server: kill stdin/stdout/stderr

This ensures that nothing run from the server can touch the console, in
particular event handlers and python tasks, both of which can use bb.msg or
the bitbake loggers to send output to the UI in a correct fashion instead.

Signed-off-by: Chris Larson <chris_larson@mentor.com>

1 files changed, 15 insertions, 0 deletions

diff --git a/lib/bb/utils.py b/lib/bb/utils.py
index 48b120ce5..ea5af49cd 100644
--- a/lib/bb/utils.py
+++ b/lib/bb/utils.py
@@ -774,3 +774,18 @@ def init_logger(logger, verbose, debug, debug_domains):
 
     if debug_domains:
         bb.msg.set_debug_domains(debug_domains)
+
+@contextmanager
+def redirected_fds(from_files, to_files):
+    assert len(from_files) == len(to_files), 'from_files / to_files length mismatch'
+
+    old_fds = []
+    for position, fobj in enumerate(from_files):
+        fd = fobj.fileno()
+        old_fds.append(os.dup(fd))
+        os.dup2(to_files[position].fileno(), fd)
+
+    yield
+
+    for position, fd in enumerate(old_fds):
+        os.dup2(fd, from_files[position].fileno())