St uses a very good hack where mouse wheel genereates ^Y and ^E,
that are the same keys that less and vi uses for backward and
fordward scrolling. Scroll, as many terminal emulators, use
shift+Prev/Next for scrolling, but it is also using ^E and ^Y
for scroling, characters that are reserved in the POSIX shell
in emacs mode for end of line and yanking, making scroll unsable
in st.
This patch adds a new hack, making shift+wheel returning the
same sequences than shift+Prev/Next, meaning that scroll or
any other similar program will not be able to differentiate
between them.
St used to use backspace as BS until the commit 230d0c8, but due
to general lack of knowledge of lusers, we moved to the most common
configuration in linux to avoid answering the same question 3 times
per month. With the most common configuration we have a backspace
that returns a DEL, and we have a Delete key that doesn't return a
DEL character neither a BS.
When dealing with devices connected using a serial line (or even
with Plan9) it is more common Backspace as BS and Delete as DEL. For
this reason, st is not always the best tool when you talk with a
serial device.
This patch adds new terminfo entries for Backspace as BS and Delete
as DEL. A patch for confg.h is also added, to make easier switch
between both configurations.
When a read operation returns 0 then it means that we arrived to the end of the
file, and new reads will return 0 unless you do some other operation such as
lseek(). This case happens with USB-232 adapters when they are unplugged.
Scroll is a program that stores all the lines of its child and be used in st as
a way of implementing scrollback.
This solution is much better than implementing the scrollback in st itself
because having a different program allows to use it in any other program
without doing modifications to those programs.
CTRL+SHIFT is an impossible combination in the terminal world
(0x20 | x & 0x1F), so it is perfect to be used for internals
shortcuts of terminals, and being a double combination
reduces the prossibility of having comflicts.
ttywrite was assuming that if it could not write then it could
read, but this is not necessarily true, there are some situations
where you cannot read or write. The correct behaviour is to detect
if you can read or/and write.
When a line has no any character linelen is 0, so last = &term.line[y][MIN(lastx, linelen-1)]
generated a pointer to the end of the previous line. The best thing we can do in this case
is to add a newline, because we don't have a glyph to print (and consult its state of
wrapping).
wcwidth() returns -1 for all the non visible characters, but it doesn't
necessarilly mean that they are incorrect. It only means that they are not
printable.
Not always is desirable to create a pseudo terminal, and some times
we want to open a terminal emulator over a tty line. With this new
patch is possible to do someting like:
$ st -l /dev/ttyS0 115200
Without this option was needed to launch another terminal emulator
over st (for example minicom, picocom, cu, ...).
strsep() is not a POSIX function, and it means that every system
needs different defines to expose it. If the prototype of strsep
is not exposed then an ugly int/pointer is done and it might mean
a crash. The best solution?, to remove the strsep and make a custom
loop. If C programmers cannot do this kind of loops without calling
a library function, then maybe we should move all the suckless
software to Java.
Some programs can only deal with XA_STRING, and it makes impossible st
be able of copying to them. This patch makes st answer also to XA_STRING,
althought it sends utf8 strings. It is not a problem because moderm
applications must support utf8.
St has enacs, which must be printed if a program requires to use
the alternate charset (graphic charset), that in st case was to
select charset graphic for G1, but it was not useful
at all because smacs and rmacs were always redefining the value
of G0.
SI (0x0F or ^O) means Shift In, and it selects G1 charset definition,
and SO (0x0E or ^N) means Shift Out, and it selects G0 charset
definition, but st was doing just the inverse.
St runs an interactive shell and not a login shell, and it means
that profile is not loaded. The default terminal configuration
in some system is not the correct for st, but since profile is
not loaded there is no way of getting a script configures the
correct values.
St doesn't update the utmp files, this is the job of another
suckless tool, utmp. Utmp also opens a login shell (it is the
logical behaviour when you create a new user record) it is a
good option execute utmp and then get a correct input in
utmp, wtmp and lastlog file, and execute the content of the
profile.
We already have a csihandle() function, where is located code about
CSI sequences, so it is logical do the same with ESC sequences.
This change helps to simplify tcontrol(), which has a complex flow
and should be rewritten.
DEL character is not thecnically talking a C0 control character,
although it has some common properties with them, so it is useful
for us consider it as C0. Before this patch DEL (\177), was not
ignored as it ought to be.
DEL key has to generate the sequence ^[P in application mode,
because such sequence means delete current character. It implies
that the character sent in keypad mode must be ^? (DEL character).
Man page was repeating -f option, the second time instead of -i,
and this option was lost in usage() message. This patch also indent
the output of usage().
VT102ID is the sequence that the terminal returns when it is inquired
to identify itself. This value should be configurable in the same
way that another st parameters.
ISCONTROL chechks if a value is between 0 and 0x1f or
between 0x80 and 0x9f. Char signess depends of architecture
and compiler, so in some environment the second case is
always false (and wrong), Techo() calls ISCONTROL with a
char variable, whose type cannot be changed because tpuc()
expects a pointer to char, so the solution is to insert a
cast in the call to ISCONTROL.
This capability indicates that underscore '_' overstrike current
letter under the cursor. It means that you can generate a
underline 'b' using 'b^H_', because it writes a 'b' then backward
one characther and then overstrike '_'. St has not such behaviour,
so it is an error to have this capability.
tclearregion() was clearing regions using spaces and the current
attributes of the terminal. It was correct with all the modes excepct
underline, because they didn't affect the space character, but in
the case of underline it was a problem. A easy way of seeing this
problem is writing this in the last line of the terminal:
tput smul ; echo first; tput rmul; echo second; echo third
Fist was underlined, and second and third were not underlined, but
the spaces at the right of second was underlined becuause in the
previous scrool underline mode was set.
Master proccess was not showing any error message when the child
died with an error, and it was very confusing for the user (for
example with incorrect -e command).
One blinking mode is good enough, and two is too much. The best aproach
is emulate the fast blinking with the slow blinking, that it is more
used.
It is removed the flag ATTR_FASTBLINK because it has not a different
meaning of ATTR_BLINK, so it is not needed.
Signed-off-by: Roberto E. Vargas Caballero <k0ga@shike2.com>
This macro was not correct in some cases, and it was used only in
one place, where we did'nt get any benefit in performance of in size,
so the macro is removed and ceilf is used instead of it. The only
function needed from math.h is ceilf, so this patch defines the
prototype of it instead of including math.h.
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.
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.
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.
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.
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.
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
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.
sbase did some interesting modifications to arg.h (basically it
was fixed an incorrect use of the _ namespace), and this commit
take this last version for st.
vt100 has support for two defined charset, G0 and G1. Each charset
can be defined, but in each moment is selected only one of both
charset. This is usually used selecting a national charset in G0
and graphic charset in G1, so you can switch between graphic
charset and text charset without losing the national charset
already defined.
st hasn't support for national charsets, because it is an utf8
based terminal emulator, but it has support for graphic
charset because it is heavily used, but it only supports G0,
without understanding G1 selection sequences, which causes some
programs in some moments can print some garbage in the screen.
This patch adds a fake support for multiple charset definitions,
where we only support graphic charset and us-ascii charset, but
we allow more of one charset definition.
This patch allow define G0 until G3 charsets, but only accepts
select G0 or G1, and it accepts some national charset definitions
but all of them are mapped to us-ascii.
Some programs don't check the value of km and use smm and rmm
capabilites, and they cause the terminal change to meta enabled
mode even in cases where is not desirable.
Allmost all people is using the terminal waiting that meta sends
escape, so rmm and smm are not needed. If someone needs meta
sets 8 bit he can use the correct terminfo definition in TERM.
Colors definition can be changed using a OSC sequence, so
we have to reload them if we want be sure all the colors
are the correct.
Could be desirable free the colors allocated due to rgb
colors and inverse colors (XftColorAllocValues in xdraws),
but it is impossible due we use the same structure for all
of them.
This patch uses the bit 24 in the color descriptor as an indicator
of RGB color, so we can take the values and generating the XftColour
directly in xdraws.
There were two problems with match denfinition.
1) There was a forward declaration in the form:
static inline bool match(uint, uint);
but later the function was defined as:
inline bool
match(uint mask, uint state) {
This causes that there were two different functions in the code, one local
and inline, and other inline but extern. All was working without problems
due to we were using -Os, and the compiler was using the extern definition
and it was no expanding the static declaration. If you removed the -Os flag,
then you got linker errors due it was no able to find the static definition
of the static declaration.
2) The mask checking was incorrect because we were doing the test:
(state & mask) != state
and this test only was saying that at least all the enabled bits of state
were enabled also in mask, but no all the possible bits in mask. This was
the origin of the bug reported by Xavier Cartron, where he said it was
possible activated some shortcuts with some of the modifiers defined in the
config.h file.
draw is the function which update the Xwindow with the information st has,
and it is designed in a way that it must be called once in the main loop
(run function), and calling it in other places it is a waste of time.
The way st knows if there is a selection activated is checking if sel.ob.x
is equal to -1. In some parts of the code the way of disabling the selection
was only setting it to -1, but after it you can't be sure if the selection
is clearing from the terminal representation, because it is necessary mark
all the lines affected by the selection as dirty. Already there is a functon
which perform this task, selclear.
The commit b78c5085f7 changed the st behaviour enabling BCE capability,
that means erase regions using background color. Problem comes when you
clear a region with a selection, because in this case the real mode of the
Glyph is not the value of term.line[y][x], due in drawregion we had enabled
the ATTR_REVERSE bit.
Signed-off-by: Christoph Lohmann <20h@r-36.net>
- Shift + End : Delete until end of line.
- Control + End : Delete until end of screen.
When the End key is pressed without any modifier is not generated the
correct sequence for it (going to the end of the screen), because the size
of the terminal is not known, so it is not possible write a sequence for
this purpouse.
---
config.def.h | 10 ++++++++--
st.info | 2 ++
2 files changed, 10 insertions(+), 2 deletions(-)
Del : Delete character under cursor.
Shift + Del : Delete the line under cursor.
Ctrl + Del: Delete the full screen.
---
config.def.h | 16 ++++++++++++----
st.info | 2 ++
2 files changed, 14 insertions(+), 4 deletions(-)
