add bit fuckery

Makefile

@@ -1,7 +1,7 @@
 CFLAGS=-std=c99 -Wall -g -O2
 INDENTOPTS=-kr --no-tabs --braces-on-func-def-line --indent-level2
 
-TARGETS=approximate-pi linked-list mandelbrot mandelbrot.bmp threads circular-buffer structs
+TARGETS=approximate-pi linked-list mandelbrot mandelbrot.bmp threads circular-buffer structs ncurses-pong bit-fuckery bit-fuckery2
 
 .PHONY: all
 all: $(TARGETS)
@@ -22,3 +22,6 @@ mandelbrot.bmp: mandelbrot
 
 threads: threads.c
 	$(CC) $(CFLAGS) -o $@ $< -pthread
+
+ncurses-pong: ncurses-pong.c
+	$(CC) $(CFLAGS) -o $@ $< -lncurses

bit-fuckery.c

@@ -0,0 +1,33 @@
+#include <assert.h>
+
+int main() {
+  int foo;
+
+  foo = 42;
+
+  /* Delete bit 5 */
+  foo &= ~(1 << 5);
+  assert(foo == 10);
+  foo &= ~(1 << 5);
+  assert(foo == 10);
+
+  /* Set bit 5 again */
+  foo |= (1 << 5);
+  assert(foo == 42);
+  foo |= (1 << 5);
+  assert(foo == 42);
+
+  /* Set bit 0 */
+  foo |= (1 << 0);
+  assert(foo == 43);
+
+  /* Delete bit 0 */
+  foo &= ~(1 << 0);
+  assert(foo == 42);
+
+  /* Toggle bit 5 */
+  foo ^= (1 << 5);
+  assert(foo == 10);
+  foo ^= (1 << 5);
+  assert(foo == 42);
+}

bit-fuckery2.c

@@ -0,0 +1,37 @@
+#include <assert.h>
+
+#define BIT_DEL(x, n)    ((x) &= ~(1<<(n)))
+#define BIT_SET(x, n)    ((x) |=  (1<<(n)))
+#define BIT_TOGGLE(x, n) ((x) ^=  (1<<(n)))
+
+int main() {
+  int foo;
+
+  foo = 42;
+
+  /* Delete bit 5 */
+  BIT_DEL(foo, 5);
+  assert(foo == 10);
+  BIT_DEL(foo, 5);
+  assert(foo == 10);
+
+  /* Set bit 5 again */
+  BIT_SET(foo, 5);
+  assert(foo == 42);
+  BIT_SET(foo, 5);
+  assert(foo == 42);
+
+  /* Set bit 0 */
+  BIT_SET(foo, 0);
+  assert(foo == 43);
+
+  /* Delete bit 0 */
+  BIT_DEL(foo, 0);
+  assert(foo == 42);
+
+  /* Toggle bit 5 */
+  BIT_TOGGLE(foo, 5);
+  assert(foo == 10);
+  BIT_TOGGLE(foo, 5);
+  assert(foo == 42);
+}