merge from trunk at revno 799

1 files changed, 126 insertions, 35 deletions

diff --git a/cloudinit/util.py b/cloudinit/util.py
index dc3c5639..c961bbc7 100644
--- a/cloudinit/util.py
+++ b/cloudinit/util.py
@@ -43,15 +43,16 @@ import subprocess
 import sys
 import tempfile
 import time
-import types
 import urlparse
 
 import yaml
 
 from cloudinit import importer
 from cloudinit import log as logging
+from cloudinit import mergers
 from cloudinit import safeyaml
 from cloudinit import url_helper
+from cloudinit import type_utils
 from cloudinit import version
 
 from cloudinit.settings import (CFG_BUILTIN)
@@ -219,11 +220,12 @@ def fork_cb(child_cb, *args):
             os._exit(0)  # pylint: disable=W0212
         except:
             logexc(LOG, ("Failed forking and"
-                         " calling callback %s"), obj_name(child_cb))
+                         " calling callback %s"),
+                   type_utils.obj_name(child_cb))
             os._exit(1)  # pylint: disable=W0212
     else:
         LOG.debug("Forked child %s who will run callback %s",
-                  fid, obj_name(child_cb))
+                  fid, type_utils.obj_name(child_cb))
 
 
 def is_true(val, addons=None):
@@ -537,40 +539,26 @@ def make_url(scheme, host, port=None,
     return urlparse.urlunparse(pieces)
 
 
-def obj_name(obj):
-    if isinstance(obj, (types.TypeType,
-                        types.ModuleType,
-                        types.FunctionType,
-                        types.LambdaType)):
-        return str(obj.__name__)
-    return obj_name(obj.__class__)
-
-
 def mergemanydict(srcs, reverse=False):
     if reverse:
         srcs = reversed(srcs)
     m_cfg = {}
+    merge_how = [mergers.default_mergers()]
     for a_cfg in srcs:
         if a_cfg:
-            m_cfg = mergedict(m_cfg, a_cfg)
+            # Take the last merger as the one that
+            # will define how to merge next...
+            mergers_to_apply = list(merge_how[-1])
+            merger = mergers.construct(mergers_to_apply)
+            m_cfg = merger.merge(m_cfg, a_cfg)
+            # If the config has now has new merger set,
+            # extract them to be used next time...
+            new_mergers = mergers.dict_extract_mergers(m_cfg)
+            if new_mergers:
+                merge_how.append(new_mergers)
     return m_cfg
 
 
-def mergedict(src, cand):
-    """
-    Merge values from C{cand} into C{src}.
-    If C{src} has a key C{cand} will not override.
-    Nested dictionaries are merged recursively.
-    """
-    if isinstance(src, dict) and isinstance(cand, dict):
-        for (k, v) in cand.iteritems():
-            if k not in src:
-                src[k] = v
-            else:
-                src[k] = mergedict(src[k], v)
-    return src
-
-
 @contextlib.contextmanager
 def chdir(ndir):
     curr = os.getcwd()
@@ -713,7 +701,7 @@ def load_yaml(blob, default=None, allowed=(dict,)):
             # Yes this will just be caught, but thats ok for now...
             raise TypeError(("Yaml load allows %s root types,"
                              " but got %s instead") %
-                            (allowed, obj_name(converted)))
+                            (allowed, type_utils.obj_name(converted)))
         loaded = converted
     except (yaml.YAMLError, TypeError, ValueError):
         if len(blob) == 0:
@@ -782,7 +770,7 @@ def read_conf_with_confd(cfgfile):
             if not isinstance(confd, (str, basestring)):
                 raise TypeError(("Config file %s contains 'conf_d' "
                                  "with non-string type %s") %
-                                 (cfgfile, obj_name(confd)))
+                                 (cfgfile, type_utils.obj_name(confd)))
             else:
                 confd = str(confd).strip()
     elif os.path.isdir("%s.d" % cfgfile):
@@ -793,7 +781,7 @@ def read_conf_with_confd(cfgfile):
 
     # Conf.d settings override input configuration
     confd_cfg = read_conf_d(confd)
-    return mergedict(confd_cfg, cfg)
+    return mergemanydict([confd_cfg, cfg])
 
 
 def read_cc_from_cmdline(cmdline=None):
@@ -948,7 +936,7 @@ def is_resolvable(name):
                 for (_fam, _stype, _proto, cname, sockaddr) in result:
                     badresults[iname].append("%s: %s" % (cname, sockaddr[0]))
                     badips.add(sockaddr[0])
-            except socket.gaierror:
+            except (socket.gaierror, socket.error):
                 pass
         _DNS_REDIRECT_IP = badips
         if badresults:
@@ -961,7 +949,7 @@ def is_resolvable(name):
         if addr in _DNS_REDIRECT_IP:
             return False
         return True
-    except socket.gaierror:
+    except (socket.gaierror, socket.error):
         return False
 
 
@@ -1540,7 +1528,7 @@ def shellify(cmdlist, add_header=True):
         else:
             raise RuntimeError(("Unable to shellify type %s"
                                 " which is not a list or string")
-                               % (obj_name(args)))
+                               % (type_utils.obj_name(args)))
     LOG.debug("Shellified %s commands.", cmds_made)
     return content
 
@@ -1599,7 +1587,7 @@ def get_proc_env(pid):
     fn = os.path.join("/proc/", str(pid), "environ")
     try:
         contents = load_file(fn)
-        toks = contents.split("\0")
+        toks = contents.split("\x00")
         for tok in toks:
             if tok == "":
                 continue
@@ -1655,3 +1643,106 @@ def expand_package_list(version_fmt, pkgs):
             raise RuntimeError("Invalid package type.")
 
     return pkglist
+
+
+def parse_mount_info(path, mountinfo_lines, log=LOG):
+    """Return the mount information for PATH given the lines from
+    /proc/$$/mountinfo."""
+
+    path_elements = [e for e in path.split('/') if e]
+    devpth = None
+    fs_type = None
+    match_mount_point = None
+    match_mount_point_elements = None
+    for i, line in enumerate(mountinfo_lines):
+        parts = line.split()
+
+        # Completely fail if there is anything in any line that is
+        # unexpected, as continuing to parse past a bad line could
+        # cause an incorrect result to be returned, so it's better
+        # return nothing than an incorrect result.
+
+        # The minimum number of elements in a valid line is 10.
+        if len(parts) < 10:
+            log.debug("Line %d has two few columns (%d): %s",
+                      i + 1, len(parts), line)
+            return None
+
+        mount_point = parts[4]
+        mount_point_elements = [e for e in mount_point.split('/') if e]
+
+        # Ignore mounts deeper than the path in question.
+        if len(mount_point_elements) > len(path_elements):
+            continue
+
+        # Ignore mounts where the common path is not the same.
+        l = min(len(mount_point_elements), len(path_elements))
+        if mount_point_elements[0:l] != path_elements[0:l]:
+            continue
+
+        # Ignore mount points higher than an already seen mount
+        # point.
+        if (match_mount_point_elements is not None and
+            len(match_mount_point_elements) > len(mount_point_elements)):
+            continue
+
+        # Find the '-' which terminates a list of optional columns to
+        # find the filesystem type and the path to the device.  See
+        # man 5 proc for the format of this file.
+        try:
+            i = parts.index('-')
+        except ValueError:
+            log.debug("Did not find column named '-' in line %d: %s",
+                      i + 1, line)
+            return None
+
+        # Get the path to the device.
+        try:
+            fs_type = parts[i + 1]
+            devpth = parts[i + 2]
+        except IndexError:
+            log.debug("Too few columns after '-' column in line %d: %s",
+                      i + 1, line)
+            return None
+
+        match_mount_point = mount_point
+        match_mount_point_elements = mount_point_elements
+
+    if devpth and fs_type and match_mount_point:
+        return (devpth, fs_type, match_mount_point)
+    else:
+        return None
+
+
+def get_mount_info(path, log=LOG):
+    # Use /proc/$$/mountinfo to find the device where path is mounted.
+    # This is done because with a btrfs filesystem using os.stat(path)
+    # does not return the ID of the device.
+    #
+    # Here, / has a device of 18 (decimal).
+    #
+    # $ stat /
+    #   File: '/'
+    #   Size: 234               Blocks: 0          IO Block: 4096   directory
+    # Device: 12h/18d   Inode: 256         Links: 1
+    # Access: (0755/drwxr-xr-x)  Uid: (    0/    root)   Gid: (    0/    root)
+    # Access: 2013-01-13 07:31:04.358011255 +0000
+    # Modify: 2013-01-13 18:48:25.930011255 +0000
+    # Change: 2013-01-13 18:48:25.930011255 +0000
+    #  Birth: -
+    #
+    # Find where / is mounted:
+    #
+    # $ mount | grep ' / '
+    # /dev/vda1 on / type btrfs (rw,subvol=@,compress=lzo)
+    #
+    # And the device ID for /dev/vda1 is not 18:
+    #
+    # $ ls -l /dev/vda1
+    # brw-rw---- 1 root disk 253, 1 Jan 13 08:29 /dev/vda1
+    #
+    # So use /proc/$$/mountinfo to find the device underlying the
+    # input path.
+    mountinfo_path = '/proc/%s/mountinfo' % os.getpid()
+    lines = load_file(mountinfo_path).splitlines()
+    return parse_mount_info(path, lines, log)