# HG changeset patch
# User Alexis S. L. Carvalho <alexis@cecm.usp.br>
# Date 1205448603 10800
# Node ID 0d0939b2d272bec33209de1dd559614f6b6e8d81
# Parent  b36774d0fce1f7d85a50f0618036f3fdda9ebde2
setup.py: skip inotify if there's no inotify_add_watch

Debian Etch doesn't include a sys/inotify.h header, which makes it
impossible to compile _inotify.c, making hg uninstallable.

The cc.has_function() method is implemented by trying to compile a
simple C program.  Since there's no redirection involved all error
messages are sent to the terminal.  This is not particularly pretty
but at least it allows the installation to complete.

diff -r b36774d0fce1 -r 0d0939b2d272 setup.py
--- a/setup.py	Thu Mar 13 17:39:30 2008 +0100
+++ b/setup.py	Thu Mar 13 19:50:03 2008 -0300
@@ -12,6 +12,7 @@
 import os
 from distutils.core import setup, Extension
 from distutils.command.install_data import install_data
+from distutils.ccompiler import new_compiler
 
 import mercurial.version
 
@@ -66,10 +67,13 @@
     ext_modules.append(Extension('mercurial.osutil', ['mercurial/osutil.c']))
 
     if sys.platform == 'linux2' and os.uname()[2] > '2.6':
-        # the inotify extension is only usable with Linux 2.6 kernels
-        ext_modules.append(Extension('hgext.inotify.linux._inotify',
-                                     ['hgext/inotify/linux/_inotify.c']))
-        packages.extend(['hgext.inotify', 'hgext.inotify.linux'])
+        # The inotify extension is only usable with Linux 2.6 kernels.
+        # You also need a reasonably recent C library.
+        cc = new_compiler()
+        if cc.has_function('inotify_add_watch'):
+            ext_modules.append(Extension('hgext.inotify.linux._inotify',
+                                         ['hgext/inotify/linux/_inotify.c']))
+            packages.extend(['hgext.inotify', 'hgext.inotify.linux'])
 except ImportError:
     pass