tree 820ec0adc378f3fe3cd53d7be6cbc1f04f285ef4
parent ef52ae14abaf091b1bece89656d80850b497e084
author Yongqin Liu <yongqin.liu@linaro.org> 1482912379 +0800
committer Wei Wang <wvw@google.com> 1492620579 +0000

init: use read_file and write_file to implement do_copy builtin

this will make the implementation more cleaner,
and has error message output when failed on some operations

also add the O_TRUNC flag explicitly for the open function
called in write_file.

And add more test on read_file and write_file functions

Bug: 36726045
Bug: 36576280
Test: manual with hikey
Test: boot and init tests on bullhead
Test: cast with fugu, per b/36726045
Merged-In: If3c30a2fff58cfece2fcd27e69c30382146e6808

Change-Id: If3c30a2fff58cfece2fcd27e69c30382146e6808
Signed-off-by: Yongqin Liu <yongqin.liu@linaro.org>
(cherry picked from commit dbe88e7953ed53961056c7f5531d91d229293462)