Systemd/src/basic/alloc-util.c

82 lines
1.9 KiB
C

/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
/***
This file is part of systemd.
Copyright 2010 Lennart Poettering
systemd is free software; you can redistribute it and/or modify it
under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.
systemd 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/
#include "alloc-util.h"
#include "util.h"
void* memdup(const void *p, size_t l) {
void *r;
assert(p);
r = malloc(l);
if (!r)
return NULL;
memcpy(r, p, l);
return r;
}
void* greedy_realloc(void **p, size_t *allocated, size_t need, size_t size) {
size_t a, newalloc;
void *q;
assert(p);
assert(allocated);
if (*allocated >= need)
return *p;
newalloc = MAX(need * 2, 64u / size);
a = newalloc * size;
/* check for overflows */
if (a < size * need)
return NULL;
q = realloc(*p, a);
if (!q)
return NULL;
*p = q;
*allocated = newalloc;
return q;
}
void* greedy_realloc0(void **p, size_t *allocated, size_t need, size_t size) {
size_t prev;
uint8_t *q;
assert(p);
assert(allocated);
prev = *allocated;
q = greedy_realloc(p, allocated, need, size);
if (!q)
return NULL;
if (*allocated > prev)
memzero(q + prev * size, (*allocated - prev) * size);
return q;
}