cosmopolitan/tool/decode/lib/bitabuilder.c

76 lines
2.9 KiB
C

/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi│
╞══════════════════════════════════════════════════════════════════════════════╡
│ Copyright 2020 Justine Alexandra Roberts Tunney │
│ │
│ 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. │
│ │
│ 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. │
╚─────────────────────────────────────────────────────────────────────────────*/
#include "libc/assert.h"
#include "libc/bits/bits.h"
#include "libc/log/check.h"
#include "libc/macros.h"
#include "libc/mem/mem.h"
#include "libc/runtime/runtime.h"
#include "libc/stdio/stdio.h"
#include "libc/str/str.h"
#include "tool/decode/lib/bitabuilder.h"
/**
* @fileoverview Sparse bit array builder.
*/
struct BitaBuilder {
size_t i, n;
unsigned *p;
};
struct BitaBuilder *bitabuilder_new(void) {
return calloc(1, sizeof(struct BitaBuilder));
}
void bitabuilder_free(struct BitaBuilder **bbpp) {
if (*bbpp) {
free_s(&(*bbpp)->p);
free_s(bbpp);
}
}
/**
* Sets bit.
*
* @return false if out of memory
*/
bool bitabuilder_setbit(struct BitaBuilder *bb, size_t bit) {
void *p2;
size_t i, n;
i = MAX(bb->i, ROUNDUP(bit / CHAR_BIT + 1, __BIGGEST_ALIGNMENT__));
if (i > bb->n) {
n = i + (i >> 2);
if ((p2 = realloc(bb->p, n))) {
memset((char *)p2 + bb->n, 0, n - bb->n);
bb->n = n;
bb->p = p2;
} else {
return false;
}
}
bb->i = i;
bts(bb->p, bit);
return true;
}
bool bitabuilder_fwrite(const struct BitaBuilder *bb, FILE *f) {
return fwrite(bb->p, bb->i, 1, f);
}