/*
-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
package main
-import "os"
+import (
+ "flag"
+ "fmt"
+ "log"
+ "os"
+ "regexp"
+ "strconv"
+ "sync"
+)
+
+const (
+ EnvMakeFlags = "MAKEFLAGS"
+
+ EnvJSFd = "REDO_JS_FD"
+ EnvJobs = "REDO_JOBS"
+ EnvJSToken = "REDO_JS_TOKEN"
+ EnvMake = "REDO_MAKE"
+
+ MakeTypeNone = "none"
+ MakeTypeBmake = "bmake"
+ MakeTypeGmake = "gmake"
+)
var (
+ // bmake (NetBSD make)
+ BMakeGoodToken = byte('+')
+ BMakeJSArg = "-j 1 -J "
+ BMakeJSArgRe = regexp.MustCompile(`(.*)\s*-J (\d+),(\d+)\s*(.*)`)
+
+ // GNU Make
+ GMakeJSArg = "--jobserver-auth="
+ GMakeJSArgRe = regexp.MustCompile(`(.*)\s*--jobserver-auth=(\d+),(\d+)\s*(.*)`)
+
+ // dummy make
+ DMakeJSArg = ""
+ DMakeJSArgRe = regexp.MustCompile(`(.*)\s*(\d+),(\d+)\s*(.*)`)
+
+ MakeFlagsName = EnvMakeFlags
+ MakeFlags string
+ MakeJSArg string
+
JSR *os.File
JSW *os.File
+
+ jsToken byte // got via EnvJSToken
+ jsTokens map[byte]int
+ jsTokensM sync.Mutex
+
+ flagJobs *int
)
-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" {
- // infinite jobs
+func init() {
+ cmdName := CmdName()
+ if !(cmdName == CmdNameRedo || cmdName == CmdNameRedoIfchange) {
return
}
- if jsrRaw != "" {
- JSR = mustParseFd(jsrRaw, "JSR")
- JSW = mustParseFd(jswRaw, "JSW")
- jsRelease("ifchange entered")
- return
+ flagJobs = flag.Int("j", -1,
+ fmt.Sprintf("number of parallel jobs (0=inf, <0=1) (%s)", EnvJobs))
+}
+
+func jsStart(jobsEnv string) {
+ jobs := uint64(1)
+ var err error
+ if *flagJobs == 0 {
+ jobs = 0
+ } else if *flagJobs > 0 {
+ jobs = uint64(*flagJobs)
+ } else if jobsEnv != "" {
+ jobs, err = strconv.ParseUint(jobsEnv, 10, 64)
+ if err != nil {
+ log.Fatalln("can not parse", EnvJobs, err)
+ }
}
- if *JobsN == 0 {
+ 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("initial fill")
+ trace(CJS, "initial fill with %d", jobs)
+ jsTokens[BMakeGoodToken] = int(jobs)
+ for ; jobs > 0; jobs-- {
+ jsReleaseNoLock(BMakeGoodToken)
}
}
-func jsRelease(ctx string) {
+func jsInit() {
+ jsTokens = make(map[byte]int)
+
+ makeType := os.Getenv(EnvMake)
+ var makeArgRe *regexp.Regexp
+ switch makeType {
+ case MakeTypeGmake:
+ makeArgRe = GMakeJSArgRe
+ MakeJSArg = GMakeJSArg
+ case MakeTypeBmake:
+ makeArgRe = BMakeJSArgRe
+ MakeJSArg = BMakeJSArg
+ case "":
+ fallthrough
+ case MakeTypeNone:
+ MakeFlagsName = EnvJSFd
+ makeArgRe = DMakeJSArgRe
+ MakeJSArg = DMakeJSArg
+ default:
+ log.Fatalln("unknown", EnvMake, "type")
+ }
+
+ MakeFlags = os.Getenv(MakeFlagsName)
+ jobsEnv := os.Getenv(EnvJobs)
+ if jobsEnv == "NO" {
+ // jobserver disabled, infinite jobs
+ return
+ }
+ if MakeFlags == "" {
+ // we are not running under make
+ jsStart(jobsEnv)
+ return
+ }
+
+ match := makeArgRe.FindStringSubmatch(MakeFlags)
+ if len(match) == 0 {
+ // MAKEFLAGS does not contain anything related to jobserver
+ jsStart(jobsEnv)
+ return
+ }
+ MakeFlags = match[1] + " " + match[4]
+
+ func() {
+ defer func() {
+ if err := recover(); err != nil {
+ log.Fatalln(err)
+ }
+ }()
+ JSR = mustParseFd(match[2], "JSR")
+ JSW = mustParseFd(match[3], "JSW")
+ }()
+
+ if token := os.Getenv(EnvJSToken); token != "" {
+ jsTokenInt, err := strconv.ParseUint(token, 10, 8)
+ if err != nil {
+ log.Fatalln("invalid", EnvJSToken, "format:", err)
+ }
+ jsToken = byte(jsTokenInt)
+ jsTokens[jsToken]++
+ jsRelease("ifchange entered", jsToken)
+ }
+}
+
+func jsReleaseNoLock(token byte) {
+ if n, err := JSW.Write([]byte{token}); err != nil || n != 1 {
+ log.Fatalln("can not write JSW:", err)
+ }
+}
+
+func jsRelease(ctx string, token byte) {
if JSW == nil {
return
}
trace(CJS, "release from %s", ctx)
- if n, err := JSW.Write([]byte{0}); err != nil || n != 1 {
- panic("can not write JSW")
+ jsTokensM.Lock()
+ jsTokens[token]--
+ jsReleaseNoLock(token)
+ jsTokensM.Unlock()
+}
+
+func jsReleaseAll() {
+ jsTokensM.Lock()
+ for token, i := range jsTokens {
+ for ; i > 0; i-- {
+ jsReleaseNoLock(token)
+ }
}
+ jsTokensM.Unlock()
}
-func jsAcquire(ctx string) {
+func jsAcquire(ctx string) byte {
if JSR == nil {
- return
+ return BMakeGoodToken
}
trace(CJS, "acquire for %s", ctx)
- if n, err := JSR.Read([]byte{0}); err != nil || n != 1 {
- panic("can not read JSR")
+ token := []byte{0}
+ if n, err := JSR.Read(token); err != nil || n != 1 {
+ log.Fatalln("can not read JSR:", err)
}
+ jsTokensM.Lock()
+ jsTokens[token[0]]++
+ jsTokensM.Unlock()
trace(CJS, "acquired for %s", ctx)
+ return token[0]
}