Add diskquota support for Apache Cloudberry

Integrate diskquota extension into Apache Cloudberry build system and
adapt the codebase for Cloudberry 2.0+ (PostgreSQL 14 based).

Main changes:

Build system integration:
* Add new Makefile for building with Cloudberry source tree
    ```
    make
    make install
    make installcheck
    make clean
    ```
* Update gpcontrib/Makefile to include diskquota in build and installcheck
* Simplify CMakeLists.txt by removing GP6 version conditionals
* Add PG_SRC_DIR availability check for isolation2 tests

Code modernization (remove GP6 compatibility code):
* Remove GP_VERSION_NUM < 70000 conditionals throughout codebase
* Replace deprecated APIs:
    heap_open -> table_open,
    heap_beginscan_catalog -> table_beginscan_catalog,
    heap_endscan -> table_endscan, etc.
* Replace init_ps_display() with set_ps_display() for process status
* Replace StrNCpy() with snprintf() for safer string handling
* Remove WaitForBackgroundWorkerShutdown() polyfill (now in core)
* Remove MemoryAccounting_Reset() calls (removed in GP7+)
* Update tuple descriptor attribute access from pointer to direct access

Documentation:
* Rewrite README.md for Apache Cloudberry with updated build instructions

Other improvements:
* Update extension comment to be more descriptive
* Ensure postgres.h is included first in all source files

CI:
* add ic-diskquota to `build-cloudberry.yml` workflow
* For `build-deb-cloudberry.yml`, the installation and configure prefix
  are not consisent, which results in the test error. Will add
  ic-diskquota test back once updating the deb workflow.

See: https://lists.apache.org/thread/1zd80r1hvpwwh5fjd5yqgcc7sr4f27qr

Author: tuhaihe

.github/workflows/build-cloudberry.yml

@@ -314,6 +314,10 @@ jobs:
                                "gpcontrib/gp_toolkit:installcheck",
                                "gpcontrib/gp_exttable_fdw:installcheck"]
               },
+              {"test":"ic-diskquota",
+               "make_configs":["gpcontrib/diskquota:installcheck"],
+               "shared_preload_libraries":"diskquota-2.3"
+              },
               {"test":"ic-fixme",
                "make_configs":["src/test/regress:installcheck-fixme"],
                "enable_core_check":false
@@ -1379,7 +1383,15 @@ jobs:
 
           {
             chmod +x "${SRC_DIR}"/devops/build/automation/cloudberry/scripts/create-cloudberry-demo-cluster.sh
-            if ! time su - gpadmin -c "cd ${SRC_DIR} && NUM_PRIMARY_MIRROR_PAIRS='${{ matrix.num_primary_mirror_pairs }}' SRC_DIR=${SRC_DIR} ${SRC_DIR}/devops/build/automation/cloudberry/scripts/create-cloudberry-demo-cluster.sh"; then
+
+            # Build BLDWRAP_POSTGRES_CONF_ADDONS for shared_preload_libraries if specified
+            EXTRA_CONF=""
+            if [[ -n "${{ matrix.shared_preload_libraries }}" ]]; then
+              EXTRA_CONF="shared_preload_libraries='${{ matrix.shared_preload_libraries }}'"
+              echo "Adding shared_preload_libraries: ${{ matrix.shared_preload_libraries }}"
+            fi
+
+            if ! time su - gpadmin -c "cd ${SRC_DIR} && NUM_PRIMARY_MIRROR_PAIRS='${{ matrix.num_primary_mirror_pairs }}' BLDWRAP_POSTGRES_CONF_ADDONS=\"${EXTRA_CONF}\" SRC_DIR=${SRC_DIR} ${SRC_DIR}/devops/build/automation/cloudberry/scripts/create-cloudberry-demo-cluster.sh"; then
               echo "::error::Demo cluster creation failed"
               exit 1
             fi

.github/workflows/build-deb-cloudberry.yml

@@ -1322,7 +1322,15 @@ jobs:
 
           {
             chmod +x "${SRC_DIR}"/devops/build/automation/cloudberry/scripts/create-cloudberry-demo-cluster.sh
-            if ! time su - gpadmin -c "cd ${SRC_DIR} && NUM_PRIMARY_MIRROR_PAIRS='${{ matrix.num_primary_mirror_pairs }}' SRC_DIR=${SRC_DIR} ${SRC_DIR}/devops/build/automation/cloudberry/scripts/create-cloudberry-demo-cluster.sh"; then
+
+            # Build BLDWRAP_POSTGRES_CONF_ADDONS for shared_preload_libraries if specified
+            EXTRA_CONF=""
+            if [[ -n "${{ matrix.shared_preload_libraries }}" ]]; then
+              EXTRA_CONF="shared_preload_libraries='${{ matrix.shared_preload_libraries }}'"
+              echo "Adding shared_preload_libraries: ${{ matrix.shared_preload_libraries }}"
+            fi
+
+            if ! time su - gpadmin -c "cd ${SRC_DIR} && NUM_PRIMARY_MIRROR_PAIRS='${{ matrix.num_primary_mirror_pairs }}' BLDWRAP_POSTGRES_CONF_ADDONS=\"${EXTRA_CONF}\" SRC_DIR=${SRC_DIR} ${SRC_DIR}/devops/build/automation/cloudberry/scripts/create-cloudberry-demo-cluster.sh"; then
               echo "::error::Demo cluster creation failed"
               exit 1
             fi

gpcontrib/Makefile

@@ -22,15 +22,17 @@ ifeq "$(enable_debug_extensions)" "yes"
                gp_legacy_string_agg \
                gp_replica_check \
                gp_toolkit \
-               pg_hint_plan
+               pg_hint_plan \
+               diskquota
 else
 	recurse_targets = gp_sparse_vector \
 	       gp_distribution_policy \
                gp_internal_tools \
                gp_legacy_string_agg \
                gp_exttable_fdw \
                gp_toolkit \
-               pg_hint_plan
+               pg_hint_plan \
+               diskquota
 endif
 
 ifeq "$(with_zstd)" "yes"
@@ -97,3 +99,4 @@ installcheck:
 	$(MAKE) -C gp_sparse_vector installcheck
 	$(MAKE) -C gp_toolkit installcheck
 	$(MAKE) -C gp_exttable_fdw installcheck
+	$(MAKE) -C diskquota installcheck

gpcontrib/diskquota/CMakeLists.txt

@@ -22,6 +22,10 @@ include(${CMAKE_CURRENT_SOURCE_DIR}/cmake/Gpdb.cmake)
 # set include directories for all sub-projects
 include_directories(${PG_INCLUDE_DIR_SERVER})
 include_directories(${PG_INCLUDE_DIR}) # for libpq
+# For in-tree builds, libpq headers are in a separate directory
+if(PG_INCLUDE_DIR_LIBPQ)
+    include_directories(${PG_INCLUDE_DIR_LIBPQ})
+endif()
 # Overwrite the default build type flags set by cmake.
 # We don't want the '-O3 -DNDEBUG' from cmake. Instead, those will be set by the CFLAGS from pg_config.
 # And, the good news is, GPDB release always have '-g'.
@@ -85,9 +89,7 @@ set_target_properties(
              C_STANDARD 99
              LINKER_LANGUAGE "C")
 
-if (${GP_MAJOR_VERSION} STRGREATER_EQUAL "7")
-  TARGET_LINK_LIBRARIES(diskquota ${PG_LIB_DIR}/libpq.so)
-endif()
+TARGET_LINK_LIBRARIES(diskquota ${PG_LIB_DIR}/libpq.so)
 
 # packing part, move to a separate file if this part is too large
 include(${CMAKE_CURRENT_SOURCE_DIR}/cmake/Distro.cmake)

gpcontrib/diskquota/Makefile

@@ -0,0 +1,76 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+#
+# Makefile for diskquota extension
+#
+# This Makefile wraps the CMake build system for integration with
+# the Cloudberry build process.
+#
+# Usage:
+#   make                    # build the extension
+#   make install            # install the extension
+#   make installcheck       # run regression tests
+#   make clean              # clean build artifacts
+
+ifdef USE_PGXS
+# Standalone build: pg_config must be in PATH
+PG_CONFIG_ABS := $(shell which pg_config)
+PG_PREFIX := $(shell $(PG_CONFIG_ABS) --prefix)
+CMAKE_OPTS := -DPG_CONFIG=$(PG_CONFIG_ABS)
+else
+# In-tree build
+subdir = gpcontrib/diskquota
+top_builddir = ../..
+include $(top_builddir)/src/Makefile.global
+# Get absolute source directory path
+PG_SRC_DIR_ABS := $(shell cd $(top_builddir) && pwd)
+PG_CONFIG_ABS := $(PG_SRC_DIR_ABS)/src/bin/pg_config/pg_config
+PG_PREFIX := $(prefix)
+# Pass PG_SRC_DIR to CMake so it doesn't try to derive it from pg_config
+CMAKE_OPTS := -DPG_CONFIG=$(PG_CONFIG_ABS) -DPG_SRC_DIR=$(PG_SRC_DIR_ABS)
+endif
+
+.PHONY: all
+all: build
+
+.PHONY: build
+build:
+	@echo "Building diskquota with CMake..."
+	@if [ ! -f build/Makefile ]; then \
+		mkdir -p build && \
+		cd build && \
+		cmake $(CMAKE_OPTS) -DCMAKE_INSTALL_PREFIX=$(DESTDIR)$(PG_PREFIX) .. ; \
+	fi
+	cd build && $(MAKE)
+
+.PHONY: install
+install: build
+	cd build && $(MAKE) install
+
+.PHONY: installcheck
+installcheck:
+	@echo "Running diskquota regression tests..."
+	@if [ ! -f build/Makefile ]; then \
+		mkdir -p build && \
+		cd build && \
+		cmake $(CMAKE_OPTS) -DCMAKE_INSTALL_PREFIX=$(DESTDIR)$(PG_PREFIX) .. ; \
+	fi
+	cd build && $(MAKE) installcheck
+
+.PHONY: clean
+clean:
+	rm -rf build