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From:   Sven Schnelle <svens@linux.ibm.com>
To:     Willy Tarreau <w@1wt.eu>, "Paul E . McKenney" <paulmck@kernel.org>,
        Josh Triplett <josh@joshtriplett.org>
Cc:     Steven Rostedt <rostedt@goodmis.org>,
        Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
        Lai Jiangshan <jiangshanlai@gmail.com>,
        linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org
Subject: [PATCH v3 1/5] nolibc: fix fd_set type
Date:   Tue,  3 Jan 2023 08:19:53 +0100
Message-Id: <20230103071957.222360-2-svens@linux.ibm.com>
In-Reply-To: <20230103071957.222360-1-svens@linux.ibm.com>
References: <20230103071957.222360-1-svens@linux.ibm.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
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The kernel uses unsigned long for the fd_set bitmap,
but nolibc use u32. This works fine on little endian
machines, but fails on big endian. Convert to unsigned
long to fix this.

Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
---
 tools/include/nolibc/types.h | 53 ++++++++++++++++++++----------------
 1 file changed, 30 insertions(+), 23 deletions(-)

diff --git a/tools/include/nolibc/types.h b/tools/include/nolibc/types.h
index 959997034e55..300e0ff1cd58 100644
--- a/tools/include/nolibc/types.h
+++ b/tools/include/nolibc/types.h
@@ -89,39 +89,46 @@
 #define EXIT_SUCCESS 0
 #define EXIT_FAILURE 1
 
+#define FD_SETIDXMASK (8 * sizeof(unsigned long))
+#define FD_SETBITMASK (8 * sizeof(unsigned long)-1)
+
 /* for select() */
 typedef struct {
-	uint32_t fd32[(FD_SETSIZE + 31) / 32];
+	unsigned long fds[(FD_SETSIZE + FD_SETBITMASK) / FD_SETIDXMASK];
 } 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)); \
+#define FD_CLR(fd, set) do {						\
+		fd_set *__set = (set);					\
+		int __fd = (fd);					\
+		if (__fd >= 0)						\
+			__set->fds[__fd / FD_SETIDXMASK] &=		\
+				~(1U << (__fd & FX_SETBITMASK));	\
 	} 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);    \
+#define FD_SET(fd, set) do {						\
+		fd_set *__set = (set);					\
+		int __fd = (fd);					\
+		if (__fd >= 0)						\
+			__set->fds[__fd / FD_SETIDXMASK] |=		\
+				1 << (__fd & FD_SETBITMASK);		\
 	} 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_ISSET(fd, set) ({						\
+			fd_set *__set = (set);				\
+			int __fd = (fd);				\
+		int __r = 0;						\
+		if (__fd >= 0)						\
+			__r = !!(__set->fds[__fd / FD_SETIDXMASK] &	\
+1U << (__fd & FD_SET_BITMASK));						\
+		__r;							\
 	})
 
-#define FD_ZERO(set) do {                                               \
-		fd_set *__set = (set);                                  \
-		int __idx;                                              \
-		for (__idx = 0; __idx < (FD_SETSIZE+31) / 32; __idx ++) \
-			__set->fd32[__idx] = 0;                         \
+#define FD_ZERO(set) do {						\
+		fd_set *__set = (set);					\
+		int __idx;						\
+		int __size = (FD_SETSIZE+FD_SETBITMASK) / FD_SETIDXMASK;\
+		for (__idx = 0; __idx < __size; __idx++)		\
+			__set->fds[__idx] = 0;				\
 	} while (0)
 
 /* for poll() */
-- 
2.34.1