Saved the threading plan from the branch.

This was the only useful thing in the threading breanch.

1 files changed, 28 insertions, 0 deletions

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+It looks like the following changes will have to happen in order to allow build
+to bu truly multi-threaded.  We can't proceed like I originally thought, the
+entire system is build-script driven, including the profiles that do the actual
+building.
+
+1. Context needs to be broken apart into everything it currently has except
+   the ScopeStack, and the ScopeStack.  The initial ScopeStack (the root level)
+   will be built before the program goes multi-thraeded, then it will be copied
+   into each thread so they all start with the same global state.
+   Targets will still be built the same way, so we won't have to worry about
+   targets' global variable overrides.
+2. Instead of each target actually processing it's complete list of dependancies
+   when it's processed, it should create a queue of them.  This may well be the
+   biggest change, but it still should be fairly doable.  We'll still process
+   them in the same order, which will make things pretty easy.
+   That queue will be global, and will be what feeds the thread dispatcher.
+3. A new thread handler and thread class needs to be created.  The threads will
+   dequeue targets from the target queue and process them provided all
+   prerequisites have been completed.  We can do this a few ways, but I think
+   a simple loop will suffice.
+   Loop steps:
+     1. Check all deps on target, if completed, then execute, otherwise:
+         2. Wait on condition that is triggered every time a target is completed.
+         3. Go back to 1
+4. View needs to be made completely thread-safe, I'm thinking maybe through a
+   View system middle layer handler in order to keep the specific View code
+   pretty simple.
+