dnf: fix Exception handling for class ProcessLock

Yocto based systems will sometimes have log_lock.pid left in target
filesystems.  Users typing 'ls /' will notice it, and will never be
removed.

It happened when log rotate happened, refer [1], since the problem
descripted in patch 0001-lock.py-fix-Exception-handling.patch, file
log_lock.pid will not be removed after dnf exit. For target system,
refer [4], dnf have a solution to remove it. But for OE, refer commit
[2][3], for fix another issue, OE changed log_lock.pid to root dir for
native dnf, so solution in [4] not works for log_lock.pid under "/", so
it will always exist under "/" of target system.

Use patch 0001-lock.py-fix-Exception-handling.patch to fix the problem.

[1] https://github.com/rpm-software-management/dnf/blob/a6d82221ae32045f0f788708a52d2f2bf5c5740b/dnf/logging.py#L127C31-L127C42
[2] https://git.openembedded.org/openembedded-core/commit/?id=742a1b71249f4da1c8d8e13e270b0eb6128a3f66
[3] https://git.openembedded.org/openembedded-core/commit/?id=7610f81586bd475f28fd3d89a7350771720c3264
[4] https://github.com/rpm-software-management/dnf/blob/master/etc/tmpfiles.d/dnf.conf

(From OE-Core rev: d86c0e3468504c6ed19e38750abbb8970b5b7691)

Signed-off-by: Changqing Li <changqing.li@windriver.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

2 files changed, 63 insertions, 0 deletions

diff --git a/meta/recipes-devtools/dnf/dnf/0001-lock.py-fix-Exception-handling.patch b/meta/recipes-devtools/dnf/dnf/0001-lock.py-fix-Exception-handling.patch
new file mode 100644
index 0000000000..6bffe9af0a
--- /dev/null
+++ b/meta/recipes-devtools/dnf/dnf/0001-lock.py-fix-Exception-handling.patch
@@ -0,0 +1,62 @@
+From 3881757eabfde2ff54400ab127b106ab085d83f0 Mon Sep 17 00:00:00 2001
+From: Changqing Li <changqing.li@windriver.com>
+Date: Wed, 13 Mar 2024 11:22:05 +0800
+Subject: [PATCH] lock.py: fix Exception handling
+
+Before, when logdir is not writable, _try_lock will raise an Exception
+like "Permission denied: '/var/log/log_lock.pid'", and in this case,
+_unlock_thread will not be called and the variable count will not be
+handled, it maybe cause log_lock.pid not be deleted in case like [1].
+
+For [1], it is an cross compile case, when dnf install some packages to
+rootfs, seems like some threads don't do chroot like work, some threads
+do chroot like work. so for the threads don't do chroot, "Permission denied"
+Exception happend, for the threads that do chroot, log_lock.pid will be
+created under installroot/var/log/log_lock.pid, since variable count not
+handled correct before, log_lock.pid may not be deleted correctly.
+
+So fixed like this, if _try_lock raise Exception, _unlock_thread first,
+then raise the Exception.
+
+[1] https://github.com/rpm-software-management/dnf/issues/1963
+
+Upstream-Status: Submitted [ https://github.com/rpm-software-management/dnf/pull/2065 ]
+
+Signed-off-by: Changqing Li <changqing.li@windriver.com>
+---
+ dnf/lock.py | 12 ++++++++++--
+ 1 file changed, 10 insertions(+), 2 deletions(-)
+
+diff --git a/dnf/lock.py b/dnf/lock.py
+index 6817aac9..5718062a 100644
+--- a/dnf/lock.py
++++ b/dnf/lock.py
+@@ -128,7 +128,11 @@ class ProcessLock(object):
+         self._lock_thread()
+         prev_pid = -1
+         my_pid = os.getpid()
+-        pid = self._try_lock(my_pid)
++        try:
++            pid = self._try_lock(my_pid)
++        except Exception:
++            self._unlock_thread()
++            raise
+         while pid != my_pid:
+             if pid != -1:
+                 if not self.blocking:
+@@ -140,7 +144,11 @@ class ProcessLock(object):
+                     logger.info(msg)
+                     prev_pid = pid
+             time.sleep(1)
+-            pid = self._try_lock(my_pid)
++            try:
++                pid = self._try_lock(my_pid)
++            except Exception:
++                self._unlock_thread()
++                raise
+ 
+     def __exit__(self, *exc_args):
+         if self.count == 1:
+-- 
+2.25.1
+
diff --git a/meta/recipes-devtools/dnf/dnf_4.19.0.bb b/meta/recipes-devtools/dnf/dnf_4.19.0.bb
index 784d7a94b3..184dbea963 100644
--- a/meta/recipes-devtools/dnf/dnf_4.19.0.bb
+++ b/meta/recipes-devtools/dnf/dnf_4.19.0.bb
@@ -15,6 +15,7 @@ SRC_URI = "git://github.com/rpm-software-management/dnf.git;branch=master;protoc
            file://0029-Do-not-set-PYTHON_INSTALL_DIR-by-running-python.patch \
            file://0030-Run-python-scripts-using-env.patch \
            file://0001-set-python-path-for-completion_helper.patch \
+           file://0001-lock.py-fix-Exception-handling.patch \
            "
 
 SRC_URI:append:class-native = "file://0001-dnf-write-the-log-lock-to-root.patch"