seanhalle@33: /*
seanhalle@33:  * Copyright 2010  OpenSourceCodeStewardshipFoundation
seanhalle@33:  *
seanhalle@33:  * Licensed under BSD
seanhalle@33:  */
seanhalle@33: 
seanhalle@33: 
seanhalle@33: 
seanhalle@33: #include <stdio.h>
seanhalle@33: #include <malloc.h>
seanhalle@33: 
seanhalle@33: #include "DynArray.h"
seanhalle@33: 
seanhalle@33: //== declarations
seanhalle@33: #define giveInfoFor( array )   &(((PrivDynArrayInfo*)array)[-1])
seanhalle@33: //==
seanhalle@33: 
seanhalle@33: /*This updates the contents of the array variable, by side-effect.  There can
seanhalle@33:  * only ever be one variable that holds a pointer to the dyn array, and all
seanhalle@33:  * accesses must use that variable.  An add can cause the contents of that
seanhalle@33:  * variable to change!  (Meaning the position of the array has moved)
seanhalle@33:  */
seanhalle@33: void *
seanhalle@33: makePrivDynArray2( void ***addrOfArrayVar, int32 numElemsToAllocate, int32 sizeOfElem )
seanhalle@33:  { PrivDynArrayInfo *info;
seanhalle@33:    int32 bytesInArray  = numElemsToAllocate * sizeOfElem;
seanhalle@33:    
seanhalle@33:    info = PR_int__malloc( sizeof(PrivDynArrayInfo) + bytesInArray );
seanhalle@33:    info->addrOfPtrToArray = addrOfArrayVar;
seanhalle@33:    info->sizeOfArray      = numElemsToAllocate;
seanhalle@33:    info->sizeOfElem       = sizeOfElem;
seanhalle@33:    info->numInArray       = 0;
seanhalle@33:    return &(info[1]); //skip over prolog -- info is prolog
seanhalle@33:  }
seanhalle@33: 
seanhalle@33: 
seanhalle@33: /*A dynamic array is same as any other array, but add a DynArrayInfo next
seanhalle@33:  * to it.  Accesses and updates of array indexes are done normally, it's
seanhalle@33:  * only when add a new element into array that use the extra info.
seanhalle@33:  * An add can cause the pointer to the normal array to change..  so must
seanhalle@33:  * be protected to single VP at a time.
seanhalle@33:  *
seanhalle@33:  *Only need to use this Fn when need a new index, higher than any previous
seanhalle@33:  */
seanhalle@33: int32
seanhalle@33: addToDynArray2( void *value, void **array )
seanhalle@33:  { int32 numInArray, sizeOfArray;
seanhalle@33:    PrivDynArrayInfo *info = giveInfoFor(array); //go backward to prolog
seanhalle@33:    
seanhalle@33:    numInArray  = info->numInArray;
seanhalle@33:    sizeOfArray = info->sizeOfArray;
seanhalle@33: 
seanhalle@33:    if( numInArray >= sizeOfArray )
seanhalle@33:     {
seanhalle@33:       array = increaseSizeOfDynArrayTo2( array, sizeOfArray * 2 );
seanhalle@33:       info  = giveInfoFor( array );
seanhalle@33:     }
seanhalle@33: 
seanhalle@33:    array[ numInArray ] = value;
seanhalle@33:    info->numInArray++;
seanhalle@33: 
seanhalle@33:    return numInArray; //index of last elem is one less than num in array
seanhalle@33:  }
seanhalle@33: 
seanhalle@33: 
seanhalle@33: /*Sets num in array to exactly value give 
seanhalle@33:  *Use this when know how many things going to add in -- then can do this
seanhalle@33:  * once and use as normal array afterwards.  If later add another chunk,
seanhalle@33:  * do this again.  Note, this makes new size be just big enough to hold
seanhalle@33:  * highest index, so will do a linear number of copies if use only this.
seanhalle@33:  *To cut down on number of copies, can use the increaseSizeTo Fn to
seanhalle@33:  * exponentially increase size..
seanhalle@33:  */
seanhalle@33: void
seanhalle@33: makeNumInArrayBe2( void **array, int32 numInArray )
seanhalle@33:  { PrivDynArrayInfo *info = giveInfoFor( array );
seanhalle@33:    
seanhalle@33:    if( info->sizeOfArray <= numInArray )
seanhalle@33:     {
seanhalle@33:       array = increaseSizeOfDynArrayTo2( array, numInArray );
seanhalle@33:       info = giveInfoFor( array );
seanhalle@33:     }
seanhalle@33:    info->numInArray = numInArray; //num is highest index plus 1
seanhalle@33:  }
seanhalle@33: 
seanhalle@33: /*Allows highest index to remain higher than index give*/
seanhalle@33: void
seanhalle@33: makeHighestDynArrayIndexBeAtLeast2( void **array, int32 index)
seanhalle@33:  { PrivDynArrayInfo *info = giveInfoFor( array );
seanhalle@33:  
seanhalle@33:    if( index < info->numInArray ) return; //num added diff than size
seanhalle@33:    else makeNumInArrayBe2( array, index );
seanhalle@33:  }
seanhalle@33: 
seanhalle@33: 
seanhalle@33: /*Only use this if certain new size is bigger than current size
seanhalle@33:  */
seanhalle@33: void **
seanhalle@33: increaseSizeOfDynArrayTo2( void **oldArray, int32 newSize )
seanhalle@33:  { int32 oldsizeOfArray, i, numBytesToCopy;
seanhalle@33:    void **newArray;
seanhalle@33:    PrivDynArrayInfo  *oldInfo = giveInfoFor( oldArray );
seanhalle@33:    PrivDynArrayInfo  *newInfo;
seanhalle@33: 
seanhalle@33:    oldsizeOfArray   = oldInfo->sizeOfArray;
seanhalle@33:    if( newSize <= oldsizeOfArray ) return;
seanhalle@33: 
seanhalle@33:    newInfo = PR_int__malloc( newSize * oldInfo->sizeOfElem + sizeof(PrivDynArrayInfo) );
seanhalle@33:    newArray = &(newInfo[1]);
seanhalle@33:    
seanhalle@33:    numBytesToCopy = oldInfo->numInArray * oldInfo->sizeOfElem + sizeof(PrivDynArrayInfo);
seanhalle@33:    memcpy( newInfo, oldInfo, numBytesToCopy ); //copies info + array contents
seanhalle@33:    
seanhalle@33:    *(newInfo->addrOfPtrToArray) = newArray; //change contents of array var
seanhalle@33:    newInfo->sizeOfArray = newSize;
seanhalle@33: 
seanhalle@33:    PR_int__free( oldInfo );
seanhalle@33:    
seanhalle@33:    return newArray;
seanhalle@33:  }
seanhalle@33: 
seanhalle@33: 
seanhalle@33: /* Frees the array, plus the info
seanhalle@33:  */
seanhalle@33: void
seanhalle@33: freeDynArrayDeep2( void *array, FreeFnPtr freeFnPtr )
seanhalle@33:  { PrivDynArrayInfo  *info = giveInfoFor( array );
seanhalle@33:  
seanhalle@33:    forAllInDynArrayDo2( array, freeFnPtr );
seanhalle@33:    PR_int__free( info );
seanhalle@33:  }
seanhalle@33: 
seanhalle@33: /* Only frees the info
seanhalle@33:  */
seanhalle@33: void
seanhalle@33: freeDynArrayFlat2( void *array )
seanhalle@33:  { PrivDynArrayInfo  *info = giveInfoFor( array );
seanhalle@33:  
seanhalle@33:    PR_int__free( info );
seanhalle@33:  }
seanhalle@33: 
seanhalle@33: 
seanhalle@33: /*The function has a fixed prototype: takes a void * returns void
seanhalle@33:  * So, the function has to internally cast void * to whatever data struc..
seanhalle@33:  */
seanhalle@33: void
seanhalle@33: forAllInDynArrayDo2( void *array, DynArrayFnPtr fnPtr )
seanhalle@33:  { PrivDynArrayInfo  *info = giveInfoFor( array );
seanhalle@33:    int32 idx, sizeOfElem;
seanhalle@33:    void *addrOfElem;
seanhalle@33:    
seanhalle@33:    sizeOfElem = info->sizeOfElem;
seanhalle@33:    for( idx = 0; idx < info->numInArray; idx++ )
seanhalle@33:     { addrOfElem = ((int8 *)array) + idx * sizeOfElem;
seanhalle@33:       (*fnPtr)( addrOfElem );
seanhalle@33:     }
seanhalle@33:  }
seanhalle@33: