- Detect whether a division by zero is done, and fail if so.
- Detect whether an invalid number is provided:
* If _tcstol() fails with errno == ERANGE, we've got an overflow or
underflow.
* If the next character where _tcstol() is not a whitespace but is a
character compatible with the first character of an identifier, the
number is invalid.
- Add + to the list of existing unary operators (!,~,-), and parse them
where many of these are present. Indeed, expressions like: +3, -+-+3,
!!-+3 (or with other unary ops, etc.) are valid.
- Operators constituted of more than one characters, can contain
whitespace separating their constituting characters.
Thus, "a + = 3" is equivalent to "a += 3" (and the same for -=, *=,
/=, %=, &=, |= and ^=), and "a < < 3" is equivalent to "a << 3" (and
the same for >>, <<= and >>=).
- After evaluating everything, if unparsed data remains, fail and bail out.
- Return Windows' CMD-compatible errorlevels.
See https://ss64.com/nt/set.html for more details.
Fixes some cmd_winetests.
Commands APPEND/DPATH and FTYPE are also concerned by this; however
we do not implement them in our CMD.EXE yet.
These commands set the ERRORLEVEL differently, whether or not they are
run manually from the command-line/from a .BAT file, or from a .CMD file:
- From command-line/.BAT file, these commands set the ERRORLEVEL only if
an error occurs. So, if two commands are run consecutively and the first
one fails, the ERRORLEVEL will remain set even if the second command
succeeds.
- However, when being run from a .CMD file, these command will always
set the ERRORLEVEL. In the example case described above, the second
command that succeeds will reset the ERRORLEVEL to 0.
This behaviour is determined from the top-level batch/script file being
run. This means that, if a .BAT file is first started, then starts a
.CMD file, the commands will still behave the .BAT way; on the opposite,
if a .CMD file is first started, then starts a .BAT file, these commands
will still behave the .CMD way.
To implement this we introduce one global BATCH_TYPE enum variable that
is initialized to the corresponding batch/script file type when the
top-level script is loaded. It is reset to "none" when that script
terminates.
See https://ss64.com/nt/errorlevel.html for more details,
section "Old style .bat Batch files vs .cmd Batch scripts",
and https://groups.google.com/forum/#!msg/microsoft.public.win2000.cmdprompt.admin/XHeUq8oe2wk/LIEViGNmkK0J
(comment by Mark Zbikowski).
- Restore any truncated space in the name prefix, before displaying
any error message.
- When trimming the name prefix from "special" characters (spaces, comma
and semicolon), so that e.g. "set ,; ,;FOO" displays all the variables
starting by "FOO", save also a pointer to the original name prefix, that
we will use for variables lookup as well.
This is done, because the SET command allows setting an environment variable
whose name actually contains these characters (e.g. "set ,; ,;FOO=42"),
however, by trimming the characters, doing "set ,; ,;FOO" would not allow
seeing such variables.
With the fix, it is now possible to show them.
