Fix asan, add tsan and ubsan

.gitignore

@@ -1,2 +1,3 @@
 *.a
 *.o
+*.so

Makefile

@@ -1,7 +1,9 @@
 FIRE_CXX ?= clang++
-FIRE_CXXFLAGS ?= -O3 -std=gnu++2a -Wall -Werror
+FIRE_CXXFLAGS ?= -O3 -std=gnu++2a -Wall -Werror -Wextra -fPIE -fPIC -fstack-protector-strong -fsanitize=safe-stack -fsanitize=safe-stack
+FIRE_LDFLAGS ?= -fuse-ld=gold -flto -Wl,-z,relro -Wl,-z,now
+FIRE_LDLIBS ?= -lglog
 
-all: firebuf.a firebuf.o
+all: firebuf.a firebuf.o firebuf.so
 
 objects = stream_buffer.o buffer.o
 
@@ -9,14 +11,25 @@ firebuf.a: $(objects)
 	ar rcs $@ $^
 
 firebuf.o: $(objects)
-	ld --relocatable --output=$@ $+
+	gold -z relro -z now -r --output=$@ $+
+
+firebuf.so: $(objects)
+	$(FIRE_CXX) $(FIRE_CXXFLAGS) $(FIRE_LDFLAGS) -shared -o $@ $+ $(FIRE_LDFLIBS)
 
 %.o: %.cc *.h Makefile
 	$(FIRE_CXX) $(FIRE_CXXFLAGS) -c -o $@ $<
 
 clean:
-	rm --force *.o *.a
+	rm --force *.so *.o *.a
 
 asan:
 	$(MAKE) clean
-	FIRE_CXXFLAGS="-O1 -g -fsanitize=address -fno-omit-frame-pointer -std=gnu++2a -Wall -Werror" $(MAKE) all
+	FIRE_CXXFLAGS="-O1 -g -fsanitize=address -fno-omit-frame-pointer -std=gnu++2a -fPIE -fPIC" $(MAKE) all
+
+tsan:
+	$(MAKE) clean
+	FIRE_CXXFLAGS="-O1 -g -fsanitize=thread -std=gnu++2a -fPIE -fPIC" $(MAKE) all
+
+ubsan:
+	$(MAKE) clean
+	FIRE_CXXFLAGS="-O1 -g -fsanitize=undefined -std=gnu++2a -fPIE -fPIC" $(MAKE) all

stream_buffer.cc

@@ -7,6 +7,10 @@ StreamBuffer::StreamBuffer(int sock, size_t size)
 		  sock_(sock) {}
 
 bool StreamBuffer::Refill() {
+	if (WriteMaxLen() == 0) {
+		LOG(ERROR) << "buffer full";
+		return false;
+	}
 	auto read_len = read(sock_, WritePtr(), WriteMaxLen());
 	if (read_len == -1) {
 		if (errno == EINTR) {