| 1 | /* A simple, memory-efficient bitset implementation. |
| 2 | |
| 3 | Copyright (C) 2009 Free Software Foundation, Inc. |
| 4 | |
| 5 | This file is part of Bison, the GNU Compiler Compiler. |
| 6 | |
| 7 | This program is free software: you can redistribute it and/or modify |
| 8 | it under the terms of the GNU General Public License as published by |
| 9 | the Free Software Foundation, either version 3 of the License, or |
| 10 | (at your option) any later version. |
| 11 | |
| 12 | This program is distributed in the hope that it will be useful, |
| 13 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 15 | GNU General Public License for more details. |
| 16 | |
| 17 | You should have received a copy of the GNU General Public License |
| 18 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
| 19 | |
| 20 | #include <config.h> |
| 21 | #include "system.h" |
| 22 | |
| 23 | #include "Sbitset.h" |
| 24 | |
| 25 | Sbitset |
| 26 | Sbitset__new (Sbitset__Index nbits) |
| 27 | { |
| 28 | /* Some functions, like Sbitset__last_byte_mask, will fail if nbits = 0. */ |
| 29 | aver (nbits); |
| 30 | return xcalloc (1, Sbitset__nbytes (nbits)); |
| 31 | } |
| 32 | |
| 33 | Sbitset |
| 34 | Sbitset__new_on_obstack (Sbitset__Index nbits, struct obstack *obstackp) |
| 35 | { |
| 36 | char *result; |
| 37 | char *ptr; |
| 38 | char *end; |
| 39 | aver (nbits); |
| 40 | result = obstack_alloc (obstackp, Sbitset__nbytes (nbits)); |
| 41 | for (ptr = result, end = result + Sbitset__nbytes (nbits); ptr < end; ++ptr) |
| 42 | *ptr = 0; |
| 43 | return result; |
| 44 | } |
| 45 | |
| 46 | void |
| 47 | Sbitset__delete (Sbitset self) |
| 48 | { |
| 49 | free (self); |
| 50 | } |
| 51 | |
| 52 | bool |
| 53 | Sbitset__isEmpty (Sbitset self, Sbitset__Index nbits) |
| 54 | { |
| 55 | char *last = self + Sbitset__nbytes (nbits) - 1; |
| 56 | for (; self < last; ++self) |
| 57 | if (*self != 0) |
| 58 | return false; |
| 59 | return ((*last) & Sbitset__last_byte_mask (nbits)) == 0; |
| 60 | } |
| 61 | |
| 62 | void |
| 63 | Sbitset__fprint(Sbitset self, Sbitset__Index nbits, FILE *file) |
| 64 | { |
| 65 | Sbitset__Index i; |
| 66 | Sbitset itr; |
| 67 | bool first = true; |
| 68 | fprintf (file, |
| 69 | "nbits = %" SBITSET__INDEX__CONVERSION_SPEC ", set = {", |
| 70 | nbits); |
| 71 | SBITSET__FOR_EACH (self, nbits, itr, i) |
| 72 | { |
| 73 | if (first) |
| 74 | first = false; |
| 75 | else |
| 76 | fprintf (file, ","); |
| 77 | fprintf (file, " %" SBITSET__INDEX__CONVERSION_SPEC, i); |
| 78 | } |
| 79 | fprintf (file, " }"); |
| 80 | } |