This reverts commit a5e1602090.
Getting rid of unistd.h from our headers will require more work than
just fixing the broken mingw build. Revert it until I have a more
complete proposal.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
util/virutil.h bogously included unistd.h. Drop it and replace it by
including it directly where needed.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
In many files there are header comments that contain an Author:
statement, supposedly reflecting who originally wrote the code.
In a large collaborative project like libvirt, any non-trivial
file will have been modified by a large number of different
contributors. IOW, the Author: comments are quickly out of date,
omitting people who have made significant contribitions.
In some places Author: lines have been added despite the person
merely being responsible for creating the file by moving existing
code out of another file. IOW, the Author: lines give an incorrect
record of authorship.
With this all in mind, the comments are useless as a means to identify
who to talk to about code in a particular file. Contributors will always
be better off using 'git log' and 'git blame' if they need to find the
author of a particular bit of code.
This commit thus deletes all Author: comments from the source and adds
a rule to prevent them reappearing.
The Copyright headers are similarly misleading and inaccurate, however,
we cannot delete these as they have legal meaning, despite being largely
inaccurate. In addition only the copyright holder is permitted to change
their respective copyright statement.
Reviewed-by: Erik Skultety <eskultet@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
All of the ones being removed are pulled in by internal.h. The only
exception is sanlock which expects the application to include <stdint.h>
before sanlock's headers, because sanlock prototypes use fixed width
int, but they don't include stdint.h themselves, so we have to leave
that one in place.
Signed-off-by: Erik Skultety <eskultet@redhat.com>
Acked-by: Michal Privoznik <mprivozn@redhat.com>
So far the virLockSpaceAcquireResource() locks the first byte in
the underlying file. But caller might want to lock other range.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Any source file which calls the logging APIs now needs
to have a VIR_LOG_INIT("source.name") declaration at
the start of the file. This provides a static variable
of the virLogSource type.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Commit a1cbe4b5 added a check for spaces around assignments and this
patch extends it to checks for spaces around '=='. One exception is
virAssertCmpInt where comma after '==' is acceptable (since it is a
macro and '==' is its argument).
Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
The test case average timing code has not been used by any test
case ever. Delete it to remove complexity.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
These all existed before virfile.c was created, and for some reason
weren't moved.
This is mostly straightfoward, although the syntax rule prohibiting
write() had to be changed to have an exception for virfile.c instead
of virutil.c.
This movement pointed out that there is a function called
virBuildPath(), and another almost identical function called
virFileBuildPath(). They really should be a single function, which
I'll take care of as soon as I figure out what the arglist should look
like.
The previously introduced virFile{Lock,Unlock} APIs provide a
way to acquire/release fcntl() locks on individual files. For
unknown reason though, the POSIX spec says that fcntl() locks
are released when *any* file handle referring to the same path
is closed. In the following sequence
threadA: fd1 = open("foo")
threadB: fd2 = open("foo")
threadA: virFileLock(fd1)
threadB: virFileLock(fd2)
threadB: close(fd2)
you'd expect threadA to come out holding a lock on 'foo', and
indeed it does hold a lock for a very short time. Unfortunately
when threadB does close(fd2) this releases the lock associated
with fd1. For the current libvirt use case for virFileLock -
pidfiles - this doesn't matter since the lock is acquired
at startup while single threaded an never released until
exit.
To provide a more generally useful API though, it is necessary
to introduce a slightly higher level abstraction, which is to
be referred to as a "lockspace". This is to be provided by
a virLockSpacePtr object in src/util/virlockspace.{c,h}. The
core idea is that the lockspace keeps track of what files are
already open+locked. This means that when a 2nd thread comes
along and tries to acquire a lock, it doesn't end up opening
and closing a new FD. The lockspace just checks the current
list of held locks and immediately returns VIR_ERR_RESOURCE_BUSY.
NB, the API as it stands is designed on the basis that the
files being locked are not being otherwise opened and used
by the application code. One approach to using this API is to
acquire locks based on a hash of the filepath.
eg to lock /var/lib/libvirt/images/foo.img the application
might do
virLockSpacePtr lockspace = virLockSpaceNew("/var/lib/libvirt/imagelocks");
lockname = md5sum("/var/lib/libvirt/images/foo.img");
virLockSpaceAcquireLock(lockspace, lockname);
NB, in this example, the caller should ensure that the path
is canonicalized before calculating the checksum.
It is also possible to do locks directly on resources by
using a NULL lockspace directory and then using the file
path as the lock name eg
virLockSpacePtr lockspace = virLockSpaceNew(NULL);
virLockSpaceAcquireLock(lockspace, "/var/lib/libvirt/images/foo.img");
This is only safe to do though if no other part of the process
will be opening the files. This will be the case when this
code is used inside the soon-to-be-reposted virlockd daemon
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
