[LEDE-DEV] [PATCH 0/5] procd: stdio handling rework

[Jo-Philipp Wich]

Currently the vi editor will fail with "vi: can't read user input" in failsafe
mode because procd patches all stdio channels to the same descriptor, then sets
nonblocking mode on stderr which causes stdin to end up in nonblocking mode as
well.

Programs like "vi" expect read operations on stdin to block when no input is
available, causing them to fail if read() unexpectedly yields EAGAIN errors.

This patch series addresses the problem by introducing common utility functions
to deal with stdio redirections. The implementation will assign a distinct
descriptor to each i/o channel and use the proper mode (O_WRONLY/O_RDONLY)
when setting them up.

Call sites touching stdin, stdout and stderr are converted to the common
utility functions and error logging is added where appropriate.

While we're at it we also fix a file descriptor leak caused by a missing
close() after a creat() call in preinit.c

Jo-Philipp Wich (5):
  utils: add patch_fd() and patch_stdio() helpers
  initd: use patch_stdio() for early console setup
  initd: use patch_stdio() for kmodloader stdio redirection
  inittab: use patch_stdio() for stdio redirection
  initd: fix descriptor leak

 initd/early.c   | 18 +++++-------------
 initd/init.c    | 14 +++-----------
 initd/preinit.c |  9 ++++++++-
 inittab.c       | 12 ++----------
 utils/utils.c   | 54 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 utils/utils.h   |  3 +++
 6 files changed, 75 insertions(+), 35 deletions(-)

-- 
2.1.4