From 2404c0db7f32b5194d5a77c7a8040ad1dbf81a45 Mon Sep 17 00:00:00 2001 From: Thomas Petazzoni Date: Wed, 2 Jan 2013 07:08:48 +0000 Subject: [PATCH] graph-depends: remove redundant dependencies When doing a full graph of the dependencies, graph-depends starts by doing a "make show-targets", which lists all the packages registered in the $(TARGETS) variable. This variable contains all packages that are enabled according to the .config file. Then, for each of those packages, we used to create a "all" -> "package" dependency, even if in fact most of some packages are already dependencies of other packages. This creates a needlessly complex dependency graph. This patch modifies graph-depends so that it filters out the unneeded "all" -> "package" dependencies when "package" is already the dependency of another package. For example, if you have a configuration with libpng (which selects zlib), "make show-targets" displays "libpng zlib", so graph-depends used to create the following dependencies: (all -> libpng, all -> zlib, libpng -> zlib). However, the (all -> zlib) dependency is not really needed, as zlib is already the dependency of libpng. Those dependencies are now filtered out. Signed-off-by: Thomas Petazzoni Signed-off-by: Peter Korsgaard --- support/scripts/graph-depends | 33 +++++++++++++++++++++++++++++++++ 1 file changed, 33 insertions(+) diff --git a/support/scripts/graph-depends b/support/scripts/graph-depends index 409c123017..c80a65a17d 100755 --- a/support/scripts/graph-depends +++ b/support/scripts/graph-depends @@ -119,6 +119,37 @@ def get_all_depends(pkg): def pkg_node_name(pkg): return pkg.replace("-","") +# Helper function for remove_redundant_deps(). This function tells +# whether package "pkg" is the dependency of another package that is +# not the special "all" package. +def has_redundant_deps(deps, pkg): + for dep in deps: + if dep[0] != "all" and dep[1] == pkg: + return True + return False + +# This function removes redundant dependencies of the special "all" +# package. This "all" package is created to reflect the origin of the +# selection for all packages that are not themselves selected by any +# other package. So for example if you enable libpng, zlib is enabled +# as a dependency. But zlib being selected by libpng, it also appears +# as a dependency of the "all" package. This needlessly complicates +# the generated dependency graph. So when we have the dependency list +# (all -> zlib, all -> libpn, libpng -> zlib), we get rid of the 'all +# -> zlib' dependency, because zlib is already a dependency of a +# regular package. +def remove_redundant_deps(deps): + newdeps = [] + for dep in deps: + if dep[0] != "all": + newdeps.append(dep) + continue + if not has_redundant_deps(deps, dep[1]): + newdeps.append(dep) + continue + sys.stderr.write("Removing redundant dep all -> %s\n" % dep[1]) + return newdeps + # In full mode, start with the result of get_targets() to get the main # targets and then use get_all_depends() for each individual target. if mode == FULL_MODE: @@ -144,6 +175,8 @@ if mode == FULL_MODE: elif mode == PKG_MODE: dependencies = get_all_depends(rootpkg) +dependencies = remove_redundant_deps(dependencies) + # Start printing the graph data print "digraph G {" -- 2.30.2