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Diffstat (limited to 'doc/talks/io2010')
-rw-r--r--doc/talks/io2010/balance.go168
-rw-r--r--doc/talks/io2010/decrypt.go85
-rw-r--r--doc/talks/io2010/encrypt.go52
-rw-r--r--doc/talks/io2010/eval1.go227
-rw-r--r--doc/talks/io2010/eval2.go259
-rw-r--r--doc/talks/io2010/talk.pdfbin1094941 -> 0 bytes
6 files changed, 0 insertions, 791 deletions
diff --git a/doc/talks/io2010/balance.go b/doc/talks/io2010/balance.go
deleted file mode 100644
index a3825cbc5..000000000
--- a/doc/talks/io2010/balance.go
+++ /dev/null
@@ -1,168 +0,0 @@
-// Copyright 2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package main
-
-import (
- "container/heap"
- "flag"
- "fmt"
- "math/rand"
- "time"
-)
-
-const nRequester = 100
-const nWorker = 10
-
-var roundRobin = flag.Bool("r", false, "use round-robin scheduling")
-
-// Simulation of some work: just sleep for a while and report how long.
-func op() int {
- n := rand.Int63n(1e9)
- time.Sleep(nWorker * n)
- return int(n)
-}
-
-type Request struct {
- fn func() int
- c chan int
-}
-
-func requester(work chan Request) {
- c := make(chan int)
- for {
- time.Sleep(rand.Int63n(nWorker * 2e9))
- work <- Request{op, c}
- <-c
- }
-}
-
-type Worker struct {
- i int
- requests chan Request
- pending int
-}
-
-func (w *Worker) work(done chan *Worker) {
- for {
- req := <-w.requests
- req.c <- req.fn()
- done <- w
- }
-}
-
-type Pool []*Worker
-
-func (p Pool) Len() int { return len(p) }
-
-func (p Pool) Less(i, j int) bool {
- return p[i].pending < p[j].pending
-}
-
-func (p *Pool) Swap(i, j int) {
- a := *p
- a[i], a[j] = a[j], a[i]
- a[i].i = i
- a[j].i = j
-}
-
-func (p *Pool) Push(x interface{}) {
- a := *p
- n := len(a)
- a = a[0 : n+1]
- w := x.(*Worker)
- a[n] = w
- w.i = n
- *p = a
-}
-
-func (p *Pool) Pop() interface{} {
- a := *p
- *p = a[0 : len(a)-1]
- w := a[len(a)-1]
- w.i = -1 // for safety
- return w
-}
-
-type Balancer struct {
- pool Pool
- done chan *Worker
- i int
-}
-
-func NewBalancer() *Balancer {
- done := make(chan *Worker, nWorker)
- b := &Balancer{make(Pool, 0, nWorker), done, 0}
- for i := 0; i < nWorker; i++ {
- w := &Worker{requests: make(chan Request, nRequester)}
- heap.Push(&b.pool, w)
- go w.work(b.done)
- }
- return b
-}
-
-func (b *Balancer) balance(work chan Request) {
- for {
- select {
- case req := <-work:
- b.dispatch(req)
- case w := <-b.done:
- b.completed(w)
- }
- b.print()
- }
-}
-
-func (b *Balancer) print() {
- sum := 0
- sumsq := 0
- for _, w := range b.pool {
- fmt.Printf("%d ", w.pending)
- sum += w.pending
- sumsq += w.pending * w.pending
- }
- avg := float64(sum) / float64(len(b.pool))
- variance := float64(sumsq)/float64(len(b.pool)) - avg*avg
- fmt.Printf(" %.2f %.2f\n", avg, variance)
-}
-
-func (b *Balancer) dispatch(req Request) {
- if *roundRobin {
- w := b.pool[b.i]
- w.requests <- req
- w.pending++
- b.i++
- if b.i >= len(b.pool) {
- b.i = 0
- }
- return
- }
-
- w := heap.Pop(&b.pool).(*Worker)
- w.requests <- req
- w.pending++
- // fmt.Printf("started %p; now %d\n", w, w.pending)
- heap.Push(&b.pool, w)
-}
-
-func (b *Balancer) completed(w *Worker) {
- if *roundRobin {
- w.pending--
- return
- }
-
- w.pending--
- // fmt.Printf("finished %p; now %d\n", w, w.pending)
- heap.Remove(&b.pool, w.i)
- heap.Push(&b.pool, w)
-}
-
-func main() {
- flag.Parse()
- work := make(chan Request)
- for i := 0; i < nRequester; i++ {
- go requester(work)
- }
- NewBalancer().balance(work)
-}
diff --git a/doc/talks/io2010/decrypt.go b/doc/talks/io2010/decrypt.go
deleted file mode 100644
index e63418b1a..000000000
--- a/doc/talks/io2010/decrypt.go
+++ /dev/null
@@ -1,85 +0,0 @@
-// Copyright 2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// This code differs from the slides in that it handles errors.
-
-package main
-
-import (
- "crypto/aes"
- "crypto/cipher"
- "compress/gzip"
- "io"
- "log"
- "os"
-)
-
-func EncryptAndGzip(dstfile, srcfile string, key, iv []byte) error {
- r, err := os.Open(srcfile)
- if err != nil {
- return err
- }
- var w io.Writer
- w, err = os.Create(dstfile)
- if err != nil {
- return err
- }
- c, err := aes.NewCipher(key)
- if err != nil {
- return err
- }
- w = cipher.StreamWriter{S: cipher.NewOFB(c, iv), W: w}
- w2, err := gzip.NewWriter(w)
- if err != nil {
- return err
- }
- defer w2.Close()
- _, err = io.Copy(w2, r)
- return err
-}
-
-func DecryptAndGunzip(dstfile, srcfile string, key, iv []byte) error {
- f, err := os.Open(srcfile)
- if err != nil {
- return err
- }
- defer f.Close()
- c, err := aes.NewCipher(key)
- if err != nil {
- return err
- }
- r := cipher.StreamReader{S: cipher.NewOFB(c, iv), R: f}
- r2, err := gzip.NewReader(r)
- if err != nil {
- return err
- }
- w, err := os.Create(dstfile)
- if err != nil {
- return err
- }
- defer w.Close()
- _, err = io.Copy(w, r2)
- return err
-}
-
-func main() {
- err := EncryptAndGzip(
- "/tmp/passwd.gz",
- "/etc/passwd",
- make([]byte, 16),
- make([]byte, 16),
- )
- if err != nil {
- log.Fatal(err)
- }
- err = DecryptAndGunzip(
- "/dev/stdout",
- "/tmp/passwd.gz",
- make([]byte, 16),
- make([]byte, 16),
- )
- if err != nil {
- log.Fatal(err)
- }
-}
diff --git a/doc/talks/io2010/encrypt.go b/doc/talks/io2010/encrypt.go
deleted file mode 100644
index 57c888c74..000000000
--- a/doc/talks/io2010/encrypt.go
+++ /dev/null
@@ -1,52 +0,0 @@
-// Copyright 2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// This code differs from the slides in that it handles errors.
-
-package main
-
-import (
- "crypto/aes"
- "crypto/cipher"
- "compress/gzip"
- "io"
- "log"
- "os"
-)
-
-func EncryptAndGzip(dstfile, srcfile string, key, iv []byte) error {
- r, err := os.Open(srcfile)
- if err != nil {
- return err
- }
- var w io.WriteCloser
- w, err = os.Create(dstfile)
- if err != nil {
- return err
- }
- defer w.Close()
- w, err = gzip.NewWriter(w)
- if err != nil {
- return err
- }
- defer w.Close()
- c, err := aes.NewCipher(key)
- if err != nil {
- return err
- }
- _, err = io.Copy(cipher.StreamWriter{S: cipher.NewOFB(c, iv), W: w}, r)
- return err
-}
-
-func main() {
- err := EncryptAndGzip(
- "/tmp/passwd.gz",
- "/etc/passwd",
- make([]byte, 16),
- make([]byte, 16),
- )
- if err != nil {
- log.Fatal(err)
- }
-}
diff --git a/doc/talks/io2010/eval1.go b/doc/talks/io2010/eval1.go
deleted file mode 100644
index 582f43e8e..000000000
--- a/doc/talks/io2010/eval1.go
+++ /dev/null
@@ -1,227 +0,0 @@
-// Copyright 2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package main
-
-import (
- "bufio"
- "fmt"
- "os"
- "strconv"
- "strings"
-)
-
-// Generic expression parser/evaluator
-
-type Value interface {
- String() string
- BinaryOp(op string, y Value) Value
-}
-
-type Parser struct {
- precTab map[string]int
- newVal func(string) Value
- src string
- pos int
- tok string
-}
-
-const alphanum = "_abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"
-
-func (p *Parser) stop(c uint8) bool {
- switch {
- case p.pos >= len(p.src):
- return true
- case c == '"':
- if p.src[p.pos] == '"' {
- p.pos++
- return true
- }
- return false
- case strings.IndexRune(alphanum, int(c)) >= 0:
- return strings.IndexRune(alphanum, int(p.src[p.pos])) < 0
- }
- return true
-}
-
-func (p *Parser) next() {
- // skip blanks
- for ; p.pos < len(p.src) && p.src[p.pos] <= ' '; p.pos++ {
- }
- if p.pos >= len(p.src) {
- p.tok = ""
- return
- }
- start := p.pos
- c := p.src[p.pos]
- for p.pos < len(p.src) {
- p.pos++
- if p.stop(c) {
- break
- }
- }
- p.tok = p.src[start:p.pos]
-}
-
-func (p *Parser) binaryExpr(prec1 int) Value {
- x := p.newVal(p.tok)
- p.next()
- for prec := p.precTab[p.tok]; prec >= prec1; prec-- {
- for p.precTab[p.tok] == prec {
- op := p.tok
- p.next()
- y := p.binaryExpr(prec + 1)
- x = x.BinaryOp(op, y)
- }
- }
- return x
-}
-
-func Eval(precTab map[string]int, newVal func(string) Value, src string) Value {
- var p Parser
- p.precTab = precTab
- p.newVal = newVal
- p.src = src
- p.next()
- return p.binaryExpr(1)
-}
-
-// Command-line expression evaluator
-
-func main() {
- r := bufio.NewReader(os.Stdin)
- for {
- fmt.Printf("> ")
- line, err := r.ReadString('\n')
- if err != nil {
- break
- }
- fmt.Printf("%s\n", Eval(precTab, trace(newVal), line))
- }
-}
-
-// Custom grammar and values
-
-var precTab = map[string]int{
- "&&": 1,
- "||": 2,
- "==": 3,
- "!=": 3,
- "<": 3,
- "<=": 3,
- ">": 3,
- ">=": 3,
- "+": 4,
- "-": 4,
- "*": 5,
- "/": 5,
- "%": 5,
-}
-
-func newVal(lit string) Value {
- x, err := strconv.Atoi(lit)
- if err == nil {
- return Int(x)
- }
- b, err := strconv.ParseBool(lit)
- if err == nil {
- return Bool(b)
- }
- return Error(fmt.Sprintf("illegal literal '%s'", lit))
-}
-
-type Error string
-
-func (e Error) String() string { return string(e) }
-func (e Error) BinaryOp(op string, y Value) Value { return e }
-
-type Int int
-
-func (x Int) String() string { return strconv.Itoa(int(x)) }
-func (x Int) BinaryOp(op string, y Value) Value {
- switch y := y.(type) {
- case Error:
- return y
- case Int:
- switch op {
- case "+":
- return x + y
- case "-":
- return x - y
- case "*":
- return x * y
- case "/":
- return x / y
- case "%":
- return x % y
- case "==":
- return Bool(x == y)
- case "!=":
- return Bool(x != y)
- case "<":
- return Bool(x < y)
- case "<=":
- return Bool(x <= y)
- case ">":
- return Bool(x > y)
- case ">=":
- return Bool(x >= y)
- }
- }
- return Error(fmt.Sprintf("illegal operation: '%v %s %v'", x, op, y))
-}
-
-type Bool bool
-
-func (x Bool) String() string { return strconv.FormatBool(bool(x)) }
-func (x Bool) BinaryOp(op string, y Value) Value {
- switch y := y.(type) {
- case Error:
- return y
- case Bool:
- switch op {
- case "&&":
- return Bool(x && y)
- case "||":
- return Bool(x || y)
- case "==":
- return Bool(x == y)
- case "!=":
- return Bool(x != y)
- }
- }
- return Error(fmt.Sprintf("illegal operation: '%v %s %v'", x, op, y))
-}
-
-func trace(newVal func(string) Value) func(string) Value {
- return func(s string) Value {
- v := newVal(s)
- fmt.Printf("\tnewVal(%q) = %s\n", s, fmtv(v))
- return &traceValue{v}
- }
-}
-
-type traceValue struct {
- Value
-}
-
-func (x *traceValue) BinaryOp(op string, y Value) Value {
- z := x.Value.BinaryOp(op, y.(*traceValue).Value)
- fmt.Printf("\t%s.BinaryOp(%q, %s) = %s\n", fmtv(x.Value), op, fmtv(y.(*traceValue).Value), fmtv(z))
- return &traceValue{z}
-}
-
-func (x *traceValue) String() string {
- s := x.Value.String()
- fmt.Printf("\t%s.String() = %#v\n", fmtv(x.Value), s)
- return s
-}
-
-func fmtv(v Value) string {
- t := fmt.Sprintf("%T", v)
- if i := strings.LastIndex(t, "."); i >= 0 { // strip package
- t = t[i+1:]
- }
- return fmt.Sprintf("%s(%#v)", t, v)
-}
diff --git a/doc/talks/io2010/eval2.go b/doc/talks/io2010/eval2.go
deleted file mode 100644
index 6f826e12d..000000000
--- a/doc/talks/io2010/eval2.go
+++ /dev/null
@@ -1,259 +0,0 @@
-// Copyright 2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package main
-
-import (
- "bufio"
- "fmt"
- "os"
- "strconv"
- "strings"
-)
-
-// Generic expression parser/evaluator
-
-type Value interface {
- String() string
- BinaryOp(op string, y Value) Value
-}
-
-type Parser struct {
- precTab map[string]int
- newVal func(string) Value
- src string
- pos int
- tok string
-}
-
-const alphanum = "_abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"
-
-func (p *Parser) stop(c uint8) bool {
- switch {
- case p.pos >= len(p.src):
- return true
- case c == '"':
- if p.src[p.pos] == '"' {
- p.pos++
- return true
- }
- return false
- case strings.IndexRune(alphanum, int(c)) >= 0:
- return strings.IndexRune(alphanum, int(p.src[p.pos])) < 0
- }
- return true
-}
-
-func (p *Parser) next() {
- // skip blanks
- for ; p.pos < len(p.src) && p.src[p.pos] <= ' '; p.pos++ {
- }
- if p.pos >= len(p.src) {
- p.tok = ""
- return
- }
- start := p.pos
- c := p.src[p.pos]
- for p.pos < len(p.src) {
- p.pos++
- if p.stop(c) {
- break
- }
- }
- p.tok = p.src[start:p.pos]
-}
-
-func (p *Parser) binaryExpr(prec1 int) Value {
- x := p.newVal(p.tok)
- p.next()
- for prec := p.precTab[p.tok]; prec >= prec1; prec-- {
- for p.precTab[p.tok] == prec {
- op := p.tok
- p.next()
- y := p.binaryExpr(prec + 1)
- x = x.BinaryOp(op, y)
- }
- }
- return x
-}
-
-func Eval(precTab map[string]int, newVal func(string) Value, src string) Value {
- var p Parser
- p.precTab = precTab
- p.newVal = newVal
- p.src = src
- p.next()
- return p.binaryExpr(1)
-}
-
-// Command-line expression evaluator
-
-func main() {
- r := bufio.NewReader(os.Stdin)
- for {
- fmt.Printf("> ")
- line, err := r.ReadString('\n')
- if err != nil {
- break
- }
- fmt.Printf("%s\n", Eval(precTab, trace(newVal), line))
- }
-}
-
-// Custom grammar and values
-
-var precTab = map[string]int{
- "&&": 1,
- "||": 2,
- "==": 3,
- "!=": 3,
- "<": 3,
- "<=": 3,
- ">": 3,
- ">=": 3,
- "+": 4,
- "-": 4,
- "*": 5,
- "/": 5,
- "%": 5,
-}
-
-func newVal(lit string) Value {
- x, err := strconv.Atoi(lit)
- if err == nil {
- return Int(x)
- }
- b, err := strconv.ParseBool(lit)
- if err == nil {
- return Bool(b)
- }
- s, err := strconv.Unquote(lit)
- if err == nil {
- return String(s)
- }
- return Error(fmt.Sprintf("illegal literal '%s'", lit))
-}
-
-type Error string
-
-func (e Error) String() string { return string(e) }
-func (e Error) BinaryOp(op string, y Value) Value { return e }
-
-type Int int
-
-func (x Int) String() string { return strconv.Itoa(int(x)) }
-func (x Int) BinaryOp(op string, y Value) Value {
- switch y := y.(type) {
- case Error:
- return y
- case String:
- switch op {
- case "*":
- return String(strings.Repeat(string(y), int(x)))
- }
- case Int:
- switch op {
- case "+":
- return x + y
- case "-":
- return x - y
- case "*":
- return x * y
- case "/":
- return x / y
- case "%":
- return x % y
- case "==":
- return Bool(x == y)
- case "!=":
- return Bool(x != y)
- case "<":
- return Bool(x < y)
- case "<=":
- return Bool(x <= y)
- case ">":
- return Bool(x > y)
- case ">=":
- return Bool(x >= y)
- }
- }
- return Error(fmt.Sprintf("illegal operation: '%v %s %v'", x, op, y))
-}
-
-type Bool bool
-
-func (x Bool) String() string { return strconv.FormatBool(bool(x)) }
-func (x Bool) BinaryOp(op string, y Value) Value {
- switch y := y.(type) {
- case Error:
- return y
- case Bool:
- switch op {
- case "&&":
- return Bool(x && y)
- case "||":
- return Bool(x || y)
- case "==":
- return Bool(x == y)
- case "!=":
- return Bool(x != y)
- }
- }
- return Error(fmt.Sprintf("illegal operation: '%v %s %v'", x, op, y))
-}
-
-type String string
-
-func (x String) String() string { return strconv.Quote(string(x)) }
-func (x String) BinaryOp(op string, y Value) Value {
- switch y := y.(type) {
- case Error:
- return y
- case Int:
- switch op {
- case "*":
- return String(strings.Repeat(string(x), int(y)))
- }
- case String:
- switch op {
- case "+":
- return x + y
- case "<":
- return Bool(x < y)
- }
- }
- return Error(fmt.Sprintf("illegal operation: '%v %s %v'", x, op, y))
-}
-
-func trace(newVal func(string) Value) func(string) Value {
- return func(s string) Value {
- v := newVal(s)
- fmt.Printf("\tnewVal(%q) = %s\n", s, fmtv(v))
- return &traceValue{v}
- }
-}
-
-type traceValue struct {
- Value
-}
-
-func (x *traceValue) BinaryOp(op string, y Value) Value {
- z := x.Value.BinaryOp(op, y.(*traceValue).Value)
- fmt.Printf("\t%s.BinaryOp(%q, %s) = %s\n", fmtv(x.Value), op, fmtv(y.(*traceValue).Value), fmtv(z))
- return &traceValue{z}
-}
-
-func (x *traceValue) String() string {
- s := x.Value.String()
- fmt.Printf("\t%s.String() = %#v\n", fmtv(x.Value), s)
- return s
-}
-
-func fmtv(v Value) string {
- t := fmt.Sprintf("%T", v)
- if i := strings.LastIndex(t, "."); i >= 0 { // strip package
- t = t[i+1:]
- }
- return fmt.Sprintf("%s(%#v)", t, v)
-}
diff --git a/doc/talks/io2010/talk.pdf b/doc/talks/io2010/talk.pdf
deleted file mode 100644
index aff42c21d..000000000
--- a/doc/talks/io2010/talk.pdf
+++ /dev/null
Binary files differ
generated by cgit v1.2.3 (git 2.39.1) at 2025-05-01 00:06:14 +0000