[Python-checkins] cpython (2.7): Issue #10963: Ensure that subprocess.communicate() never raises EPIPE.

[ross.lagerwall]

http://hg.python.org/cpython/rev/c10d55c51d81
changeset:   69153:c10d55c51d81
branch:      2.7
parent:      69125:f961e9179998
user:        Ross Lagerwall <rosslagerwall at gmail.com>
date:        Tue Apr 05 15:24:34 2011 +0200
summary:
  Issue #10963: Ensure that subprocess.communicate() never raises EPIPE.

files:
  Lib/subprocess.py           |  45 ++++++++++++++++++------
  Lib/test/test_subprocess.py |  18 ++++++++++
  Misc/NEWS                   |   2 +
  3 files changed, 54 insertions(+), 11 deletions(-)


diff --git a/Lib/subprocess.py b/Lib/subprocess.py
--- a/Lib/subprocess.py
+++ b/Lib/subprocess.py
@@ -396,6 +396,7 @@
 import traceback
 import gc
 import signal
+import errno
 
 # Exception classes used by this module.
 class CalledProcessError(Exception):
@@ -427,7 +428,6 @@
 else:
     import select
     _has_poll = hasattr(select, 'poll')
-    import errno
     import fcntl
     import pickle
 
@@ -726,7 +726,11 @@
             stderr = None
             if self.stdin:
                 if input:
-                    self.stdin.write(input)
+                    try:
+                        self.stdin.write(input)
+                    except IOError as e:
+                        if e.errno != errno.EPIPE and e.errno != errno.EINVAL:
+                            raise
                 self.stdin.close()
             elif self.stdout:
                 stdout = self.stdout.read()
@@ -956,7 +960,11 @@
 
             if self.stdin:
                 if input is not None:
-                    self.stdin.write(input)
+                    try:
+                        self.stdin.write(input)
+                    except IOError as e:
+                        if e.errno != errno.EPIPE:
+                            raise
                 self.stdin.close()
 
             if self.stdout:
@@ -1336,9 +1344,16 @@
                 for fd, mode in ready:
                     if mode & select.POLLOUT:
                         chunk = input[input_offset : input_offset + _PIPE_BUF]
-                        input_offset += os.write(fd, chunk)
-                        if input_offset >= len(input):
-                            close_unregister_and_remove(fd)
+                        try:
+                            input_offset += os.write(fd, chunk)
+                        except OSError as e:
+                            if e.errno == errno.EPIPE:
+                                close_unregister_and_remove(fd)
+                            else:
+                                raise
+                        else:
+                            if input_offset >= len(input):
+                                close_unregister_and_remove(fd)
                     elif mode & select_POLLIN_POLLPRI:
                         data = os.read(fd, 4096)
                         if not data:
@@ -1377,11 +1392,19 @@
 
                 if self.stdin in wlist:
                     chunk = input[input_offset : input_offset + _PIPE_BUF]
-                    bytes_written = os.write(self.stdin.fileno(), chunk)
-                    input_offset += bytes_written
-                    if input_offset >= len(input):
-                        self.stdin.close()
-                        write_set.remove(self.stdin)
+                    try:
+                        bytes_written = os.write(self.stdin.fileno(), chunk)
+                    except OSError as e:
+                        if e.errno == errno.EPIPE:
+                            self.stdin.close()
+                            write_set.remove(self.stdin)
+                        else:
+                            raise
+                    else:
+                        input_offset += bytes_written
+                        if input_offset >= len(input):
+                            self.stdin.close()
+                            write_set.remove(self.stdin)
 
                 if self.stdout in rlist:
                     data = os.read(self.stdout.fileno(), 1024)
diff --git a/Lib/test/test_subprocess.py b/Lib/test/test_subprocess.py
--- a/Lib/test/test_subprocess.py
+++ b/Lib/test/test_subprocess.py
@@ -597,6 +597,24 @@
         self.assertFalse(os.path.exists(ofname))
         self.assertFalse(os.path.exists(efname))
 
+    def test_communicate_epipe(self):
+        # Issue 10963: communicate() should hide EPIPE
+        p = subprocess.Popen([sys.executable, "-c", 'pass'],
+                             stdin=subprocess.PIPE,
+                             stdout=subprocess.PIPE,
+                             stderr=subprocess.PIPE)
+        self.addCleanup(p.stdout.close)
+        self.addCleanup(p.stderr.close)
+        self.addCleanup(p.stdin.close)
+        p.communicate("x" * 2**20)
+
+    def test_communicate_epipe_only_stdin(self):
+        # Issue 10963: communicate() should hide EPIPE
+        p = subprocess.Popen([sys.executable, "-c", 'pass'],
+                             stdin=subprocess.PIPE)
+        self.addCleanup(p.stdin.close)
+        time.sleep(2)
+        p.communicate("x" * 2**20)
 
 # context manager
 class _SuppressCoreFiles(object):
diff --git a/Misc/NEWS b/Misc/NEWS
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -47,6 +47,8 @@
 Library
 -------
 
+- Issue #10963: Ensure that subprocess.communicate() never raises EPIPE.
+
 - Issue #11662: Make urllib and urllib2 ignore redirections if the
   scheme is not HTTP, HTTPS or FTP (CVE-2011-1521).
 

-- 
Repository URL: http://hg.python.org/cpython