From 74cbc138780f125b5752d150125cd0871efce72d Mon Sep 17 00:00:00 2001
From: Tomeu Vizoso <tomeu@tomeuvizoso.net>
Date: Tue, 06 Nov 2007 16:25:49 +0000
Subject: #4654 Hard link files on check out instead of copying if possible.

---
diff --git a/NEWS b/NEWS
index 197596d..81437b3 100644
--- a/NEWS
+++ b/NEWS
@@ -1,3 +1,5 @@
+* #4654 Hard link files on check out instead of copying if possible. (tomeu)
+
 Snapshot 2b5596554c
 
 * #4234 Fix copying a download to an usb stick. (marco)
diff --git a/src/olpc/datastore/backingstore.py b/src/olpc/datastore/backingstore.py
index e0e420b..a841f73 100644
--- a/src/olpc/datastore/backingstore.py
+++ b/src/olpc/datastore/backingstore.py
@@ -19,6 +19,8 @@ import sha
 import subprocess
 import time
 import threading
+import errno
+import shutil
 
 import dbus
 import xapian
@@ -343,11 +345,12 @@ class FileBackingStore(BackingStore):
         return os.path.join(self.base, str(uid))
 
     def _targetFile(self, uid, target=None, ext=None, env=None):
+        logging.debug('FileBackingStore._targetFile: %r %r %r %r' % (uid, target, ext, env))
         # paths out of the datastore, working copy targets
         path = self._translatePath(uid)
         if not os.path.exists(path):
             return None
-        
+
         if target: targetpath = target
         else:
             targetpath = uid.replace('/', '_').replace('.', '__')
@@ -355,8 +358,12 @@ class FileBackingStore(BackingStore):
                 if not ext.startswith('.'): ext = ".%s" % ext
                 targetpath = "%s%s" % (targetpath, ext)
 
-        base = '/tmp'
-        if env: base = env.get('cwd', base)
+        # TODO: When rainbow can tell us, we'll save the file to a dir inside the
+        # activity file space.
+        profile = os.environ.get('SUGAR_PROFILE', 'default')
+        base = os.path.join(os.path.expanduser('~'), '.sugar', profile, 'data')
+        if not os.path.exists(base):
+            os.makedirs(base)
         
         targetpath = os.path.join(base, targetpath)
         attempt = 0
@@ -375,10 +382,16 @@ class FileBackingStore(BackingStore):
                 break
 
             targetpath = "%s(%s)%s" % (targetpath, attempt, ext)
+
+        try:
+            os.link(path, targetpath)
+        except OSError, e:
+            if e.errno == errno.EXDEV:
+                shutil.copy(path, targetpath)
+            else:
+                raise
             
-        if subprocess.call(['cp', path, targetpath]):
-            raise OSError("unable to create working copy")
-        return open(targetpath, 'rw')
+        return open(targetpath, 'r')
             
     def _mapContent(self, uid, fp, path, env=None):
         """map a content object and the file in the repository to a
diff --git a/src/olpc/datastore/model.py b/src/olpc/datastore/model.py
index 9b00e2c..4558a10 100644
--- a/src/olpc/datastore/model.py
+++ b/src/olpc/datastore/model.py
@@ -260,11 +260,8 @@ class Content(object):
         if not hasattr(self, "_file") or not self._file or \
                self._file.closed is True:
             target, ext = self.suggestName()
-            try:
-                targetfile = self.backingstore._targetFile(self.id, target, ext)
-                self._file = targetfile
-            except OSError:
-                self._file = None
+            targetfile = self.backingstore._targetFile(self.id, target, ext)
+            self._file = targetfile
         return self._file
     
     def set_file(self, fileobj):
--
cgit v0.9.1