Ivan Delalande [Thu, 26 Jun 2014 02:30:43 +0000 (04:30 +0200)]
Fixed wrong nanosecond factor 10E6.
Commit
5edeec1 introduced a wrong factor for nanosecond computation, the correct
value is 1E6. Time and timeout values are 10 times less than they should be and
this cause high CPU usage.
Reported by pyroh on IRC. Thanks!
Signed-off-by: Roberto E. Vargas Caballero <k0ga@shike2.com>
FRIGN [Mon, 23 Jun 2014 14:51:51 +0000 (16:51 +0200)]
Use monotonic clock to prevent timing issues
This patch replaces the gettimeofday()/timeval-system with
uses of clock_gettime() with a monolithic clock and timespec-structs.
gettimeofday() is not accurate and prone to jumps and POSIX.1-2008
marks it as obsolete. Read more here [0].
The patch should speak for itself and decreases the binary
size for me by almost 200K(!).
[0]: http://blog.habets.pp.se/2010/09/gettimeofday-should-never-be-used-to-measure-time
Signed-off-by: Roberto E. Vargas Caballero <k0ga@shike2.com>
Eric Pruitt [Wed, 18 Jun 2014 13:39:57 +0000 (08:39 -0500)]
Fix typo in config.def.h
Signed-off-by: Roberto E. Vargas Caballero <k0ga@shike2.com>
Troy Sankey [Wed, 18 Jun 2014 17:41:26 +0000 (10:41 -0700)]
update size hints on zoom
On font zooming (i.e. xzoom()), window size hints are not updated. This
patch does that.
Signed-off-by: Roberto E. Vargas Caballero <k0ga@shike2.com>
Silvan Jegen [Fri, 6 Jun 2014 20:09:22 +0000 (22:09 +0200)]
Refactor the innermost loop of the xdraws function
Signed-off-by: Silvan Jegen <s.jegen@gmail.com>
Signed-off-by: Christoph Lohmann <20h@r-36.net>
Hiltjo Posthuma [Mon, 9 Jun 2014 15:19:15 +0000 (17:19 +0200)]
FAQ: update typo and escape code for smkx
Signed-off-by: Roberto E. Vargas Caballero <k0ga@shike2.com>
Christoph Lohmann [Sat, 7 Jun 2014 11:49:04 +0000 (13:49 +0200)]
Style police.
Roberto E. Vargas Caballero [Sat, 7 Jun 2014 11:23:45 +0000 (13:23 +0200)]
Simplify tdeftrans
FRIGN [Fri, 6 Jun 2014 12:08:51 +0000 (14:08 +0200)]
Remove unnecessary typedef
This should also fix compiling-errors on OpenBSD,
as reported by Nils R. Thanks!
Signed-off-by: Roberto E. Vargas Caballero <k0ga@shike2.com>
Colona [Thu, 5 Jun 2014 04:32:01 +0000 (06:32 +0200)]
Refactor selsnap SNAP_WORD.
Refactor the SNAP_WORD part in selsnap, and fix a bug that caused the word
delimiters to be ignored if it was at the very beginning or end of a wrapped
line.
Signed-off-by: Roberto E. Vargas Caballero <k0ga@shike2.com>
Colona [Wed, 4 Jun 2014 04:47:55 +0000 (21:47 -0700)]
Fix rectangular selection.
selsort computes the wrong normalized coordinates when rectangular
selection is enabled, causing rectangular selection to only work
when going toward either the top left corner, or the bottom right
one.
Signed-off-by: Roberto E. Vargas Caballero <k0ga@shike2.com>
Hiltjo Posthuma [Tue, 3 Jun 2014 15:55:53 +0000 (17:55 +0200)]
tiny cleanup
Signed-off-by: Roberto E. Vargas Caballero <k0ga@shike2.com>
Colona [Tue, 3 Jun 2014 02:34:58 +0000 (04:34 +0200)]
Make selection consistent over line breaks.
Currently, selection is expanded to the end of the line over line breaks only in
regular selection mode, when the line in not empty and when going down and/or
right. This covers all the cases including word selection mode, with the
exception of rectangular selection because it would make this mode too rigid.
This adjustment is made in selsort so I renamed it to selnormalize to better
reflect what it does now.
Signed-off-by: Roberto E. Vargas Caballero <k0ga@shike2.com>
Christoph Lohmann [Sun, 1 Jun 2014 15:08:16 +0000 (17:08 +0200)]
Fixing color and refactor xsetcolorname.
By the recommendation of FRIGN I refactored xsetcolorname to remove the
unnecessary r, g, b variables when allocating a new color. Colors are
now freed and set to the new color. A die() should not happen here. Oth‐
erwise it is easy for applications to kill st. St should be resilent to
malicious input.
Second this patch standardises the naming of »color«. There is no
»colour« here. Maybe in some parts of the world.
Christoph Lohmann [Sun, 1 Jun 2014 14:52:19 +0000 (16:52 +0200)]
Revert "Refactor xsetcolorname()"
This reverts commit
a32c5f5726f514b49bd396f27aab0e78c40126d3.
FRIGN [Sun, 25 May 2014 10:13:22 +0000 (12:13 +0200)]
Refactor xsetcolorname()
I mainly improved the slightly off algorithm used to load colours in the 256-colour-space and
removed unnecessary local values (r,g,b,colour).
"colour" is not necessary as a punchbag for XftColorAlloc[Value,Name], as they don't mess with
the result-adress until they are absolutely sure everything worked out[0].
Being at it, I changed the error-returns for AllocValue to dies (just like in xloadcols()), as
a failure is most likely an OOM-situation you better catch early.
In case of an invalid name everything stays the same.
[0]: http://www.opensource.apple.com/source/X11libs/X11libs-40/libXft/libXft-2.1.13/src/xftcolor.c
Signed-off-by: Christoph Lohmann <20h@r-36.net>
Balazs Kezes [Sat, 31 May 2014 21:24:58 +0000 (22:24 +0100)]
Don't report release events for mouse wheel
Signed-off-by: Christoph Lohmann <20h@r-36.net>
Christoph Lohmann [Sun, 1 Jun 2014 13:54:28 +0000 (15:54 +0200)]
Fixing italic bold.
Thanks Felipe Spychalski <spychalski@gmail.com> for the patch!
Alexander [Mon, 26 May 2014 05:23:56 +0000 (09:23 +0400)]
Fixed copying empty lines inside selection.
The code was assuming that empty lines have implicit wrap-around attribute.
Signed-off-by: Roberto E. Vargas Caballero <k0ga@shike2.com>
Christoph Lohmann [Sat, 24 May 2014 19:27:54 +0000 (21:27 +0200)]
Fix some more LICENSE changes.
FRIGN [Sat, 24 May 2014 19:07:53 +0000 (21:07 +0200)]
Add FRIGN to License, remove trailing whitespace
Signed-off-by: Christoph Lohmann <20h@r-36.net>
Christoph Lohmann [Sat, 24 May 2014 11:52:24 +0000 (13:52 +0200)]
Brightening is again on the TODO list.
Christoph Lohmann [Sat, 24 May 2014 11:48:44 +0000 (13:48 +0200)]
Fixing trailing whitespaces.
FRIGN [Thu, 22 May 2014 13:00:33 +0000 (15:00 +0200)]
Fix colour-model and simplify xloadcols()
Signed-off-by: Christoph Lohmann <20h@r-36.net>
Hiltjo Posthuma [Mon, 12 May 2014 12:39:37 +0000 (14:39 +0200)]
Allow mouse selection override using ShiftMask
Similar to xterm or urxvt holding shift before selecting text with the mouse
allows to override copying text. For example in tmux with "mode-mouse on" or
vim (compiled with --with-x), mc, htop, etc.
forceselmod in config.h sets the modifier to use this mode, by default
ShiftMask.
Signed-off-by: Hiltjo Posthuma <hiltjo@codemadness.org>
Christoph Lohmann [Fri, 9 May 2014 15:12:58 +0000 (17:12 +0200)]
Redraw needs all dirty lines to have flash etc. work.
Colona [Fri, 9 May 2014 08:23:53 +0000 (10:23 +0200)]
End a sequence only on CAN, SUB, \a and C1s.
Colona [Wed, 7 May 2014 08:05:27 +0000 (10:05 +0200)]
Also clears ESC_START on interrupt characters during sequences.
Otherwise, the rest of the input is interpreted as a new escape
sequence.
For the ESC character, ESC_START is re-set in tcontrolcode.
noname [Fri, 25 Apr 2014 14:26:54 +0000 (18:26 +0400)]
Consistent FALLTHROUGH comments.
Roberto E. Vargas Caballero [Tue, 29 Apr 2014 07:58:55 +0000 (09:58 +0200)]
Fix displaying control code
Control code are never displayed. It is not important if graphic
charset is displayed or not.
Roberto E. Vargas Caballero [Tue, 29 Apr 2014 06:58:10 +0000 (08:58 +0200)]
Remove ATTR_GFX and tselcs
ATTR_GFX was used long time ago to detect when terminal was in
graphic mode. Today graphic mode is implemented using a charset
pointer, so ATTR_GFX is not needed anymore because graphic
condition can be detected directly checking if current charset
is GRAPHICS C0.
noname [Mon, 28 Apr 2014 22:35:22 +0000 (02:35 +0400)]
Do not save cursor in tresize.
This patch fixes the bug introduced in
8f11e1cd034ff28ca47bb4955505db7fa8016ba8
To reproduce the bug:
1. Save cursor: printf '\e[s'
2. Load cursor: printf '\e[u'
3. Resize st window.
4. Load cursor again: printf '\e[u'
noname [Sun, 27 Apr 2014 11:16:41 +0000 (15:16 +0400)]
Simplify selected().
noname [Sun, 27 Apr 2014 11:39:53 +0000 (15:39 +0400)]
Do not export chscale and cwscale.
noname [Sun, 27 Apr 2014 22:41:17 +0000 (02:41 +0400)]
Simplify xunloadfonts.
noname [Sun, 27 Apr 2014 11:40:23 +0000 (15:40 +0400)]
Remove one indentation level in getsel().
noname [Sun, 27 Apr 2014 11:40:01 +0000 (15:40 +0400)]
Remove unused dump() function.
noname [Sun, 27 Apr 2014 11:39:47 +0000 (15:39 +0400)]
Add missing function prototypes.
noname [Sun, 27 Apr 2014 11:39:39 +0000 (15:39 +0400)]
Use MODBIT in xseturgency.
noname [Sun, 27 Apr 2014 11:39:29 +0000 (15:39 +0400)]
Compute ena_sel as one expression.
Roberto E. Vargas Caballero [Sun, 27 Apr 2014 08:25:15 +0000 (10:25 +0200)]
Simplify expressions in tputc()
Roberto E. Vargas Caballero [Sat, 26 Apr 2014 07:30:53 +0000 (09:30 +0200)]
Fix misplaced break
This misplaced break was causing an incorrect fall through
from DSR to DECSTBM.
Roberto E. Vargas Caballero [Sat, 26 Apr 2014 07:24:04 +0000 (09:24 +0200)]
Create a function for DEC test
Almost of the sequences execute their action in a separate function,
which is good because helps to read the full set of sequences
faster.
Roberto E. Vargas Caballero [Mon, 28 Apr 2014 16:32:09 +0000 (18:32 +0200)]
Fix tputc control code handling
The patch
53105cf modified how control codes were detected, because
it tried to handle also C1 control codes (0x80-0x9f), that have
upper bit to 1, so they are multi byte character in utf8.
Code was checking the value of width in order to known that after
decoding the unicode point had a width of 1 byte, but it as incorrect
because this width is the columnb width.
Roberto E. Vargas Caballero [Fri, 25 Apr 2014 23:45:10 +0000 (01:45 +0200)]
Remove repeated initialisation of term.esc
Once a sequence is completed term.esc must return to 0, so
instead of repeating this expression in all the cases is
better put it at the end of the block.
Roberto E. Vargas Caballero [Fri, 25 Apr 2014 23:34:46 +0000 (01:34 +0200)]
Cancel DCS with SUB, CAN, ESC or any CC1 code
From http://www.vt100.net/docs/vt510-rm/chapter4:
*The VT510 ignores all following characters until it receives a
SUB, ST, or any other C1 control character.
So OSC, PM and APC sequence ends with a SUB (it cancels the sequence
and show a question mark as error), ST or any another C1 (8 bits)
code, or their C0 (7 bits) equivalent sequences (at this moment we
do not handle C1 codes, but we should). But it is also said that:
Cancel CAN
1/8 Immediately cancels an escape sequence, control sequence,
or device control string in progress. In this case, the
VT510 does not display any error character.
Escape ESC
1/11 Introduces an escape sequence. ESC also cancels any escape
sequence, control sequence, or device control string in
progress.
Markus Teich [Sat, 26 Apr 2014 21:50:37 +0000 (23:50 +0200)]
add break;s for last cases in switch statements
noname [Fri, 25 Apr 2014 22:12:41 +0000 (00:12 +0200)]
Do not eat ESC character if control string is not properly terminated.
Currently tputc handles the case of too long control string waiting for
the end of control string.
Another case is when there is ESC character is encountered but is not
followed by '\\'. In this case st stops processing control string,
but ESC character is ignored.
After this patch st processes ESC characters in control strings properly.
Test case:
printf '\e]0;abc\e[1mBOLD\e[0m'
Also ^[\ is actually processed in the code that handles ST.
According to ECMA-048 ST stands for STRING TERMINATOR and is used to
close control strings.
noname [Fri, 25 Apr 2014 14:28:00 +0000 (18:28 +0400)]
Fix for multibyte characters in techo.
Works for both signed and unsigned char.
noname [Fri, 25 Apr 2014 14:27:48 +0000 (18:27 +0400)]
s/DSC/DCS/ DCS stands for DEVICE CONTROL STRING
noname [Fri, 25 Apr 2014 14:27:26 +0000 (18:27 +0400)]
Use xwrite instead of write.
noname [Fri, 25 Apr 2014 14:27:15 +0000 (18:27 +0400)]
Remove unnecessary break
noname [Fri, 25 Apr 2014 14:26:43 +0000 (18:26 +0400)]
Comment fix.
Colona [Thu, 24 Apr 2014 18:35:41 +0000 (20:35 +0200)]
On terminal resize, clear the alt screen with its own cursor.
Currently the alternate screen get messed up on resize if it has
different colors or mode.
noname [Wed, 23 Apr 2014 19:12:45 +0000 (23:12 +0400)]
Optimize tputtab.
Before this patch executing
printf '\e[10000000000I'
or
printf '\e[10000000000Z'
resulted in long delay.
noname [Wed, 23 Apr 2014 19:12:36 +0000 (23:12 +0400)]
Use != instead of ^ for logical values.
sel.alt is only changed by
sel.alt = IS_SET(MODE_ALTSCREEN);
noname [Wed, 23 Apr 2014 19:12:29 +0000 (23:12 +0400)]
Use BETWEEN macro in xsetcolorname and fix style.
Christoph Lohmann [Fri, 25 Apr 2014 20:34:24 +0000 (22:34 +0200)]
Conformity in the -g geometry handling.
Thanks to Yuri Karaban for suggesting this!
These changes make -g correspond to <cols>x<rows> and honor it so non-tiling
window managers can work with the size hints afterwards. It also adds a -i
flag to force the window size. This is needed so -g keeps being useful in dwm.
Roberto E. Vargas Caballero [Fri, 25 Apr 2014 15:24:12 +0000 (17:24 +0200)]
Simplify a bit more tdeletechar and tinsertblank
The large and repeated expression used in memmove to indirect
the line can be simplified using a pointer, that makes more
clear where begins and where ends the movement.
noname [Tue, 22 Apr 2014 22:08:13 +0000 (02:08 +0400)]
Simplify tdeletechar and tinsertblank and fix memory corruption.
Current CSI parsing code uses strtol to parse arguments and allows them
to be negative. Negative argument is not properly handled in tdeletechar
and tinsertblank and results in memory corruption in memmove.
Reproduce with printf '\e[-500@'
Patch also removes special handling for corner case and simplifies
the code.
Removed
term.dirty[term.c.y] = 1
because tclearregion sets dirty flag.
noname [Sun, 20 Apr 2014 13:26:39 +0000 (17:26 +0400)]
Style fixes in tscrollup.
noname [Sun, 20 Apr 2014 13:26:50 +0000 (17:26 +0400)]
Do not set dirty flag twice in tscrollup and tscrolldown.
noname [Sun, 20 Apr 2014 13:26:13 +0000 (17:26 +0400)]
Use tsetdirt in tscrollup and tscrolldown.
tscrollup and tscrolldown do not use tsetdirt, but their code is
equivalent to
tsetdirt(orig, term.bot-n);
tsetdirt(orig+n, term.bot);
tclearregion also marks cleared lines as dirty.
In tscrolldown it sets lines from term.bot-n+1 to term.bot dirty, and in
tscrollup it sets lines from orig to orig+n-1 dirty.
In both functions all lines from orig to term.bot are effectively set
dirty, but in tscrolldown lines from orig+n to term.bot are set dirty
twice, and in tscrollup lines from orig to term.bot-n are set dirty
twice.
These patches make it clear which lines are set dirty and sets them
dirty once in each funciton.
noname [Tue, 22 Apr 2014 20:26:07 +0000 (00:26 +0400)]
Fix techo handling of control and multibyte characters.
techo compares signed char to '\x20'. Any character with code less then
'\x20' is treated as control character. This way characters with MSB
set to 1 are considered control characters too.
Also this patch makes techo display DEL character as ^?.
To reprocuce the bug, enable echo mode using printf '\e[12l',
then type DEL character or any non-ASCII character.
noname [Tue, 22 Apr 2014 17:59:48 +0000 (21:59 +0400)]
Make xrealloc and xstrdup style consistent.
noname [Tue, 22 Apr 2014 17:59:39 +0000 (21:59 +0400)]
Use BETWEEN in tsetchar.
noname [Tue, 22 Apr 2014 17:59:32 +0000 (21:59 +0400)]
Use uint and uchar instead of unsigned int and unsigned char.
noname [Tue, 22 Apr 2014 17:59:21 +0000 (21:59 +0400)]
Remove argument names from function prototypes.
noname [Tue, 22 Apr 2014 17:59:14 +0000 (21:59 +0400)]
Style fix in tdumpsel.
noname [Tue, 22 Apr 2014 17:59:01 +0000 (21:59 +0400)]
Use BETWEEN in tinsertblankline and tdeleteline.
Christoph Lohmann [Tue, 22 Apr 2014 17:22:58 +0000 (19:22 +0200)]
It's 2014 now.
noname@inventati.org [Sun, 20 Apr 2014 09:08:09 +0000 (13:08 +0400)]
move MODBIT to Macros section
Patch moves MODBIT to macros section and uses it in tselcs.
noname@inventati.org [Sun, 20 Apr 2014 11:41:40 +0000 (15:41 +0400)]
misplaced parenthesis in LEN macro
Markus Teich [Sun, 20 Apr 2014 11:15:40 +0000 (13:15 +0200)]
remove confusing SERRNO macro
I found the SERRNO Macro slightly confusing, since you have to look
it up, if you don't know it already. A web search showed it does
not seem to be any kind of standard. Also there was no reason in
the commit log when it was introduced in 2009. As you can see it
also leads to new patches, which don't use this macro (probably the
author did not know about it).
noname@inventati.org [Sun, 13 Apr 2014 16:21:32 +0000 (20:21 +0400)]
Simplify techo
Remove special case for \e because it is handled well by "control code"
case.
noname@inventati.org [Sat, 5 Apr 2014 16:54:01 +0000 (20:54 +0400)]
typedefs instead of #defines
Replaced #defines with typedefs where possible, patch attached.
q@c9x.me [Wed, 9 Apr 2014 18:37:23 +0000 (20:37 +0200)]
fix cursor handling when alt screen is disabled
I don't like this alt screen thing, but when
allowaltscreen == 0, the cursor is still saved
and restored after calling 'less' (or 'man').
This patch makes allowaltscreen == 0 usable.
Roberto E. Vargas Caballero [Tue, 15 Apr 2014 06:11:47 +0000 (08:11 +0200)]
Merge remote-tracking branch 'origin/master' into omaster
Christoph Lohmann [Fri, 11 Apr 2014 16:11:25 +0000 (18:11 +0200)]
Removing two unnecessary gettimeofday().
Toaster Toaster [Mon, 7 Apr 2014 17:53:59 +0000 (10:53 -0700)]
Increment XSync consistency
This patch cleans up a style inconsistency.
Roberto E. Vargas Caballero [Fri, 11 Apr 2014 13:08:37 +0000 (15:08 +0200)]
Fix Backspace and Delete characters
Backspace key must generate the backspace character (\010) and
Delete key must generate the delete character (\0177). In
some systems the kernel configuration for erasing previous character
is \0177, so some programs (for example cat, ed, mail, ...), can not
understand the correct meaning of backspace. In this cases it is only
needed this command:
stty erase \b
Christoph Lohmann [Sat, 5 Apr 2014 18:40:11 +0000 (20:40 +0200)]
0.5 release.
Christoph Lohmann [Sat, 5 Apr 2014 18:39:46 +0000 (20:39 +0200)]
Updating the TODO in preparating for 0.5.
Christoph Lohmann [Sat, 5 Apr 2014 18:34:57 +0000 (20:34 +0200)]
There is no need for a full dirt redraw.
Christoph Lohmann [Wed, 2 Apr 2014 07:26:28 +0000 (09:26 +0200)]
Fixing a compiler warning with the assignment.
Rafa Garcia Gallego [Wed, 26 Mar 2014 22:58:27 +0000 (23:58 +0100)]
Fix segfault when pressing PrintScr without a selection
Damian Okrasa [Tue, 25 Mar 2014 19:20:26 +0000 (20:20 +0100)]
new utf decoder
This patch replaces current utf decoder with a new one, which is ~50
lines shorter and should be easier to understand. Parsing 5 and 6
sequences, if necessary, requires trivial modification of UTF_SIZ
constant and utfbyte, utfmask, utfmin, utfmax arrays.
Roberto E. Vargas Caballero [Mon, 10 Mar 2014 14:16:26 +0000 (15:16 +0100)]
Merge branch 'master' of ssh://suckless.org/gitrepos/st
Roberto E. Vargas Caballero [Sat, 1 Feb 2014 10:11:11 +0000 (11:11 +0100)]
Add terminfo entries for printer
These capabilities inform to programs how print in local printer
of the terminal.
Roberto E. Vargas Caballero [Sat, 1 Feb 2014 12:41:58 +0000 (13:41 +0100)]
Add sequence for printing the current selection
This is very usefull in order to can select what is sent
to the plumber.
Roberto E. Vargas Caballero [Fri, 31 Jan 2014 22:05:42 +0000 (23:05 +0100)]
Add key definition for printer sequences
These new combinations generate the same behaviour (basically) of
vt102. It is a good way of communicating st with other programs.
[0] http://www.vt100.net/docs/vt102-ug/chapter2.html
Roberto E. Vargas Caballero [Fri, 31 Jan 2014 21:25:51 +0000 (22:25 +0100)]
Add MC for the full screen
This sequence is very useful because allows comunicate the content
of the terminal to another program.
Roberto E. Vargas Caballero [Fri, 31 Jan 2014 20:53:53 +0000 (21:53 +0100)]
Add MC for a single line
This sequence print the current line. It is different to the
'printer on' sequence, where all the characters that arrive to the
terminal are printer. Here only the ascii characters are printed.
Christoph Lohmann [Sat, 1 Mar 2014 10:04:03 +0000 (11:04 +0100)]
Style cleanup.
Add some note about the main reason why st is still that big.
Christoph Lohmann [Sat, 1 Mar 2014 08:22:57 +0000 (09:22 +0100)]
Style matters.
Roberto E. Vargas Caballero [Fri, 31 Jan 2014 19:57:09 +0000 (20:57 +0100)]
Add MC sequence
This sequence control when the printer is enabled or disabled. This
sequence control the behaviour of the -o option.
Roberto E. Vargas Caballero [Sat, 1 Feb 2014 10:12:47 +0000 (11:12 +0100)]
Add xstrdup function
Since we are using xmalloc, xrealloc ..., then it is not logical
call directly to strdup.
Signed-off-by: Roberto E. Vargas Caballero <k0ga@shike2.com>
Roberto E. Vargas Caballero [Tue, 4 Feb 2014 10:46:45 +0000 (11:46 +0100)]
Merge remote-tracking branch 'origin/master'
Christoph Lohmann [Mon, 3 Feb 2014 19:54:25 +0000 (20:54 +0100)]
Removing the w3img support.
The patch to add w3img support destroys our way to handle fps and so stop
wasting resources on fast scrolling. Due to w3img being a hack to display
images in an ugly way, is there no need to support this. Use some real way to
display images.
Roberto E. Vargas Caballero [Fri, 31 Jan 2014 16:30:00 +0000 (17:30 +0100)]
Remove non defined behaviour in selcopy
It is not defined when lateral effects of expressions are
calculated, so an expression as:
--last >= gp && !(selected(last - gp, y)
is non portable.