Fix crash when ending a chat line with ¬

[rherriman]

When outside of a game, you can type "¬" with impunity, unless it is the last character in the line when you press Enter.

The source of the issue seems to lie in std::string CPlayerManagerImpl::GetChatLine(), which examines the line buffer to grab the most recent line of chat by finding the last "¬" character (the assumption being that it marked the end of the line prior to the one we want). A substring is returned containing everything following that point. Unfortunately, when the last character in the buffer just happens to be a "¬", an invalid index is submitted to substr, hence the crash.

Checking for this specific condition is unfortunately not sufficient, because another issue would remain: typing "asdf ¬ qwerty" followed by Enter would result in "qwerty" being returned, rather than the full string.

Here's the backtrace:

* thread #1, queue = 'com.apple.main-thread', stop reason = signal SIGABRT
  * frame #0: 0x00007fff702ab33a libsystem_kernel.dylib`__pthread_kill + 10
    frame #1: 0x00007fff70367e60 libsystem_pthread.dylib`pthread_kill + 430
    frame #2: 0x00007fff70232808 libsystem_c.dylib`abort + 120
    frame #3: 0x00007fff6d492458 libc++abi.dylib`abort_message + 231
    frame #4: 0x00007fff6d4838a7 libc++abi.dylib`demangling_terminate_handler() + 238
    frame #5: 0x00007fff6efbe5b1 libobjc.A.dylib`_objc_terminate() + 104
    frame #6: 0x00007fff6d491887 libc++abi.dylib`std::__terminate(void (*)()) + 8
    frame #7: 0x00007fff6d4941a2 libc++abi.dylib`__cxxabiv1::failed_throw(__cxxabiv1::__cxa_exception*) + 27
    frame #8: 0x00007fff6d494169 libc++abi.dylib`__cxa_throw + 113
    frame #9: 0x00007fff6d4750c8 libc++.1.dylib`std::__1::__throw_out_of_range(char const*) + 56
    frame #10: 0x00007fff6d466b0e libc++.1.dylib`std::__1::__basic_string_common<true>::__throw_out_of_range() const + 16
    frame #11: 0x00007fff6d466daf libc++.1.dylib`std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> >::basic_string(std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&, unsigned long, unsigned long, std::__1::allocator<char> const&) + 195
    frame #12: 0x00000001000f34f7 Avara`std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> >::substr(this="¬", __pos=3, __n=18446744073709551615) const at string:3280:12
    frame #13: 0x00000001000f33b5 Avara`CPlayerManagerImpl::GetChatLine(this=0x0000000102905000) at CPlayerManager.cpp:745:20
    frame #14: 0x00000001000f2d47 Avara`CPlayerManagerImpl::RosterMessageText(this=0x0000000102905000, len=0, c="    \"normal\": [\n        -0.11374074921797517,\n        -0.9801174944686045,\n        0.1624628061341268\n      ],\n      \"tris\": [\n?-\x89\x01\x01") at CPlayerManager.cpp:710:90
    frame #15: 0x00000001000d862c Avara`CNetManager::ReceiveRosterMessage(this=0x00000001022a5ee0, slotId=0, len=1, c="\r    \"normal\": [\n        -0.11374074921797517,\n        -0.9801174944686045,\n        0.1624628061341268\n      ],\n      \"tris\": [\n?-\x89\x01\x01") at CNetManager.cpp:349:20
    frame #16: 0x0000000100026c34 Avara`CProtoControl::DelayedPacketHandler(this=0x000000010228d1c0, thePacket=0x0000000101892c80) at CProtoControl.cpp:89:21
    frame #17: 0x0000000100026879 Avara`DelayedProtoHandler(thePacket=0x0000000101892c80, userData="\x98K.") at CProtoControl.cpp:37:24
    frame #18: 0x000000010000ee24 Avara`CCommManager::ProcessQueue(this=0x0000000100f9d990) at CCommManager.cpp:363:33
    frame #19: 0x00000001000d7a41 Avara`CNetManager::ProcessQueue(this=0x00000001022a5ee0) at CNetManager.cpp:188:21
    frame #20: 0x00000001000c3360 Avara`CAvaraGame::GameTick(this=0x0000000102911c00) at CAvaraGame.cpp:815:13
    frame #21: 0x000000010005c3d9 Avara`CAvaraAppImpl::idle(this=0x00000001022612a0) at CAvaraApp.cpp:105:17
    frame #22: 0x0000000100220678 Avara`nanogui::mainloop(refresh=16) at common.cpp:82:25
    frame #23: 0x00000001002c02f7 Avara`main(argc=1, argv=0x00007ffeefbff5d8) at Avara.cpp:67:5
    frame #24: 0x00007fff70163cc9 libdyld.dylib`start + 1
    frame #25: 0x00007fff70163cc9 libdyld.dylib`start + 1

[assertivist]

This is fixed but that code still lives on. I think it is needed to divide lines up for the chat tab.

I also don't really like the stuff that goes all the way back out to GUI code to make chat lines, but actually thats how the original did it too:

Avara/src/game/CPlayerManager.cpp

Lines 609 to 680 in 30ded35

	void CPlayerManagerImpl::FlushMessageText(
	Boolean forceAll)
	{
	Str255 fullLine;
	short maxLen;
	short baseLen;
	GrafPtr savedPort;
	TextSettings savedTexs;
	OSErr err;
	GetPort(&savedPort);
	SetPort(theRoster->itsWindow);
	GetSetTextSettings(&savedTexs, geneva, 0, 9, srcOr);
	do
	{
	BlockMoveData(playerName, fullLine, playerName[0] + 1);
	#if 0
	while(fullLine[0] && fullLine[fullLine[0]] == 32)
	{ fullLine[0]--;
	}
	#endif
	TruncString(kChatMessageWidth/3, fullLine, smTruncEnd);
	fullLine[++fullLine[0]] = ':';
	fullLine[++fullLine[0]] = ' ';
	baseLen = fullLine[0];
	maxLen = lineBuffer[0];
	if(maxLen + baseLen > 250)
	{ maxLen = 250 - baseLen;
	}
	BlockMoveData(lineBuffer+1, fullLine + 1 + baseLen, maxLen);
	fullLine[0] += maxLen;
	#if 1
	err = WordWrapString(fullLine);
	#else
	err = TruncString(kChatMessageWidth, fullLine, smTruncEnd);
	#endif
	if(err == 1 || forceAll)
	{ short outLen;
	if(err == 1)
	{ outLen = fullLine[0] - baseLen - 1;
	}
	else
	{ outLen = maxLen;
	}
	if(outLen != 0) theRoster->NewChatLine(fullLine);
	BlockMoveData(lineBuffer + outLen + 1, lineBuffer + 1, lineBuffer[0] - outLen);
	lineBuffer[0] -= outLen;
	if(err == 0) forceAll = false;
	}
	} while(err == 1 || forceAll);
	isLocalPlayer = (theNetManager->itsCommManager->myId == slot);
	if(isLocalPlayer)
	{ theRoster->SetChatLine(fullLine);
	}
	RestoreTextSettings(&savedTexs);
	SetPort(savedPort);
	}

additionally, i was gonna say something about making it match by renaming the function to FlushMessage but then i realized that I ALSO ignored an old function RosterKeyPress when i was making special characters show up in the roster chat! so i have no room to talk! And i'm closing this!