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-rw-r--r--pkg/buffer/BUILD50
-rw-r--r--pkg/buffer/buffer_list.go221
-rw-r--r--pkg/buffer/buffer_state_autogen.go153
-rw-r--r--pkg/buffer/buffer_unsafe_state_autogen.go3
-rw-r--r--pkg/buffer/pool_test.go51
-rw-r--r--pkg/buffer/safemem_test.go172
-rw-r--r--pkg/buffer/view_test.go544
7 files changed, 377 insertions, 817 deletions
diff --git a/pkg/buffer/BUILD b/pkg/buffer/BUILD
deleted file mode 100644
index 1186f788e..000000000
--- a/pkg/buffer/BUILD
+++ /dev/null
@@ -1,50 +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",
- "pool.go",
- "safemem.go",
- "view.go",
- "view_unsafe.go",
- ],
- visibility = ["//visibility:public"],
- deps = [
- "//pkg/context",
- "//pkg/log",
- "//pkg/safemem",
- "//pkg/usermem",
- ],
-)
-
-go_test(
- name = "buffer_test",
- size = "small",
- srcs = [
- "pool_test.go",
- "safemem_test.go",
- "view_test.go",
- ],
- library = ":buffer",
- deps = [
- "//pkg/safemem",
- "//pkg/state",
- ],
-)
diff --git a/pkg/buffer/buffer_list.go b/pkg/buffer/buffer_list.go
new file mode 100644
index 000000000..6b5bea3fc
--- /dev/null
+++ b/pkg/buffer/buffer_list.go
@@ -0,0 +1,221 @@
+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.
+//
+//go:nosplit
+func (l *bufferList) Empty() bool {
+ return l.head == nil
+}
+
+// Front returns the first element of list l or nil.
+//
+//go:nosplit
+func (l *bufferList) Front() *buffer {
+ return l.head
+}
+
+// Back returns the last element of list l or nil.
+//
+//go:nosplit
+func (l *bufferList) Back() *buffer {
+ return l.tail
+}
+
+// Len returns the number of elements in the list.
+//
+// NOTE: This is an O(n) operation.
+//
+//go:nosplit
+func (l *bufferList) Len() (count int) {
+ for e := l.Front(); e != nil; e = (bufferElementMapper{}.linkerFor(e)).Next() {
+ count++
+ }
+ return count
+}
+
+// PushFront inserts the element e at the front of list l.
+//
+//go:nosplit
+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.
+//
+//go:nosplit
+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.
+//
+//go:nosplit
+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.
+//
+//go:nosplit
+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.
+//
+//go:nosplit
+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.
+//
+//go:nosplit
+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 if l.head == e {
+ l.head = next
+ }
+
+ if next != nil {
+ bufferElementMapper{}.linkerFor(next).SetPrev(prev)
+ } else if l.tail == e {
+ 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.
+//
+//go:nosplit
+func (e *bufferEntry) Next() *buffer {
+ return e.next
+}
+
+// Prev returns the entry that precedes e in the list.
+//
+//go:nosplit
+func (e *bufferEntry) Prev() *buffer {
+ return e.prev
+}
+
+// SetNext assigns 'entry' as the entry that follows e in the list.
+//
+//go:nosplit
+func (e *bufferEntry) SetNext(elem *buffer) {
+ e.next = elem
+}
+
+// SetPrev assigns 'entry' as the entry that precedes e in the list.
+//
+//go:nosplit
+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 100644
index 000000000..29007f642
--- /dev/null
+++ b/pkg/buffer/buffer_state_autogen.go
@@ -0,0 +1,153 @@
+// automatically generated by stateify.
+
+package buffer
+
+import (
+ "gvisor.dev/gvisor/pkg/state"
+)
+
+func (b *buffer) StateTypeName() string {
+ return "pkg/buffer.buffer"
+}
+
+func (b *buffer) StateFields() []string {
+ return []string{
+ "data",
+ "read",
+ "write",
+ "bufferEntry",
+ }
+}
+
+func (b *buffer) beforeSave() {}
+
+func (b *buffer) StateSave(stateSinkObject state.Sink) {
+ b.beforeSave()
+ stateSinkObject.Save(0, &b.data)
+ stateSinkObject.Save(1, &b.read)
+ stateSinkObject.Save(2, &b.write)
+ stateSinkObject.Save(3, &b.bufferEntry)
+}
+
+func (b *buffer) afterLoad() {}
+
+func (b *buffer) StateLoad(stateSourceObject state.Source) {
+ stateSourceObject.Load(0, &b.data)
+ stateSourceObject.Load(1, &b.read)
+ stateSourceObject.Load(2, &b.write)
+ stateSourceObject.Load(3, &b.bufferEntry)
+}
+
+func (l *bufferList) StateTypeName() string {
+ return "pkg/buffer.bufferList"
+}
+
+func (l *bufferList) StateFields() []string {
+ return []string{
+ "head",
+ "tail",
+ }
+}
+
+func (l *bufferList) beforeSave() {}
+
+func (l *bufferList) StateSave(stateSinkObject state.Sink) {
+ l.beforeSave()
+ stateSinkObject.Save(0, &l.head)
+ stateSinkObject.Save(1, &l.tail)
+}
+
+func (l *bufferList) afterLoad() {}
+
+func (l *bufferList) StateLoad(stateSourceObject state.Source) {
+ stateSourceObject.Load(0, &l.head)
+ stateSourceObject.Load(1, &l.tail)
+}
+
+func (e *bufferEntry) StateTypeName() string {
+ return "pkg/buffer.bufferEntry"
+}
+
+func (e *bufferEntry) StateFields() []string {
+ return []string{
+ "next",
+ "prev",
+ }
+}
+
+func (e *bufferEntry) beforeSave() {}
+
+func (e *bufferEntry) StateSave(stateSinkObject state.Sink) {
+ e.beforeSave()
+ stateSinkObject.Save(0, &e.next)
+ stateSinkObject.Save(1, &e.prev)
+}
+
+func (e *bufferEntry) afterLoad() {}
+
+func (e *bufferEntry) StateLoad(stateSourceObject state.Source) {
+ stateSourceObject.Load(0, &e.next)
+ stateSourceObject.Load(1, &e.prev)
+}
+
+func (p *pool) StateTypeName() string {
+ return "pkg/buffer.pool"
+}
+
+func (p *pool) StateFields() []string {
+ return []string{
+ "bufferSize",
+ "embeddedStorage",
+ }
+}
+
+func (p *pool) beforeSave() {}
+
+func (p *pool) StateSave(stateSinkObject state.Sink) {
+ p.beforeSave()
+ stateSinkObject.Save(0, &p.bufferSize)
+ stateSinkObject.Save(1, &p.embeddedStorage)
+}
+
+func (p *pool) StateLoad(stateSourceObject state.Source) {
+ stateSourceObject.Load(0, &p.bufferSize)
+ stateSourceObject.LoadWait(1, &p.embeddedStorage)
+ stateSourceObject.AfterLoad(p.afterLoad)
+}
+
+func (v *View) StateTypeName() string {
+ return "pkg/buffer.View"
+}
+
+func (v *View) StateFields() []string {
+ return []string{
+ "data",
+ "size",
+ "pool",
+ }
+}
+
+func (v *View) beforeSave() {}
+
+func (v *View) StateSave(stateSinkObject state.Sink) {
+ v.beforeSave()
+ stateSinkObject.Save(0, &v.data)
+ stateSinkObject.Save(1, &v.size)
+ stateSinkObject.Save(2, &v.pool)
+}
+
+func (v *View) afterLoad() {}
+
+func (v *View) StateLoad(stateSourceObject state.Source) {
+ stateSourceObject.Load(0, &v.data)
+ stateSourceObject.Load(1, &v.size)
+ stateSourceObject.Load(2, &v.pool)
+}
+
+func init() {
+ state.Register((*buffer)(nil))
+ state.Register((*bufferList)(nil))
+ state.Register((*bufferEntry)(nil))
+ state.Register((*pool)(nil))
+ state.Register((*View)(nil))
+}
diff --git a/pkg/buffer/buffer_unsafe_state_autogen.go b/pkg/buffer/buffer_unsafe_state_autogen.go
new file mode 100644
index 000000000..5a5c40722
--- /dev/null
+++ b/pkg/buffer/buffer_unsafe_state_autogen.go
@@ -0,0 +1,3 @@
+// automatically generated by stateify.
+
+package buffer
diff --git a/pkg/buffer/pool_test.go b/pkg/buffer/pool_test.go
deleted file mode 100644
index 8584bac89..000000000
--- a/pkg/buffer/pool_test.go
+++ /dev/null
@@ -1,51 +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 (
- "testing"
-)
-
-func TestGetDefaultBufferSize(t *testing.T) {
- var p pool
- for i := 0; i < embeddedCount*2; i++ {
- buf := p.get()
- if got, want := len(buf.data), defaultBufferSize; got != want {
- t.Errorf("#%d len(buf.data) = %d, want %d", i, got, want)
- }
- }
-}
-
-func TestGetCustomBufferSize(t *testing.T) {
- const size = 100
-
- var p pool
- p.setBufferSize(size)
- for i := 0; i < embeddedCount*2; i++ {
- buf := p.get()
- if got, want := len(buf.data), size; got != want {
- t.Errorf("#%d len(buf.data) = %d, want %d", i, got, want)
- }
- }
-}
-
-func TestPut(t *testing.T) {
- var p pool
- buf := p.get()
- p.put(buf)
- if buf.data != nil {
- t.Errorf("buf.data = %x, want nil", buf.data)
- }
-}
diff --git a/pkg/buffer/safemem_test.go b/pkg/buffer/safemem_test.go
deleted file mode 100644
index 721cc5934..000000000
--- a/pkg/buffer/safemem_test.go
+++ /dev/null
@@ -1,172 +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"
-
- "gvisor.dev/gvisor/pkg/safemem"
-)
-
-func TestSafemem(t *testing.T) {
- const bufferSize = defaultBufferSize
-
- testCases := []struct {
- name string
- input string
- output string
- readLen int
- op func(*View)
- }{
- // Basic coverage.
- {
- name: "short",
- input: "010",
- output: "010",
- },
- {
- name: "long",
- input: "0" + strings.Repeat("1", bufferSize) + "0",
- output: "0" + strings.Repeat("1", bufferSize) + "0",
- },
- {
- name: "short-read",
- input: "0",
- readLen: 100, // > size.
- output: "0",
- },
- {
- name: "zero-read",
- input: "0",
- output: "",
- },
- {
- name: "read-empty",
- input: "",
- readLen: 1, // > size.
- output: "",
- },
-
- // Ensure offsets work.
- {
- name: "offsets-short",
- input: "012",
- output: "2",
- op: func(v *View) {
- v.TrimFront(2)
- },
- },
- {
- name: "offsets-long0",
- input: "0" + strings.Repeat("1", bufferSize) + "0",
- output: strings.Repeat("1", bufferSize) + "0",
- op: func(v *View) {
- v.TrimFront(1)
- },
- },
- {
- name: "offsets-long1",
- input: "0" + strings.Repeat("1", bufferSize) + "0",
- output: strings.Repeat("1", bufferSize-1) + "0",
- op: func(v *View) {
- v.TrimFront(2)
- },
- },
- {
- name: "offsets-long2",
- input: "0" + strings.Repeat("1", bufferSize) + "0",
- output: "10",
- op: func(v *View) {
- v.TrimFront(bufferSize)
- },
- },
-
- // Ensure truncation works.
- {
- name: "truncate-short",
- input: "012",
- output: "01",
- op: func(v *View) {
- v.Truncate(2)
- },
- },
- {
- name: "truncate-long0",
- input: "0" + strings.Repeat("1", bufferSize) + "0",
- output: "0" + strings.Repeat("1", bufferSize),
- op: func(v *View) {
- v.Truncate(bufferSize + 1)
- },
- },
- {
- name: "truncate-long1",
- input: "0" + strings.Repeat("1", bufferSize) + "0",
- output: "0" + strings.Repeat("1", bufferSize-1),
- op: func(v *View) {
- v.Truncate(bufferSize)
- },
- },
- {
- name: "truncate-long2",
- input: "0" + strings.Repeat("1", bufferSize) + "0",
- output: "01",
- op: func(v *View) {
- v.Truncate(2)
- },
- },
- }
-
- for _, tc := range testCases {
- t.Run(tc.name, func(t *testing.T) {
- // Construct the new view.
- var view View
- bs := safemem.BlockSeqOf(safemem.BlockFromSafeSlice([]byte(tc.input)))
- n, err := view.WriteFromBlocks(bs)
- if err != nil {
- t.Errorf("expected err nil, got %v", err)
- }
- if n != uint64(len(tc.input)) {
- t.Errorf("expected %d bytes, got %d", len(tc.input), n)
- }
-
- // Run the operation.
- if tc.op != nil {
- tc.op(&view)
- }
-
- // Read and validate.
- readLen := tc.readLen
- if readLen == 0 {
- readLen = len(tc.output) // Default.
- }
- out := make([]byte, readLen)
- bs = safemem.BlockSeqOf(safemem.BlockFromSafeSlice(out))
- n, err = view.ReadToBlocks(bs)
- if err != nil {
- t.Errorf("expected nil, got %v", err)
- }
- if n != uint64(len(tc.output)) {
- t.Errorf("expected %d bytes, got %d", len(tc.output), n)
- }
-
- // Ensure the contents are correct.
- if !bytes.Equal(out[:n], []byte(tc.output[:n])) {
- t.Errorf("contents are wrong: expected %q, got %q", tc.output, string(out))
- }
- })
- }
-}
diff --git a/pkg/buffer/view_test.go b/pkg/buffer/view_test.go
deleted file mode 100644
index 839af0223..000000000
--- a/pkg/buffer/view_test.go
+++ /dev/null
@@ -1,544 +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"
- "context"
- "io"
- "strings"
- "testing"
-
- "gvisor.dev/gvisor/pkg/state"
-)
-
-const bufferSize = defaultBufferSize
-
-func fillAppend(v *View, data []byte) {
- v.Append(data)
-}
-
-func fillAppendEnd(v *View, data []byte) {
- v.Grow(bufferSize-1, false)
- v.Append(data)
- v.TrimFront(bufferSize - 1)
-}
-
-func fillWriteFromReader(v *View, data []byte) {
- b := bytes.NewBuffer(data)
- v.WriteFromReader(b, int64(len(data)))
-}
-
-func fillWriteFromReaderEnd(v *View, data []byte) {
- v.Grow(bufferSize-1, false)
- b := bytes.NewBuffer(data)
- v.WriteFromReader(b, int64(len(data)))
- v.TrimFront(bufferSize - 1)
-}
-
-var fillFuncs = map[string]func(*View, []byte){
- "append": fillAppend,
- "appendEnd": fillAppendEnd,
- "writeFromReader": fillWriteFromReader,
- "writeFromReaderEnd": fillWriteFromReaderEnd,
-}
-
-func BenchmarkReadAt(b *testing.B) {
- b.ReportAllocs()
- var v View
- v.Append(make([]byte, 100))
-
- buf := make([]byte, 10)
- for i := 0; i < b.N; i++ {
- v.ReadAt(buf, 0)
- }
-}
-
-func BenchmarkWriteRead(b *testing.B) {
- b.ReportAllocs()
- var v View
- sz := 1000
- wbuf := make([]byte, sz)
- rbuf := bytes.NewBuffer(make([]byte, sz))
- for i := 0; i < b.N; i++ {
- v.Append(wbuf)
- rbuf.Reset()
- v.ReadToWriter(rbuf, int64(sz))
- }
-}
-
-func testReadAt(t *testing.T, v *View, offset int64, n int, wantStr string, wantErr error) {
- t.Helper()
- d := make([]byte, n)
- n, err := v.ReadAt(d, offset)
- if n != len(wantStr) {
- t.Errorf("got %d, want %d", n, len(wantStr))
- }
- if err != wantErr {
- t.Errorf("got err %v, want %v", err, wantErr)
- }
- if !bytes.Equal(d[:n], []byte(wantStr)) {
- t.Errorf("got %q, want %q", string(d[:n]), wantStr)
- }
-}
-
-func TestView(t *testing.T) {
- testCases := []struct {
- name string
- input string
- output string
- op func(*testing.T, *View)
- }{
- // Preconditions.
- {
- name: "truncate-check",
- input: "hello",
- output: "hello", // Not touched.
- op: func(t *testing.T, v *View) {
- defer func() {
- if r := recover(); r == nil {
- t.Errorf("Truncate(-1) did not panic")
- }
- }()
- v.Truncate(-1)
- },
- },
- {
- name: "grow-check",
- input: "hello",
- output: "hello", // Not touched.
- op: func(t *testing.T, v *View) {
- defer func() {
- if r := recover(); r == nil {
- t.Errorf("Grow(-1) did not panic")
- }
- }()
- v.Grow(-1, false)
- },
- },
- {
- name: "advance-check",
- input: "hello",
- output: "", // Consumed.
- op: func(t *testing.T, v *View) {
- defer func() {
- if r := recover(); r == nil {
- t.Errorf("advanceRead(Size()+1) did not panic")
- }
- }()
- v.advanceRead(v.Size() + 1)
- },
- },
-
- // Prepend.
- {
- name: "prepend",
- input: "world",
- output: "hello world",
- op: func(t *testing.T, v *View) {
- v.Prepend([]byte("hello "))
- },
- },
- {
- name: "prepend-backfill-full",
- input: "hello world",
- output: "jello world",
- op: func(t *testing.T, v *View) {
- v.TrimFront(1)
- v.Prepend([]byte("j"))
- },
- },
- {
- name: "prepend-backfill-under",
- input: "hello world",
- output: "hola world",
- op: func(t *testing.T, v *View) {
- v.TrimFront(5)
- v.Prepend([]byte("hola"))
- },
- },
- {
- name: "prepend-backfill-over",
- input: "hello world",
- output: "smello world",
- op: func(t *testing.T, v *View) {
- v.TrimFront(1)
- v.Prepend([]byte("sm"))
- },
- },
- {
- name: "prepend-fill",
- input: strings.Repeat("1", bufferSize-1),
- output: "0" + strings.Repeat("1", bufferSize-1),
- op: func(t *testing.T, v *View) {
- v.Prepend([]byte("0"))
- },
- },
- {
- name: "prepend-overflow",
- input: strings.Repeat("1", bufferSize),
- output: "0" + strings.Repeat("1", bufferSize),
- op: func(t *testing.T, v *View) {
- v.Prepend([]byte("0"))
- },
- },
- {
- name: "prepend-multiple-buffers",
- input: strings.Repeat("1", bufferSize-1),
- output: strings.Repeat("0", bufferSize*3) + strings.Repeat("1", bufferSize-1),
- op: func(t *testing.T, v *View) {
- v.Prepend([]byte(strings.Repeat("0", bufferSize*3)))
- },
- },
-
- // Append and write.
- {
- name: "append",
- input: "hello",
- output: "hello world",
- op: func(t *testing.T, v *View) {
- v.Append([]byte(" world"))
- },
- },
- {
- name: "append-fill",
- input: strings.Repeat("1", bufferSize-1),
- output: strings.Repeat("1", bufferSize-1) + "0",
- op: func(t *testing.T, v *View) {
- v.Append([]byte("0"))
- },
- },
- {
- name: "append-overflow",
- input: strings.Repeat("1", bufferSize),
- output: strings.Repeat("1", bufferSize) + "0",
- op: func(t *testing.T, v *View) {
- v.Append([]byte("0"))
- },
- },
- {
- name: "append-multiple-buffers",
- input: strings.Repeat("1", bufferSize-1),
- output: strings.Repeat("1", bufferSize-1) + strings.Repeat("0", bufferSize*3),
- op: func(t *testing.T, v *View) {
- v.Append([]byte(strings.Repeat("0", bufferSize*3)))
- },
- },
-
- // Truncate.
- {
- name: "truncate",
- input: "hello world",
- output: "hello",
- op: func(t *testing.T, v *View) {
- v.Truncate(5)
- },
- },
- {
- name: "truncate-noop",
- input: "hello world",
- output: "hello world",
- op: func(t *testing.T, v *View) {
- v.Truncate(v.Size() + 1)
- },
- },
- {
- name: "truncate-multiple-buffers",
- input: strings.Repeat("1", bufferSize*2),
- output: strings.Repeat("1", bufferSize*2-1),
- op: func(t *testing.T, v *View) {
- v.Truncate(bufferSize*2 - 1)
- },
- },
- {
- name: "truncate-multiple-buffers-to-one",
- input: strings.Repeat("1", bufferSize*2),
- output: "11111",
- op: func(t *testing.T, v *View) {
- v.Truncate(5)
- },
- },
-
- // TrimFront.
- {
- name: "trim",
- input: "hello world",
- output: "world",
- op: func(t *testing.T, v *View) {
- v.TrimFront(6)
- },
- },
- {
- name: "trim-too-large",
- input: "hello world",
- output: "",
- op: func(t *testing.T, v *View) {
- v.TrimFront(v.Size() + 1)
- },
- },
- {
- name: "trim-multiple-buffers",
- input: strings.Repeat("1", bufferSize*2),
- output: strings.Repeat("1", bufferSize*2-1),
- op: func(t *testing.T, v *View) {
- v.TrimFront(1)
- },
- },
- {
- name: "trim-multiple-buffers-to-one-buffer",
- input: strings.Repeat("1", bufferSize*2),
- output: "1",
- op: func(t *testing.T, v *View) {
- v.TrimFront(bufferSize*2 - 1)
- },
- },
-
- // Grow.
- {
- name: "grow",
- input: "hello world",
- output: "hello world",
- op: func(t *testing.T, v *View) {
- v.Grow(1, true)
- },
- },
- {
- name: "grow-from-zero",
- output: strings.Repeat("\x00", 1024),
- op: func(t *testing.T, v *View) {
- v.Grow(1024, true)
- },
- },
- {
- name: "grow-from-non-zero",
- input: strings.Repeat("1", bufferSize),
- output: strings.Repeat("1", bufferSize) + strings.Repeat("\x00", bufferSize),
- op: func(t *testing.T, v *View) {
- v.Grow(bufferSize*2, true)
- },
- },
-
- // Copy.
- {
- name: "copy",
- input: "hello",
- output: "hello",
- op: func(t *testing.T, v *View) {
- other := v.Copy()
- bs := other.Flatten()
- want := []byte("hello")
- if !bytes.Equal(bs, want) {
- t.Errorf("expected %v, got %v", want, bs)
- }
- },
- },
- {
- name: "copy-large",
- input: strings.Repeat("1", bufferSize+1),
- output: strings.Repeat("1", bufferSize+1),
- op: func(t *testing.T, v *View) {
- other := v.Copy()
- bs := other.Flatten()
- want := []byte(strings.Repeat("1", bufferSize+1))
- if !bytes.Equal(bs, want) {
- t.Errorf("expected %v, got %v", want, bs)
- }
- },
- },
-
- // Merge.
- {
- name: "merge",
- input: "hello",
- output: "hello world",
- op: func(t *testing.T, v *View) {
- var other View
- other.Append([]byte(" world"))
- v.Merge(&other)
- if sz := other.Size(); sz != 0 {
- t.Errorf("expected 0, got %d", sz)
- }
- },
- },
- {
- name: "merge-large",
- input: strings.Repeat("1", bufferSize+1),
- output: strings.Repeat("1", bufferSize+1) + strings.Repeat("0", bufferSize+1),
- op: func(t *testing.T, v *View) {
- var other View
- other.Append([]byte(strings.Repeat("0", bufferSize+1)))
- v.Merge(&other)
- if sz := other.Size(); sz != 0 {
- t.Errorf("expected 0, got %d", sz)
- }
- },
- },
-
- // ReadAt.
- {
- name: "readat",
- input: "hello",
- output: "hello",
- op: func(t *testing.T, v *View) { testReadAt(t, v, 0, 6, "hello", io.EOF) },
- },
- {
- name: "readat-long",
- input: "hello",
- output: "hello",
- op: func(t *testing.T, v *View) { testReadAt(t, v, 0, 8, "hello", io.EOF) },
- },
- {
- name: "readat-short",
- input: "hello",
- output: "hello",
- op: func(t *testing.T, v *View) { testReadAt(t, v, 0, 3, "hel", nil) },
- },
- {
- name: "readat-offset",
- input: "hello",
- output: "hello",
- op: func(t *testing.T, v *View) { testReadAt(t, v, 2, 3, "llo", io.EOF) },
- },
- {
- name: "readat-long-offset",
- input: "hello",
- output: "hello",
- op: func(t *testing.T, v *View) { testReadAt(t, v, 2, 8, "llo", io.EOF) },
- },
- {
- name: "readat-short-offset",
- input: "hello",
- output: "hello",
- op: func(t *testing.T, v *View) { testReadAt(t, v, 2, 2, "ll", nil) },
- },
- {
- name: "readat-skip-all",
- input: "hello",
- output: "hello",
- op: func(t *testing.T, v *View) { testReadAt(t, v, bufferSize+1, 1, "", io.EOF) },
- },
- {
- name: "readat-second-buffer",
- input: strings.Repeat("0", bufferSize+1) + "12",
- output: strings.Repeat("0", bufferSize+1) + "12",
- op: func(t *testing.T, v *View) { testReadAt(t, v, bufferSize+1, 1, "1", nil) },
- },
- {
- name: "readat-second-buffer-end",
- input: strings.Repeat("0", bufferSize+1) + "12",
- output: strings.Repeat("0", bufferSize+1) + "12",
- op: func(t *testing.T, v *View) { testReadAt(t, v, bufferSize+1, 2, "12", io.EOF) },
- },
- }
-
- for _, tc := range testCases {
- for fillName, fn := range fillFuncs {
- t.Run(fillName+"/"+tc.name, func(t *testing.T) {
- // Construct & fill the view.
- var view View
- fn(&view, []byte(tc.input))
-
- // Run the operation.
- if tc.op != nil {
- tc.op(t, &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())
- }
-
- // Calculate contents via apply.
- var appliedOut []byte
- view.Apply(func(b []byte) {
- appliedOut = append(appliedOut, b...)
- })
- if len(appliedOut) != len(out) {
- t.Errorf("expected %d, got %d", len(out), len(appliedOut))
- }
- if !bytes.Equal(appliedOut, out) {
- t.Errorf("expected %v, got %v", out, appliedOut)
- }
-
- // Calculate contents via ReadToWriter.
- var b bytes.Buffer
- n, err := view.ReadToWriter(&b, int64(len(out)))
- if n != int64(len(out)) {
- t.Errorf("expected %d, got %d", len(out), n)
- }
- if err != nil {
- t.Errorf("expected nil, got %v", err)
- }
- if !bytes.Equal(b.Bytes(), out) {
- t.Errorf("expected %v, got %v", out, b.Bytes())
- }
- })
- }
- }
-}
-
-func doSaveAndLoad(t *testing.T, toSave, toLoad *View) {
- t.Helper()
- var buf bytes.Buffer
- ctx := context.Background()
- if _, err := state.Save(ctx, &buf, toSave); err != nil {
- t.Fatal("state.Save:", err)
- }
- if _, err := state.Load(ctx, bytes.NewReader(buf.Bytes()), toLoad); err != nil {
- t.Fatal("state.Load:", err)
- }
-}
-
-func TestSaveRestoreViewEmpty(t *testing.T) {
- var toSave View
- var v View
- doSaveAndLoad(t, &toSave, &v)
-
- if got := v.pool.avail; got != nil {
- t.Errorf("pool is not in zero state: v.pool.avail = %v, want nil", got)
- }
- if got := v.Flatten(); len(got) != 0 {
- t.Errorf("v.Flatten() = %x, want []", got)
- }
-}
-
-func TestSaveRestoreView(t *testing.T) {
- // Create data that fits 2.5 slots.
- data := bytes.Join([][]byte{
- bytes.Repeat([]byte{1, 2}, defaultBufferSize),
- bytes.Repeat([]byte{3}, defaultBufferSize/2),
- }, nil)
-
- var toSave View
- toSave.Append(data)
-
- var v View
- doSaveAndLoad(t, &toSave, &v)
-
- // Next available slot at index 3; 0-2 slot are used.
- i := 3
- if got, want := &v.pool.avail[0], &v.pool.embeddedStorage[i]; got != want {
- t.Errorf("next available buffer points to %p, want %p (&v.pool.embeddedStorage[%d])", got, want, i)
- }
- if got := v.Flatten(); !bytes.Equal(got, data) {
- t.Errorf("v.Flatten() = %x, want %x", got, data)
- }
-}