Add locking to installed-chrome.txt updates. Bug #55174

config/add-chrome.pl

@@ -1,6 +1,11 @@
 #!/perl
 
 use File::Path;
+use Fcntl qw(:DEFAULT :flock);
+use Getopt::Std;
+use IO::File;
+
+getopts("l");
 
 my $installedChromeFile = $ARGV[0];
 my $disableJarPackaging = $ARGV[1];
@@ -10,6 +15,11 @@ my $jarFileName = $ARGV[4];
 
 #print "add-chrome $installedChromeFile $disableJarPackaging $chromeType $pkgName $jarFileName\n";
 
+my $nofilelocks = 0;
+if (defined($::opt_l)) {
+    $nofilelocks = 1;
+}
+
 if ($jarFileName =~ /(.*)\.jar/) {
     $jarFileName = $1;
 }
@@ -22,6 +32,15 @@ else {
     $line = "$chromeType,install,url,jar:resource:/chrome/$jarFileName.jar!/$chromeType/$pkgName/";
 }
 
+my $lockfile = "$installedChromeFile.lck";
+my $lockhandle = new IO::File;
+
+if (!$nofilelocks) {
+    open($lockhandle,">$lockfile") || 
+	die("WARNING: Could not create lockfile for $lockfile. Exiting.\n");
+    flock($lockhandle, LOCK_EX);
+}
+
 if (open(FILE, "<$installedChromeFile")) {
     while (<FILE>) {
         chomp;
@@ -29,6 +48,10 @@ if (open(FILE, "<$installedChromeFile")) {
             # line already appears in installed-chrome.txt file
             # just update the mod date
             close(FILE) || die "error: can't close $installedChromeFile: $!";
+	    if (!$nofilelocks) {
+		unlink($lockfile);
+		flock($lockhandle, LOCK_UN);
+	    }
             my $now = time;
             utime($now, $now, $installedChromeFile) || die "couldn't touch $installedChromeFile";
             print "+++ updating chrome $installedChromeFile\n+++\t$line\n";
@@ -37,6 +60,10 @@ if (open(FILE, "<$installedChromeFile")) {
     }
     close(FILE) || die "error: can't close $installedChromeFile: $!";
 }
+if (!$nofilelocks) {
+    unlink($lockfile);
+    flock($lockhandle, LOCK_UN);
+}
 
 my $dir = $installedChromeFile;
 if ("$dir" =~ /([\w\d.\-\\\/]+)[\\\/]([\w\d.\-]+)/) {
@@ -44,7 +71,17 @@ if ("$dir" =~ /([\w\d.\-\\\/]+)[\\\/]([\w\d.\-]+)/) {
 }
 mkpath($dir, 0, 0755);
 
+if (!$nofilelocks) {
+    open($lockhandle,">$lockfile") || 
+	die("WARNING: Could not create lockfile for $lockfile. Exiting.\n");
+    flock($lockhandle, LOCK_EX);
+}
 open(FILE, ">>$installedChromeFile") || die "can't open $installedChromeFile: $!";
 print FILE "$line\n";
 close(FILE) || die "error: can't close $installedChromeFile: $!";
+if (!$nofilelocks) {
+    unlink($lockfile);
+    flock($lockhandle, LOCK_UN);
+}
 print "+++ adding chrome $installedChromeFile\n+++\t$line\n";
+

config/rules.mak

@@ -599,18 +599,20 @@ _JAR_FLAT_FILES_ONLY=
 _JAR_REGCHROME_JAR=0
 !endif
 
-REGCHROME = @perl $(DEPTH)\config\add-chrome.pl $(DIST)\bin\chrome\installed-chrome.txt $(_JAR_REGCHROME_JAR)
+!if "$(OS_TARGET)" == "WIN95"
+_NO_FLOCK=-l
+!else
+_NO_FLOCK=
+!endif
+
+REGCHROME = @perl $(DEPTH)\config\add-chrome.pl $(_NO_FLOCK) $(DIST)\bin\chrome\installed-chrome.txt $(_JAR_REGCHROME_JAR)
 
 !ifndef MOZ_OLD_JAR_PACKAGING
 
 !if exist($(JAR_MANIFEST))
 
 chrome:: $(CHROME_DEPS)
-!if "$(OS_TARGET)"=="WIN95"
-        $(PERL) $(DEPTH)\config\make-jars.pl $(_JAR_FLAT_FILES_ONLY) -l -d $(DIST)\bin\chrome < $(JAR_MANIFEST)
-!else
-        $(PERL) $(DEPTH)\config\make-jars.pl $(_JAR_FLAT_FILES_ONLY) -d $(DIST)\bin\chrome < $(JAR_MANIFEST)
-!endif
+        $(PERL) $(DEPTH)\config\make-jars.pl $(_JAR_FLAT_FILES_ONLY) $(_NO_FLOCK) -d $(DIST)\bin\chrome < $(JAR_MANIFEST)
 !endif
 
 regchrome: