day1: added shim for part 2

Fortune for aoc2021's current commit: Half blessing − 半吉

day1/src/main.c

@@ -3,7 +3,17 @@
 #include <input.h>
 
 extern int part1(uint64_t* restrict);
-extern int part2();
+extern int part2(uint64_t* restrict);
+
+inline static void print_value(int part, uint64_t p)
+{
+#ifdef DEBUG
+	printf("[%d] >>> %lu\n", part, p);
+#else
+	(void)part;
+	printf("%lu\n", p);
+#endif
+}
 
 int main()
 {
@@ -11,14 +21,12 @@ int main()
 #ifdef _PART1
 	uint64_t p1;
 	if( (r = part1(&p1)) ) return r;
-#ifdef DEBUG
-	printf("[1] >>> %lu\n", p1);
-#else
-	printf("%lu\n", p1);
-#endif
+	print_value(1, p1);
 #endif
 #ifdef _PART2
-	if( (r = part2()) ) return r;
+	uint64_t p2;
+	if( (r = part2(&p2)) ) return r;
+	print_value(2, p2);
 #endif
 	return r;
 }

day1/src/p2.c

@@ -0,0 +1,11 @@
+#include <input.h>
+
+#include <tracem/macros.h>
+
+int part2(uint64_t* restrict _res)
+{
+	uint64_t res=0;
+	TODO("unimplemented");
+	*_res = res;
+	return 0;
+}