Use blocking mode for writes since we'd rather block than trigger a EWOULDBLOCK error.

svn path=/main/trunk/; revision=7391

diff --git a/pym/portage/__init__.py b/pym/portage/__init__.py
index df32b6c8e4e301c8b987222122d66f181fe99532..1fb8bb92fb86d9b87af81c11bf96bd51e0ad5d51 100644 (file)
--- a/pym/portage/__init__.py
+++ b/pym/portage/__init__.py
@@ -2477,18 +2477,20 @@ def spawn(mystring, mysettings, debug=0, free=0, droppriv=0, sesandbox=0, fakero
 
        if logfile:
                log_file = open(logfile, 'a')
-               import array, fcntl, select
-               # Use non-blocking mode to prevent read
-               # calls from blocking indefinitely.
-               for fd in fd_pipes_orig[0], master_fd:
-                       fd_flags = fcntl.fcntl(fd, fcntl.F_GETFL)
-                       fcntl.fcntl(fd, fcntl.F_SETFL, fd_flags | os.O_NONBLOCK)
                stdin_file = os.fdopen(os.dup(fd_pipes_orig[0]), 'r')
                stdout_file = os.fdopen(os.dup(fd_pipes_orig[1]), 'w')
                master_file = os.fdopen(master_fd, 'w+')
                iwtd = [stdin_file, master_file]
                owtd = []
                ewtd = []
+               import array, fcntl, select
+               # Use non-blocking mode to prevent read
+               # calls from blocking indefinitely.
+               fd_flags = {}
+               for f in iwtd:
+                       fd_flags[f] = fcntl.fcntl(f.fileno(), fcntl.F_GETFL)
+                       fcntl.fcntl(f.fileno(), fcntl.F_SETFL,
+                               fd_flags[f] | os.O_NONBLOCK)
                buffsize = 65536
                eof = False
                while not eof:
@@ -2502,14 +2504,28 @@ def spawn(mystring, mysettings, debug=0, free=0, droppriv=0, sesandbox=0, fakero
                                if not buf:
                                        eof = True
                                        break
+                               # Use blocking mode for writes since we'd rather block than
+                               # trigger a EWOULDBLOCK error.
                                if f is stdin_file:
+                                       fcntl.fcntl(master_file.fileno(),
+                                               fcntl.F_SETFL, fd_flags[f])
                                        buf.tofile(master_file)
                                        master_file.flush()
+                                       fcntl.fcntl(master_file.fileno(),
+                                               fcntl.F_SETFL, fd_flags[f] | os.O_NONBLOCK)
                                else:
+                                       # stdout usually shares the O_NONBLOCK flag with stdin
+                                       fcntl.fcntl(stdin_file.fileno(),
+                                               fcntl.F_SETFL, fd_flags[f])
                                        buf.tofile(stdout_file)
                                        stdout_file.flush()
+                                       fcntl.fcntl(stdin_file.fileno(),
+                                               fcntl.F_SETFL, fd_flags[f] | os.O_NONBLOCK)
                                        buf.tofile(log_file)
                                        log_file.flush()
+               # Restore them to blocking mode.
+               for f in iwtd:
+                       fcntl.fcntl(f.fileno(), fcntl.F_SETFL, fd_flags[f])
                log_file.close()
                stdin_file.close()
                stdout_file.close()