1 /* $Id: bitarray.h,v 1.11 1998/10/16 03:15:04 bsmith Exp bsmith $ */ 2 3 /* 4 5 BT - Bit array objects: used to compactly store logical arrays of variables. 6 7 BTCreate(m,bt) - creates a bit array with enough room to hold m values 8 BTDestroy(bt) - destroys the bit array 9 BTMemzero(m,bt) - zeros the entire bit array (sets all values to false) 10 BTSet(bt,index) - sets a particular entry as true 11 BTClear(bt,index) - sets a particular entry as false 12 BTLookup(bt,index) - returns the value 13 BTLookupSet(bt,index) - returns the value and then sets it true 14 BTLength(m) - returns number of bytes in array with m bits 15 BTView(m,bt) - prints all the entries in a bit array 16 17 These routines do not currently have manual pages. 18 19 The are all implemented as macros with the trivial data structure for efficiency. 20 21 These are not thread safe since they use a few global variables. 22 23 */ 24 #if !defined(__BITARRAY_H) 25 #define __BITARRAY_H 26 27 #if !defined(BITSPERBYTE) 28 #define BITSPERBYTE 8 29 #endif 30 31 typedef char* BT; 32 33 extern char _BT_mask, _BT_c; 34 extern int _BT_idx; 35 36 #define BTView(m,bt) {\ 37 int __i; \ 38 for (__i=0; __i<m; __i++) { \ 39 printf("%d %d\n",__i,BTLookup(bt,__i)); \ 40 }} 41 42 #define BTLength(m) ((m)/BITSPERBYTE+1)*sizeof(char) 43 44 #define BTCreate(m,array) (array = (char *)PetscMalloc(((m)/BITSPERBYTE+1)*sizeof(char)),\ 45 ( !array ) ? 1 : (BTMemzero(m,array),0) ) 46 47 #define BTMemzero(m,array) PetscMemzero(array,(m)/BITSPERBYTE+1) 48 49 #define BTLookupSet(array, index) (_BT_idx = (index)/BITSPERBYTE, \ 50 _BT_c = array[_BT_idx], \ 51 _BT_mask = (char)1 << ((index)%BITSPERBYTE), \ 52 array[_BT_idx] = _BT_c | _BT_mask, \ 53 _BT_c & _BT_mask ) 54 55 #define BTSet(array, index) (_BT_idx = (index)/BITSPERBYTE, \ 56 _BT_c = array[_BT_idx], \ 57 _BT_mask = (char)1 << ((index)%BITSPERBYTE), \ 58 array[_BT_idx] = _BT_c | _BT_mask,0) 59 60 61 #define BTClear(array, index) (_BT_idx = (index)/BITSPERBYTE, \ 62 _BT_c = array[_BT_idx], \ 63 _BT_mask = (char)1 << ((index)%BITSPERBYTE), \ 64 array[_BT_idx] = _BT_c & (~_BT_mask),0) 65 66 #define BTLookup(array, index) (_BT_idx = (index)/BITSPERBYTE, \ 67 _BT_c = array[_BT_idx], \ 68 _BT_mask = (char)1 << ((index)%BITSPERBYTE), \ 69 (_BT_c & _BT_mask) != 0 ) 70 71 #define BTDestroy(array) PetscFree(array) 72 73 #endif 74 75 76