diff options
Diffstat (limited to '')
-rw-r--r-- | test/chan/doubleselect.go | 87 | ||||
-rw-r--r-- | test/chan/fifo.go | 56 | ||||
-rw-r--r-- | test/chan/goroutines.go | 41 | ||||
-rw-r--r-- | test/chan/nonblock.go | 282 | ||||
-rw-r--r-- | test/chan/perm.go | 70 | ||||
-rw-r--r-- | test/chan/powser1.go | 741 | ||||
-rw-r--r-- | test/chan/powser2.go | 755 | ||||
-rw-r--r-- | test/chan/select.go | 58 | ||||
-rw-r--r-- | test/chan/select2.go | 54 | ||||
-rw-r--r-- | test/chan/select3.go | 226 | ||||
-rw-r--r-- | test/chan/select4.go | 31 | ||||
-rw-r--r-- | test/chan/select5.go | 481 | ||||
-rw-r--r-- | test/chan/select6.go | 34 | ||||
-rw-r--r-- | test/chan/select7.go | 68 | ||||
-rw-r--r-- | test/chan/select8.go | 55 | ||||
-rw-r--r-- | test/chan/sendstmt.go | 37 | ||||
-rw-r--r-- | test/chan/sieve1.go | 56 | ||||
-rw-r--r-- | test/chan/sieve2.go | 188 | ||||
-rw-r--r-- | test/chan/zerosize.go | 16 | ||||
-rw-r--r-- | test/chancap.go | 71 | ||||
-rw-r--r-- | test/chanlinear.go | 94 |
21 files changed, 3501 insertions, 0 deletions
diff --git a/test/chan/doubleselect.go b/test/chan/doubleselect.go new file mode 100644 index 0000000..ff69dbe --- /dev/null +++ b/test/chan/doubleselect.go @@ -0,0 +1,87 @@ +// run + +// Copyright 2009 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. + +// Test the situation in which two cases of a select can +// both end up running. See http://codereview.appspot.com/180068. + +package main + +import ( + "flag" + "runtime" +) + +var iterations *int = flag.Int("n", 100000, "number of iterations") + +// sender sends a counter to one of four different channels. If two +// cases both end up running in the same iteration, the same value will be sent +// to two different channels. +func sender(n int, c1, c2, c3, c4 chan<- int) { + defer close(c1) + defer close(c2) + defer close(c3) + defer close(c4) + + for i := 0; i < n; i++ { + select { + case c1 <- i: + case c2 <- i: + case c3 <- i: + case c4 <- i: + } + } +} + +// mux receives the values from sender and forwards them onto another channel. +// It would be simpler to just have sender's four cases all be the same +// channel, but this doesn't actually trigger the bug. +func mux(out chan<- int, in <-chan int, done chan<- bool) { + for v := range in { + out <- v + } + done <- true +} + +// recver gets a steam of values from the four mux's and checks for duplicates. +func recver(in <-chan int) { + seen := make(map[int]bool) + + for v := range in { + if _, ok := seen[v]; ok { + println("got duplicate value: ", v) + panic("fail") + } + seen[v] = true + } +} + +func main() { + runtime.GOMAXPROCS(2) + + flag.Parse() + c1 := make(chan int) + c2 := make(chan int) + c3 := make(chan int) + c4 := make(chan int) + done := make(chan bool) + cmux := make(chan int) + go sender(*iterations, c1, c2, c3, c4) + go mux(cmux, c1, done) + go mux(cmux, c2, done) + go mux(cmux, c3, done) + go mux(cmux, c4, done) + go func() { + <-done + <-done + <-done + <-done + close(cmux) + }() + // We keep the recver because it might catch more bugs in the future. + // However, the result of the bug linked to at the top is that we'll + // end up panicking with: "throw: bad g->status in ready". + recver(cmux) +} diff --git a/test/chan/fifo.go b/test/chan/fifo.go new file mode 100644 index 0000000..0001bcf --- /dev/null +++ b/test/chan/fifo.go @@ -0,0 +1,56 @@ +// run + +// Copyright 2009 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. + +// Test that unbuffered channels act as pure fifos. + +package main + +import "os" + +const N = 10 + +func AsynchFifo() { + ch := make(chan int, N) + for i := 0; i < N; i++ { + ch <- i + } + for i := 0; i < N; i++ { + if <-ch != i { + print("bad receive\n") + os.Exit(1) + } + } +} + +func Chain(ch <-chan int, val int, in <-chan int, out chan<- int) { + <-in + if <-ch != val { + panic(val) + } + out <- 1 +} + +// thread together a daisy chain to read the elements in sequence +func SynchFifo() { + ch := make(chan int) + in := make(chan int) + start := in + for i := 0; i < N; i++ { + out := make(chan int) + go Chain(ch, i, in, out) + in = out + } + start <- 0 + for i := 0; i < N; i++ { + ch <- i + } + <-in +} + +func main() { + AsynchFifo() + SynchFifo() +} diff --git a/test/chan/goroutines.go b/test/chan/goroutines.go new file mode 100644 index 0000000..6ffae7d --- /dev/null +++ b/test/chan/goroutines.go @@ -0,0 +1,41 @@ +// run + +// Copyright 2009 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. + +// Torture test for goroutines. +// Make a lot of goroutines, threaded together, and tear them down cleanly. + +package main + +import ( + "os" + "strconv" +) + +func f(left, right chan int) { + left <- <-right +} + +func main() { + var n = 10000 + if len(os.Args) > 1 { + var err error + n, err = strconv.Atoi(os.Args[1]) + if err != nil { + print("bad arg\n") + os.Exit(1) + } + } + leftmost := make(chan int) + right := leftmost + left := leftmost + for i := 0; i < n; i++ { + right = make(chan int) + go f(left, right) + left = right + } + go func(c chan int) { c <- 1 }(right) + <-leftmost +} diff --git a/test/chan/nonblock.go b/test/chan/nonblock.go new file mode 100644 index 0000000..7e3c0c7 --- /dev/null +++ b/test/chan/nonblock.go @@ -0,0 +1,282 @@ +// run + +// Copyright 2009 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. + +// Test channel operations that test for blocking. +// Use several sizes and types of operands. + +package main + +import "runtime" +import "time" + +func i32receiver(c chan int32, strobe chan bool) { + if <-c != 123 { + panic("i32 value") + } + strobe <- true +} + +func i32sender(c chan int32, strobe chan bool) { + c <- 234 + strobe <- true +} + +func i64receiver(c chan int64, strobe chan bool) { + if <-c != 123456 { + panic("i64 value") + } + strobe <- true +} + +func i64sender(c chan int64, strobe chan bool) { + c <- 234567 + strobe <- true +} + +func breceiver(c chan bool, strobe chan bool) { + if !<-c { + panic("b value") + } + strobe <- true +} + +func bsender(c chan bool, strobe chan bool) { + c <- true + strobe <- true +} + +func sreceiver(c chan string, strobe chan bool) { + if <-c != "hello" { + panic("s value") + } + strobe <- true +} + +func ssender(c chan string, strobe chan bool) { + c <- "hello again" + strobe <- true +} + +var ticker = time.Tick(10 * 1000) // 10 us +func sleep() { + <-ticker + <-ticker + runtime.Gosched() + runtime.Gosched() + runtime.Gosched() +} + +const maxTries = 10000 // Up to 100ms per test. + +func main() { + var i32 int32 + var i64 int64 + var b bool + var s string + + var sync = make(chan bool) + + for buffer := 0; buffer < 2; buffer++ { + c32 := make(chan int32, buffer) + c64 := make(chan int64, buffer) + cb := make(chan bool, buffer) + cs := make(chan string, buffer) + + select { + case i32 = <-c32: + panic("blocked i32sender") + default: + } + + select { + case i64 = <-c64: + panic("blocked i64sender") + default: + } + + select { + case b = <-cb: + panic("blocked bsender") + default: + } + + select { + case s = <-cs: + panic("blocked ssender") + default: + } + + go i32receiver(c32, sync) + try := 0 + Send32: + for { + select { + case c32 <- 123: + break Send32 + default: + try++ + if try > maxTries { + println("i32receiver buffer=", buffer) + panic("fail") + } + sleep() + } + } + <-sync + + go i32sender(c32, sync) + if buffer > 0 { + <-sync + } + try = 0 + Recv32: + for { + select { + case i32 = <-c32: + break Recv32 + default: + try++ + if try > maxTries { + println("i32sender buffer=", buffer) + panic("fail") + } + sleep() + } + } + if i32 != 234 { + panic("i32sender value") + } + if buffer == 0 { + <-sync + } + + go i64receiver(c64, sync) + try = 0 + Send64: + for { + select { + case c64 <- 123456: + break Send64 + default: + try++ + if try > maxTries { + panic("i64receiver") + } + sleep() + } + } + <-sync + + go i64sender(c64, sync) + if buffer > 0 { + <-sync + } + try = 0 + Recv64: + for { + select { + case i64 = <-c64: + break Recv64 + default: + try++ + if try > maxTries { + panic("i64sender") + } + sleep() + } + } + if i64 != 234567 { + panic("i64sender value") + } + if buffer == 0 { + <-sync + } + + go breceiver(cb, sync) + try = 0 + SendBool: + for { + select { + case cb <- true: + break SendBool + default: + try++ + if try > maxTries { + panic("breceiver") + } + sleep() + } + } + <-sync + + go bsender(cb, sync) + if buffer > 0 { + <-sync + } + try = 0 + RecvBool: + for { + select { + case b = <-cb: + break RecvBool + default: + try++ + if try > maxTries { + panic("bsender") + } + sleep() + } + } + if !b { + panic("bsender value") + } + if buffer == 0 { + <-sync + } + + go sreceiver(cs, sync) + try = 0 + SendString: + for { + select { + case cs <- "hello": + break SendString + default: + try++ + if try > maxTries { + panic("sreceiver") + } + sleep() + } + } + <-sync + + go ssender(cs, sync) + if buffer > 0 { + <-sync + } + try = 0 + RecvString: + for { + select { + case s = <-cs: + break RecvString + default: + try++ + if try > maxTries { + panic("ssender") + } + sleep() + } + } + if s != "hello again" { + panic("ssender value") + } + if buffer == 0 { + <-sync + } + } +} diff --git a/test/chan/perm.go b/test/chan/perm.go new file mode 100644 index 0000000..4c94ab7 --- /dev/null +++ b/test/chan/perm.go @@ -0,0 +1,70 @@ +// errorcheck + +// Copyright 2009 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. + +// Test various correct and incorrect permutations of send-only, +// receive-only, and bidirectional channels. +// Does not compile. + +package main + +var ( + cr <-chan int + cs chan<- int + c chan int +) + +func main() { + cr = c // ok + cs = c // ok + c = cr // ERROR "illegal types|incompatible|cannot" + c = cs // ERROR "illegal types|incompatible|cannot" + cr = cs // ERROR "illegal types|incompatible|cannot" + cs = cr // ERROR "illegal types|incompatible|cannot" + + var n int + <-n // ERROR "receive from non-chan|expected channel" + n <- 2 // ERROR "send to non-chan|must be channel" + + c <- 0 // ok + <-c // ok + x, ok := <-c // ok + _, _ = x, ok + + cr <- 0 // ERROR "send" + <-cr // ok + x, ok = <-cr // ok + _, _ = x, ok + + cs <- 0 // ok + <-cs // ERROR "receive" + x, ok = <-cs // ERROR "receive" + _, _ = x, ok + + select { + case c <- 0: // ok + case x := <-c: // ok + _ = x + + case cr <- 0: // ERROR "send" + case x := <-cr: // ok + _ = x + + case cs <- 0: // ok + case x := <-cs: // ERROR "receive" + _ = x + } + + for _ = range cs { // ERROR "receive" + } + + for range cs { // ERROR "receive" + } + + close(c) + close(cs) + close(cr) // ERROR "receive" + close(n) // ERROR "invalid operation.*non-chan type|must be channel|not a channel" +} diff --git a/test/chan/powser1.go b/test/chan/powser1.go new file mode 100644 index 0000000..e999dde --- /dev/null +++ b/test/chan/powser1.go @@ -0,0 +1,741 @@ +// run + +// Copyright 2009 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. + +// Test concurrency primitives: power series. + +// Power series package +// A power series is a channel, along which flow rational +// coefficients. A denominator of zero signifies the end. +// Original code in Newsqueak by Doug McIlroy. +// See Squinting at Power Series by Doug McIlroy, +// https://swtch.com/~rsc/thread/squint.pdf + +package main + +import "os" + +type rat struct { + num, den int64 // numerator, denominator +} + +func (u rat) pr() { + if u.den == 1 { + print(u.num) + } else { + print(u.num, "/", u.den) + } + print(" ") +} + +func (u rat) eq(c rat) bool { + return u.num == c.num && u.den == c.den +} + +type dch struct { + req chan int + dat chan rat + nam int +} + +type dch2 [2]*dch + +var chnames string +var chnameserial int +var seqno int + +func mkdch() *dch { + c := chnameserial % len(chnames) + chnameserial++ + d := new(dch) + d.req = make(chan int) + d.dat = make(chan rat) + d.nam = c + return d +} + +func mkdch2() *dch2 { + d2 := new(dch2) + d2[0] = mkdch() + d2[1] = mkdch() + return d2 +} + +// split reads a single demand channel and replicates its +// output onto two, which may be read at different rates. +// A process is created at first demand for a rat and dies +// after the rat has been sent to both outputs. + +// When multiple generations of split exist, the newest +// will service requests on one channel, which is +// always renamed to be out[0]; the oldest will service +// requests on the other channel, out[1]. All generations but the +// newest hold queued data that has already been sent to +// out[0]. When data has finally been sent to out[1], +// a signal on the release-wait channel tells the next newer +// generation to begin servicing out[1]. + +func dosplit(in *dch, out *dch2, wait chan int) { + both := false // do not service both channels + + select { + case <-out[0].req: + + case <-wait: + both = true + select { + case <-out[0].req: + + case <-out[1].req: + out[0], out[1] = out[1], out[0] + } + } + + seqno++ + in.req <- seqno + release := make(chan int) + go dosplit(in, out, release) + dat := <-in.dat + out[0].dat <- dat + if !both { + <-wait + } + <-out[1].req + out[1].dat <- dat + release <- 0 +} + +func split(in *dch, out *dch2) { + release := make(chan int) + go dosplit(in, out, release) + release <- 0 +} + +func put(dat rat, out *dch) { + <-out.req + out.dat <- dat +} + +func get(in *dch) rat { + seqno++ + in.req <- seqno + return <-in.dat +} + +// Get one rat from each of n demand channels + +func getn(in []*dch) []rat { + n := len(in) + if n != 2 { + panic("bad n in getn") + } + req := new([2]chan int) + dat := new([2]chan rat) + out := make([]rat, 2) + var i int + var it rat + for i = 0; i < n; i++ { + req[i] = in[i].req + dat[i] = nil + } + for n = 2 * n; n > 0; n-- { + seqno++ + + select { + case req[0] <- seqno: + dat[0] = in[0].dat + req[0] = nil + case req[1] <- seqno: + dat[1] = in[1].dat + req[1] = nil + case it = <-dat[0]: + out[0] = it + dat[0] = nil + case it = <-dat[1]: + out[1] = it + dat[1] = nil + } + } + return out +} + +// Get one rat from each of 2 demand channels + +func get2(in0 *dch, in1 *dch) []rat { + return getn([]*dch{in0, in1}) +} + +func copy(in *dch, out *dch) { + for { + <-out.req + out.dat <- get(in) + } +} + +func repeat(dat rat, out *dch) { + for { + put(dat, out) + } +} + +type PS *dch // power series +type PS2 *[2]PS // pair of power series + +var Ones PS +var Twos PS + +func mkPS() *dch { + return mkdch() +} + +func mkPS2() *dch2 { + return mkdch2() +} + +// Conventions +// Upper-case for power series. +// Lower-case for rationals. +// Input variables: U,V,... +// Output variables: ...,Y,Z + +// Integer gcd; needed for rational arithmetic + +func gcd(u, v int64) int64 { + if u < 0 { + return gcd(-u, v) + } + if u == 0 { + return v + } + return gcd(v%u, u) +} + +// Make a rational from two ints and from one int + +func i2tor(u, v int64) rat { + g := gcd(u, v) + var r rat + if v > 0 { + r.num = u / g + r.den = v / g + } else { + r.num = -u / g + r.den = -v / g + } + return r +} + +func itor(u int64) rat { + return i2tor(u, 1) +} + +var zero rat +var one rat + +// End mark and end test + +var finis rat + +func end(u rat) int64 { + if u.den == 0 { + return 1 + } + return 0 +} + +// Operations on rationals + +func add(u, v rat) rat { + g := gcd(u.den, v.den) + return i2tor(u.num*(v.den/g)+v.num*(u.den/g), u.den*(v.den/g)) +} + +func mul(u, v rat) rat { + g1 := gcd(u.num, v.den) + g2 := gcd(u.den, v.num) + var r rat + r.num = (u.num / g1) * (v.num / g2) + r.den = (u.den / g2) * (v.den / g1) + return r +} + +func neg(u rat) rat { + return i2tor(-u.num, u.den) +} + +func sub(u, v rat) rat { + return add(u, neg(v)) +} + +func inv(u rat) rat { // invert a rat + if u.num == 0 { + panic("zero divide in inv") + } + return i2tor(u.den, u.num) +} + +// print eval in floating point of PS at x=c to n terms +func evaln(c rat, U PS, n int) { + xn := float64(1) + x := float64(c.num) / float64(c.den) + val := float64(0) + for i := 0; i < n; i++ { + u := get(U) + if end(u) != 0 { + break + } + val = val + x*float64(u.num)/float64(u.den) + xn = xn * x + } + print(val, "\n") +} + +// Print n terms of a power series +func printn(U PS, n int) { + done := false + for ; !done && n > 0; n-- { + u := get(U) + if end(u) != 0 { + done = true + } else { + u.pr() + } + } + print(("\n")) +} + +// Evaluate n terms of power series U at x=c +func eval(c rat, U PS, n int) rat { + if n == 0 { + return zero + } + y := get(U) + if end(y) != 0 { + return zero + } + return add(y, mul(c, eval(c, U, n-1))) +} + +// Power-series constructors return channels on which power +// series flow. They start an encapsulated generator that +// puts the terms of the series on the channel. + +// Make a pair of power series identical to a given power series + +func Split(U PS) *dch2 { + UU := mkdch2() + go split(U, UU) + return UU +} + +// Add two power series +func Add(U, V PS) PS { + Z := mkPS() + go func() { + var uv []rat + for { + <-Z.req + uv = get2(U, V) + switch end(uv[0]) + 2*end(uv[1]) { + case 0: + Z.dat <- add(uv[0], uv[1]) + case 1: + Z.dat <- uv[1] + copy(V, Z) + case 2: + Z.dat <- uv[0] + copy(U, Z) + case 3: + Z.dat <- finis + } + } + }() + return Z +} + +// Multiply a power series by a constant +func Cmul(c rat, U PS) PS { + Z := mkPS() + go func() { + done := false + for !done { + <-Z.req + u := get(U) + if end(u) != 0 { + done = true + } else { + Z.dat <- mul(c, u) + } + } + Z.dat <- finis + }() + return Z +} + +// Subtract + +func Sub(U, V PS) PS { + return Add(U, Cmul(neg(one), V)) +} + +// Multiply a power series by the monomial x^n + +func Monmul(U PS, n int) PS { + Z := mkPS() + go func() { + for ; n > 0; n-- { + put(zero, Z) + } + copy(U, Z) + }() + return Z +} + +// Multiply by x + +func Xmul(U PS) PS { + return Monmul(U, 1) +} + +func Rep(c rat) PS { + Z := mkPS() + go repeat(c, Z) + return Z +} + +// Monomial c*x^n + +func Mon(c rat, n int) PS { + Z := mkPS() + go func() { + if c.num != 0 { + for ; n > 0; n = n - 1 { + put(zero, Z) + } + put(c, Z) + } + put(finis, Z) + }() + return Z +} + +func Shift(c rat, U PS) PS { + Z := mkPS() + go func() { + put(c, Z) + copy(U, Z) + }() + return Z +} + +// simple pole at 1: 1/(1-x) = 1 1 1 1 1 ... + +// Convert array of coefficients, constant term first +// to a (finite) power series + +/* +func Poly(a []rat) PS { + Z:=mkPS() + begin func(a []rat, Z PS) { + j:=0 + done:=0 + for j=len(a); !done&&j>0; j=j-1) + if(a[j-1].num!=0) done=1 + i:=0 + for(; i<j; i=i+1) put(a[i],Z) + put(finis,Z) + }() + return Z +} +*/ + +// Multiply. The algorithm is +// let U = u + x*UU +// let V = v + x*VV +// then UV = u*v + x*(u*VV+v*UU) + x*x*UU*VV + +func Mul(U, V PS) PS { + Z := mkPS() + go func() { + <-Z.req + uv := get2(U, V) + if end(uv[0]) != 0 || end(uv[1]) != 0 { + Z.dat <- finis + } else { + Z.dat <- mul(uv[0], uv[1]) + UU := Split(U) + VV := Split(V) + W := Add(Cmul(uv[0], VV[0]), Cmul(uv[1], UU[0])) + <-Z.req + Z.dat <- get(W) + copy(Add(W, Mul(UU[1], VV[1])), Z) + } + }() + return Z +} + +// Differentiate + +func Diff(U PS) PS { + Z := mkPS() + go func() { + <-Z.req + u := get(U) + if end(u) == 0 { + done := false + for i := 1; !done; i++ { + u = get(U) + if end(u) != 0 { + done = true + } else { + Z.dat <- mul(itor(int64(i)), u) + <-Z.req + } + } + } + Z.dat <- finis + }() + return Z +} + +// Integrate, with const of integration +func Integ(c rat, U PS) PS { + Z := mkPS() + go func() { + put(c, Z) + done := false + for i := 1; !done; i++ { + <-Z.req + u := get(U) + if end(u) != 0 { + done = true + } + Z.dat <- mul(i2tor(1, int64(i)), u) + } + Z.dat <- finis + }() + return Z +} + +// Binomial theorem (1+x)^c + +func Binom(c rat) PS { + Z := mkPS() + go func() { + n := 1 + t := itor(1) + for c.num != 0 { + put(t, Z) + t = mul(mul(t, c), i2tor(1, int64(n))) + c = sub(c, one) + n++ + } + put(finis, Z) + }() + return Z +} + +// Reciprocal of a power series +// let U = u + x*UU +// let Z = z + x*ZZ +// (u+x*UU)*(z+x*ZZ) = 1 +// z = 1/u +// u*ZZ + z*UU +x*UU*ZZ = 0 +// ZZ = -UU*(z+x*ZZ)/u + +func Recip(U PS) PS { + Z := mkPS() + go func() { + ZZ := mkPS2() + <-Z.req + z := inv(get(U)) + Z.dat <- z + split(Mul(Cmul(neg(z), U), Shift(z, ZZ[0])), ZZ) + copy(ZZ[1], Z) + }() + return Z +} + +// Exponential of a power series with constant term 0 +// (nonzero constant term would make nonrational coefficients) +// bug: the constant term is simply ignored +// Z = exp(U) +// DZ = Z*DU +// integrate to get Z + +func Exp(U PS) PS { + ZZ := mkPS2() + split(Integ(one, Mul(ZZ[0], Diff(U))), ZZ) + return ZZ[1] +} + +// Substitute V for x in U, where the leading term of V is zero +// let U = u + x*UU +// let V = v + x*VV +// then S(U,V) = u + VV*S(V,UU) +// bug: a nonzero constant term is ignored + +func Subst(U, V PS) PS { + Z := mkPS() + go func() { + VV := Split(V) + <-Z.req + u := get(U) + Z.dat <- u + if end(u) == 0 { + if end(get(VV[0])) != 0 { + put(finis, Z) + } else { + copy(Mul(VV[0], Subst(U, VV[1])), Z) + } + } + }() + return Z +} + +// Monomial Substitution: U(c x^n) +// Each Ui is multiplied by c^i and followed by n-1 zeros + +func MonSubst(U PS, c0 rat, n int) PS { + Z := mkPS() + go func() { + c := one + for { + <-Z.req + u := get(U) + Z.dat <- mul(u, c) + c = mul(c, c0) + if end(u) != 0 { + Z.dat <- finis + break + } + for i := 1; i < n; i++ { + <-Z.req + Z.dat <- zero + } + } + }() + return Z +} + +func Init() { + chnameserial = -1 + seqno = 0 + chnames = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz" + zero = itor(0) + one = itor(1) + finis = i2tor(1, 0) + Ones = Rep(one) + Twos = Rep(itor(2)) +} + +func check(U PS, c rat, count int, str string) { + for i := 0; i < count; i++ { + r := get(U) + if !r.eq(c) { + print("got: ") + r.pr() + print("should get ") + c.pr() + print("\n") + panic(str) + } + } +} + +const N = 10 + +func checka(U PS, a []rat, str string) { + for i := 0; i < N; i++ { + check(U, a[i], 1, str) + } +} + +func main() { + Init() + if len(os.Args) > 1 { // print + print("Ones: ") + printn(Ones, 10) + print("Twos: ") + printn(Twos, 10) + print("Add: ") + printn(Add(Ones, Twos), 10) + print("Diff: ") + printn(Diff(Ones), 10) + print("Integ: ") + printn(Integ(zero, Ones), 10) + print("CMul: ") + printn(Cmul(neg(one), Ones), 10) + print("Sub: ") + printn(Sub(Ones, Twos), 10) + print("Mul: ") + printn(Mul(Ones, Ones), 10) + print("Exp: ") + printn(Exp(Ones), 15) + print("MonSubst: ") + printn(MonSubst(Ones, neg(one), 2), 10) + print("ATan: ") + printn(Integ(zero, MonSubst(Ones, neg(one), 2)), 10) + } else { // test + check(Ones, one, 5, "Ones") + check(Add(Ones, Ones), itor(2), 0, "Add Ones Ones") // 1 1 1 1 1 + check(Add(Ones, Twos), itor(3), 0, "Add Ones Twos") // 3 3 3 3 3 + a := make([]rat, N) + d := Diff(Ones) + for i := 0; i < N; i++ { + a[i] = itor(int64(i + 1)) + } + checka(d, a, "Diff") // 1 2 3 4 5 + in := Integ(zero, Ones) + a[0] = zero // integration constant + for i := 1; i < N; i++ { + a[i] = i2tor(1, int64(i)) + } + checka(in, a, "Integ") // 0 1 1/2 1/3 1/4 1/5 + check(Cmul(neg(one), Twos), itor(-2), 10, "CMul") // -1 -1 -1 -1 -1 + check(Sub(Ones, Twos), itor(-1), 0, "Sub Ones Twos") // -1 -1 -1 -1 -1 + m := Mul(Ones, Ones) + for i := 0; i < N; i++ { + a[i] = itor(int64(i + 1)) + } + checka(m, a, "Mul") // 1 2 3 4 5 + e := Exp(Ones) + a[0] = itor(1) + a[1] = itor(1) + a[2] = i2tor(3, 2) + a[3] = i2tor(13, 6) + a[4] = i2tor(73, 24) + a[5] = i2tor(167, 40) + a[6] = i2tor(4051, 720) + a[7] = i2tor(37633, 5040) + a[8] = i2tor(43817, 4480) + a[9] = i2tor(4596553, 362880) + checka(e, a, "Exp") // 1 1 3/2 13/6 73/24 + at := Integ(zero, MonSubst(Ones, neg(one), 2)) + for c, i := 1, 0; i < N; i++ { + if i%2 == 0 { + a[i] = zero + } else { + a[i] = i2tor(int64(c), int64(i)) + c *= -1 + } + } + checka(at, a, "ATan") // 0 -1 0 -1/3 0 -1/5 + /* + t := Revert(Integ(zero, MonSubst(Ones, neg(one), 2))) + a[0] = zero + a[1] = itor(1) + a[2] = zero + a[3] = i2tor(1,3) + a[4] = zero + a[5] = i2tor(2,15) + a[6] = zero + a[7] = i2tor(17,315) + a[8] = zero + a[9] = i2tor(62,2835) + checka(t, a, "Tan") // 0 1 0 1/3 0 2/15 + */ + } +} diff --git a/test/chan/powser2.go b/test/chan/powser2.go new file mode 100644 index 0000000..72cbba8 --- /dev/null +++ b/test/chan/powser2.go @@ -0,0 +1,755 @@ +// run + +// Copyright 2009 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. + +// Test concurrency primitives: power series. + +// Like powser1.go but uses channels of interfaces. +// Has not been cleaned up as much as powser1.go, to keep +// it distinct and therefore a different test. + +// Power series package +// A power series is a channel, along which flow rational +// coefficients. A denominator of zero signifies the end. +// Original code in Newsqueak by Doug McIlroy. +// See Squinting at Power Series by Doug McIlroy, +// https://swtch.com/~rsc/thread/squint.pdf + +package main + +import "os" + +type rat struct { + num, den int64 // numerator, denominator +} + +type item interface { + pr() + eq(c item) bool +} + +func (u *rat) pr() { + if u.den == 1 { + print(u.num) + } else { + print(u.num, "/", u.den) + } + print(" ") +} + +func (u *rat) eq(c item) bool { + c1 := c.(*rat) + return u.num == c1.num && u.den == c1.den +} + +type dch struct { + req chan int + dat chan item + nam int +} + +type dch2 [2]*dch + +var chnames string +var chnameserial int +var seqno int + +func mkdch() *dch { + c := chnameserial % len(chnames) + chnameserial++ + d := new(dch) + d.req = make(chan int) + d.dat = make(chan item) + d.nam = c + return d +} + +func mkdch2() *dch2 { + d2 := new(dch2) + d2[0] = mkdch() + d2[1] = mkdch() + return d2 +} + +// split reads a single demand channel and replicates its +// output onto two, which may be read at different rates. +// A process is created at first demand for an item and dies +// after the item has been sent to both outputs. + +// When multiple generations of split exist, the newest +// will service requests on one channel, which is +// always renamed to be out[0]; the oldest will service +// requests on the other channel, out[1]. All generations but the +// newest hold queued data that has already been sent to +// out[0]. When data has finally been sent to out[1], +// a signal on the release-wait channel tells the next newer +// generation to begin servicing out[1]. + +func dosplit(in *dch, out *dch2, wait chan int) { + both := false // do not service both channels + + select { + case <-out[0].req: + + case <-wait: + both = true + select { + case <-out[0].req: + + case <-out[1].req: + out[0], out[1] = out[1], out[0] + } + } + + seqno++ + in.req <- seqno + release := make(chan int) + go dosplit(in, out, release) + dat := <-in.dat + out[0].dat <- dat + if !both { + <-wait + } + <-out[1].req + out[1].dat <- dat + release <- 0 +} + +func split(in *dch, out *dch2) { + release := make(chan int) + go dosplit(in, out, release) + release <- 0 +} + +func put(dat item, out *dch) { + <-out.req + out.dat <- dat +} + +func get(in *dch) *rat { + seqno++ + in.req <- seqno + return (<-in.dat).(*rat) +} + +// Get one item from each of n demand channels + +func getn(in []*dch) []item { + n := len(in) + if n != 2 { + panic("bad n in getn") + } + req := make([]chan int, 2) + dat := make([]chan item, 2) + out := make([]item, 2) + var i int + var it item + for i = 0; i < n; i++ { + req[i] = in[i].req + dat[i] = nil + } + for n = 2 * n; n > 0; n-- { + seqno++ + + select { + case req[0] <- seqno: + dat[0] = in[0].dat + req[0] = nil + case req[1] <- seqno: + dat[1] = in[1].dat + req[1] = nil + case it = <-dat[0]: + out[0] = it + dat[0] = nil + case it = <-dat[1]: + out[1] = it + dat[1] = nil + } + } + return out +} + +// Get one item from each of 2 demand channels + +func get2(in0 *dch, in1 *dch) []item { + return getn([]*dch{in0, in1}) +} + +func copy(in *dch, out *dch) { + for { + <-out.req + out.dat <- get(in) + } +} + +func repeat(dat item, out *dch) { + for { + put(dat, out) + } +} + +type PS *dch // power series +type PS2 *[2]PS // pair of power series + +var Ones PS +var Twos PS + +func mkPS() *dch { + return mkdch() +} + +func mkPS2() *dch2 { + return mkdch2() +} + +// Conventions +// Upper-case for power series. +// Lower-case for rationals. +// Input variables: U,V,... +// Output variables: ...,Y,Z + +// Integer gcd; needed for rational arithmetic + +func gcd(u, v int64) int64 { + if u < 0 { + return gcd(-u, v) + } + if u == 0 { + return v + } + return gcd(v%u, u) +} + +// Make a rational from two ints and from one int + +func i2tor(u, v int64) *rat { + g := gcd(u, v) + r := new(rat) + if v > 0 { + r.num = u / g + r.den = v / g + } else { + r.num = -u / g + r.den = -v / g + } + return r +} + +func itor(u int64) *rat { + return i2tor(u, 1) +} + +var zero *rat +var one *rat + +// End mark and end test + +var finis *rat + +func end(u *rat) int64 { + if u.den == 0 { + return 1 + } + return 0 +} + +// Operations on rationals + +func add(u, v *rat) *rat { + g := gcd(u.den, v.den) + return i2tor(u.num*(v.den/g)+v.num*(u.den/g), u.den*(v.den/g)) +} + +func mul(u, v *rat) *rat { + g1 := gcd(u.num, v.den) + g2 := gcd(u.den, v.num) + r := new(rat) + r.num = (u.num / g1) * (v.num / g2) + r.den = (u.den / g2) * (v.den / g1) + return r +} + +func neg(u *rat) *rat { + return i2tor(-u.num, u.den) +} + +func sub(u, v *rat) *rat { + return add(u, neg(v)) +} + +func inv(u *rat) *rat { // invert a rat + if u.num == 0 { + panic("zero divide in inv") + } + return i2tor(u.den, u.num) +} + +// print eval in floating point of PS at x=c to n terms +func Evaln(c *rat, U PS, n int) { + xn := float64(1) + x := float64(c.num) / float64(c.den) + val := float64(0) + for i := 0; i < n; i++ { + u := get(U) + if end(u) != 0 { + break + } + val = val + x*float64(u.num)/float64(u.den) + xn = xn * x + } + print(val, "\n") +} + +// Print n terms of a power series +func Printn(U PS, n int) { + done := false + for ; !done && n > 0; n-- { + u := get(U) + if end(u) != 0 { + done = true + } else { + u.pr() + } + } + print(("\n")) +} + +func Print(U PS) { + Printn(U, 1000000000) +} + +// Evaluate n terms of power series U at x=c +func eval(c *rat, U PS, n int) *rat { + if n == 0 { + return zero + } + y := get(U) + if end(y) != 0 { + return zero + } + return add(y, mul(c, eval(c, U, n-1))) +} + +// Power-series constructors return channels on which power +// series flow. They start an encapsulated generator that +// puts the terms of the series on the channel. + +// Make a pair of power series identical to a given power series + +func Split(U PS) *dch2 { + UU := mkdch2() + go split(U, UU) + return UU +} + +// Add two power series +func Add(U, V PS) PS { + Z := mkPS() + go func(U, V, Z PS) { + var uv []item + for { + <-Z.req + uv = get2(U, V) + switch end(uv[0].(*rat)) + 2*end(uv[1].(*rat)) { + case 0: + Z.dat <- add(uv[0].(*rat), uv[1].(*rat)) + case 1: + Z.dat <- uv[1] + copy(V, Z) + case 2: + Z.dat <- uv[0] + copy(U, Z) + case 3: + Z.dat <- finis + } + } + }(U, V, Z) + return Z +} + +// Multiply a power series by a constant +func Cmul(c *rat, U PS) PS { + Z := mkPS() + go func(c *rat, U, Z PS) { + done := false + for !done { + <-Z.req + u := get(U) + if end(u) != 0 { + done = true + } else { + Z.dat <- mul(c, u) + } + } + Z.dat <- finis + }(c, U, Z) + return Z +} + +// Subtract + +func Sub(U, V PS) PS { + return Add(U, Cmul(neg(one), V)) +} + +// Multiply a power series by the monomial x^n + +func Monmul(U PS, n int) PS { + Z := mkPS() + go func(n int, U PS, Z PS) { + for ; n > 0; n-- { + put(zero, Z) + } + copy(U, Z) + }(n, U, Z) + return Z +} + +// Multiply by x + +func Xmul(U PS) PS { + return Monmul(U, 1) +} + +func Rep(c *rat) PS { + Z := mkPS() + go repeat(c, Z) + return Z +} + +// Monomial c*x^n + +func Mon(c *rat, n int) PS { + Z := mkPS() + go func(c *rat, n int, Z PS) { + if c.num != 0 { + for ; n > 0; n = n - 1 { + put(zero, Z) + } + put(c, Z) + } + put(finis, Z) + }(c, n, Z) + return Z +} + +func Shift(c *rat, U PS) PS { + Z := mkPS() + go func(c *rat, U, Z PS) { + put(c, Z) + copy(U, Z) + }(c, U, Z) + return Z +} + +// simple pole at 1: 1/(1-x) = 1 1 1 1 1 ... + +// Convert array of coefficients, constant term first +// to a (finite) power series + +/* +func Poly(a [] *rat) PS{ + Z:=mkPS() + begin func(a [] *rat, Z PS){ + j:=0 + done:=0 + for j=len(a); !done&&j>0; j=j-1) + if(a[j-1].num!=0) done=1 + i:=0 + for(; i<j; i=i+1) put(a[i],Z) + put(finis,Z) + }() + return Z +} +*/ + +// Multiply. The algorithm is +// let U = u + x*UU +// let V = v + x*VV +// then UV = u*v + x*(u*VV+v*UU) + x*x*UU*VV + +func Mul(U, V PS) PS { + Z := mkPS() + go func(U, V, Z PS) { + <-Z.req + uv := get2(U, V) + if end(uv[0].(*rat)) != 0 || end(uv[1].(*rat)) != 0 { + Z.dat <- finis + } else { + Z.dat <- mul(uv[0].(*rat), uv[1].(*rat)) + UU := Split(U) + VV := Split(V) + W := Add(Cmul(uv[0].(*rat), VV[0]), Cmul(uv[1].(*rat), UU[0])) + <-Z.req + Z.dat <- get(W) + copy(Add(W, Mul(UU[1], VV[1])), Z) + } + }(U, V, Z) + return Z +} + +// Differentiate + +func Diff(U PS) PS { + Z := mkPS() + go func(U, Z PS) { + <-Z.req + u := get(U) + if end(u) == 0 { + done := false + for i := 1; !done; i++ { + u = get(U) + if end(u) != 0 { + done = true + } else { + Z.dat <- mul(itor(int64(i)), u) + <-Z.req + } + } + } + Z.dat <- finis + }(U, Z) + return Z +} + +// Integrate, with const of integration +func Integ(c *rat, U PS) PS { + Z := mkPS() + go func(c *rat, U, Z PS) { + put(c, Z) + done := false + for i := 1; !done; i++ { + <-Z.req + u := get(U) + if end(u) != 0 { + done = true + } + Z.dat <- mul(i2tor(1, int64(i)), u) + } + Z.dat <- finis + }(c, U, Z) + return Z +} + +// Binomial theorem (1+x)^c + +func Binom(c *rat) PS { + Z := mkPS() + go func(c *rat, Z PS) { + n := 1 + t := itor(1) + for c.num != 0 { + put(t, Z) + t = mul(mul(t, c), i2tor(1, int64(n))) + c = sub(c, one) + n++ + } + put(finis, Z) + }(c, Z) + return Z +} + +// Reciprocal of a power series +// let U = u + x*UU +// let Z = z + x*ZZ +// (u+x*UU)*(z+x*ZZ) = 1 +// z = 1/u +// u*ZZ + z*UU +x*UU*ZZ = 0 +// ZZ = -UU*(z+x*ZZ)/u + +func Recip(U PS) PS { + Z := mkPS() + go func(U, Z PS) { + ZZ := mkPS2() + <-Z.req + z := inv(get(U)) + Z.dat <- z + split(Mul(Cmul(neg(z), U), Shift(z, ZZ[0])), ZZ) + copy(ZZ[1], Z) + }(U, Z) + return Z +} + +// Exponential of a power series with constant term 0 +// (nonzero constant term would make nonrational coefficients) +// bug: the constant term is simply ignored +// Z = exp(U) +// DZ = Z*DU +// integrate to get Z + +func Exp(U PS) PS { + ZZ := mkPS2() + split(Integ(one, Mul(ZZ[0], Diff(U))), ZZ) + return ZZ[1] +} + +// Substitute V for x in U, where the leading term of V is zero +// let U = u + x*UU +// let V = v + x*VV +// then S(U,V) = u + VV*S(V,UU) +// bug: a nonzero constant term is ignored + +func Subst(U, V PS) PS { + Z := mkPS() + go func(U, V, Z PS) { + VV := Split(V) + <-Z.req + u := get(U) + Z.dat <- u + if end(u) == 0 { + if end(get(VV[0])) != 0 { + put(finis, Z) + } else { + copy(Mul(VV[0], Subst(U, VV[1])), Z) + } + } + }(U, V, Z) + return Z +} + +// Monomial Substitution: U(c x^n) +// Each Ui is multiplied by c^i and followed by n-1 zeros + +func MonSubst(U PS, c0 *rat, n int) PS { + Z := mkPS() + go func(U, Z PS, c0 *rat, n int) { + c := one + for { + <-Z.req + u := get(U) + Z.dat <- mul(u, c) + c = mul(c, c0) + if end(u) != 0 { + Z.dat <- finis + break + } + for i := 1; i < n; i++ { + <-Z.req + Z.dat <- zero + } + } + }(U, Z, c0, n) + return Z +} + +func Init() { + chnameserial = -1 + seqno = 0 + chnames = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz" + zero = itor(0) + one = itor(1) + finis = i2tor(1, 0) + Ones = Rep(one) + Twos = Rep(itor(2)) +} + +func check(U PS, c *rat, count int, str string) { + for i := 0; i < count; i++ { + r := get(U) + if !r.eq(c) { + print("got: ") + r.pr() + print("should get ") + c.pr() + print("\n") + panic(str) + } + } +} + +const N = 10 + +func checka(U PS, a []*rat, str string) { + for i := 0; i < N; i++ { + check(U, a[i], 1, str) + } +} + +func main() { + Init() + if len(os.Args) > 1 { // print + print("Ones: ") + Printn(Ones, 10) + print("Twos: ") + Printn(Twos, 10) + print("Add: ") + Printn(Add(Ones, Twos), 10) + print("Diff: ") + Printn(Diff(Ones), 10) + print("Integ: ") + Printn(Integ(zero, Ones), 10) + print("CMul: ") + Printn(Cmul(neg(one), Ones), 10) + print("Sub: ") + Printn(Sub(Ones, Twos), 10) + print("Mul: ") + Printn(Mul(Ones, Ones), 10) + print("Exp: ") + Printn(Exp(Ones), 15) + print("MonSubst: ") + Printn(MonSubst(Ones, neg(one), 2), 10) + print("ATan: ") + Printn(Integ(zero, MonSubst(Ones, neg(one), 2)), 10) + } else { // test + check(Ones, one, 5, "Ones") + check(Add(Ones, Ones), itor(2), 0, "Add Ones Ones") // 1 1 1 1 1 + check(Add(Ones, Twos), itor(3), 0, "Add Ones Twos") // 3 3 3 3 3 + a := make([]*rat, N) + d := Diff(Ones) + for i := 0; i < N; i++ { + a[i] = itor(int64(i + 1)) + } + checka(d, a, "Diff") // 1 2 3 4 5 + in := Integ(zero, Ones) + a[0] = zero // integration constant + for i := 1; i < N; i++ { + a[i] = i2tor(1, int64(i)) + } + checka(in, a, "Integ") // 0 1 1/2 1/3 1/4 1/5 + check(Cmul(neg(one), Twos), itor(-2), 10, "CMul") // -1 -1 -1 -1 -1 + check(Sub(Ones, Twos), itor(-1), 0, "Sub Ones Twos") // -1 -1 -1 -1 -1 + m := Mul(Ones, Ones) + for i := 0; i < N; i++ { + a[i] = itor(int64(i + 1)) + } + checka(m, a, "Mul") // 1 2 3 4 5 + e := Exp(Ones) + a[0] = itor(1) + a[1] = itor(1) + a[2] = i2tor(3, 2) + a[3] = i2tor(13, 6) + a[4] = i2tor(73, 24) + a[5] = i2tor(167, 40) + a[6] = i2tor(4051, 720) + a[7] = i2tor(37633, 5040) + a[8] = i2tor(43817, 4480) + a[9] = i2tor(4596553, 362880) + checka(e, a, "Exp") // 1 1 3/2 13/6 73/24 + at := Integ(zero, MonSubst(Ones, neg(one), 2)) + for c, i := 1, 0; i < N; i++ { + if i%2 == 0 { + a[i] = zero + } else { + a[i] = i2tor(int64(c), int64(i)) + c *= -1 + } + } + checka(at, a, "ATan") // 0 -1 0 -1/3 0 -1/5 + /* + t := Revert(Integ(zero, MonSubst(Ones, neg(one), 2))) + a[0] = zero + a[1] = itor(1) + a[2] = zero + a[3] = i2tor(1,3) + a[4] = zero + a[5] = i2tor(2,15) + a[6] = zero + a[7] = i2tor(17,315) + a[8] = zero + a[9] = i2tor(62,2835) + checka(t, a, "Tan") // 0 1 0 1/3 0 2/15 + */ + } +} diff --git a/test/chan/select.go b/test/chan/select.go new file mode 100644 index 0000000..38fa7e1 --- /dev/null +++ b/test/chan/select.go @@ -0,0 +1,58 @@ +// run + +// Copyright 2009 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. + +// Test simple select. + +package main + +var counter uint +var shift uint + +func GetValue() uint { + counter++ + return 1 << shift +} + +func Send(a, b chan uint) int { + var i int + +LOOP: + for { + select { + case a <- GetValue(): + i++ + a = nil + case b <- GetValue(): + i++ + b = nil + default: + break LOOP + } + shift++ + } + return i +} + +func main() { + a := make(chan uint, 1) + b := make(chan uint, 1) + if v := Send(a, b); v != 2 { + println("Send returned", v, "!= 2") + panic("fail") + } + if av, bv := <-a, <-b; av|bv != 3 { + println("bad values", av, bv) + panic("fail") + } + if v := Send(a, nil); v != 1 { + println("Send returned", v, "!= 1") + panic("fail") + } + if counter != 10 { + println("counter is", counter, "!= 10") + panic("fail") + } +} diff --git a/test/chan/select2.go b/test/chan/select2.go new file mode 100644 index 0000000..31e27d7 --- /dev/null +++ b/test/chan/select2.go @@ -0,0 +1,54 @@ +// run + +// 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. + +// Test that selects do not consume undue memory. + +package main + +import "runtime" + +func sender(c chan int, n int) { + for i := 0; i < n; i++ { + c <- 1 + } +} + +func receiver(c, dummy chan int, n int) { + for i := 0; i < n; i++ { + select { + case <-c: + // nothing + case <-dummy: + panic("dummy") + } + } +} + +func main() { + runtime.MemProfileRate = 0 + + c := make(chan int) + dummy := make(chan int) + + // warm up + go sender(c, 100000) + receiver(c, dummy, 100000) + runtime.GC() + memstats := new(runtime.MemStats) + runtime.ReadMemStats(memstats) + alloc := memstats.Alloc + + // second time shouldn't increase footprint by much + go sender(c, 100000) + receiver(c, dummy, 100000) + runtime.GC() + runtime.ReadMemStats(memstats) + + // Be careful to avoid wraparound. + if memstats.Alloc > alloc && memstats.Alloc-alloc > 1.1e5 { + println("BUG: too much memory for 100,000 selects:", memstats.Alloc-alloc) + } +} diff --git a/test/chan/select3.go b/test/chan/select3.go new file mode 100644 index 0000000..dd14c73 --- /dev/null +++ b/test/chan/select3.go @@ -0,0 +1,226 @@ +// run + +// 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. + +// Test the semantics of the select statement +// for basic empty/non-empty cases. + +package main + +import "time" + +const always = "function did not" +const never = "function did" + +func unreachable() { + panic("control flow shouldn't reach here") +} + +// Calls f and verifies that f always/never panics depending on signal. +func testPanic(signal string, f func()) { + defer func() { + s := never + if recover() != nil { + s = always // f panicked + } + if s != signal { + panic(signal + " panic") + } + }() + f() +} + +// Calls f and empirically verifies that f always/never blocks depending on signal. +func testBlock(signal string, f func()) { + c := make(chan string) + go func() { + f() + c <- never // f didn't block + }() + go func() { + if signal == never { + // Wait a long time to make sure that we don't miss our window by accident on a slow machine. + time.Sleep(10 * time.Second) + } else { + // Wait as short a time as we can without false negatives. + // 10ms should be long enough to catch most failures. + time.Sleep(10 * time.Millisecond) + } + c <- always // f blocked always + }() + if <-c != signal { + panic(signal + " block") + } +} + +func main() { + const async = 1 // asynchronous channels + var nilch chan int + closedch := make(chan int) + close(closedch) + + // sending/receiving from a nil channel blocks + testBlock(always, func() { + nilch <- 7 + }) + testBlock(always, func() { + <-nilch + }) + + // sending/receiving from a nil channel inside a select is never selected + testPanic(never, func() { + select { + case nilch <- 7: + unreachable() + default: + } + }) + testPanic(never, func() { + select { + case <-nilch: + unreachable() + default: + } + }) + + // sending to an async channel with free buffer space never blocks + testBlock(never, func() { + ch := make(chan int, async) + ch <- 7 + }) + + // receiving from a closed channel never blocks + testBlock(never, func() { + for i := 0; i < 10; i++ { + if <-closedch != 0 { + panic("expected zero value when reading from closed channel") + } + if x, ok := <-closedch; x != 0 || ok { + println("closedch:", x, ok) + panic("expected 0, false from closed channel") + } + } + }) + + // sending to a closed channel panics. + testPanic(always, func() { + closedch <- 7 + }) + + // receiving from a non-ready channel always blocks + testBlock(always, func() { + ch := make(chan int) + <-ch + }) + + // empty selects always block + testBlock(always, func() { + select {} + }) + + // selects with only nil channels always block + testBlock(always, func() { + select { + case <-nilch: + unreachable() + } + }) + testBlock(always, func() { + select { + case nilch <- 7: + unreachable() + } + }) + testBlock(always, func() { + select { + case <-nilch: + unreachable() + case nilch <- 7: + unreachable() + } + }) + + // selects with non-ready non-nil channels always block + testBlock(always, func() { + ch := make(chan int) + select { + case <-ch: + unreachable() + } + }) + + // selects with default cases don't block + testBlock(never, func() { + select { + default: + } + }) + testBlock(never, func() { + select { + case <-nilch: + unreachable() + default: + } + }) + testBlock(never, func() { + select { + case nilch <- 7: + unreachable() + default: + } + }) + + // selects with ready channels don't block + testBlock(never, func() { + ch := make(chan int, async) + select { + case ch <- 7: + default: + unreachable() + } + }) + testBlock(never, func() { + ch := make(chan int, async) + ch <- 7 + select { + case <-ch: + default: + unreachable() + } + }) + + // selects with closed channels behave like ordinary operations + testBlock(never, func() { + select { + case <-closedch: + } + }) + testBlock(never, func() { + select { + case x := (<-closedch): + _ = x + } + }) + testBlock(never, func() { + select { + case x, ok := (<-closedch): + _, _ = x, ok + } + }) + testPanic(always, func() { + select { + case closedch <- 7: + } + }) + + // select should not get confused if it sees itself + testBlock(always, func() { + c := make(chan int) + select { + case c <- 1: + case <-c: + } + }) +} diff --git a/test/chan/select4.go b/test/chan/select4.go new file mode 100644 index 0000000..5003640 --- /dev/null +++ b/test/chan/select4.go @@ -0,0 +1,31 @@ +// run + +// 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 + +// Test that a select statement proceeds when a value is ready. + +package main + +func f() *int { + println("BUG: called f") + return new(int) +} + +func main() { + var x struct { + a int + } + c := make(chan int, 1) + c1 := make(chan int) + c <- 42 + select { + case *f() = <-c1: + // nothing + case x.a = <-c: + if x.a != 42 { + println("BUG:", x.a) + } + } +} diff --git a/test/chan/select5.go b/test/chan/select5.go new file mode 100644 index 0000000..8b98c3a --- /dev/null +++ b/test/chan/select5.go @@ -0,0 +1,481 @@ +// runoutput + +// Copyright 2011 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. + +// Generate test of channel operations and simple selects. +// The output of this program is compiled and run to do the +// actual test. + +// Each test does only one real send or receive at a time, but phrased +// in various ways that the compiler may or may not rewrite +// into simpler expressions. + +package main + +import ( + "bufio" + "fmt" + "io" + "os" + "text/template" +) + +func main() { + out := bufio.NewWriter(os.Stdout) + fmt.Fprintln(out, header) + a := new(arg) + + // Generate each test as a separate function to avoid + // hitting the gc optimizer with one enormous function. + // If we name all the functions init we don't have to + // maintain a list of which ones to run. + do := func(t *template.Template) { + for ; next(); a.reset() { + fmt.Fprintln(out, `func init() {`) + run(t, a, out) + fmt.Fprintln(out, `}`) + } + } + + do(recv) + do(send) + do(recvOrder) + do(sendOrder) + do(nonblock) + + fmt.Fprintln(out, "//", a.nreset, "cases") + out.Flush() +} + +func run(t *template.Template, a interface{}, out io.Writer) { + if err := t.Execute(out, a); err != nil { + panic(err) + } +} + +type arg struct { + def bool + nreset int +} + +func (a *arg) Maybe() bool { + return maybe() +} + +func (a *arg) MaybeDefault() bool { + if a.def { + return false + } + a.def = maybe() + return a.def +} + +func (a *arg) MustDefault() bool { + return !a.def +} + +func (a *arg) reset() { + a.def = false + a.nreset++ +} + +const header = `// GENERATED BY select5.go; DO NOT EDIT + +package main + +// channel is buffered so test is single-goroutine. +// we are not interested in the concurrency aspects +// of select, just testing that the right calls happen. +var c = make(chan int, 1) +var nilch chan int +var n = 1 +var x int +var i interface{} +var dummy = make(chan int) +var m = make(map[int]int) +var order = 0 + +func f(p *int) *int { + return p +} + +// check order of operations by ensuring that +// successive calls to checkorder have increasing o values. +func checkorder(o int) { + if o <= order { + println("invalid order", o, "after", order) + panic("order") + } + order = o +} + +func fc(c chan int, o int) chan int { + checkorder(o) + return c +} + +func fp(p *int, o int) *int { + checkorder(o) + return p +} + +func fn(n, o int) int { + checkorder(o) + return n +} + +func die(x int) { + println("have", x, "want", n) + panic("chan") +} + +func main() { + // everything happens in init funcs +} +` + +func parse(name, s string) *template.Template { + t, err := template.New(name).Parse(s) + if err != nil { + panic(fmt.Sprintf("%q: %s", name, err)) + } + return t +} + +var recv = parse("recv", ` + {{/* Send n, receive it one way or another into x, check that they match. */}} + c <- n + {{if .Maybe}} + x = <-c + {{else}} + select { + {{/* Blocking or non-blocking, before the receive. */}} + {{/* The compiler implements two-case select where one is default with custom code, */}} + {{/* so test the default branch both before and after the send. */}} + {{if .MaybeDefault}} + default: + panic("nonblock") + {{end}} + {{/* Receive from c. Different cases are direct, indirect, :=, interface, and map assignment. */}} + {{if .Maybe}} + case x = <-c: + {{else}}{{if .Maybe}} + case *f(&x) = <-c: + {{else}}{{if .Maybe}} + case y := <-c: + x = y + {{else}}{{if .Maybe}} + case i = <-c: + x = i.(int) + {{else}} + case m[13] = <-c: + x = m[13] + {{end}}{{end}}{{end}}{{end}} + {{/* Blocking or non-blocking again, after the receive. */}} + {{if .MaybeDefault}} + default: + panic("nonblock") + {{end}} + {{/* Dummy send, receive to keep compiler from optimizing select. */}} + {{if .Maybe}} + case dummy <- 1: + panic("dummy send") + {{end}} + {{if .Maybe}} + case <-dummy: + panic("dummy receive") + {{end}} + {{/* Nil channel send, receive to keep compiler from optimizing select. */}} + {{if .Maybe}} + case nilch <- 1: + panic("nilch send") + {{end}} + {{if .Maybe}} + case <-nilch: + panic("nilch recv") + {{end}} + } + {{end}} + if x != n { + die(x) + } + n++ +`) + +var recvOrder = parse("recvOrder", ` + {{/* Send n, receive it one way or another into x, check that they match. */}} + {{/* Check order of operations along the way by calling functions that check */}} + {{/* that the argument sequence is strictly increasing. */}} + order = 0 + c <- n + {{if .Maybe}} + {{/* Outside of select, left-to-right rule applies. */}} + {{/* (Inside select, assignment waits until case is chosen, */}} + {{/* so right hand side happens before anything on left hand side. */}} + *fp(&x, 1) = <-fc(c, 2) + {{else}}{{if .Maybe}} + m[fn(13, 1)] = <-fc(c, 2) + x = m[13] + {{else}} + select { + {{/* Blocking or non-blocking, before the receive. */}} + {{/* The compiler implements two-case select where one is default with custom code, */}} + {{/* so test the default branch both before and after the send. */}} + {{if .MaybeDefault}} + default: + panic("nonblock") + {{end}} + {{/* Receive from c. Different cases are direct, indirect, :=, interface, and map assignment. */}} + {{if .Maybe}} + case *fp(&x, 100) = <-fc(c, 1): + {{else}}{{if .Maybe}} + case y := <-fc(c, 1): + x = y + {{else}}{{if .Maybe}} + case i = <-fc(c, 1): + x = i.(int) + {{else}} + case m[fn(13, 100)] = <-fc(c, 1): + x = m[13] + {{end}}{{end}}{{end}} + {{/* Blocking or non-blocking again, after the receive. */}} + {{if .MaybeDefault}} + default: + panic("nonblock") + {{end}} + {{/* Dummy send, receive to keep compiler from optimizing select. */}} + {{if .Maybe}} + case fc(dummy, 2) <- fn(1, 3): + panic("dummy send") + {{end}} + {{if .Maybe}} + case <-fc(dummy, 4): + panic("dummy receive") + {{end}} + {{/* Nil channel send, receive to keep compiler from optimizing select. */}} + {{if .Maybe}} + case fc(nilch, 5) <- fn(1, 6): + panic("nilch send") + {{end}} + {{if .Maybe}} + case <-fc(nilch, 7): + panic("nilch recv") + {{end}} + } + {{end}}{{end}} + if x != n { + die(x) + } + n++ +`) + +var send = parse("send", ` + {{/* Send n one way or another, receive it into x, check that they match. */}} + {{if .Maybe}} + c <- n + {{else}} + select { + {{/* Blocking or non-blocking, before the receive (same reason as in recv). */}} + {{if .MaybeDefault}} + default: + panic("nonblock") + {{end}} + {{/* Send c <- n. No real special cases here, because no values come back */}} + {{/* from the send operation. */}} + case c <- n: + {{/* Blocking or non-blocking. */}} + {{if .MaybeDefault}} + default: + panic("nonblock") + {{end}} + {{/* Dummy send, receive to keep compiler from optimizing select. */}} + {{if .Maybe}} + case dummy <- 1: + panic("dummy send") + {{end}} + {{if .Maybe}} + case <-dummy: + panic("dummy receive") + {{end}} + {{/* Nil channel send, receive to keep compiler from optimizing select. */}} + {{if .Maybe}} + case nilch <- 1: + panic("nilch send") + {{end}} + {{if .Maybe}} + case <-nilch: + panic("nilch recv") + {{end}} + } + {{end}} + x = <-c + if x != n { + die(x) + } + n++ +`) + +var sendOrder = parse("sendOrder", ` + {{/* Send n one way or another, receive it into x, check that they match. */}} + {{/* Check order of operations along the way by calling functions that check */}} + {{/* that the argument sequence is strictly increasing. */}} + order = 0 + {{if .Maybe}} + fc(c, 1) <- fn(n, 2) + {{else}} + select { + {{/* Blocking or non-blocking, before the receive (same reason as in recv). */}} + {{if .MaybeDefault}} + default: + panic("nonblock") + {{end}} + {{/* Send c <- n. No real special cases here, because no values come back */}} + {{/* from the send operation. */}} + case fc(c, 1) <- fn(n, 2): + {{/* Blocking or non-blocking. */}} + {{if .MaybeDefault}} + default: + panic("nonblock") + {{end}} + {{/* Dummy send, receive to keep compiler from optimizing select. */}} + {{if .Maybe}} + case fc(dummy, 3) <- fn(1, 4): + panic("dummy send") + {{end}} + {{if .Maybe}} + case <-fc(dummy, 5): + panic("dummy receive") + {{end}} + {{/* Nil channel send, receive to keep compiler from optimizing select. */}} + {{if .Maybe}} + case fc(nilch, 6) <- fn(1, 7): + panic("nilch send") + {{end}} + {{if .Maybe}} + case <-fc(nilch, 8): + panic("nilch recv") + {{end}} + } + {{end}} + x = <-c + if x != n { + die(x) + } + n++ +`) + +var nonblock = parse("nonblock", ` + x = n + {{/* Test various combinations of non-blocking operations. */}} + {{/* Receive assignments must not edit or even attempt to compute the address of the lhs. */}} + select { + {{if .MaybeDefault}} + default: + {{end}} + {{if .Maybe}} + case dummy <- 1: + panic("dummy <- 1") + {{end}} + {{if .Maybe}} + case nilch <- 1: + panic("nilch <- 1") + {{end}} + {{if .Maybe}} + case <-dummy: + panic("<-dummy") + {{end}} + {{if .Maybe}} + case x = <-dummy: + panic("<-dummy x") + {{end}} + {{if .Maybe}} + case **(**int)(nil) = <-dummy: + panic("<-dummy (and didn't crash saving result!)") + {{end}} + {{if .Maybe}} + case <-nilch: + panic("<-nilch") + {{end}} + {{if .Maybe}} + case x = <-nilch: + panic("<-nilch x") + {{end}} + {{if .Maybe}} + case **(**int)(nil) = <-nilch: + panic("<-nilch (and didn't crash saving result!)") + {{end}} + {{if .MustDefault}} + default: + {{end}} + } + if x != n { + die(x) + } + n++ +`) + +// Code for enumerating all possible paths through +// some logic. The logic should call choose(n) when +// it wants to choose between n possibilities. +// On successive runs through the logic, choose(n) +// will return 0, 1, ..., n-1. The helper maybe() is +// similar but returns true and then false. +// +// Given a function gen that generates an output +// using choose and maybe, code can generate all +// possible outputs using +// +// for next() { +// gen() +// } + +type choice struct { + i, n int +} + +var choices []choice +var cp int = -1 + +func maybe() bool { + return choose(2) == 0 +} + +func choose(n int) int { + if cp >= len(choices) { + // never asked this before: start with 0. + choices = append(choices, choice{0, n}) + cp = len(choices) + return 0 + } + // otherwise give recorded answer + if n != choices[cp].n { + panic("inconsistent choices") + } + i := choices[cp].i + cp++ + return i +} + +func next() bool { + if cp < 0 { + // start a new round + cp = 0 + return true + } + + // increment last choice sequence + cp = len(choices) - 1 + for cp >= 0 && choices[cp].i == choices[cp].n-1 { + cp-- + } + if cp < 0 { + choices = choices[:0] + return false + } + choices[cp].i++ + choices = choices[:cp+1] + cp = 0 + return true +} diff --git a/test/chan/select6.go b/test/chan/select6.go new file mode 100644 index 0000000..6e8129f --- /dev/null +++ b/test/chan/select6.go @@ -0,0 +1,34 @@ +// run + +// Copyright 2011 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. + +// Test for select: Issue 2075 +// A bug in select corrupts channel queues of failed cases +// if there are multiple waiters on those channels and the +// select is the last in the queue. If further waits are made +// on the channel without draining it first then those waiters +// will never wake up. In the code below c1 is such a channel. + +package main + +func main() { + c1 := make(chan bool) + c2 := make(chan bool) + c3 := make(chan bool) + go func() { <-c1 }() + go func() { + select { + case <-c1: + panic("dummy") + case <-c2: + c3 <- true + } + <-c1 + }() + go func() { c2 <- true }() + <-c3 + c1 <- true + c1 <- true +} diff --git a/test/chan/select7.go b/test/chan/select7.go new file mode 100644 index 0000000..f7222ca --- /dev/null +++ b/test/chan/select7.go @@ -0,0 +1,68 @@ +// run + +// Copyright 2011 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. + +// Test select when discarding a value. + +package main + +import "runtime" + +func recv1(c <-chan int) { + <-c +} + +func recv2(c <-chan int) { + select { + case <-c: + } +} + +func recv3(c <-chan int) { + c2 := make(chan int) + select { + case <-c: + case <-c2: + } +} + +func send1(recv func(<-chan int)) { + c := make(chan int) + go recv(c) + runtime.Gosched() + c <- 1 +} + +func send2(recv func(<-chan int)) { + c := make(chan int) + go recv(c) + runtime.Gosched() + select { + case c <- 1: + } +} + +func send3(recv func(<-chan int)) { + c := make(chan int) + go recv(c) + runtime.Gosched() + c2 := make(chan int) + select { + case c <- 1: + case c2 <- 1: + } +} + +func main() { + send1(recv1) + send2(recv1) + send3(recv1) + send1(recv2) + send2(recv2) + send3(recv2) + send1(recv3) + send2(recv3) + send3(recv3) +} diff --git a/test/chan/select8.go b/test/chan/select8.go new file mode 100644 index 0000000..20bca3a --- /dev/null +++ b/test/chan/select8.go @@ -0,0 +1,55 @@ +// run + +// Copyright 2019 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. + +// Test break statements in a select. +// Gccgo had a bug in handling this. +// Test 1,2,3-case selects, so it covers both the general +// code path and the specialized optimizations for one- +// and two-case selects. + +package main + +var ch = make(chan int) + +func main() { + go func() { + for { + ch <- 5 + } + }() + + select { + case <-ch: + break + panic("unreachable") + } + + select { + default: + break + panic("unreachable") + } + + select { + case <-ch: + break + panic("unreachable") + default: + break + panic("unreachable") + } + + select { + case <-ch: + break + panic("unreachable") + case ch <- 10: + panic("unreachable") + default: + break + panic("unreachable") + } +} diff --git a/test/chan/sendstmt.go b/test/chan/sendstmt.go new file mode 100644 index 0000000..d296a55 --- /dev/null +++ b/test/chan/sendstmt.go @@ -0,0 +1,37 @@ +// run + +// Copyright 2011 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. + +// Test various parsing cases that are a little +// different now that send is a statement, not an expression. + +package main + +func main() { + chanchan() + sendprec() +} + +func chanchan() { + cc := make(chan chan int, 1) + c := make(chan int, 1) + cc <- c + select { + case <-cc <- 2: + default: + panic("nonblock") + } + if <-c != 2 { + panic("bad receive") + } +} + +func sendprec() { + c := make(chan bool, 1) + c <- false || true // not a syntax error: same as c <- (false || true) + if !<-c { + panic("sent false") + } +} diff --git a/test/chan/sieve1.go b/test/chan/sieve1.go new file mode 100644 index 0000000..acc310f --- /dev/null +++ b/test/chan/sieve1.go @@ -0,0 +1,56 @@ +// run + +// Copyright 2009 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. + +// Test concurrency primitives: classical inefficient concurrent prime sieve. + +// Generate primes up to 100 using channels, checking the results. +// This sieve consists of a linear chain of divisibility filters, +// equivalent to trial-dividing each n by all primes p ≤ n. + +package main + +// Send the sequence 2, 3, 4, ... to channel 'ch'. +func Generate(ch chan<- int) { + for i := 2; ; i++ { + ch <- i // Send 'i' to channel 'ch'. + } +} + +// Copy the values from channel 'in' to channel 'out', +// removing those divisible by 'prime'. +func Filter(in <-chan int, out chan<- int, prime int) { + for i := range in { // Loop over values received from 'in'. + if i%prime != 0 { + out <- i // Send 'i' to channel 'out'. + } + } +} + +// The prime sieve: Daisy-chain Filter processes together. +func Sieve(primes chan<- int) { + ch := make(chan int) // Create a new channel. + go Generate(ch) // Start Generate() as a subprocess. + for { + // Note that ch is different on each iteration. + prime := <-ch + primes <- prime + ch1 := make(chan int) + go Filter(ch, ch1, prime) + ch = ch1 + } +} + +func main() { + primes := make(chan int) + go Sieve(primes) + a := []int{2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97} + for i := 0; i < len(a); i++ { + if x := <-primes; x != a[i] { + println(x, " != ", a[i]) + panic("fail") + } + } +} diff --git a/test/chan/sieve2.go b/test/chan/sieve2.go new file mode 100644 index 0000000..09e5c52 --- /dev/null +++ b/test/chan/sieve2.go @@ -0,0 +1,188 @@ +// run + +// Copyright 2009 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. + +// Test concurrency primitives: prime sieve of Eratosthenes. + +// Generate primes up to 100 using channels, checking the results. +// This sieve is Eratosthenesque and only considers odd candidates. +// See discussion at <http://blog.onideas.ws/eratosthenes.go>. + +package main + +import ( + "container/heap" + "container/ring" +) + +// Return a chan of odd numbers, starting from 5. +func odds() chan int { + out := make(chan int, 50) + go func() { + n := 5 + for { + out <- n + n += 2 + } + }() + return out +} + +// Return a chan of odd multiples of the prime number p, starting from p*p. +func multiples(p int) chan int { + out := make(chan int, 10) + go func() { + n := p * p + for { + out <- n + n += 2 * p + } + }() + return out +} + +type PeekCh struct { + head int + ch chan int +} + +// Heap of PeekCh, sorting by head values, satisfies Heap interface. +type PeekChHeap []*PeekCh + +func (h *PeekChHeap) Less(i, j int) bool { + return (*h)[i].head < (*h)[j].head +} + +func (h *PeekChHeap) Swap(i, j int) { + (*h)[i], (*h)[j] = (*h)[j], (*h)[i] +} + +func (h *PeekChHeap) Len() int { + return len(*h) +} + +func (h *PeekChHeap) Pop() (v interface{}) { + *h, v = (*h)[:h.Len()-1], (*h)[h.Len()-1] + return +} + +func (h *PeekChHeap) Push(v interface{}) { + *h = append(*h, v.(*PeekCh)) +} + +// Return a channel to serve as a sending proxy to 'out'. +// Use a goroutine to receive values from 'out' and store them +// in an expanding buffer, so that sending to 'out' never blocks. +func sendproxy(out chan<- int) chan<- int { + proxy := make(chan int, 10) + go func() { + n := 16 // the allocated size of the circular queue + first := ring.New(n) + last := first + var c chan<- int + var e int + for { + c = out + if first == last { + // buffer empty: disable output + c = nil + } else { + e = first.Value.(int) + } + select { + case e = <-proxy: + last.Value = e + if last.Next() == first { + // buffer full: expand it + last.Link(ring.New(n)) + n *= 2 + } + last = last.Next() + case c <- e: + first = first.Next() + } + } + }() + return proxy +} + +// Return a chan int of primes. +func Sieve() chan int { + // The output values. + out := make(chan int, 10) + out <- 2 + out <- 3 + + // The channel of all composites to be eliminated in increasing order. + composites := make(chan int, 50) + + // The feedback loop. + primes := make(chan int, 10) + primes <- 3 + + // Merge channels of multiples of 'primes' into 'composites'. + go func() { + var h PeekChHeap + min := 15 + for { + m := multiples(<-primes) + head := <-m + for min < head { + composites <- min + minchan := heap.Pop(&h).(*PeekCh) + min = minchan.head + minchan.head = <-minchan.ch + heap.Push(&h, minchan) + } + for min == head { + minchan := heap.Pop(&h).(*PeekCh) + min = minchan.head + minchan.head = <-minchan.ch + heap.Push(&h, minchan) + } + composites <- head + heap.Push(&h, &PeekCh{<-m, m}) + } + }() + + // Sieve out 'composites' from 'candidates'. + go func() { + // In order to generate the nth prime we only need multiples of + // primes ≤ sqrt(nth prime). Thus, the merging goroutine will + // receive from 'primes' much slower than this goroutine + // will send to it, making the buffer accumulate and block this + // goroutine from sending, causing a deadlock. The solution is to + // use a proxy goroutine to do automatic buffering. + primes := sendproxy(primes) + + candidates := odds() + p := <-candidates + + for { + c := <-composites + for p < c { + primes <- p + out <- p + p = <-candidates + } + if p == c { + p = <-candidates + } + } + }() + + return out +} + +func main() { + primes := Sieve() + a := []int{2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97} + for i := 0; i < len(a); i++ { + if x := <-primes; x != a[i] { + println(x, " != ", a[i]) + panic("fail") + } + } +} diff --git a/test/chan/zerosize.go b/test/chan/zerosize.go new file mode 100644 index 0000000..50aca85 --- /dev/null +++ b/test/chan/zerosize.go @@ -0,0 +1,16 @@ +// run + +// Copyright 2011 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. + +// Test making channels of a zero-sized type. + +package main + +func main() { + _ = make(chan [0]byte) + _ = make(chan [0]byte, 1) + _ = make(chan struct{}) + _ = make(chan struct{}, 1) +} diff --git a/test/chancap.go b/test/chancap.go new file mode 100644 index 0000000..8dce924 --- /dev/null +++ b/test/chancap.go @@ -0,0 +1,71 @@ +// run + +// Copyright 2009 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. + +// Test the cap predeclared function applied to channels. + +package main + +import ( + "strings" + "unsafe" +) + +type T chan int + +const ptrSize = unsafe.Sizeof((*byte)(nil)) + +func main() { + c := make(T, 10) + if len(c) != 0 || cap(c) != 10 { + println("chan len/cap ", len(c), cap(c), " want 0 10") + panic("fail") + } + + for i := 0; i < 3; i++ { + c <- i + } + if len(c) != 3 || cap(c) != 10 { + println("chan len/cap ", len(c), cap(c), " want 3 10") + panic("fail") + } + + c = make(T) + if len(c) != 0 || cap(c) != 0 { + println("chan len/cap ", len(c), cap(c), " want 0 0") + panic("fail") + } + + n := -1 + shouldPanic("makechan: size out of range", func() { _ = make(T, n) }) + shouldPanic("makechan: size out of range", func() { _ = make(T, int64(n)) }) + if ptrSize == 8 { + // Test mem > maxAlloc + var n2 int64 = 1 << 59 + shouldPanic("makechan: size out of range", func() { _ = make(T, int(n2)) }) + // Test elem.size*cap overflow + n2 = 1<<63 - 1 + shouldPanic("makechan: size out of range", func() { _ = make(T, int(n2)) }) + } else { + n = 1<<31 - 1 + shouldPanic("makechan: size out of range", func() { _ = make(T, n) }) + shouldPanic("makechan: size out of range", func() { _ = make(T, int64(n)) }) + } +} + +func shouldPanic(str string, f func()) { + defer func() { + err := recover() + if err == nil { + panic("did not panic") + } + s := err.(error).Error() + if !strings.Contains(s, str) { + panic("got panic " + s + ", want " + str) + } + }() + + f() +} diff --git a/test/chanlinear.go b/test/chanlinear.go new file mode 100644 index 0000000..4d55586 --- /dev/null +++ b/test/chanlinear.go @@ -0,0 +1,94 @@ +// +build darwin linux +// run + +// Copyright 2014 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. + +// Test that dequeuing from a pending channel doesn't +// take linear time. + +package main + +import ( + "fmt" + "runtime" + "time" +) + +// checkLinear asserts that the running time of f(n) is in O(n). +// tries is the initial number of iterations. +func checkLinear(typ string, tries int, f func(n int)) { + // Depending on the machine and OS, this test might be too fast + // to measure with accurate enough granularity. On failure, + // make it run longer, hoping that the timing granularity + // is eventually sufficient. + + timeF := func(n int) time.Duration { + t1 := time.Now() + f(n) + return time.Since(t1) + } + + t0 := time.Now() + + n := tries + fails := 0 + for { + runtime.GC() + t1 := timeF(n) + runtime.GC() + t2 := timeF(2 * n) + + // should be 2x (linear); allow up to 3x + if t2 < 3*t1 { + if false { + fmt.Println(typ, "\t", time.Since(t0)) + } + return + } + // If n ops run in under a second and the ratio + // doesn't work out, make n bigger, trying to reduce + // the effect that a constant amount of overhead has + // on the computed ratio. + if t1 < 1*time.Second { + n *= 2 + continue + } + // Once the test runs long enough for n ops, + // try to get the right ratio at least once. + // If five in a row all fail, give up. + if fails++; fails >= 5 { + panic(fmt.Sprintf("%s: too slow: %d channels: %v; %d channels: %v\n", + typ, n, t1, 2*n, t2)) + } + } +} + +func main() { + checkLinear("chanSelect", 1000, func(n int) { + const messages = 10 + c := make(chan bool) // global channel + var a []chan bool // local channels for each goroutine + for i := 0; i < n; i++ { + d := make(chan bool) + a = append(a, d) + go func() { + for j := 0; j < messages; j++ { + // queue ourselves on the global channel + select { + case <-c: + case <-d: + } + } + }() + } + for i := 0; i < messages; i++ { + // wake each goroutine up, forcing it to dequeue and then enqueue + // on the global channel. + for _, d := range a { + d <- true + } + } + }) +} |