Revamp the build system.

Quick summary of changes:

  - Move list of cairo source files out of src/Makefile.am and into
    src/Sources.mk,

  - Generate files src/Config.mk and src/Config.mk.win32 that choose
    the right set of source files and headers based on configured
    backends and features.  This drastically simplifies building
    using other build systems.  The src/Makefile.win32 file needs
    to be updated to reflect these changes.

  - Add README files to various directories,

  - Add toplevel HACKING file.

1 files changed, 58 insertions, 0 deletions

diff --git a/src/README b/src/README
new file mode 100644
index 00000000..f29dd3ac
--- /dev/null
+++ b/src/README
@@ -0,0 +1,58 @@
+Cairo Library Source Code
+=========================
+
+This directory contains the source code to the cairo library.
+
+
+Source Code Listing
+-------------------
+
+The canonical list of source files is the file Source.mk.  See that
+file for how it works.
+
+
+New Backends
+------------
+
+The rule of the thumb for adding new backends is to see how other
+backends are integrated.  Pick one of the simpler, unsupported, backends
+and search the entire tree for it, and go from there.
+
+To add new backends you need to basically:
+
+  * Modify $(top_srcdir)/configure.in to add checks for your backend.
+
+  * Modify Sources.mk to add source files for your backend,
+
+  * Modify $(top_srcdir)/boilerplate/ to add boilerplate code for
+    testing your new backend.
+
+
+New API
+-------
+
+After adding new API, run "make check" in this directory and fix any
+reported issues.  Also add new API to the right location in
+$(top_srcdir)/doc/public/cairo-sections.txt and run "make check"
+in $(top_builddir)/doc/public to make sure that any newly added
+documentation is correctly hooked up.
+
+Do not forget to add tests for the new API.  See next section.
+
+
+Tests
+-----
+
+There are some tests in this directory that check the source code and
+the build for various issues.  The tests are very quick to run, and
+particularly should be run after any documentation or API changes.  It
+does not hurt to run them after any source modification either.  Run
+them simply by calling:
+
+	make check
+
+There are also extensive regression tests in $(top_srcdir)/test.  It is
+a good idea to run that test suite for any changes made to the source
+code.  Moreover, for any new feature, API, or bug fix, new tests should
+be added to the regression test suite to test the new code.
+