So this started with addressing CID 174264: Big parameter passed by value (PASS_BY_VALUE), but then I fell down the constification rabbit hole. :-)

This will allow naming consistency in encode/*
This is the fix you're looking for Keyop. :)

This won't impact Synchronet as it has a separate signal handling
thread, but we still need to behave properly for processes that
don't.  I'm also saying that ENOMEM does not indicate a disconnection,
though it may be better to pretend it was disconnected...

There were 2 bug identified by issue #230:
- the "Fwd:" prefix being added to the message subject was being treated as a filename. I first thought to just remove this subject tag, but then thought it best to just ignore obviously invalid filenames in the subject in the first place.

- when forwarding files to a netmail address, the 'to' extension (user number) is 0, so the file will be in the data/file/####.out directory of the sender instead.

We have 4 places (at least) where the message subjects are parsed and only one of those places currently supports quoted filenames (e.g. with spaces in them) and some of the others (e.g. QWK) don't support multiple filenames at all. That should be fixed.

Reverted the SAFECOPY() NULL source-pointer magic "(null)" string thing as that caused a different Coverity issue. Explicitly check for NULL at the call-sites instead.

Reverted the SAFECOPY() NULL source-pointer magic "(null)" string thing as that caused a different Coverity issue. Explicitly check for NULL at the call-sites instead.

Hopefully not introducing any bugs in the process.

Hopefully not introducing any bugs in the process.

Don't display at all if smb_getplaintext() returns a blank string.
Don't display "(null)" if there's no text sub-type.

Since we're calling smb_getplaintext() manually here, and its not going to return the comment headers as part of the plain-text (the way smb_getmsgtxt() can), so we need to display find/display the comment headers first.

Copy some code from atcodes.cpp to show all the aux and network attributes.

Also, the MsgAttr text.dat string only contains 17 %s's but we were passing 18, so the last attribute (KillSent) would never be shown.

Instead, split this into 3 strings and just pass those 3 strings to the MsgAttr format string along with a ton of blank strings. So we don't have to keep updating the MsgAttr text.dat string every time we add more attribute flags (that was kind of ridiculous).

The return value of getlastmsg() is displayed as the total messages in a
sub-board when scanning subs. For sub-boards that allow voting, use the new
smb_msg_count() function to determine the number of displayable messages.

- hot spots are clickable screen areas (e.g. in menus and prompts) that   generate key-strokes
- commands may be from 1 to 127 ASCII-characters in length
- currently using the X10 mouse reporting mode, may change
- all mnemonics strings (~Example) are automatically hot-spots
- The new ~ @-code defines a hot spot
- Any screen-clear operation clears all hot spots
- sbbs now tracks the current screen (cursor position) row
- eliminated the old "tos" (top-of-screen) boolean (row == 0 indicates "tos")
- created an sbbs_t::ungetstr() method
- keep track if in pause (hit a key) prompt, for special mouse behavior

new JS console object:
- row property
- tos property is now read-only (and deprecated)
- new methods:
  add_hotspot()
  clear_hotspots()
  scroll_hotspots()

redrwstr() gets some UTF8 touch-ups as part of this commit. <shrug>

Don't suppress the display of the "from network address" just because there's
an '@' in the "from name" - some Internet email (e.g. SPAM) "From" names
include '@'s to try and follow the reader. <sigh>

wrapper for utf8_normalize_str() and utf8_replace_chars with the proper
arguments.
This will fix *a* problem with UTF-8 message not being converted to CP437 in
QWK packets correctly (we were just normalizing, not fully converting).
Also got rid of the defunct DLLCALL usage str_util.c

characters in message headers and body text will be converted to CP437.
Also include a new field in HEADERS.DAT: utf8 = true/false to indicate that
the message headers and body text contain UTF-8 encoding (not CP437).

would reuse the same buffer where the message subject (list of filenames)
was stored causing havok. Reported by Alterego (ALTERANT).

can't use it as an argument to sprintf(str, ...)
Also, use getfname()... more.

- bstrlen() moved to sbbs_t, accepts an option pmode argument so it can account
  for UTF-8 encoded strings correctly
- JS console.strlen() now accepts an optional pmode argument (e.g. P_UTF8)
- Renamed sbbs_t::utf8_to_cp437 to sbbs_t::print_utf8_as_cp437
- Create/use msghdr_hfield() to perform UTF-8->CP437 conversions as needed for
  printing/copying UTF-8 encoded message header fields.
- Defined XTRN_UTF8 misc setting flag. If a message editor does *not* have this
  flag, it is assumed to *not* support UTF-8. Will likely use this for UTF-8
  doors as some point too (none known to exist, yet).

show_msghdr()

flag in the message header.
When displaying message header fields containing UTF-8 using show_msghdr()
with text.dat string or with msghdr.asc and @-codes, do the "dance" to be sure
it's displayed correctly depending on the user's terminal (UTF-8 or not).

to putmg() when displaying messages in the sub on the terminal server.
E.g. to disable word-wrap for *all* messages displayed in a sub, set P_WORDWRAP
in sub_t.n_pmode.

support in putmsg/printfile, etc. on per-use basis.
Add per-sub-board P-mode flags (so "Extra Attribute Codes" can be disabled
on a per-sub-board basis).

with ZWNBSP/BOM UTF-8 sequence) and messages (with the "CHRS: UTF-8"
FTN control paragra or MIME "charset=utf-8" parts).
Not all UNICODE codepoints are supported (obviously).
Tested with various files from ftp://columbia.edu/kermit/charsets/
(e.g. test.utf8, utf8-boxes.txt)

to a text/html part of a multi-part MIME encoded message if no text/plain part
exists.
Changed smbmsg_t.charset to smbmsg_t.text_charset.
Added smbmsg_t.text_subtype (e.g. "plain" or "html").
Fixed issue with parsing parsed plain-text when the charset was the last
element of the MIME-part header.
MIMEDecodedPlainTextFmt text.dat line now includes the text sub-type arg

as well as the auxattr "Attach" when either FILEATTACH or MIMEATTACH is set
(requires an updated MsgAttr line in text.dat).

Expanded codes will not *not* go beyond the terminal column width (minus 1).
If you need the old/wrap behavior, add a "-W" modifier to your @-code.
If a length value is specified with -W, it is ignored.

- MSG_TO, MSG_FROM, MSG_SUBJECT now reflect the header values passed
  to sbbs_t::show_msghdr(), JS bbs.show_msg_header() and not necessarily the
  actual stored (e.g. MIME-encoded) header values.

New codes:
- MSG_CC - reflect a message's CC list, if it has one
- DATETIMEZONE - combines DATETIME and TIMEZONE in one string

used to display a CC list, when applicable.

show_msghdr(), over-riding the values from the passed smbmsg_t. This is useful
for, say, displaying MIME-decoded values rather than the MIME-encoded versions
of the header fields that you often find in email today.

Renamed MIMEDecodedPlainText to MIMEDecodedPlainTextFmt
(since it is now a printf-style format string).
No special handling of non US-ASCII (e.g. UTF-8) characters... yet.

console.msghdr_top_of_screen):
a hack to let scripts know whether the most-recently displayed message header
was displayed on the top of the terminal screen (or not). This allows us to
show avatars at the top of the screen when the header is up there, rather than
relevative to the bottom of the header (the pos can vary, depending on stuff).

download_file_attachments() and expose via new JS "bbs" method. Currently
this only reall works for the mail base.

- bbs.show_msg()
- bbs.show_msg_header()
Re-worked the JS bbs.netmail() implementation
sbbs::show_msg(), show_msghdr(), msgtotxt() now take an smb_t* argument
(don't use the pseudo-global 'smb' in these functions any longer)
sbbs_t::putmsg() and JS console.putmsg() now accept an optional orig_columns
argument to specify the original column width of a text for intelligent
re-word-wrapping (e.g. as taken from a message header field). Previously, the
original-column value was hard-coded to 80 columns (technically, 79).
sbbs_t::show_msghdr() no longer sends a CRLF if the cursor is already at the
top-of-screen (TOS).
sbbs_t::show_msg() now uses the stored "columns" msg header fields to pass to
putmsg() to intelligently re-word-wrap message bodies for display.
sbbs_t::show_msg() and msgtotxt() return bool now instead of void.
JS MsgBase.get_all_msg_headers() now supports an optional "expand_fields"
argument (defaults to true). I contemplated just getting rid of the (few)
expanding header fields (more like default-value-header fields, like 'id'), but
decided against it, at least for now.
JS MsgBase.put_msg_header(), the "number_or_offset" argument is optional and
not needed if a header object argument is provided. Make this clear in this JS
docs for this method

Note:
I sat on this commit for a while because I noticed occasional errors like this:
    Node 1 <Digital Man> !ERROR 2 (No such file or directory) (WinError 0) in
    readmsgs.cpp line 217 (sbbs_t::loadposts) locking
    "path/to/sub" access=-100 info=smb_locksmbhdr msgbase not open
started cropping up after introducing these changes and which I never
root-caused. But after a clean-build and waiting a week, I haven't seen it
again, so hopefully it was just a incomplete rebuild issue and not a new bug.