zm_mem_utils.h

//
// ZoneMinder Memory Utilities, $Date$, $Revision$
// Copyright (C) 2001-2008 Philip Coombes
// 
// This program 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.
// 
// This program 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 this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
// 

#ifndef ZM_MEM_UTILS_H
#define ZM_MEM_UTILS_H

#include <stdlib.h>
#include "zm.h"

inline void* zm_mallocaligned(unsigned int reqalignment, size_t reqsize) {
	uint8_t* retptr;
#if HAVE_POSIX_MEMALIGN
	if(posix_memalign((void**)&retptr,reqalignment,reqsize) != 0)
		return NULL;
	
	return retptr;
#else
	uint8_t* alloc;
	retptr = (uint8_t*)malloc(reqsize+reqalignment+sizeof(void*));
	
	if(retptr == NULL)
		return NULL;
	
	alloc = retptr + sizeof(void*);
	
	if(((long)alloc % reqalignment) != 0)
		alloc = alloc + (reqalignment - ((long)alloc % reqalignment));
	
	/* Store a pointer before to the start of the block, just before returned aligned memory */
	*(void**)(alloc - sizeof(void*)) = retptr;
	
	return alloc;
#endif
}

inline void zm_freealigned(void* ptr) {
#if HAVE_POSIX_MEMALIGN
	free(ptr);
#else
	/* Start of block is stored before the block if it was allocated by zm_mallocaligned */
	free(*(void**)((uint8_t*)ptr - sizeof(void*)));
#endif
}

inline char *mempbrk( register const char *s, const char *accept, size_t limit )
{
    if ( limit <= 0 || !s || !accept || !*accept )
        return( 0 );

    register unsigned int i,j;
    size_t acc_len = strlen( accept );

    for ( i = 0; i < limit; s++, i++ )
    {
        for ( j = 0; j < acc_len; j++ )
        {
            if ( *s == accept[j] )
            {
                return( (char *)s );
            }
        }
    }
    return( 0 );
}

inline char *memstr( register const char *s, const char *n, size_t limit )
{
    if ( limit <= 0 || !s || !n )
        return( 0 );

    if ( !*n )
        return( (char *)s );

    register unsigned int i,j,k;
    size_t n_len = strlen( n );

    for ( i = 0; i < limit; i++, s++ )
    {
        if ( *s != *n )
            continue;
        j = 1;
        k = 1;
        while ( true )
        {
            if ( k >= n_len )
                return( (char *)s );
            if ( s[j++] != n[k++] )
                break;
        }
    }
    return( 0 );
}

inline size_t memspn( register const char *s, const char *accept, size_t limit )
{
    if ( limit <= 0 || !s || !accept || !*accept )
        return( 0 );

    register unsigned int i,j;
    size_t acc_len = strlen( accept );

    for ( i = 0; i < limit; s++, i++ )
    {
        register bool found = false;
        for ( j = 0; j < acc_len; j++ )
        {
            if ( *s == accept[j] )
            {
                found = true;
                break;
            }
        }
        if ( !found )
        {
            return( i );
        }
    }
    return( limit );
}

inline size_t memcspn( register const char *s, const char *reject, size_t limit )
{
    if ( limit <= 0 || !s || !reject )
        return( 0 );

    if ( !*reject )
        return( limit );

    register unsigned int i,j;
    size_t rej_len = strlen( reject );

    for ( i = 0; i < limit; s++, i++ )
    {
        for ( j = 0; j < rej_len; j++ )
        {
            if ( *s == reject[j] )
            {
                return( i );
            }
        }
    }
    return( limit );
}

#endif // ZM_MEM_UTILS_H