[FIX] real child process cannot be fetched from host, because it may died befor fetching it, so signal handling cannot be handled directly.

wexpect/console_reader.py

@@ -43,6 +43,7 @@ import os
 import traceback
 import pkg_resources 
 import psutil
+import signal
 from io import StringIO
 
 import ctypes
@@ -56,6 +57,7 @@ import socket
 
 from .wexpect_util import init_logger
 from .wexpect_util import EOF_CHAR
+from .wexpect_util import SIGNAL_CHARS
 
 # 
 # System-wide constants
@@ -109,6 +111,7 @@ class ConsoleReaderBase:
         self.host_process = psutil.Process(host_pid)
         self.child_process = None
         self.child_pid = None
+        self.enable_signal_chars = True
         
         logger.info("ConsoleReader started")
         
@@ -130,6 +133,8 @@ class ConsoleReaderBase:
                                                                              0, None, None, si)
                 self.child_process = psutil.Process(self.child_pid)
                 
+                logger.info(f'Child pid: {self.child_pid}  Console pid: {self.console_pid}')
+                
             except:
                 logger.info(traceback.format_exc())
                 return
@@ -176,6 +181,11 @@ class ConsoleReaderBase:
                 logger.debug(f'get_from_host: {s}')
             else:
                 logger.spam(f'get_from_host: {s}')
+            if self.enable_signal_chars:
+                for sig,char in SIGNAL_CHARS.items():
+                    if char in s:
+                        self.child_process.send_signal(sig)
+            s = s.decode()
             self.write(s)
             
             if cursorPos.Y > maxconsoleY and not paused:
@@ -201,7 +211,7 @@ class ConsoleReaderBase:
     def isalive(self, process):
         """True if the child is still alive, false otherwise"""
         try:
-            process.wait(timeout=0)
+            self.exitstatus = process.wait(timeout=0)
             return False
         except psutil.TimeoutExpired:
             return True
@@ -481,7 +491,7 @@ class ConsoleReaderSocket(ConsoleReaderBase):
             # timeout exception is setup
             if err == 'timed out':
                 logger.debug('recv timed out, retry later')
-                return ''
+                return b''
             else:
                 raise
         else:
@@ -489,7 +499,7 @@ class ConsoleReaderSocket(ConsoleReaderBase):
                 raise Exception('orderly shutdown on server end')
             else:
                 # got a message do something :)
-                return msg.decode()
+                return msg
     
     
 class ConsoleReaderPipe(ConsoleReaderBase):
@@ -526,6 +536,6 @@ class ConsoleReaderPipe(ConsoleReaderBase):
         if avail > 0:
             resp = win32file.ReadFile(self.pipe, 4096)
             ret = resp[1]
-            return ret.decode()
+            return ret
         else:
-            return ''
+            return b''

wexpect/host.py

@@ -89,6 +89,7 @@ from .wexpect_util import TIMEOUT
 from .wexpect_util import split_command_line
 from .wexpect_util import init_logger
 from .wexpect_util import EOF_CHAR
+from .wexpect_util import SIGNAL_CHARS
 
 logger = logging.getLogger('wexpect')
         
@@ -389,26 +390,10 @@ class SpawnBase:
         return self.console_process
     
     def get_child_process(self, force=False):
-        '''Fetches and returns the child process (and pid)
-        
-        The console starts the *real* child. This function fetches this *real* child's process ID
-        and process handle. If the console process is slower,(the OS does not grant enough CPU for
-        that), the child, cannot be started, when we reach this function, therefore the
-        `self.get_console_process().children()` line will return an empty list. So we ask console's child
-        in a loop, while, we found a (the) child.
-        This loop cannot be an infinite loop. If the console's process has error before/during
-        starting the child. `self.get_console_process().children()` will throw error.
-        '''
         if force or self.console_process is None:
-            while True:
+            self.child_process = self.get_console_process()
-                children = self.get_console_process().children()
+            self.child_pid = self.child_process.pid
-                try:
+            return self.child_process
-                    self.child_process = children[0]
-                except IndexError:
-                    time.sleep(.1)
-                    continue
-                self.child_pid = self.child_process.pid
-                return self.child_process
             
     def close(self):   # File-like object.
         """ Closes the child console."""
@@ -444,7 +429,7 @@ class SpawnBase:
         """Sig == sigint for ctrl-c otherwise the child is terminated."""
         try:
             self.child_process.send_signal(sig)
-        except psutil._exceptions.NoSuchProcess as e:
+        except psutil.NoSuchProcess as e:
             logger.info('Child has already died. %s', e)
     
     def wait(self, child=True, console=True):
@@ -562,8 +547,7 @@ class SpawnBase:
         """This is like send(), but it adds a line feed (os.linesep). This
         returns the number of bytes written. """
 
-        n = self.send(s)
+        n = self.send(s+'\r\n')
-        n = n + self.send(b'\r\n')
         return n
 
     def sendeof(self):
@@ -580,7 +564,18 @@ class SpawnBase:
         char = chr(4)
         self.send(char)
         
-    def send(self):
+    def send(self, s, delaybeforesend=None):
+        """Virtual definition
+        """
+        if delaybeforesend is None:
+            delaybeforesend = self.delaybeforesend
+            
+        if delaybeforesend:
+            time.sleep(delaybeforesend)
+            
+        return self._send_impl(s)
+        
+    def _send_impl(self, s):
         """Virtual definition
         """
         raise NotImplementedError
@@ -773,6 +768,8 @@ class SpawnBase:
             end_time = time.time() + timeout 
         if searchwindowsize == -1:
             searchwindowsize = self.searchwindowsize
+            
+        logger.debug(f'searcher: {searcher}')
 
         try:
             incoming = self.buffer
@@ -916,14 +913,12 @@ class SpawnPipe(SpawnBase):
             else:
                 raise
     
-    def send(self, s):
+    def _send_impl(self, s):
         """This sends a string to the child process. This returns the number of
         bytes written. If a log file was set then the data is also written to
         the log. """
         if isinstance(s, str):
             s = str.encode(s)
-        if self.delaybeforesend:
-            time.sleep(self.delaybeforesend)
         try:
             if s:
                 logger.debug(f"Writing: {s}")
@@ -942,6 +937,14 @@ class SpawnPipe(SpawnBase):
             else:
                 raise            
         return len(s)
+    
+    def kill(self, sig=signal.SIGTERM):
+        """Sig == sigint for ctrl-c otherwise the child is terminated."""
+        try:
+            logger.info(f'Sending kill signal: {sig}')
+            self.send(SIGNAL_CHARS[sig])
+        except EOF as e:
+            logger.info(e)
 
 
 class SpawnSocket(SpawnBase):
@@ -957,14 +960,12 @@ class SpawnSocket(SpawnBase):
         super().__init__(command=command, args=args, timeout=timeout, maxread=maxread,
              searchwindowsize=searchwindowsize, cwd=cwd, env=env, codepage=codepage, echo=echo, interact=interact)
         
-    def send(self, s):
+    def _send_impl(self, s):
         """This sends a string to the child process. This returns the number of
         bytes written. If a log file was set then the data is also written to
         the log. """
         if isinstance(s, str):
             s = str.encode(s)
-        if self.delaybeforesend:
-            time.sleep(self.delaybeforesend)
         self.sock.sendall(s)
         return len(s)
          
@@ -1015,7 +1016,15 @@ class SpawnSocket(SpawnBase):
             return ''
 
         return s.decode()
-
+    
+    def kill(self, sig=signal.SIGTERM):
+        """Sig == sigint for ctrl-c otherwise the child is terminated."""
+        try:
+            logger.info(f'Sending kill signal: {sig}')
+            self.send(SIGNAL_CHARS[sig])
+        except EOF as e:
+            logger.info(e)
+       
 
 class searcher_re (object):
     """This is regular expression string search helper for the

wexpect/legacy_wexpect.py

@@ -1125,19 +1125,15 @@ class Wtty:
         logger.info(f"Fetch child's process and pid...")
         
         while True:
-            logger.info(f"0")
             msg = win32gui.GetMessage(0, 0, 0)
-            logger.info(f"0b")
             childPid = msg[1][2]
             # Sometimes win32gui.GetMessage returns a bogus PID, so keep calling it
             # until we can successfully connect to the child or timeout is
             # reached
             if childPid:
                 try:
-                    logger.info(f"1")
                     self.__childProcess = win32api.OpenProcess(
                         win32con.PROCESS_TERMINATE | win32con.PROCESS_QUERY_INFORMATION, False, childPid)
-                    logger.info(f"2")
                     self.__conProcess = win32api.OpenProcess(
                         win32con.PROCESS_TERMINATE | win32con.PROCESS_QUERY_INFORMATION, False, self.conpid)
                 except pywintypes.error as e:

wexpect/wexpect_util.py

@@ -42,10 +42,16 @@ import traceback
 import sys
 import os
 import logging
+import signal
 
 # platform does not define VEOF so assume CTRL-D
 EOF_CHAR = b'\x04'
 
+SIGNAL_CHARS = {
+    signal.SIGTERM:  b'\x011', # Device control 1
+    signal.SIGINT:   b'\x012', # Device control 2
+                }
+
 SPAM = 5
 logging.addLevelName(SPAM, "SPAM")
 def spam(self, message, *args, **kws):