From: jingui.ren <jingui.ren@samsung.com>
Date: Fri, 26 Oct 2018 05:41:27 +0000 (+0800)
Subject: optimize the algorithm of get_top_order
X-Git-Tag: submit/devel/20190730.074511~2^2~2
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=2f7e94f7d17ee115192f12b3fc7a88641926f737;p=tools%2Fdepanneur.git

optimize the algorithm of get_top_order

Change-Id: I310e9425beb75bae53f72218d96ef42be5def21d
---

diff --git a/depanneur b/depanneur
index d77ecb6..2b08728 100755
--- a/depanneur
+++ b/depanneur
@@ -1398,92 +1398,36 @@ sub check_circle {
 }
 
 #---------------------------------------------------------------------
-#Get one package's dependence
-#Eg: A->B->C->(D H)
-#if we get_ddeps_list(A) ,will get @{D H C B}
-#---------------------------------------------------------------------
-sub get_ddeps_list {
-     my $pack = shift;
-     my @list = ();
-
-     if (! defined($pkgddeps{$pack}) ||
-	scalar $pkgddeps{$pack} == 0
-     ) {
-	return @list;
-     }
-
-     for my $name  (@{ $pkgddeps{$pack} }) {
-		push @list, get_ddeps_list($name);
-		push @list, $name;
-     }
-
-     return @list;
-}
-
-#---------------------------------------------------------------------
-# generate topological sort sequence from global %pkgddeps
+# according to BFS to solve topological sorting issue
 #---------------------------------------------------------------------
 sub get_top_order {
-    my @top_order = ();
-    my %ref = ();
-    my $max = 0;
-
-    for my $pack (sort keys %pkgddeps) {
-        $ref{$pack} = 0;
-    }
-
-    for my $pack (sort keys %pkgddeps) {
-        next if (! defined($pkgddeps{$pack}));
-        for (@{$pkgddeps{$pack} }) {
-            $ref{$_} += 1;
+        my @queue = ();
+        my @top_order = ();
+        my %ref_build_complete = ();
+        for my $pack (sort keys %pkgddeps) {
+                $ref_build_complete{$pack} = 0;
+                my $pack_in_degree = 0;
+                if (defined $pkgddeps{$pack}) {
+                    $pack_in_degree = @{$pkgddeps{$pack}};
+                }
+                if ($pack_in_degree == 0) {
+                        push @queue, $pack;
+                }
         }
-    }
-
-    for my $pkg (sort keys %ref) {
-	if ($max < ($ref{$pkg})) {
-		$max = ($ref{$pkg});
-	}
-    }
-
-    while (@top_order != scalar (keys %pkgddeps)) {
-
-        for my $pkg (sort keys %ref) {
-            if ($ref{$pkg} == $max) {
-                push @top_order, $pkg;
-                delete $ref{$pkg};
-            } else {
-		$ref{$pkg} += 1;
-	    }
-        }
-    }
-
-    my @final_order = ();
-    for my $name (@top_order) {
-	next if (! defined($pkgddeps{$name}));
-	next if ( grep $_ eq $name,  @final_order) ;
-	my @cnt = @{$pkgddeps{$name} };
-	if (scalar(@cnt) == 0) {
-		push @final_order, $name;
-	} else {
-		for my $list_pk (@cnt){
-			next if ( grep $_ eq $list_pk,  @final_order);
-
-			my @tmp_order = get_ddeps_list($list_pk);
-			for my $pk (@tmp_order) {
-				if (! grep $_ eq $pk,  @final_order) {
-					push @final_order, $pk;
-				}
-			}
-			push @final_order, $list_pk;
-		}
-		push @final_order, $name;
-	}
-    }
-
-     return @final_order;
+        while(@queue) {
+                my $cur_pack = shift @queue;
+                push @top_order, $cur_pack;
+                #print "write $cur_pack\n";
+                for (@{$pkgrddeps{$cur_pack}}) {
+                        $ref_build_complete{$_} += 1;
+                        if (@{$pkgddeps{$_}} == $ref_build_complete{$_}) {
+                                push @queue, $_;
+                        }
+                }
+        }
+        return @top_order;
 }
 
-
 #---------------------------------------------------------------------
 # update dependencies of every packages not build yet
 #---------------------------------------------------------------------
@@ -1574,7 +1518,7 @@ sub update_pkgddeps {
     my @top_order = get_top_order();
     if ($get_order == 0) {
     	@build_order = @top_order;
-	$get_order = 1;
+		$get_order = 1;
     }
 
     %pkgdeps = ();