[PATCH v2] configure: add option for virtiofsd

[Misono Tomohiro]

Currently it is unknown whether virtiofsd will be built at
configuration time. It will be automatically built when dependency
is met. Also, required libraries are not clear.

To make this clear, add configure option --{enable,disable}-virtiofsd.
The default is the same as current (enabled if available) like many
other options. When --enable-virtiofsd is given and dependency is not
met, we get:

  ERROR: Problem encountered: virtiofsd requires libcap-ng-devel and 
seccomp-devel
or
  ERROR: Problem encountered: virtiofsd needs tools and vhost-user support

In addition, configuration summary now includes virtiofsd entry:

  build virtiofs daemon: YES/NO

Signed-off-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
---
This patch is based on current master branch

v1 ... 
20201007092913.1524199-1-misono.tomohiro@jp.fujitsu.com/">https://lore.kernel.org/qemu-devel/20201007092913.1524199-1-misono.tomohiro@jp.fujitsu.com/
v1 -> v2: Update to follow the current meson build style

 configure         |  8 +++++++-
 meson.build       |  1 +
 meson_options.txt |  2 ++
 tools/meson.build | 17 +++++++++++++++--
 4 files changed, 25 insertions(+), 3 deletions(-)

diff --git a/configure b/configure
index 28df227db5..2bd8419b1f 100755
--- a/configure
+++ b/configure
@@ -302,6 +302,7 @@ netmap="no"
 sdl="auto"
 sdl_image="auto"
 virtfs=""
+virtiofsd="auto"
 mpath="auto"
 vnc="enabled"
 sparse="auto"
@@ -1004,6 +1005,10 @@ for opt do
   ;;
   --enable-virtfs) virtfs="yes"
   ;;
+  --disable-virtiofsd) virtiofsd="disabled"
+  ;;
+  --enable-virtiofsd) virtiofsd="enabled"
+  ;;
   --disable-mpath) mpath="disabled"
   ;;
   --enable-mpath) mpath="enabled"
@@ -1761,6 +1766,7 @@ disabled with --disable-FEATURE, default is enabled if 
available:
   vnc-png         PNG compression for VNC server
   cocoa           Cocoa UI (Mac OS X only)
   virtfs          VirtFS
+  virtiofsd       build virtiofs daemon (virtiofsd)
   mpath           Multipath persistent reservation passthrough
   xen             xen backend driver support
   xen-pci-passthrough    PCI passthrough support for Xen
@@ -7215,7 +7221,7 @@ NINJA=${ninja:-$PWD/ninjatool} $meson setup \
        -Dxen=$xen -Dxen_pci_passthrough=$xen_pci_passthrough -Dtcg=$tcg \
        -Dcocoa=$cocoa -Dmpath=$mpath -Dsdl=$sdl -Dsdl_image=$sdl_image \
        -Dvnc=$vnc -Dvnc_sasl=$vnc_sasl -Dvnc_jpeg=$vnc_jpeg -Dvnc_png=$vnc_png 
\
-       -Dgettext=$gettext -Dxkbcommon=$xkbcommon -Du2f=$u2f \
+       -Dgettext=$gettext -Dxkbcommon=$xkbcommon -Du2f=$u2f 
-Dvirtiofsd=$virtiofsd \
        -Dcapstone=$capstone -Dslirp=$slirp -Dfdt=$fdt \
         $cross_arg \
         "$PWD" "$source_path"
diff --git a/meson.build b/meson.build
index 17c89c87c6..a087239009 100644
--- a/meson.build
+++ b/meson.build
@@ -1843,6 +1843,7 @@ summary_info += {'Audio drivers':     
config_host['CONFIG_AUDIO_DRIVERS']}
 summary_info += {'Block whitelist (rw)': 
config_host['CONFIG_BDRV_RW_WHITELIST']}
 summary_info += {'Block whitelist (ro)': 
config_host['CONFIG_BDRV_RO_WHITELIST']}
 summary_info += {'VirtFS support':    config_host.has_key('CONFIG_VIRTFS')}
+summary_info += {'build virtiofs daemon': have_virtiofsd}
 summary_info += {'Multipath support': mpathpersist.found()}
 summary_info += {'VNC support':       vnc.found()}
 if vnc.found()
diff --git a/meson_options.txt b/meson_options.txt
index 1d3c94840a..80637ada63 100644
--- a/meson_options.txt
+++ b/meson_options.txt
@@ -48,6 +48,8 @@ option('vnc_sasl', type : 'feature', value : 'auto',
        description: 'SASL authentication for VNC server')
 option('xkbcommon', type : 'feature', value : 'auto',
        description: 'xkbcommon support')
+option('virtiofsd', type: 'feature', value: 'auto',
+       description: 'build virtiofs daemon (virtiofsd)')
 
 option('capstone', type: 'combo', value: 'auto',
        choices: ['disabled', 'enabled', 'auto', 'system', 'internal'],
diff --git a/tools/meson.build b/tools/meson.build
index 513bd2ff4f..76bf84df52 100644
--- a/tools/meson.build
+++ b/tools/meson.build
@@ -1,10 +1,23 @@
-have_virtiofsd = (have_system and
+have_virtiofsd = (targetos == 'linux' and
     have_tools and
-    'CONFIG_LINUX' in config_host and 
     'CONFIG_SECCOMP' in config_host and
     'CONFIG_LIBCAP_NG' in config_host and
     'CONFIG_VHOST_USER' in config_host)
 
+if get_option('virtiofsd').enabled()
+  if not have_virtiofsd
+    if targetos != 'linux'
+      error('virtiofsd requires Linux')
+    elif 'CONFIG_SECCOMP' not in config_host or 'CONFIG_LIBCAP_NG' not in 
config_host
+      error('virtiofsd requires libcap-ng-devel and seccomp-devel')
+    elif not have_tools or 'CONFIG_VHOST_USER' not in config_host
+      error('virtiofsd needs tools and vhost-user support')
+    endif
+  endif
+elif get_option('virtiofsd').disabled() or not have_system
+  have_virtiofsd = false
+endif
+
 if have_virtiofsd
   subdir('virtiofsd')
 endif
-- 
2.25.4