diff options
Diffstat (limited to 'pkg/buffer')
-rw-r--r-- | pkg/buffer/BUILD | 39 | ||||
-rwxr-xr-x[-rw-r--r--] | pkg/buffer/buffer.go | 0 | ||||
-rwxr-xr-x | pkg/buffer/buffer_list.go | 186 | ||||
-rwxr-xr-x | pkg/buffer/buffer_state_autogen.go | 70 | ||||
-rwxr-xr-x[-rw-r--r--] | pkg/buffer/safemem.go | 0 | ||||
-rwxr-xr-x[-rw-r--r--] | pkg/buffer/view.go | 0 | ||||
-rw-r--r-- | pkg/buffer/view_test.go | 233 | ||||
-rwxr-xr-x[-rw-r--r--] | pkg/buffer/view_unsafe.go | 0 |
8 files changed, 256 insertions, 272 deletions
diff --git a/pkg/buffer/BUILD b/pkg/buffer/BUILD deleted file mode 100644 index a77a3beea..000000000 --- a/pkg/buffer/BUILD +++ /dev/null @@ -1,39 +0,0 @@ -load("//tools:defs.bzl", "go_library", "go_test") -load("//tools/go_generics:defs.bzl", "go_template_instance") - -package(licenses = ["notice"]) - -go_template_instance( - name = "buffer_list", - out = "buffer_list.go", - package = "buffer", - prefix = "buffer", - template = "//pkg/ilist:generic_list", - types = { - "Element": "*Buffer", - "Linker": "*Buffer", - }, -) - -go_library( - name = "buffer", - srcs = [ - "buffer.go", - "buffer_list.go", - "safemem.go", - "view.go", - "view_unsafe.go", - ], - visibility = ["//visibility:public"], - deps = [ - "//pkg/log", - "//pkg/safemem", - ], -) - -go_test( - name = "buffer_test", - size = "small", - srcs = ["view_test.go"], - library = ":buffer", -) diff --git a/pkg/buffer/buffer.go b/pkg/buffer/buffer.go index d5f64609b..d5f64609b 100644..100755 --- a/pkg/buffer/buffer.go +++ b/pkg/buffer/buffer.go diff --git a/pkg/buffer/buffer_list.go b/pkg/buffer/buffer_list.go new file mode 100755 index 000000000..acada55a0 --- /dev/null +++ b/pkg/buffer/buffer_list.go @@ -0,0 +1,186 @@ +package buffer + +// ElementMapper provides an identity mapping by default. +// +// This can be replaced to provide a struct that maps elements to linker +// objects, if they are not the same. An ElementMapper is not typically +// required if: Linker is left as is, Element is left as is, or Linker and +// Element are the same type. +type bufferElementMapper struct{} + +// linkerFor maps an Element to a Linker. +// +// This default implementation should be inlined. +// +//go:nosplit +func (bufferElementMapper) linkerFor(elem *Buffer) *Buffer { return elem } + +// List is an intrusive list. Entries can be added to or removed from the list +// in O(1) time and with no additional memory allocations. +// +// The zero value for List is an empty list ready to use. +// +// To iterate over a list (where l is a List): +// for e := l.Front(); e != nil; e = e.Next() { +// // do something with e. +// } +// +// +stateify savable +type bufferList struct { + head *Buffer + tail *Buffer +} + +// Reset resets list l to the empty state. +func (l *bufferList) Reset() { + l.head = nil + l.tail = nil +} + +// Empty returns true iff the list is empty. +func (l *bufferList) Empty() bool { + return l.head == nil +} + +// Front returns the first element of list l or nil. +func (l *bufferList) Front() *Buffer { + return l.head +} + +// Back returns the last element of list l or nil. +func (l *bufferList) Back() *Buffer { + return l.tail +} + +// PushFront inserts the element e at the front of list l. +func (l *bufferList) PushFront(e *Buffer) { + linker := bufferElementMapper{}.linkerFor(e) + linker.SetNext(l.head) + linker.SetPrev(nil) + + if l.head != nil { + bufferElementMapper{}.linkerFor(l.head).SetPrev(e) + } else { + l.tail = e + } + + l.head = e +} + +// PushBack inserts the element e at the back of list l. +func (l *bufferList) PushBack(e *Buffer) { + linker := bufferElementMapper{}.linkerFor(e) + linker.SetNext(nil) + linker.SetPrev(l.tail) + + if l.tail != nil { + bufferElementMapper{}.linkerFor(l.tail).SetNext(e) + } else { + l.head = e + } + + l.tail = e +} + +// PushBackList inserts list m at the end of list l, emptying m. +func (l *bufferList) PushBackList(m *bufferList) { + if l.head == nil { + l.head = m.head + l.tail = m.tail + } else if m.head != nil { + bufferElementMapper{}.linkerFor(l.tail).SetNext(m.head) + bufferElementMapper{}.linkerFor(m.head).SetPrev(l.tail) + + l.tail = m.tail + } + + m.head = nil + m.tail = nil +} + +// InsertAfter inserts e after b. +func (l *bufferList) InsertAfter(b, e *Buffer) { + bLinker := bufferElementMapper{}.linkerFor(b) + eLinker := bufferElementMapper{}.linkerFor(e) + + a := bLinker.Next() + + eLinker.SetNext(a) + eLinker.SetPrev(b) + bLinker.SetNext(e) + + if a != nil { + bufferElementMapper{}.linkerFor(a).SetPrev(e) + } else { + l.tail = e + } +} + +// InsertBefore inserts e before a. +func (l *bufferList) InsertBefore(a, e *Buffer) { + aLinker := bufferElementMapper{}.linkerFor(a) + eLinker := bufferElementMapper{}.linkerFor(e) + + b := aLinker.Prev() + eLinker.SetNext(a) + eLinker.SetPrev(b) + aLinker.SetPrev(e) + + if b != nil { + bufferElementMapper{}.linkerFor(b).SetNext(e) + } else { + l.head = e + } +} + +// Remove removes e from l. +func (l *bufferList) Remove(e *Buffer) { + linker := bufferElementMapper{}.linkerFor(e) + prev := linker.Prev() + next := linker.Next() + + if prev != nil { + bufferElementMapper{}.linkerFor(prev).SetNext(next) + } else { + l.head = next + } + + if next != nil { + bufferElementMapper{}.linkerFor(next).SetPrev(prev) + } else { + l.tail = prev + } + + linker.SetNext(nil) + linker.SetPrev(nil) +} + +// Entry is a default implementation of Linker. Users can add anonymous fields +// of this type to their structs to make them automatically implement the +// methods needed by List. +// +// +stateify savable +type bufferEntry struct { + next *Buffer + prev *Buffer +} + +// Next returns the entry that follows e in the list. +func (e *bufferEntry) Next() *Buffer { + return e.next +} + +// Prev returns the entry that precedes e in the list. +func (e *bufferEntry) Prev() *Buffer { + return e.prev +} + +// SetNext assigns 'entry' as the entry that follows e in the list. +func (e *bufferEntry) SetNext(elem *Buffer) { + e.next = elem +} + +// SetPrev assigns 'entry' as the entry that precedes e in the list. +func (e *bufferEntry) SetPrev(elem *Buffer) { + e.prev = elem +} diff --git a/pkg/buffer/buffer_state_autogen.go b/pkg/buffer/buffer_state_autogen.go new file mode 100755 index 000000000..9565eb6fa --- /dev/null +++ b/pkg/buffer/buffer_state_autogen.go @@ -0,0 +1,70 @@ +// automatically generated by stateify. + +package buffer + +import ( + "gvisor.dev/gvisor/pkg/state" +) + +func (x *Buffer) beforeSave() {} +func (x *Buffer) save(m state.Map) { + x.beforeSave() + m.Save("data", &x.data) + m.Save("read", &x.read) + m.Save("write", &x.write) + m.Save("bufferEntry", &x.bufferEntry) +} + +func (x *Buffer) afterLoad() {} +func (x *Buffer) load(m state.Map) { + m.Load("data", &x.data) + m.Load("read", &x.read) + m.Load("write", &x.write) + m.Load("bufferEntry", &x.bufferEntry) +} + +func (x *bufferList) beforeSave() {} +func (x *bufferList) save(m state.Map) { + x.beforeSave() + m.Save("head", &x.head) + m.Save("tail", &x.tail) +} + +func (x *bufferList) afterLoad() {} +func (x *bufferList) load(m state.Map) { + m.Load("head", &x.head) + m.Load("tail", &x.tail) +} + +func (x *bufferEntry) beforeSave() {} +func (x *bufferEntry) save(m state.Map) { + x.beforeSave() + m.Save("next", &x.next) + m.Save("prev", &x.prev) +} + +func (x *bufferEntry) afterLoad() {} +func (x *bufferEntry) load(m state.Map) { + m.Load("next", &x.next) + m.Load("prev", &x.prev) +} + +func (x *View) beforeSave() {} +func (x *View) save(m state.Map) { + x.beforeSave() + m.Save("data", &x.data) + m.Save("size", &x.size) +} + +func (x *View) afterLoad() {} +func (x *View) load(m state.Map) { + m.Load("data", &x.data) + m.Load("size", &x.size) +} + +func init() { + state.Register("pkg/buffer.Buffer", (*Buffer)(nil), state.Fns{Save: (*Buffer).save, Load: (*Buffer).load}) + state.Register("pkg/buffer.bufferList", (*bufferList)(nil), state.Fns{Save: (*bufferList).save, Load: (*bufferList).load}) + state.Register("pkg/buffer.bufferEntry", (*bufferEntry)(nil), state.Fns{Save: (*bufferEntry).save, Load: (*bufferEntry).load}) + state.Register("pkg/buffer.View", (*View)(nil), state.Fns{Save: (*View).save, Load: (*View).load}) +} diff --git a/pkg/buffer/safemem.go b/pkg/buffer/safemem.go index 071aaa488..071aaa488 100644..100755 --- a/pkg/buffer/safemem.go +++ b/pkg/buffer/safemem.go diff --git a/pkg/buffer/view.go b/pkg/buffer/view.go index 00fc11e9c..00fc11e9c 100644..100755 --- a/pkg/buffer/view.go +++ b/pkg/buffer/view.go diff --git a/pkg/buffer/view_test.go b/pkg/buffer/view_test.go deleted file mode 100644 index 37e652f16..000000000 --- a/pkg/buffer/view_test.go +++ /dev/null @@ -1,233 +0,0 @@ -// Copyright 2020 The gVisor Authors. -// -// Licensed under the Apache License, Version 2.0 (the "License"); -// you may not use this file except in compliance with the License. -// You may obtain a copy of the License at -// -// http://www.apache.org/licenses/LICENSE-2.0 -// -// Unless required by applicable law or agreed to in writing, software -// distributed under the License is distributed on an "AS IS" BASIS, -// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -// See the License for the specific language governing permissions and -// limitations under the License. - -package buffer - -import ( - "bytes" - "strings" - "testing" -) - -func TestView(t *testing.T) { - testCases := []struct { - name string - input string - output string - ops []func(*View) - }{ - // Prepend. - { - name: "prepend", - input: "world", - ops: []func(*View){ - func(v *View) { - v.Prepend([]byte("hello ")) - }, - }, - output: "hello world", - }, - { - name: "prepend fill", - input: strings.Repeat("1", bufferSize-1), - ops: []func(*View){ - func(v *View) { - v.Prepend([]byte("0")) - }, - }, - output: "0" + strings.Repeat("1", bufferSize-1), - }, - { - name: "prepend overflow", - input: strings.Repeat("1", bufferSize), - ops: []func(*View){ - func(v *View) { - v.Prepend([]byte("0")) - }, - }, - output: "0" + strings.Repeat("1", bufferSize), - }, - { - name: "prepend multiple buffers", - input: strings.Repeat("1", bufferSize-1), - ops: []func(*View){ - func(v *View) { - v.Prepend([]byte(strings.Repeat("0", bufferSize*3))) - }, - }, - output: strings.Repeat("0", bufferSize*3) + strings.Repeat("1", bufferSize-1), - }, - - // Append. - { - name: "append", - input: "hello", - ops: []func(*View){ - func(v *View) { - v.Append([]byte(" world")) - }, - }, - output: "hello world", - }, - { - name: "append fill", - input: strings.Repeat("1", bufferSize-1), - ops: []func(*View){ - func(v *View) { - v.Append([]byte("0")) - }, - }, - output: strings.Repeat("1", bufferSize-1) + "0", - }, - { - name: "append overflow", - input: strings.Repeat("1", bufferSize), - ops: []func(*View){ - func(v *View) { - v.Append([]byte("0")) - }, - }, - output: strings.Repeat("1", bufferSize) + "0", - }, - { - name: "append multiple buffers", - input: strings.Repeat("1", bufferSize-1), - ops: []func(*View){ - func(v *View) { - v.Append([]byte(strings.Repeat("0", bufferSize*3))) - }, - }, - output: strings.Repeat("1", bufferSize-1) + strings.Repeat("0", bufferSize*3), - }, - - // Truncate. - { - name: "truncate", - input: "hello world", - ops: []func(*View){ - func(v *View) { - v.Truncate(5) - }, - }, - output: "hello", - }, - { - name: "truncate multiple buffers", - input: strings.Repeat("1", bufferSize*2), - ops: []func(*View){ - func(v *View) { - v.Truncate(bufferSize*2 - 1) - }, - }, - output: strings.Repeat("1", bufferSize*2-1), - }, - { - name: "truncate multiple buffers to one buffer", - input: strings.Repeat("1", bufferSize*2), - ops: []func(*View){ - func(v *View) { - v.Truncate(5) - }, - }, - output: "11111", - }, - - // TrimFront. - { - name: "trim", - input: "hello world", - ops: []func(*View){ - func(v *View) { - v.TrimFront(6) - }, - }, - output: "world", - }, - { - name: "trim multiple buffers", - input: strings.Repeat("1", bufferSize*2), - ops: []func(*View){ - func(v *View) { - v.TrimFront(1) - }, - }, - output: strings.Repeat("1", bufferSize*2-1), - }, - { - name: "trim multiple buffers to one buffer", - input: strings.Repeat("1", bufferSize*2), - ops: []func(*View){ - func(v *View) { - v.TrimFront(bufferSize*2 - 1) - }, - }, - output: "1", - }, - - // Grow. - { - name: "grow", - input: "hello world", - ops: []func(*View){ - func(v *View) { - v.Grow(1, true) - }, - }, - output: "hello world", - }, - { - name: "grow from zero", - ops: []func(*View){ - func(v *View) { - v.Grow(1024, true) - }, - }, - output: strings.Repeat("\x00", 1024), - }, - { - name: "grow from non-zero", - input: strings.Repeat("1", bufferSize), - ops: []func(*View){ - func(v *View) { - v.Grow(bufferSize*2, true) - }, - }, - output: strings.Repeat("1", bufferSize) + strings.Repeat("\x00", bufferSize), - }, - } - - for _, tc := range testCases { - t.Run(tc.name, func(t *testing.T) { - // Construct the new view. - var view View - view.Append([]byte(tc.input)) - - // Run all operations. - for _, op := range tc.ops { - op(&view) - } - - // Flatten and validate. - out := view.Flatten() - if !bytes.Equal([]byte(tc.output), out) { - t.Errorf("expected %q, got %q", tc.output, string(out)) - } - - // Ensure the size is correct. - if len(out) != int(view.Size()) { - t.Errorf("size is wrong: expected %d, got %d", len(out), view.Size()) - } - }) - } -} diff --git a/pkg/buffer/view_unsafe.go b/pkg/buffer/view_unsafe.go index d1ef39b26..d1ef39b26 100644..100755 --- a/pkg/buffer/view_unsafe.go +++ b/pkg/buffer/view_unsafe.go |