diff options
Diffstat (limited to 'pkg/buffer')
-rw-r--r-- | pkg/buffer/BUILD | 43 | ||||
-rw-r--r-- | pkg/buffer/buffer_list.go | 193 | ||||
-rw-r--r-- | pkg/buffer/buffer_state_autogen.go | 124 | ||||
-rw-r--r-- | pkg/buffer/buffer_unsafe_state_autogen.go | 3 | ||||
-rw-r--r-- | pkg/buffer/safemem_test.go | 170 | ||||
-rw-r--r-- | pkg/buffer/view_test.go | 467 |
6 files changed, 320 insertions, 680 deletions
diff --git a/pkg/buffer/BUILD b/pkg/buffer/BUILD deleted file mode 100644 index dcd086298..000000000 --- a/pkg/buffer/BUILD +++ /dev/null @@ -1,43 +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 = [ - "safemem_test.go", - "view_test.go", - ], - library = ":buffer", - deps = ["//pkg/safemem"], -) diff --git a/pkg/buffer/buffer_list.go b/pkg/buffer/buffer_list.go new file mode 100644 index 000000000..891ea961a --- /dev/null +++ b/pkg/buffer/buffer_list.go @@ -0,0 +1,193 @@ +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 +} + +// Len returns the number of elements in the list. +// +// NOTE: This is an O(n) operation. +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. +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 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. +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 100644 index 000000000..33887cb66 --- /dev/null +++ b/pkg/buffer/buffer_state_autogen.go @@ -0,0 +1,124 @@ +// automatically generated by stateify. + +package buffer + +import ( + "gvisor.dev/gvisor/pkg/state" +) + +func (x *buffer) StateTypeName() string { + return "pkg/buffer.buffer" +} + +func (x *buffer) StateFields() []string { + return []string{ + "data", + "read", + "write", + "bufferEntry", + } +} + +func (x *buffer) beforeSave() {} + +func (x *buffer) StateSave(m state.Sink) { + x.beforeSave() + m.Save(0, &x.data) + m.Save(1, &x.read) + m.Save(2, &x.write) + m.Save(3, &x.bufferEntry) +} + +func (x *buffer) afterLoad() {} + +func (x *buffer) StateLoad(m state.Source) { + m.Load(0, &x.data) + m.Load(1, &x.read) + m.Load(2, &x.write) + m.Load(3, &x.bufferEntry) +} + +func (x *bufferList) StateTypeName() string { + return "pkg/buffer.bufferList" +} + +func (x *bufferList) StateFields() []string { + return []string{ + "head", + "tail", + } +} + +func (x *bufferList) beforeSave() {} + +func (x *bufferList) StateSave(m state.Sink) { + x.beforeSave() + m.Save(0, &x.head) + m.Save(1, &x.tail) +} + +func (x *bufferList) afterLoad() {} + +func (x *bufferList) StateLoad(m state.Source) { + m.Load(0, &x.head) + m.Load(1, &x.tail) +} + +func (x *bufferEntry) StateTypeName() string { + return "pkg/buffer.bufferEntry" +} + +func (x *bufferEntry) StateFields() []string { + return []string{ + "next", + "prev", + } +} + +func (x *bufferEntry) beforeSave() {} + +func (x *bufferEntry) StateSave(m state.Sink) { + x.beforeSave() + m.Save(0, &x.next) + m.Save(1, &x.prev) +} + +func (x *bufferEntry) afterLoad() {} + +func (x *bufferEntry) StateLoad(m state.Source) { + m.Load(0, &x.next) + m.Load(1, &x.prev) +} + +func (x *View) StateTypeName() string { + return "pkg/buffer.View" +} + +func (x *View) StateFields() []string { + return []string{ + "data", + "size", + } +} + +func (x *View) beforeSave() {} + +func (x *View) StateSave(m state.Sink) { + x.beforeSave() + m.Save(0, &x.data) + m.Save(1, &x.size) +} + +func (x *View) afterLoad() {} + +func (x *View) StateLoad(m state.Source) { + m.Load(0, &x.data) + m.Load(1, &x.size) +} + +func init() { + state.Register((*buffer)(nil)) + state.Register((*bufferList)(nil)) + state.Register((*bufferEntry)(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/safemem_test.go b/pkg/buffer/safemem_test.go deleted file mode 100644 index 47f357e0c..000000000 --- a/pkg/buffer/safemem_test.go +++ /dev/null @@ -1,170 +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) { - 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 3db1bc6ee..000000000 --- a/pkg/buffer/view_test.go +++ /dev/null @@ -1,467 +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" - "io" - "strings" - "testing" -) - -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 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()) - } - }) - } - } -} |