treewide: Leverage sdbus++-gen-meson

This makes us more consistent with other projects instead of writing
meson builds for sdbus++ by hand.

Change-Id: I38b69bc67b6a3d80cda1b508a76e106a50d8ab93
Signed-off-by: Willam A. Kennington III <wak@google.com>
diff --git a/example/gen/meson.build b/example/gen/meson.build
new file mode 100644
index 0000000..2756633
--- /dev/null
+++ b/example/gen/meson.build
@@ -0,0 +1,14 @@
+# Generated file; do not modify.
+sdbuspp_gen_meson_ver = run_command(
+    sdbuspp_gen_meson_prog,
+    '--version',
+).stdout().strip().split('\n')[0]
+
+if sdbuspp_gen_meson_ver != 'sdbus++-gen-meson version 4'
+    warning('Generated meson files from wrong version of sdbus++-gen-meson.')
+    warning(
+        'Expected "sdbus++-gen-meson version 4", got:',
+        sdbuspp_gen_meson_ver
+    )
+endif
+
diff --git a/example/gen/net/meson.build b/example/gen/net/meson.build
new file mode 100644
index 0000000..5ea98c6
--- /dev/null
+++ b/example/gen/net/meson.build
@@ -0,0 +1,2 @@
+# Generated file; do not modify.
+subdir('poettering')
diff --git a/example/gen/net/poettering/Calculator/meson.build b/example/gen/net/poettering/Calculator/meson.build
new file mode 100644
index 0000000..6b469e6
--- /dev/null
+++ b/example/gen/net/poettering/Calculator/meson.build
@@ -0,0 +1,15 @@
+# Generated file; do not modify.
+generated_sources += custom_target(
+    'net/poettering/Calculator__cpp'.underscorify(),
+    input: [ '../../../../yaml/net/poettering/Calculator.interface.yaml',  ],
+    output: [ 'error.cpp', 'error.hpp', 'server.cpp', 'server.hpp', 'client.hpp',  ],
+    depend_files: sdbusplusplus_depfiles,
+    command: [
+        sdbuspp_gen_meson_prog, '--command', 'cpp',
+        '--output', meson.current_build_dir(),
+        '--tool', sdbusplusplus_prog,
+        '--directory', meson.current_source_dir() / '../../../../yaml',
+        'net/poettering/Calculator',
+    ],
+)
+
diff --git a/example/gen/net/poettering/meson.build b/example/gen/net/poettering/meson.build
new file mode 100644
index 0000000..a91287e
--- /dev/null
+++ b/example/gen/net/poettering/meson.build
@@ -0,0 +1,16 @@
+# Generated file; do not modify.
+subdir('Calculator')
+generated_others += custom_target(
+    'net/poettering/Calculator__markdown'.underscorify(),
+    input: [ '../../../yaml/net/poettering/Calculator.interface.yaml',  ],
+    output: [ 'Calculator.md' ],
+    depend_files: sdbusplusplus_depfiles,
+    command: [
+        sdbuspp_gen_meson_prog, '--command', 'markdown',
+        '--output', meson.current_build_dir(),
+        '--tool', sdbusplusplus_prog,
+        '--directory', meson.current_source_dir() / '../../../yaml',
+        'net/poettering/Calculator',
+    ],
+)
+
diff --git a/example/gen/regenerate-meson b/example/gen/regenerate-meson
new file mode 100755
index 0000000..235d551
--- /dev/null
+++ b/example/gen/regenerate-meson
@@ -0,0 +1,4 @@
+#!/bin/bash
+cd "$(dirname "$0")" || exit
+export PATH="${PWD}/../../tools:${PATH}"
+exec sdbus++-gen-meson --command meson --directory ../yaml --output .
diff --git a/example/gen/run-ci b/example/gen/run-ci
new file mode 100755
index 0000000..0a248a0
--- /dev/null
+++ b/example/gen/run-ci
@@ -0,0 +1,15 @@
+#!/bin/bash
+cd "$(dirname "$0")" || exit
+./regenerate-meson || exit
+rc=0
+git --no-pager diff --exit-code -- . || rc=$?
+untracked="$(git ls-files --others --exclude-standard -- .)" || rc=$?
+if [[ -n "${untracked}" ]]; then
+  echo "Untracked files:" >&2
+  echo "${untracked}" >&2
+  rc=1
+fi
+if (( rc != 0 )); then
+  echo "Generated meson files differ from expected values" >&2
+  exit 1
+fi
diff --git a/example/meson.build b/example/meson.build
index b338dc1..17fd569 100644
--- a/example/meson.build
+++ b/example/meson.build
@@ -44,10 +44,16 @@
     dependencies: asio_dep,
 )
 
-subdir('net/poettering/Calculator')
+generated_sources = []
+generated_others = []
+subdir('gen')
+subdir('gen/net')
+
 executable(
     'calculator-server',
     'calculator-server.cpp',
-    calculator_sources,
+    generated_sources,
+    implicit_include_directories: false,
+    include_directories: include_directories('gen'),
     dependencies: sdbusplus_dep,
 )
diff --git a/example/net/poettering/Calculator/meson.build b/example/net/poettering/Calculator/meson.build
deleted file mode 100644
index f77fc5b..0000000
--- a/example/net/poettering/Calculator/meson.build
+++ /dev/null
@@ -1,29 +0,0 @@
-calculator_sources = []
-
-calculator_sources += custom_target(
-    'Calculator__cpp',
-    input: '../Calculator.interface.yaml',
-    output: [ 'server.cpp', 'server.hpp', 'client.hpp' ],
-    depend_files: sdbusplusplus_depfiles,
-    command: [
-        sdbuspp_gen_meson_prog, '--command', 'cpp',
-        '--output', meson.current_build_dir(),
-        '--tool', sdbusplusplus_prog,
-        '--directory', meson.current_source_dir() / '../../..',
-        'net/poettering/Calculator',
-    ],
-)
-
-calculator_sources += custom_target(
-    'Calculator__errors',
-    input: '../Calculator.errors.yaml',
-    output: [ 'error.cpp', 'error.hpp' ],
-    depend_files: sdbusplusplus_depfiles,
-    command: [
-        sdbuspp_gen_meson_prog, '--command', 'cpp',
-        '--output', meson.current_build_dir(),
-        '--tool', sdbusplusplus_prog,
-        '--directory', meson.current_source_dir() / '../../..',
-        'net/poettering/Calculator',
-    ],
-)
diff --git a/example/net/poettering/Calculator.errors.yaml b/example/yaml/net/poettering/Calculator.errors.yaml
similarity index 100%
rename from example/net/poettering/Calculator.errors.yaml
rename to example/yaml/net/poettering/Calculator.errors.yaml
diff --git a/example/net/poettering/Calculator.interface.yaml b/example/yaml/net/poettering/Calculator.interface.yaml
similarity index 100%
rename from example/net/poettering/Calculator.interface.yaml
rename to example/yaml/net/poettering/Calculator.interface.yaml