Merge lp:~schmichael/python-signalfd/helpers into lp:python-signalfd

[Michael Schurter]

Without a helper to parse the 128 byte (80 meaningful bytes) siginfo_t, signalfds are pretty difficult to use, so I added the relevant struct and a couple helpers. I'm not picky about whether or not this is the final API; I just wanted to get something there to make signalfds usable.

Thanks for the great module! Sorry to see it didn't make it into 3.2. Hopefully 3.3?

[lp:~schmichael/python-signalfd/helpers]

8. By Michael Schurter on 2011-02-21

Default to no flags in create_signalfd helper

9. By Michael Schurter on 2011-02-24

No need for copyright attribution

10. By Michael Schurter on 2011-02-24

Add basic bzrignore patterns

11. By Michael Schurter on 2011-02-24

Remove use of setuptools

12. By Michael Schurter on 2011-02-24

Match version in signalfd/__init__.py

13. By Michael Schurter on 2011-02-24

Switch to a simpler namedtuples like class for SigInfo

14. By Michael Schurter on 2011-02-24

Add some simple tests for {create_,read_}signalfd helpers

15. By Michael Schurter on 2011-02-24

Add a test for reading a nonblocking fd before it's ready

Unmerged revisions

15. By Michael Schurter on 2011-02-24

Add a test for reading a nonblocking fd before it's ready

14. By Michael Schurter on 2011-02-24

Add some simple tests for {create_,read_}signalfd helpers

13. By Michael Schurter on 2011-02-24

Switch to a simpler namedtuples like class for SigInfo

12. By Michael Schurter on 2011-02-24

Match version in signalfd/__init__.py

11. By Michael Schurter on 2011-02-24

Remove use of setuptools

10. By Michael Schurter on 2011-02-24

Add basic bzrignore patterns

9. By Michael Schurter on 2011-02-24

No need for copyright attribution

8. By Michael Schurter on 2011-02-21

Default to no flags in create_signalfd helper

7. By Michael Schurter on 2011-02-21

Add signalfd creation and reader helpers

=== modified file 'setup.py'
--- setup.py	2010-06-21 22:16:05 +0000
+++ setup.py	2011-02-21 06:26:50 +0000
@@ -1,7 +1,8 @@
 # Copyright (c) 2010 Jean-Paul Calderone
 # See LICENSE file for details.
 
-from distutils.core import Extension, setup
+from setuptools import setup
+from distutils.core import Extension
 
 setup(
     name="python-signalfd",

=== modified file 'signalfd/__init__.py'
--- signalfd/__init__.py	2010-06-21 22:11:44 +0000
+++ signalfd/__init__.py	2011-02-21 06:26:50 +0000
@@ -1,5 +1,8 @@
 # Copyright (c) 2010 Jean-Paul Calderone.
+# Copyright (c) 2011 Michael Schurter <[e-mail]>
 # See LICENSE file for details.
+import os
+import struct
 
 try:
     from signalfd._signalfd import \
@@ -12,10 +15,12 @@
         SIG_BLOCK, SIG_UNBLOCK, SIG_SETMASK, \
         SFD_CLOEXEC, SFD_NONBLOCK
 
-__version__ = '0.1'
-__version_info__ = (0, 1)
+__version__ = '0.2'
+__version_info__ = (0, 2)
 
 __all__ = [
+    'created_signalfd', 'read_signalfd', 'siginfo_t', 'SigInfo',
+
     'sigprocmask', 'signalfd',
 
     'SIG_BLOCK', 'SIG_UNBLOCK', 'SIG_SETMASK',
@@ -23,3 +28,105 @@
     'SFD_CLOEXEC', 'SFD_NONBLOCK',
 
     '__version__', '__version_info__']
+
+_signo_to_str = {
+        1: 'SIGHUP',
+        2: 'SIGINT',
+        3: 'SIGQUIT',
+        4: 'SIGILL',
+        5: 'SIGTRAP',
+        6: 'SIGABRT',
+        7: 'SIGBUS',
+        8: 'SIGFPE',
+        9: 'SIGKILL',
+        10: 'SIGUSR1',
+        11: 'SIGSEGV',
+        12: 'SIGUSR2',
+        13: 'SIGPIPE',
+        14: 'SIGALRM',
+        15: 'SIGTERM',
+        16: 'SIGSTKFLT',
+        17: 'SIGCHLD',
+        18: 'SIGCONT',
+        19: 'SIGSTOP',
+        20: 'SIGTSTP',
+        21: 'SIGTTIN',
+        22: 'SIGTTOU',
+        23: 'SIGURG',
+        24: 'SIGXCPU',
+        25: 'SIGXFSZ',
+        26: 'SIGVTALRM',
+        27: 'SIGPROF',
+        28: 'SIGWINCH',
+        29: 'SIGIO',
+        30: 'SIGPWR',
+        31: 'SIGSYS',
+        34: 'SIGRTMIN',
+        64: 'SIGRTMAX',
+    }
+
+def create_signalfd(signals, flags=0):
+    """Creates a new signal file descriptor
+
+    Shortcut for:
+        signalfd.sigprocmask(signalfd.SIG_BLOCK, signals)
+        signalfd(-1, signals, flags)
+    """
+    sigprocmask(SIG_BLOCK, signals)
+    return signalfd(-1, signals, flags)
+
+def read_signalfd(fd):
+    """Given a signalfd, return a SigInfo instance"""
+    return SigInfo(os.read(fd, siginfo_t.size))
+
+class SigInfo(object):
+    def __init__(self, data):
+        (self.ssi_signo,
+        self.ssi_errno,
+        self.ssi_code,
+        self.ssi_pid,
+        self.ssi_uid,
+        self.ssi_fd,
+        self.ssi_tid,
+        self.ssi_band,
+        self.ssi_overrun,
+        self.ssi_trapno,
+        self.ssi_status,
+        self.ssi_int,
+        self.ssi_ptr,
+        self.ssi_utime,
+        self.ssi_stime,
+        self.ssi_addr,
+        self.padding) = siginfo_t.unpack(data)
+
+    @property
+    def signo(self):
+        return self.ssi_signo
+
+    @property
+    def signal(self):
+        return _signo_to_str[self.ssi_signo]
+
+    def __str__(self):
+        return self.signal
+
+siginfo_t = struct.Struct(
+        'I' # ssi_signo   - Signal number
+        'i' # ssi_errno   - Error number (unused)
+        'i' # ssi_code    - Signal code
+        'I' # ssi_pid     - PID of sender
+        'I' # ssi_uid     - Real UID of sender
+        'i' # ssi_fd      - File descriptor (SIGIO)
+        'I' # ssi_tid     - Kernel timer ID (POSIX timers)
+        'I' # ssi_band    - Band event (SIGIO)
+        'I' # ssi_overrun - POSIX timer overrun count
+        'I' # ssi_trapno  - Trap number that caused signal
+        'i' # ssi_status  - Exit status or signal (SIGCHLD)
+        'i' # ssi_int     - Integer sent by sigqueue (2)
+        'Q' # ssi_ptr     - Pointer sent by sigqueue (2)
+        'Q' # ssi_utime   - User CPU time consumed (SIGCHLD)
+        'Q' # ssi_stime   - System CPU time consumed (SIGCHLD)
+        'Q' # ssi_addr    - Address that generated signal
+            #               (for hardware generated signals)
+        '48s' # pad[X]    - Pad size to 128 bytes for future use
+    )