From 4cc08a580ddcdc025d2ca23c336e76c11414d8e0 Mon Sep 17 00:00:00 2001
From: Mikko Rasa <tdb@tdb.fi>
Date: Thu, 6 Sep 2012 16:30:25 +0300
Subject: [PATCH] Add a side effect system for building multiple targets at
 once

---
 source/filetarget.cpp | 10 ++++++++++
 source/target.cpp     | 20 +++++++++++++++++++-
 source/target.h       | 12 ++++++++++++
 3 files changed, 41 insertions(+), 1 deletion(-)

diff --git a/source/filetarget.cpp b/source/filetarget.cpp
index ec89be8..af63c23 100644
--- a/source/filetarget.cpp
+++ b/source/filetarget.cpp
@@ -87,6 +87,16 @@ void FileTarget::check_rebuild()
 		}
 	}
 
+	if(!needs_rebuild())
+	{
+		for(Dependencies::iterator i=side_effects.begin(); (i!=side_effects.end() && !needs_rebuild()); ++i)
+		{
+			FileTarget *ft = dynamic_cast<FileTarget *>(*i);
+			if(ft && !ft->get_mtime())
+				mark_rebuild((*i)->get_name()+" does not exist");
+		}
+	}
+
 	if(!needs_rebuild() && package)
 	{
 		if(package->get_config().get_mtime()>mtime)
diff --git a/source/target.cpp b/source/target.cpp
index 64e1115..352b788 100644
--- a/source/target.cpp
+++ b/source/target.cpp
@@ -17,7 +17,8 @@ Target::Target(Builder &b, const string &n):
 	component(0),
 	name(n),
 	tool(0),
-	state(INIT)
+	state(INIT),
+	primary_target(0)
 {
 	builder.add_target(this);
 }
@@ -31,8 +32,19 @@ void Target::add_dependency(Target &dep)
 		dep.signal_bubble_rebuild.connect(sigc::mem_fun(this, &Target::check_rebuild));
 }
 
+void Target::add_side_effect(Target &se)
+{
+	side_effects.push_back(&se);
+	se.add_dependency(*this);
+	if(tool)
+		se.set_tool(*tool);
+	se.primary_target = this;
+}
+
 Target *Target::get_buildable_target()
 {
+	if(primary_target)
+		return primary_target->get_buildable_target();
 	if(!needs_rebuild())
 		return 0;
 
@@ -55,6 +67,8 @@ Target *Target::get_buildable_target()
 void Target::set_tool(const Tool &t)
 {
 	tool = &t;
+	for(Dependencies::const_iterator i=side_effects.begin(); i!=side_effects.end(); ++i)
+		(*i)->set_tool(t);
 }
 
 void Target::force_rebuild()
@@ -126,5 +140,9 @@ void Target::build_finished(bool success)
 {
 	state = UPTODATE;
 	if(success)
+	{
 		modified();
+		for(Dependencies::const_iterator i=side_effects.begin(); i!=side_effects.end(); ++i)
+			(*i)->build_finished(success);
+	}
 }
diff --git a/source/target.h b/source/target.h
index 48b3424..0b9d230 100644
--- a/source/target.h
+++ b/source/target.h
@@ -47,6 +47,8 @@ protected:
 	std::string rebuild_reason;
 
 	Dependencies depends;
+	Dependencies side_effects;
+	Target *primary_target;
 
 	Target(Builder &, const std::string &);
 public:
@@ -62,6 +64,10 @@ public:
 	this won't be detected until the targets are prepared. */
 	void add_dependency(Target &);
 
+	/** Adds a side effect for the target.  Side effects are not built on their
+	own, but together with their primary target. */
+	void add_side_effect(Target &);
+
 protected:
 	/** Finds dependencies for the target.  Called during preparation.  If the
 	target needs to recursively inspect its dependencies, it should prepare its
@@ -72,6 +78,12 @@ public:
 	/// Returns the dependencies of the target, in the order they were added.
 	const Dependencies &get_dependencies() const { return depends; }
 
+	/// Returns the side effects of the target.
+	const Dependencies &get_side_effects() const { return side_effects; }
+
+	/// Returns the primary target associated with a side effect target.
+	Target *get_primary_target() const { return primary_target; }
+
 	/** Tries to locate a target that will help getting this target built.  If
 	all dependencies are up-to-date, returns this target.  If there are no
 	targets ready to be built (maybe because they are being built right now),
-- 
2.43.0