read_file has some limitations:
- It is not possible to check the error code since read_file returns
NULL for failure
- It is not possible to limit the buffer size to sensible limits.
This patch introduces read_file_2 which doesn't have these limitations.
read_file becomes a wrapper around read_file_2.
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
We have our file helper functions in several places. Move them
all to lib/libfile.c.
With this we no longer have file helpers in fs/fs.c which contains
the core fs functions and no functions in lib/libbb.c which are
not from busybox.
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
