Add comprehensive DNS cache tests in new dns_cache.c file

Makefile

@@ -48,8 +48,12 @@ LIBGWDNS_TEST_TARGET = $(GWPROXY_DIR)/tests/dns.t
 LIBGWDNS_TEST_CC_SOURCES = $(GWPROXY_DIR)/tests/dns.c
 LIBGWDNS_TEST_OBJECTS = $(LIBGWDNS_TEST_CC_SOURCES:%.c=%.c.o)
 
-ALL_TEST_TARGETS = $(LIBGWDNS_TEST_TARGET) $(LIBGWPSOCKS5_TEST_TARGET)
-ALL_OBJECTS = $(GWPROXY_OBJECTS) $(LIBGWPSOCKS5_OBJECTS) $(LIBGWDNS_OBJECTS) $(LIBGWDNS_TEST_OBJECTS) $(LIBGWPSOCKS5_TEST_OBJECTS)
+LIBGWDNS_CACHE_TEST_TARGET = $(GWPROXY_DIR)/tests/dns_cache.t
+LIBGWDNS_CACHE_TEST_CC_SOURCES = $(GWPROXY_DIR)/tests/dns_cache.c
+LIBGWDNS_CACHE_TEST_OBJECTS = $(LIBGWDNS_CACHE_TEST_CC_SOURCES:%.c=%.c.o)
+
+ALL_TEST_TARGETS = $(LIBGWDNS_TEST_TARGET) $(LIBGWDNS_CACHE_TEST_TARGET) $(LIBGWPSOCKS5_TEST_TARGET)
+ALL_OBJECTS = $(GWPROXY_OBJECTS) $(LIBGWPSOCKS5_OBJECTS) $(LIBGWDNS_OBJECTS) $(LIBGWDNS_TEST_OBJECTS) $(LIBGWDNS_CACHE_TEST_OBJECTS) $(LIBGWPSOCKS5_TEST_OBJECTS)
 ALL_TARGETS = $(GWPROXY_TARGET) $(LIBGWPSOCKS5_TARGET) $(LIBGWDNS_TARGET) $(ALL_TEST_TARGETS)
 ALL_DEPFILES = $(ALL_OBJECTS:.o=.o.d)
 
@@ -72,6 +76,9 @@ $(LIBGWDNS_TARGET): $(LIBGWDNS_OBJECTS)
 $(LIBGWDNS_TEST_TARGET): $(LIBGWDNS_TEST_OBJECTS) $(LIBGWDNS_TARGET)
 	$(CC) $(LDFLAGS) -o $@ $^ $(LIBS)
 
+$(LIBGWDNS_CACHE_TEST_TARGET): $(LIBGWDNS_CACHE_TEST_OBJECTS) $(LIBGWDNS_TARGET)
+	$(CC) $(LDFLAGS) -o $@ $^ $(LIBS)
+
 %.c.o: %.c
 	$(CC) $(CFLAGS) $(DEPFLAGS) -c $< -o $@
 
@@ -83,10 +90,12 @@ clean:
 	rm -f $(TO_BE_REMOVED)
 
 IE=LD_LIBRARY_PATH=$(LD_LIBRARY_PATH):$(shell pwd)
-test: $(LIBGWDNS_TEST_TARGET) $(LIBGWPSOCKS5_TEST_TARGET)
+test: $(LIBGWDNS_TEST_TARGET) $(LIBGWDNS_CACHE_TEST_TARGET) $(LIBGWPSOCKS5_TEST_TARGET)
 	@echo "Running tests...";
 	@echo "Testing libgwdns...";
 	@$(IE) ./$(LIBGWDNS_TEST_TARGET);
+	@echo "Testing libgwdns cache...";
+	@$(IE) ./$(LIBGWDNS_CACHE_TEST_TARGET);
 	@echo "Testing libgwpsocks5...";
 	@$(IE) ./$(LIBGWPSOCKS5_TEST_TARGET);
 	@echo "Tests completed successfully.";

src/gwproxy/dns.c

@@ -490,7 +490,7 @@ static void process_queue_entry(struct gwp_dns_ctx *ctx)
 	 * clone() for each entry if we can process them in the current
 	 * thread.
 	 */
-	if ((ctx->nr_entries + 16) > ctx->nr_sleeping)
+	if (ctx->nr_entries > (ctx->nr_sleeping + 16))
 		process_queue_entry_batch(ctx);
 	else
 		process_queue_entry_single(ctx);