--- a/build_package.pl	Wed May 06 18:26:34 2009 +0100
+++ b/build_package.pl	Fri May 22 16:52:18 2009 +0100
@@ -8,8 +8,11 @@
 my $sBOOTSTRAP_DIR="D:\\Helium\\hlm-apps\\bootstrap";
 my $sJOB_BASE_DIR="D:\\fbf_project";
 my $sCONFIG_REPO="\\\\lon-engbuild87\\d\$\\mercurial_development\\epl\\interim\\fbf\\configs\\pkgbuild\\FCL_pkgbuild";
+my $nMAX_JOBDIR_AGE_SECONDS = 86400; # max number of seconds after which the letter is forcibly released
 my $nLOCK_FILE_MAX_ATTEMPTS = 5;
 my $sNUMBERS_FILE="\\\\sym-build01\\f\$\\numbers.txt";
+my $sLETTERS_FILE="D:\\letters.txt";
+my $nMAX_LETTER_AGE_SECONDS = 86400; # max number of seconds after which the letter is forcibly released
 
 my $sProjectRepo = '';
 my $sJobLabel = '';
@@ -30,19 +33,44 @@
 print("hlm -f bootstrap.xml -Dsf.config.repo=$sCONFIG_REPO -Dsf.project.repo=$sProjectRepo -Dsf.target.dir=$sJobDir\n");
 system("hlm -f bootstrap.xml -Dsf.config.repo=$sCONFIG_REPO -Dsf.project.repo=$sProjectRepo -Dsf.target.dir=$sJobDir");
 
+# check that $sNUMBERS_FILE exists, otherwise create it
+if (!-f $sNUMBERS_FILE)
+{
+	open FILE, ">$sNUMBERS_FILE";
+	print FILE "\n";
+	close FILE;
+}
 
 my $nUnformattedNumber = ( $nCmdLineNumber ? $nCmdLineNumber : get_job_number($sProjectRepo));
 my $nJobNumber = sprintf("%.3d", $nUnformattedNumber);
 
+# check that $sLETTERS_FILE exists, otherwise create it
+if (!-f $sLETTERS_FILE)
+{
+	open FILE, ">$sLETTERS_FILE";
+	print FILE "\n";
+	close FILE;
+}
+
+# acquire drive letter
+my $sDriveLetter = acquire_drive_letter();
+print "acquired drive letter: $sDriveLetter\n";
+die "Could not acquire drive letter" if (! $sDriveLetter);
+
 print("cd $sJobDir\\sf-config\n");
 chdir("$sJobDir\\sf-config");
 print "###### BUILD PREPARATION ######\n";
-print("hlm sf-prep -Dsf.spec.job.number=$nJobNumber\n");
-system("hlm sf-prep -Dsf.spec.job.number=$nJobNumber");
+print("hlm sf-prep -Dsf.spec.job.number=$nJobNumber -Dsf.spec.job.drive=$sDriveLetter:\n");
+system("hlm sf-prep -Dsf.spec.job.number=$nJobNumber -Dsf.spec.job.drive=$sDriveLetter:");
 
 print "###### EXECUTE BUILD ######\n";
-print("hlm sf-build-all -Dsf.spec.job.number=$nJobNumber\n");
-system("hlm sf-build-all -Dsf.spec.job.number=$nJobNumber");
+print("hlm sf-build-all -Dsf.spec.job.number=$nJobNumber -Dsf.spec.job.drive=$sDriveLetter:\n");
+system("hlm sf-build-all -Dsf.spec.job.number=$nJobNumber -Dsf.spec.job.drive=$sDriveLetter:");
+
+# release the drive letter
+release_drive_letter($sDriveLetter);
+system("subst $sDriveLetter: /d"); # this is not required, but it's a good idea to keep things in order
+print "drive letter $sDriveLetter released (and drive unsubsted)\n";
 
 sub mkdir_unique
 {
@@ -67,6 +95,8 @@
 {
 	my ($sKey) = @_;
 	
+	$sKey=lc($sKey);
+	
 	my %hnNumbers = ();
 	
 	my $nAttempts = 0;
@@ -79,7 +109,7 @@
 			my $sLine;
 			while ($sLine = <FILE>)
 			{
-				$hnNumbers{$1} = $2 if ($sLine =~ m%(.*),(.*)%);
+				$hnNumbers{lc($1)} = $2 if ($sLine =~ m%(.*),(.*)%);
 			}
 			
 			$hnNumbers{$sKey} = 0 if (! $hnNumbers{$sKey} );
@@ -91,6 +121,7 @@
 			{
 				print FILE "$sStr,$hnNumbers{$sStr}\n";
 			}
+			truncate(FILE,tell(FILE));
 			
 			$bGotNumber = 1;
 		}
@@ -105,3 +136,114 @@
 	
 	return $hnNumbers{$sKey};
 }
+
+sub acquire_drive_letter
+{
+	my %hsPidsAndTimestamps = ();
+	
+	my $sLetterToRelease = '';
+	
+	my $nAttempts = 0;
+	my $bAcquired = 0;
+	do
+	{
+		open(FILE, "+<$sLETTERS_FILE") or die("Can't open $sLETTERS_FILE");
+		if ( flock(FILE, 6) )
+		{
+			my $sLine;
+			while ($sLine = <FILE>)
+			{
+				if ($sLine =~ m%([^,]*),(.*)%)
+				{
+					my $sLetter=$1;
+					my $sString=$2;
+					
+					$sString=~m%([^,]*),(.*)%;
+					my $nPid=$1;
+					my $nTimestamp=$2;
+					
+					if (time()-$nTimestamp<=$nMAX_LETTER_AGE_SECONDS)
+					{
+						$hsPidsAndTimestamps{$sLetter} = $sString;
+					}
+					else
+					{
+						# do nothing
+						print "forced release of letter: $sLetter\n";
+					}
+				}
+			}
+			
+			for my $sNewLetter ('H'..'Y')
+			{
+				if (! $hsPidsAndTimestamps{$sNewLetter})
+				{
+					my $sTimestamp = time();
+					$hsPidsAndTimestamps{$sNewLetter} = "$$,$sTimestamp";
+					$sLetterToRelease = $sNewLetter;
+					last;
+				}
+			}
+			
+			seek(FILE, 0, 0);
+
+			for my $sLetter ( keys(%hsPidsAndTimestamps) )
+			{
+				print FILE "$sLetter,$hsPidsAndTimestamps{$sLetter}\n";
+			}
+			truncate(FILE,tell(FILE));
+			
+			$bAcquired = 1;
+		}
+		else
+		{
+			$nAttempts ++;
+			sleep(3);
+		}
+		close(FILE);
+	}
+	until ( $bAcquired or $nAttempts == $nLOCK_FILE_MAX_ATTEMPTS );
+	
+	return $sLetterToRelease;
+}
+
+sub release_drive_letter
+{
+	my ($sLetterToRelease) = @_;
+	
+	my %hsPidsAndTimestamps = ();
+	
+	my $nAttempts = 0;
+	my $bAcquired = 0;
+	do
+	{
+		open(FILE, "+<$sLETTERS_FILE") or die("Can't open $sLETTERS_FILE");
+		if ( flock(FILE, 6) )
+		{
+			my $sLine;
+			while ($sLine = <FILE>)
+			{
+				$hsPidsAndTimestamps{$1} = $2 if ($sLine =~ m%([^,]*),(.*)%);
+			}
+			
+			delete $hsPidsAndTimestamps{$sLetterToRelease};
+			
+			seek(FILE, 0, 0);
+
+			for my $sLetter ( keys(%hsPidsAndTimestamps) )
+			{
+				print FILE "$sLetter,$hsPidsAndTimestamps{$sLetter}\n";
+			}
+			truncate(FILE,tell(FILE));
+			
+			$bAcquired = 1;
+		}
+		else
+		{
+			$nAttempts ++;
+			sleep(3);
+		}
+		close(FILE);
+	}
+	until ( $bAcquired or $nAttempts == $nLOCK_FILE_MAX_ATTEMPTS );
+}