tools/nolibc/types: move the FD_* functions to macros in types.h

FD_SET, FD_CLR, FD_ISSET, FD_ZERO are often expected to be macros and
not functions. In addition we already have a file dedicated to such
macros and types used by syscalls, it's types.h, so let's move them
there and turn them to macros. FD_CLR() and FD_ISSET() were missing,
so they were added. FD_ZERO() now deals with its own loop so that it
doesn't rely on memset() that sets one byte at a time.

Cc: David Laight <David.Laight@aculab.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

tools/include/nolibc/nolibc.h

@@ -118,20 +118,6 @@ const char *ltoa(long in)
 
 /* Here come a few helper functions */
 
-static __attribute__((unused))
-void FD_ZERO(fd_set *set)
-{
-	memset(set, 0, sizeof(*set));
-}
-
-static __attribute__((unused))
-void FD_SET(int fd, fd_set *set)
-{
-	if (fd < 0 || fd >= FD_SETSIZE)
-		return;
-	set->fd32[fd / 32] |= 1 << (fd & 31);
-}
-
 /* WARNING, it only deals with the 4096 first majors and 256 first minors */
 static __attribute__((unused))
 dev_t makedev(unsigned int major, unsigned int minor)

tools/include/nolibc/types.h

@@ -75,6 +75,36 @@ typedef struct {
 	uint32_t fd32[FD_SETSIZE / 32];
 } fd_set;
 
+#define FD_CLR(fd, set) do {                                            \
+		fd_set *__set = (set);                                  \
+		int __fd = (fd);                                        \
+		if (__fd >= 0)                                          \
+			__set->fd32[__fd / 32] &= ~(1U << (__fd & 31)); \
+	} while (0)
+
+#define FD_SET(fd, set) do {                                            \
+		fd_set *__set = (set);                                  \
+		int __fd = (fd);                                        \
+		if (__fd >= 0)                                          \
+			__set->fd32[__fd / 32] |= 1U << (__fd & 31);    \
+	} while (0)
+
+#define FD_ISSET(fd, set) ({                                                  \
+		fd_set *__set = (set);                                        \
+		int __fd = (fd);                                              \
+		int __r = 0;                                                  \
+		if (__fd >= 0)                                                \
+			__r = !!(__set->fd32[__fd / 32] & 1U << (__fd & 31)); \
+		__r;                                                          \
+	})
+
+#define FD_ZERO(set) do {                                               \
+		fd_set *__set = (set);                                  \
+		int __idx;                                              \
+		for (__idx = 0; __idx < FD_SETSIZE / 32; __idx ++)      \
+			__set->fd32[__idx] = 0;                         \
+	} while (0)
+
 /* for poll() */
 struct pollfd {
 	int fd;