This adds a string buffer implementation + unit tests with
the following features:
- growing reallocation on append
- variadic printf-like append function
- indenting
- error state tracking (stop appending on errors)
This will be used in the GLSL shader construction to clean up
the bad string length issues we have now.
The variadic append is based on one Erik Faye-Lund wrote.
v1.1: improve indenting
v1.2: fix includes + use memcpy
Reviewed-by: Erik Faye-Lund <erik.faye-lund@collabora.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Dave Airlie