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SubjectPatch to add guarding parentheses to some macros in linux/input.h
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Hi all.

This is a patch to add guarding parentheses around some macro argument
uses. This is good practice to avoid pitfalls like this:

ioctl (fd, EVIOCGABS (have_mt ? ABS_MT_POSITION_X : ABS_X), &abs);

Which currently totally does not do what is expected.

The attached patch adds parentheses to ensure correct operator precedence.

Please consider this for inclusion into the Linux Kernel.

Thanks,
Simon
- --
Simon Budig kernel concepts GbR
simon.budig@kernelconcepts.de Sieghuetter Hauptweg 48
+49-271-771091-17 D-57072 Siegen

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commit c88a91cb31a158a5e993484d91a0634a2aab1a43
Author: Simon Budig <simon@budig.de>
Date: Wed Jun 1 23:04:42 2011 +0200

input: add guarding parentheses to macros

Put parentheses around macro argument uses. This avoids pitfalls
for the programmer, where the argument expansion does not give the
expected result.

Signed-off-by: Simon Budig <simon.budig@kernelconcepts.de>

diff --git a/include/linux/input.h b/include/linux/input.h
index 9e5393d..31dd2b8 100644
--- a/include/linux/input.h
+++ b/include/linux/input.h
@@ -109,19 +109,19 @@ struct input_keymap_entry {
#define EVIOCSKEYCODE _IOW('E', 0x04, unsigned int[2]) /* set keycode */
#define EVIOCSKEYCODE_V2 _IOW('E', 0x04, struct input_keymap_entry)

-#define EVIOCGNAME(len) _IOC(_IOC_READ, 'E', 0x06, len) /* get device name */
-#define EVIOCGPHYS(len) _IOC(_IOC_READ, 'E', 0x07, len) /* get physical location */
-#define EVIOCGUNIQ(len) _IOC(_IOC_READ, 'E', 0x08, len) /* get unique identifier */
-#define EVIOCGPROP(len) _IOC(_IOC_READ, 'E', 0x09, len) /* get device properties */
-
-#define EVIOCGKEY(len) _IOC(_IOC_READ, 'E', 0x18, len) /* get global key state */
-#define EVIOCGLED(len) _IOC(_IOC_READ, 'E', 0x19, len) /* get all LEDs */
-#define EVIOCGSND(len) _IOC(_IOC_READ, 'E', 0x1a, len) /* get all sounds status */
-#define EVIOCGSW(len) _IOC(_IOC_READ, 'E', 0x1b, len) /* get all switch states */
-
-#define EVIOCGBIT(ev,len) _IOC(_IOC_READ, 'E', 0x20 + ev, len) /* get event bits */
-#define EVIOCGABS(abs) _IOR('E', 0x40 + abs, struct input_absinfo) /* get abs value/limits */
-#define EVIOCSABS(abs) _IOW('E', 0xc0 + abs, struct input_absinfo) /* set abs value/limits */
+#define EVIOCGNAME(len) _IOC(_IOC_READ, 'E', 0x06, (len)) /* get device name */
+#define EVIOCGPHYS(len) _IOC(_IOC_READ, 'E', 0x07, (len)) /* get physical location */
+#define EVIOCGUNIQ(len) _IOC(_IOC_READ, 'E', 0x08, (len)) /* get unique identifier */
+#define EVIOCGPROP(len) _IOC(_IOC_READ, 'E', 0x09, (len)) /* get device properties */
+
+#define EVIOCGKEY(len) _IOC(_IOC_READ, 'E', 0x18, (len)) /* get global key state */
+#define EVIOCGLED(len) _IOC(_IOC_READ, 'E', 0x19, (len)) /* get all LEDs */
+#define EVIOCGSND(len) _IOC(_IOC_READ, 'E', 0x1a, (len)) /* get all sounds status */
+#define EVIOCGSW(len) _IOC(_IOC_READ, 'E', 0x1b, (len)) /* get all switch states */
+
+#define EVIOCGBIT(ev,len) _IOC(_IOC_READ, 'E', 0x20 + (ev), (len)) /* get event bits */
+#define EVIOCGABS(abs) _IOR('E', 0x40 + (abs), struct input_absinfo) /* get abs value/limits */
+#define EVIOCSABS(abs) _IOW('E', 0xc0 + (abs), struct input_absinfo) /* set abs value/limits */

#define EVIOCSFF _IOC(_IOC_WRITE, 'E', 0x80, sizeof(struct ff_effect)) /* send a force effect to a force feedback device */
#define EVIOCRMFF _IOW('E', 0x81, int) /* Erase a force effect */
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