GH-46147: [C++] Implement GCS support in Meson

Author: WillAyd

ci/scripts/cpp_build.sh

@@ -145,7 +145,6 @@ if [ "${ARROW_USE_MESON:-OFF}" = "ON" ]; then
     --pkg-config-path="${CONDA_PREFIX}/lib/pkgconfig/" \
     -Dauto_features=enabled \
     -Dfuzzing=disabled \
-    -Dgcs=disabled \
     -Ds3=disabled \
     . \
     ${source_dir}

cpp/src/arrow/meson.build

@@ -409,7 +409,52 @@ if needs_filesystem
     endif
 
     if needs_gcs
-        error('gcs filesystem support is not yet implemented in Meson')
+        arrow_filesystem_srcs += files(
+            'filesystem/gcsfs.cc',
+            'filesystem/gcsfs_internal.cc',
+        )
+
+        gcs_common_dep = dependency(
+            'google_cloud_cpp_common',
+            allow_fallback: false,
+            required: false,
+        )
+        gcs_rest_internal_dep = dependency(
+            'google_cloud_cpp_rest_internal',
+            allow_fallback: false,
+            required: false,
+        )
+        gcs_storage_dep = dependency(
+            'google_cloud_cpp_storage',
+            allow_fallback: false,
+            required: false,
+        )
+
+        if not (gcs_common_dep.found()
+    and gcs_rest_internal_dep.found()
+    and gcs_storage_dep.found()
+)
+            error(
+                '''
+The Arrow Meson configuration requires that google_cloud_cpp_common,
+google_cloud_cpp_rest_internal, and google_cloud_cpp_storage be provided
+by the host system, but these could not be found. Subproject fallback is
+not implemented.
+
+Ensure that you have all of these components installed on your system, or
+disable Arrow gcs support with -Dgcs=disabled.
+            ''',
+            )
+        endif
+
+        gcs_dep = declare_dependency(
+            dependencies: [
+                gcs_common_dep,
+                gcs_rest_internal_dep,
+                gcs_storage_dep,
+            ],
+        )
+        arrow_filesystem_deps += [gcs_dep]
     endif
 
     if needs_hdfs
@@ -622,6 +667,7 @@ if needs_testing
         boost_opt = cmake.subproject_options()
         boost_opt.add_cmake_defines(
             {'BOOST_INCLUDE_LIBRARIES': 'filesystem;system'},
+            {'CMAKE_CXX_FLAGS': '-fPIC'},
         )
         boost_proj = cmake.subproject('boost', options: boost_opt)
         filesystem_dep = boost_proj.dependency('boost_filesystem')

cpp/src/arrow/util/meson.build

@@ -54,7 +54,7 @@ conf_data.set('ARROW_PARQUET', needs_parquet)
 conf_data.set('ARROW_SUBSTRAIT', false)
 conf_data.set('ARROW_AZURE', false)
 conf_data.set('ARROW_ENABLE_THREADING', true)
-conf_data.set('ARROW_GCS', false)
+conf_data.set('ARROW_GCS', needs_gcs)
 conf_data.set('ARROW_HDFS', false)
 conf_data.set('ARROW_S3', false)
 conf_data.set('ARROW_USE_GLOG', false)