Merge remote-tracking branch 'origin/pr/634'

* origin/pr/634:
  sys-log: fix dependecies & merge `read_log_backend_feature` into `open_log_backend`
  sys-log: use qubesdb lib directly
  sys-log: backends
  sys-log: use link instead of script
  sys-log: reformat whitespaces
  sys-log: use qubes name checker from qubes-pure
  sys-log: use sanitization from qubes-pure
  sys-log: alpha

Pull request description:

A simple and efficient log sanitizer, ready to work with rsyslog

first step in: QubesOS/qubes-issues/issues/830

requires: QubesOS/qubes-linux-utils/pull/136

Author: marmarek

debian/control

@@ -17,6 +17,7 @@ Build-Depends:
     pkg-config,
     python3,
     python3-setuptools,
+    qubesdb-dev,
     quilt,
     shared-mime-info,
     xserver-xorg-dev,

debian/qubes-core-agent.install

@@ -17,6 +17,7 @@ etc/qubes-rpc/qubes.Filecopy
 etc/qubes-rpc/qubes.GetAppmenus
 etc/qubes-rpc/qubes.GetImageRGBA
 etc/qubes-rpc/qubes.InstallUpdatesGUI
+etc/qubes-rpc/qubes.Log
 etc/qubes-rpc/qubes.OpenInVM
 etc/qubes-rpc/qubes.OpenURL
 etc/qubes-rpc/qubes.PostInstall
@@ -197,6 +198,7 @@ usr/lib/qubes/update-proxy-configs
 usr/lib/qubes/upgrades-installed-check
 usr/lib/qubes/upgrades-status-notify
 usr/lib/qubes/vm-file-editor
+usr/lib/qubes/vm-log
 usr/lib/qubes/xdg-icon
 usr/lib/qubes/set-default-text-editor
 usr/share/glib-2.0/schemas/*

qubes-rpc/.gitignore

@@ -6,4 +6,5 @@ qfile-agent-dvm
 qfile-unpacker
 qopen-in-vm
 vm-file-editor
+vm-log
 tar2qfile

qubes-rpc/Makefile

@@ -17,13 +17,13 @@ LDLIBS := -lqubes-rpc-filecopy -lqubes-pure
 
 .PHONY: all clean install
 
-all:	vm-file-editor qopen-in-vm qfile-agent qfile-unpacker tar2qfile qubes-fs-tree-check bin-qfile-unpacker
+all:	vm-file-editor vm-log qopen-in-vm qfile-agent qfile-unpacker tar2qfile qubes-fs-tree-check bin-qfile-unpacker
 
 ifdef DEVEL_BUILD
 # Ensure that these programs can find their shared libraries,
 # even when installed in e.g. a TemplateBasedVM to somewhere other
 # than /usr.
-vm-file-editor qopen-in-vm qfile-agent qfile-unpacker tar2qfile qubes-fs-tree-check: LDFLAGS += '-Wl,-rpath,$$ORIGIN/../../$$LIB'
+vm-file-editor vm-log qopen-in-vm qfile-agent qfile-unpacker tar2qfile qubes-fs-tree-check: LDFLAGS += '-Wl,-rpath,$$ORIGIN/../../$$LIB'
 # This is installed in /usr/bin, not /usr/lib/qubes, so it needs a different rpath.
 bin-qfile-unpacker: LDFLAGS += '-Wl,-rpath,$$ORIGIN/../$$LIB'
 endif
@@ -33,13 +33,15 @@ bin-qfile-unpacker: qfile-unpacker.o gui-fatal.o
 qubes-fs-tree-check: LDLIBS := -lqubes-pure
 qubes-fs-tree-check: qubes-fs-tree-check.o
 vm-file-editor: vm-file-editor.o
+vm-log: LDLIBS += -lqubesdb
+vm-log: vm-log.o
 qopen-in-vm: qopen-in-vm.o gui-fatal.o
 qfile-agent: qfile-agent.o gui-fatal.o
 qfile-unpacker: qfile-unpacker.o gui-fatal.o
 tar2qfile: tar2qfile.o gui-fatal.o
 
 clean:
-	-$(RM) -- qopen-in-vm qfile-agent qfile-unpacker tar2qfile vm-file-editor qubes-fs-tree-check bin-qfile-unpacker *.o
+	-$(RM) -- qopen-in-vm qfile-agent qfile-unpacker tar2qfile vm-file-editor vm-log qubes-fs-tree-check bin-qfile-unpacker *.o
 
 install:
 	install -d $(DESTDIR)$(BINDIR)
@@ -61,7 +63,7 @@ install:
 		prepare-suspend resize-rootfs \
 		qfile-agent qopen-in-vm qrun-in-vm qubes-sync-clock \
 		tar2qfile vm-file-editor xdg-icon qvm-template-repo-query \
-		qubes-fs-tree-check
+		qubes-fs-tree-check vm-log
 	# Install qfile-unpacker as SUID, because it will fail to receive
 	# files from other vm.
 	install -t $(DESTDIR)$(QUBESLIBDIR) -m 4755 qfile-unpacker
@@ -96,6 +98,7 @@ install:
 		qubes.TemplateSearch \
 		qubes.TemplateDownload
 	$(LN) qubes.VMExec $(DESTDIR)$(QUBESRPCCMDDIR)/qubes.VMExecGUI
+	$(LN) $(QUBESLIBDIR)/vm-log $(DESTDIR)$(QUBESRPCCMDDIR)/qubes.Log
 	$(LN) /dev/tcp/127.0.0.1 $(DESTDIR)$(QUBESRPCCMDDIR)/qubes.ConnectTCP
 	$(LN) /dev/tcp/127.0.0.1/8082 $(DESTDIR)$(QUBESRPCCMDDIR)/qubes.UpdatesProxy
 	for config in *.config; do \