X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=lib%2Fbitmap.c;h=4b4e13e56051051ba61c5e288a9503a325789212;hb=a5ed8fe32cb3c996837c61af2e358fa34dc9936f;hp=cab7e6d261e833add569b6d20edb355febfa870e;hpb=064af42167bf4fc9aaea2702d80ce08074b889c0;p=sliver-openvswitch.git diff --git a/lib/bitmap.c b/lib/bitmap.c index cab7e6d26..4b4e13e56 100644 --- a/lib/bitmap.c +++ b/lib/bitmap.c @@ -1,22 +1,45 @@ /* - * Copyright (c) 2008 Nicira Networks. + * Copyright (c) 2008, 2009, 2011, 2014 Nicira, Inc. * - * Permission to use, copy, modify, and/or distribute this software for any - * purpose with or without fee is hereby granted, provided that the above - * copyright notice and this permission notice appear in all copies. + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at: * - * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES - * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF - * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR - * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES - * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN - * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF - * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. */ #include #include "bitmap.h" #include +#include "util.h" + +/* Allocates and returns a bitmap initialized to all-1-bits. */ +unsigned long * +bitmap_allocate1(size_t n_bits) +{ + size_t n_bytes = bitmap_n_bytes(n_bits); + size_t n_longs = bitmap_n_longs(n_bits); + size_t r_bits = n_bits % BITMAP_ULONG_BITS; + unsigned long *bitmap; + + /* Allocate and initialize most of the bitmap. */ + bitmap = xmalloc(n_bytes); + memset(bitmap, 0xff, n_bytes); + + /* Ensure that the last "unsigned long" in the bitmap only has as many + * 1-bits as there actually should be. */ + if (r_bits) { + bitmap[n_longs - 1] = (1UL << r_bits) - 1; + } + + return bitmap; +} /* Sets 'count' consecutive bits in 'bitmap', starting at bit offset 'start', * to 'value'. */ @@ -53,3 +76,36 @@ bitmap_equal(const unsigned long *a, const unsigned long *b, size_t n) } return true; } + +/* Scans 'bitmap' from bit offset 'start' to 'end', excluding 'end' itself. + * Returns the bit offset of the lowest-numbered bit set to 'target', or 'end' + * if all of the bits are set to '!target'. */ +size_t +bitmap_scan(const unsigned long int *bitmap, bool target, + size_t start, size_t end) +{ + /* XXX slow */ + size_t i; + + for (i = start; i < end; i++) { + if (bitmap_is_set(bitmap, i) == target) { + break; + } + } + return i; +} + +/* Returns the number of 1-bits in the 'n'-bit bitmap at 'bitmap'. */ +size_t +bitmap_count1(const unsigned long int *bitmap, size_t n) +{ + size_t i; + size_t count = 0; + + BUILD_ASSERT(ULONG_MAX <= UINT64_MAX); + for (i = 0; i < BITMAP_N_LONGS(n); i++) { + count += count_1bits(bitmap[i]); + } + + return count; +}