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# Date Author Comment
5f6515b6 02/26/2014 02:06 pm Petr Pudlak

A separate module for functions for atomic file operations

Utils is getting too big, so better split this new set of functions into
a separate sub-module. This also allows us to use ResultG there.

Signed-off-by: Petr Pudlak <>
Reviewed-by: Klaus Aehlig <>

a2a1a8ca 02/14/2014 11:47 am Petr Pudlak

Add functions for atomic operations on files

Function 'atomicUpdateFile' extends 'atomicWriteFile' that allows any
action to be run on a temporary file.

Function 'atomicUpdateLockedFile' additionally locks the original file
using flock and checks if its state conforms to the last one....

69bf84e1 02/04/2014 04:30 pm Petr Pudlak

Catch errors in 'lockFile' in Ganeti.Utils

Opening a file can fail as well, so catch errors there too.

Signed-off-by: Petr Pudlak <>
Reviewed-by: Klaus Aehlig <>

0c09ecc2 01/29/2014 03:12 pm Klaus Aehlig

Make safeRenameFile create dirs with defined permissions

If, and only if, safeRenameFile creates a new directory, make sure
it has well defined permissions. While there, also optimize for the
common case. The main use of safeRenameFile is archiving jobs. As...

96a4ebb8 01/29/2014 03:12 pm Klaus Aehlig

Add utility to fix permissions

Especially when creating new directories, we need to make sure
ownership and permissions are set correctly. Provide a function
to do so.

Signed-off-by: Klaus Aehlig <>
Reviewed-by: Petr Pudlak <>

ac81a213 01/29/2014 03:12 pm Klaus Aehlig

Add data type describing permissions and possibly owners

When creating new files, and, more importantly, new directories
it is relevant to set permissions, and possibly owners, correctly.
Provide a type specifying the target configuration.

Signed-off-by: Klaus Aehlig <>...

b3f95121 01/24/2014 02:38 pm Klaus Aehlig

Provide a safe version of rename

...that also creates the target directory, if needed.

Signed-off-by: Klaus Aehlig <>
Reviewed-by: Petr Pudlak <>

e97cce9f 12/20/2013 03:49 pm Klaus Aehlig

Reinstantiate inotify after a lost file

When watching a file, reinstantiate the inotify if notified
of an event that removes the watch. Such events are likely
to happen, as our usual way to "modify" a file is to atomically
replace it by another one.

Signed-off-by: Klaus Aehlig <>...

2f575937 12/20/2013 03:49 pm Klaus Aehlig

Improve debug-logging for watch file

Also log, at debug level only, when a change of a watched
file was observed, but the change did not result in any
change of derived value.

Signed-off-by: Klaus Aehlig <>
Reviewed-by: Helga Velroyen <>

13b05c27 12/20/2013 03:49 pm Klaus Aehlig

Improve debugging by logging inotify events

At debug level, not only log that an inotify triggered,
but also log the actual event.

Signed-off-by: Klaus Aehlig <>
Reviewed-by: Helga Velroyen <>

f18aaff4 12/16/2013 05:45 pm Klaus Aehlig

Fix race in watchFile

As the calling of watchFile and the evaluation of the initial
getFStatSafe takes non-zero time, the file could have changed
before inotify was set up properly. Solve this problem by an
additional check for the watched value to have changed immediately...

6eeaf385 12/10/2013 01:32 pm Klaus Aehlig

Add a generic function capable of watching a file

Add a method to return the new value of a function if it changes within
the given timeout. If not, return the old value. Make use of the fact,
that the function only changes, if the specified file changes on disk....

751fb9e2 12/10/2013 01:32 pm Klaus Aehlig

Add a safe version of getFStat

The function getFStat causes an IOError if the file to be stated does
not exist. In some cases, however, the only thing we care about is whether
it has changed, with disappearing being a legitimate change. So add a wrapper
that catches the IOError and returns nullFStat....

a0ee4f12 12/04/2013 05:52 pm Klaus Aehlig

Export getFStat from Utils

Signed-off-by: Klaus Aehlig <>
Reviewed-by: Petr Pudlak <>

ef8b6bcf 12/03/2013 12:50 pm Klaus Aehlig

Add a new unit parsing function taking all suffixes binary

In python, when parsing units (like disk sizes) we take all
suffixes (M, G, T) as 1024-based. To be backwards compatible
while moving to job management to luxid, in particular on RAPI,
add such a parsing function in haskell as well....

6fd8ceff 12/02/2013 04:08 pm Klaus Aehlig

Move FStat related function to Utils

In this way, the functions to to decide, based on fstat, whether
a file needs to be reloaded can used by other parts as well,
in particular to monitor progress in the job queue.

Signed-off-by: Klaus Aehlig <>...

32b07c5f 11/08/2013 07:00 pm Klaus Aehlig

Provide means of locking a file

Two avoid two processes simultaneously accessing the same
on-file structure, like the job queue, file locks are used.
Therefore, provide this functionality in Haskell as well.

Signed-off-by: Klaus Aehlig <>...

bf7ee7ad 11/08/2013 07:00 pm Klaus Aehlig

Provide function to obtain the unique element of a list

This version of 'the' properly lives in the 'Result' monad,
as opposed to traditional one calling 'error'. The reason
why it is 'Bad' that not precisely one element is returned
is given as argument....

5badb3e7 11/08/2013 06:59 pm Klaus Aehlig

Add utility function tryAndLogIOError

This function allows to use 'IO a' objects in a safe
way, using the 'try' function; the outcome is reported
as a 'Result'. IOErrors are logged and the result is
'Bad', while in the case of no errors, a result-yielding...

710f5ae2 11/08/2013 06:59 pm Klaus Aehlig

Provide utility to atomically write a file

To keep our on-file data consistent at any moment, we change
file contents by atomically replacing the file with a new one.

Signed-off-by: Klaus Aehlig <>
Reviewed-by: Michele Tartara <>

88b58ed6 10/16/2013 08:57 pm Hrvoje Ribicic

Add instance disk fields

The instance disk fields have been added. As these are the first
fields to be duplicated, some helper functions are present to support
easier specification of fields which have to be duplicated for every
entry in an array of configuration objects, and numbered accordingly....

06fd57e5 09/19/2013 11:52 am Jose A. Lopes

Fetch 'randomUuidFile' from 'ConstantUtils'

In 'Ganeti.Utils', update the reference to 'randomUuidFile' to fetch
the value from 'Ganeti.ConstantUtils' instead of the Python to Haskell
generated constant. This allows breaking the dependency of
'Ganeti.Utils' on the constants module, which in turn will allow...

f148fe23 08/27/2013 03:04 pm Klaus Aehlig

Merge branch 'stable-2.8' into stable-2.9

  • stable-2.8
    Add function to unwrap Results logging failures
    Make the DRBD collector more failure-resilient
    Prepare GetLinuxNodeInfo for testing
    Add unit test for GetLinuxNodeInfo
    NEWS update and version bump for 2.8 rc2...
838393d1 08/21/2013 06:18 pm Michele Tartara

Add function to unwrap Results logging failures

Add logWarningIfBad, a utility function similar to exitIfBad, that logs a
warning and returns a default value instead of just crashing the program if
the unpacked value is Bad.

Signed-off-by: Michele Tartara <>...

858ecf2b 07/18/2013 06:32 pm Klaus Aehlig

Merge branch 'stable-2.8' into stable-2.9

  • stable-2.8
    Fix permission problem related to Issue 477
    Add hs function to easily change file ownership

Conflicts:
src/Ganeti/Utils.hs (trivial)
trivial

Signed-off-by: Klaus Aehlig <>
Reviewed-by: Michele Tartara <>

a39cd547 07/18/2013 11:34 am Michele Tartara

Add hs function to easily change file ownership

The Haskell library functions only allow to change file ownership using
uid/gid. A function for doing that with explicit names is added by this
commit.

Signed-off-by: Michele Tartara <>
Reviewed-by: Iustin Pop <>

986a8671 05/14/2013 08:06 pm Michele Tartara

Factor out resolveAddr function

This function can be useful to many parts of the code to convert the string
representation of an IP (v4 or v6) address into the proper data type.

Signed-off-by: Michele Tartara <>
Reviewed-by: Helga Velroyen <>

7dbe4c72 04/19/2013 02:54 pm Klaus Aehlig

Make hroller insist on finding precisely one master node

As people rely on the master node being the last node of the last
group, make hroller fail, if no master node could be found in the
cluster. This happens, e.g., if a backend format is used that does not...

da9e2aff 02/20/2013 06:47 pm Iustin Pop

Add two utility functions for handling Either lists

These two functions permit operating in bulk on only the Left or Right
values in the original list, then reassembling the list back in the
original order.

Signed-off-by: Iustin Pop <>
Reviewed-by: Michele Tartara <>

3c296f56 02/12/2013 03:25 pm Michael Hanselmann

Merge branch 'devel-2.7'

  • devel-2.7: (23 commits)
    QA: Support additional arguments for initialization
    qa_utils: Fix order of arguments passed to _AssertRetCode
    Improve reporting on errors.AddressPoolError exceptions
    Add note about lv-tags rename...
72747d91 02/07/2013 06:14 pm Iustin Pop

Remove use of 'head' and add hlint warning for it

Since 'head' is unsafe to use in most cases, this patch removes its
use from most of the code, adds a lint warning for it (and for tail as
well), and adds override annotations in the few cases where it's
actually OK to use it (mainly when using head over the result of...

94042ae4 02/06/2013 02:16 pm Michele Tartara

Fix improperly formatted docstring

Change the docstring of chompPrefix to prevent the error
"doc comment parse failed" that was raised by some version of
haddock while generating the documentation for this function.

Signed-off-by: Michele Tartara <>...

a6e054a8 01/21/2013 01:57 pm Iustin Pop

Add a function to get the current time in microseconds

In some cases we need higher resolution that seconds; I've settled on
microseconds as that is what 'threadDelay' wants, for exactly, so it's
easier if we keep the same units.

Signed-off-by: Iustin Pop <>...

9fb621af 01/18/2013 12:41 pm Yiannis Tsiouris

Text wrap in Haskell code

This adds two functions in Utils.hs: 'wrap' and 'trim' along with some
simple tests. 'wrap' is used in Common.hs for wrapping command
descriptions to a fixed line length, e.g. useful for the "--help"
option.

Signed-off-by: Yiannis Tsiouris <>...

ace37e24 01/16/2013 03:56 pm Michele Tartara

Move getCurrentTime from Confd.Utils to Utils

The getCurrentTime function is of wide interest, so its moved to a more
appropriate position.

Signed-off-by: Michele Tartara <>
Reviewed-by: Iustin Pop <>

a7f0953a 01/15/2013 04:27 pm Iustin Pop

Make niceSort a wrapper over niceSortKey id

Currently, niceSort behaves differently than niceSortKey in cases
where the parsed groups are equal but the original not, as it uses
both members of the tuple as opposed to just the first one. Both
niceSortKey and the Python code use only the first one, so in corner...

b6aeda4a 01/14/2013 05:54 pm Dato Simó

Utils.hs: add a clockTimeToString function

This function allows to easily convert a ClockTime object to a string
representation of its timestamp (seconds-only).

Signed-off-by: Dato Simó <>
Reviewed-by: Iustin Pop <>

b009f682 01/14/2013 05:54 pm Dato Simó

Utils.hs: function to chomp prefix + separator from a string

Some auto-repair tags are composed of a prefix and then an optional
argument; the new "chompPrefix" function in Utils.hs allows to strip a
prefix, allowing the last character (the separator) to be absent if there...

3add7574 12/24/2012 11:38 pm Iustin Pop

Rename htools/ to src/

Per offline discussions, this is the first patch of the
renames. Tested with "make distcheck", seems to work fine.

The only change outside of the renaming is a bit of simplification in
the .gitignore rules; otherwise, simply s/htools/src/....