q_shared.cpp

quakeIII源码这个不用我多说吧

/*
===========================================================================
Copyright (C) 1999-2005 Id Software, Inc.

This file is part of Quake III Arena source code.

Quake III Arena source code is free software; you can redistribute it
and/or modify it under the terms of the GNU General Public License as
published by the Free Software Foundation; either version 2 of the License,
or (at your option) any later version.

Quake III Arena source code is distributed in the hope that it will be
useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with Foobar; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
===========================================================================
*/
// q_shared.c -- stateless support routines that are included in each code dll
#include "q_shared.h"

/*
============================================================================

GROWLISTS

============================================================================
*/

// malloc / free all in one place for debugging
extern "C" void *Com_Allocate( int bytes );
extern "C" void Com_Dealloc( void *ptr );

void Com_InitGrowList( growList_t *list, int maxElements ) {
	list->maxElements = maxElements;
	list->currentElements = 0;
	list->elements = (void **)Com_Allocate( list->maxElements * sizeof( void * ) );
}

int Com_AddToGrowList( growList_t *list, void *data ) {
	void	**old;

	if ( list->currentElements != list->maxElements ) {
		list->elements[list->currentElements] = data;
		return list->currentElements++;
	}

	// grow, reallocate and move
	old = list->elements;

	if ( list->maxElements < 0 ) {
		Com_Error( ERR_FATAL, "Com_AddToGrowList: maxElements = %i", list->maxElements );
	}

	if ( list->maxElements == 0 ) {
		// initialize the list to hold 100 elements
		Com_InitGrowList( list, 100 );
		return Com_AddToGrowList( list, data );
	}

	list->maxElements *= 2;

	Com_DPrintf( "Resizing growlist to %i maxElements\n", list->maxElements );

	list->elements = (void **)Com_Allocate( list->maxElements * sizeof( void * ) );

	if ( !list->elements ) {
		Com_Error( ERR_DROP, "Growlist alloc failed" );
	}

	memcpy( list->elements, old, list->currentElements * sizeof( void * ) );

	Com_Dealloc( old );

	return Com_AddToGrowList( list, data );
}

void *Com_GrowListElement( const growList_t *list, int index ) {
	if ( index < 0 || index >= list->currentElements ) {
		Com_Error( ERR_DROP, "Com_GrowListElement: %i out of range of %i", 
			index, list->currentElements );
	}
	return list->elements[index];
}

int Com_IndexForGrowListElement( const growList_t *list, const void *element ) {
	int		i;

	for ( i = 0 ; i < list->currentElements ; i++ ) {
		if ( list->elements[i] == element ) {
			return i;
		}
	}
	return -1;
}

//============================================================================


float Com_Clamp( float min, float max, float value ) {
	if ( value < min ) {
		return min;
	}
	if ( value > max ) {
		return max;
	}
	return value;
}

/*
============
Com_StringContains
============
*/
const char *Com_StringContains( const char *str1, const char *str2, int casesensitive) {
	int len, i, j;

	len = strlen(str1) - strlen(str2);
	for (i = 0; i <= len; i++, str1++) {
		for (j = 0; str2[j]; j++) {
			if (casesensitive) {
				if (str1[j] != str2[j]) {
					break;
				}
			}
			else {
				if (toupper(str1[j]) != toupper(str2[j])) {
					break;
				}
			}
		}
		if (!str2[j]) {
			return str1;
		}
	}
	return NULL;
}

/*
============
Com_Filter
============
*/
int Com_Filter( const char *filter, const char *name, int casesensitive)
{
	char buf[MAX_TOKEN_CHARS];
	const char *ptr;
	int i, found;

	while(*filter) {
		if (*filter == '*') {
			filter++;
			for (i = 0; *filter; i++) {
				if (*filter == '*' || *filter == '?') break;
				buf[i] = *filter;
				filter++;
			}
			buf[i] = '\0';
			if (strlen(buf)) {
				ptr = Com_StringContains(name, buf, casesensitive);
				if (!ptr) return qfalse;
				name = ptr + strlen(buf);
			}
		}
		else if (*filter == '?') {
			filter++;
			name++;
		}
		else if (*filter == '[' && *(filter+1) == '[') {
			filter++;
		}
		else if (*filter == '[') {
			filter++;
			found = qfalse;
			while(*filter && !found) {
				if (*filter == ']' && *(filter+1) != ']') break;
				if (*(filter+1) == '-' && *(filter+2) && (*(filter+2) != ']' || *(filter+3) == ']')) {
					if (casesensitive) {
						if (*name >= *filter && *name <= *(filter+2)) found = qtrue;
					}
					else {
						if (toupper(*name) >= toupper(*filter) &&
							toupper(*name) <= toupper(*(filter+2))) found = qtrue;
					}
					filter += 3;
				}
				else {
					if (casesensitive) {
						if (*filter == *name) found = qtrue;
					}
					else {
						if (toupper(*filter) == toupper(*name)) found = qtrue;
					}
					filter++;
				}
			}
			if (!found) return qfalse;
			while(*filter) {
				if (*filter == ']' && *(filter+1) != ']') break;
				filter++;
			}
			filter++;
			name++;
		}
		else {
			if (casesensitive) {
				if (*filter != *name) return qfalse;
			}
			else {
				if (toupper(*filter) != toupper(*name)) return qfalse;
			}
			filter++;
			name++;
		}
	}
	return qtrue;
}


/*
================
Com_HashString

================
*/
int Com_HashString( const char *fname ) {
	int		i;
	long	hash;
	char	letter;

	hash = 0;
	i = 0;
	while (fname[i] != '\0') {
		letter = tolower(fname[i]);
		if (letter =='.') break;				// don't include extension
		if (letter =='\\') letter = '/';		// damn path names
		hash+=(long)(letter)*(i+119);
		i++;
	}
	hash &= (FILE_HASH_SIZE-1);
	return hash;
}


/*
============
Com_SkipPath
============
*/
char *Com_SkipPath (char *pathname)
{
	char	*last;
	
	last = pathname;
	while (*pathname)
	{
		if (*pathname=='/')
			last = pathname+1;
		pathname++;
	}
	return last;
}

/*
============
Com_StripExtension
============
*/
void Com_StripExtension( const char *in, char *out ) {
	while ( *in && *in != '.' ) {
		*out++ = *in++;
	}
	*out = 0;
}


/*
==================
Com_DefaultExtension
==================
*/
void Com_DefaultExtension (char *path, int maxSize, const char *extension ) {
	char	oldPath[MAX_QPATH];
	char    *src;

//
// if path doesn't have a .EXT, append extension
// (extension should include the .)
//
	src = path + strlen(path) - 1;

	while (*src != '/' && src != path) {
		if ( *src == '.' ) {
			return;                 // it has an extension
		}
		src--;
	}

	Q_strncpyz( oldPath, path, sizeof( oldPath ) );
	Com_sprintf( path, maxSize, "%s%s", oldPath, extension );
}

/*
============================================================================

					BYTE ORDER FUNCTIONS

============================================================================
*/

// can't just use function pointers, or dll linkage can
// mess up when qcommon is included in multiple places
static short	(*_BigShort) (short l);
static short	(*_LittleShort) (short l);
static int		(*_BigLong) (int l);
static int		(*_LittleLong) (int l);
static float	(*_BigFloat) (float l);
static float	(*_LittleFloat) (float l);

short	BigShort(short l){return _BigShort(l);}
short	LittleShort(short l) {return _LittleShort(l);}
int		BigLong (int l) {return _BigLong(l);}
int		LittleLong (int l) {return _LittleLong(l);}
float	BigFloat (float l) {return _BigFloat(l);}
float	LittleFloat (float l) {return _LittleFloat(l);}

short   ShortSwap (short l)
{
	byte    b1,b2;

	b1 = l&255;
	b2 = (l>>8)&255;

	return (b1<<8) + b2;
}

short	ShortNoSwap (short l)
{
	return l;
}

int    LongSwap (int l)
{
	byte    b1,b2,b3,b4;

	b1 = l&255;
	b2 = (l>>8)&255;
	b3 = (l>>16)&255;
	b4 = (l>>24)&255;

	return ((int)b1<<24) + ((int)b2<<16) + ((int)b3<<8) + b4;
}

int	LongNoSwap (int l)
{
	return l;
}

float FloatSwap (float f)
{
	union
	{
		float	f;
		byte	b[4];
	} dat1, dat2;
	
	
	dat1.f = f;
	dat2.b[0] = dat1.b[3];
	dat2.b[1] = dat1.b[2];
	dat2.b[2] = dat1.b[1];
	dat2.b[3] = dat1.b[0];
	return dat2.f;
}

float FloatNoSwap (float f)
{
	return f;
}

/*
================
Swap_Init
================
*/
void Swap_Init (void)
{
	byte	swaptest[2] = {1,0};

// set the byte swapping variables in a portable manner	
	if ( *(short *)swaptest == 1)
	{
		_BigShort = ShortSwap;
		_LittleShort = ShortNoSwap;
		_BigLong = LongSwap;
		_LittleLong = LongNoSwap;
		_BigFloat = FloatSwap;
		_LittleFloat = FloatNoSwap;
	}
	else
	{
		_BigShort = ShortNoSwap;
		_LittleShort = ShortSwap;
		_BigLong = LongNoSwap;
		_LittleLong = LongSwap;
		_BigFloat = FloatNoSwap;
		_LittleFloat = FloatSwap;
	}

}

/*
===============
Com_ParseInfos
===============
*/
int Com_ParseInfos( const char *buf, int max, char infos[][MAX_INFO_STRING] ) {
	const char	*token;
	int		count;
	char	key[MAX_TOKEN_CHARS];

	count = 0;

	while ( 1 ) {
		token = Com_Parse( &buf );
		if ( !token[0] ) {
			break;
		}
		if ( strcmp( token, "{" ) ) {
			Com_Printf( "Missing { in info file\n" );
			break;
		}

		if ( count == max ) {
			Com_Printf( "Max infos exceeded\n" );
			break;
		}

		infos[count][0] = 0;
		while ( 1 ) {
			token = Com_Parse( &buf );
			if ( !token[0] ) {
				Com_Printf( "Unexpected end of info file\n" );
				break;
			}
			if ( !strcmp( token, "}" ) ) {
				break;
			}
			Q_strncpyz( key, token, sizeof( key ) );

			token = Com_ParseOnLine( &buf );
			if ( !token[0] ) {
				token = "<NULL>";
			}
			Info_SetValueForKey( infos[count], key, token );
		}
		count++;
	}

	return count;
}



/*
============================================================================

					LIBRARY REPLACEMENT FUNCTIONS

============================================================================
*/

int Q_isprint( int c )
{
	if ( c >= 0x20 && c <= 0x7E )
		return ( 1 );
	return ( 0 );
}

int Q_islower( int c )
{
	if (c >= 'a' && c <= 'z')
		return ( 1 );
	return ( 0 );
}