go:nosplit\n")
@@ -428,8 +284,171 @@ func (g *interfaceGenerator) emitMarshallableForStruct(st *ast.StructType) {
g.emit("}\n\n")
}
+func (g *interfaceGenerator) emitSizeBytesForStruct(st *ast.StructType) {
+ g.emit("// SizeBytes implements marshal.Marshallable.SizeBytes.\n")
+ g.emit("func (%s *%s) SizeBytes() int {\n", g.r, g.typeName())
+ g.inIndent(func() {
+ primitiveSize := 0
+ var dynamicSizeTerms []string
+
+ forEachStructField(st, fieldDispatcher{
+ primitive: func(_, t *ast.Ident) {
+ if size, dynamic := g.scalarSize(t); !dynamic {
+ primitiveSize += size
+ } else {
+ g.recordUsedMarshallable(t.Name)
+ dynamicSizeTerms = append(dynamicSizeTerms, fmt.Sprintf("(*%s)(nil).SizeBytes()", t.Name))
+ }
+ },
+ selector: func(_, tX, tSel *ast.Ident) {
+ tName := fmt.Sprintf("%s.%s", tX.Name, tSel.Name)
+ g.recordUsedImport(tX.Name)
+ g.recordUsedMarshallable(tName)
+ dynamicSizeTerms = append(dynamicSizeTerms, fmt.Sprintf("(*%s)(nil).SizeBytes()", tName))
+ },
+ array: func(_ *ast.Ident, a *ast.ArrayType, t *ast.Ident) {
+ lenExpr := g.arrayLenExpr(a)
+ if size, dynamic := g.scalarSize(t); !dynamic {
+ dynamicSizeTerms = append(dynamicSizeTerms, fmt.Sprintf("%d*%s", size, lenExpr))
+ } else {
+ g.recordUsedMarshallable(t.Name)
+ dynamicSizeTerms = append(dynamicSizeTerms, fmt.Sprintf("(*%s)(nil).SizeBytes()*%s", t.Name, lenExpr))
+ }
+ },
+ }.dispatch)
+ g.emit("return %d", primitiveSize)
+ if len(dynamicSizeTerms) > 0 {
+ g.incIndent()
+ }
+ {
+ for _, d := range dynamicSizeTerms {
+ g.emitNoIndent(" +\n")
+ g.emit(d)
+ }
+ }
+ if len(dynamicSizeTerms) > 0 {
+ g.decIndent()
+ }
+ })
+ g.emit("\n}\n\n")
+}
+
+func (g *interfaceGenerator) emitMarshalBytesForStruct(st *ast.StructType) {
+ g.emit("// MarshalBytes implements marshal.Marshallable.MarshalBytes.\n")
+ g.emit("func (%s *%s) MarshalBytes(dst []byte) {\n", g.r, g.typeName())
+ g.inIndent(func() {
+ forEachStructField(st, fieldDispatcher{
+ primitive: func(n, t *ast.Ident) {
+ if n.Name == "_" {
+ g.emit("// Padding: dst[:sizeof(%s)] ~= %s(0)\n", t.Name, t.Name)
+ if len, dynamic := g.scalarSize(t); !dynamic {
+ g.shift("dst", len)
+ } else {
+ // We can't use shiftDynamic here because we don't have
+ // an instance of the dynamic type we can reference here
+ // (since the version in this struct is anonymous). Use
+ // a typed nil pointer to call SizeBytes() instead.
+ g.emit("dst = dst[(*%s)(nil).SizeBytes():]\n", t.Name)
+ }
+ return
+ }
+ g.marshalScalar(g.fieldAccessor(n), t.Name, "dst")
+ },
+ selector: func(n, tX, tSel *ast.Ident) {
+ if n.Name == "_" {
+ g.emit("// Padding: dst[:sizeof(%s)] ~= %s(0)\n", tX.Name, tSel.Name)
+ g.emit("dst = dst[(*%s.%s)(nil).SizeBytes():]\n", tX.Name, tSel.Name)
+ return
+ }
+ g.marshalScalar(g.fieldAccessor(n), fmt.Sprintf("%s.%s", tX.Name, tSel.Name), "dst")
+ },
+ array: func(n *ast.Ident, a *ast.ArrayType, t *ast.Ident) {
+ lenExpr := g.arrayLenExpr(a)
+ if n.Name == "_" {
+ g.emit("// Padding: dst[:sizeof(%s)*%s] ~= [%s]%s{0}\n", t.Name, lenExpr, lenExpr, t.Name)
+ if size, dynamic := g.scalarSize(t); !dynamic {
+ g.emit("dst = dst[%d*(%s):]\n", size, lenExpr)
+ } else {
+ // We can't use shiftDynamic here because we don't have
+ // an instance of the dynamic type we can reference here
+ // (since the version in this struct is anonymous). Use
+ // a typed nil pointer to call SizeBytes() instead.
+ g.emit("dst = dst[(*%s)(nil).SizeBytes()*(%s):]\n", t.Name, lenExpr)
+ }
+ return
+ }
+
+ g.emit("for idx := 0; idx < %s; idx++ {\n", lenExpr)
+ g.inIndent(func() {
+ g.marshalScalar(fmt.Sprintf("%s[idx]", g.fieldAccessor(n)), t.Name, "dst")
+ })
+ g.emit("}\n")
+ },
+ }.dispatch)
+ })
+ g.emit("}\n\n")
+}
+
+func (g *interfaceGenerator) emitUnmarshalBytesForStruct(st *ast.StructType) {
+ g.emit("// UnmarshalBytes implements marshal.Marshallable.UnmarshalBytes.\n")
+ g.emit("func (%s *%s) UnmarshalBytes(src []byte) {\n", g.r, g.typeName())
+ g.inIndent(func() {
+ forEachStructField(st, fieldDispatcher{
+ primitive: func(n, t *ast.Ident) {
+ if n.Name == "_" {
+ g.emit("// Padding: var _ %s ~= src[:sizeof(%s)]\n", t.Name, t.Name)
+ if len, dynamic := g.scalarSize(t); !dynamic {
+ g.shift("src", len)
+ } else {
+ // We don't have an instance of the dynamic type we can
+ // reference here (since the version in this struct is
+ // anonymous). Use a typed nil pointer to call
+ // SizeBytes() instead.
+ g.shiftDynamic("src", fmt.Sprintf("(*%s)(nil)", t.Name))
+ g.recordPotentiallyNonPackedField(fmt.Sprintf("(*%s)(nil)", t.Name))
+ }
+ return
+ }
+ g.unmarshalScalar(g.fieldAccessor(n), t.Name, "src")
+ },
+ selector: func(n, tX, tSel *ast.Ident) {
+ if n.Name == "_" {
+ g.emit("// Padding: %s ~= src[:sizeof(%s.%s)]\n", g.fieldAccessor(n), tX.Name, tSel.Name)
+ g.emit("src = src[(*%s.%s)(nil).SizeBytes():]\n", tX.Name, tSel.Name)
+ g.recordPotentiallyNonPackedField(fmt.Sprintf("(*%s.%s)(nil)", tX.Name, tSel.Name))
+ return
+ }
+ g.unmarshalScalar(g.fieldAccessor(n), fmt.Sprintf("%s.%s", tX.Name, tSel.Name), "src")
+ },
+ array: func(n *ast.Ident, a *ast.ArrayType, t *ast.Ident) {
+ lenExpr := g.arrayLenExpr(a)
+ if n.Name == "_" {
+ g.emit("// Padding: ~ copy([%s]%s(%s), src[:sizeof(%s)*%s])\n", lenExpr, t.Name, g.fieldAccessor(n), t.Name, lenExpr)
+ if size, dynamic := g.scalarSize(t); !dynamic {
+ g.emit("src = src[%d*(%s):]\n", size, lenExpr)
+ } else {
+ // We can't use shiftDynamic here because we don't have
+ // an instance of the dynamic type we can referece here
+ // (since the version in this struct is anonymous). Use
+ // a typed nil pointer to call SizeBytes() instead.
+ g.emit("src = src[(*%s)(nil).SizeBytes()*(%s):]\n", t.Name, lenExpr)
+ }
+ return
+ }
+
+ g.emit("for idx := 0; idx < %s; idx++ {\n", lenExpr)
+ g.inIndent(func() {
+ g.unmarshalScalar(fmt.Sprintf("%s[idx]", g.fieldAccessor(n)), t.Name, "src")
+ })
+ g.emit("}\n")
+ },
+ }.dispatch)
+ })
+ g.emit("}\n\n")
+}
+
func (g *interfaceGenerator) emitMarshallableSliceForStruct(st *ast.StructType, slice *sliceAPI) {
- thisPacked := g.isStructPacked(st)
+ thisPacked := g.isStructPacked(st, false /* isDynamic */)
if slice.inner {
abortAt(g.f.Position(slice.comment.Slash), fmt.Sprintf("The ':inner' argument to '+marshal slice:%s:inner' is only applicable to newtypes on primitives. Remove it from this struct declaration.", slice.ident))
diff --git a/tools/go_marshal/gomarshal/generator_tests.go b/tools/go_marshal/gomarshal/generator_tests.go
index 6cf00843f..ca3e15c16 100644
--- a/tools/go_marshal/gomarshal/generator_tests.go
+++ b/tools/go_marshal/gomarshal/generator_tests.go
@@ -216,12 +216,16 @@ func (g *testGenerator) emitTestSizeBytesOnTypedNilPtr() {
})
}
-func (g *testGenerator) emitTests(slice *sliceAPI) {
+func (g *testGenerator) emitTests(slice *sliceAPI, isDynamic bool) {
g.emitTestNonZeroSize()
g.emitTestSuspectAlignment()
- g.emitTestMarshalUnmarshalPreservesData()
- g.emitTestWriteToUnmarshalPreservesData()
- g.emitTestSizeBytesOnTypedNilPtr()
+ if !isDynamic {
+ // Do not test these for dynamic structs because they violate some
+ // assumptions that these tests make.
+ g.emitTestMarshalUnmarshalPreservesData()
+ g.emitTestWriteToUnmarshalPreservesData()
+ g.emitTestSizeBytesOnTypedNilPtr()
+ }
if slice != nil {
g.emitTestMarshalUnmarshalSlicePreservesData(slice)
diff --git a/tools/go_marshal/test/BUILD b/tools/go_marshal/test/BUILD
index 4b27773c2..cb2d4e6e3 100644
--- a/tools/go_marshal/test/BUILD
+++ b/tools/go_marshal/test/BUILD
@@ -26,7 +26,10 @@ go_library(
srcs = ["test.go"],
marshal = True,
visibility = ["//tools/go_marshal/test:__subpackages__"],
- deps = ["//tools/go_marshal/test/external"],
+ deps = [
+ "//pkg/marshal/primitive",
+ "//tools/go_marshal/test/external",
+ ],
)
go_test(
@@ -36,6 +39,7 @@ go_test(
deps = [
":test",
"//pkg/marshal",
+ "//pkg/marshal/primitive",
"//pkg/syserror",
"//pkg/usermem",
"//tools/go_marshal/analysis",
diff --git a/tools/go_marshal/test/marshal_test.go b/tools/go_marshal/test/marshal_test.go
index a00f9a684..b0091dc64 100644
--- a/tools/go_marshal/test/marshal_test.go
+++ b/tools/go_marshal/test/marshal_test.go
@@ -28,6 +28,7 @@ import (
"github.com/google/go-cmp/cmp"
"gvisor.dev/gvisor/pkg/marshal"
+ "gvisor.dev/gvisor/pkg/marshal/primitive"
"gvisor.dev/gvisor/pkg/syserror"
"gvisor.dev/gvisor/pkg/usermem"
"gvisor.dev/gvisor/tools/go_marshal/analysis"
@@ -513,3 +514,21 @@ func TestLimitedSliceMarshalling(t *testing.T) {
})
}
}
+
+func TestDynamicType(t *testing.T) {
+ t12 := test.Type12Dynamic{
+ X: 32,
+ Y: []primitive.Int64{5, 6, 7},
+ }
+
+ var m marshal.Marshallable
+ m = &t12 // Ensure that all methods were generated.
+ b := make([]byte, m.SizeBytes())
+ m.MarshalBytes(b)
+
+ var res test.Type12Dynamic
+ res.UnmarshalBytes(b)
+ if !reflect.DeepEqual(t12, res) {
+ t.Errorf("dynamic type is not same after marshalling and unmarshalling: before = %+v, after = %+v", t12, res)
+ }
+}
diff --git a/tools/go_marshal/test/test.go b/tools/go_marshal/test/test.go
index e7e3ed74a..b8eb989d9 100644
--- a/tools/go_marshal/test/test.go
+++ b/tools/go_marshal/test/test.go
@@ -16,6 +16,8 @@
package test
import (
+ "gvisor.dev/gvisor/pkg/marshal/primitive"
+
// We're intentionally using a package name alias here even though it's not
// necessary to test the code generator's ability to handle package aliases.
ex "gvisor.dev/gvisor/tools/go_marshal/test/external"
@@ -198,3 +200,36 @@ type Type11 struct {
ex.External
y int64
}
+
+// Type12Dynamic is a dynamically sized struct which depends on the autogenerator
+// to generate some Marshallable methods for it.
+//
+// +marshal dynamic
+type Type12Dynamic struct {
+ X primitive.Int64
+ Y []primitive.Int64
+}
+
+// SizeBytes implements marshal.Marshallable.SizeBytes.
+func (t *Type12Dynamic) SizeBytes() int {
+ return (len(t.Y) * 8) + t.X.SizeBytes()
+}
+
+// MarshalBytes implements marshal.Marshallable.MarshalBytes.
+func (t *Type12Dynamic) MarshalBytes(dst []byte) {
+ t.X.MarshalBytes(dst)
+ dst = dst[t.X.SizeBytes():]
+ for i, x := range t.Y {
+ x.MarshalBytes(dst[i*8 : (i+1)*8])
+ }
+}
+
+// UnmarshalBytes implements marshal.Marshallable.UnmarshalBytes.
+func (t *Type12Dynamic) UnmarshalBytes(src []byte) {
+ t.X.UnmarshalBytes(src)
+ for i := t.X.SizeBytes(); i < len(src); i += 8 {
+ var x primitive.Int64
+ x.UnmarshalBytes(src[i:])
+ t.Y = append(t.Y, x)
+ }
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-18 12:22:38 +0000