go
/
gvisor
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

Simplify {Un}MarshalUnsafeSlice method signatures. 

Earlier this function was returning (int, error) much like the Copy{In/Out}
methods. The returned error was always nil. The returned int was never used.

Instead make it returned the shifted buffer which is more useful.
Updates #6450

PiperOrigin-RevId: 408268327
This commit is contained in:
Ayush Ranjan 2021-11-08 00:37:24 -08:00 committed by gVisor bot
parent ce4f4283ba
commit 4622e17bcc
5 changed files with 42 additions and 79 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

52
pkg/lisafs/message.go
View File

@ -307,11 +307,7 @@ func (m *MountResp) MarshalBytes(dst []byte) []byte {
dst = m.MaxMessageSize.MarshalUnsafe(dst)
numSupported := primitive.Uint16(len(m.SupportedMs))
dst = numSupported.MarshalBytes(dst)
n, err := MarshalUnsafeMIDSlice(m.SupportedMs, dst)
if err != nil {
panic(err)
}
return dst[n:]
return MarshalUnsafeMIDSlice(m.SupportedMs, dst)
}
// UnmarshalBytes implements marshal.Marshallable.UnmarshalBytes.
@ -320,12 +316,12 @@ func (m *MountResp) UnmarshalBytes(src []byte) []byte {
src = m.MaxMessageSize.UnmarshalUnsafe(src)
var numSupported primitive.Uint16
src = numSupported.UnmarshalBytes(src)
m.SupportedMs = make([]MID, numSupported)
n, err := UnmarshalUnsafeMIDSlice(m.SupportedMs, src)
if err != nil {
panic(err)
if cap(m.SupportedMs) < int(numSupported) {
m.SupportedMs = make([]MID, numSupported)
} else {
m.SupportedMs = m.SupportedMs[:numSupported]
}
return src[n:]
return UnmarshalUnsafeMIDSlice(m.SupportedMs, src)
}
// ChannelResp is the response to the create channel request.
@ -440,11 +436,7 @@ func (w *WalkResp) MarshalBytes(dst []byte) []byte {
numInodes := primitive.Uint32(len(w.Inodes))
dst = numInodes.MarshalUnsafe(dst)
n, err := MarshalUnsafeInodeSlice(w.Inodes, dst)
if err != nil {
panic(err)
}
return dst[n:]
return MarshalUnsafeInodeSlice(w.Inodes, dst)
}
// UnmarshalBytes implements marshal.Marshallable.UnmarshalBytes.
@ -459,11 +451,7 @@ func (w *WalkResp) UnmarshalBytes(src []byte) []byte {
} else {
w.Inodes = w.Inodes[:numInodes]
}
n, err := UnmarshalUnsafeInodeSlice(w.Inodes, src)
if err != nil {
panic(err)
}
return src[n:]
return UnmarshalUnsafeInodeSlice(w.Inodes, src)
}
// WalkStatResp is used to communicate stat results for WalkStat.
@ -481,11 +469,7 @@ func (w *WalkStatResp) MarshalBytes(dst []byte) []byte {
numStats := primitive.Uint32(len(w.Stats))
dst = numStats.MarshalUnsafe(dst)
n, err := linux.MarshalUnsafeStatxSlice(w.Stats, dst)
if err != nil {
panic(err)
}
return dst[n:]
return linux.MarshalUnsafeStatxSlice(w.Stats, dst)
}
// UnmarshalBytes implements marshal.Marshallable.UnmarshalBytes.
@ -498,11 +482,7 @@ func (w *WalkStatResp) UnmarshalBytes(src []byte) []byte {
} else {
w.Stats = w.Stats[:numStats]
}
n, err := linux.UnmarshalUnsafeStatxSlice(w.Stats, src)
if err != nil {
panic(err)
}
return src[n:]
return linux.UnmarshalUnsafeStatxSlice(w.Stats, src)
}
// OpenAtReq is used to open existing FDs with the specified flags.
@ -578,11 +558,7 @@ func (f *FdArray) SizeBytes() int {
func (f *FdArray) MarshalBytes(dst []byte) []byte {
arrLen := primitive.Uint32(len(*f))
dst = arrLen.MarshalUnsafe(dst)
n, err := MarshalUnsafeFDIDSlice(*f, dst)
if err != nil {
panic(err)
}
return dst[n:]
return MarshalUnsafeFDIDSlice(*f, dst)
}
// UnmarshalBytes implements marshal.Marshallable.UnmarshalBytes.
@ -594,11 +570,7 @@ func (f *FdArray) UnmarshalBytes(src []byte) []byte {
} else {
*f = (*f)[:arrLen]
}
n, err := UnmarshalUnsafeFDIDSlice(*f, src)
if err != nil {
panic(err)
}
return src[n:]
return UnmarshalUnsafeFDIDSlice(*f, src)
}
// CloseReq is used to close(2) FDs.

12
pkg/lisafs/sample_message.go
View File

@ -55,22 +55,14 @@ func (m *MsgDynamic) SizeBytes() int {
// MarshalBytes implements marshal.Marshallable.MarshalBytes.
func (m *MsgDynamic) MarshalBytes(dst []byte) []byte {
dst = m.N.MarshalUnsafe(dst)
n, err := MarshalUnsafeMsg1Slice(m.Arr, dst)
if err != nil {
panic(err)
}
return dst[n:]
return MarshalUnsafeMsg1Slice(m.Arr, dst)
}
// UnmarshalBytes implements marshal.Marshallable.UnmarshalBytes.
func (m *MsgDynamic) UnmarshalBytes(src []byte) []byte {
src = m.N.UnmarshalUnsafe(src)
m.Arr = make([]MsgSimple, m.N)
n, err := UnmarshalUnsafeMsg1Slice(m.Arr, src)
if err != nil {
panic(err)
}
return src[n:]
return UnmarshalUnsafeMsg1Slice(m.Arr, src)
}
// Randomize randomizes the contents of m.

4
pkg/marshal/marshal.go
View File

@ -150,13 +150,13 @@ type Marshallable interface {
// // might be more efficient that repeatedly calling Foo.MarshalUnsafe
// // over a []Foo in a loop if the type is Packed.
// // Preconditions: dst must be at least len(src)*Foo.SizeBytes() in length.
// func MarshalUnsafeFooSlice(src []Foo, dst []byte) (int, error) { ... }
// func MarshalUnsafeFooSlice(src []Foo, dst []byte) []byte { ... }
//
// // UnmarshalUnsafeFooSlice is like Foo.UnmarshalUnsafe, buf for a []Foo. It
// // might be more efficient that repeatedly calling Foo.UnmarshalUnsafe
// // over a []Foo in a loop if the type is Packed.
// // Preconditions: src must be at least len(dst)*Foo.SizeBytes() in length.
// func UnmarshalUnsafeFooSlice(dst []Foo, src []byte) (int, error) { ... }
// func UnmarshalUnsafeFooSlice(dst []Foo, src []byte) []byte { ... }
//
// // CopyFooSliceIn copies in a slice of Foo objects from the task's memory.
// func CopyFooSliceIn(cc marshal.CopyContext, addr hostarch.Addr, dst []Foo) (int, error) { ... }

20
tools/go_marshal/gomarshal/generator_interfaces_primitive_newtype.go
View File

@ -264,36 +264,36 @@ func (g *interfaceGenerator) emitMarshallableSliceForPrimitiveNewtype(nt *ast.Id
g.emit("}\n\n")
g.emit("// MarshalUnsafe%s is like %s.MarshalUnsafe, but for a []%s.\n", slice.ident, g.typeName(), g.typeName())
g.emit("func MarshalUnsafe%s(src []%s, dst []byte) (int, error) {\n", slice.ident, g.typeName())
g.emit("func MarshalUnsafe%s(src []%s, dst []byte) []byte {\n", slice.ident, g.typeName())
g.inIndent(func() {
g.emit("count := len(src)\n")
g.emit("if count == 0 {\n")
g.inIndent(func() {
g.emit("return 0, nil\n")
g.emit("return dst\n")
})
g.emit("}\n")
g.emit("size := (*%s)(nil).SizeBytes()\n\n", g.typeName())
g.emit("dst = dst[:size*count]\n")
g.emit("gohacks.Memmove(unsafe.Pointer(&dst[0]), unsafe.Pointer(&src[0]), uintptr(len(dst)))\n")
g.emit("return size*count, nil\n")
g.emit("buf := dst[:size*count]\n")
g.emit("gohacks.Memmove(unsafe.Pointer(&buf[0]), unsafe.Pointer(&src[0]), uintptr(len(buf)))\n")
g.emit("return dst[size*count:]\n")
})
g.emit("}\n\n")
g.emit("// UnmarshalUnsafe%s is like %s.UnmarshalUnsafe, but for a []%s.\n", slice.ident, g.typeName(), g.typeName())
g.emit("func UnmarshalUnsafe%s(dst []%s, src []byte) (int, error) {\n", slice.ident, g.typeName())
g.emit("func UnmarshalUnsafe%s(dst []%s, src []byte) []byte {\n", slice.ident, g.typeName())
g.inIndent(func() {
g.emit("count := len(dst)\n")
g.emit("if count == 0 {\n")
g.inIndent(func() {
g.emit("return 0, nil\n")
g.emit("return src\n")
})
g.emit("}\n")
g.emit("size := (*%s)(nil).SizeBytes()\n\n", g.typeName())
g.emit("src = src[:(size*count)]\n")
g.emit("gohacks.Memmove(unsafe.Pointer(&dst[0]), unsafe.Pointer(&src[0]), uintptr(len(src)))\n")
g.emit("return size*count, nil\n")
g.emit("buf := src[:size*count]\n")
g.emit("gohacks.Memmove(unsafe.Pointer(&dst[0]), unsafe.Pointer(&buf[0]), uintptr(len(buf)))\n")
g.emit("return src[size*count:]\n")
})
g.emit("}\n\n")
}

33
tools/go_marshal/gomarshal/generator_interfaces_struct.go
View File

@ -545,15 +545,14 @@ func (g *interfaceGenerator) emitMarshallableSliceForStruct(st *ast.StructType,
g.emit("}\n\n")
g.emit("// MarshalUnsafe%s is like %s.MarshalUnsafe, but for a []%s.\n", slice.ident, g.typeName(), g.typeName())
g.emit("func MarshalUnsafe%s(src []%s, dst []byte) (int, error) {\n", slice.ident, g.typeName())
g.emit("func MarshalUnsafe%s(src []%s, dst []byte) []byte {\n", slice.ident, g.typeName())
g.inIndent(func() {
g.emit("count := len(src)\n")
g.emit("if count == 0 {\n")
g.inIndent(func() {
g.emit("return 0, nil\n")
g.emit("return dst\n")
})
g.emit("}\n")
g.emit("size := (*%s)(nil).SizeBytes()\n\n", g.typeName())
g.emit("}\n\n")
fallback := func() {
g.emit("// Type %s doesn't have a packed layout in memory, fall back to MarshalBytes.\n", g.typeName())
@ -562,7 +561,7 @@ func (g *interfaceGenerator) emitMarshallableSliceForStruct(st *ast.StructType,
g.emit("dst = src[idx].MarshalBytes(dst)\n")
})
g.emit("}\n")
g.emit("return size * count, nil\n")
g.emit("return dst\n")
}
if thisPacked {
g.recordUsedImport("reflect")
@ -574,9 +573,10 @@ func (g *interfaceGenerator) emitMarshallableSliceForStruct(st *ast.StructType,
g.inIndent(fallback)
g.emit("}\n\n")
}
g.emit("dst = dst[:size*count]\n")
g.emit("gohacks.Memmove(unsafe.Pointer(&dst[0]), unsafe.Pointer(&src[0]), uintptr(len(dst)))\n")
g.emit("return size * count, nil\n")
g.emit("size := (*%s)(nil).SizeBytes()\n", g.typeName())
g.emit("buf := dst[:size*count]\n")
g.emit("gohacks.Memmove(unsafe.Pointer(&buf[0]), unsafe.Pointer(&src[0]), uintptr(len(buf)))\n")
g.emit("return dst[size*count:]\n")
} else {
fallback()
}
@ -584,15 +584,14 @@ func (g *interfaceGenerator) emitMarshallableSliceForStruct(st *ast.StructType,
g.emit("}\n\n")
g.emit("// UnmarshalUnsafe%s is like %s.UnmarshalUnsafe, but for a []%s.\n", slice.ident, g.typeName(), g.typeName())
g.emit("func UnmarshalUnsafe%s(dst []%s, src []byte) (int, error) {\n", slice.ident, g.typeName())
g.emit("func UnmarshalUnsafe%s(dst []%s, src []byte) []byte {\n", slice.ident, g.typeName())
g.inIndent(func() {
g.emit("count := len(dst)\n")
g.emit("if count == 0 {\n")
g.inIndent(func() {
g.emit("return 0, nil\n")
g.emit("return src\n")
})
g.emit("}\n")
g.emit("size := (*%s)(nil).SizeBytes()\n\n", g.typeName())
g.emit("}\n\n")
fallback := func() {
g.emit("// Type %s doesn't have a packed layout in memory, fall back to UnmarshalBytes.\n", g.typeName())
@ -601,7 +600,7 @@ func (g *interfaceGenerator) emitMarshallableSliceForStruct(st *ast.StructType,
g.emit("src = dst[idx].UnmarshalBytes(src)\n")
})
g.emit("}\n")
g.emit("return size * count, nil\n")
g.emit("return src\n")
}
if thisPacked {
g.recordUsedImport("gohacks")
@ -613,10 +612,10 @@ func (g *interfaceGenerator) emitMarshallableSliceForStruct(st *ast.StructType,
g.emit("}\n\n")
}
g.emit("src = src[:(size*count)]\n")
g.emit("gohacks.Memmove(unsafe.Pointer(&dst[0]), unsafe.Pointer(&src[0]), uintptr(len(src)))\n")
g.emit("return count*size, nil\n")
g.emit("size := (*%s)(nil).SizeBytes()\n", g.typeName())
g.emit("buf := src[:size*count]\n")
g.emit("gohacks.Memmove(unsafe.Pointer(&dst[0]), unsafe.Pointer(&buf[0]), uintptr(len(buf)))\n")
g.emit("return src[size*count:]\n")
} else {
fallback()
}