u-boot/arch/sandbox
Rasmus Villemoes 2960107a22 sandbox: also restore terminal settings when killed by SIGINT
Hitting Ctrl-C is a documented way to exit the sandbox, but it is not
actually equivalent to the reset command. The latter, since it follows
normal process exit, takes care to reset terminal settings and
restoring the O_NONBLOCK behaviour of stdin (and, in a terminal, that
is usually the same file description as stdout and stderr, i.e. some
/dev/pts/NN).

Failure to restore (remove) O_NONBLOCK from stdout/stderr can cause
very surprising and hard to debug problems back in the terminal. For
example, I had "make -j8" consistently failing without much
information about just exactly what went wrong, but sometimes I did
get a "echo: write error". I was at first afraid my disk was getting
bad, but then a simple "dmesg" _also_ failed with write error - so it
was writing to the terminal that was buggered. And both "make -j8" and
dmesg in another terminal window worked just fine.

So install a SIGINT handler so that if the chosen terminal
mode (cooked or raw-with-sigs) means Ctrl-C sends a SIGINT, we will
still call os_fd_restore(), then reraise the signal and die as usual
from SIGINT.

Before:

$ grep flags /proc/$$/fdinfo/1
flags:  0102002
$ ./u-boot
# hit Ctrl-C
$ grep flags /proc/$$/fdinfo/1
flags:  0106002

After:

$ grep flags /proc/$$/fdinfo/1
flags:  0102002
$ ./u-boot
# hit Ctrl-C
$ grep flags /proc/$$/fdinfo/1
flags:  0102002

Signed-off-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
Reviewed-by: Simon Glass <sjg@chromium.org>
2020-04-16 08:07:57 -06:00
..
cpu sandbox: also restore terminal settings when killed by SIGINT 2020-04-16 08:07:57 -06:00
dts sandbox: Update PCI nodes in dts files 2020-04-16 08:07:57 -06:00
include/asm dma-mapping: add <asm/dma-mapping.h> for all architectures 2020-02-20 15:09:54 +08:00
lib common: Move interrupt functions into a new header 2019-12-02 18:25:00 -05:00
config.mk sandbox: sdl: Move to use SDL2 2020-02-05 19:33:46 -07:00
Kconfig sandbox: Add 64-bit sandbox 2018-02-18 15:53:48 -07:00
Makefile sandbox: Use 'extras' to specify 'head' files 2018-12-05 06:01:34 -07:00