meson: Improve RPATH handling

Right now we're unconditionally adding RPATH information to the
installed binaries and libraries, but that's not always desired.

autotools seem to be smart enough to only include that information
when targeting a non-standard prefix, so most distro packages
don't actually contain it; moreover, both Debian and Fedora have
wiki pages encouraging packagers to avoid setting RPATH:

  https://wiki.debian.org/RpathIssue
  https://fedoraproject.org/wiki/RPath_Packaging_Draft

Implement RPATH logic that Does The Right Thing™ in the most
common cases, while still offering users the ability to override
the default behavior if they have specific needs.

Signed-off-by: Andrea Bolognani <abologna@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>

meson.build

@@ -156,6 +156,16 @@ if rc.returncode() == 0
 endif
 
 
+# Add RPATH information when building for a non-standard prefix, or
+# when explicitly requested to do so
+
+if prefix == '/usr' and not get_option('rpath').enabled()
+  libvirt_rpath = ''
+else
+  libvirt_rpath = libdir
+endif
+
+
 # figure out libvirt version strings
 
 arr_version = meson.project_version().split('.')

meson_options.txt

@@ -6,6 +6,7 @@ option('runstatedir', type: 'string', value: '', description: 'State directory f
 option('expensive_tests', type: 'feature', value: 'auto', description: 'set the default for enabling expensive tests (long timeouts), use VIR_TEST_EXPENSIVE to override')
 option('test_coverage', type: 'boolean', value: false, description: 'turn on code coverage instrumentation')
 option('git_werror', type: 'feature', value: 'auto', description: 'use -Werror if building from GIT')
+option('rpath', type: 'feature', value: 'auto', description: 'whether to include rpath information in installed binaries and libraries')
 
 
 # build dependencies options

src/meson.build

@@ -454,7 +454,7 @@ libvirt_qemu_lib = shared_library(
     libvirt_qemu_syms_file,
   ],
   install: true,
-  install_rpath: libdir,
+  install_rpath: libvirt_rpath,
   version: libvirt_lib_version,
   soversion: libvirt_so_version,
 )
@@ -510,7 +510,7 @@ libvirt_lxc_lib = shared_library(
     libvirt_lxc_syms_file,
   ],
   install: true,
-  install_rpath: libdir,
+  install_rpath: libvirt_rpath,
   version: libvirt_lib_version,
   soversion: libvirt_so_version,
 )
@@ -554,7 +554,7 @@ libvirt_admin_lib = shared_library(
     libvirt_admin_syms_file,
   ],
   install: true,
-  install_rpath: libdir,
+  install_rpath: libvirt_rpath,
   version: libvirt_lib_version,
   soversion: libvirt_so_version,
 )
@@ -588,7 +588,7 @@ foreach module : virt_modules
     ],
     install: true,
     install_dir: module.get('install_dir', libdir / 'libvirt' / 'connection-driver'),
-    install_rpath: libdir,
+    install_rpath: libvirt_rpath,
   )
   set_variable('@0@_module'.format(module['name'].underscorify()), mod)
 endforeach
@@ -633,7 +633,7 @@ foreach daemon : virt_daemons
     ],
     install: true,
     install_dir: sbindir,
-    install_rpath: libdir,
+    install_rpath: libvirt_rpath,
   )
 endforeach
 
@@ -661,7 +661,7 @@ foreach helper : virt_helpers
     ],
     install: true,
     install_dir: helper.get('install_dir', libexecdir),
-    install_rpath: libdir,
+    install_rpath: libvirt_rpath,
   )
 endforeach
 

tools/meson.build

@@ -75,7 +75,7 @@ if conf.has('WITH_HOST_VALIDATE')
     ],
     install: true,
     install_dir: bindir,
-    install_rpath: libdir,
+    install_rpath: libvirt_rpath,
   )
 endif
 
@@ -112,7 +112,7 @@ if conf.has('WITH_LOGIN_SHELL')
     ],
     install: true,
     install_dir: libexecdir,
-    install_rpath: libdir,
+    install_rpath: libvirt_rpath,
   )
 
   install_data('virt-login-shell.conf', install_dir: sysconfdir / 'libvirt')
@@ -197,7 +197,7 @@ executable(
   ],
   install: true,
   install_dir: bindir,
-  install_rpath: libdir,
+  install_rpath: libvirt_rpath,
 )
 
 executable(
@@ -219,7 +219,7 @@ executable(
   ],
   install: true,
   install_dir: bindir,
-  install_rpath: libdir,
+  install_rpath: libvirt_rpath,
 )
 
 tools_conf = configuration_data()