http://snippets.dzone.com/posts Thu, 24 Jul 2008 19:49:04 GMT DZone Snippets: allocator code http://snippets.dzone.com/posts/show/437 <code> <br />//+ Jonas Raoni Soares Silva <br />//@ http://jsfromhell.com <br /> <br />#ifndef __MEMORYBLOCK__ <br />#define __MEMORYBLOCK__ <br /> <br /> <br />//-- includes ----------------------------------------------- <br />#include <stdio.h> <br />#include <stdlib.h> <br /> <br /> <br /> <br />//-- data types --------------------------------------------- <br />typedef struct _MemoryBlock { <br /> void *data; <br /> size_t capacity, used, dataSize; <br />}* MemoryBlock; <br /> <br /> <br /> <br />//-- functions ---------------------------------------------- <br />MemoryBlock getMemoryBlock( register const size_t dataSize, register const size_t initialSize ){ <br /> <br /> MemoryBlock mb = (MemoryBlock)malloc( sizeof( struct _MemoryBlock ) ); <br /> <br /> if( mb ) { <br /> mb->used = 0; <br /> mb->data = NULL; <br /> mb->dataSize = dataSize; <br /> mb->capacity = initialSize && ( mb->data = (void *)malloc( initialSize * dataSize ) ) ? initialSize : 0; <br /> } <br /> return mb; <br />} <br /> <br />void freeMemoryBlock( register const MemoryBlock mb ){ <br /> free( mb->data ); <br /> free( mb ); <br />} <br /> <br />int resizeMemoryBlock( register const size_t newSize, register const MemoryBlock mb ){ <br /> <br /> void *newData = (void *)realloc( mb->data, newSize * mb->dataSize ); <br /> <br /> if( newData ){ <br /> mb->data = newData; <br /> return mb->capacity = newSize; <br /> } <br /> return 0; <br />} <br /> <br />int growMemoryBlock( register const MemoryBlock mb ){ <br /> <br /> size_t delta = mb->capacity > 64 ? mb->capacity / 4 : mb->capacity > 8 ? 16 : 4; <br /> void *newData = (void *)realloc( mb->data, ( mb->capacity + delta ) * mb->dataSize ); <br /> <br /> if( newData ){ <br /> mb->data = newData; <br /> return mb->capacity += delta; <br /> } <br /> return 0; <br />} <br /> <br />int growExMemoryBlock( register const size_t neededBlocks, register const MemoryBlock mb ){ <br /> while( mb->used+neededBlocks > mb->capacity ) <br /> if( !growMemoryBlock( mb ) ) <br /> return 0; <br /> return 1; <br />} <br /> <br />int incMemoryBlock( register const MemoryBlock mb ){ <br /> return mb->used+1 <= mb->capacity || growMemoryBlock( mb ); <br />} <br /> <br />#endif <br /></code> Sat, 02 Jul 2005 03:53:59 GMT http://snippets.dzone.com/posts/show/437 jonasraoni (Jonas Raoni Soares Silva)