When using a pty for logging, use setsid() to create a new session and make the pty into the controlling terminal of the new session. This makes interactive ebuild behave properly in interactive cases like check_license() where ${PAGER:-less} is invoked.

svn path=/main/trunk/; revision=6747

3 files changed, 72 insertions, 11 deletions

diff --git a/pym/portage/__init__.py b/pym/portage/__init__.py
index c931ed32a..b6fbf2cad 100644
--- a/pym/portage/__init__.py
+++ b/pym/portage/__init__.py
@@ -2290,6 +2290,8 @@ def spawn(mystring, mysettings, debug=0, free=0, droppriv=0, sesandbox=0, **keyw
 	slave_fd = None
 	output_pid = None
 	input_pid = None
+	stdin_termios = None
+	stdin_fd = None
 	if logfile:
 		del keywords["logfile"]
 		fd_pipes = keywords.get("fd_pipes")
@@ -2299,12 +2301,41 @@ def spawn(mystring, mysettings, debug=0, free=0, droppriv=0, sesandbox=0, **keyw
 			raise ValueError(fd_pipes)
 		from pty import openpty
 		master_fd, slave_fd = openpty()
-		# Disable the ECHO attribute so the terminal behaves properly
-		# if the subprocess needs to read input from stdin.
-		import termios
-		term_attr = termios.tcgetattr(slave_fd)
-		term_attr[3] &= ~termios.ECHO
-		termios.tcsetattr(slave_fd, termios.TCSAFLUSH, term_attr)
+		fd_pipes.setdefault(0, sys.stdin.fileno())
+		stdin_fd = fd_pipes[0]
+		if os.isatty(stdin_fd):
+			# Copy the termios attributes from stdin_fd to the slave_fd and put
+			# the stdin_fd into raw mode with ECHO disabled.  The stdin
+			# termios attributes are reverted before returning, or via the
+			# atexit hook in portage.process when killed by a signal.
+			import termios, tty
+			stdin_termios = termios.tcgetattr(stdin_fd)
+			tty.setraw(stdin_fd)
+			term_attr = termios.tcgetattr(stdin_fd)
+			term_attr[3] &= ~termios.ECHO
+			termios.tcsetattr(stdin_fd, termios.TCSAFLUSH, term_attr)
+			termios.tcsetattr(slave_fd, termios.TCSAFLUSH, stdin_termios)
+			from output import get_term_size, set_term_size
+			rows, columns = get_term_size()
+			set_term_size(rows, columns, slave_fd)
+			pre_exec = keywords.get("pre_exec")
+			def setup_ctty():
+				os.setsid()
+				# Make it into the "controlling terminal".
+				import termios
+				if hasattr(termios, "TIOCSCTTY"):
+					# BSD 4.3 approach
+					import fcntl
+					fcntl.ioctl(0, termios.TIOCSCTTY)
+				else:
+					# SVR4 approach
+					fd = os.open(os.ttyname(0), os.O_RDWR)
+					for x in 0, 1, 2:
+						os.dup2(fd, x)
+					os.close(fd)
+				if pre_exec:
+					pre_exec()
+			keywords["pre_exec"] = setup_ctty
 		# tee will always exit with an IO error, so ignore it's stderr.
 		null_file = open('/dev/null', 'w')
 		mypids.extend(portage.process.spawn(['tee', '-i', '-a', logfile],
@@ -2374,8 +2405,12 @@ def spawn(mystring, mysettings, debug=0, free=0, droppriv=0, sesandbox=0, **keyw
 		os.waitpid(input_pid, 0)
 		portage.process.spawned_pids.remove(input_pid)
 	pid = mypids[-1]
-	retval = os.waitpid(pid, 0)[1]
-	portage.process.spawned_pids.remove(pid)
+	try:
+		retval = os.waitpid(pid, 0)[1]
+		portage.process.spawned_pids.remove(pid)
+	finally:
+		if stdin_termios:
+			termios.tcsetattr(stdin_fd, termios.TCSAFLUSH, stdin_termios)
 	if retval != os.EX_OK:
 		if retval & 0xff:
 			return (retval & 0xff) << 8
diff --git a/pym/portage/output.py b/pym/portage/output.py
index f5e261c82..b4877b30d 100644
--- a/pym/portage/output.py
+++ b/pym/portage/output.py
@@ -260,6 +260,15 @@ def get_term_size():
 				pass
 	return -1, -1
 
+def set_term_size(lines, columns, fd):
+	"""
+	Set the number of lines and columns for the tty that is connected to fd.
+	For portability, this simply calls `stty rows $lines columns $columns`.
+	"""
+	from portage.process import spawn
+	cmd = ["stty", "rows", str(lines), "columns", str(columns)]
+	spawn(cmd, env=os.environ, fd_pipes={0:fd})
+
 class EOutput:
 	"""
 	Performs fancy terminal formatting for status and informational messages.
diff --git a/pym/portage/process.py b/pym/portage/process.py
index dfc106e6b..0cb175375 100644
--- a/pym/portage/process.py
+++ b/pym/portage/process.py
@@ -111,9 +111,19 @@ def cleanup():
 
 atexit_register(cleanup)
 
+# Make sure the original terminal attributes are reverted at exit.
+if sys.stdin.isatty():
+	import termios
+	_stdin_termios = termios.tcgetattr(sys.stdin.fileno())
+	def _reset_stdin_termios(stdin_termios):
+		import termios
+		termios.tcsetattr(sys.stdin.fileno(), termios.TCSAFLUSH, stdin_termios)
+	atexit_register(_reset_stdin_termios, _stdin_termios)
+	del termios, _stdin_termios, _reset_stdin_termios
+
 def spawn(mycommand, env={}, opt_name=None, fd_pipes=None, returnpid=False,
           uid=None, gid=None, groups=None, umask=None, logfile=None,
-          path_lookup=True):
+          path_lookup=True, pre_exec=None):
 	"""
 	Spawns a given command.
 	
@@ -140,6 +150,8 @@ def spawn(mycommand, env={}, opt_name=None, fd_pipes=None, returnpid=False,
 	@type logfile: String
 	@param path_lookup: If the binary is not fully specified then look for it in PATH
 	@type path_lookup: Boolean
+	@param pre_exec: A function to be called with no arguments just prior to the exec call.
+	@type pre_exec: callable
 	
 	logfile requires stdout and stderr to be assigned to this process (ie not pointed
 	   somewhere else.)
@@ -194,7 +206,7 @@ def spawn(mycommand, env={}, opt_name=None, fd_pipes=None, returnpid=False,
 	if not pid:
 		try:
 			_exec(binary, mycommand, opt_name, fd_pipes,
-			      env, gid, groups, uid, umask)
+			      env, gid, groups, uid, umask, pre_exec)
 		except Exception, e:
 			# We need to catch _any_ exception so that it doesn't
 			# propogate out of this function and cause exiting
@@ -251,7 +263,8 @@ def spawn(mycommand, env={}, opt_name=None, fd_pipes=None, returnpid=False,
 	# Everything succeeded
 	return 0
 
-def _exec(binary, mycommand, opt_name, fd_pipes, env, gid, groups, uid, umask):
+def _exec(binary, mycommand, opt_name, fd_pipes, env, gid, groups, uid, umask,
+	pre_exec):
 
 	"""
 	Execute a given binary with options
@@ -274,6 +287,8 @@ def _exec(binary, mycommand, opt_name, fd_pipes, env, gid, groups, uid, umask):
 	@type uid: Integer
 	@param umask: an int representing a unix umask (see man chmod for umask details)
 	@type umask: Integer
+	@param pre_exec: A function to be called with no arguments just prior to the exec call.
+	@type pre_exec: callable
 	@rtype: None
 	@returns: Never returns (calls os.execve)
 	"""
@@ -315,6 +330,8 @@ def _exec(binary, mycommand, opt_name, fd_pipes, env, gid, groups, uid, umask):
 		os.setuid(uid)
 	if umask:
 		os.umask(umask)
+	if pre_exec:
+		pre_exec()
 
 	# And switch to the new process.
 	os.execve(binary, myargs, env)