[PATCH 2/2] vt: make mouse selection of non-ASCII consistent

From: Adam Borowski
Date: Mon Mar 27 2017 - 06:38:07 EST


For some reason a handful of ISO-8859-1 symbols are excluded from "word
chars" while the vast majority of Unicode is hard-coded as included, even
when inappropriate (we really would want to _not_ select line-drawing/etc).
Those symbols are: ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÃÃ

Thus, let's not special-case any non-ASCII anymore. Attempts to set these
via ioctl will be silently ignored.

As an extra bonus, we debloat the kernel by 128 bytes.

Signed-off-by: Adam Borowski <kilobyte@xxxxxxxxxx>
---
drivers/tty/vt/selection.c | 16 ++++++----------
1 file changed, 6 insertions(+), 10 deletions(-)

diff --git a/drivers/tty/vt/selection.c b/drivers/tty/vt/selection.c
index 2252e11d8347..c81c99165ea6 100644
--- a/drivers/tty/vt/selection.c
+++ b/drivers/tty/vt/selection.c
@@ -80,21 +80,17 @@ void clear_selection(void)

/*
* User settable table: what characters are to be considered alphabetic?
- * 256 bits. Locked by the console lock.
+ * 128 bits. Locked by the console lock.
*/
-static u32 inwordLut[8]={
+static u32 inwordLut[4]={
0x00000000, /* control chars */
0x03FFE000, /* digits and "-./" */
0x87FFFFFE, /* uppercase and '_' */
0x07FFFFFE, /* lowercase */
- 0x00000000,
- 0x00000000,
- 0xFF7FFFFF, /* latin-1 accented letters, not multiplication sign */
- 0xFF7FFFFF /* latin-1 accented letters, not division sign */
};

static inline int inword(const u16 c) {
- return c > 0xff || (( inwordLut[c>>5] >> (c & 0x1F) ) & 1);
+ return c > 0x7f || (( inwordLut[c>>5] >> (c & 0x1F) ) & 1);
}

/**
@@ -106,10 +102,10 @@ static inline int inword(const u16 c) {
*/
int sel_loadlut(char __user *p)
{
- u32 tmplut[8];
- if (copy_from_user(tmplut, (u32 __user *)(p+4), 32))
+ u32 tmplut[4];
+ if (copy_from_user(tmplut, (u32 __user *)(p+4), 16))
return -EFAULT;
- memcpy(inwordLut, tmplut, 32);
+ memcpy(inwordLut, tmplut, 16);
return 0;
}

--
2.11.0