tty: tty_buffer: switch insert functions to size_t

All the functions accept size_t as a size argument. They finally return
the same size (or less). It is quite unexpected that they return a
signed value and can confuse users to check for negative values.

Instead, return the same size_t as accepted to make clear we return
values >= 0, where zero in fact means failure.

Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20230816105530.3335-6-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/tty_buffer.c b/drivers/tty/tty_buffer.c
index c101b4ab737e54bf305fed9564d7b683b645b478..598891e53031a33a7b7beee2a3edd87bbf44dbde 100644 (file)
--- a/drivers/tty/tty_buffer.c
+++ b/drivers/tty/tty_buffer.c
@@ -303,16 +303,16 @@ int tty_buffer_request_room(struct tty_port *port, size_t size)
 }
 EXPORT_SYMBOL_GPL(tty_buffer_request_room);
 
-int __tty_insert_flip_string_flags(struct tty_port *port, const u8 *chars,
-                                  const u8 *flags, bool mutable_flags,
-                                  size_t size)
+size_t __tty_insert_flip_string_flags(struct tty_port *port, const u8 *chars,
+                                     const u8 *flags, bool mutable_flags,
+                                     size_t size)
 {
        bool need_flags = mutable_flags || flags[0] != TTY_NORMAL;
-       int copied = 0;
+       size_t copied = 0;
 
        do {
-               int goal = min_t(size_t, size - copied, TTY_BUFFER_PAGE);
-               int space = __tty_buffer_request_room(port, goal, need_flags);
+               size_t goal = min_t(size_t, size - copied, TTY_BUFFER_PAGE);
+               size_t space = __tty_buffer_request_room(port, goal, need_flags);
                struct tty_buffer *tb = port->buf.tail;
 
                if (unlikely(space == 0))

diff --git a/include/linux/tty_flip.h b/include/linux/tty_flip.h
index 8b781f7096057c0ca77a27f6df14181e3c8c00d3..569747364ae5fbd13122c66fcaa96f94d0d2ef68 100644 (file)
--- a/include/linux/tty_flip.h
+++ b/include/linux/tty_flip.h
@@ -10,9 +10,9 @@ struct tty_ldisc;
 int tty_buffer_set_limit(struct tty_port *port, int limit);
 unsigned int tty_buffer_space_avail(struct tty_port *port);
 int tty_buffer_request_room(struct tty_port *port, size_t size);
-int __tty_insert_flip_string_flags(struct tty_port *port, const u8 *chars,
-                                  const u8 *flags, bool mutable_flags,
-                                  size_t size);
+size_t __tty_insert_flip_string_flags(struct tty_port *port, const u8 *chars,
+                                     const u8 *flags, bool mutable_flags,
+                                     size_t size);
 int tty_prepare_flip_string(struct tty_port *port, u8 **chars, size_t size);
 void tty_flip_buffer_push(struct tty_port *port);
 int __tty_insert_flip_char(struct tty_port *port, u8 ch, u8 flag);
@@ -29,9 +29,9 @@ int __tty_insert_flip_char(struct tty_port *port, u8 ch, u8 flag);
  *
  * Returns: the number added.
  */
-static inline int tty_insert_flip_string_fixed_flag(struct tty_port *port,
-                                                   const u8 *chars, u8 flag,
-                                                   size_t size)
+static inline size_t tty_insert_flip_string_fixed_flag(struct tty_port *port,
+                                                      const u8 *chars, u8 flag,
+                                                      size_t size)
 {
        return __tty_insert_flip_string_flags(port, chars, &flag, false, size);
 }
@@ -48,15 +48,15 @@ static inline int tty_insert_flip_string_fixed_flag(struct tty_port *port,
  *
  * Returns: the number added.
  */
-static inline int tty_insert_flip_string_flags(struct tty_port *port,
-                                              const u8 *chars, const u8 *flags,
-                                              size_t size)
+static inline size_t tty_insert_flip_string_flags(struct tty_port *port,
+                                                 const u8 *chars,
+                                                 const u8 *flags, size_t size)
 {
        return __tty_insert_flip_string_flags(port, chars, flags, true, size);
 }
 
 
-static inline int tty_insert_flip_char(struct tty_port *port, u8 ch, u8 flag)
+static inline size_t tty_insert_flip_char(struct tty_port *port, u8 ch, u8 flag)
 {
        struct tty_buffer *tb = port->buf.tail;
        int change;
@@ -71,8 +71,8 @@ static inline int tty_insert_flip_char(struct tty_port *port, u8 ch, u8 flag)
        return __tty_insert_flip_char(port, ch, flag);
 }
 
-static inline int tty_insert_flip_string(struct tty_port *port,
-               const u8 *chars, size_t size)
+static inline size_t tty_insert_flip_string(struct tty_port *port,
+                                           const u8 *chars, size_t size)
 {
        return tty_insert_flip_string_fixed_flag(port, chars, TTY_NORMAL, size);
 }