Disables idle suspend on XO while any of the stopwatches are

running by James Cameron

1 files changed, 51 insertions, 0 deletions

diff --git a/powerd.py b/powerd.py
new file mode 100644
index 0000000..88b4e84
--- /dev/null
+++ b/powerd.py
@@ -0,0 +1,51 @@
+# Copyright (C) 2011 One Laptop per Child
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty ofwa
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+import os
+
+
+def marker():
+    """ filesystem path of per-process inhibit file """
+    return os.path.join('/var/run/powerd-inhibit-suspend', str(os.getpid()))
+
+
+class Suspend():
+    """ control of powerd idle suspend,
+        reference counted,
+        does nothing if powerd is not present """
+
+    def __init__(self):
+        self.references = 0
+
+    def inhibit(self):
+        """ inhibit suspend for this process """
+        if self.references == 0:
+            try:
+                file(marker(), 'w').write('')
+            except:
+                return
+        self.references += 1
+
+    def uninhibit(self):
+        """ uninhibit suspend for this process """
+        self.references -= 1
+        if self.references > 0:
+            return
+        try:
+            os.remove(marker())
+        except:
+            pass
+        self.references = 0