git-commit-vandalism/ewah/ewah_rlw.c
Todd Zullinger 484257925f Replace Free Software Foundation address in license notices
The mailing address for the FSF has changed over the years.  Rather than
updating the address across all files, refer readers to gnu.org, as the
GNU GPL documentation now suggests for license notices.  The mailing
address is retained in the full license files (COPYING and LGPL-2.1).

The old address is still present in t/diff-lib/COPYING.  This is
intentional, as the file is used in tests and the contents are not
expected to change.

Signed-off-by: Todd Zullinger <tmz@pobox.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-11-09 13:21:21 +09:00

115 lines
2.9 KiB
C

/**
* Copyright 2013, GitHub, Inc
* Copyright 2009-2013, Daniel Lemire, Cliff Moon,
* David McIntosh, Robert Becho, Google Inc. and Veronika Zenz
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, see <http://www.gnu.org/licenses/>.
*/
#include "git-compat-util.h"
#include "ewok.h"
#include "ewok_rlw.h"
static inline int next_word(struct rlw_iterator *it)
{
if (it->pointer >= it->size)
return 0;
it->rlw.word = &it->buffer[it->pointer];
it->pointer += rlw_get_literal_words(it->rlw.word) + 1;
it->rlw.literal_words = rlw_get_literal_words(it->rlw.word);
it->rlw.running_len = rlw_get_running_len(it->rlw.word);
it->rlw.running_bit = rlw_get_run_bit(it->rlw.word);
it->rlw.literal_word_offset = 0;
return 1;
}
void rlwit_init(struct rlw_iterator *it, struct ewah_bitmap *from_ewah)
{
it->buffer = from_ewah->buffer;
it->size = from_ewah->buffer_size;
it->pointer = 0;
next_word(it);
it->literal_word_start = rlwit_literal_words(it) +
it->rlw.literal_word_offset;
}
void rlwit_discard_first_words(struct rlw_iterator *it, size_t x)
{
while (x > 0) {
size_t discard;
if (it->rlw.running_len > x) {
it->rlw.running_len -= x;
return;
}
x -= it->rlw.running_len;
it->rlw.running_len = 0;
discard = (x > it->rlw.literal_words) ? it->rlw.literal_words : x;
it->literal_word_start += discard;
it->rlw.literal_words -= discard;
x -= discard;
if (x > 0 || rlwit_word_size(it) == 0) {
if (!next_word(it))
break;
it->literal_word_start =
rlwit_literal_words(it) + it->rlw.literal_word_offset;
}
}
}
size_t rlwit_discharge(
struct rlw_iterator *it, struct ewah_bitmap *out, size_t max, int negate)
{
size_t index = 0;
while (index < max && rlwit_word_size(it) > 0) {
size_t pd, pl = it->rlw.running_len;
if (index + pl > max)
pl = max - index;
ewah_add_empty_words(out, it->rlw.running_bit ^ negate, pl);
index += pl;
pd = it->rlw.literal_words;
if (pd + index > max)
pd = max - index;
ewah_add_dirty_words(out,
it->buffer + it->literal_word_start, pd, negate);
rlwit_discard_first_words(it, pd + pl);
index += pd;
}
return index;
}
void rlwit_discharge_empty(struct rlw_iterator *it, struct ewah_bitmap *out)
{
while (rlwit_word_size(it) > 0) {
ewah_add_empty_words(out, 0, rlwit_word_size(it));
rlwit_discard_first_words(it, rlwit_word_size(it));
}
}