This patch fixes the bug introduced in
8f11e1cd03
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'
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.
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.
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.
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.
