WIP

Makefile

@@ -8,7 +8,8 @@ SRCS = src/quack_heap_scan.cpp \
 			src/quack_hooks.cpp \
 			src/quack_select.cpp \
 			src/quack_types.cpp \
-			src/quack.cpp
+			src/quack.cpp \
+			src/scanner.cpp
 
 OBJS = $(subst .cpp,.o, $(SRCS))
 
@@ -21,15 +22,17 @@ PG_LIB := $(shell $(PG_CONFIG) --pkglibdir)
 INCLUDEDIR := ${shell $(PG_CONFIG) --includedir}
 INCLUDEDIR_SERVER := ${shell $(PG_CONFIG) --includedir-server}
 
+HEADERS := include/quack/scanner.hpp $(wildcard third_party/duckdb/src/include/*/*/*/*/*/*)
+
 DEBUG_FLAGS = -g -O0 -fsanitize=address
-override PG_CPPFLAGS += -Iinclude -Ithird_party/duckdb/src/include -std=c++17
+override PG_CPPFLAGS += -Iinclude -Ithird_party/duckdb/src/include -std=c++17 -rdynamic
 
 SHLIB_LINK += -Wl,-rpath,$(PG_LIB)/ -lpq -L$(PG_LIB) -lduckdb -Lthird_party/duckdb/build/debug/src -lstdc++
 
-COMPILE.cc.bc = $(CXX) -Wno-ignored-attributes -Wno-register $(BITCODE_CXXFLAGS) $(CXXFLAGS) $(PG_CPPFLAGS) -I$(INCLUDEDIR_SERVER) -emit-llvm -c
+COMPILE.cpp.bc = $(CXX) -Wno-ignored-attributes -Wno-register $(BITCODE_CXXFLAGS) $(CXXFLAGS) $(PG_CPPFLAGS) -I$(INCLUDEDIR_SERVER) -emit-llvm -c
 
 %.bc : %.cpp
-	$(COMPILE.cc.bc) $(SHLIB_LINK) $(PG_CPPFLAGS) -I$(INCLUDE_SERVER) -o $@ $<
+	$(COMPILE.cpp.bc) $(SHLIB_LINK) $(PG_CPPFLAGS) -I$(INCLUDE_SERVER) -o $@ $<
 
 # determine the name of the duckdb library that is built
 UNAME_S := $(shell uname -s)
@@ -40,12 +43,15 @@ ifeq ($(UNAME_S),Linux)
 	DUCKDB_LIB = libduckdb.so
 endif
 
-all: duckdb $(OBJS)
+all: duckdb $(OBJS) heap.so
 
 include $(PGXS)
 
 duckdb: third_party/duckdb third_party/duckdb/build/debug/src/$(DUCKDB_LIB)
 
+heap.so:
+	$(CXX) $(PG_CPPFLAGS) $(CPPFLAGS)  -Wl,-rpath,$(PG_LIB)/ -std=c++17 -shared src/scanner/heap.cpp -undefined dynamic_lookup -o heap.so
+
 third_party/duckdb:
 	git submodule update --init --recursive
 
@@ -58,8 +64,19 @@ install_duckdb:
 clean_duckdb:
 	rm -rf third_party/duckdb/build
 
-install: install_duckdb
-clean: clean_duckdb
+install_heap_scanner:
+	$(install_bin) -m 755 heap.so $(DESTDIR)$(PG_LIB)
+
+install: install_duckdb install_heap_scanner
+
+clean_heap_so:
+	rm -f heap.so
+
+clean_depend:
+	rm -f .depend
+
+clean: clean_duckdb clean_heap_so clean_depend
+
 
 lintcheck:
 	clang-tidy $(SRCS) -- -I$(INCLUDEDIR) -I$(INCLUDEDIR_SERVER) -Iinclude $(CPPFLAGS) -std=c++17

include/quack/quack.h

@@ -1,7 +1,12 @@
 #pragma once
 
+#include <string>
+
 // quack.c
 extern "C" void _PG_init(void);
 
 // quack_hooks.c
-extern void quack_init_hooks(void);
+extern void quack_init_hooks(void);
+
+// scanner.cpp
+void load_scanner(std::string name);

include/quack/scanner.hpp

@@ -0,0 +1,28 @@
+#pragma once
+
+extern "C" {
+#include "postgres.h"
+
+#include "utils/relcache.h"
+}
+
+#include <string>
+#include <vector>
+
+class Scanner {
+public:
+	static Scanner *SetupScanner(Relation relation);
+	virtual ~Scanner() = 0;
+	virtual std::vector<Datum> GetNextChunk(uint32 column_id) = 0;
+	virtual std::vector<Oid> GetTypes() = 0;
+	virtual uint32 GetColumnCount() = 0;
+	virtual uint64 GetCurrentRow(uint32 column_id) = 0;
+	virtual std::string GetTableName() = 0;
+
+	Relation relation;
+};
+
+extern "C" void RegisterScanner(char *, void *);
+
+/* Registration function for loaded scanners. */
+extern "C" void ScannerInit();

src/quack.cpp

@@ -6,6 +6,8 @@ extern "C" {
 
 #include "quack/quack.h"
 
+#include "quack/scanner.hpp"
+
 static void quack_init_guc(void);
 
 extern "C" {
@@ -22,5 +24,6 @@ _PG_init(void) {
 /* clang-format off */
 static void
 quack_init_guc(void) {
+	load_scanner("heap");
 
 }

src/scanner.cpp

@@ -0,0 +1,48 @@
+#include <dlfcn.h>
+
+#include <string>
+#include <unordered_map>
+
+extern "C" {
+#include "postgres.h"
+
+#include "miscadmin.h"
+}
+
+#include "quack/scanner.hpp"
+
+std::unordered_map<std::string, Scanner *(*)(Relation)> scanners;
+
+extern "C" void
+RegisterScanner(char *name, void *ptr) {
+	Scanner *(*scanner)(Relation) = (Scanner * (*)(Relation)) ptr;
+	if (scanners[name] != nullptr) {
+		elog(WARNING, "Registering scanner %s, which already exists.", name);
+	}
+
+	scanners[name] = scanner;
+}
+
+void
+load_scanner(std::string name) {
+	std::string path = std::string(pkglib_path) + "/" + name + ".so";
+	void *shared_obj = dlopen(path.c_str(), RTLD_NOW);
+
+	if (shared_obj == nullptr) {
+		elog(WARNING, "Unable to read scanner %s: %s", name.c_str(), dlerror());
+		elog(WARNING, "Path: %s", path.c_str());
+
+		return;
+	}
+
+	void (*init_scanner)(void) = (void (*)(void))dlsym(shared_obj, "ScannerInit");
+
+	if (init_scanner == nullptr) {
+		elog(WARNING, "Unable to find ScannerInit in scanner %s", name.c_str());
+
+		return;
+	}
+
+	init_scanner();
+	elog(DEBUG5, "Scanner %s initialized", name.c_str());
+}

src/scanner/heap.cpp

@@ -0,0 +1,13 @@
+#include "quack/scanner.hpp"
+
+extern "C" {
+#include "postgres.h"
+}
+
+#include <string>
+
+void
+ScannerInit() {
+	elog(WARNING, "registering heap");
+	RegisterScanner((char *)"heap", nullptr);
+}