Improve CD key prevalidation

[kk1201]

Fix #877

ioq3/code/client/cl_main.c

Lines 4720 to 4747 in 5d810e5

	for (i = 0; i < len; i++) {
	ch = *key++;
	if (ch>='a' && ch<='z') {
	ch -= 32;
	}
	switch( ch ) {
	case '2':
	case '3':
	case '7':
	case 'A':
	case 'B':
	case 'C':
	case 'D':
	case 'G':
	case 'H':
	case 'J':
	case 'L':
	case 'P':
	case 'R':
	case 'S':
	case 'T':
	case 'W':
	sum += ch;
	continue;
	default:
	return qfalse;
	}
	}

This snippet in cl_main.c already includes code to ignore case when validating CD key. The issue was that the UI_CDKeyMenu_PreValidateKey function diverged from this and prematurely failed.

[timangus]

ioq3/code/client/cl_main.c

Lines 4721 to 4724 in 5d810e5

	ch = *key++;
	if (ch>='a' && ch<='z') {
	ch -= 32;
	}

This is a bit mad really; it should just use ch = toupper(*key++);. Functionally the same, more obvious what it's doing. Could you employ that method instead, in the original and in your fix. Thanks.

[kk1201]

Of course. I'll do tolower() in both though, I think it makes sense since the behaviour was 50/50 between those two files, Quake 3 keys were lowercase, and it fits better with the following. I had a look at Com_WriteCDKey:

ioq3/code/qcommon/common.c

Lines 2531 to 2572 in 5d810e5

	static void Com_WriteCDKey( const char *filename, const char *ikey ) {
	fileHandle_t f;
	char fbuffer[MAX_OSPATH];
	char key[17];
	#ifndef _WIN32
	mode_t savedumask;
	#endif
	Com_sprintf(fbuffer, sizeof(fbuffer), "%s/q3key", filename);
	Q_strncpyz( key, ikey, 17 );
	if(!CL_CDKeyValidate(key, NULL) ) {
	return;
	}
	#ifndef _WIN32
	savedumask = umask(0077);
	#endif
	f = FS_BaseDir_FOpenFileWrite_HomeState( fbuffer );
	if ( !f ) {
	Com_Printf ("Couldn't write CD key to %s.\n", fbuffer );
	goto out;
	}
	FS_Write( key, 16, f );
	FS_Printf( f, "\n// generated by " PRODUCT_NAME ", do not modify\r\n" );
	FS_Printf( f, "// Do not give this file to ANYONE.\r\n" );
	FS_Printf( f, "// id Software and Activision will NOT ask you to send this file to them.\r\n");
	FS_FCloseFile( f );
	out:
	#ifndef _WIN32
	umask(savedumask);
	#else
	;
	#endif
	}
	#endif

When the game boots up and when you press "Accept" on the CD key menu, the game reads & writes the key to the filesystem. If the key is upper/mixed-case then Com_WriteCDKey also writes it as upper/mixed-case. If we care, we can make it output only the valid Quake 3 lower-case version. Tell me if you'd like that added.

The Steam version always overwrites the q3key in its game path with the uppercase version and reads it, so it doesn't really affect that.