feat: add Server header

Makefile

@@ -1,6 +1,8 @@
 # https://spin.atomicobject.com/2016/08/26/makefile-c-projects/ was a great
 # base for this Makefile
 
+VERSION := 0.1.0
+
 BIN_FILENAME ?= lander
 
 BUILD_DIR ?= build
@@ -34,7 +36,7 @@ INC_FLAGS := $(addprefix -I,$(INC_DIRS))
 # -MP: generate a dummy target for every header file (according to the  docs it
 #  prevents some errors when removing header files)
 CFLAGS ?= -MMD -MP -g
-INTERNALCFLAGS := $(INC_FLAGS) $(CFLAGS) -Wall -Wextra
+INTERNALCFLAGS := $(INC_FLAGS) $(CFLAGS) -Wall -Wextra -DLANDER_VERSION=\"$(VERSION)\"
 
 .PHONY: all
 all: bin

src/http_loop/http_loop_res.c

@@ -6,6 +6,7 @@
 #define MIN(x, y) (((x) < (y)) ? (x) : (y))
 
 static const char *http_response_format = "HTTP/1.1 %i %s\n"
+                                          "Server: lander/" LANDER_VERSION "\n"
                                           "Content-Length: %lu\n\n";
 
 void http_loop_init_header(http_response *res) {