X-Git-Url: http://www.git.cypherpunks.ru/?a=blobdiff_plain;f=js.go;h=701d26d39683891c0a01762758f3ce63358f1cea;hb=314f58ec690c7321535d6718e8d3a0ecb4cac019;hp=ab1190e00c00759f48899030271986704d3c9ae4;hpb=f15fe27971bcf37a06bb9542ea1907f11444515a;p=goredo.git

diff --git a/js.go b/js.go
index ab1190e..701d26d 100644
--- a/js.go
+++ b/js.go
@@ -1,6 +1,6 @@
 /*
-goredo -- redo implementation on pure Go
-Copyright (C) 2020 Sergey Matveev <stargrave@stargrave.org>
+goredo -- djb's redo implementation on pure Go
+Copyright (C) 2020-2021 Sergey Matveev <stargrave@stargrave.org>
 
 This program is free software: you can redistribute it and/or modify
 it under the terms of the GNU General Public License as published by
@@ -19,59 +19,115 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 package main
 
-import "os"
+import (
+	"flag"
+	"fmt"
+	"log"
+	"os"
+	"os/signal"
+	"strconv"
+	"strings"
+	"sync"
+	"syscall"
+)
+
+const (
+	EnvJobs = "REDO_JOBS"
+	EnvJSFd = "REDO_JS_FD"
+)
 
 var (
-	JSR *os.File
-	JSW *os.File
+	JSR       *os.File
+	JSW       *os.File
+	jsTokens  int
+	jsTokensM sync.Mutex
+
+	flagJobs = flag.Int("j", -1, fmt.Sprintf("number of parallel jobs (0=inf, <0=1) (%s)", EnvJobs))
 )
 
 func jsInit() {
-	jsrRaw := os.Getenv(RedoJSRFdEnv)
-	jswRaw := os.Getenv(RedoJSWFdEnv)
-	if (jsrRaw == "" && jswRaw != "") || (jsrRaw != "" && jswRaw == "") {
-		panic("both JSR and JSW must be set")
-	}
-	if jsrRaw == "NO" {
+	jsRaw := os.Getenv(EnvJSFd)
+	if jsRaw == "NO" {
 		// infinite jobs
 		return
 	}
-	if jsrRaw != "" {
-		JSR = mustParseFd(jsrRaw, "JSR")
-		JSW = mustParseFd(jswRaw, "JSW")
-		jsRelease()
+	if jsRaw != "" {
+		cols := strings.Split(jsRaw, ",")
+		if len(cols) != 2 {
+			log.Fatalln("invalid", EnvJSFd, "format")
+		}
+		JSR = mustParseFd(cols[0], "JSR")
+		JSW = mustParseFd(cols[1], "JSW")
+		jsRelease("ifchange entered")
+
+		killed := make(chan os.Signal, 0)
+		signal.Notify(killed, syscall.SIGTERM, syscall.SIGINT)
+		go func() {
+			<-killed
+			jsTokensM.Lock()
+			for ; jsTokens > 0; jsTokens-- {
+				jsReleaseNoLock()
+			}
+			os.Exit(1)
+		}()
 		return
 	}
-	if *JobsN == 0 {
+
+	jobs := uint64(1)
+	var err error
+	if *flagJobs == 0 {
+		jobs = 0
+	} else if *flagJobs > 0 {
+		jobs = uint64(*flagJobs)
+	} else if v := os.Getenv(EnvJobs); v != "" {
+		jobs, err = strconv.ParseUint(v, 10, 64)
+		if err != nil {
+			log.Fatalln("can not parse", EnvJobs, err)
+		}
+	}
+	if jobs == 0 {
 		// infinite jobs
 		return
 	}
-	var err error
+
 	JSR, JSW, err = os.Pipe()
 	if err != nil {
-		panic(err)
+		log.Fatalln(err)
 	}
-	for i := uint(0); i < *JobsN; i++ {
-		jsRelease()
+	for i := uint64(0); i < jobs; i++ {
+		jsRelease("initial fill")
 	}
 }
 
-func jsRelease() {
-	if JSW == nil {
-		return
-	}
-	trace(CJS, "release")
+func jsReleaseNoLock() {
 	if n, err := JSW.Write([]byte{0}); err != nil || n != 1 {
-		panic("can not write JSW")
+		log.Fatalln("can not write JSW:", err)
+	}
+}
+
+func jsRelease(ctx string) int {
+	if JSW == nil {
+		return 0
 	}
+	trace(CJS, "release from %s", ctx)
+	jsTokensM.Lock()
+	jsTokens--
+	left := jsTokens
+	jsReleaseNoLock()
+	jsTokensM.Unlock()
+	return left
 }
 
-func jsAcquire() {
+func jsAcquire(ctx string) {
 	if JSR == nil {
 		return
 	}
-	trace(CJS, "acquire")
+	trace(CJS, "acquire for %s", ctx)
 	if n, err := JSR.Read([]byte{0}); err != nil || n != 1 {
-		panic("can not read JSR")
+		log.Fatalln("can not read JSR:", err)
 	}
+	jsTokensM.Lock()
+	jsTokens++
+	jsTokensM.Unlock()
+	trace(CJS, "acquired for %s", ctx)
 }