From: Sergey Matveev <stargrave@stargrave.org>
Date: Sat, 23 Sep 2023 14:13:59 +0000 (+0300)
Subject: Prevent possible race when building target twice
X-Git-Tag: v1.31.0~2
X-Git-Url: http://www.git.cypherpunks.ru/?p=goredo.git;a=commitdiff_plain;h=8e1c9b41428b4c988a05644ca2e9f9c3b0a7d65e

Prevent possible race when building target twice
---

diff --git a/doc/news.texi b/doc/news.texi
index d519c7d..fcd0d75 100644
--- a/doc/news.texi
+++ b/doc/news.texi
@@ -2,6 +2,13 @@
 @cindex news
 @unnumbered News
 
+@anchor{Release 1_31_0}
+@section Release 1.31.0
+@itemize
+@item
+    Fixed possible race when target can be built more than once.
+@end itemize
+
 @anchor{Release 1_30_0}
 @section Release 1.30.0
 @itemize
diff --git a/ifchange.go b/ifchange.go
index 4a43872..401574d 100644
--- a/ifchange.go
+++ b/ifchange.go
@@ -109,7 +109,7 @@ func buildDependants(tgts []string) map[string]struct{} {
 	tracef(CDebug, "building %d alwayses: %v", len(seen), seen)
 	errs := make(chan error, len(seen))
 	for tgt := range seen {
-		if err := runScript(tgt, errs, false); err != nil {
+		if err := runScript(tgt, errs, false, false); err != nil {
 			tracef(CErr, "always run error: %s, skipping dependants", err)
 			return nil
 		}
@@ -155,7 +155,7 @@ RebuildDeps:
 		if !ood {
 			continue
 		}
-		if err := runScript(tgt, errs, false); err != nil {
+		if err := runScript(tgt, errs, false, false); err != nil {
 			tracef(CErr, "dependant error: %s, skipping dependants", err)
 			return nil
 		}
@@ -225,7 +225,7 @@ func ifchange(tgts []string, forced, traced bool) (bool, error) {
 			tracef(CDebug, "%s is source, not redoing", tgt)
 			continue
 		}
-		if err = runScript(tgt, errs, traced); err != nil {
+		if err = runScript(tgt, errs, forced, traced); err != nil {
 			return false, err
 		}
 		jobs++
diff --git a/main.go b/main.go
index 634ca8f..8c95d84 100644
--- a/main.go
+++ b/main.go
@@ -298,7 +298,7 @@ func main() {
 		}
 	}
 
-	if cmdName == CmdNameRedo || cmdName == CmdNameRedoIfchange {
+	if cmdName == CmdNameRedo {
 		statusInit()
 	}
 
diff --git a/run.go b/run.go
index 2e5dbf5..7ee4637 100644
--- a/run.go
+++ b/run.go
@@ -184,7 +184,7 @@ func syncDir(dir string) error {
 	return err
 }
 
-func runScript(tgtOrig string, errs chan error, traced bool) error {
+func runScript(tgtOrig string, errs chan error, forced, traced bool) error {
 	cwd, tgt := cwdAndTgt(tgtOrig)
 	redoDir := path.Join(cwd, RedoDir)
 	if err := mkdirs(redoDir); err != nil {
@@ -281,6 +281,19 @@ func runScript(tgtOrig string, errs chan error, traced bool) error {
 		return nil
 	}
 
+	// Check if it was already built in parallel
+	if !forced {
+		if fdDep, err := os.Open(path.Join(redoDir, tgt+DepSuffix)); err == nil {
+			depInfo, err := depRead(fdDep)
+			fdDep.Close()
+			if err == nil && depInfo.build == BuildUUID {
+				lockRelease()
+				errs <- nil
+				return nil
+			}
+		}
+	}
+
 	// Check if target is not modified externally
 	modified, inodePrev, hshPrev, err := isModified(cwd, redoDir, tgt)
 	if err != nil {
diff --git a/usage.go b/usage.go
index e67077f..6e43b57 100644
--- a/usage.go
+++ b/usage.go
@@ -24,7 +24,7 @@ import (
 )
 
 const (
-	Version  = "1.30.0"
+	Version  = "1.31.0"
 	Warranty = `Copyright (C) 2020-2023 Sergey Matveev
 
 This program is free software: you can redistribute it and/or modify