some minor style changes.

XK_NO_MOD match a key without modifiers and XK_ANY_MOD match a key does not
matter what modifiers are pressed to. Like they are mask the best value for
XK_ANY_MOD is all the bits to 1, so the and with any state will be equal to
the state. This also imply that is necessary check the case for XK_NO_MOD
(no modifiers at all) with some modifier in state, and the inverse
(some mask different to XK_ANY_MOD or XK_NO_MOD and no modifiers in state).
---
 st.c |   12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

When Shift + Tab is pressed X server send the event XK_ISO_Left_Tab with
ShiftMask, so this is the entry we need in config.def.h

This patch also revert the previous patch for this issue because it breaks
the keyboard.
---
 config.def.h |    2 +-
 st.c         |    2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

Some keys were in the Key array while others were hardcoded in
kpress().This cause some problems with some keys which can generate more of
one string based in the configuration of the terminal.
---
 config.def.h |   70 ++++++++++++++++++++++++++++++++++++++++-----------------
 st.c         |   71 +++++++++++++++++++++++++---------------------------------
 2 files changed, 79 insertions(+), 62 deletions(-)

Shift + Insert is used like a hot key for paste the selection, so it is more
logical move it to shortcut array instead of having special code for it.
---
 config.def.h |    1 +
 st.c         |   13 +++----------
 2 files changed, 4 insertions(+), 10 deletions(-)

Keypad mode is used for detecting when keys in the auxiliary keypad are
pressed, while cursor mode is used for detecting when a cursor is pressed,
but they are different modes.

St was mixing both modes and DECPAM and DECPNM modified the cursor mode, and
this was incorrect.
---
 st.c    |    5 +++--
 st.info |    4 ++--
 2 files changed, 5 insertions(+), 4 deletions(-)

This sequence enable/disable the local echo.
---
 st.c |   76 ++++++++++++++++++++++++++++++++++++++++++++++++------------------
 1 file changed, 56 insertions(+), 20 deletions(-)

These sequences will be never implemented and in this moment they are
generating a lot of noise.
---
 st.c |   14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

DECARM modify the auto repeat settings in the keyboard, and since we can not
modify this setting in the Xserver the best solution is only ignore it.
---
 st.c |    3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

VPR stands for Move cursor down a number of rows, and the code was moving
the cursor up instead of moving it down.
---
 st.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

DECOM sequence allows to the user defines a new home position. The home
position is used as base for all the movement commands except HVP and
VPA. It is important notice than DECSLM moves cursor to absolute position
0,0.
---
 st.c |   33 ++++++++++++++++++++++++++-------
 1 file changed, 26 insertions(+), 7 deletions(-)

After terminal reset saved terminal position is reset to 0, allowing know
where cursor will go in next restore cursor operation.
---
 st.c |    2 ++
 1 file changed, 2 insertions(+)

Since relational expresions are always evaluated to 0 or 1, we can use
bitwise xor operator instead of using more complex boolean expressions.
---
 st.c |   14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

Sequences like DECSC, DECRC, ESC [?1047l or ESC [?1047h save and restore
cursor attributes, than taken from vt100 manual are:

       Save Cursor (DECSC) ESC   7
       ===========================
       Saves the following in terminal memory.

      - cursor position
      - graphic rendition
      - character set shift state
      - state of wrap flag
      - state of origin mode

      Restore Cursor (DECRC) ESC 8
      ===========================
      Restores the states described for (DECSC) above. If none of these
      characteristics were saved, the cursor moves to home position; origin
      mode is reset; no character attributes are assigned; and the default
      character set mapping is established.

This implies that hide attribute of the cursor should not be saved/restored
in these sequences. The best way to fix this problem is moving hide
attribute into the terminal mode, instead of having it in the cursor state.
---
 st.c |   12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

Thanks c00kiemon5ter!

useful, but easy to implement.

possible. Thanks!

variables. Thanks! xinit() and ttynew() had to be switched in their
call-appearance. Otherwise xw.win is not set.

not emulate the vt100 behaviour of selecting all whitespaces. Thanks!

write can write less bytes than we request, so it is necessary check the
return value, in case of error print a message and don't continnue writing
in the file.
---
 st.c |   39 ++++++++++++++++++++++++++++++---------
 1 file changed, 30 insertions(+), 9 deletions(-)

should really learn opthalmology instead. :O

This sequence was used by DEC personal in to for verifying the screen adjust
of terminals. It is the unique test sequence implemented by all the
emulators, and I think it is because they want be conforms with vttest which
uses this sequence in some tests.
---
 st.c |   31 +++++++++++++++++++++++--------
 1 file changed, 23 insertions(+), 8 deletions(-)

If vt100_0 is a automatic variable then it is initializated in each call to
tsetchar, but if the variable is static it is initializated only in compile
time.
---
 st.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Do not send NUL character in the identification (use (sizeof(VT102ID) - 1),
and finish  the sequence once you execute it.
---
 st.c |    5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

These sequences are used by the host in order to can detect which kind of
terminal is connected. St will answer like a vt102 terminal with this patch.
---
 st.c |    9 +++++++++
 1 file changed, 9 insertions(+)

Non handled codes must be ignored, except in graphic mode. Also STR
sequences have higher priority than control codes, so they must be handled
before of them.
---
 st.c |  160 ++++++++++++++++++++++++++++++++++++------------------------------
 1 file changed, 87 insertions(+), 73 deletions(-)

SI and SO allows change the G0 and G1 selection. This implementation is not
full vt100 compatible, but it is complatible with linux virtual terminal
implementation. For full vt100 compatibility we need remake a lot of stuff
relate to the different charmaps.
---
 st.c |    7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

These control codes reset any escape sequence already initialised.
---
 st.c |    7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

Add the documentation from the vt100 manual programmer:

Control 	Octal      Action Taken
Character	Code
-------------------------------------------
NUL		000	Ignored on input (not stored in input buffer;
			see full duplex protocol).
ENQ		005	Transmit answerback message.
BEL		007	Sound bell tone from keyboard.
BS		010	Move the cursor to the left one character position,
			unless it is at the left margin,
			in which case no action occurs.
HT		011	Move the cursor to the next tab stop,
			or to the right margin if no further tab stops
			are present on the line.
LF		012	This code causes a line feed or
			a new line operation. (See new line mode).
VT		013	Interpreted as LF.
FF		014	Interpreted as LF.
CR		015	Move cursor to the left margin on the current line.
SO		016	Invoke G1 character set, as designated by SCS
			control sequence.
SI		017	Select G0 character set, as selected by ESC ( sequence.
XON		021	Causes terminal to resume transmission.
XOFF		023	Causes terminal to stop transmitted all codes
			except XOFF and XON.
CAN		030	If sent during a control sequence, the sequence is
			immediately terminated and not executed. It also causes
			the error character to be displayed.
SUB		032	Interpreted as CAN.
ESC		033	Invokes a control sequence.
DEL		177	Ignored on input (not stored in input buffer).
--------------------------------------------
---
 st.c |   28 +++++++++++++++++++---------
 1 file changed, 19 insertions(+), 9 deletions(-)

if something needs to be drawn close to it.